JP3269064B2 - Relief material manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a relief material having a relief image formed of a concavo-convex pattern or a relief pattern on the surface. More specifically, the present invention manufactures a relief material having a relief image by "light molding technology" in which a photocurable material is selectively irradiated with light and the irradiated portion is cured to form a desired molded body. On how to do it.

[0002]

2. Description of the Related Art A relief material having a relief image formed of a concavo-convex pattern or a relief pattern on its surface has been used for a relief printing plate, an embossing roll, and the like. It is widely used to manufacture. For example, a photo-curable material made of a solid or liquid photosensitive resin, or a photo-curable material containing a photo-polymerizable monomer or oligomer or a reactive prepolymer, if necessary, is irradiated with light. Relief materials have been manufactured by curing portions and then removing unirradiated portions of the photocurable material to form a relief image.

[0003]

However, in the production of the above-mentioned conventional relief material, in order to remove the non-irradiated portion of the photocurable material, the unirradiated portion is heated and melted and absorbed by absorbent paper. There is a problem that a complicated operation such as removal, removal of the unirradiated portion by dissolution or etching removal using a developing solution or stripping solution containing an acid, an alkali or an organic solvent is required. In addition, there is also a problem that an operation for performing such removal often has an adverse effect on the human body and the global environment.

An object of the present invention is to solve the problems of the prior art as described above, and to make it possible to easily and safely manufacture a relief material from a photocurable material by using a photoforming technique. Aim.

[0005]

Means for Solving the Problems The present inventors have found that a photopolymerizable monomer or oligomer in the 3-dimensional network structure of Ruge Le such from isotactic polymethyl methacrylate and syndiotactic polymethyl methacrylate When light is selectively irradiated according to the relief image to be formed on the gel structure incorporating the gel, the irradiated part of the gel structure is cured and the unirradiated part is dented, and as a result, the irradiated part becomes a convex part The present inventors have discovered a phenomenon in which an unirradiated portion becomes a concave portion, and have found that the above-mentioned object can be achieved by utilizing this phenomenon, thereby completing the present invention.

That is, the present invention is to form a gel structure from a photocurable composition comprising an isotactic polymethacrylate, a syndiotactic polymethacrylate and a photopolymerizable monomer or oligomer,
Hekomase a and unirradiated portion is cured and the irradiated portion by irradiating light to the part of the gel structure, forming thereby a relief image consisting of convex irradiated portion and the concave unirradiated portion Then, there is provided a method for producing a relief material, which comprises curing an unirradiated portion of the gel structure.

Hereinafter, the method for producing a relief material of the present invention will be described in detail with reference to FIG.

[0008] Lerry according to the present invention utilizing photoforming technology
Production process 1 of the full material is first prepared isotactic polymethacrylate, photocurable gel structure comprising syndiotactic polymethacrylic acid esters and a photopolymerizable monomer or oligomer. Generally, as shown in FIG. 1A, a gel structure 1 is formed in a layer on a substrate 2.

As a method for forming such a gel structure 1, first, an isotactic polymethacrylate, a syndiotactic polymethacrylate, and a sol or gel, which can be in a sol or gel state by temperature control, can be used. A photocurable composition comprising a polymerizable monomer or oligomer is prepared, and the photocurable composition is heated to form a uniform photocurable sol, and the sol is applied to the substrate 2 by a doctor blade or the like and cooled. Thus, the gel structure 1 can be formed by gelation. Alternatively, the gel photocurable composition may be processed into a sheet by extruding from a die having a slit-shaped extrusion port.

The photocurable gel structure 1 according to the present invention comprises:
The photopolymerizable monomer or oligomer is incorporated and held in the gel structure having the three-dimensional network structure. Further, the three-dimensional network structure is constituted of a mixture of isotactic polymethacrylate ester and a syndiotactic polymethacrylate ester can be formed around room temperature Dege Le.

Here, as the isotactic polymethacrylate, the proportion of isotactic triads (three consecutive monomer units) in the polymer is at least 50%, preferably at least 60%, of all monomer units. As the syndiotactic polymethacrylate, one having a proportion of syndiotactic triads of 50% or more, preferably 60% or more, of all monomer units is used.

Further, as these isotactic polymethacrylates or syndiotactic polymethacrylates, those having a weight average molecular weight of 1,000 or more, more preferably 10,000 or more are used. Further, as these esters, those having a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms, more preferably a lower linear alkyl group, and particularly preferably a methyl group are used.

The weight ratio of the isotactic polymethacrylate to the syndiotactic polymethacrylate varies depending on the degree of polymerization, tacticity, etc., but the handleability of the gel structure 1 (gel strength and gel melting point)
In general, the ratio is preferably 1:10 to 10: 1 from the viewpoint of the sensitivity of forming a relief image and the sensitivity of forming a relief image (sensitivity of forming unevenness difference).

These isotactic polymethacrylates or syndiotactic polymethacrylates are used to modify the gel structure obtained therefrom in order to modify other vinyl monomers such as styrene and acrylate. Units may be included.

[0015] Isotactic polymethyl methacrylate es in the photo-curable composition for forming the gel structure 1
The content of ether, from the viewpoint of handleability and relief images forming sensitivity of the gel structure, at least 1 wt% is preferred,
2-20% by weight is more preferred. Further, the content of the syndiotactic polymethacrylate in the photocurable composition is preferably at least 1% by weight, and more preferably 3 to 30% by weight.

The photopolymerizable monomer or oligomer used in the present invention is used as a photocurable component in a photocurable gel structure formed from a photocurable composition,
At a temperature higher than the melting point of the gel, it also functions as a solvent for dissolving the isotactic polymethacrylate and the syndiotactic polymethacrylate forming the gel structure to form a uniform sol. Is what it is. Such a photopolymerizable monomer can be appropriately selected and used from various photopolymerizable monomers capable of photopolymerization. For example, acrylic acid, methyl acrylate, acrylates such as trimethylolpropane triacrylate, methacrylic acid, methyl methacrylate, methacrylates such as trimethylolpropane trimethacrylate, propylene oxide, epoxy compounds such as glycidyl ether, ethyl vinyl ether And the like, vinyl compounds such as styrene, cyclic ethers such as cyclooxabutane, and vinyl esters such as vinyl acetate. These may be used alone or in combination of two or more. Further, oligomers formed from these monomers and other oligomers such as butadiene oligomers can also be used in the present invention.

The content of the photopolymerizable monomer or oligomer in the photocurable composition is generally 10% by weight or more, preferably 30% by weight, in consideration of the sensitivity of forming a relief image.
~ 95% by weight.

The photocurable composition can further contain a photopolymerization initiator, and can be appropriately selected from known photopolymerization initiators. Examples of such a photopolymerization initiator include benzoin alkyl ethers such as benzoin ethyl ether, benzoin butyl ether and benzoin propyl ether; acetophenones such as 2,2-diethoxyacetophen and 4'-phenoxy-2,2-dichloroacetophenone. , 2-hydroxy-2-
Methylpropyl phenone, 4'-isopropyl-2-hydroxy-2 - propyl phenones such methylpropyl phenone, 4'-dodecyl-2-hydroxy-2-methylpropyl phenone, benzyl phenylalkyl ketals such as benzyl methyl ketal, Acylphosphines such as 2,4,6-trimethylbenzylphenylphosphinoxide, anthraquinones such as 2-ethylanthraquinone and 2-chloroanthraquinone, and other thioxanes, diazonium salts, diallyliodonium salts, and triarylsulfonium salts; Triarylselenonium salts, silanol / aluminum complex, 1
-Hydroxydicyclohexyl phenyl ketone, etc., and these can be used as a mixture of one or more kinds.

The amount of the photopolymerization initiator varies depending on the type of the photopolymerization initiator, but is generally from 0.01 to 10 in the photocurable composition.
It is preferable to set the weight%.

In the present invention, if necessary, a filler such as barium sulfate, clay, aluminum hydroxide or calcium carbonate, or a liquid such as a photopolymerizable monomer from a gel structure may be added to the photocurable composition. Various general additives such as a gel improving agent such as N-acylamino acid amine salts, a coloring agent, a releasing agent, and a leveling agent can be added to effectively prevent bleeding.

The substrate 2 on which the gel structure 1 is formed is not particularly limited as long as it can support the gel structure, and a glass plate or a polymethacrylate plate can be used.

[0022] Step 2 Next, a relief to be formed consists gel structure 1 from a mixture of isotactic polymethacrylate ester and a syndiotactic polymethacrylate ester can be formed around room Dege Le Light is selectively irradiated according to an image. To this end, as shown in FIG. 1B, a photomask 4 is disposed on the gel structure 1 via a light-transmitting film 3 and light is irradiated from above on the gel structure as shown by arrows in the figure. I just need. Thereby, as shown in FIG. 1 (c), the irradiated portion B of the gel structure 1 is hardened and the unirradiated portion A is dented. As a result, the concave unirradiated portion A and the convex irradiated portion B Is formed.

The light transmissive film 3 is provided for preventing the photomask 4 and the gel structure 1 from coming into direct contact with each other as necessary. Therefore, when the photomask 4 and the gel structure 1 may be brought into contact with each other or when a predetermined interval can be maintained, the step can be omitted. As such a light-transmitting film 3, it is preferable to use a film that does not integrate with the gel structure even when the gel structure 1 is cured, and that transmits at least irradiation light. Specifically, although it differs depending on components used in the gel structure, for example, a polyethylene terephthalate film or the like can be used. The photomask 4 is formed from a material capable of blocking irradiation light by a conventional method.

The light used to cure the gel structure 1 depends on the type of polymerization initiator and photopolymerizable monomer used, but it is preferable to use light having a wavelength of 150 to 600 nm. Examples of a device that generates light having such a wavelength include a carbon arc lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a chemical lamp, a xenon lamp, and a semiconductor laser.

The gel light may be scanned on the gel structure 1 without using a photomask or the like.

Step 3 Next, the non-irradiated portion A is cured, and a relief image including the concave portion of the non-irradiated portion A and the convex portion of the irradiated portion B is fixed. To this end, as shown in FIG. 1D, the light-transmitting film 3 and the photomask 4 may be removed, and the whole may be irradiated with light as shown by the arrow in the figure. As a result, FIG.
The relief material 10 having a relief image as shown in FIG.

When the unirradiated portion A is cured, it may be heated and thermally polymerized and cured without irradiating light.

The thus produced relief material can be used for applications such as relief printing plates, embossing rolls and decorative reliefs.

[0029]

The gel structure used in the method for producing a relief material of the present invention comprises a three-dimensional network gel structure comprising isotactic polymethacrylate and syndiotactic polymethacrylate in a photopolymerizable monomer or photopolymer. Holds polymerizable oligomer. When such a photocurable gel structure is selectively irradiated with light in accordance with a relief image to be formed, an irradiated portion of the gel structure is cured. At this time, a part of the photopolymerizable monomer or oligomer existing in the unirradiated portion of the gel structure penetrates into the irradiated portion and is cured there. Therefore, the irradiated portion relatively becomes a convex portion and the non-irradiated portion becomes a concave portion. Then, a relief image is formed from the convex portions and the concave portions. Thereafter, the unirradiated portion is cured by light irradiation or thermal polymerization to fix the relief image. Therefore, according to the present invention, the unirradiated part of the photocurable gel structure is removed by heating and melting and absorbing the absorbent with absorbent paper, or a developer or stripper containing an acid, alkali or organic solvent. An operation of dissolving or removing by etching or the like becomes unnecessary.

[0030]

The present invention will be described in more detail with reference to the following examples.

Example a) Synthesis of isotactic poly (methyl methacrylate) First, a starting material, methyl methacrylate, toluene and a diethyl ether solution of t-butylmagnesium bromide were appropriately passed through a molecular sieve 4A in a dry nitrogen atmosphere. Purified as shown below below.

Methyl methacrylate is obtained by heating and refluxing a commercially available reagent in the presence of calcium hydride for 2 hours, followed by simple distillation, further treatment in the presence of lithium aluminum hydride, and then vacuum distillation to obtain a molecular sieve. Purification was performed by allowing to stand at room temperature for 3 days in the presence of 4A and drying.

With respect to toluene, a commercially available reagent is washed with concentrated sulfuric acid, washed once with a saturated aqueous solution of sodium hydrogencarbonate, washed three times with water, dried over magnesium sulfate for one day, and filtered off magnesium sulfate. Then, the mixture is refluxed for 2 hours in the presence of calcium hydride, subsequently subjected to simple distillation, further treated with metallic sodium, then again simple distilled, and left to stand at room temperature for 3 days in the presence of molecular sieves 4A and dried. And purified.

The diethyl ether solution of t-butylmagnesium bromide was synthesized and purified according to a general Grignard reagent synthesis method. The concentration of t-butylmagnesium bromide in diethyl ether was determined by acid-base titration of the amount of magnesium.
As a result, the concentration of t-butylmagnesium bromide (diethyl ether solution) was 0.24 mol / L.

Using the raw materials thus purified, isotactic poly (methyl methacrylate) was synthesized as shown below.

That is, under a dry nitrogen atmosphere through Molecular Sieves 4A, 20 ml of methyl methacrylate and toluene were each injected into a 100 ml glass ampule with a syringe, and the mixture was cooled in a cooling oven at -45 ° C. While stirring the mixture, 0.8 ml of a t-butylmagnesium bromide solution in diethyl ether was injected into the mixture with a syringe to start anionic polymerization.
Maintained at 45 ° C. Thereafter, 2 ml of 1N hydrochloric acid was added to the reaction solution to stop the polymerization reaction.

Remove the reaction product from the ampoule and
After immersion in 1 liter of methanol for 2 days, the polymer was pulverized, filtered with a glass filter, washed with methanol,
By vacuum drying at 50 ° C. for 4 hours, isotactic polymethyl methacrylate was obtained in a yield of about 28%. The triad isotacticity of the obtained isotactic poly (methyl methacrylate) determined by proton nuclear magnetic resonance spectrum was 85%. The weight average molecular weight measured by gel permeation chromatography was 41,000 in terms of polystyrene.

B) Synthesis of syndiotactic polymethyl methacrylate A 100 ml glass ampoule was charged with 10 ml of commercially available methyl methacrylate, 50 ml of toluene and 0.03 g of benzoyl peroxide as a radical polymerization initiator. After 1 minute of nitrogen bubbling, 80 ° C
To start the radical polymerization, and the temperature was maintained for 2 days.

Thereafter, the reaction mixture was cooled to 1000 m
The resulting polymer was precipitated by dropwise addition to 1 liter of methanol. The precipitated polymer was collected by filtration with a glass filter, washed with methanol, and dried in vacuo at 50 ° C. for 4 hours to obtain a syndiotactic poly (methyl methacrylate) in a yield of about 97%. The triad syndiotacticity of the obtained syndiotactic poly (methyl methacrylate) determined by proton nuclear magnetic resonance spectrum was 60%. The weight average molecular weight measured by gel permeation chromatography was 9 in terms of polystyrene.
8000.

C) Preparation of photocurable composition 3.3 parts by weight of isotactic polymethyl methacrylate obtained by the above-mentioned means, and 6.7 of syndiotactic polymethyl methacrylate obtained by the above-mentioned means. Parts by weight, methyl methacrylate 67 parts by weight, trimethylolpropane triacrylate 23 parts by weight and 2-
A mixture of 0.2 parts by weight of hydroxy-2-methylpropiophenone is heated to 70 ° C. to dissolve isotactic polymethyl methacrylate and syndiotactic polymethyl methacrylate, thereby obtaining a sol-form photocurable composition. Was cooled to room temperature to obtain a gel-like photocurable composition.

D) Production of Relief Material The gel-like photocurable composition obtained by the above-mentioned means is extruded from a die having a slit of 3 mm width onto a 3 m-thick transparent substrate made of polymethyl methacrylate. Thus, a sheet-like photocurable gel structure 1 was formed as shown in FIG. Further, on this gel structure 1, 20
A transparent polyethylene terephthalate film 3 having a thickness of 0 μm, a photomask 4 made of stainless steel having a thickness of 200 μm, and a glass plate 5 having a thickness of 1 mm were sequentially placed thereon.

Next, the irradiated portion of the gel structure was cured by irradiating light having a main wavelength of 365 nm for 10 minutes from above the glass plate 5 by 10 cm using a chemical lamp (UVA 40W, manufactured by Philips). As a result, a relief image in which the irradiated portion was relatively raised by about 1 mm from the non-irradiated portion could be formed.

The glass plate 5, the photomask 4, and the transparent polyethylene terephthalate film 3 on the gel structure 1 on which the relief image is formed are removed, and the whole gel structure is irradiated with light again under the same conditions. Cured. As a result, a relief material having a relief image could be manufactured.

[0044]

According to the present invention, when a relief material having a relief image is produced from a photo-curable material using a photo-forming technique, the unirradiated portion is heated and melted and absorbed by an absorbent paper to be removed. Without removing or etching away the unirradiated portion using a developer or stripper containing an acid, alkali or organic solvent, etc. A relief image can be formed simply and safely by irradiating light to a portion to be a convex portion and then curing an unirradiated portion.

[Brief description of the drawings]

FIG. 1 is a process explanatory view of a method for producing a relief material of the present invention.

FIG. 2 is an explanatory diagram of a method for manufacturing a relief material according to an example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gel structure 2 Substrate 3 Light transmissive film 4 Photomask 5 Glass plate

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenichi Hamada 2-28, Kurashiki-cho, Nakajo-cho, Kitakanbara-gun, Niigata Inside Kuraray Co., Ltd. (72) Inventor Yoshifumi Murata 2-28, Kurashiki-cho, Nakajo-cho, Kitakanbara-gun, Niigata (72) Inventor Hiroshi Samukawa 3-3-11 Mohridai, Atsugi-shi, Kanagawa Prefecture (72) Inventor Yoji Hagiwara 4-1, 5-203 Miyanosato, Atsugi-shi, Kanagawa (56) References JP-A-4-278333 (JP, A) JP-A-4-225009 (JP, A) JP-A-4-293909 (JP, A) JP-A-52-116301 (JP, A) JP-A-52-102359 (JP, A) A) JP-A-4-6562 (JP, A) JP-A-5-32743 (JP, A) JP-A-5-93003 (JP, A) JP-A-4-3162 (JP, A) JP-A-49 JP-A-37879 (JP, A) JP-A-52-4834 (JP, A) JP-A-62-2541 42 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03F 7/038 G03F 7/00 502 G03F 7/027 511 G03F 7/36

Claims (3)

(57) [Claims] 1. A gel structure is formed from a photocurable composition comprising an isotactic polymethacrylate, a syndiotactic polymethacrylate, and a photopolymerizable monomer or oligomer .
Hekomase a and unirradiated portion is cured and the irradiated portion by irradiating light to the part, thereby forming a relief image comprising a convex of the irradiated portion and the concave unirradiated portion, and then the gel structure A method for producing a relief material, comprising curing an unirradiated portion of a body. 2. The method according to claim 1, wherein the non-irradiated portion of the gel structure is cured by irradiating light after forming the relief image. 3. The method for producing a relief material according to claim 1, wherein the photocurable composition contains at least 1% by weight of each of an isotactic polymethacrylate and a syndiotactic polymethacrylate. .