JP3397231B2 - Photosensitive element - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to photosensitive elements.

[0002]

2. Description of the Related Art Conventionally, in the precision processing industry, for example, in the manufacture of printed wiring boards, etc., a protective film, a photosensitive resin layer, and a support are used to form resists such as plating and etching and to form permanent masks such as electroless plating masks and solder masks. It is known to use photosensitive elements consisting of three layers of body film. Since the pattern forming method by the photographic method using the photosensitive element has the advantage that the thickness is uniform and the fine line can be formed with high accuracy as compared with the screen printing method, the lead frame for mounting the IC chip, the color TV, V
The application thereof is being widely studied for forming parts for various industrial electronic devices such as TR and audio parts, and for forming parts for consumer electronic devices. Along with this, the thickness of the photosensitive resin layer of the conventional photosensitive element is 25 to 50 μm.
However, a thick film having a thickness of 100 to 250 μm is required.

In the photosensitive element, a solution of a photosensitive resin composition is uniformly applied on a support film, the solvent is evaporated by drying to form a photosensitive resin layer, and then the photosensitive resin layer is formed. attaching a protective film, it is produced by winding into a roll. When the photosensitive element is used, the photosensitive resin layer is heated and pressure-bonded to the substrate surface while the protective film is peeled off. Then, a negative mask is placed on the support film, exposed and developed to form a photosensitive resin pattern on the substrate.

From these facts, the support film used for the photosensitive element should be sufficiently resistant to the heat at the time of coating and drying the solution of the photosensitive resin composition at the time of forming the photosensitive resin layer.
The one with excellent heat resistance, and the little light dispersion during exposure,
Select a plastic film with good UV transparency,
It is used. On the other hand, the protective film is used for the purpose of preventing damage from the outside of the photosensitive resin layer and adhesion of foreign matter, and when using the photosensitive element, the protective film is peeled off and bonded to the substrate, When the protective film is peeled off, it is troublesome that the photosensitive resin layer is also peeled off from the support film together. Therefore, the adhesive force A between the protective film and the photosensitive resin layer is less than the adhesive force B between the support film and the photosensitive resin layer. A plastic film is selected. For these reasons, a polyethylene terephthalate film is generally used as the support film and a polyethylene film is used as the protective film. However, as the thickness of the photosensitive resin layer increases, problems such as wrinkles, folds, peeling, and scratches on the photosensitive element occur over time. There is a problem that the edge fusion that oozes out is remarkable.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a photosensitive element which is excellent in storage stability and does not cause problems such as wrinkles, folds, peeling and edge fusion during storage. Further, the present invention provides a photosensitive element which exhibits the above-mentioned effects and can be suitably used in the fields in which an adherend having a large unevenness on the surface and a thick film pattern are required.

[0006]

The present invention provides a photosensitive element having a plastic film A, a photosensitive resin layer and a plastic film B, in this order, for forming a photosensitive resin pattern on a substrate. The film A has an elastic modulus of 50 kg / mm ² or more and a melting point of 130 ° C. or more, the plastic film A is a film that is removed when the substrates are bonded together, and the plastic film B is a polyethylene terephthalate film or a polypropylene film, The present invention relates to a photosensitive element in which the thickness of the photosensitive resin layer is 160 to 300 μm. Further, the present invention provides a photosensitive element having a plastic film A, a photosensitive resin layer and a plastic film B in this order for forming a photosensitive resin pattern on a substrate, wherein the plastic film A has an elastic coefficient of 50 kg. / Mm ² or more and melting point 130
℃ or more, the plastic film A is a film that is removed during bonding substrate, concerning the thickness of the photosensitive resin layer is 160 ～300Myuemu photosensitive element <br/>. Further, the present invention, the photosensitive resin layer while peeling off the plastic film A related bonding method of a photosensitive element, characterized in that attached to a substrate over the photosensitive element. Further, the present invention is a photosensitive element having a protective film, a photosensitive resin layer and a support film in this order, wherein the protective film is a plastic film having an elastic modulus of 50 kg / mm ² or more and a melting point of 130 ° C. or more. , The thickness of the photosensitive resin layer is
About the photosensitive element is 160 ~300μm.
Further, the present invention relates to a bonding method of a photosensitive element, wherein the bonding the photosensitive resin layer while peeling off the protective film of the photosensitive element on a substrate.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Plastic used in the present invention
Film A (hereinafter referred to as "protective film" in some cases)
U) is a plastic film having an elastic modulus of 50 kg / mm ² or more and a melting point of 130 ° C. or more. The elastic modulus is preferably 70 to 1000 kg / mm ² ,
It is more preferably 110 to 800 kg / mm ² . The melting point is preferably 140 to 400 ° C.,
It is more preferably 160 to 350 ° C. Using a wrinkle or a fold during storage of the photosensitive element the elastic modulus 50 kg / mm ² or less than a melting point of less than 130 ° C. Film as a protective film, peeling, problems occur such as edge fuge ® down. The elastic modulus is ASTM-D8.
82, and the melting point can be measured with a differential scanning calorimeter (DSC). The plastic film whose elastic modulus and melting point are within the range of the present invention can be selected and used from commercially available polypropylene film, polyethylene terephthalate film and the like.

The photosensitive resin layer in the present invention has its properties (solubility in solvent etc., tackiness, viscosity, fluidity, elastic modulus, elongation, viscoelasticity such as strength, surface tension, etc.) when exposed to light. Are known, and known ones can be used without particular limitation, for example,
It can be formed using a negative photosensitive resin composition, a positive photosensitive resin composition, or the like. As the positive type photosensitive resin composition, known ones can be used without particular limitation, and examples thereof include soluble group photogenerating type compositions using 1,2-naphthoquinonediazide compounds, o-nitrobenzyl compounds, and the like. Examples thereof include a photoacid generating / acid decomposing type composition using an onium salt and the like. The negative photosensitive resin composition is not particularly limited and known ones can be used. For example, (a) an ethylenically unsaturated compound, (b) a film-forming polymer and (c) a photopolymerization initiator are essential components. In addition, (d) dye or pigment, (e) other additives, (f) organic solvent and the like may be included as optional components.

Examples of the (a) ethylenically unsaturated compound include butyl acrylate, tetraethylene glycol diacrylate, γ-chloro-β-hydroxypropyl-β'-methacryloyloxyethyl-o-phthalate and tetrapropylene glycol diacrylate. Acrylate,
2,2-bis [(4-methacryloxypentaethoxy)
Acrylates such as phenyl] propane, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and methacrylates corresponding to these are included.

Examples of the film-formability-imparting polymer (b) include acrylic acid, methacrylic acid, an alkyl ester of acrylic acid having 1 to 22 carbon atoms, an alkyl ester of methacrylic acid having 1 to 22 carbon atoms, and 2-hydroxyethyl. acrylates DOO, 2-hydroxy sheet ethyl Rume Takurire <br/> DOO, 2-hydroxypropyl acrylated DOO, 2-hydroxypropyl methacrylate, glycidyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, acrylonitrile, N-
Methylol acrylamide, N- Mechiro Le methacrylamide, styrene, vinyl monomer and a vinyl copolymer obtained by copolymerizing these vinyl monomers copolymerizable with monomers such as vinyl toluene, polyesters, polyamides Acid etc. are mentioned. It is preferable that the film-forming property-imparting polymer (b) is a polymer having a carboxyl group, since it can be developed with an alkaline developer having excellent environmental properties.

Examples of the photopolymerization initiator (c) include benzophenone, 4,4'-diethylaminobenzophenone, 2-ethylthioxanthone, 1,7-bis (9-acridinyl) heptane, benzoin methyl ether and benzyldimethyl ketal. Is mentioned. Examples of the (d) dye or pigment include malachite green and phthalocyanine green. (E) Other additives include, for example, plasticizers such as diethylene glycol, adhesion improvers such as benzotriazole and tetrazole, silicone surfactants having a leveling effect and a defoaming effect, leuco crystal violet,
Color formers such as tribromomethylphenyl sulfone can be used. (F) Organic solvents include, for example, acetone, methyl ethyl ketone, toluene, ethyl acetate, butyl acetate, 2-
Butoxyethanol, 2-ethoxyethanol, 2-ethoxyethyl acetate tape DOO, methanol, N- methyl-2
-Pyrrolidone and the like can be mentioned.

Here, the blending amount of the component (a) is from the viewpoints of film forming property, low edge fusion property, photosensitivity, etc.
It is preferable that the total amount of the components (a) and (b) is 100 to 20 parts by weight based on 100 parts by weight. Also, (b)
From the viewpoints of photosensitivity, low edge fusion property, film forming property, etc., it is preferable that the amount of the components is 20 to 80 parts by weight based on 100 parts by weight of the total amount of the components (a) and (b). From the viewpoint of photosensitivity and the like, it is preferable that the compounding amount of the component (c) is 1 to 10 parts by weight based on 100 parts by weight of the total amount of the components (a) and (b). Also,
The blending amount of the component (d) is 0.1 to 1 with respect to 100 parts by weight of the total amount of the components (a) and (b) from the viewpoint of workability.
It is preferably 0 part by weight. Further, the amount of the component (e) blended is 0.1 to 20 with respect to 100 parts by weight of the total amount of the components (a) and (b) from the viewpoint of sufficiently exerting the effect.
It is preferable to use parts by weight. Further, the blending amount of the component (f) is preferably 50 to 300 parts by weight based on 100 parts by weight of the total amount of the components (a) and (b) from the viewpoints of coatability and productivity.

The amount of solvent (residual solvent amount) contained in the photosensitive resin layer is preferably 2% by weight or less from the viewpoint of suppressing the variation in quality. This residual solvent amount can be reduced to 0.1% by weight in the production of the photosensitive element.

The fluidity of the photosensitive resin layer is preferably 100 to 300 μm from the viewpoints of conformability to an adherend such as a substrate, low deformability and low edge fusion property.
More preferably, it is about 250 μm. Setting the fluidity within the above range can be performed by adjusting the types and blending amounts of the components (a) to (f). The fluidity here means that a photosensitive resin layer having a diameter of 20 mm and a thickness of 2 mm is used as a sample, the sample is placed on a flat substrate, and a static load of 5 kg in a cylindrical shape having a diameter of 50 mm is applied on the sample to deform it. to go after 10 seconds of the photosensitive resin layer thickness T ₁
(Μm) to be after 900 seconds Thickness _{T 2 (μm) T 1 -T} 2 at the time of the measurement of the (μm).

When the thickness of the photosensitive resin layer is 160 μm or more, the effect of the present invention is exhibited well, and the photosensitive element having such a photosensitive resin layer is used for an adherend having a large surface irregularity. It can be preferably used in fields requiring thick film patterns. The upper limit of this thickness is usually 300 μm.

Plastic film used in the present invention
B (hereinafter sometimes referred to as "support film") is
In the production of the photosensitive element described below, known materials can be used without particular limitation as long as they are resistant to damage by a solvent and heat and can finally support the photosensitive resin layer. Polyethylene terephthalate film is suitable as the material. The thickness of the support film is preferably 3 to 100 μm from the viewpoint of resolution, strength and handleability.

In the photosensitive element of the present invention, for example, a solution of a photosensitive resin composition (including a solvent such as an organic solvent) is applied on a support film and dried by heating to volatilize and remove the solvent, It can be obtained by forming a photosensitive resin layer and then laminating a protective film on the photosensitive resin layer. The photosensitive element can be wound into a roll. In the case of a roll-shaped product, it is preferable to wind the support film so that the support film is on the outer side, from the viewpoint of ease of handling thereafter.

The thickness of the photosensitive resin layer is 160 μm.
In the above case, since the bending rigidity of the photosensitive resin layer increases as the thickness of the photosensitive resin layer increases, the adhesive force A between the protective film and the photosensitive resin layer is Even if it is equal to or larger than the adhesive force B with the resin layer,
When the protective film is peeled off, the disadvantage of peeling between the photosensitive resin layer and the support film does not occur. Further, from the viewpoint of suppressing the deformation of the photosensitive resin layer, it is effective that the adhesive force A between the protective film and the photosensitive resin layer is as large as possible.

Since the adhesive force A and the adhesive force B may be equal, a plastic film having the same component or the same composition (material) as the main component can be used for both the protective film and the support film.

In the present invention, the photosensitive element using the polyethylene terephthalate film as both the protective film and the support film is hardly affected by thermal deformation, deformation of the photosensitive resin layer, etc. outstanding. In particular, a polyethylene terephthalate film has a uniform thickness, and since the slidability between the films is poor, it can be wound into a roll with low tension, so that edge fusion is less likely to occur, which is very preferable.

When the support film is a film having a smaller thickness than the protective film, the adhesion between the support film and the photosensitive resin layer can be further maintained, and the support film and the photosensitive resin layer are preferable. No peeling can be prevented.

The photosensitive element of the present invention is used for manufacturing printed wiring boards, forming lead frames for mounting IC chips,
It is suitable for etching, plating resist pattern formation, and various resin pattern formation when performing precision processing such as component formation for various industrial and consumer electronic devices such as formation of color television, VTR, and audio components.

[0023]

[Function] When manufacturing the photosensitive element, the protective film is
Since the photosensitive resin composition solution is applied on the support film and stretched after being heated and dried in a state where wrinkles are stretched and some tension is applied, the temperature of the photosensitive resin layer is in the range of 30 to 60 ° C. Since it will be laminated with and will be wound into a roll with distortion, after winding, the distortion will return with time, wrinkles, floats, folds on the protective film,
Problems such as peeling may occur. Further, since the photosensitive resin layer is flexible, it is easily affected by external pressure and heat, and in the case of the alkali development type, it is particularly susceptible to moisture absorption. ,
The photosensitive resin layer is easily deformed over time, and this deformation of the photosensitive resin layer also affects the protective film, causing defects such as wrinkles, floats, breaks, and peeling, and the photosensitive resin layer exudes from the edges of the photosensitive element. (Edge fusion) Inconvenience easily occurs. In the present invention, by using a protective film having a certain characteristic, the distortion of the protective film is relaxed and the deformation of the photosensitive resin layer is also prevented.

[0024]

EXAMPLES The present invention will now be described with reference to examples. Examples 1-5 and Comparative Examples 1-3 41% by weight of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer (53/30/17 (weight ratio), weight average molecular weight 100,000) methyl cellosolve / toluene ( 8
/ 2 (weight ratio)) solution 137 g (solid content 55 g), 2,
34 g of 2'-bis [(4-methacryloxypentaethoxy) phenyl] propane, 11 g of γ-chloro-β-hydroxypropyl-β'-methacryloyloxyethyl-o-phthalate, 2,2'-methylenebis (4-ethyl-). 6-t-butylphenol) 0.1 g, tribromomethylphenyl sulfone 1.2 g, 1,7-bis (9-
Acridinyl) heptane 0.2 g, benzyl dimethyl ketal 3 g, leuco crystal violet 1.0 g,
Malachite green (0.05 g), toluene (7 g), methyl ethyl ketone (13 g) and methanol (3 g) were blended to obtain a solution of an alkali developing type photosensitive resin composition.

A solution of this photosensitive resin composition was uniformly applied onto a polyethylene terephthalate film (PET) having a thickness of 20 μm as a support film, and dried for 10 minutes with a hot air convection dryer at 110 ° C. An oil layer was formed. By changing the coating thickness, three types of photosensitive resin layers having different thicknesses were formed. The film thickness of the photosensitive resin layer after drying was 50 μm, 160 μm, and 200 μm, respectively. In Example 5 only, a polypropylene film (OPP) having a thickness of 30 μm was used as a support film and dried for 20 minutes by a hot air convection dryer at 80 ° C. to form a photosensitive resin layer having a thickness of 150 μm.

Next, a polyethylene terephthalate film (PET) was used as a protective film on the photosensitive resin layers having various thicknesses shown in Table 1 in Examples 1, 2 and 5, and a polypropylene film (OPP) was used in Examples 3 and 4. ),
In Comparative Examples 1 to 3, a polyethylene film (PE) was laminated to form a photosensitive element. The obtained photosensitive element is cut into a width of 400 mm, a length of 60 m is wound around a core having an inner diameter of 75 mm in a roll shape so that the support film is on the outer side, and these roll-shaped photosensitive elements are attached to a substrate. Peelability of protective film at the time of matching, 30 ° C-
The presence or absence of wrinkles, folds, edge fusion and the like of the photosensitive element when stored in 90% RH for 5 days was examined. The results are shown in Tables 1 and 2.

[0027]

[Table 1]

[0028]

[Table 2]

The elastic modulus of each film is ASTM-D8.
82. Specifically, for PET and OPP, the test piece size is 15 mm (width) x 70 mm (length), the chuck distance is 50 mm, and the pulling speed is 10 mm /
The elongation of the obtained SS curve is 1
It was determined by the slope up to%. In the case of PE, it was determined in the same manner as above except that the pulling speed was 50 mm / min.
In addition, when sampling the test piece of each film, it sampled so that the winding direction of each film (roll form) and the length direction of the test piece may become parallel. The melting point of each film is 20 mg by DSC.
(PET, OPP), 10 mg (PE), heating rate 20 ° C
/ Min (PET, OPP), 10 ° C / min (PE). As is apparent from Tables 1 and 2, the photosensitive element using a plastic film having a modulus of elasticity of 110 kg / mm ² or more and a melting point of 160 ° C. or more as a protective film has significantly improved storage stability. Do you get it.

[0030]

INDUSTRIAL APPLICABILITY The photosensitive element of the present invention is excellent in storage stability without causing problems such as wrinkles, folds, peeling, and edge fusion during storage. Also books
The photosensitive element of the invention has the above-mentioned effect and has a concave surface.
It can be suitably used in the fields requiring adherends with large convexities and thick film patterns .

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoyoshi Tanno 4-13-1, Higashimachi, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Semiconductor & Liquid Crystal Materials Division Development Center (72) Inventor Kazuo Kobayashi Hitachi, Ibaraki Prefecture 4-13-1, Higashi-machi, Ichi, Hitachi Chemical Co., Ltd. (72) Inventor Hajime Kakumaru 4-13-1, 1-3, Higashi-cho, Hitachi, Ibaraki Hitachi Chemical Co., Ltd. Yamazaki Plant (56) References Special Kaihei 9-5992 (JP, A) JP 9-127686 (JP, A) JP 9-90616 (JP, A) JP 9-76637 (JP, A) JP 5-142777 ( JP, A) JP 7-134400 (JP, A) JP 9-304926 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03F 7/11 G03F 7/004 B32B 7/02 H05K 3/06

Claims (5)

(57) [Claims] 1. A photosensitive element having a plastic film A, a photosensitive resin layer, and a plastic film B in this order for forming a photosensitive resin pattern on a substrate, wherein the plastic film A has an elastic modulus of 5.
0 kg / mm ² or more and a melting point of 130 ° C. or more, the plastic film A is a film that is removed when the substrates are bonded together, the plastic film B is a polyethylene terephthalate film or a polypropylene film, and thickness of 160-3
A photosensitive element that is 00 μm. 2. In a photosensitive element having a plastic film A, a photosensitive resin layer and a plastic film B in this order for forming a photosensitive resin pattern on a substrate, the plastic film A has an elastic coefficient of 5.
The plastic film A is 0 kg / mm ² or more and has a melting point of 130 ° C. or more, the plastic film A is a film that is removed when the substrates are bonded together, and the thickness of the photosensitive resin layer is 160.
A photosensitive element that is ˜300 μm. 3. A bonding method of a photosensitive element, characterized in that the photosensitive resin layer while peeling off the plastic film A photosensitive element according to claim 1 or 2, wherein bonding to the substrate. 4. A photosensitive element having a protective film, a photosensitive resin layer and a support film in this order, wherein the protective film is a plastic film having an elastic modulus of 50 kg / mm ² or more and a melting point of 130 ° C. or more, A photosensitive element in which the thickness of the photosensitive resin layer is 160 to 300 μm. 5. A method for laminating a photosensitive element, wherein a photosensitive resin layer is laminated on a substrate while the protective film of the photosensitive element according to claim 4 is peeled off.