JPH03119014A - Negative type dry film photoresist composition - Google Patents

Abstract

PURPOSE:To obtain the title composition providing printed circuit board having excellent flexibility, adhesivity, shelf stability and chemical resistance by blending a specific block copolymer, photopolymerizable unsaturated monomer and photopolymerization initiator in a specific ratio. CONSTITUTION:(A) 95-5 pts.wt. block copolymer of AB type or ABA type consisting of a polymer chain segment which comprises a radical-polymerizable unsaturated monomer not containing carboxyl group and has 20-5,000 polymerization degree and a polymer chain segment which comprises a radical- polymerizable unsaturated monomer having >=40mol% carboxyl group-containing radical-polymerizable unsaturated monomer and has 20-5,000 polymerization degree is blended with (B) 5-95 pts.wt. polymerizable unsaturated monomer and (C) 0.01-20 pts.wt. one or more of photopolymerization initiator, photo- crosslinking agent and photosensitizer to give the objective composition.

Description

Detailed Description of the Invention (a) Object of the Invention (Field of Industrial Application) The present invention relates to a laminated type alkaline development type negative dry film photoresist used for forming printed circuits and images by etching. Regarding the composition.

(Prior Art) In recent years, a so-called dry film resist (hereinafter sometimes referred to as Kano R) consisting of a support layer and a photopolymerizable composition layer has been used as a resist for producing printed circuits.
is widely used.

DFR generally has a structure in which a photopolymerizable composition is laminated on a support film, and in many cases, a protective film is further laminated on the same composition.

As the photopolymerizable composition, there are known an alkali-developable type in which the uncured portion is removed with an alkaline aqueous solution and a solvent-developable type in which the uncured portion is removed with an organic solvent.

The method for creating a printed circuit using alkaline development type DFR is as follows. That is, first, after peeling off the protective film, the photocurable composition layer (resist film) is laminated so as to be in contact with the printed circuit board substrate. Next, after exposure through a mask film, etc., the support film is peeled off or removed as necessary, and uncured portions are removed and developed with an alkaline aqueous solution such as a sodium carbonate aqueous solution.
A hardened resist image is formed on the substrate. Using the image formed in this way as a resist pattern, the surface of the copper foil film on the substrate is etched or plated, and then the hardened resist image is developed using a developer such as a sodium hydroxide solution that is stronger than the above-mentioned developer (sodium carbonate solution, etc.). A printed circuit is obtained by peeling and removing with an alkaline aqueous solution.

In the above process, the unexposed photopolymerizable composition layer has sufficient adhesion to the copper surface of the printed circuit board, and the photopolymerizable composition layer after lamination does not peel off from the copper surface; It maintains sufficient adhesion even in the process of etching or plating as a resist pattern, and prevents the copper plate pattern from flowing due to the etching solution soaking in due to the resist pattern lifting from the copper surface, or plating due to the plating solution soaking in. It is necessary that no slipping occurs.

In order to conform to the irregularities of the printed circuit and improve adhesion, the photopolymerizable composition film may be softened. One of the softening methods includes adding a plasticizer or increasing the amount of photopolymerizable monomer. However, such plasticization using a low-molecular-weight compound has problems such as contamination due to component bleed and reduced peelability of the support film and protective film, and is therefore not a preferred method.

Another method is to impart flexibility by plasticizing the high molecular weight resin component itself. When trying to impart flexibility to a resin, the glass transition point (Tg) of the resin ends up lowering.

Therefore, when a resist film is wound up into a roll and stored, there is a problem of edge facing, in which the resist layer oozes out from the edges of the roll over time. Furthermore, there are problems in that the storage stability in summer deteriorates, and the resistance to etching liquids and plating liquids also deteriorates.

(Problem to be solved by the invention) In short, conventional negative dry film photoresist compositions are flexible and adhesive, do not cause contamination due to edge facing or stickiness, and have excellent storage stability.
However, the present invention aims to provide a negative-working dry film photoresist composition that has improved chemical resistance.

(b) Structure of the invention (means for solving the problems) The negative dry film photoresist composition of the invention has (a) a carboxyl group (containing anhydrous carboxyl group);
a polymer chain segment with a degree of polymerization of 20 to 5,000 formed from a radically polymerizable unsaturated monomer that does not have any Degree of polymerization formed from radically polymerizable unsaturated monomer containing %
95 to 5 parts by weight of an AB type or ABA type block copolymer containing ~5000 polymer chain segments, (b)
Containing 5 to 95 parts by weight of a photopolymerizable unsaturated monomer, and (c) 0.01 to 20 parts by weight of at least one selected from a photopolymerization initiator, a photocrosslinking agent, and a photosensitizer. It is a composition.

The term "rABA type block copolymer" described herein includes not only ABA type block copolymers but also ABAB type and ABABA... type block copolymers.

Further, in the AB type or ABA type block copolymer of the present invention, any polymer chain segment is A (therefore, it is also B).
).

The radically polymerizable unsaturated monomer (one monomer) having no carboxyl group (including anhydrous carboxyl group; the same shall apply hereinafter) in the block copolymer of the present invention is typically represented by Ml, and has a carboxyl group. When a radically polymerizable unsaturated monomer (one monomer) containing at least 40 mol% of a radically polymerizable unsaturated monomer is typically represented by M2, the radically polymerizable unsaturated monomer having no carboxyl group in the present invention Polymerization degree formed from unsaturated monomers: 20-5ooo
The polymer chain segment can be represented by the formula +-M I → Te (where the degree of polymerization m=20 to 5000). Furthermore, a polymer chain segment with a degree of polymerization of 20 to 5000 formed from a radically polymerizable unsaturated monomer containing at least 40 mol% of a radically polymerizable unsaturated monomer having a carboxyl group has the formula +-M'' +7 (in the formula, degree of polymerization n
= 20 to 5000).

The AB type or ABA type block copolymer of the present invention can be expressed using such a schematic method as follows:
It can be represented by the following formulas, and each block copolymer represented by these formulas is a copolymer that can be used in the present invention (in the formula, m, n, i, j,
(l is a number representing the degree of polymerization within the range of 20 to 5000).

Between + and 1→Ko "÷Mz÷-" ←M1→-1-←M2→1 "6Ml→Ko4-M2→1
-I M1-+-r-+-M2→-Choichi+-M'→-r+
M 2→-r+M'→Ko÷M"+7-+ M'h+
M ” −) −+ M ′ +r−fM ”7→M1su11 ””10M” Juice+M1go+M27→M17→M2
→T...The 1+-M1→Co' segment, which is one of the components constituting the block copolymer of the present invention, is formed by polymerizing a radically polymerizable unsaturated monomer that does not have a carboxyl group. However, the monomer thereof is disclosed in JP-A-61-287915 and JP-A-64-266.
Among the monomers described in Publication No. 19, any monomers containing no carboxyl group can be used. Specific examples of the monomer include acrylic esters (for example, methyl acrylate, butyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, etc.), methacrylic esters (for example, methyl methacrylate, ethyl methacrylate, glycidyl methacrylate, 2-ethylhexyl methacrylate, etc.), other acrylic or methacrylic compounds (e.g. acrylonitrile, methacrylateril, acrylamide, etc.), styrenic compounds (e.g. styrene, α-
methylstyrene, etc.), various other vinyl compounds (eg, vinyl acetate, vinylpyrrolidone, etc.), and conjugated diene compounds (eg, butadiene, isoprene, etc.).

Further, the above-mentioned +M''-)-- segment, which is the other component constituting the block copolymer of the present invention, contains at least 4 radically polymerizable unsaturated monomers having a carboxyl group.
It is formed by polymerizing a radically polymerizable monomer containing 0 mol%.

Examples of the monomer include unsaturated basic acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, and cinnamic acid, and unsaturated dibasic acids such as maleic acid, fumaric acid, and maleic anhydride. .

In the case of the aforementioned unsaturated dibasic acids such as maleic acid, homopolymerization cannot be achieved by radical polymerization, but copolymerization can be achieved by mixing alternatingly polymerizable monomers such as styrene, acrylic esters, and methacrylic esters. Can be polymerized. By mixing such alternating polymerizable monomers and copolymerizing an unsaturated dibasic acid, the +M''-)- of the present invention can be obtained.
When forming the r-segment, it is necessary to use a monomer mixture containing at least 40 mole percent of the unsaturated dibasic acid.

As a method for producing the block copolymer of the present invention, as disclosed in JP-A No. 64-26619,
There is a photopolymerization method using a compound having a dithiocarbamate group as an initiator.

As the initiator having a dithiocarbamate group, A
Examples of the monofunctional dithiocarbamate compound that provides the B-type block copolymer include n-butyl-N, N-dimethyldithiocarbamate, and benzyl-N-ethyldithiocarbamate.

In addition, examples of trifunctional dithiocarbamate initiators that give ABA type block copolymers include N, N, N, N
'-Tetramethylthiuram tetrasulfide, N, N,
N,N-tetraethylthiuram tetrasulfide, Cp-xylene bis(N,N-dimethyldithiocarbamate)], and trifunctional dithiocarbamate compounds include, for example, 1,2.3-1-
Examples of tetrafunctional dithiocarbamate compounds include (1,2,4,5-tetrakis(N,N-diethyldithiocarbamylmethyl)benzene) and the like. It will be done.

Further, the block copolymer of the present invention is disclosed in Japanese Patent Application Laid-Open No. 61-28
It can also be produced by a method using a polymeric peroxide or a polymeric azo compound, as described in Japanese Patent No. 7915.

Examples of the polymeric peroxide include compounds represented by the following formula (in the formula, n =
4.5).

However, the former method using a dithiocarbamate compound as an initiator is preferable because less homopolymer by-products are produced.

The photopolymerizable unsaturated monomer (b) in the present invention is, for example, a monovalent or divalent or more polyhydric alcohol.

Examples include monofunctional or polyfunctional monomers obtained by reacting β-unsaturated carboxylic acids. As the -functional monomer, for example, diethylene glycol ethyl ether (meth)acrylate [(meth)acrylate is a general term for "acrylate" and "methacrylate". ), tetraethylene glycol phenyl ether (meth)acrylate, etc.

In addition, examples of the bifunctional monomer include polyethylene glycol di(meth)acrylate (ethylene glycol number 2 to 14), polypropylene glycol di(meth)acrylate (propylene glycol number 2 to 14)
, trimethylolbroban di(meth)acrylate, 2
．． Examples include those obtained by adding ethylene oxide or propylene oxide to 2-bis(4,4-dihydroxycyphel)propane or 4,4-dihydroxydiphenylmethane, and further esterifying acrylic acid or methacrylic acid.

In addition, examples of the trifunctional monomer include trimethylolpropane tri(meth)acrylate, tetramethylo-! Examples include methane tri(meth)acrylate, and its tetrafunctional monomer includes tetramethylolmethanetetra(meth)acrylate.

Furthermore, as the photopolymerizable unsaturated monomer (b) in the present invention, α is a glycidyl group-containing compound.

Compounds obtained by addition reaction of β-unsaturated carboxylic acids, such as bisphenol A diglycidyl ether di(
meth)acrylates, phenylglycidyl ether (meth)acrylates can also be used, as well as polyhydric carboxylic acids, such as succinic anhydride, and compounds with hydroxyl groups and ethylenically unsaturated groups, such as β-hydroxyethyl (meth)acrylate. An esterified product of can also be used.

Various components can be used as the component (c) in the present invention, that is, a photopolymerization initiator, a photocrosslinking agent, and a photosensitizer. As a photo-crosslinking agent, even Haku. 6-bis (4'
Examples include azide compounds such as -azidobenzal)cyclohexanone, bis(4-azidobenzal)acetone, and 4.4-diazidostilbene.

Examples of the photosensitizer or photopolymerization initiator include 2-ethylanthraquinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,
2-benzanthraquinone, 2,3-penzanthraquinone, 2-phenylanthraquinone, 2.3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1.
4-naphthoquinone, 9.10-phenanthraquinone, 2
- Quinones such as methyl 1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone; benzophenone, Michler's ketone [4
,4-bis(diethylamino)benzophenone), 4
．． Aromatic ketones such as 4-bis(dimethylamino)benzophenone; benyne ethers such as benzoin, benzoin methyl ether, benzoin ethyl ethyl, benzoin phenyl ether, methylbenzoin, and ethylbenzoin; dimethylthioxanthone and dimethylaminobenzoic acid; Examples include combinations of thioxanthone compounds and tertiary amine compounds, such as combinations of thioxanthone compounds and tertiary amine compounds.

The blending ratio of each component in the photoresist composition of the present invention is such that component (a) is 95 to 5 parts by weight, component (b) is 5 to 95 parts by weight, and component (C) is 0.01 to 5 parts by weight. 20
Parts by weight.

The photoresist composition of the present invention may preferably contain a radical polymerization inhibitor in order to improve its thermal stability and storage stability. Examples of the radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, ter
t-Butylcatechol, cuprous chloride, 2.6-sheet t
ert-butyl-p-cresol, 2,2-methylenebis(4-ethyl-5-tert-butylphenol)
, 2,2-methylenebis(4-methyl-5-tert-
butylphenol), etc.

Further, the photoresist composition of the present invention may contain coloring substances such as dyes and pigments. Examples of the coloring substance include Tsuksin, Auramine Base, Chalcoxide Green S1 Balamadienta, Crystal Bioleft, Methyl Orange, Nile Blue 2B, Victoria Pure Blue, Masorachite Green, Bay) Tsuku Blue 20, and the like.

Furthermore, the photoresist composition of the present invention may contain various additives such as a plasticizer, if necessary.

The support used when forming a photopolymerizable composition layer (dry film photoresist composition layer) using the photoresist composition of the present invention is preferably a transparent support that transmits active light.

Examples of the support include polyethylene terephthalate, polyvinyl alcohol, polyvinyl chloride, vinyl chloride copolymers, polyvinylidene chloride, vinylidene chloride copolymers, polymethyl methacrylate, polymethyl methacrylate copolymers, and polystyrene. , polyacrylonitrile, styrene copolymers, polyamides, cellulose derivatives, and various other resins, all of which are in film form.

If necessary, a protective layer can be laminated on the surface of the photopolymerizable composition layer formed on the support and made of the photoresist composition of the present invention. An important characteristic of the protective layer is that the adhesive force between the protective layer and the photopolymerizable composition layer is sufficiently smaller than the adhesive force between the support and the photopolymerizable composition layer, and the protective layer can be easily formed. It is possible to peel it off. As the protective layer, for example, a polyethylene film, a polypropylene film, a film with excellent releasability described in JP-A-59-202457, etc. can be used.

The thickness of the photopolymerizable composition layer using the photoresist composition of the present invention varies depending on the use etc., but in the case of manufacturing printed circuit boards, it is 5 to 100μ, preferably 5 to 70μ, and the thinner the layer, the more the photoresist composition of the present invention is used. Resolution improves.

The process of manufacturing a printed circuit board using the alkaline development type DFR of the present invention is similar to a conventional method, and the process will be briefly described below.

First, after peeling off the protective layer, the photopolymerizable composition layer is laminated by heat and pressure bonding to the metal surface of the printed circuit board substrate.

The heating temperature at this time is generally 80 to 150°C. Then, if necessary, the support layer is peeled off and imagewise exposed to actinic light through a mask film. Next, if the support layer has not been peeled off, it is peeled off and removed, and unexposed areas are removed using an alkaline aqueous solution and developed. As the alkaline aqueous solution, an aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. is appropriately selected and used in relation to the characteristics of the photopolymerizable composition layer. Aqueous sodium carbonate solution is used. Then, using the developed hardened resist image as a mask, a metal image pattern is formed on the exposed metal surface using known methods such as etching and/or plating. Thereafter, the cured resist image is generally treated with an alkaline aqueous solution stronger than the alkaline aqueous solution used for the phenomenon and removed. The aqueous stripping solution is -
Aqueous solutions of sodium hydroxide and potassium hydroxide are used for boat fishing. Note that a small amount of a water-soluble organic solvent can be added to this stripping solution or the above-mentioned developer, if necessary.

By using a specific AB type or ABA type block copolymer as the polymer resin component, the negative dry film photoresist composition of the present invention has excellent flexibility and adhesion to metals, and moreover, it can be used at room temperature. It was possible to obtain a material that does not cause adhesion or edge fading and has excellent etching liquid resistance and plating liquid resistance. For this reason, in the process of manufacturing printed circuit boards etc. using the photoresist composition of the present invention, peeling and lifting of the resist layer will not occur, and pattern deterioration and peeling in the etching and plating process, and plating peeling. Since no phenomenon occurs, pattern accuracy can be improved, fine patterning can be achieved, and the incidence of defective products can be reduced.

(Examples, etc.) The present invention will be described in more detail below with reference to copolymer synthesis examples, working examples, and comparative examples, but the present invention is not limited to these examples.

Copolymer synthesis example 1 p-xylylene bis(N,N-diethyldithiocarbame θ2.Og represented by the structural formula methyl methacrylate 368
g, 168 g of hydroxyethyl acrylate was added and dissolved, placed in 12 containers made of Pyrex glass, the remaining substrate in the container was sufficiently replaced with nitrogen gas, and the container was tightly capped.
400W ultraviolet lamp (manufactured by Toshiba Lightic Co., Ltd. 400
At a position 15 cm away from the L mercury lamp), approximately 1
Ultraviolet rays were irradiated for 0 hours. The amount of produced polymer was 528 g, and its number average molecular weight (Mn) as determined by gel permeation chromatography was 108,200 and weight average molecular weight (Mw) was 201,000.

Next, acrylic M 60 was added to 240 g of this produced polymer.
g and 300 g of toluene were added, mixed well to dissolve, and then irradiated with ultraviolet rays for 10 hours under the same conditions as above to perform polymerization. The resulting solution was purified by reprecipitation using 201 hexane and further dried under reduced pressure.

The amount of polymer produced was 288 g, and its molecular weight was 125.000 for Mn and 256.000 for Mw. In addition, this polymer has a blocking rate of 88.0%.
The acid value was 156.

This block copolymer was an ABA type block copolymer, and the degree of polymerization of block A was 80 and the degree of polymerization of block B was 870.

Copolymer Synthesis Example 2 368 g of methyl methacrylate and 168 g of hydroxyethyl acrylate were added and dissolved, and then used as a polymerization initiator, average degree of condensation represented by the structural formula n = 4.5, theoretical active oxygen amount = 3.96, Selected polymeric peroxide with a 10-hour half-life temperature of 63.5°C (Japanese Patent Application Laid-Open No. 61-287915
After stirring well, the mixture was placed in a flask containing 1200 g of toluene, and polymerization was carried out at 60 to 80°C for 5 hours.

Next, 120 g of acrylic acid was added to this, and the polymerization temperature was set to 7.
Polymerization was continued for 10 hours at 0-85°C.

This solution was purified by reprecipitation using 36β hexane, and the polymer was dried under reduced pressure. The amount of polymer produced is 623
g, its Mn is 105.000, and its Mw is 334
．． 000, the blocking rate was 63%, and the acid value was 143.

This block copolymer was an AB type block copolymer, and the degree of polymerization of block A was 690 and the degree of polymerization of block B was 130.

Copolymer Synthesis Example 3 To 0.6 g of benzyl-N,N-diethyldithiocarbamate represented by the structural formula, 280 g of methyl methacrylate, 20 g of glycidyl methacrylate were added and dissolved, and the mixture was placed in a Pyrex glass 11 flask and placed in a container. After the remaining substrate was sufficiently replaced with nitrogen gas, it was sealed and irradiated with ultraviolet rays for about 10 hours using a 400 W ultraviolet lamp (the same one used in Synthesis Example 1) at a position 10 lights away. The number average molecular weight Mn of the produced resin was 6.8 x 10', and the weight average molecular weight Mw was 12.2 x 10'.

To this product, 100 g of 2-ethylhexyl acrylate was further added, and after nitrogen substitution in the same manner, ultraviolet ray irradiation was performed. Mn=8.4X10', Mw of the resulting resin
=16. OXl 0'.

To this product, 400 g of toluene was added, and further 120 g of acrylic acid was added, the atmosphere was replaced with nitrogen in the same way, and the product was irradiated with ultraviolet rays. After that, the product was purified by the reprecipitation method using 201 hexane, and dried to obtain 491 g of resin. Obtained. Mn of this resin
= 1.04X10', Mw=2.25X10
', and the blocking rate is 87%, 7. ) Polymerization degree force (140? Ah 9.4' 7 bubbles.

The degree of polymerization was 110\.

Copolymer Synthesis Example 4 368 g of methyl methacrylate, 168 g of hydroxyethyl acrylate, and 120 g of acrylic acid were added to 1 part of toluene.
200 g and added 9 g of azobisisobutyronitrile. After nitrogen gas was passed through this solution to sufficiently replace oxygen with nitrogen gas, the solution was reacted at 80° C. for 10 hours.

This solution was purified by reprecipitation using 36N hexane and dried under reduced pressure.

The amount of polymer produced is 570g, and its Mn is 106.000
, Mn was 329.000. This resin was a random copolymer and had an acid value of 78.

Example 1 A photosensitive resist solution having the following composition was prepared.

Benzophenone 3.1g Victoria Pure Blue Methyl Ethyl Ketone Ethyl Cellosolve*1...Shin Nakamura Chemical Co., Ltd. trade name 0.1g 0 g 5 g PE-4 This solution was applied to a uniform film thickness on a 25μ thick polyethylene terephthalate film. , and dried with hot air at 100°C for 3 hours. The thickness of the photosensitive resist film layer after drying was 30μ.

Next, a 30 μm thick polyethylene film was laminated onto the photosensitive resist film layer as a protective film, and then wound up into a roll to obtain a dry film photoresist.

Laminate the above dry film photoresist onto a copper-clad glass epoxy substrate while peeling off the polyethylene protective film at a lamination temperature of 105°C and a pressure of 3 kg/c.
It was crimped with la. The resist film adhered well to the substrate and did not peel off even when pulled by hand.

Next, the photoresist layer of the substrate on which this photoresist was adhered was passed through a negative mask film with a pattern drawn on it, and was exposed to a 3kHz high-pressure mercury lamp from a distance of 90cm.
Exposure was made for 0 seconds. After exposure, the polyethylene terephthalate support film was peeled off, a 2% by weight aqueous sodium carbonate solution at 25° C. was sprayed for 40 seconds, the unexposed areas were removed, and the film was developed. The resulting resist image had a resolution up to a line width of 50 microns.

Next, the copper surface was soft etched and then cleaned.

That is, the substrate was immersed in a 25% aqueous solution of Enplate PC-455 (trade name, Japan Metal Finishing Co., Ltd.) at 50° C. for 3 minutes. Next, after washing with water, a 15% aqueous solution of ammonium persulfate was kept at 25°C, and the developed substrate was immersed in this aqueous solution for 1 minute and then taken out. After washing with water, it was further immersed in a 2% aqueous sulfuric acid solution kept at 25°C. After being immersed in water for 1 minute, it was taken out and washed with water.

Next, "copper sulfate conc" (200 g of copper sulfate dissolved in 14 pure water) was diluted 3.6 times with 19% sulfuric acid in a plating solution at a current density of 2.5 A/dm2 at room temperature. I did plating for 30 minutes.

Next, plating was performed at 2 A/dm2 for 10 minutes using a solder plating liquid (trade name: Toptainer NF) manufactured by Okuno Pharmaceutical Industries.

During each of the above operations, the resist film was not damaged or peeled off, and exhibited good chemical resistance. Furthermore, since there was no peeling off at the edges of the resist image, there was no plating missing, and a precise circuit pattern could be drawn.

Further, when the roll-shaped dry film resist obtained in this example was left for one week at 40° C., no resin oozing from the edges (F-shift facing) was observed.

Example 2 The block copolymer obtained in Synthesis Example 2 was used instead of the block copolymer obtained in Synthesis Example 1, and a circuit was formed on a copper-clad glass epoxy substrate in the same manner as in Example 1. A printed circuit board was produced in the same manner.

In this case as well, the resist film adhered well to the substrate and did not peel off even when pulled by hand. Further, the resist image had a resolution up to a line width of 60 μm. Furthermore, during the soft etching, copper plating, and solder plating steps, the resist film was not damaged or peeled off, showed good chemical resistance, and no plating was observed to peel off. Furthermore, when the roll-shaped dry film was left to stand in the same manner as in Example 1, no resin bleeding was observed from the edges.Example 3 The blocks obtained in Synthesis Example 1 A photosensitive resist solution was prepared in the same manner as in Example 1 except that the block copolymer obtained in Synthesis Example 3 was used instead of the polymer and 0.3 g of undecylimidazole was used. was coated so that the resist film layer coating had a thickness of 20 μm, and otherwise the resist film was pasted on a copper-clad glass epoxy substrate under the same conditions as in Example 1, and exposed and developed in the same manner to obtain a resist image. The resist image was heated at 100° C. for 15 minutes to cause the glycidyl groups and carboxylic acid groups to react and crosslink. As a result, the strength and chemical resistance of the resist film could be improved even though the thickness of the resist film was small.

In this case as well, the resist film adhered well to the substrate and did not peel off even when pulled by hand. Also, the resist image is 4
It had a resolution down to 0μ.

Furthermore, during the soft etching, copper plating, and solder plating steps, the resist film was not damaged or peeled off, showed good chemical resistance, and no plating was observed to peel off. Furthermore, as in Example 1, no resin bleeding from the edges of the dry film was observed.

Comparative Example 1 A dry film resist was produced in the same manner as in Example 1 except that the random copolymer obtained in Synthesis Example 4 was used instead of the block copolymer obtained in Synthesis Example 1. A circuit was formed on a copper-clad glass epoxy board under the same conditions as in Example 1.

In this case, since the adhesion between the resist film and the substrate was poor, when the resist film was pulled by hand, it peeled off. The resolution of the resist image was only up to 150μ. In addition, since the resist film has low strength, soft etching,
During the copper plating and solder plating processes, the film was likely to be damaged or peeled off, resulting in a high incidence of defective products. In addition, burrowing was also observed. Further, when the roll-shaped dry film was left at 40° C. for one week, some resin was observed to ooze out from the edges.

(C) Effects of the Invention The dry film photoresist composition of the present invention has excellent flexibility and adhesion, does not cause sticking or edge facing at room temperature, and has excellent resistance to etching liquids and plating liquids. When used in the manufacture of printed circuit boards, pattern accuracy can be improved and there are fewer defective products.

Claims (1)

[Claims] (1) (a) A polymer chain segment with a degree of polymerization of 20 to 5,000 formed from a radically polymerizable unsaturated monomer that does not have a carboxyl group (including an anhydride carboxyl group) and a carboxyl group (including an anhydride carboxyl group). ) and a polymer chain segment with a degree of polymerization of 20 to 5,000 formed from a radically polymerizable unsaturated monomer containing at least 40 mol% of a radically polymerizable unsaturated monomer having
95 to 5 parts by weight of type or ABA type block copolymer, (b) 5 to 95 parts by weight of photopolymerizable unsaturated monomer, and (c) photoinitiator, photocrosslinking agent, and photosensitizer. A negative dry film photoresist composition containing 0.01 to 20 parts by weight of at least one selected from the following.