JP3513659B2 - Photosensitive resin composition laminate - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photosensitive resin composition laminate, and more particularly to a photosensitive resin composition laminate capable of obtaining high resolution.

[0002]

2. Description of the Related Art Conventionally, a photosensitive resin composition laminate (photosensitive film) has been used for forming fine circuits in the fields of printed wiring board manufacturing and precision metal processing. That is, it is a method in which a photosensitive film is laminated on a substrate, exposed through a negative film (pattern mask), developed, and optionally plated, followed by etching, resist stripping and the like.

The photosensitive film is usually composed of a light-transmissive support film, a photosensitive resin layer and a protective film.
As a usage method, first peel off the protective film,
The photosensitive resin layer is pressure-bonded (laminated) so that it directly contacts the substrate, the patterned negative film is adhered onto the light-transmissive film, and actinic rays (often using ultraviolet rays) are irradiated (exposed), and then Generally, a resist pattern is formed (developed) by spraying an organic solvent or an alkaline aqueous solution to remove unnecessary portions, and then etching is performed using an aqueous solution of lead chloride. Particularly, from the standpoint of environmental problems, a developer using an alkaline aqueous solution is required.

In recent years, electronic devices have been reduced in size and weight, printed circuit boards have been required to have finer circuits, resist patterns have been made finer, and photosensitive films have been required to have higher resolution. There is. However, the conventional photosensitive film having a three-layer structure cannot satisfy the requirement. That is, since exposure is performed through a light-transmitting support film, the film thickness needs to be made as thin as possible for high resolution, but on the other hand, to some extent to serve as a support when applying a photosensitive resin. Self-retaining property is required, and generally a thickness of about 15 to 25 μm is required,
At present, it is not possible to meet the demand for higher resolution by using a conventional grade support film.

In response to these demands, various attempts have been made to achieve high resolution. For example, it is a method in which the support film is peeled off before exposure and the negative film is directly adhered onto the photosensitive resin layer. Normally, the photosensitive resin layer retains a certain degree of tackiness so that it adheres to the substrate.If this method is applied directly, the negative film and the photosensitive resin layer will adhere, making it difficult to remove the negative film and improving workability. Of the negative film, the negative resin is contaminated with the photosensitive resin, and the sensitivity is lowered due to air obstruction.

Therefore, in an attempt to improve this method, JP-A-61-31855 and JP-A-1-221735 have been proposed.
Japanese Unexamined Patent Publication No. 2-230149, etc.,
It has been practiced to use two or more photosensitive resin layers and to use a non-adhesive layer as a layer in direct contact with a negative film. However, this method requires a lot of coating work because the photosensitive resin layer is multi-layered, and is not effective in reducing the sensitivity.

As another method, on the photosensitive resin layer,
Attempts to solve these drawbacks by providing an intermediate layer,
JP-B-56-40824, JP-A-55-5010
72, Japanese Patent Publication No. 54-12215, Japanese Patent Laid-Open No. 4
7-469, JP-A-59-97138, JP-A-59-216141, JP-A-63-1979.
No. 42, etc. However, in all of these, an intermediate layer had to be provided between the support film and the photosensitive resin layer, coating was troublesome twice, and a thin intermediate layer was difficult to handle.

[0008]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and provides a photosensitive resin composition laminate having improved sensitivity, resolution, adhesion and the like.

[0009]

The present invention provides a photosensitive resin composition comprising a support film (a), a photosensitive resin layer (b) and a protective film (c), which comprises a support film (a).
Has a haze of 0.1 to 1.5% and a thickness of 10 to 30 μ.
m relating to the photosensitive resin composition laminate.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The support film (a) of the present invention is
It should be mentioned that the haze is transparent, but the haze representing the turbidity needs to be in the range of 0.1 to 1.5%. The haze is a value representing the turbidity, and the haze value H is obtained from the total transmittance T of the light irradiated by the lamp and transmitted through the sample and the transmittance D of the light diffused and scattered in the sample. Is H =
It is calculated as D / T × 100. These are JIS K
7105 and can be easily measured by a commercially available turbidimeter, for example, NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd. A support film having a haze of less than 0.1% is difficult to obtain, and a support film having a haze of more than 1.5% does not have the effect of improving sensitivity, resolution, adhesion and the like. As a support film having a haze of 0.1 to 1.5%,
Examples thereof include polyethylene terephthalate films such as high transparency film GS series manufactured by Teijin Ltd., M-310 series manufactured by Diafoil Hoechst, and Mylar D series manufactured by DuPont.

The thickness of the support film (a) is 10 to 30.
It is set in the range of μm, and when it exceeds 30 μm, the resolution is lowered and the cost is increased. Further, since the supporting film (a) is usually peeled off and discarded before the development, it is possible to reduce industrial waste. Not preferable from a viewpoint. Again 10
When the thickness is less than μm, the film is too soft and inconvenient to handle.

As the photosensitive resin layer (b) of the present invention, a known one can be used, and usually contains a binder polymer, a photopolymerization initiator and a polymerizable vinyl compound as essential components. As the binder polymer, an alkyl ester of (meth) acrylic acid [(meth) acrylic acid means methacrylic acid and acrylic acid. The same shall apply hereinafter] and a copolymer with a vinyl monomer copolymerizable therewith.

Examples of the alkyl ester of (meth) acrylic acid include (meth) acrylic acid methyl ester,
(Meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid 2-ethylhexyl ester and the like can be mentioned. Further, as the vinyl monomer copolymerizable with the (meth) acrylic acid alkyl ester, for example, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, Methacrylic acid glycidyl ester, 2,2
2-trifluoroethyl (meth) acrylate, 2,
2,3,3-tetrafluoropropyl (meth) acrylate acrylamide, diacetone acrylamide, styrene, vinyltoluene and the like can be mentioned. These copolymers can be used alone or in combination of two or more kinds. It is preferable to use two or more of these copolymers in combination.

When the photosensitive resin composition layer (b) is of the alkali-developable type, a binder polymer obtained by copolymerizing (meth) acrylic acid with the above-mentioned alkyl ester and vinyl monomer is usually used.

Examples of the photopolymerization initiator include benzophenone, N-N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N, N-tetramethyl-4,4'-diaminobenzophenone and 4-methoxy. -4'-Dimethylaminobenzophenone, 2-ethylanthraquinone, aromatic ketones such as phenanthrenequinone, benzoin methyl ether, benzoin ethyl ether, benzoin ether such as benzoin phenyl ether, benzoin such as methylbenzoin, ethylbenzoin, benzyldimethyl Benzyl derivative such as ketal,
2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5
-Di (m-methoxyphenyl) imidazole dimer, 2
-(O-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,
5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- ( 2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 2-
(P-Methylmercaptophenyl) -4,5-diphenylimidazole dimer, 2,4,5-triarylimidazole dimer, 9-phenylacridine, 1,7-
Examples thereof include acridine derivatives such as bis (9,9′-acridinyl) heptane. These may be used alone or in combination of two or more.

Examples of the photopolymerizable vinyl compound include urethane acrylate biscoat # 831 (trade name of Osaka Organic Chemical Industry Co., Ltd.), polyether type urethane acrylate BTG-A (trade name of Kyoeisha Oil and Fat Chemistry Co., Ltd.),
Urethane (meta) such as polyester type urethane acrylate D-200A (trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), urethane acrylate Photomer 6008 (trade name, manufactured by San Nopco Co., Ltd.), urethane diallylate Chemlink 9503 (trade name, manufactured by Sartoma Co., Ltd.) Acrylate and trimethylolpropane ethoxy triacrylate (SR-454,
Sartomer product name), trimethylolpropane propoxytriacrylate (R-924, Nippon Kayaku product name), polyethylene glycol di (meth) acrylate (having 2 to 14 ethylene groups), trimethylolpropane Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, polypropylene glycol di (meth) acrylate (the number of propylene groups is 2 to 2).
14), dipentaerythritol penta (meta)
Acrylate, dipentaerythritol hexa (meth)
Bisphenol A, a compound obtained by reacting an α, β-unsaturated carboxylic acid with a polyhydric alcohol such as acrylate
Bisphenol A dioxyethylene di (meth), such as dioxyethylene di (meth) acrylate, bisphenol A trioxyethylene di (meth) acrylate, bisphenol A decaoxyethylene di (meth) acrylate
Compounds obtained by adding α, β-unsaturated carboxylic acid to glycidyl group-containing compounds such as acrylate, trimethylolpropane triglycidyl ether triacrylate, bisphenol A diglycidyl ether acrylate, and polyvalent carboxylic acids such as phthalic anhydride And an esterification product of a substance having a hydroxyl group and an ethylenically unsaturated group such as β-hydroxyethyl (meth) acrylate, (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, Examples thereof include alkyl esters of (meth) acrylic acid such as (meth) acrylic acid 2-ethylhexyl ester.

Further, in the photosensitive resin layer (b), if necessary, a plasticizer, a dye, a pigment, an imaging agent, a filler, an adhesion-imparting agent, a stabilizer and the like can be used in combination. The thickness varies depending on the application, but the thickness after drying is 10 to 10.
It is preferably about 100 μm.

As the protective film (c) of the present invention, a polyester film, a polyolefin film or the like is generally used, but a polyethylene film is preferable in terms of price, flexibility, strength and hardness. Also, its thickness is
It is preferably 1.0 to 40 μm, and if it is less than 10 μm, the handling property tends to be poor, and if it exceeds 40 μm,
It tends to increase costs.

The photosensitive resin composition laminate (photosensitive film) of the present invention is usually (1) peeling the protective film while applying heat, pressure, etc. so that the photosensitive resin layer adheres to the substrate. Laminating, (2) placing the negative film on the support film, exposing through the negative film,
(3) It is used in a method of forming an image (resist pattern) by developing after peeling the supporting film.

The laminating step (1) is performed while the photosensitive resin layer is heated and softened by a heatable roll generally called a hot roll or a heating jacket called a heat shoe and a roll called a laminating roll.

The exposure step (2) is generally carried out by using a contact or non-contact type of exposure apparatus for exclusive use. As the lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a xenon lamp lamp, or the like that effectively radiates ultraviolet rays can be used.

Examples of the developing method (3) include a dipping method and a spray method, and the high pressure spray method is most suitable for achieving high resolution. The developing solution differs greatly between the solvent developing type and the alkali developing type, and it is general to use 1,1,1-trichloroethane for the solvent developing type and 1% by weight of sodium carbonate for the alkali developing type.

The processing after the image formation includes steps such as etching and plating, which may be carried out by known methods if necessary.

[0024]

EXAMPLES Next, the present invention will be described in more detail by way of examples, which should not be construed as limiting the invention.

Examples 1 to 3 and Comparative Examples 1 to 2 Methacrylic acid / methyl methacrylate / butyl methacrylate / 2-ethylhexyl acrylate copolymer (weight ratio 2
40% by weight methyl cellosolve / toluene (weight ratio 6/4) solution 1 of 5/50/5/20, weight average molecular weight 80,000)
50 g of 00 g (solid content 40 g), methacrylic acid / methyl methacrylate / ethyl acrylate / styrene copolymer (weight ratio 30/30/30/10, weight average molecular weight 40,000)
40% by weight of methyl cellosolve / toluene (weight ratio 8/2) solution (solid content 20 g), tribromomethylphenyl sulfone 1.0 g, leuco crystal violet 1
g, Malaikito Green 0.05 g, methyl ethyl ketone 10 g, toluene 10 g, methanol 3 g, benzophenone 4.5 g and N, N′-tetraethyl-4,
A solution was obtained by adding 0.2 g of 4'-diaminobenzophenone.

Next, the solution of this photosensitive resin composition was uniformly applied onto various polyethylene terephthalate films (supporting film (a)) shown in Table 1 and dried by a hot air convection dryer at 100 ° C. for about 10 minutes. After forming the photosensitive resin layer (b), a 30 μm thick polyethylene film was laminated as a protective film (c) to obtain a photosensitive film. The film thickness of the photosensitive resin layer after drying was 50 μm.

On the other hand, the copper surface of a copper-clad laminate (MCL-E-61 manufactured by Hitachi Chemical Co., Ltd.), which is a glass epoxy material in which copper foil (thickness 35 μm) is laminated on both sides, is # 600.
Polishing using a polishing machine (manufactured by Sankei Co., Ltd.) having an appropriate brush, washing with water, and drying with an air stream, heating the obtained copper-clad laminate to 80 ° C., and exposing the copper surface to the above-mentioned photosensitivity. The resin composition layer was heated to 120 ° C. and laminated while peeling off the polyethylene film.

Then, a negative film (pattern mask) is placed on the polyethylene terephthalate film,
3kw high-pressure mercury lamp (HMW-201, manufactured by Oak Manufacturing Co., Ltd.)
In B), an exposure of 60 mJ / cm2 was performed. At this time, in order to evaluate the photosensitivity, a region where the amount of light transmission is gradually reduced in the negative film (where the optical density is 0.05 is the first step, and the optical density is increased by 0.15 step by step). Tablet). In addition, the line / space is at least 30 μm
The negative film for resolution evaluation has a comb pattern in which both the line and the space increase every 10 μm, and the adhesiveness has a comb pattern in which the line / space is a minimum of 30 μm / 400 μm and only the line increases every 10 μm. A negative film for evaluation was also used for exposure.

Then, the polyethylene terephthalate film was removed, and an unexposed portion was removed by spraying a 1 wt% sodium carbonate aqueous solution at 30 ° C. for 50 seconds. Further, the photosensitivity of the photosensitive resin composition was evaluated by measuring the number of steps of the step tablets of the photocured film formed on the copper-clad laminate, and the results are shown in Table 1. The light sensitivity is indicated by the number of steps of the step tablet, and the higher the number of steps of this step tablet, the higher the light sensitivity.

The resolution is represented by the resolution (μm) of the comb pattern for every 10 μm, and the smaller the value of this resolution, the higher the resolution. Adhesion is expressed by the width (μm) of the line remaining without peeling after development. The smaller the value of this adhesion, the closer the line adheres to the copper-clad laminate without peeling from the copper-clad laminate. Therefore, it indicates that the adhesiveness is high. The results are also summarized in Table 1.
It was shown to.

[0031]

[Table 1]

[0032]

The photosensitive resin composition laminate of the present invention is excellent in sensitivity, resolution, adhesion and the like.

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-5-11439 (JP, A) JP-A-3-134669 (JP, A) JP-A-60-262156 (JP, A) JP-A-3- 83625 (JP, A) JP-A-2-83546 (JP, A) Patent 3452597 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03F ^7/ 00-7/42

Claims (3)

(57) [Claims] 1. A photosensitive resin composition comprising a support film (a), a photosensitive resin layer (b) and a protective film (c), wherein the support film (a) has a haze of 0.1 to 0.1.
1.5%, the thickness is 10 to 30 μm, and
The photosensitive resin layer (b) contains a binder polymer, a photopolymerization initiator and a polymerizable vinyl compound as essential components, and the copolymer to be blended as the binder polymer is a copolymer of at least two types. A blended mixture, wherein the at least two types of copolymers are copolymers obtained by copolymerizing (meth) acrylic acid and an alkyl ester of (meth) acrylic acid, and (meth) acrylic acid and (meth), respectively. A photosensitive resin composition laminate which is a copolymer obtained by copolymerizing an acrylic acid alkyl ester and a vinyl monomer copolymerizable therewith. 2. The photosensitive resin composition laminate according to claim 1, which contains styrene as the vinyl monomer. 3. The thickness of the photosensitive resin layer (b) after drying is 1
It is 0-100 micrometers, The photosensitive resin composition laminated body of Claim 1 or Claim 2.