JPH03100071A - Positive photosensitive cationic electrodeposition coating resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give a resist pattern of a high resolution in high sensitivity by compounding a specified amount of a specified (meth)acrylic resin with a specified amount of a specified compound. CONSTITUTION:The title composition comprises 30-95 pts.wt. (meth)acrylic resin obtained by copolymerizing essential components of a polymerizable monomer of formula I (wherein R<1> is H or CH3; R<2-3> are each H or an alkyl; and (n) is 1-6) and a polymerizable monomer which can give a homopolymer of a glass transition point <=60 deg.C (e.g. n-butyl acrylate) and 70-5 pts.wt. compound of formula II (wherein R<4> is an alkyl, R<5> is R<2>, an alkoxy or a nitro; R<6> is a group of formula III or IV; (m) is 0-2, (n) is 1-3; and (m+n)=1-3).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a positive photosensitive cationic electrodeposition paint resin composition used for forming resist patterns in the manufacture of printed circuit boards and the like.

(Prior Art) Conventionally, as a method of forming a resist pattern on the surface of a substrate, a method is often used in which a photosensitive layer is formed on the surface of the substrate, and then actinic rays are irradiated, followed by a photosensitive layer. Various methods are employed for forming the photosensitive layer in this step.

For example, a method using a photosensitive resin composition solution (coating liquid) such as dip coating, roll coating, or curtain coating, or a method in which a photosensitive layer is previously formed on a base film (hereinafter referred to as photosensitive film) is applied to the substrate surface. A method of laminating layers using a laminator or the like is known. Among these methods, the method using a photosensitive film is currently being adopted as the mainstream method in the field of printed circuit board manufacturing because it can easily form a photosensitive layer with a uniform thickness.

(Problems to be Solved by the Invention) Recently, as printed circuit boards have become denser and more precise, resist patterns of higher quality have become necessary. That is, it is desired that the resist pattern be free of pinholes and that is in close contact with the surface of the underlying substrate. It is known that the currently mainstream method of laminating photosensitive films has limitations in meeting such demands. This method eliminates dents and uneven polishing during substrate manufacturing.

It is difficult to follow the unevenness of the substrate surface caused by uneven copper plating on the surface of the mesh 2 of the glass cloth in the inner layer of the substrate, so it is necessary to conduct this layer under reduced pressure to obtain sufficient adhesion. This problem can be avoided to some extent by using the method (see Japanese Publication No. 59-3740), but this requires special and expensive equipment.

For these reasons, solution coating methods such as dip coating, roll coating, and curtain coating have been reconsidered in recent years.

However, with these methods, it is difficult to control the film thickness.

There are problems such as insufficient uniformity of film thickness and occurrence of pinholes.

Recently, a new method of forming a photoresist film by electrodeposition coating has been proposed (Japanese Patent Laid-Open No. 62-23549
(See Publication No. 6). According to this method, ■The adhesion of the resist is improved. ■It follows the unevenness of the substrate surface well. ■ It is possible to form a photoresist film with a uniform thickness in a short time. ■The coating liquid is an aqueous solution, so there is no contamination of the working environment. It has the advantage of being preventable and causing no problems in terms of disaster prevention. Furthermore, if the electrodeposition paint is a cationic type, the coating film (photoresist film) obtained by the electrodeposition coating will not contain metal ions, and problems such as residual stains can be prevented, which is preferable.

Several proposals have been made in the past regarding positive photosensitive cationic electrodeposition paints that are considered to be particularly effective in manufacturing printed circuit boards having through holes. Most of them are of the type in which a photosensitive group of 1,2-naphthoquinonediazide is introduced into the polymer molecule (for example, JP-A-61-20629
No. 3, JP-A-63-221178, JP-A-64-46
From the viewpoint of electrodeposition coating, these methods have the advantage of easy control of the electrodeposition solution, but on the other hand.

From the standpoint of positive photoresists, there were problems such as insufficient photosensitive characteristics, low mechanical strength of the resist film, and furthermore, it was difficult to finely adjust each photoresist's characteristics.

On the other hand, IC-? When forming a positive photoresist using a solution coating method used in the manufacturing process of semiconductor devices such as LSI, most of the composition of the positive photoresist used is alkali-soluble resin such as novolac resin or vinyl phenol resin. It is a mixture of a photosensitive material typified by an ester compound of benzophenone having two or more hydroxy groups and 1,2-naphthoquinonediazide sulfonic acid (for example, JP-A-63-3053).
No. 48, JP-A-63-279246, JP-A-64-1
No. 1259, Japanese Unexamined Patent Publication No. 17049/1983). These resins have good photosensitive properties and mechanical properties of the resist film when viewed from the performance as positive photoresists, but this is natural because these resins do not have amine groups that are essential for cationic electrodeposition paints. However, it cannot be used as an electrodeposition paint as it is.

Furthermore, the resin that is the main component of the photoresist used in the manufacture of printed circuit boards, which is the main application of the present invention, has traditionally been a (meth)acrylic resin because of its physical properties and ease of handling. However, the ester compound of benzophenone having two or more hydroxyl groups and 1,2-naphthoquinonediazide sulfonic acid, which is widely used as a photosensitive material, is (meth).
Since it has extremely poor compatibility with acrylic resins, it cannot be used in combination with (meth)acrylic resins as the main component of photosensitive materials.

As described above, the positive photoresist compositions formed by electrodeposition coating that have been proposed to date have problems such as low photosensitivity and mechanical properties of the resist film, and furthermore, it is difficult to finely adjust the properties. Although positive photoresists formed by a coating method using a liquid solution have good properties, it has been impossible to convert them into electrodeposition paints for various reasons.

(Means for Solving the Problems) Therefore, as a result of intensive studies, the present inventors have developed an amine group-containing resin for use in a cationic electrodeposition coating.

We selected a (meth)acrylic resin, which is commonly used as the main component of photoresists currently used in the manufacture of printed circuit boards, and in order to make the (meth)acrylic resin an excellent electrodeposition coating, the glass transition point of the homopolymer was It is essential to copolymerize a polymerizable monomer at 0° C. or lower, and there is no conventional compatibility with the (meth)acrylic resin obtained in this way.

We have successfully discovered a positive photosensitive cationic electrodeposition paint resin composition that can be formed by electrodeposition by combining with a photosensitive material and has excellent photosensitive properties and mechanical properties of a resist film.

That is, 9 the present invention provides (a) polymerizable heptamer-7 represented by general formula (I)
17,1 (wherein, R1 is hydrogen or a methyl group, R2 and R3 are each independently hydrogen or an alkyl group, nll11-6
) and the glass transition point of the homopolymer is 0℃
The total amount of (meth)acrylic resin copolymerized with the following polymerizable hexamer as an essential component and (b) is 100%.
30 to 95 parts by weight and (b) a compound represented by general formula (II) (wherein R4 is an alkyl group, H and s are hydrogen, and an alkyl group).

Alkoxy group or nitro group Ba represents 0 Q, 1m is an integer of O to 2, n is an integer of 1 to 3, and 1
The sum of m and n is selected to be an integer from 1 to 3) (a
) and (b) in an amount of 5 to 70 parts by weight based on a total of 100 parts by weight.

According to the present invention, it is possible to provide a positive photoresist that is more suitable for electrodeposition coating than ever before and has excellent photosensitivity and mechanical properties of the resist. can take full advantage of the advantages of

Below, nine aspects of the present invention will be described in detail.

The (meth)acrylic resin which is the component (a) first requires the use of a polymerizable monomer represented by the general formula (I3).

As the polymerizable monomer represented by general formula (I).

For example, aminoethyl (meth)acrylate, N-te
rt-butylaminoethyl (meth)acrylate), N,
N-dimethylaminoethyl (meth)acrylate), N,
N-diethylaminoethyl (meth)acrylate, N,
N-dimethylaminopropyl (meth)acrylate,
Examples include N,N-dimethylaminobutyl (meth)acrylate. These can be used alone or in combination of two or more.

The amount of the polymerizable monomer represented by the general formula (I) used is preferably 4 to 60 parts by weight based on 100 parts by weight of the total amount of copolymerizable monomers forming the polymer (a), More preferably, the amount is 10 to 40 parts by weight. If the amount used is less than 4 parts by weight, the present invention is applied after adding an acid to the positive photosensitive cationic electrodeposition coating resin composition as described below.

When water is added and dispersed, the water dispersibility and water dispersion stability are poor and the composition tends to settle, and if the amount used exceeds 60 parts by weight of tJma1, the appearance of the coating after electrodeposition will be poor. There is.

Another essential component of the (meth)acrylic resin, which is component (a), is a polymerizable monomer whose homopolymer glass transition point is 0° C. or lower. A polymerizable monomer whose homopolymer glass transition point is 0°C or lower means that the glass transition point of a polymer obtained by homopolymerizing the monomer is 0°C or lower. The glass transition point is measured by a conventional thermal analysis method, but preferably by differential scanning calorimetry (D
EC). Here, the homopolymer has a glass transition point of 0° C. or lower.

Ethyl acrylate, inpropyl acrylate.

n-propyl acrylate, inbutyl acrylate,
There are n-hexyl methacrylate, n-octyl methacrylate, n-decyl methacrylate, etc. Among them, n-
-butyl acrylate and 2-ethylhexyl acrylate are preferred. Two or more of these polymerizable heptamers may be used in combination even if they are 1's, and the amount used is equal to the total amount of copolymerized monomers forming the polymer component (a).
The amount is preferably 5 to 75 parts by weight per 00 parts by weight.

More preferably, the amount is 20 to 60 parts by weight.

When the amount used is less than 1 part by 5 parts, the glass transition point of the polymer becomes high, and there is a possibility that a film may not be formed when the electrodeposition paint combined with the photosensitive material (component (b)) is electrodeposited. If the amount exceeds 75 parts by weight, the glass transition point of the polymer will be too low, and the coating film after electrodeposition will tend to have a large smudge.

The (meth)acrylic resin, which is the component (a), includes, in addition to the above polymerizable monomers, for example, methyl acrylate.

Methyl methacrylate, ethyl methacrylate.

Butyl methacrylate, cyclohexyl methacrylate, tetrahedral furfuryl methacrylate.

2.2.2-) Lifluoroethyl methacrylate, diacetone acrylamide, acrylonitrile, styrene,
Copolymerization can be carried out by using one or more kinds of monomerizable monomers such as vinyltoluene in combination. The amount used is (a
) The total amount of copolymerized monomers forming the resin component 1
It can be used in an amount of 91 parts by weight or less relative to 00 parts by weight.

Synthesis of (meth)acrylic resin which is component (a) is as follows.

The polymerizable monomer can be obtained by general solution polymerization in an organic solvent using a polymerization initiator such as azobisisobutyronitrile, azobisdimethylvaleronitrile, or benzoyl peroxide. In this case, the organic solvent to be used is preferably a hydrophilic organic solvent such as dioxane, methoxyethanol, ethoxyethanol, diethylene glycol, etc., considering that it will be used in an electrodeposition coating. If a hydrophobic organic solvent such as toluene, xylene, or benzene is mainly used, it is necessary to distill off the solvent after resin synthesis and replace it with the hydrophilic organic solvent. The average molecular weight of the resin (in terms of standard polystyrene) is s, ooo ~ 150
．． A range of 000 is preferred.

If it is less than s, o o o, the mechanical strength of the resist is weak.

If it exceeds 150,000, the electrodeposition coating properties tend to be poor and the appearance of the coating film tends to be poor.

The amount of (meth)acrylic resin used as component (a) is (
30 to 95 parts by weight per 100 parts by weight of the total amount of al and (b)
Parts by weight. The amount is preferably 50 to 90 parts by weight. If the amount used is less than 30 parts by weight, the water dispersibility and water dispersion stability in the electrodeposition bath will be poor, and if it exceeds 95 parts by weight (b
The proportion of the photosensitive material, which is a component of 1, decreases, and the sensitivity to light decreases.

Next, the compound represented by the general formula (I[), which is the component (b), will be explained.

R4 in the general formula Cl1l is an alkyl group, preferably an alkyl group having 1 to 18 carbon atoms, especially an alkyl group having 1 to 18 carbon atoms.
The alkyl group 9 of 12 is preferably a methyl, n-propyl, isopropyl, n-octyl, 2-ethylhexyl, n-dodecyl group, or the like.

Moreover, R8 is hydrogen, methyl, ethyl, or n-propyl.

Isopropyl, n-butyl, isobutyl, t-butyl,
Alkyl groups such as n-hexyl, methoxy.

Any one is selected from alkoxy groups such as ethoxy, tetraboxy, butoxy groups, and nitro groups.

0 Q It is.

and an integer of mtio~2, n is an integer of 1 to 3, and 9
The sum of m and n is selected to be an integer from 1 to 3.

The method for synthesizing the compound of general formula (I[) is not particularly limited, but preferably trihydroxybenzoic acid ester (e.g. gallic acid ester), dihydroxybenzoic acid ester, hydroxybenzoic acid ester (e.g. salicylic acid ester)
It can be obtained by condensing benzoic acid ester derivatives having a hydroxyl group on the benzene ring with 1,2-benzoquinonediazide-4-sulfonic acid chloride or 2-naphthoquinonediazide-5-sulfonic acid chloride. To give an example of isomerism, benzoic acid ester derivatives having a hydroxyl group on the benzene ring and 1,2-
An organic solvent is added to a mixture of benzoquinonediazide-4-sulfonic acid chloride or Fil, 2-nandoquinonediazide-5-sulfonic acid chloride, and while stirring, triethylamine, pyridine, and sodium carbonate (for boat fishing) are added. Add a base such as an aqueous solution (9) dropwise.
After the addition, the mixture is stirred for an additional 10 minutes to 8 hours to react. During this time, the temperature is room temperature to 80℃, 4IK 30 to 50℃
It is preferable to keep it within this range.

In this manner, benzoquinonediazide sulfonic acid chloride or naphthoquinonediazide sulfonic acid chloride may be entirely condensed with respect to the hydroxyl group, or a portion of the hydroxyl group may be left and the remainder may be condensed. As can be seen from the above-mentioned synthesis examples, K may be obtained as a mixture of compounds having different amounts of unreacted hydroxyl groups in one molecule, but it is often necessary to isolate them.

In any case, K is a compound of general formula (II) selected such that m is an integer of θ to 2, n is an integer of 1 to 3, and the sum of 1m and n is an integer of 1 to 3. If so, the scope of the present invention falls within the scope of the present invention whether they are used singly or as a mixture.

The amount of the compound of general formula (II), which is the component (b), is 5 to 70 parts by weight per 100 parts by weight of the total amount of (a) and (b).
Parts by weight. More preferably, the amount is 10 to 50 parts by weight. If the amount used is less than 5 parts by weight, the sensitivity to light will decrease, and if it exceeds 70 parts by weight, water dispersibility and water dispersion stability in an electrodeposition bath will deteriorate.

In addition to the above-mentioned components (a) and (b), the positive recording photosensitive cationic electrodeposition coating resin composition of the present invention may contain a small amount of a quinonediazide compound that is used in ordinary positive recording photosensitive resin compositions. I can do it.

As this quinonediazide compound, 0, for example, λ3.4-
) Lihydroxypenzophenone-1,2-+7 toquinone diazido 5-sulfonic acid ester.

211'-tetrahydroxybenzophenone-1゜2-
Examples include 1,2-naphthoquinonediazide-5-sulfonic acid esters of polyhydroxybenzophenone such as naphthoquinonediazide-5-sulfonic acid ester. The usage amount of these quinonediazide compounds is (
Based on a total of 100 parts by weight of components a) and fb). 10
Parts by weight or less are preferred. If it exceeds 10 parts by weight, the compatibility with the (meth)acrylic resin of component (a) tends to decrease, and the water dispersion stability tends to decrease.

Furthermore, a sensitizer can also be blended into the positive dust photosensitive cationic electrodeposition coating resin composition of the present invention.

Examples of the sensitizer include pyrrole, imidazole,
Nitrogen-containing compounds having active hydrogen such as triazole, indole, benzimidazole, oxazolidone, piperidone, hydantoin, glycine, barbylic acid and derivatives thereof can be mentioned. The amount of the sensitizer to be used is preferably 30 parts by weight or less based on 100 parts by weight of the total amount of components (a) and (b). 30
If the amount exceeds 1 part by weight, the solubility of the resist during printing increases and the remaining film rate tends to decrease.

In the positive photosensitive cationic electrodeposition coating resin composition of the present invention, dyes, St additives, plasticizers, adhesion promoters, inorganic fillers, etc. can also be used as appropriate.

In order to make the positive photosensitive cationic electrodeposition paint resin composition of the present invention containing the above-mentioned components (a) and (b) as main components into an electrodeposition paint, K is (a) and (b). component.

Further, although it is desirable that the various components mentioned above, which are used as necessary, are uniformly dissolved in the hydrophilic organic solvent, it is not necessary to be particular about this. The hydrophilic organic solvent mentioned here includes, for example, dioxane, methoxyethanol, ethoxyethanol, diethylene glycol, and the like. These solvents may be used alone or in combination of two or more, and the amount used is preferably 300 parts by weight or less per 100 parts by weight of the total solid content.

Next, add acid to this solution (al component (meth))
Neutralizing the amine groups contained in the acrylic resin facilitates water solubilization or water dispersion of the Kyokai composition. Examples of the acid used here include acetic acid, lactic acid, phosphoric acid, etc., although there are no particular limitations.

These can be used alone or in combination of 281 or more. The amount of these acids used is component (a) (meth)
0.4 to 1 per amino group in the acrylic resin.
0 equivalents are preferred. If the amount is less than 0.4 equivalent, the water dispersion stability in the electrodeposition coating bath will decrease, and if it exceeds 1.0 equivalent, the coating film (photosensitive layer) thickness after electrodeposition will become thinner) and the storage stability will decrease. Preferably, water is then added to step 1 to dissolve or disperse the positive photosensitive cationic electrodeposition coating resin composition in water to prepare an electrodeposition coating bath. The solid content of the electrodeposition coating bath is usually 5 to 20% by weight, and the pH
is preferably in the range of 3 to 9.

If the pH is less than 3, however, the electrodeposited film may be redissolved and no film may be formed as a result, while if the pH exceeds 9, dispersion may deteriorate and electrophoresis may become difficult.

In order to adjust the pH to the above-mentioned preferred range, the above-mentioned acid may be added later to adjust the pH.

In addition, nonionic additives are used to improve the water dispersibility and dispersion stability of positive photosensitive cationic electrodeposition paint resin compositions.

Surfactants such as cations and anions can also be added as appropriate.

Furthermore, a hydrophobic solvent such as toluene, xylene, or 2-ethylhexyl alcohol can be added as appropriate to increase the coating amount during electrodeposition coating.

The electrodeposition coating bath thus obtained was used to coat the substrate surface (
In this case, the substrate surface is iron or aluminum.

To electrocoat a substrate (which must be covered with metals such as copper, zinc, and other metals and alloys), the substrate is immersed in an electrocoat bath as a cathode, and a DC voltage of usually 50 to 400 V is applied. is applied for 10 seconds to 5 minutes. At this time, it is desirable to control the temperature of the electrodeposition coating bath at 15 to 30°C.

After electrodeposition coating, the object to be coated is taken out of the electrodeposition coating bath, washed with water, drained, and then dried with hot air. At this time, if the drying temperature is high, there is a risk that the quinonediazide complex in the positive photosensitive cationic electrodeposition paint resin composition will decompose.
It is preferable to dry it below.

The thickness of the coating film (photosensitive layer) obtained in this way is 2 to 50 μm.
is preferred. If the film thickness is less than 2 μm, the liquid resistance will be low;
Furthermore, when used in the manufacture of printed circuit boards, for example, when a resist pattern is formed and then etched, it tends to have poor etching solution resistance and etch factor, and if the film thickness exceeds 50 μm, the resist pattern may be difficult to dissolve. The level may decrease.

Next, the coating film is imagewise irradiated with actinic rays to photodecompose the exposed areas, and then the exposed areas are removed to obtain a resist pattern.

Examples of active light sources include those that emit light with a wavelength of 300 to 450 nm9, such as a mercury vapor arc.

Carbon arc, xenon arc, etc. are preferably used.

This is done by spraying alkaline water such as IJum, sodium carbonate, potassium hydroxide, etc., or by immersing it in alkaline water.

(Example) The present invention will be explained below with reference to Examples.

First, a method for synthesizing component (a) and component (b) used in Examples will be described.

<Synthesis of (meth)acrylic resin with al component (a-1) Add dioxane 9009 to a flask equipped with a stirrer, a reflux condenser, a dropping funnel with two thermometers, and a nitrogen gas introduction tube,
While stirring, nitrogen gas was blown into the mixture and the mixture was heated to a temperature of 90°C. When the temperature became constant at 90°C, N,N-dimethylaminoethyl acrylate 1509. A mixture of methyl methacrylate 3009, 2-ethylhexyl acrylate 5509, and azobisisobutyronitrile 109 was added dropwise into the flask over 2.5 hours, and then kept at 90° C. with constant stirring for 3 hours. After 3 hours, add 3 g of azobisisobutyronitrile to dioxane 1009
was added dropwise into the flask over 10 minutes, and then kept at 90° C. for 4 hours with stirring.

The weight average molecular weight of the resin as component (a) obtained by K in this way was 49,000. The amine value was 59. The solid content of the resin solution was 50.5% by weight.

Xane 11309 was added, and while stirring, nitrogen gas was blown into the mixture and the mixture was heated to 90°C. When the temperature became constant at 90°C, N,N-diethylaminoethyl methacrylate 1309. Methyl methacrylate 3309. n
-Butyl acrylate 4609.2-Hydroxyethyl acrylate 809 and azobisisobutyronitrile 1
The mixed solution of 09 was added dropwise into the flask over 25 hours, and then kept at 90° C. with stirring for 3 hours. After 3 hours, add 3g of azobisin butyronitrile to 10% of dioxane.
The solution dissolved in 0.06 was added dropwise into the flask over 10 minutes, and then kept at 90° C. for 4 hours while stirring.

The weight average molecular weight of the resin, component (a), thus obtained was 61,000. The amine value is 40, which is a good thing. The solid content of the resin solution was 45.1% by weight.

Synthesis of photosensitive material of component (b) (b-1) -n-propyl gallate 21.2 g (0.1 moJ)
and 53.7 g of 1,2-naphthoquinonediazide-5-sulfonic acid chloride (0.2 moI dioxane 5
00dK solution was heated to 40℃ while stirring,
Triethylamine 219 was added dropwise to this over 30 minutes. After the dropwise addition, the reaction was further carried out at 40°C for 3 hours, and then 1 reactant was reduced to 0. The resulting precipitate was purified and filtered to obtain an ester compound of n-propyl gallate and 1,2-naphthoquinonediazide-5-sulfonic acid 55.
Get g.

(b-2) 2-ethylhexyl gallate 28.29 (0.1 mo
A solution of 80.4 g (0.3 mar) of 1,2-naphthoquinonediazide-5-sulfonic acid chloride dissolved in 800 g of dioxane was heated to 40°C with stirring, and triethylamine 329 was added to it for 30 minutes. It dripped. After the dropwise addition, the reaction was further carried out at 40°C for 3 hours. The precipitate obtained was purified, treated with P and treated with 2-ethylhexyl gallate in 1.
Ester compound 919 with 2-naphthoquinonediazide-5-sulfonic acid was obtained.

Example 1 80 g of resin solution of (a-1) (solid content 4O, 491K
8 g of the photosensitive material (b-1) and 1.4 g of acetic acid were dissolved, and then 400 g of water was slowly added dropwise to disperse the solution in water to obtain an electrodeposition bath (pH 6.2).

Example 2 80 g (solid content 40.49) of the resin solution of (a-1) K(
b-2) C) Photosensitive material 12 s and U vinegar e 1.4 g
Once completely dissolved, 400 g of water was slowly added dropwise and dispersed in water to obtain an electrodeposition bath (pH 6.1).

Example 3 To 90 g (solid content 40.69) of the resin solution of (a-2) was added (
b-1) Photosensitive material 109 and acetic acid 0.99 were dissolved and then 400 g of water was slowly added dropwise to disperse the solution in water to obtain an electrodeposition bath (pH 5.9).

Example 4 90 g of resin solution (a-2) (solid content 40.69) I
Dissolve 5 g of photosensitive material c(b-2) and 0.9 g of acetic acid and
Next, 400 g of water was added dropwise to disperse the solution in water to obtain an electrodeposition bath (pH 6.0).

A stainless steel plate (8U8304) (shape 200 mm
75 mm x 1 tm) was immersed as an anode at 25°C.
A DC voltage of 150 V was applied for 3 minutes at a temperature of 150 V to form an electrodeposition coating film (photoresist film) on the surface of the steel clad laminate. Thereafter, it was washed with water, drained, and dried at 80° C. for 15 minutes. The film thickness after drying was about 8 μm in all Examples 1 to 4.

These coatings were then imagewise exposed to a 3 kW ultra-high pressure mercury lamp through a photomask, and after death, 1 liter of carbon dioxide was added (IJ).
It was lightly soaked in an aqueous solution of aluminum. In order to evaluate the photosensitivity at this time, a step tablet (a photomask with an optical density of 0.05 as the first stage and an optical density increasing by 0.15 for each stage is used) was used for exposure to obtain three stages. As a result of measuring the amount, it was found that all examples had a high sensitivity of 100 mJ/am''. It was also confirmed that the obtained resist patterns all had a high resolution of 50 μm.

(Effects of the Invention) The positive photosensitive cationic electrodeposition paint resin composition of the present invention provides an electrodeposition paint that can fully exhibit the advantages of forming a 7-otoresist by electrodeposition coating, and thereby has high sensitivity. It is possible to form a resist pattern with high resolution.

By using the positive photosensitive cationic electrodeposition paint resin composition of the present invention, it can be used as a resist relief 7, or can be used to form an etching or plating 7 resist using a steel clad laminate as a base.

Claims (1)

[Claims] 1. (a) Polymerizable monomer represented by the general formula (I) ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ (I) (In the formula, R^1 is hydrogen or a methyl group, R^ 2 and R^3
are each independently hydrogen or an alkyl group, n is an integer of 1 to 6) and a polymerizable monomer whose homopolymer glass transition point is 0°C or lower are copolymerized as essential components (
30 to 95 parts by weight of meth) acrylic resin based on 100 parts by weight of the total amount of (a) and (b) and (b) the compound represented by general formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ( II) (In the formula, R^4 is an alkyl group, R^5 is hydrogen, an alkyl group, an alkoxy group, or a nitro group, and R^6 is a ▲ mathematical formula, chemical formula, table, etc.▼ or ▲ mathematical formula, chemical formula, table, etc. There is ▼, m is an integer from 0 to 2, n is an integer from 1 to 3,
The sum of m and n is selected to be an integer from 1 to 3) (a
A positive type photosensitive cationic electrodeposition coating resin composition containing 5 to 70 parts by weight based on 100 parts by weight of the total amount of (a) and (b). 2. The positive-working photosensitive cationic electrodeposition coating resin composition according to claim 1, wherein the polymerizable monomer whose homopolymer has a glass transition point of 0 DEG C. or lower is n-butyl acrylate and/or 2-ethylhexyl acrylate. 3. The positive-working photosensitive cationic electrodeposition coating resin composition according to claim 1 or 2, wherein R^4 in the compound represented by general formula (II) is an alkyl group having 1 to 12 carbon atoms.