JPH03281622A - Photocurable diallyl phthalate resin composition and printed circuit board prepared by using the same - Google Patents

Abstract

PURPOSE:To obtain the title composition desirable as a UV exposure- developable, plating-reaction-resistant solder resist, essentially consisting of a diallyl phthalate prepolymer, a polyfunctional unsaturated compound, a photopolymerization initiator, an epoxy resin, an epoxy curing agent, a UV absorber, an antifoamer, a filler and a solvent. CONSTITUTION:A photocurable diallyl phthalate resin composition essentially consisting of diallyl phthalate prepolymer, a polyfunctional unsaturated compound, a photopolymerization initiator, an epoxy resin, a specified epoxy curing agent, a UV absorber, an antifoamer, a filler, a solvent for dissolving the above diallyl phthalate prepolymer and the above epoxy resin, suited as a solder resist excellent in applicability, contact exposure properties, developability, offset resistance, plating dissolution resistance, plating reaction resistance (so- called cathode peeling resistance), electrical insulation and heat resistance and being capable of forming a pattern by UV exposure and solvent development.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a photocurable diallyl phthalate resin composition used in the production of printed circuit boards, and a method for applying the same to ultraviolet (UV) exposure and development type plating reactivity. The present invention relates to a method of manufacturing a printed circuit board using a solder resist.

[Conventional technology]

Conventional UV exposure and development type solder resists for printed circuit boards include, for example, Japanese Patent Publication No. 5], -40451, and Japanese Patent Publication No. 52-
No. 30969, JP-A-60-208377, JP-A-Sho 6
2-4390, JP-A No. 62-253613, and the like. Such a resist was mainly used in the method of manufacturing a printed board shown in FIG. FIG. 2 shows the subtract method manufacturing process using a four-layer board as an example. In this process, starting material is a copper-clad laminate with an inner layer formed and copper foil laminated on the top and bottom surfaces, holes are drilled at predetermined positions, a catalyst is applied, and then electrical mesh plating is applied to the entire surface including the through holes. A predetermined circuit pattern is formed by etching, and finally a solder resist is applied. Epoxy resin-based thermosetting solder resists, which are pattern-formed by screen printing, have long been used as such solder resists, but as the wiring density of printed circuit boards increases, UV exposure and development with good coating accuracy has been used. A type of solder resist was developed.

On the other hand, in the part-reactive printed board manufacturing method shown in FIG. 1, it is essential to use a plating-resistant solder resist that has completely different characteristics from the solder resist used in the subtract method shown in FIG.

In the part-reactive method, unlike the subtract method, holes are made at predetermined positions in a copper-clad laminate, a catalyst is applied, and a conductor circuit is first formed. Next, a plating-resistant reactive solder resist is formed in predetermined areas, and finally, chemical copper plating is used to plate only necessary areas such as through-holes and land areas.

This manufacturing method has the advantage of being cheaper and more accurate than the subtract method. The process is simplified because it does not plate the entire surface as in the subtract method, but only partially plating where it is needed, and etching only the thin copper foil of the copper-clad laminate when forming the conductor circuit. It is simple, has low loss, and enables high-precision wiring. In the part-reactive method, the potential of chemical copper plating on the wiring pattern under the plating-resistant solder resist is -0.6 to -0.6.
Since it can be used as a permanent resist even after going through the harsh process of being immersed in a high-temperature, strong alkaline plating solution at -0.9V for a long time, it needs to have the function of a solder resist. As a plating-resistant solder resist suitable for such a purpose, a thermosetting type based on a boxy resin in which a pattern is formed by screen printing has been known. A solder resist having such plating resistance is disclosed in JP-A-58-147416. In addition, conventional UV exposure/development type resists with plating resistance, such as JP-A-62-265321, do not take bleed-through resistance into consideration at all, so when UV irradiation is carried out to print a pattern with a negative mask in close contact, both sides are exposed simultaneously. Exposure was not possible, and workability was poor because the exposure work was done one side at a time. In addition, it was found that heat resistance was still insufficient due to the increasing requirements for process margins and soldering conditions.

[Problem to be solved by the invention]

In the above conventional technology, for example, the UV exposure and development type resist described in Japanese Patent Publication No. 52-30969 has no plating reactivity at all in order to be used in the part-reactive method.
The solder resist described in JP-A-58-147416 has plating resistance, but because it is not a UV exposure and development type, it is not possible to form patterns with high precision, and there is no consideration given to show-through resistance, making it difficult to work. There were problems such as inferiority.

The first object of the present invention is to provide a photocurable diallyl phthalate resin composition for use in a UV exposure and development type plating-resistant reactive solder resist that can be used in a part-additive method. That is, there are a wide variety of properties that a practical resist should have, and if even one of them is lacking, its practicality will be significantly impaired. Therefore, an object of the present invention is simply to provide a resist that simultaneously satisfies many properties that cannot be obtained by combining conventional techniques. A list of such issues is as follows.

a) It is essential that the resist of the present invention be cured with UV light. That is, 300~ suitable for manufacturing printed circuit boards.
Irradiation with 400 nm ultraviolet (UV) light causes a crosslinking reaction, and only the irradiated portions need to be cured. Further, it is necessary to cure the resin within a practical range of 0.02 to IOJ/d as the irradiation amount.

b) It is essential that the resist of the present invention has an appropriate difference in solubility in a developing solution between a portion cured by UV irradiation and an uncured portion, and has good developability, so-called resolution after development.

C) It is essential that the resist of the present invention can be applied to both sides of a printed circuit board and exposed normally on both sides at the same time. That is, there must be no so-called show-through, in which UV light exposed from one side passes through the resist and the base material and hardens the resist on the other side.

If this problem is not solved, the difference in the negative mask patterns used on both sides of the base material will also appear on the opposite side.
It seriously impairs practicality.

d) In order to improve the resolution of the resist of the present invention, it is essential that the negative mask can be exposed in close contact with the resist without any problem during the 0-inch exposure. With resists that do not solve this problem, the resist sticks to the negative mask due to its own viscosity or softening due to the rise in temperature during exposure.

In such a case, the negative mask must be cleaned after each exposure, which significantly impairs practicality. Therefore, even if the negative mask is brought into close contact with the resist and exposed, it is essential that the resist does not stick to the mask.

e) It is essential that the resist of the present invention has good coating properties. In other words, when applying a resist to the entire surface of a printed circuit board using a screen printing method or a roll coater, it not only has the characteristics of an appropriate ink that provides a uniform thickness and does not leave voids, but also has the characteristics of an appropriate ink that can be used during the work. It is necessary that the values do not change.

f) The resist of the present invention is formed on a printed circuit board as a product, and it is essential that it has good heat resistance to withstand repeated soldering.

That is, about 10 seconds of solder immersion at about 280°C
Even if repeated 0 times, or equivalent hot air, infrared rays,
It is necessary that abnormalities such as blistering and peeling do not occur in the resist on the printed circuit board even when soldering with a soldering agent or the like.

g) The resist of the present invention is formed on a printed circuit board as a product, and it is essential that it can maintain high 1I4A edge properties. That is, it is necessary to maintain excellent insulation properties that do not cause insulation deterioration between wirings, especially insulation properties when moisture is absorbed.

h) The resist of the present invention is formed on a printed circuit board as a product, and it is essential that it has excellent chemical resistance. That is, it is necessary that the resist is not dissolved or deteriorated by solvents used in franking, cleaning, soldering, etc. during printed circuit board mounting.

i) After the resist of the present invention is formed on a printed circuit board, it is essential that it has good alkali resistance and plating reaction resistance, so-called cathode peeling resistance. Specifically, the chemical mesh plating solution is high temperature, highly alkaline and -0.6~
Even when immersed for a long time in severe conditions with a deposition potential of -0.9V, the resist surface must not dissolve or change in quality, and furthermore, it must not peel off on the base material or conductor circuit. More specifically, when applying chemical copper plating, it is essential that no peeling or deterioration of adhesion between the circuit copper foil and the resist occurs.

Although the mechanism leading to sm is not entirely clear, it seems to be as follows. As a result of various studies, we found that peeling was observed only in the resist applied on the conductor circuit connected to the areas where the chemical net plating reaction was occurring, and that the conductor circuit copper foil was oxidized before the resist was applied. The resist peels off in an extremely short time. Further, it will not peel off unless a so-called plating deposition potential (-0.6 to -0.9 V) is applied to a portion where the conductor circuit is completely covered with resist.

As a result of these events, moisture passes through the resist film during plating and reaches the interface with the circuit copper foil, and the copper oxide on the surface of the circuit copper foil is reduced by the deposition potential.

The bond with the resist is broken and separation occurs. this is.

Unlike the conventional plating resistance of resist, it is distinguished as plating reactivity resistance (cathode peeling resistance). We discovered that it is important to prevent the formation of copper oxide on circuit copper foils during printed circuit board manufacturing, and we addressed this by limiting the resist composition.

This problem is the most important point to keep in mind when manufacturing printed circuit boards using the part additive method. If this problem is not resolved, the resist on the circuit copper foil will peel off.
It becomes completely impractical.

j) The resist of the present invention must have so-called plating elution resistance, that is, no harmful components will be eluted or extracted from the resist into the plating solution when chemical net plating is applied after being formed on a printed circuit board.

If such problems are unresolved, components eluted or extracted from the resist will have an adverse effect on the plating precipitation reaction, resulting in the plating reaction being stopped or delayed, and the physical properties of the deposited copper significantly deteriorating.

It is essential to avoid such problems. A second object of the present invention is to provide U, which is made of a predetermined photocurable diallyl phthalate resin composition that satisfies all of the above problems a) to j).
It is an object of the present invention to provide a method for manufacturing a printed circuit board by a part-reactive method using a V-exposure and development type force-plated resist. Furthermore, a third object of the present invention is to provide a printed circuit board manufactured by such a method.

Furthermore, a fourth object of the present invention is to provide an electronic device using the printed circuit board of the present invention.

[Means to solve the problem]

In order to achieve the above object, the present invention uses the following as a plating-resistant solder resist composition, a so-called photocurable diallyl phthalate resin composition. A prepolymer of diallyl phthalate, a polyfunctional unsaturated compound, a photopolymerization initiator, an epoxy resin, a predetermined epoxy curing agent, an ultraviolet absorber, an antifoaming agent, a filler, and the prepolymer of diallyl phthalate. It contains a polymer and an organic solvent for dissolving the epoxy resin.

The diallyl phthalate prepolymer of the present invention is also referred to as a β-polymer, and its detailed manufacturing method and properties are described, for example, in Naoki Yoshimi, "Diallyl Phthalate Resin," Nikkan Kogyo Shimbun Sha Series (1972). The molecular weight of the prepolymer essential to the present invention is preferably 3,000 to 30,000. If it is less than 3,000, the adhesion exposure property with a negative mask will be poor, and if it is more than 30,000, the developability will be poor.

Further, the statement that a prepolymer is included does not preclude the inclusion of a small amount of diallyl phthalate monomer or three-dimensional network-structured γ-polymer that remains or is produced during polymer synthesis.

Further, the polyfunctional unsaturated compound in the composition of the present invention is a compound having at least two or more ethylene bonds in the molecule. For example, it can be obtained by an esterification reaction between an unsaturated carboxylic acid and a divalent or higher polyhydroxy compound.

Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, etc.
Examples of the polyhydroxy compound having a higher molecular weight include ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, hydroquinone, and pyrogallol.

Compounds obtained by esterification reaction using these raw materials include diethylene glycol diacrylate,
Polyethylene glycol diacrylate, 1,5-bentanediol diacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentanylthritol triacrylate, diethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, 1,3- Diacrylate and dimethacrylate compounds represented by butanediol dimethacrylate, polyvalent acrylates represented by tri, tetra, pentaacrylate or methacrylate of dipentaerythritol, tri, tetra, penta, hexaacrylate or methacrylate of sorbitol, etc. , polyvalent methacrylate compounds, oligomer ester acrylates, oligomer ester methacrylates, and epoxy acrylates and epoxy methacrylates synthesized by reacting epoxy resins with acrylic acid or methacrylic acid. In the above examples, a single polyfunctional unsaturated compound is used, but a mixture of two or more types can also be used. It is also possible to use monofunctional unsaturated compounds in combination.

Further, in the composition of the present invention, examples of photopolymerization initiators include acetophenone and its derivatives, benzophenone and its derivatives, Michler-Kent, benzyl and its derivatives, benzoin and its derivatives, thioxanthone and its derivatives,
Contains anthraquinone and its derivatives, α-aminoketone compounds represented by 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl-2-morpholino-1-propane-1, etc. It is something. These may be used alone or in combination as necessary. It is also possible to use an amine compound that sensitizes the action of the photopolymerization initiator.

Furthermore, the composition of the present invention contains an epoxy resin. Such epoxy resins have two or more epoxy groups per molecule on average, and are made by reacting bisphenols such as bisphenol A, bisphenol F, and halogenated bisphenol A with epichlorohydrin in the presence of a basic catalyst. Particularly preferred are bisphenol-type polyglycidyl ethers obtained by the above method, epoxy novolacs and epoxy cresols obtained by reacting novolac-type or cresol-type phenol resins with epichlorohydrin, and the like.

Furthermore, the composition of the present invention contains a predetermined curing agent for epoxy resin. The predetermined curing agent for epoxy resins is dicyandiamide and a diaminotriazine-modified imidazole compound that has latent curing properties for epoxy resins represented by the following general formula.

2N (R is an imidazole compound.) For example, 2,4-diamino-6(2'-methylimidazole-(1''))ethyl-s-triazine, 2,4-diamino-6(2'-ethyl- 42-Methylimidazole-triazine, 2,4-diamino-6(2'-undecylimidazole-(1'))ethyl-S-triazine or 2,4-diamino-6(2'methylimidazole-
(1')) Ethyl-S-triazine incyanuric acid adduct and the like.

Furthermore, the composition of the present invention comprises an ultraviolet absorber, an antifoaming agent, a filler, and a solvent. As such an ultraviolet absorber, a compound that absorbs light in a light wavelength region of 300 nm or more but is not related to the photocuring reaction of the resin composition can be used. Examples include 4-t-butyl-4'-methoxy-dibenzoylmethane, 2-ethylhexyl-P-
Methoxycinnamate, 2-(2'-hydroxy-3'
5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'tert-
Butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3'5'-t
art-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3-(3", 4"
, 5”, 6”-tetrahydrophthalimidomethyl)
-5''-methylphenyl)benzotriazole, etc. The ultraviolet absorber prevents hardening of the resist by UV light from the opposite side during simultaneous double-sided exposure, prevents so-called show-through, and prevents halation and increases resolution.

On the other hand, as such an antifoaming agent, an organic silicon compound containing a siloxane bond, typified by silicone oil, is mainly used. Furthermore, such a filler is preferably a fine quartz powder with a particle size of 10 μm or less. - Photocurable resins used for boat fishing have low mechanical properties and heat resistance of the photocured film. To achieve the objectives of the present invention, it is necessary to add a large amount of filler to significantly improve the above properties. However, since it is a photocurable resin,
The filler must not impede the transmission of ultraviolet light and inhibit photocuring. The quartz powder used as a filler transmits ultraviolet light or scatters it on its surface, so the photocuring reaction is not inhibited.

By using this filler, not only the above-mentioned properties are significantly improved, but also the plating elution resistance and plating reactivity resistance are improved.

Furthermore, the composition of the present invention contains an organic solvent for dissolving the diallyl phthalate prepolymer and epoxy resin. Such organic solvents include high boiling point solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, methyl calpitol, ethyl calpitol, butyl calpitol, and terpineol. preferable.

The photocurable diallyl phthalate resin composition of the present invention may contain other additives, for example, a thixotropic agent such as ultrafine quartz powder, if necessary.

A preferred blending ratio of the composition of the present invention is 4 to 30 parts by weight of the polyfunctional unsaturated compound per 100 parts by weight of diallylphthalate prepolymer.

0.5 to 12 parts by weight of a photopolymerization initiator, 3 to 35 parts by weight of an epoxy resin, 0.5 to 10 parts by weight of an antifoaming agent, and 55 to 100 parts by weight of a solvent for dissolving the diallyl phthalate prepolymer. , with a given epoxy hardener,
The blending ratio of dicyandiamide and diaminotriazine-modified imidazole compound is 1671 to 5/1, the amount of these mixtures added is 2 to 20 parts by weight per 100 parts by weight of the epoxy resin, and the ultraviolet absorber is further added in the range of 0.1 to 5/1. 10 parts by weight, preferably an amount that reduces the amount of ultraviolet light passing through the coating film of the diallyl phthalate resin composition to below o, ox, yci.

The amount of filler added is 20 to 100 parts by weight per 100 parts by weight of diallyl phthalate prepolymer.

More specifically, in the present invention, it is essential to strictly define the blending ratio of dicyandiamide and diaminotriazine-modified imidazole compound, and it is necessary that it be within the shaded range shown in FIG.

The upper and lower limits of this composition are the above-mentioned problem (a) of the present invention.
These items have been carefully selected so that all of the items from (j) to (j) can be satisfied at the same time.

Next, the second object of the present invention, which is a means for producing a printed circuit board by a part-reactive method using the above-mentioned photocurable diallyl phthalate resin composition as a plating-resistant reactive solder resist, will be described.

According to Fig. 1, holes are made in the copper-clad laminate by a method well known to those skilled in the art, and chemical copper plating catalyst nuclei are provided [Fig. 1, 2].
] Then, conductor circuits are formed on both sides of the substrate by etching the predetermined portions by a method well known to those skilled in the art [Fig. 1, 3).

Next, the photocurable diallyl phthalate resin composition of the present invention is applied to the entire surface of the substrate including the conductor circuit.

Next, the substrate coated with the resist is dried to solidify the resist. Solidified resist layers are formed on both sides of the substrate by repeating this method on the back side, or by simultaneously applying the photocurable diallyl phthalate resin composition on both sides of the substrate and then drying. The drying conditions are 60
At -100°C, the drying time is preferably 0.2 to 2 hours.

Next, a negative mask is closely attached to the resist on both sides, and UV light is irradiated and exposed from both sides at the same time.

The amount of irradiation is 0.1 to 1. J/d is preferred. Furthermore, even within this irradiation dose range, UV light incident on one side does not harden the resist on the other side at all.
This should be emphasized.

Next, the negative mask is peeled off from the resist surface, and the unexposed areas are developed. As a solvent suitable for such development, 1.1.1-
A nonflammable chlorinated solvent such as trichloroethane is used, and a developing time of 0.5 to 5 minutes is selected.

Next, the substrate is heated to harden the resist portion on which the pattern is formed. Curing conditions are 140-180'C.

0.2-2 hours is selected.

Next, the resist on the substrate is irradiated with UV light again to complete curing of the resist. The exposure amount suitable for the post-darkening exposure is 1 to IOJ/Ci.

Through the above steps, a resist layer is formed on the substrate [
Figure 1, 4) 9 Next, the board is immersed in chemical copper plating, and thick chemical net plating is applied only to the raw chestnut parts such as inside the through-hole and on the land, and then the part additive method is applied. The printed circuit board is manufactured (Fig. 1, 5). A particularly important advantage of the present invention is that there is no peeling of the resist on the circuit copper foil during galling copper plating.

In the above-described part additive printed circuit board manufacturing, the resist of the present invention can simultaneously satisfy all of the above-mentioned problems. For this reason, it has become possible to manufacture high-density printed boards using the parti-additive method.

〔Example〕

Examples 1 to 39 Hereinafter, the photocurable diallyl phthalate resin composition of the present invention and a method for manufacturing a printed circuit board using the same as a plating-resistant reactive solder resist will be specifically described. 1st
According to the diagram, holes are made in a glass epoxy double-sided mesh laminate covered with 35 μm copper foil using a method well known to those skilled in the art, and a catalyst that will serve as a plating core is applied [Fig. 1, 2]. A conductor circuit is formed on both sides of the board by etching a predetermined portion of the copper foil.

Next, the photocurable diallyl phthalate resin composition of the present invention (Tables 1 to 4, Examples 1 to 39) is applied to the entire surface of the substrate including the conductor circuit. The photocurable diallyl phthalate resin composition of Example 1 was produced by the following method. For example, the composition of Example 1 in Table 1 contains (a) 100 g of diallyl phthalate prepolymer (Daisodatsubu A: manufactured by Daiso Nihon Co., Ltd., average molecular weight 7,000), (b) 20 g of 1-rimethylolpropane trimethacrylate, ( C) Nipicote 828 (bisphenol A type epoxy resin: oil-based shell epoxy, K).

) 15g, (d)2-methyl-1-[4-(methyl)
16 g of phenyl-2-morpholino-1-propane,
(E) 2 g of 4.4' bis-(diethylamino)benzophenone, (H) 1.5 g of dicyandiamide, (G) 2
,4-diamino-6[21-methylimidazole-(1
')]] Ethyl-8-triazine 0.2 g (h) Ultraviolet absorber: 4-t-butyl-4'-methoxy-benzoylmethane 3 g, 2-ethylhexyl-P-methoxycinnamate 3 g, (h) quencher Foaming agent: silicone oil 5H-2
03 (manufactured by Toshi Silicone) 5g, (nu) solvent:
Ethyl cellosolve acetate 35g, butyl cellosolve acetate 33g, (l) Thixotropic agent (fine quartz powder Aerosil A380: manufactured by Nippon Aerosil) 3g, (e)
Weigh 50 g of filler (Glistalite 5X: manufactured by Tatsumori Nihon Co., Ltd. 9 particle size: 1 μm).

Put the above ingredients (a) to (e) and (nu) into a separable flask, mix and heat at 80 to 100°C for 30 minutes to 2 minutes.
Dissolve by heating for an hour. After returning these mixtures to room temperature, (
After adding the ingredients (F) to (S), (L), and (E) and stirring thoroughly, mix the mixture using a three-roll mill. Furthermore, the viscosity is adjusted by adding an organic solvent (N) to make it suitable for screen printing, roll coater application, etc.

Next, the substrate coated with the resist is dried at 80° C. for 30 minutes to solidify the resist. The same method is repeated on the back side to form a resist assimilation layer. Next, a negative mask is closely attached to the resist on both the front and back sides, and UV light is applied to both sides at the same time. Expose by irradiating with J/aj.

Next, the negative mask is peeled off from the resist surface, and the unexposed areas are removed by spray development using 1.1.1-trichloroethane as a developer at room temperature for 1 minute.

Next, the substrate is heated at 150° C. for 40 minutes to harden the patterned resist portion. Further, the resist on the substrate is irradiated with 5 J/ad of UV light as post-exposure to complete curing of the resist [FIG. 1, 4)]. Next, it is immersed in a chemical copper plating solution (manufactured by Silapray Co., Ltd.) having the composition shown below for 15 minutes to perform 4-layer chemical copper plating of about 0.4 μm.

Copper mix 328A... 125mQ Copper Copper mix L... 125mR Copper Copper mix C... 25mu distilled water ...Total amount as IQ After that, soak it in a chemical mesh plating solution with the following composition for 15 hours to prepare through holes. A printed circuit board is manufactured by applying chemical copper plating to a thickness of about 30 μm on necessary parts such as inside the holes, lands, and terminals [Fig. 1, 5
)Ko.

CuSO4・5H2o...12gEDTA・2N
a...42g Na0H (amount to adjust the pH of the plating solution to 12.3) Amine surfactant...0.1g αα'-dipyridyl...0.05 g37% formalin °5m12 KzS --0,001g
Distilled water The total amount is IQ Plating conditions: Liquid temperature 70℃ pH 12.5 hours 15 hours Deposition potential -0.6 to -〇, 9V The plating solution components in the plating tank are controlled by automatic management equipment and by-products. The attachment of the removing liquid regenerator was kept constant.

In the above printed circuit board manufacturing process, the chemical copper plating step in item 4 is performed after the resist film is formed, but it can also be performed before the resist film is formed. It also has the effect of blocking it from reaching the hall.

In Examples 1 to 39, including the above-mentioned photocurable diallyl phthalate resin composition, the influence of the blending amount of each component of the resin composition on the manufacturing process and product of printed circuit boards was investigated, and the results are shown in Table 1. Shown in .2. In particular, FIG. 3 shows the amount of the epoxy curing agent that affects the plating reactivity, which is one of the important characteristics in the present invention. The items examined and evaluation methods are as follows.

(1) Coatability: A coating film with no residual voids and a smooth surface was rated as good. (2) Adhesion exposure property: A negative mask was placed in close contact with the negative mask, and after exposure to UV light, no resist was adhered to the negative mask, which was evaluated as good.

(3) Developability: Perform spray development using 1.1.1-trichloroethane as a developer for 1 minute at room temperature, and the unexposed areas should be completely dissolved and the resist in the exposed areas should not swell. And so. (4) Anti-bleed-through: Thickness 1
．． A resist is applied to both sides of the glass epoxy laminate plate No. 6 to a thickness of about 40 μm and dried. A negative mask is brought into close contact with the resist, and UV light is irradiated from one side with IJ/ci, followed by development. If the resist on the back side was not hardened and there was no resist residue, it was considered good. (5) Plating elution resistance: Those that did not reduce the film properties (tensile strength, elongation) of chemical copper plating were rated as good. Specifically, a resist film of 400 d was applied per 1Ω of chemical copper plating solution. (6) Resistance to plating reactions (resistance to cathode peeling): After chemical mesh plating is applied to the resist coated on conductor circuits connected to through-holes, lands, terminals, etc. where chemical mesh plating is performed. , Those with no peeling or discoloration were considered good. (7) Electrical insulation: A comb-shaped pattern according to JIS-C-2519 is made on a copper-clad glass epoxy laminate, a resist film is formed on it, and after passing through the chemical copper and plating process described above, when moisture is absorbed insulation resistance is 1o
Those with a value of gΩ or more were considered good.

(8) Apply flux to the heat-resistant niblint circuit board,
Dip in a 280°C solder bath for 10 seconds and return to room temperature.

After repeating this process 10 times, the resist had no abnormality such as blistering or peeling, and was judged as good.

The preferred blending ratio constituting the present invention is 4 to 30 parts by weight of the polyfunctional unsaturated compound and 0.5 to 12 parts by weight of the photopolymerization initiator to 100 parts by weight of the diallyl phthalate prepolymer.
Parts by weight, 3 to 35 parts by weight of epoxy resin, 0.5 parts by weight of antifoaming agent
10 to 10 parts by weight, 55 to 100 parts by weight of an organic solvent, and a blending ratio of dicyandiamide and doaminotriazine-modified imidazole compound as an epoxy curing agent of 16/1 to 5.
/1, the amount of these mixtures added is 2 to 20 parts by weight per 100 parts by weight of the epoxy resin and 0.1 to 10 parts by weight of the ultraviolet absorber, all the properties necessary for manufacturing printed circuit boards can be achieved. I was satisfied at the same time.

Example 40 In order to optimize the printed circuit board manufacturing process related to the present invention, the photocurable diallyl ratate resin composition shown in Example 1 was used as a solder resist to examine the effects of each process condition on various characteristics. I considered it. Note that the process conditions other than the items to be examined were the same as in Example 1.

The resist of the present invention is in a liquid state and needs to be dried after application in order to be able to adhere to a negative mask. The optimum drying conditions were 60-100°C for 0.2-2 hours.

If dried at 50°C for 2 hours, the solvent will remain and contact exposure will not be possible. On the other hand, if the epoxy resin is dried at 110° C. for 2 hours, the epoxy resin will be thermally hardened, and pattern formation by development will not be possible. Next, the heat curing step is the most important because it involves curing of the epoxy resin, which affects plating resistance. The optimum curing conditions were 140-180°C for 0.2-2 hours. Curing at 130°C for 2 hours will result in incomplete curing of the epoxy resin, resulting in poor plating resistance, and curing at 190°C will oxidize the circuit copper foil, resulting in poor plating reactivity, making it unsuitable for practical use. Ta. Next, we considered post-exposure. Effective for increasing heat resistance, optimal conditions are 1-J, 0J
It was lcd.

JIS-C-5012 printed circuit boards manufactured using the composition range and process conditions of the photocurable diallyl phthalate compositions of Examples 1 to 39 as solder resists were used as solder resists.
The thermal cycle test was repeated 100 times, but no abnormalities such as blistering or peeling of the resist on the circuit network foil or cranking or blistering of the through-holes occurred.

Comparative Examples 1 to 26 Printed circuit boards were manufactured using the process conditions of Example 1 but outside the composition range of the photocurable diallyl phthalate compositions of Examples 1 to 39 as solder resists (Tables 5 to 7,
Comparative Examples 1 to 26). Coatability, close exposure, anti-bleed-through,
Since it was not possible to simultaneously satisfy developability, plating elution resistance, plating reactivity resistance (cathode peeling resistance), electrical insulation properties, and heat resistance, a printed circuit board that could be used for practical purposes could not be obtained.

The photocurable diallyl phthalate resin composition according to the present invention can be applied not only to printed circuit boards produced by a part-additive method, but also to printed circuit boards produced by a subtract method or a fully additive method.

(The following is a blank space) Table 7 [Effects of the Invention] As explained above, the photocurable diallyl phthalate resin composition of the present invention has coating properties, adhesion exposure properties, developability, plating elution resistance, plating reactivity ( It has excellent cathode peeling resistance), electrical properties, and heat resistance, and by satisfying these properties at the same time and making it possible to apply the part-reactive method to printed board manufacturing, we are able to create high-density printed circuit boards that can withstand practical use. It can be obtained using a simplified method.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the manufacturing sequence of a part-reactive printed board according to the present invention. FIG. 2 is a cross-sectional view showing the manufacturing order of a printed board by the subtract method. FIG. 3 shows an optimal first embodiment in which the photocurable diallyl phthalate resin composition of Example 1 is used, and the dicyandiamide and diaminotriazine-modified imidazole compounds simultaneously satisfy the characteristics necessary for manufacturing printed boards.

Claims (1)

[Claims] 1. Prepolymer of diallyl phthalate, polyfunctional unsaturated compound, photopolymerization initiator, epoxy resin, predetermined epoxy curing agent, ultraviolet absorber, antifoaming agent, filling coating properties, adhesion exposure properties, developability, show-through resistance, plating elution resistance, plating reactivity resistance, so-called cathode resistance. A photocurable diallyl phthalate resin composition that can be patterned by UV exposure and solvent development, and is suitable for solder resists with excellent removability, electrical insulation, and heat resistance. 2. The molecular weight of the diallyl phthalate prepolymer is 3,000 to 30,000, and the polyfunctional unsaturated compound is acrylate or methacrylate of a hydroxy compound, oligomer ester acrylate or methacrylate, epoxy acrylate or methacrylate. The photocurable diallyl phthalate resin composition according to claim 1, characterized in that the photocurable diallyl phthalate resin composition is at least one selected from among these. 3. The photocurable diallyl phthalate resin composition according to claim 1, wherein the epoxy curing agent is a mixture of dicyandiamide and a diaminotriazine-modified imidazole compound. 4. The blending ratio of the photocurable diallyl phthalate resin composition is 4 to 30 parts by weight of the polyfunctional unsaturated compound and 0.5 to 12 parts by weight of the photopolymerization initiator to 100 parts by weight of the diallyl phthalate prepolymer. 3 to 35 parts by weight of an epoxy resin, 0.5 to 10 parts by weight of an antifoaming agent, 20 to 100 parts by weight of a filler, and 55 to 100 parts of a solvent for dissolving the diallyl phthalate prepolymer and epoxy resin. Parts by weight, as a given epoxy curing agent,
The blending ratio of dicyandiamide and diaminotriazine-modified imidazole compound is 16/1 to 5/1 in parts by weight, and the amount of the mixture added is 2 to 20 parts by weight per 100 parts by weight of the epoxy resin, and the ultraviolet absorber is ,0
．． The photocurable diallyl phthalate resin composition according to claim 1, characterized in that the amount is 1 to 10 parts by weight. 5. A printed circuit board using the photocurable diallyl phthalate resin composition according to claim 1. 6. A printed circuit board manufacturing method comprising the following steps, using the photocurable diallyl phthalate resin composition according to claim 1 as a plating-resistant photo solder resist. A. Drill a hole in the copper-clad laminate and attach a chemical copper plating catalyst nucleus to the inner wall of the hole. b. Form a conductor circuit on the insulating substrate by etching. c. Form the conductor circuit and through-hole portion as necessary. d. Applying the photocurable diallyl phthalate resin composition according to claim 1 to the entire surface of the substrate, and e. After drying the photocurable diallyl phthalate resin composition, chemical copper plating is applied. Necessary hole inner wall (through hole) part, land part around it, connector part, and I
C. Irradiate ultraviolet rays to areas other than the connecting parts, f. Perform solvent development to remove uncured diallyl phthalate resin composition and form a pattern, g. Heat cure, h. Irradiate ultraviolet rays again if necessary, i. Apply chemical copper plating.