JP6139487B2 - Light-shielded roll-shaped film, method for producing light-shielded roll-shaped film, roll-shaped film containing thermal polymerization initiator, method for producing roll-shaped film containing thermal polymerization initiator, hard coat film, method for producing hard-coated film , Polarizing plate and liquid crystal display device - Google Patents

Description

  The present invention relates to a light-shielded roll film, a hard coat film, a production method thereof, a polarizing plate, and a liquid crystal display device. More specifically, a light-shielded roll-shaped film and a light-shielded roll-shaped film manufacturing method that can increase the surface hardness when a hard coat layer is laminated, a roll-shaped film containing a thermal polymerization initiator, and a thermal polymerization initiator. A method for producing a roll-shaped film comprising the above-described light-shielded roll-shaped film or a hard-coated film using a roll-shaped film comprising a thermal polymerization initiator, a method for producing these hard-coated films, and the aforementioned hard-coated film The present invention relates to the polarizing plate and the liquid crystal display device used.

  Many sheet members used in optical devices such as liquid crystal displays are manufactured from polymer films. Many polymer films are scratched by contact with other objects and friction, so the sheet member is hard on the polymer film so that it will not be scratched during the manufacturing or use of optical equipment. There are many films (hard coat film) provided with a coat.

  It has also been proposed to use a component that is cured by irradiating the polymer film itself with light used for a hard coat layer as a component of the solution-forming solution. For example, Patent Document 1 discloses an ethylenically unsaturated monomer and / or a functional group-containing ethylenically unsaturated monomer and light in a cellulose ester dope composition used for forming a cellulose ester film by a solution casting film forming method. The cellulose ester dope composition containing a polymerization initiator is cast on the endless metal support of the solution casting film forming apparatus until the drying of the web is completed in the drying apparatus. A method of irradiating with ultraviolet rays is described.

JP 2002-020410 A

  However, for the purpose of improving the surface hardness of the polymer film, the inventors investigated the surface hardness of the cellulose ester film described in Patent Document 1 in which a monomer was added to the cellulose ester dope and exposed and cured after film formation. Due to insufficient curing, high surface hardness could not be obtained.

  The problem to be solved by the present invention is to provide a roll film that can increase the surface hardness when a hard coat layer is laminated.

As a result of intensive studies by the present inventors for the above purpose, when forming a hard coat layer on a cellulose ester film, there is little or no polymerization initiator in the vicinity of the interface between the cellulose ester film and the hard coat layer. However, since the polymerization reaction of the polymerizable compound in the composition for forming the hard coat layer is difficult to proceed, it has been estimated that the surface hardness when the hard coat layer is laminated is low.
Therefore, as a result of further studies by the present inventors, a hard coat layer was laminated by winding up a film having at least an air interface with a cellulose ester layer containing a specific amount of a polymerization initiator in a roll shape. It was found that sometimes the surface hardness can be increased, and a light-shielded roll film having good cutting properties after winding after the hard coat layer is provided can be provided.
The present invention, which is a specific means for solving the above problems, is as follows.

[1] A film having one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester and the above-described cellulose ester in a roll shape. A rolled film wound up;
A light-shielded roll-shaped film having a light-shielding material that covers the aforementioned roll-shaped film and has a transmittance of 0.1% or less for UV light in a wavelength band of 200 to 450 nm.
[2] The light-shielded roll film according to [1], wherein the shielding material is a black light-shielding packaging or a light-shielding packaging having a metal thin film layer.
[3] The method according to [1] or [2], comprising two or more layers, further including a base material layer, and containing 1% by mass or more of an ultraviolet absorber with respect to the polymer contained in the base material layer. The light-shielded roll film described.
[4] The light-shielded roll film according to [3], wherein the polymer contained in the substrate layer is a cellulose ester.
[5] A film having one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a thermal polymerization initiator with respect to the cellulose ester and the above cellulose ester at the air interface is in a roll shape. A rolled film containing a thermal polymerization initiator wound up.
[6] The composition according to [5], comprising two or more layers, further comprising a base material layer, and containing 0.5% by mass or more of an ultraviolet absorber with respect to the polymer contained in the base material layer. A roll film containing a thermal polymerization initiator.
[7] A roll film containing the thermal polymerization initiator according to [6], wherein the polymer contained in the substrate layer is a cellulose ester.
[8] A step of forming a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester and the aforementioned cellulose ester at the air interface. (1) and
A step (2) of winding the above film into a roll to form a roll film;
The manufacturing method of the light-shielded roll-shaped film including the process (3) which light-shields the above-mentioned roll-shaped film using the shielding material whose transmittance | permeability of UV light of a 200-450 nm wavelength band is 0.1% or less.
[9] A base layer composition containing a polymer and the above cellulose ester and a composition containing 2 to 20% by mass of a photopolymerization initiator based on the above cellulose ester are successively cast on a support or A step (1-1) of forming a film having at least the above-mentioned cellulose ester layer at the air interface by co-casting;
The method for producing a light-shielded roll film according to [8], comprising a step (1-2) of peeling the film having the cellulose ester layer at least at the air interface from the support.
[10] A step of forming a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a thermal polymerization initiator with respect to the cellulose ester and the cellulose ester at the air interface. (1S),
The manufacturing method of the roll-shaped film containing a thermal-polymerization initiator including the process (2) which winds up the above-mentioned film in roll shape, and forms a roll-shaped film.
[11] A base layer composition containing a polymer and the above cellulose ester and a composition containing 2 to 20% by mass of a thermal polymerization initiator based on the above cellulose ester are successively cast on a support or A step (1S-1) of forming a film having at least the above-mentioned cellulose ester layer at the air interface by co-casting;
The manufacturing method of the roll-shaped film containing the thermal-polymerization initiator as described in [10] including the process (1S-2) which peels the film which has the above-mentioned cellulose-ester layer at an air interface at least from the above-mentioned support body.
[12] A hard containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the light-shielded roll film according to any one of [1] to [4] Applying the coating layer forming composition (4A);
A method for producing a hard coat film, comprising a step (5) of photocuring the composition for forming a hard coat layer.
[13] A step of forming a film having one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester and the cellulose ester at the air interface. (1) and
(4B) applying a hard coat layer-forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer;
Including the step (5) of photocuring the composition for forming a hard coat layer described above,
The process (1) and the process (4B) described above are performed in an environment where UV light having a wavelength band of 200 to 450 nm is shielded from the start of the process (1) until the process (4B) is completed. A method for producing a hard coat film.
[14] A polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the roll film containing the thermal polymerization initiator according to any one of [5] to [7]. A step (4S) of applying a hard coat layer forming composition comprising:
A step (5) of photocuring the aforementioned composition for forming a hard coat layer;
The manufacturing method of a hard-coat film including the process (6) of thermosetting the above-mentioned composition for hard-coat layer formation.
[15] A step of forming a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a thermal polymerization initiator with respect to the cellulose ester and the cellulose ester at the air interface. (1S),
(4A) applying a hard coat layer-forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer;
A step (5) of photocuring the aforementioned composition for forming a hard coat layer;
The manufacturing method of a hard-coat film including the process (6) of thermosetting the above-mentioned composition for hard-coat layer formation.
[16] The production of the hard coat film according to any one of [12] to [15], wherein the step (5) of photocuring the composition for forming a hard coat layer is a step of irradiating ultraviolet rays. Method.
[17] The method for producing a hard coat film according to any one of [12] to [16], comprising a step of drying the hard coat layer forming composition after the curing step.
[18] A hard coat film produced by the method for producing a hard coat film according to any one of [12] to [17].
[19] A hard containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the light-shielded roll film according to any one of [1] to [4] After the coating layer forming composition is applied,
A hard coat film formed by photocuring.
[20] In an environment in which UV light in the wavelength band of 200 to 450 nm is shielded, the photopolymerization initiator is composed of one layer or two or more layers and is 2 to 20% by mass with respect to the cellulose ester and the cellulose ester. After the composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator is applied on the aforementioned cellulose ester layer of the film having a cellulose ester layer containing at least at the air interface,
A hard coat film formed by photocuring.
[21] A polymerizable monomer and a photopolymerization initiator are formed on the cellulose ester layer of the film obtained by unwinding the roll film containing the thermal polymerization initiator according to any one of [5] to [7]. After the composition for forming a hard coat layer containing is applied,
A hard coat film formed by photocuring and heat curing.
[22] The aforementioned cellulose of a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 2 to 20% by mass of a thermal polymerization initiator with respect to the cellulose ester and the aforementioned cellulose ester at the air interface After the hard coat layer forming composition containing a polymerizable monomer and a photopolymerization initiator is applied on the ester layer,
A hard coat film formed by photocuring and heat curing.
[23] A polarizing plate having a polarizer and the hard coat film according to any one of [18] to [22].
[24] A liquid crystal display device having a liquid crystal cell and the hard coat film according to any one of [18] to [22] or the polarizing plate according to [14].

  According to the present invention, it is possible to provide a roll film that can increase the surface hardness when the hard coat layer is laminated.

It is the schematic of a casting apparatus. It is an enlarged view of a casting die. It is the schematic of a film manufacturing equipment.

  Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

[Shaded rolled film]
The light-shielded roll film of the present invention is composed of one layer or two or more layers, and has at least an air interface with a cellulose ester layer containing 2 to 20% by mass of a photopolymerization initiator based on cellulose ester and cellulose ester. A roll-shaped film in which a film having a roll is wound;
And a light shielding material that covers the roll film and has a transmittance of 0.01% or less of UV light in a wavelength band of 200 to 450 nm.
With such a configuration, the light-shielded roll film of the present invention can have a high surface hardness when the hard coat layer is laminated, and has good cutting properties after being wound after the hard coat layer is provided.

[Rolled film containing thermal polymerization initiator]
The light-shielded roll film containing the thermal polymerization initiator of the present invention is composed of one layer or two or more layers, and the cellulose ester contains 2 to 20% by mass of the thermal polymerization initiator based on the cellulose ester and the cellulose ester. A roll film in which a film having a layer at least at an air interface is wound into a roll.
With such a configuration, the roll film containing the thermal polymerization initiator of the present invention can increase the surface hardness when the hard coat layer is laminated, and has a cutting property after being wound after the hard coat layer is provided. good.

  Hereinafter, the light-shielded roll film of the present invention and the roll film containing the thermal polymerization initiator of the present invention are collectively referred to as the roll film of the present invention.

The shielding material preferably has a UV light transmittance of 0.1% or less in a wavelength band of 200 to 450 nm, a UV light transmittance of 0.03% or less, and a UV light transmittance of 0.1% or less. More preferably, the content is not more than 01%.
In the light-shielded roll film of the present invention, the shielding material is preferably a black light-shielding packaging or a light-shielding packaging having a metal thin film layer.
As the black light-shielding packaging, a film containing a black colorant (carbon black, titanium black, etc.) is preferable, and a black film kneaded with carbon black is more preferable. A commercially available product may be used as the black light-shielding packaging, and examples thereof include black polyolefin film (shako-BPF) (Takeda Sangyo Co., Ltd.).
The light-shielding packaging having a metal thin film layer is preferably a film including a metal vapor-deposited layer (aluminum vapor-deposited layer, chromium-deposited layer, etc.), and more preferably an aluminum-deposited film. Commercially available light-shielding packaging having a metal thin film layer may be used. For example, VM-PET, VM-TAC (both Toray Film Processing Co., Ltd.), ML (metal vapor deposition film) (Mitsui Chemicals Tosero Co., Ltd.) )).

The light-shielded roll film of the present invention is preferably composed of two or more layers and further includes a base material layer.
The light-shielded roll film of the present invention comprises two or more layers, further includes a base material layer, and more preferably includes 0.5 or more ultraviolet absorbers with respect to the polymer contained in the base material layer, It is particularly preferable to include 1.0% by mass or more of the ultraviolet absorber, and it is particularly preferable to include 2.0% by mass or more of the ultraviolet absorber.

  In the light-shielded roll film of the present invention, the polymer contained in the base material layer is preferably a cellulose ester or an acrylic resin, and more preferably a cellulose ester. About the preferable aspect of an acrylic resin, it is the same as that of the acrylic resin preferably used for the below-mentioned hard-coat layer.

  A preferred embodiment of the roll film of the present invention will be described in the following method for producing a roll film of the present invention.

[Method for producing roll film]
The method for producing a roll film of the present invention comprises at least an air interface comprising a cellulose ester layer comprising one layer or two or more layers and containing 2 to 20% by mass of a photopolymerization initiator based on the cellulose ester and the cellulose ester. Forming a film having (1),
And (2) forming at least a roll-shaped film by winding the film into a roll shape.
When manufacturing the light-shielded roll-shaped film, the process (3) which light-shields a roll-shaped film further using the shielding material whose transmittance | permeability of the UV light of a 200-450 nm wavelength band is 0.1% or less is further carried out. Including.

  The manufacturing method of the roll-shaped film of this invention is a composition for a base material layer containing a polymer, and a composition containing 2-20 mass% photoinitiator with respect to a cellulose ester and a cellulose ester on a support body. A step (1-1) of forming a film having a cellulose ester layer at least at the air interface by successive casting or co-casting, and a step of peeling the film having at least the cellulose ester layer at the air interface from the support ( It is preferable to include 1-2).

  In FIG. 1, an example of the casting apparatus 10 which can be used for the manufacturing method of the roll-shaped film of this invention is shown. The casting apparatus 10 includes a support 12 and a casting die 14. The support 12 may be a rotating drum or a band, but for example, a rotating drum as shown in FIG. 1 is preferable. The casting die 14 joins the flow of the first solution 16 (first solution flow) and the flow of the second solution 18 (second solution flow), and then discharge port 20 (FIG. 2) formed at the tip. The casting film 22 is formed by allowing it to flow out on the support 12 traveling from the reference). That is, the casting apparatus 10 forms the laminated body (casting film) 22 by a known co-casting method.

The first solution 16 forms a cast film 22a derived from the polymerizable compound-containing composition of the cast film 22, and is, for example, a composition containing a polymerizable compound and a polymer such as cellulose acylate. The polymer solution preferably has a viscosity of 100 Pa · s or less. On the other hand, the 2nd solution 18 forms the casting film 22b derived from the initiator containing composition of the laminated body (casting film) 22, The composition in which polymerizable compounds, such as a monomer and an oligomer, were melt | dissolved in the solvent. Preferably, it is a solution having a viscosity of 10 Pa · s or less. The viscosity ratio of the first and second solutions 16 and 18 is preferably 10: 1 or more (where X / Y ≧ 10, where X is the viscosity of the first solution and Y is the viscosity of the second solution). Preferably satisfy). Examples of polymerizable compounds such as monomers and oligomers include a curing agent that is cured by ultraviolet rays and a curable polymerization agent.
However, the above embodiment is an example of the present invention, and any of the casting film 22a derived from the polymerizable compound-containing composition and the casting film 22b derived from the initiator-containing composition may be on the support side, that is, Any of them may be the first solution 16 or the second solution 18.

  As shown in FIG. 2, the casting die 14 is formed with a first supply port 24, a second supply port 26, a first flow path 28, and a second flow path 30 in addition to the discharge port 20 described above. . The first solution 16 is supplied from the first supply port 24, and the second solution 18 is supplied from the second supply port 26. The first and second flow paths 28 and 30 are slit-shaped flow paths whose cross-sectional shape perpendicular to the direction in which the solution flows is long in the width direction of the casting film 22 (the depth direction in FIGS. 1 and 2). The first flow path 28 is formed so as to connect the first supply port 24 and the discharge port 20, and the second flow path 30 is formed so as to connect the second supply port 26 and the discharge port 20. Yes.

  Thus, in the casting die 14, the most downstream ends of the first and second flow paths 28 and 30 are connected to the discharge port 20, and the first and second solutions 16 and 18 are connected to the discharge port. After being merged in an area (merging portion) near 20, it is discharged from the discharge port 20 to the support 12.

  Moreover, in the said embodiment, although the example which applies this invention to the casting apparatus which co-casts the 1st, 2nd solution was demonstrated, in addition to the 1st, 2nd solution, the 3rd solution is co-cast. The present invention may be applied to a casting apparatus.

  Further, the casting apparatus may be provided with a temperature control mechanism for adjusting the peripheral surface temperature of the support by heating or cooling the support. Further, a decompression chamber may be provided in the vicinity of the casting die on the upstream side in the rotational direction of the support, and the upstream side in the rotational direction of the support may be decompressed relative to the casting die. Furthermore, you may provide the air blower which blows in the circumferential direction of a support body, the duct for flowing the wind from an air blower along the outer periphery of a support body, etc. In addition, when blowing along the outer periphery of a support body, it is preferable to blow in the direction opposite to the moving direction of a support body.

  Hereinafter, based on FIG. 3, the film manufacturing equipment 60 which manufactures the film before making it into the roll shape of a roll-shaped film using the said casting apparatus 10 (refer FIG. 1) is demonstrated. In the film manufacturing facility 60, a drying unit 62 is provided on the downstream side of the casting apparatus 10. The laminate (casting film) 22 formed on the support 12 by the casting apparatus 10 is turned into a wet film 64 by cooling the support 12, for example. Then, the wet film 64 is peeled off from the support 12, conveyed by the roller 68, and sent to the drying unit 62.

  The drying unit 62 is provided with a tenter 70. The tenter 70 is provided with a plurality of clips 72 as holding means for holding the side ends of the wet film 64 on both sides of the transport path of the wet film 64. When the wet film 64 cannot withstand gripping by the clip 72, for example, when the content of the solvent is too high and tears by gripping, the side end of the wet film 64 is replaced with a pin instead of the clip 72. A pin may be pierced into the portion, thereby holding the wet film 64.

  The plurality of clips 72 are provided in an endless chain (not shown) that continuously travels, and the travel path of the clips 72 can be changed by displacing the travel path of the chain. The width of the wet film 64 may be regulated by appropriately adjusting the distance between the clip 72 and the clip 72 disposed on both sides of the wet film 64.

  The tenter 70 is provided with a blower duct 74 that blows the temperature-adjusted dry air onto the wet film 64, and by this blow, the wet film 64 is dried while being held and conveyed by the clip 72.

  Note that the tenter 70 does not have to be arranged when the roller can be supported by the peripheral surface of the roller and conveyed by the rotation of the roller.

  The wet film 64 released from the clip 72 is guided to a cutting device 76 provided downstream of the tenter 70. A grip mark remains at the grip position gripped by the clip 72 of the wet film 64. The cutting device 76 continuously cuts the side end portion of the wet film 64 so that the grip mark is separated from the central portion that is the product of the polymer film 50.

  Downstream of the cutting device 76, there is a drying chamber 80 that includes a plurality of rollers 78 that support the wet film 64 with both ends cut off on the peripheral surface, and is supplied with dry air. The roller 78 includes a driving roller that conveys the wet film 64 by being rotationally driven in the circumferential direction. The supplied dry air is adjusted to a predetermined temperature and humidity. With this dry air, the wet film 64 is further dried and completely dried. The degree of “complete” is a degree of drying that does not cause a problem as a product, and the residual solvent amount does not necessarily have to be 0 (zero). The completely dried film is referred to as a dry film 82 in the following description.

  The dried film 82 that has passed through the drying unit 62 is sent to the curing device 84. The curing device 84 has a light source that emits ultraviolet rays, and irradiates the guided dry film 82 with ultraviolet rays from the light source. By this irradiation, the curable compound is cured. When the curable compound is polymerized by irradiation, the progress of this polymerization corresponds to the progress of curing.

  The curing device 84 may be provided in the casting device 10, the tenter 70, and the drying chamber 80 instead of downstream of the drying unit 62 as in the present embodiment. That is, you may irradiate an ultraviolet-ray with respect to any of the laminated body 22 which is a casting film, the wet film 64, and the dry film 82. FIG. In this manner, at least one of the laminate 22, the wet film 64, and the dry film 82 that is in the state of a cast film may be irradiated with ultraviolet rays.

  By the irradiation of the ultraviolet ray of the curing device 84, the portion corresponding to the casting film 22b derived from the polymerizable compound-containing composition and the portion corresponding to the casting film 22a derived from the initiator-containing composition are both cured. In this way, the polymer film 50 is obtained. And the obtained polymer film 50 is wound up by the winding core 88 set in the winding-up part 86 in roll shape.

<Step of forming a film having a cellulose ester layer at least at the air interface>
The method for producing a roll film of the present invention comprises at least an air interface comprising a cellulose ester layer comprising one layer or two or more layers and containing 2 to 20% by mass of a photopolymerization initiator based on the cellulose ester and the cellulose ester. The process (1) which forms the film which has is included.
In step (1), a composition for a base layer containing a polymer and a composition containing a cellulose ester and a photopolymerization initiator in an amount of 2 to 20% by mass based on the cellulose ester are successively cast or co-polymerized on a support. A step (1-1) of forming a film having a cellulose ester layer at least at an air interface by casting;
It is preferable to include a step (1-2) of peeling a film having a cellulose ester layer at least at the air interface from the support.

  It is preferable that the composition for base material layers containing a polymer does not contain an initiator. The term “initiator-free” for a base layer composition containing a polymer means that the initiator is not substantially contained in the base layer composition containing a polymer. Content with respect to the polymeric compound of an agent is less than 1 mass%. In the composition for a base layer containing the polymer, the content of the initiator with respect to the polymerizable compound is preferably less than 0.1% by mass, and more preferably less than 0.01% by mass.

It is preferable that the composition containing 2-20 mass% photopolymerization initiator with respect to cellulose ester and cellulose ester does not contain a polymerizable compound. Specifically, the composition containing 2 to 20% by mass of the photopolymerization initiator with respect to the cellulose ester and the cellulose ester preferably has a polymerizable compound content of less than 1% by mass with respect to the initiator. The content of the compound with respect to the initiator is more preferably less than 0.1% by mass, and particularly preferably less than 0.01% by mass.
The composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester and the cellulose ester may further contain another polymer.

  Hereinafter, the polymer, polymerizable compound, initiator, and other additives used in the method for producing a roll film of the present invention will be described.

(polymer)
In the method for producing a roll film of the present invention, the following cellulose acylate is preferably used as the cellulose ester of the cellulose ester layer, and the following polymer is preferably used as the polymer of the base material layer.

-Cellulose acylate-
In the method for producing a roll film of the present invention, the polymer of the base material layer is preferably a cellulose ester, and the polymer of the base material layer and the cellulose ester of the cellulose ester layer are more preferably cellulose acylate.
Cellulose acylate has a ratio of esterifying the hydroxyl group of cellulose with carboxylic acid, that is, the acyl group substitution degree (hereinafter referred to as acyl group substitution degree) satisfies all the conditions of the following formulas (1) to (3). Particularly preferred are: In (1) to (3), A and B are both acyl group substitution degrees, the acyl group in A is an acetyl group, and the acyl group in B has 3 to 22 carbon atoms.
2.5 ≦ A + B ≦ 3.0 (1)
0 ≦ A ≦ 3.0 (2)
0 ≦ B ≦ 2.9 (3)

  Glucose units constituting cellulose and having β-1,4 bonds have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer in which some or all of the hydroxyl groups of cellulose are esterified, and the hydrogen of the hydroxyl group is substituted with an acyl group having 2 or more carbon atoms. Since the degree of substitution is 1 when esterification of one hydroxyl group in the glucose unit is 100%, in the case of cellulose acylate, the hydroxyl groups at the 2nd, 3rd and 6th positions are each 100% ester. The degree of substitution is 3.

  Here, the total acyl group substitution degree obtained by “DS2 + DS3 + DS6”, where the acyl group substitution degree at the 2-position in the glucose unit is DS2, the acyl substitution degree at the 3-position is DS3, and the acyl substitution degree at the 6-position is DS6 is 2. It is preferably from 00 to 3.00, more preferably from 2.22 to 2.90, further preferably from 2.40 to 2.88, and from 2.60 to 2.88. Even more preferred. Furthermore, “DS6 / (DS2 + DS3 + DS6)” is preferably 0.32 or more, more preferably 0.322 or more, and further preferably 0.324 to 0.340.

  There may be only one kind of acyl group, or two or more kinds. When there are two or more acyl groups, it is preferable that one of them is an acetyl group. The sum of the substitution degrees of the hydrogen at the 2-, 3- and 6-position hydroxyl groups with acetyl groups is DSA, and the sum of the substitution degrees with acyl groups other than the acetyl groups at the 2-, 3- and 6-positions is DSB. In this case, the value of “DSA + DSB” is preferably 2.2 to 2.86, more preferably 2.40 to 2.88, and particularly preferably 2.60 to 2.88. DSB is preferably 1.50 or less, more preferably 0.5 or less, and particularly preferably 0. In DSB, 28% or more is preferably 6-position hydroxyl group substitution, more preferably 30% or more, further preferably 31% or more, particularly preferably 32% or more substitution of 6-position hydroxyl group. It is preferable. In addition, the value of “DSA + DSB” at the 6-position of cellulose acylate is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more. By using the cellulose acylate as described above, preferable solubility for obtaining a polymer solution used for solution casting can be obtained, and a polymer solution having a low filterability and a preferable viscosity can be produced. In particular, when a non-chlorine organic solvent is used, the above cellulose acylate is preferable.

  The acyl group having 2 or more carbon atoms may be an aliphatic group or an aryl group, and is not particularly limited. For example, there are cellulose alkylcarbonyl ester, alkenylcarbonyl ester, aromatic carbonyl ester, aromatic alkylcarbonyl ester, etc., and these may each further have a substituted group. Propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t-butanoyl group, cyclohexane Examples thereof include a carbonyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, and a cinnamoyl group. Among these, a propionyl group, a butanoyl group, a dodecanoyl group, an octadecanoyl group, a t-butanoyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, a cinnamoyl group, and the like are more preferable, and a propionyl group and a butanoyl group are particularly preferable.

  The polymerizable compound used in the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester should be used in the range of 50 to 200 parts by mass with respect to 100 parts by mass of the cellulose ester. Is preferable, more preferably in the range of 70 to 180 parts by mass, and particularly preferably in the range of 100 to 150 parts by mass.

(Initiator)
As the photopolymerization initiator, a known photopolymerization initiator or a known thermal polymerization initiator can be used. The density | concentration of a photoinitiator or a thermal-polymerization initiator is 2-20 mass% with respect to a cellulose ester in the composition containing a cellulose ester and a photoinitiator, It is preferable that it is 3-15 mass%, More preferably, it is 5-15 mass%.

  Photo radical polymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfides Examples include compounds, fluoroamine compounds and aromatic sulfoniums. Examples of acetophenones include 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxydimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone and 2 -Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone is included. Examples of benzoins include benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether. Examples of the benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

Various examples are described in the latest UV curing technology (P.159, issuer; Kazuhiro Takashiro, publisher; Technical Information Association, Inc., published in 1991), which is useful for the present invention.
Preferable examples of commercially available photocleavable photoradical polymerization initiators include Irgacure series (IrgOXE01, Irg127, Irg651, Irg184, Irg907) manufactured by BASF Corporation.
Further, as described in JP-A-6-41468, it is also preferably used in combination of two photopolymerization initiators.

In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Further, instead of or in addition to the photopolymerization initiator, a thermal polymerization initiator such as a thermal radical initiator may be used to cause the polymerization reaction by heating.

Examples of the thermal radical polymerization initiator include azo compounds and peroxides, with azo compounds being preferred. Examples of the azo compound include 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), and dimethyl-2,2′-. Azobis (2-methylpropionate), 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis [N- ( 2-propenyl) 2-methylpropionamide], 1-[(1-cyano-1-methylethyl) azo] formamide, 2,2′-azobis (N-butyl-2-methylpropionamide), 2,2 ′ -Azobis (N-cyclohexyl-2-methylpropionamide) and the like. Examples of commercially available azo compounds exemplified above include V-70, V-65, V-60, V-59, V-40, V-30, V-501, V-601, VE-073, and VA-080. , VA-086, VF-096, VAm-110, VAm-111, VA-044, VA-046B, VA-066, VA-061, V-50, VA-057, VA-067, VR-110 (or more And Wako Pure Chemical Industries, Ltd.).
Examples of the peroxide include t-butyl peroxybenzoate, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and the like. Examples of commercially available peroxides include Perbutyl Z, Perhexa 25B (manufactured by NOF Corporation), and the like.
Among these thermal radical polymerization initiators, those having a 10-hour half-life temperature of 20 to 150 ° C are preferred, those having 40 to 130 ° C are more preferred, those having 60 to 110 ° C are more preferred, and 70 ° C. What is -100 degreeC is especially preferable.

(Other additives)
The composition containing the cellulose ester used in the production method of the present invention and a thermal polymerization initiator in an amount of 2 to 20% by mass relative to the cellulose ester or the composition for a substrate layer not containing a photopolymerization initiator includes an ultraviolet absorber. (Hereinafter also referred to as UV absorber or UV agent), aromatic terminal ester compounds, other oligomers and polymers may be included.
Hereinafter, other additives used in the present invention will be described.

-UV absorber-
In the method for producing a roll film of the present invention, an ultraviolet absorber of 1% by mass or more is contained with respect to a polymer contained in a composition containing a thermal polymerization initiator or a composition for a substrate layer not containing a photopolymerization initiator. It is preferable to contain, it is more preferable to contain a 1.5-20 mass% ultraviolet absorber, and it is especially preferable to contain a 2-10 mass% ultraviolet absorber. The ultraviolet absorber contributes to improvement of the durability of the polarizer. In particular, in an embodiment in which a hard coat film described later using the roll film of the present invention is used as a surface protective film of a liquid crystal display device, the addition of an ultraviolet absorber is effective.
The method for producing a polymer film of the present invention comprises a composition containing a thermal polymerization initiator or a composition containing a photopolymerization initiator in an amount of 2 to 20% by mass based on the composition for a substrate layer not containing a photopolymerization initiator. Either one may contain an ultraviolet absorber, and the composition containing a thermal polymerization initiator or the composition for a substrate layer not containing a photopolymerization initiator preferably contains an ultraviolet absorber, and the photopolymerization initiator It is preferable from the viewpoint of increasing the reaction rate of the polymerizable compound that only the composition for the base layer containing no UV absorber contains the ultraviolet absorber.

  There is no restriction | limiting in particular about the ultraviolet absorber which can be used for this invention. Any ultraviolet absorber conventionally used in cellulose acylate films can be used. As an ultraviolet absorber, the compound as described in Unexamined-Japanese-Patent No. 2006-184874 can be mentioned. Polymer ultraviolet absorbers can also be preferably used. In particular, polymer type ultraviolet absorbers described in JP-A-6-148430 are preferably used.

  As an example, an ultraviolet absorber having the following structure is given, but the ultraviolet absorber to be added is not limited to the ultraviolet absorber having the following structure.

-Aromatic terminal ester compounds-
For the purpose of reducing the space (free volume) in which the cellulose ester molecular chain can move and improving the surface hardness, an aromatic terminal ester compound can be added. For example, an aromatic terminal ester compound represented by the following general formula can be added.
B- (GA) n-GB
(In the formula, B independently represents a benzene monocarboxylic acid residue. G independently represents an alkylene glycol residue having 2 to 12 carbon atoms, an aryl glycol residue having 6 to 12 carbon atoms, or 4 carbon atoms. Represents an oxyalkylene glycol residue having ˜12, A represents an alkylene dicarboxylic acid residue having 4 to 12 carbon atoms or an arylene dicarboxylic acid residue having 6 to 12 carbon atoms, and n represents an integer of 0 or more.)

  The aromatic terminal ester compound used has a number average molecular weight of preferably 300 to 2000, more preferably 500 to 1500. The acid value is preferably 0.5 mgKOH / g or less, the hydroxyl value is 25 mgKOH / g or less, more preferably the acid value is 0.3 mgKOH / g or less, and the hydroxyl value is 15 mgKOH / g or less.

Moreover, the compound represented by the following general formula can also be used preferably as an aromatic terminal ester type compound.

(Wherein R ^{1 to} R ⁷ and R ^{9 to} R ¹¹ each independently represent a hydrogen atom or a substituent, R ⁸ represents a hydrogen atom or a non-conjugated substituent, and X ¹ and X ² are Each independently represents a single bond or an aliphatic linking group, L represents a single bond, —N (R ¹² ) — or —C (R ¹³ ) (R ¹⁴ ) —, and R ^{12 to} R ¹⁴ are Each independently represents a hydrogen atom or a substituent.)

  Details of the above aromatic terminal ester compounds are described in paragraph numbers 0068 to 0116 of JP2013-127058A. This description is incorporated as part of this description.

-Other oligomers and polymers-
In order to impart brittleness to the polymer film of the present invention, other oligomers and / or polymers having a weight average molecular weight of 500 or more may be added.
Examples of other oligomers and polymers include cellulose-based and styrene-based polymers and polyester acrylates.
It is preferable that other oligomers and / or polymers in the roll film of the present invention are not included in the roll film of the present invention. When included in the roll film of the present invention, for example, it is preferably 5 to 80% by mass, more preferably 25 to 70% by mass, and particularly preferably 35 to 70% by mass with respect to the total mass of the roll film of the present invention. 65% by mass.

(solvent)
There is no particular limitation on the solvent used in the base layer composition containing the thermal polymerization initiator and the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester. Can be used. For example, it is preferable to use a known solvent used for solution casting of a cellulose ester film.
The composition for a base layer containing the thermal polymerization initiator used in the present invention and the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester form a dope, which is used as a support. It is preferable to cast it on top to form a film. At this time, since it is necessary to evaporate the solvent after casting, it is preferable to use a volatile solvent.
Furthermore, it does not react with a reactive metal compound or a catalyst, and does not dissolve the casting support. Two or more solvents may be mixed and used.
Here, an organic solvent having good solubility for the composition (a composition containing a photopolymerization initiator, a composition containing a thermal polymerization initiator, and another composition for forming a base material layer) is used. An organic solvent which is called a good solvent and has a main effect on dissolution and is used in a large amount among them is called a main (organic) solvent or a main (organic) solvent.

  Examples of good solvents include ketones such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethers such as tetrahydrofuran (THF), 1,4-dioxane, 1,3-dioxolane, 1,2-dimethoxyethane, and formic acid. In addition to esters such as methyl, ethyl formate, methyl acetate, ethyl acetate, amyl acetate, and γ-butyrolactone, methyl cellosolve, dimethylimidazolinone, dimethylformamide, dimethylacetamide, acetonitrile, dimethylsulfoxide, sulfolane, nitroethane, chloride Examples include methylene and methyl acetoacetate, and 1,3-dioxolane, THF, methyl ethyl ketone, acetone, methyl acetate and methylene chloride are preferred.

The dope preferably contains 1 to 40% by mass of an alcohol having 1 to 4 carbon atoms in addition to the organic solvent.
After casting the dope onto a metal support, the solvent starts to evaporate and the proportion of alcohol increases, so that the web (a composition containing a photopolymerization initiator on the support, a composition containing a thermal polymerization initiator) , And other dope of the composition for forming a base material layer, the dope film after the casting is referred to as a web or a cast film), and a gel that makes it easy to peel from a metal support When used as a solvating solvent, or when the proportion of these is small, it also has a role of promoting dissolution of a polymer of a non-chlorine organic solvent, and also has a role of suppressing gelation, precipitation, and increase in viscosity of a reactive metal compound.

Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol, and propylene glycol monomethyl ether.
Of these, methanol, ethanol, and n-butanol are preferred because they have excellent dope stability, have a relatively low boiling point, good drying properties, and are not toxic. Two or more alcohols having 1 to 4 carbon atoms may be used in combination, and in the production method of the present invention, a combination of methanol and n-butanol is most preferable from the viewpoints of solubility and gelation. When a cellulose ester is used as a polymer, these organic solvents alone are not soluble in the cellulose ester and are referred to as poor solvents.

When cellulose ester is used as the polymer in the present invention, the cellulose ester that is a raw material for the cellulose ester contains hydrogen bonding functional groups such as hydroxyl groups, esters, and ketones, and is therefore preferably 5 to 30% by mass in the total solvent. Is preferably 7 to 25% by mass, more preferably 10 to 20% by mass, from the viewpoint of reducing the peeling load from the casting support.
Further, in the present invention, it is effective to contain a small amount of water to increase the solution viscosity and the film strength in the wet film state at the time of drying, or to increase the dope strength at the time of casting the drum method. It may be contained in an amount of 0.1 to 5% by mass, more preferably 0.1 to 3% by mass, and particularly 0.2 to 2% by mass.

  Examples of combinations of organic solvents preferably used as the solvent for the polymer solution in the present invention are described in JP-A-2009-262551.

  In addition, if necessary, a non-halogen organic solvent can be used as a main solvent, and detailed description can be found in the Japan Institute of Invention Publication (Publication No. 2001-1745, published on March 15, 2001, Invention Association). There is a description.

In the production method of the present invention, the solvent of the composition for the base layer containing the polymer and the solvent of the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester and the cellulose ester have the same composition ratio. Although different composition ratios may be used, the same composition ratio is preferable.
Among them, in the present invention, the combination of the base layer composition containing the polymer and the solvent of the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester is within the following range. Is preferable from the viewpoint of adjusting the viscosity during co-casting.
Solvent of base layer composition containing polymer: Mixed solvent of methylene chloride and methanol Solvent of composition containing 2-20% by mass of photopolymerization initiator based on cellulose ester and cellulose ester: Mixture of methylene chloride and methanol solvent

The polymer concentration in the composition for a base layer containing the polymer in the present invention and the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester is preferably 5 to 40% by mass. -30 mass% is more preferable, and 15-30 mass% is the most preferable.
The polymer concentration can be adjusted to a predetermined concentration when the polymer is dissolved in a solvent. Further, after preparing a solution with a low concentration (for example, 4 to 14% by mass) in advance, the solution may be concentrated by evaporating the solvent or the like. Furthermore, after preparing a high concentration solution in advance, it may be diluted. Moreover, the concentration of the polymer can be lowered by adding an additive.

Further, the solid content concentration of the composition for the base material layer containing the polymer and the solid content concentration of the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester and the cellulose ester are different even if they are the same. It may be. Among them, in the present invention, the solid content concentration of the composition for a base layer containing the polymer, the cellulose ester and the composition containing 2 to 20% by mass of the photopolymerization initiator based on the cellulose ester is in the following range. Is preferable from the viewpoint of adjusting the viscosity during co-casting.
The solid content concentration of the base layer composition containing a polymer is preferably 15 to 45 mass%, more preferably 25 to 35 mass%.
Composition solid content concentration containing 2-20 mass% photopolymerization initiator with respect to cellulose ester and cellulose ester: 10-40 mass% is preferable, and 20-30 mass% is more preferable.

  The timing of adding the additive can be appropriately determined according to the type of the additive. For example, the UV absorber is added to the dope after dissolving the UV absorber in an alcohol such as methanol, ethanol, butanol, an organic solvent such as methylene chloride, methyl acetate, acetone, dioxolane, or a mixed solvent thereof, or You may add directly in dope composition. For an inorganic powder that does not dissolve in an organic solvent, it is preferable to use a dissolver or a sand mill in the organic solvent and the cellulose ester to disperse them before adding them to the dope.

(Dissolution process)
The step of forming the composition dope for the base material layer containing the polymer by dissolving the polymer and the additive in an organic solvent mainly containing a good solvent for the polymer while stirring, or mixing the additive solution with the polymer solution And forming a dope.
It is preferable that the dope is similarly formed in the composition containing 2 to 20% by mass of the photopolymerization initiator with respect to the cellulose ester and the cellulose ester.
For the dissolution of the polymer, a method carried out at normal pressure, a method carried out below the boiling point of the main solvent, a method carried out under pressure above the boiling point of the main solvent, JP-A-9-95544, JP-A-9-95557, or Various dissolution methods such as a method using a cooling dissolution method as described in JP-A-9-95538 and a method using a high pressure as described in JP-A-11-21379 can be used. A method in which pressure is applied as described above is preferable.
The concentration of the polymer in the dope is preferably 10 to 35% by mass. It is preferable that an additive is added to the dope during or after dissolution to dissolve and disperse, and then filtered through a filter medium, defoamed, and sent to the next step with a liquid feed pump.

(Casting process)
In the present invention, a composition for a base layer containing a polymer and a composition containing a cellulose ester and a photopolymerization initiator in an amount of 2 to 20% by mass based on the cellulose ester are successively or co-cast on a support. It is preferable to include a step (1-1) of forming a film having a cellulose ester layer at least at the air interface. In the casting process, the dope is fed to a pressure die through a liquid feed pump (for example, a pressurized metering gear pump), and an endless metal belt such as a stainless steel belt or a rotating metal drum or the like is supported infinitely. It is preferable that the dope is cast from the pressure die slit at the casting position on the (preferably metal support).
A pressure die that can adjust the slit shape of the die base and facilitates uniform film thickness is preferred. The pressure die includes a coat hanger die and a T die, and any of them is preferably used. The surface of the metal support is preferably a mirror surface. In order to increase the film forming speed, two or more pressure dies may be provided on a support (preferably a metal support), and the dope amount may be divided and stacked. Or it is also preferable to obtain the film of a laminated structure by the co-casting method which casts several dope simultaneously. As a co-casting, sequential casting, or a method of casting and coating, the contents described in JP2011-13296A can be used, and the contents described in this gazette are incorporated in the present invention. Among these, the co-casting method is preferable from the viewpoint of suppressing air entrained between the polymerized compound-containing layer and the initiator-containing layer during casting.

  In the simultaneous co-casting method (multi-layer simultaneous casting), the casting dope of each layer (which may be two layers or more) is simultaneously applied from another slit or the like on the casting support (band or drum). This is a casting method in which a dope is extruded from a casting caster to be extruded, and each layer is cast simultaneously, peeled off from a support at an appropriate time, and dried to form a film. FIG. 2 of Japanese Patent Application Laid-Open No. 2011-132396 discloses an embodiment in which a co-casting giusa is used to simultaneously extrude and cast a surface layer dope and a core layer dope on a casting metal support. But it can also be used.

  In the sequential casting method, a dope for an outermost layer is first extruded from a casting giusa on a casting support, cast, and dried or dried without being dried or dried. The dope for casting is extruded from a casting beam caster, and if necessary, the dope is cast and laminated sequentially up to the third layer or more, peeled off from the support at an appropriate time, and dried to form a film. The casting method.

In the method for producing a roll film of the present invention, the laminate may be formed to be two layers or may be formed to be three or more layers, but the laminate is formed to be two layers. Is preferred.
In the manufacturing method of the polymer film of this invention, it has a cellulose-ester layer containing 2-20 mass% photoinitiator with respect to a cellulose ester and a cellulose ester at least in an air interface.

(Solvent evaporation process)
In the process of heating the web (previously finished polymer film and still containing a lot of solvent) on the support, and evaporating the solvent until the web can be peeled from the support. is there.
In order to evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the support by a liquid, a method of transferring heat from the front and back by radiant heat, and the like. The drying efficiency is preferable. A method of combining them is also preferable. In the case of backside liquid heat transfer, it is preferable to heat at or below the boiling point of the main solvent of the organic solvent used in the dope or the organic solvent having the lowest boiling point.

(Peeling process)
In this invention, it is preferable to include the process (1-2) which peels from the support body the film which has a cellulose-ester layer at an air interface at least.
In this step, the web on which the solvent has evaporated on the support is peeled at the peeling position. The peeled web is sent to the next process. It should be noted that if the residual solvent amount of the web at the time of peeling (the following formula) is too large, peeling is difficult, or conversely, if the film is peeled off after being dried sufficiently on the support, a part of the web is peeled off in the middle. Or
Here, there is a gel casting method (gel casting) as a method for increasing the film forming speed (the film forming speed can be increased by peeling while the residual solvent amount is as large as possible). For example, there are a method in which a poor solvent for the polymer is added to the dope and the gel is formed after casting the dope, a method in which the temperature of the support is lowered and the gel is formed. By making it gel on the support and increasing the strength of the film at the time of peeling, it is possible to speed up the peeling and increase the film forming speed.
The amount of residual solvent at the time of peeling of the web on the metal support is preferably peeled in a range of 5 to 150% by mass depending on the strength of drying conditions, the length of the support, etc., but when the amount of residual solvent is larger In the case of peeling, the amount of residual solvent at the time of peeling is determined in consideration of the economic speed and quality. In the present invention, the temperature at the peeling position on the metal support is preferably -50 to 40 ° C, more preferably 10 to 40 ° C, and most preferably 15 to 30 ° C.

Further, the residual solvent amount of the web at the peeling position is preferably 10 to 150% by mass, and more preferably 10 to 120% by mass.
The amount of residual solvent can be represented by the following formula.
Residual solvent amount (% by mass) = [(MN) / N] × 100
Here, M is the mass of the web at an arbitrary point in time, and N is the mass when the mass M is dried at 110 ° C. for 3 hours.

(Drying or heat treatment process, stretching process)
After the peeling step, the web may be dried using a drying device that alternately passes the web through rolls arranged in the drying device and / or a tenter device that clips and transports both ends of the web with clips. preferable.

When performing heat treatment in the present invention, the heat treatment temperature is less than Tg-5 ° C, preferably Tg-20 ° C or more and less than Tg-5 ° C, more preferably Tg-15 ° C or more and less than Tg-5 ° C. preferable.
The heat treatment temperature is preferably 30 minutes or less, more preferably 20 minutes or less, and particularly preferably about 10 minutes.

  As a means for drying and heat treatment, hot air is generally blown on both sides of the web, but there is also a means for heating by applying a microwave instead of the wind. The temperature, air volume, and time vary depending on the solvent used, and the conditions may be appropriately selected according to the type and combination of the solvents used.

(Take-up)
The manufacturing method of the roll-shaped film of this invention includes the process (2) which winds up a film in roll shape and forms a roll-shaped film.
The length of the polymer film obtained as described above is preferably wound at 100 to 10000 m per roll, more preferably 500 to 7000 m, and further preferably 1000 to 6000 m. The width of the film is preferably 0.5 to 5.0 m, more preferably 1.0 to 3.0 m, and still more preferably 1.0 to 2.5 m. When winding, it is preferable to give knurling to at least one end, the knurling width is preferably 3 mm to 50 mm, more preferably 5 mm to 30 mm, and the height is preferably 0.5 to 500 μm, more preferably 1 to 200 μm. is there. This may be a single push or a double push.
The web thus obtained can be wound up to obtain a roll film.

(Stretching)
Although an extending process may be performed before hardening a laminated body or after hardening, it is preferable from a viewpoint of raising the surface hardness of the polymer film obtained by performing before hardening.
The stretching step may be performed on the support before peeling the laminate from the support or after the laminate is peeled from the support, but preferably after the laminate is peeled from the support. .
The stretching step is preferably performed before the laminate is completely dried.

  The stretching process may be performed in one direction of MD and TD, or may be biaxially stretched in both directions. Stretching in the TD direction is preferred. Stretching may be performed in one stage or in multiple stages.

The stretching ratio in stretching in the film transport direction MD is preferably 0 to 20%, more preferably 0 to 15%, and particularly preferably 0 to 10%. The stretch ratio (elongation) of the web during stretching can be achieved by the difference in peripheral speed between the metal support speed and the stripping speed (stripping roll draw). For example, when an apparatus having two nip rolls is used, the film can be preferably stretched in the conveying direction (longitudinal direction) by increasing the rotational speed of the nip roll on the outlet side rather than the rotational speed of the nip roll on the inlet side. it can. By performing such stretching, the tensile modulus of MD can be adjusted.
Here, the “stretch ratio (%)” means that obtained by the following formula.
Stretch ratio (%) = 100 × {(Length after stretching) − (Length before stretching)} / Length before stretching

The stretching ratio in stretching in the direction TD perpendicular to the film conveying direction is preferably 0 to 30%, more preferably 1 to 20%, and particularly preferably 2 to 15%.
In addition, in this invention, it is preferable to extend | stretch using a tenter apparatus as a method of extending | stretching to the direction TD orthogonal to a film conveyance direction.

  In the case of biaxial stretching, a desired retardation value can be obtained by relaxing the length in the longitudinal direction, for example, 0.8 to 1.0 times. The draw ratio is set according to various purposes. When producing a polymer film, it can also be uniaxially stretched in the longitudinal direction.

  It is preferable for the temperature during stretching to be Tg or less because the tensile elastic modulus in the stretching direction increases. In addition, Tg of a cellulose triacetate is about 130-140 degreeC. The stretching temperature is preferably Tg-90 ° C to Tg, and more preferably Tg-80 ° C to Tg-5 ° C.

(Dry)
When drying after the stretching step, the drying temperature, the amount of drying air and the drying time differ depending on the solvent used, and the drying conditions may be appropriately selected according to the type and combination of the solvents used. In the present invention, the drying temperature after the stretching step is preferably lower than the stretching temperature in the stretching step from the viewpoint of increasing the front contrast when the polymer film is incorporated into a liquid crystal display device.

(Shading)
When manufacturing the light-shielded roll-shaped film in this invention, the process (3 which light-shields a roll-shaped film using the shielding material whose transmittance | permeability of UV light with a wavelength range of 200-450 nm is 0.1% or less further. )including.
Thereby, the light-shielded roll-shaped film of this invention can be manufactured.

[Method for producing hard coat film with light-shielded roll film]
The first aspect of the method for producing a hard coat film of the present invention is a hard coat containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the light-shielded roll film of the present invention. A step (4A) of applying the layer forming composition and a step (5) of photocuring the hard coat layer forming composition are included.
The 2nd aspect of the manufacturing method of the hard coat film of this invention is a cellulose-ester layer which consists of 1 layer or 2 layers or more and contains 2-20 mass% photoinitiator with respect to a cellulose ester and a cellulose ester. Forming a film having at least an air interface (1), applying a hard coat layer-forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer (4B), and hard Including a step (5) of photocuring the composition for forming a coat layer, and a step in an environment where UV light in a wavelength band of 200 to 450 nm is shielded from the start of the step (1) to the end of the step (4B). (1) and a process (4B) are performed.
In the second aspect of the method for producing a hard coat film of the present invention, the process (in an environment in which UV light having a wavelength band of 200 to 450 nm is shielded from the start of the process (1) to the completion of the process (4B) ( The method for performing 1) and step (4B) is not particularly limited. For example, step (1) and step (4B) are performed inside a room in which only a fluorescent lamp provided with a UV cut filter is installed as illumination. A method can be mentioned.

[Method for producing hard coat film with roll film containing thermal polymerization initiator]
In the third aspect of the method for producing a hard coat film of the present invention, a polymerizable monomer and a photopolymerization initiator are provided on the cellulose ester layer of the film obtained by unwinding the roll film containing the thermal polymerization initiator of the present invention. A step (4S) of applying a hard coat layer forming composition, a step (5) of photocuring the hard coat layer forming composition, and a step (6) of thermosetting the hard coat layer forming composition. Including.
The fourth aspect of the method for producing a hard coat film of the present invention is a film comprising one layer or two or more layers, and having at least an air interface with a cellulose ester layer containing a cellulose ester and a thermal polymerization initiator with respect to the cellulose ester. A step (4S) of forming a hard coat layer forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer (1S), and a hard coat layer forming composition A step (5) of photocuring, and a step (6) of thermosetting the composition for forming a hard coat layer.

<Application of composition for forming hard coat layer>
In the method for producing a hard coat film of the present invention, a hard coat layer is further laminated on the cellulose ester layer. In addition, an antiglare layer and an antireflection layer may be laminated.

  The hard coat layer is preferably formed by curing a composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator. The composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator is preferably prepared as a liquid coating composition. An example of the coating composition contains a matrix-forming binder monomer or oligomer, polymers, and an organic solvent. A hard coat layer can be formed by curing the coating composition after coating. For curing, a crosslinking reaction or a polymerization reaction can be used.

(Monomer or oligomer for matrix forming binder)
Examples of matrix forming binder monomers or oligomers that can be used include ionizing radiation curable polyfunctional monomers and polyfunctional oligomers. The polyfunctional monomer or polyfunctional oligomer is preferably a monomer capable of crosslinking reaction or polymerization reaction. The functional group of the ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.

  Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as (meth) acryloyl group, vinyl group, styryl group, and allyl group, and ring-opening polymerizable functional groups such as epoxy compounds. Of these, a (meth) acryloyl group is preferred.

As a specific example of a photopolymerizable polyfunctional monomer having a photopolymerizable functional group,
(Meth) acrylic acid diesters of alkylene glycol such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, propylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyoxyalkylene glycols such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate;
(Meth) acrylic acid diesters of ethylene oxide or propylene oxide adducts such as 2,2-bis {4- (acryloxy-diethoxy) phenyl} propane and 2,2-bis {4- (acryloxy-polypropoxy) phenyl} propane ;
Etc.

  Furthermore, urethane (meth) acrylates, polyester (meth) acrylates, isocyanuric acid acrylates, and epoxy (meth) acrylates are also preferably used as the photopolymerizable polyfunctional monomer.

Among the above, esters of polyhydric alcohol and (meth) acrylic acid are preferable, and polyfunctional monomers having three or more (meth) acryloyl groups in one molecule are more preferable.
Specifically, (di) pentaerythritol tri (meth) acrylate, (di) pentaerythritol tetra (meth) acrylate, (di) pentaerythritol penta (meth) acrylate, (di) pentaerythritol hexa (meth) acrylate, tri Pentaerythritol triacrylate, tripentaerythritol hexatriacrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri (meth) acrylate, EO-modified tri (meth) acrylate phosphate, 1,2,4-cyclohexanetetra (meth) acrylate, Printer glycerol triacrylate, 1,2,3-cyclohexane tetramethacrylate, polyester polyacrylate and caprolactone-modified tris (acryloyloxyethyl) isocyanurate, and the like.
In the present specification, “(meth) acrylate”, “(meth) acrylic acid”, and “(meth) acryloyl” represent “acrylate or methacrylate”, “acrylic acid or methacrylic acid”, and “acryloyl or methacryloyl”, respectively. .

Furthermore, resins having three or more (meth) acryloyl groups, such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins And oligomers or prepolymers such as polyfunctional compounds such as polyhydric alcohols.
As specific compounds of polyfunctional acrylate compounds having three or more (meth) acryloyl groups, JP-A-2007-256844 [0096] and the like can be referred to.

As urethane acrylates, for example, alcohols, polyols, and / or hydroxyl group-containing compounds such as hydroxyl group-containing acrylates are reacted with isocyanates, and if necessary, polyurethane compounds obtained by these reactions (meth) Mention may be made of urethane acrylate compounds obtained by esterification with acrylic acid.
As specific examples of specific compounds, reference can be made to the description of [0017] in JP-A-2007-256844.

  Examples of the isocyanuric acid acrylates include isocyanuric acid diacrylates and isocyanuric acid triacrylates, and specific examples of compounds refer to JP-A-2007-256844 [0018] to [0021]. be able to.

  In the hard coat layer, an epoxy compound can be further used for reducing shrinkage due to curing. As monomers having an epoxy group for constituting this, monomers having two or more epoxy groups in one molecule are used, and examples thereof include JP-A Nos. 2004-264563, 2004-264564, and Examples thereof include epoxy monomers described in 2005-37737, 2005-37738, 2005-140862, 2005-140862, 2005-140863, 2002-322430 and the like. It is also preferable to use a compound having both epoxy and acrylic functional groups such as glycidyl (meth) acrylate.

-Multi-branched compounds-
The polymerizable compound-containing composition or initiator-containing composition used in the production method of the present invention preferably contains a multi-branched compound in addition to the polyfunctional acrylate, and contains a polymerizable multi-branched compound described later. It is more preferable. Thereby, the cured film which has still higher hardness is obtained.

The hyperbranched compound is a compound having a molecular weight of 1300 or more having a high-order branched structure having a partial structure such as a comb shape or a star shape repeatedly in two or more stages. Multibranched compounds include those whose terminal group is a group selected from a carboxyl group, an amino group, an epoxy group, an acryloyl group, and a methacryloyl group. Among these, a particularly preferred terminal group is an acryloyl group or a methacryloyl group. Hereinafter, a compound having a molecular weight of 1300 or more having at least one group selected from an acryloyl group and a methacryloyl group (hereinafter, these groups are also collectively referred to as “(meth) acryloyl group”) as a terminal group is referred to as “polymerizable”. Also referred to as “multi-branched compound”. )
The hyperbranched compound is preferably a polymerizable hyperbranched compound. The polymerizable multi-branched compound preferably has at least 10 terminal (meth) acryloyl groups, more preferably 12 or more and 32 or less.
The hyperbranched compound is a compound having a molecular weight of 1300 or more, but the molecular weight is 1300 or more and 100,000 or less, more preferably 1300 or more and 20000 or less, and particularly preferably 1300 or more and 15000 or less. When it has a molecular weight of 1300 or more, it means a weight average molecular weight.

In the present invention, it is preferable that the multi-branched compound is selected from the group consisting of dendrimers and hyperbranched polymers because a cured film having high hardness can be easily obtained.
A dendrimer has a chemical structure in which a chemical structure constituting a core (hereinafter also referred to as “core part”) is regularly branched to the outside thereof, and has a spherical, highly controlled chemical structure and Has a molecular weight. Hyperbranched polymers have a chemical structure similar to dendrimers, but are not as highly regular branching structures or high molecular weight controls as in dendrimers, and the branches are formed according to a probability distribution and have a broad molecular weight distribution. I have it.
Dendrimers and hyperbranched polymers have excellent solubility, low viscosity when made into a solution, and have a large number of functional groups (for example, carboxyl group, amino group, epoxy group, acryloyl group, and methacryloyl group). Such a characteristic on the chemical structure seems to be a factor for obtaining a cured film having a high hardness at a low heating temperature by combination with a polymerizable compound.

Dendrimers and hyperbranched polymers are described in, for example, Japanese Patent Application Laid-Open No. 2012-173549, International Publication No. 2008-047620, Japanese Patent Application Laid-Open No. 2012-83594, and the like. These compounds have a core part, a branched chain part bonded to the core part, and a terminal group further bonded to the branched chain part. The branched chain portion includes a highly branched structure in which a two-dimensional or three-dimensional branched partial structure is repeated two or more steps, and the terminal group has a large number of functional groups (for example, a hydroxy group, a carboxyl group, an amino group). , Epoxy group, acryloyl group, and methacryloyl group). Such dendrimers and hyperbranched polymers are dendritic compounds having a molecular weight of 1300 or more.
The compound constituting the core is preferably synthesized using a branched polyhydric alcohol having three or more chain groups having a methylol group at the end, and further having a chain shape having a methylol group at the end. Those synthesized using a branched polyhydric alcohol having 4 or more groups are particularly preferred.
Preferable specific examples of the polyhydric alcohol include, for example, pentaerythritol, dipentaerythritol, trimethylolpropane and the like. A structure in which branching is repeated by connecting a linking group having a branched structure (hereinafter also referred to as a branched chain portion) to the hydroxy group of the polyhydric alcohol in two or more stages. That is, a branched chain part is bonded to each branched chain end of the branched structure closest to the hydroxy group of the polyhydric alcohol to form a highly branched compound, and at least a part of the functional group described above is formed at the terminal. Are combined. When a group other than a functional group is included at the terminal, these groups include an alkyl group such as a methyl group.
Examples of the core part include structural units represented by the following structures (1) to (4).

[In structure (1), * part represents a binding site with a branched chain part. ]

[In structure (2), n represents an integer of 0 to 2, and * part has the same meaning as * described above. ]

[In structure (3), * part has the same meaning as * above. ]

[In structure (4), * part has the same meaning as * above. ]

  The branched chain portion is preferably a structural unit having three or more branched structures, and examples thereof include polyamide, polyester, polyether, polyurethane, and polyurea. Of these, polyester units and polyurethane units are preferred. As the branched chain part, a polyhydroxycarboxylic acid unit is preferable, and a unit represented by the following structure (5) or structure (6) is more preferable. Further, the branched chain portion may include a structure in which two or more units represented by the following structure (5) or structure (6) are independently connected.

[In structure (5), * part represents a binding site with a core part or a branched chain unit. ]

〔構造（６）中、＊部はコア部又は分岐鎖部単位との結合部位を表す。〕

[In structure (6), * part represents a binding site with a core part or a branched chain unit. ]

  The core portion and the branched chain portion may be bonded by a single bond, or may be bonded via a bonding site derived from an alkylene oxide such as ethylene oxide or propylene oxide. In the case of bonding via a bonding site derived from alkylene oxide, it is preferable that the oxygen terminal side of alkylene oxide is bonded to the branched chain part * part.

  The group bonded to the terminal of the multi-branched compound is preferably a group having an ethylenically unsaturated bond, and examples of such a group include a (meth) acryloyl group and a vinyloxy group. Of these, a (meth) acryloyl group is preferable.

  Further, the alkali-developable multi-branched polymer described in International Publication No. 2008-047620 is more advantageous for pattern formation by alkali development because of its increased solubility before curing by radiation.

These compounds can be produced, for example, by a method described in International Publication No. 2008/047620 pamphlet or Japanese Patent Application Laid-Open No. 2008-174518.
The molecular weight or the weight average molecular weight of these compounds is 1300 or more and 100,000 or less, more preferably 1300 or more and 20000 or less, further preferably 1300 or more and 15000 or less. The viscosity at 25 ° C. is preferably 100 Pa · s to 500,000 Pa · s, more preferably 300 to 300,000 Pa · s.

  Specific examples include compounds represented by the following structural formulas (B-1) to (B-5).

  In addition, Esdrimer HU-22 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Biscote # 1000 (manufactured by Osaka Organic Chemical Co., Ltd.), STAR-501 (manufactured by Osaka Organic Chemical Co., Ltd.), A-HBR-5 (Shin Nakamura Chemical Co., Ltd.), New Frontier R-1150 (Daiichi Kogyo Seiyaku Co., Ltd.), SN-2301 (Sartomer Co., Ltd.), Nissan Chemical Industries, Ltd. Products sold in Japan, such as UR-101 can be used. The compounds selected from the group consisting of these dendrimers and hyperbranched polymers may be used alone or in combination of two or more.

(Polymer compound)
The hard coat layer may contain a non-curable polymer compound. The explanation and preferred specific examples of the polymer compound are the same as those described in JP 2012-215812 A, and the contents described in this gazette are incorporated in the present specification.

(Curable composition)
Description and preferred specific examples of the curable composition that can be used for forming the hard coat layer are the same as those described in JP 2012-215812 A, and the contents described in this gazette are described in this specification. Incorporated.

<Curing>
The manufacturing method of the hard coat film of this invention includes the process (5) of photocuring the composition for hard-coat layer formation.
As for the process of photocuring the composition for hard-coat layer formation, it is more preferable that a hardening process is a process of irradiating a composition for hard-coat layer formation 1 time or more with an ultraviolet-ray.
Examples of the ultraviolet irradiation source include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, a carbon arc, a metal halide lamp, and sunlight. Photopolymerization by irradiation with ultraviolet rays can be performed in air or an inert gas, but in the case of using an ethylenically unsaturated monomer, it may be in air, but oxygen may be used as much as possible to shorten the induction period of polymerization. A gas with a low concentration is preferred. The irradiation intensity of the ultraviolet rays to be irradiated is preferably about 0.1 to 100 mW / cm ² , and the irradiation amount is preferably about 100 to 20000 mJ / cm ² .

The method for producing a hard coat film of the present invention may include a step (6) of thermosetting the composition for forming a hard coat layer. In particular, when the cellulose ester layer on which the hard coat layer is laminated contains a thermal polymerization initiator, the step (5) of photocuring the hard coat layer forming composition and the hard coat layer forming composition are heated. It is preferable to include the step (6) of curing. Usually, after performing the process (5) of photocuring the composition for forming a hard coat layer, the process (6) of thermally curing the composition for forming a hard coat layer is performed.
The process (6) for thermosetting the hard coat layer forming composition is not particularly limited as long as it is carried out in an environment in which the hard coat layer forming composition is thermally cured.

[Hard coat film]
The first aspect of the hard coat film of the present invention is for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the light-shielded roll film of the present invention. After the composition is applied, it is formed by photocuring.
The second aspect of the hard coat film of the present invention comprises one layer or two or more layers in an environment where UV light having a wavelength band of 200 to 450 nm is shielded, and 2 to 2 for cellulose ester and cellulose ester. After the composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator is applied on at least the cellulose ester layer of a film having a cellulose ester layer containing 20% by mass of a photopolymerization initiator at the air interface It is formed by photocuring.
The hard coat film of the present invention is preferably excellent in surface hardness. Specifically, when a pencil hardness test as an index of surface hardness is carried out, it is preferable to achieve 2H or higher, more preferably 3H or higher, still more preferably 4H or higher, 5H It is particularly preferable to achieve the above.
Moreover, the hard coat film of this invention can be manufactured with the manufacturing method of the hard coat film of this invention.
The thickness of the hard coat film of the present invention obtained by the method for producing a hard coat film is preferably 20 to 100 μm, and more preferably 20 to 70 μm. Furthermore, it is preferable that the thickness of the polymer film not including the hard coat layer is 20 to 60 μm. From the viewpoint of further thinning, the thickness of the polymer film not including the hard coat layer is more preferably 20 to 40 μm.

The hard coat film of the present invention may further have an antiglare layer and an antireflection layer.
The hard coat layer is preferably excellent in surface hardness. Specifically, the polymer film of the present invention having a hard coat layer preferably achieves 2H or higher, and more preferably achieves 3H or higher, when a pencil hardness test as an index of surface hardness is performed. .
The hard coat layer preferably has a thickness of 0.1 to 10 μm, more preferably 3 to 7 μm. By having a thin hard coat layer in the above-described range, an optical film including a hard coat layer that has improved physical properties such as brittleness and curl suppression, reduced weight, and reduced manufacturing cost is obtained.
The hard coat layer used in the present invention is a layer for imparting hardness and scratch resistance to the optical film. A hard-coat layer can be formed by apply | coating a coating composition on a base film (optical film), and making it harden | cure, for example. Moreover, you may laminate | stack another functional layer on a hard-coat layer for the purpose of adding another function. Also, by adding fillers and additives to the hard coat layer, chemical performance such as mechanical, electrical and optical physical performance and water / oil repellency can be imparted to the hard coat layer itself. .

[Polarizer]
Next, the aspect which uses the hard coat film of this invention as a protective film of a polarizing plate is demonstrated.
The polarizing plate of the present invention has a polarizer and the hard coat film of the present invention. An example of the polarizing plate of this invention consists of a polarizer and two polarizing plate protective films (transparent film) which protect both surfaces, and has the hard coat film of this invention as at least one polarizing plate protective film.
Since the hard coat film of the present invention has high surface hardness, it is particularly preferably used as a polarizing plate protective film on the viewing side of the upper polarizing plate disposed on the viewing side with respect to the liquid crystal cell.

  As the polarizing plate protective film on the side where the hard coat film of the present invention is not used, a retardation film is preferably used, and as such a retardation film, various additives are blended or stretched in a cellulose acylate film. Examples thereof include a retardation film that exhibits a desired retardation, and a retardation film that has an optically anisotropic layer made of a liquid crystal composition on the surface of a support. Specifically, the description of JP-A-2008-262161 can be referred to, and the contents thereof are incorporated in the present specification.

  As the polarizer, for example, a film obtained by immersing and stretching a polyvinyl alcohol film in an iodine solution can be used. When using a polarizer in which a polyvinyl alcohol film is immersed in an iodine solution and stretched, the surface-treated surface of the cellulose acylate film of the present invention can be directly bonded to at least one surface of the polarizer using an adhesive. . As the adhesive, an aqueous solution of polyvinyl alcohol or polyvinyl acetal (for example, polyvinyl butyral) or a latex of a vinyl-based polymer (for example, polybutyl acrylate) can be used. A particularly preferred adhesive is an aqueous solution of fully saponified polyvinyl alcohol.

The method of laminating the hard coat film of the present invention to the polarizer may be such that the transmission axis of the polarizer and the slow axis of the polymer film of the present invention used as a polarizing plate protective film are substantially parallel. preferable. The slow axis can be measured by various known methods, for example, using a birefringence meter (KOBRA DH, manufactured by Oji Scientific Instruments).
Here, being substantially parallel means that the deviation between the direction of the main refractive index nx of the hard coat film and the direction of the transmission axis of the polarizing plate is within 5 °, preferably within 1 °. Is preferably within 0.5 °. If the deviation is within 1 °, the polarization degree performance under the polarizing plate crossed Nicol is unlikely to deteriorate, and light leakage is not likely to occur.

<Functionalization of polarizing plate>
The polarizing plate of the present invention is provided with functional layers such as an antireflection film, a brightness enhancement film, a forward scattering layer, and an antiglare (antiglare) layer for improving the visibility of the display without departing from the spirit of the present invention. It is also preferably used as a functionalized polarizing plate combined with an optical film. Details of these can be referred to the descriptions in paragraphs 0229 to 0242, paragraphs 0249 to 0250, and paragraphs 0086 to 0103 in JP 2012-215812 A, and the contents thereof are incorporated in the present specification. .

[Liquid Crystal Display]
The liquid crystal display device of the present invention includes a liquid crystal cell and the hard coat film of the present invention or the polarizing plate of the present invention. Details of the liquid crystal display device can be referred to the description in paragraphs 0251 to 0260 of JP2012-082235A, and the contents thereof are incorporated in the present specification.

The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.
Example 6 is a reference example.

[Preparation of various solutions]
(Preparation of cellulose triacetate solution)
A cellulose triacetate powder (average size 2 mm) was gradually added to a stainless steel dissolution tank having stirring blades while thoroughly stirring the following solvent mixed solution to prepare a dope. After the addition, the mixture was allowed to stand at room temperature (25 ° C.) for 1 hour and at 35 ° C. for 2 hours to swell the cellulose triacetate. In addition, methanol, ethanol, and methylene chloride, which are solvents, all had a water content of 0.2% by mass or less.

-Preparation of initiator-containing cellulose ester solution-
The following composition was put into a mixing tank and stirred to dissolve each component to prepare an initiator-containing cellulose ester solution having a solid content concentration of 16% by mass.
―――――――――――――――――――――――――――――――――――
Triacetylcellulose (total acyl substitution degree 2.83, 6-position acylation substitution degree 0.93, 2,3-position acylation substitution degree 1.90, viscosity average polymerization degree 320, water content 0.4 mass %, Viscosity of 305 mPa · s of 6% by mass in methylene chloride solution)
100 parts by mass IRGACURE 127 (manufactured by BASF: polymerization initiator) 10 parts by mass Methylene chloride (first solvent) 598.1 parts by mass Methanol (second solvent) 89.4 parts by mass ------ ――――――――――――――――――――――――

-Preparation of cellulose ester solution for substrate layer-
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose ester solution for a base material layer having a solid content concentration of 16% by mass.
―――――――――――――――――――――――――――――――――――
Triacetylcellulose (total acyl substitution degree 2.83, 6-position acylation substitution degree 0.93, 2,3-position acylation substitution degree 1.90, viscosity average polymerization degree 320, water content 0.4 mass %, Viscosity of 305 mPa · s of 6% by mass in methylene chloride solution)
100 parts by mass UV absorber (UV absorber below) 1.5 parts by mass Hardness improver (L-1 below) 6.5 parts by mass Hardener (M-1 below) 4.0 parts by mass Methylene chloride (first) Solvent) 609 parts by mass Methanol (second solvent) 91 parts by mass ―――――――――――――――――――――――――――――――――――――

Hardness improvers L-0 to L-4

Hardness improvers M-0 to M-3

  Next, these dopes were defoamed by irradiating weak ultrasonic waves. The degassed dope was passed through a sintered metal filter having a minimum nominal pore diameter of 5 μm while being pressurized to 1.5 MPa, and then passed through a sintered metal filter of 2.5 μm. The primary pressures were 1.5 MPa and 1.2 MPa, respectively, and the secondary pressures were 1.0 MPa and 0.8 MPa, respectively. The temperature of the dope after filtration was adjusted to 35 ° C. and stored in a stainless steel stock tank. The stock tank had an anchor blade on the central axis and was constantly stirred at a peripheral speed of 0.3 m / sec.

[Example 1]
(Casting)
In an environment in which the wavelength band of 200 to 450 nm is shielded (specifically, inside a room where only a fluorescent lamp provided with a UV cut filter is installed as illumination), an initiator-containing cellulose ester solution is discharged from a tip-joining die. The film was cast so as to have a film forming width of 2000 mm and the thickness described in Table 3 below, and formed on a drum support at 5 ° C. Then, 40 degreeC dehumidification air was applied on the drum, and the film was peeled off from the drum support body.
Then, 120 degreeC drying air was applied, the film was dried completely, 4000 m was wound up in roll shape, and the roll-shaped film was obtained. The film had a thickness of 40 μm.

<Shading>
In an environment where UV light in the wavelength band of 200 to 450 nm is shielded, the roll film is coated with a black light-shielding package (carbon black is kneaded with a transmittance of 0.01% or less for UV light in the wavelength band of 200 to 450 nm). A light-shielding roll film of Example 1 was produced.

<Manufacture of hard coat film>
(Preparation of hard coat layer coating solution (HC-1))
Each component was prepared with the composition shown below, and filtered through a polypropylene filter having a pore size of 30 μm to prepare a hard coat layer coating solution HC-1.

―――――――――――――――――――――――――――――――――――
Composition of coating liquid HC-1 for hard coat layer ―――――――――――――――――――――――――――――――――――
KAYARAD DPHA
(Nippon Kayaku: dipentaerythritol hexaacrylate) 100 parts by mass Toluene (solvent) 467 parts by mass cyclohexanone (solvent) 117 parts by mass Irgacure 184 (alkylphenone photopolymerization initiator; manufactured by BASF)
3 parts by mass ――――――――――――――――――――――――――――――――――――

(Formation of hard coat layer)
In an environment in which UV light having a wavelength band of 200 to 450 nm is shielded, a hard coat layer coating solution (HC) is formed on the surface of the cellulose ester layer of the film obtained by unwinding the shielded roll-shaped film formed as described above. -1) was applied by a microgravure coating method under conditions of a conveyance speed of 30 m / min.
After dried for 150 seconds at 60 ° C., with a nitrogen purge (hereinafter oxygen concentration of 0.5%), using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co.), illuminance 400 mW / cm ^2, irradiation The coating layer was cured by irradiating an ultraviolet ray having a quantity of 150 mJ / cm ² to form a hard coat layer having a thickness of 5 μm.
The obtained hard coat film was used as the hard coat film of Example 1.

[Examples 2 to 10 and Comparative Examples 1 to 4]
As described in Table 3 below, the light-shielded roll-shaped films and hard of Examples 2 to 10 and Comparative Examples 1 to 4 were the same as Example 1 except that the composition of the initiator-containing cellulose ester solution was changed. A coated film was produced. However, in Example 8, when the hard coat layer was formed, heat treatment was also performed at 140 ° C. for 10 minutes after the ultraviolet irradiation.
In Table 3 below, IRGACURE 819 is an acyl phosphine oxide photopolymerization initiator (BASF), IRGACURE OXE01 and IRGACURE OXE02 are oxime ester photopolymerization initiators (both BASF), Lunar 6 Is a photopolymerization initiator manufactured by AKOMA, and VF-096 is an azoamide photopolymerization initiator (2,2′-Azobis [N- (2-propenyl) -2-methylpropionamide] manufactured by Wako Pure Chemical Industries, Ltd.] ).

[Example 11]
(Co-casting)
Cellulose ester for base material layer from tip-joining die in an environment where the wavelength band of 200 to 450 nm is shielded (specifically, inside a room where only a fluorescent lamp provided with a UV cut filter is installed as illumination) The solution and the initiator-containing cellulose ester solution are laminated in the order of the cellulose ester solution for the base material layer and the initiator-containing cellulose ester solution in this order from the support side with a film forming width of 2000 mm and the thickness described in Table 3 below. Co-cast, and a two-layer laminate was formed on a 5 ° C. drum support. Then, 40 degreeC dehumidification air was applied on the drum and the laminated body was peeled off from the drum support body.
Then, using a tenter type stretching apparatus with a clip, the laminate was transversely stretched 7% in a direction (TD direction) perpendicular to the film transport direction while applying dry air at 70 ° C.
Then, 120 degreeC drying wind was applied, the film after extending | stretching was completely dried, 4000 m was wound up in roll shape, and the cellulose-ester roll-shaped film was obtained.
In the cellulose ester film of Example 11, the thickness of the cellulose ester for the base material layer was 35 μm, and the thickness of the initiator-containing cellulose ester was 5 μm.

(Shading)
In an environment where UV light in the wavelength band of 200 to 450 nm is shielded, the roll film is coated with black light-shielding packaging having a transmittance of 0.1% or less for UV light in the wavelength band of 200 to 450 nm (kneaded with carbon black) A light-shielding roll film of Example 11 was produced by covering with a light-shielding material which is a black film.

(Formation of hard coat layer)
In accordance with the same method as in Example 1, a hard coat layer coating solution (HC-1) was applied and photocured to form a hard coat layer to obtain a hard coat film.

[Example 12]
In Example 11, the light-shielded roll film of Example 12 was manufactured except that the thickness of the cellulose ester for the base layer was 30 μm and the thickness of the initiator-containing cellulose ester was 10 μm. Further, a hard coat layer was formed in the same manner as in Example 11 to obtain a hard coat film.

[Evaluation]
<Pencil hardness after HC application>
For the hard coat layers of the hard coat films of each Example and Comparative Example, the pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the hard coat film of each Example and Comparative Example for 2 hours at a temperature of 25 ° C. and a relative humidity of 60%, 500 g of HB, H, 2H and 3H test pencils specified in JIS S 6006 were used. The load was evaluated by the following judgment.
No evaluation for n = 5-one wound: OK
Two or more scratches in the evaluation of n = 5: NG
Among pencils having hardness that is OK, the hardness symbol of the hardest pencil was defined as pencil hardness.
In addition, the test direction (scratching direction) of the pencil was made parallel to the transport direction (longitudinal direction) at the time of forming a light-shielded roll-shaped film.
The obtained results are shown in Table 3 below.

<Cutability>
About the cutting property of the hard coat film of each Example and a comparative example, it evaluated on the following references | standards using the razor blade (Feather safety razor Co., Ltd. blue box single blade).
A: Can be cut without tearing straight. Powder does not come out.
B: Cannot be cut without tearing or powder comes out.
The obtained results are shown in Table 3 below.

From Table 3 above, it can be seen that the light-shielded roll-shaped film of the present invention can have a high surface hardness when the hard coat layer is laminated, and has good cutting properties after winding after the hard coat layer is provided. It was.
On the other hand, from Comparative Example 1, it was found that the film containing no polymerization initiator had a low surface hardness when the hard coat layer was laminated. From Comparative Example 2, it was found that the film having a polymerization initiator content lower than the lower limit of the present invention had a low surface hardness when the hard coat layer was laminated. From Comparative Example 3, it was found that a film in which the content of the polymerization initiator exceeds the upper limit of the present invention has poor cutting properties when the hard coat layer is laminated. From the comparison between Comparative Example 4 and Example 10, the film containing no polymerization initiator has a surface hardness as compared with Example 10 in which the hardness improver was added when the hard coat layer was laminated even though the hardness improver was added. I found it low.

[Examples 101 to 112]
<Preparation of polarizing plate>
(Saponification treatment of polarizing plate protective film)
Each hard coat film obtained in Examples 1 to 12 was immersed in a 2.3 mol / L sodium hydroxide aqueous solution at 55 ° C. for 3 minutes. It wash | cleaned in the room temperature water-washing bath, and neutralized using 0.05 mol / L sulfuric acid at 30 degreeC. Again, it was washed in a water bath at room temperature and further dried with hot air at 100 ° C. In this way, the surface of the hard coat film was saponified.

(Preparation of polarizing plate)
A polarizer was prepared by adsorbing iodine to a stretched polyvinyl alcohol film.
The saponified hard coat film was attached to one side of the polarizer using a polyvinyl alcohol-based adhesive. The same saponification treatment was applied to a commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Film Co., Ltd.), using a polyvinyl alcohol adhesive, opposite to the side where each hard coat film prepared above was attached. A cellulose triacetate film after saponification treatment was attached to the surface of the polarizer on the side.
At this time, the transmission axis of the polarizer and the slow axis of the obtained hard coat film were arranged in parallel. Further, the transmission axis of the polarizer and the slow axis of the commercially available cellulose triacetate film were arranged so as to be orthogonal to each other.
In this manner, polarizing plates of Examples 101 to 112 were produced.

<Production of liquid crystal display device>
The polarizing plate on the viewing side of a commercially available liquid crystal television (Sony Co., Ltd. BRAVIA J5000) is peeled off, and each polarizing plate produced in the above examples is used as the polarizing plate of the present invention. A liquid crystal display device was obtained by sticking one sheet at a time to the viewer side via an adhesive so that the cell side would be the opposite side.
Thus, the liquid crystal display device of Examples 101-112 was produced.
The display performance of the liquid crystal display devices of Examples 101 to 112 was good.

DESCRIPTION OF SYMBOLS 10 Casting apparatus 12 Support body 14 Casting die 16 1st solution 18 2nd solution 20 Discharge port 22 Laminated body (casting film)
22a Casting film derived from polymerizable compound-containing composition 22b Casting film derived from initiator-containing composition 24 Supply port 26 Supply port 28 First flow path 30 Second flow path 50 Polymer film 60 Film production facility 62 Drying section 64 Wet film 68 Roller 70 Tenter 72 Clip 74 Air duct 76 Cutting device 78 Roller 80 Drying chamber 82 Dry film 84 Curing device 86 Winding unit 88 Core

Claims (24)

A film comprising one layer or two or more layers and having a cellulose ester layer containing at least 10 to 20% by mass of a photopolymerization initiator based on the cellulose ester and the cellulose ester at the air interface was wound into a roll. A roll film;
A light-shielded roll-shaped film having a light-shielding material that covers the roll-shaped film and has a UV light transmittance of 0.1% or less in a wavelength band of 200 to 450 nm. The shielding light material, a light-shielding packaging having a light-shielding wrap or metal thin film layer of black, rolled films shielding according to claim 1. It consists of two or more layers, and further includes a base material layer,
Containing 1 wt% or more of the UV absorber with respect Lupo Rimmer included in the base layer, rolled films shielding according to claim 1 or 2. Lupo Rimmer included in the base layer is a cellulose ester, a roll film is shielded according to claim 3.   A film consisting of one layer or two or more layers and having a cellulose ester layer containing at least 10 to 20% by mass of a thermal polymerization initiator based on the cellulose ester and the cellulose ester at the air interface was wound into a roll. And a roll film containing a thermal polymerization initiator. It consists of two or more layers, and further includes a base material layer,
Containing 0.5 wt% or more of the UV absorber with respect to contained Lupo Rimmer to the substrate layer, a roll of film containing a thermal polymerization initiator according to claim 5. Lupo Rimmer included in the base layer is a cellulose ester, a roll film comprising a thermal polymerization initiator according to claim 6. A step (1) of forming a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 10 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester and the cellulose ester at an air interface; ,
A step (2) of winding the film into a roll to form a roll film;
UV light transmittance at a wavelength band of 200~450nm comprising the step (3) for shielding the rolled film by using an optical material shielding 0.1% or less, shading process for the preparation of the rolled film. Casting or co-casting a composition for a base material layer containing a polymer and a composition containing 10 to 20% by mass of a photopolymerization initiator based on the cellulose ester and the cellulose ester on a support. A step (1-1) of forming a film having at least the cellulose ester layer at the air interface,
Wherein a film having at least an air interface cellulose ester layer and the support or we exfoliation to step including (1-2), the light-shielding process for the preparation of the rolled film according to claim 8. A step (1S) of forming a film comprising one layer or two or more layers and having a cellulose ester layer at least at the air interface including a cellulose ester and 10 to 20% by mass of a thermal polymerization initiator based on the cellulose ester; ,
The manufacturing method of the roll-shaped film containing a thermal-polymerization initiator including the process (2) which winds up the said film in roll shape, and forms a roll-shaped film. Casting or co-casting a composition for a base layer containing a polymer and a composition containing 10 to 20% by mass of a thermal polymerization initiator based on the cellulose ester and the cellulose ester on a support. A step (1S-1) of forming a film having at least the cellulose ester layer at the air interface,
Comprising said cellulose ester layer at least step of the film with the air interface to release the support or al peeling (1S-2), the production method of the rolled film comprising a thermal polymerization initiator according to claim 10. The composition for hard-coat layer formation containing a polymerizable monomer and a photoinitiator on the said cellulose-ester layer of the film which unwound the light-shielded roll-shaped film as described in any one of Claims 1-4. Applying (4A),
The manufacturing method of a hard-coat film including the process (5) of photocuring the said composition for hard-coat layer formation. A step (1) of forming a film comprising one layer or two or more layers and having a cellulose ester layer containing at least 10 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester and the cellulose ester at an air interface; ,
(4B) applying a hard coat layer forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer;
Photocuring the hard coat layer forming composition (5),
Hard coating in which the step (1) and the step (4B) are performed in an environment where UV light having a wavelength band of 200 to 450 nm is shielded from the start of the step (1) to the end of the step (4B). A method for producing a film. Hard coat layer formation containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the roll film containing the thermal polymerization initiator according to any one of claims 5 to 7. A step of applying a composition (4S),
Photocuring the hard coat layer forming composition (5);
The manufacturing method of a hard-coat film including the process (6) of thermosetting the said composition for hard-coat layer formation. A step (1S) of forming a film comprising one layer or two or more layers and having a cellulose ester layer at least at the air interface including a cellulose ester and 10 to 20% by mass of a thermal polymerization initiator based on the cellulose ester; ,
(4A) applying a hard coat layer-forming composition containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer;
Photocuring the hard coat layer forming composition (5);
The manufacturing method of a hard-coat film including the process (6) of thermosetting the said composition for hard-coat layer formation.   The manufacturing method of the hard coat film as described in any one of Claims 12-15 whose process (5) of photocuring the said composition for hard-coat layer formation is a process of irradiating an ultraviolet-ray.   The manufacturing method of the hard-coat film as described in any one of Claims 12-16 including the process of drying the said composition for hard-coat layer formation after the said hardening process.   The hard coat film manufactured with the manufacturing method of the hard coat film as described in any one of Claims 12-17. The composition for hard-coat layer formation containing a polymerizable monomer and a photoinitiator on the said cellulose-ester layer of the film which unwound the light-shielded roll-shaped film as described in any one of Claims 1-4. After is applied
A hard coat film formed by photocuring. Cellulose ester comprising one layer or two or more layers in an environment where UV light having a wavelength band of 200 to 450 nm is shielded, and containing 10 to 20% by mass of a photopolymerization initiator with respect to the cellulose ester. After the composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator is applied onto the cellulose ester layer of the film having at least an air interface,
A hard coat film formed by photocuring. Hard coat layer formation containing a polymerizable monomer and a photopolymerization initiator on the cellulose ester layer of the film obtained by unwinding the roll film containing the thermal polymerization initiator according to any one of claims 5 to 7. After the composition is applied,
A hard coat film formed by photocuring and heat curing. On the cellulose ester layer of the film, which is composed of one layer or two or more layers and has a cellulose ester layer containing at least the cellulose ester and a thermal polymerization initiator of 10 to 20% by mass with respect to the cellulose ester at the air interface After the composition for forming a hard coat layer containing a polymerizable monomer and a photopolymerization initiator is applied,
A hard coat film formed by photocuring and heat curing. A polarizer,
The polarizing plate which has a hard coat film as described in any one of Claims 18-22. A liquid crystal cell;
A liquid crystal display device comprising the hard coat film according to any one of claims 18 to 22 or the polarizing plate according to claim 23.

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