JPS61117885A - Manufacture of printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a printed circuit board, and more particularly to a method for manufacturing a printed circuit board that is excellent in mass production and in which through-holes are formed by chemical copper plating.

[Background of the invention]

Conventionally, printed circuit boards have been manufactured by etching the circuit pattern and forming through holes using chemical copper plating. This method is as shown in Japanese Patent Application Laid-Open No. 57-71199, and the manufacturing process is simple and a uniform thickness of steel plating can be formed, making it possible to easily manufacture high-density substrates. It is a characteristic.

However, in this method, in order to obtain a circuit board with high electrical insulation, an activator protective ink 5 as shown in FIG. 2 is formed on the resist layer 4 to prevent chemical copper plating from depositing on the resist film. There was a need. Therefore, the process of applying the activator protective ink and the process of removing the activator protective ink 5 after activation are an economical burden, and the positioning accuracy of the protective ink 5 is strictly required. It was not a manufacturing method suitable for circuit boards.

Also, special public service 44-19661 and special public service 5y-4N6
As shown in Figure 2, by adding properties that make it difficult for steel to precipitate to electrical insulating materials other than circuit parts, or by adding an inhibitor.
Methods of preventing adhesion of activated catalysts are also known. However, this method requires finding the optimal material, composition, and conditions for each printed board manufacturing method, and is not sufficient to prevent abnormal precipitation in chemical copper plating that involves surface defects. Ta.

In addition, as a method that does not use protective ink,
8065 K has been proposed. In this method, as shown in FIG. 3, the resist layer 4 is coated on the substrate activated by the catalyst 6, so the catalyst 6 remains between the circuits and tends to cause insulation deterioration. There was no way to manufacture it.

In addition, conventional resists lack adhesion to steel foil, so when immersed in a high temperature (7at) strong alkaline (pH 12) chemical copper plating solution for 10 to 20 hours, the resist peels off and the substrate It was difficult to ensure high reliability.

On the other hand, steel plating films obtained from conventional chemical copper plating solutions lacked sufficient mechanical properties such as strength and elongation. Therefore, the problem that the conductor of the through hole is likely to break due to thermal shock or repeated thermal stress when hanging the component is likely to occur.

As described above, with the conventional methods, mass production of highly reliable printed circuit boards is not sufficient, and it is difficult to obtain products with a high yield.

[Purpose of the invention]

An object of the present invention is to provide a method for manufacturing a printed circuit board which eliminates the above-mentioned drawbacks of the prior art, has excellent mass productivity, and has high reliability.

[Summary of the invention]

The above purpose is to activate the wiring board on which through-holes and circuit patterns are formed, cover the parts other than the through-holes and land portions with a plating-resistant resist, and perform plating. The plating resist can withstand high-temperature alkali, and this can be achieved by using a plating solution with good tensile strength and elongation.

! ! ! In detail, the following manufacturing method is used as an example. That is, as shown in FIG. 3, after drilling a through hole 3 in a steel laminate, the entire surface is covered with a catalyst 6.
Activate with. Next, a photosensitive etching resist film is laminated on the substrate by a conventional method, and lands and circuits 2 are formed on the substrate through the steps of exposure, development, and etching peeling. For pattern formation, a so-called tenting method is used in which the etching solution does not enter the holes. .

In this process, no catalyst remains between the circuits, and a circuit board with high dielectric strength can be easily produced.

On the other hand, as an etching resist, in addition to the above, there is a method in which a liquid photosensitive resist is used to coat the inside of the through hole thinly to protect the catalyst.

There is also a method of using an ordinary liquid etching resist and protecting the catalyst from falling off with an alkaline etching solution.

Next, a plating-resistant plating resist 4 that has excellent adhesion to the copper foil and does not peel off even when immersed in a high temperature (7Q°C) and strongly alkaline (pH 12) chemical copper plating solution for 10 to 20 hours is applied to all but the desired areas. I'm going to cover it.

This resist must withstand severe chemical copper plating conditions during the subsequent thick chemical copper plating process, and must also withstand solder immersion when used as a product. After conducting various studies on plating-resistant solder resists suitable for such purposes, the following epoxy resin composition was discovered and used.

The epoxy resin composition used in the present invention contains an at epoxide compound, (A) a diaminotriazine-modified imidazole compound, and (e) dicyandiamide. , Further, as necessary, (d) a filler, (-) a thixotropic agent, an ω antifoaming agent, (- an organic solvent, (A) a coloring agent, and (i) a phenol compound) are added.

The epoxide compound (a) used in the present invention is a compound having an average of 2 (one or more) epoxy groups per molecule, such as bisphenols, halogenated bisphenols, bisphenol F, bisphenol S, catechol, resorcinol, etc. Polyglycidyl ether or polyglycidyl ester obtained by reacting a polyhydric phenol such as or a polyhydric alcohol such as glycerin with epichlorohydrin in the presence of a basic catalyst, and a polyglycidyl ester obtained by combining a novolak type phenol resin with epichlorohydrin. These include epoxy novola, epoxidized polyolefin epoxidized by a peroxidation method, epoxidized polybutadiene, dicyclopentagenated oxide, or epoxidized vegetable oil.

The diaminotriazine-modified imidazole compound (A) used in the present invention is represented by the following general formula.

(However, R is an imidazole compound) For example, 2.4
-diamino-6(i-methylimidazole-(1))ethyl-8-triasif, 2,4-diamino-6(2
'-Ethyl-4-methylimidazole-(II))ethyl-8-)riazine, 2,4-diamino-6(2'-undecylimidazole-(1i+ethyl-8-)riazine, 2,4-diamino- Examples include 6(2'-methylimidazole(1))ethyl-8-)riazine incyanuric acid adduct. The preferred range of the amount added is 1 to 30 parts by weight per 100 parts by weight of the epoxide compound; less than 1 part by weight will have no effect, and if it exceeds 50 parts by weight, the resist film will soften and the plating solution will When immersed in water, the film swells and whitens, further reducing the heat resistance of the film and sometimes causing blistering during soldering.

The preferred range of addition amount of CI dicyandiamide (CI dicyandiamide) used in the present invention is 0.2 to 2.0 equivalents per 1 epoxy equivalent of the epoxide compound; less than 12 equivalents has no effect; If this value is exceeded, dicyandiamide will be eluted from the resist film when it is immersed in a plating solution, and the chemical plating reaction will stop, making it impossible to put it to practical use.

The above (dl) filler used in the present invention includes fine inorganic powders such as talc, mica, alumina, barium sulfate, 8i02, TiO2, etc. 3 to 4 for
It is preferable to add 0.00 parts by weight. If more than 40 parts by weight is added, the ability to form a coating will be poor, and if less than 5 parts by weight, no improvement in properties can be expected. The particle size of the filler is 1
A thickness of 0 μm or less is desirable. The filler serves to improve the printability of the solder resist ink and to improve the mechanical properties of the film.

The thixotropic agent (-) in the present invention is used to improve the printability of the resist ink. As a thixotropic agent,
Si 02 , At20. Particle size α1 of inorganic materials such as
The thixotropic index of resist ink with good printability [(viscosity measured at a rotation speed of 1 rpm with a B-o viscometer)/(speed of rotation of 1 rpm) is obtained by appropriately adding ultrafine powder of µm or less.
(viscosity measured by )] 5 to 40.

The antifoaming agent of ω in the present invention is effective in removing air bubbles that are entrained during printing, and is effective for removing air bubbles that are entrained during printing. α2~8]i
It is used by adding a certain amount.

As the above-mentioned (fl) organic solvent in the present invention, it is easy to use those with low volatility and a boiling point of about 100 or more. For example, i-butyl alcohol, methyl isobutyl calpitol, cyclohexanol, leupropylacetate, leupropylacetate, etc. , i-butyl acetate, 5a
c-butyl acetate, amyl acetate, methyl amyl acetate, ethyl lactate, butyl lactate,
Methyloxytol acetate, oxytol acetate, butyloxytol acetate, methyloxytol, oxytol, butyloxytol, methyldioxytol, dioxytol, butyldioxytol, methyl-lupropyl ketone, methyl-louptyl ketone/
, methyl-1zo-butyl ketone, diisobutyl ketone, cyclohexanone, infinalone diacetate alcohol, nitromethane, nidoethane, ethylene glycol mobutyl ether, diethylene glycol monobutyl ether, and the like. Considering the printability of the resist ink, the viscosity of the ink should be adjusted to 800 to 10,000 poise (20 υ
Add an amount of organic solvent that can be measured using a B-type rotational viscometer (1 rpm).

If further coloring is desired, pigments such as phthalocyanine blue and phthalocyanine green are used as the colorant (A).

In addition, in order to reduce changes in viscosity properties over time during storage of the plating-resistant solder resist, a trace amount of a phenolic compound (i) such as pyrogallol or hydroquinone is added to the solder resist.

The above epoxy resin compositions, so-called resist ink components (a), (c), (el, (f), (14, (A
), (i), etc. are kneaded in a rice miller, kneaded in a three-arc mill, and an organic solvent is added as necessary to adjust the viscosity and thixotropy index.

The above composition can be printed and applied onto a substrate by a general screen printing method. The Soviet version of this is
The desired plating solution resistance and solder heat resistance can be ensured.

Next, the resist-coated board is immersed in a specified chemical copper plating solution, and through-holes are bonded using chemical copper plating (7).
form. Before this factory, to prevent the activated catalyst from falling off, a Rochelle salt type room temperature plating bath was used to coat it thinly (
It is also economically preferable to plate the steel. An example of such a plating solution is a three-liquid hot-temperature chemical copper plating, Caparacid 528 A, C, and L manufactured by Shiraplay Co., Ltd. The thickness of the tip is 2 for chemical copper plating.
It is necessary to continuously deposit metallic steel of about 0 to 55 μm. In order to ensure sufficient connection reliability for through-hole steel, we have extensively investigated a chemical copper plating solution that has excellent mechanical properties of the plating film and has a long service life and is less likely to cause abnormal copper precipitation.As a result, we have developed the following results. The characteristics of the chemical copper plating solution used in the present invention for the above purpose are: a complexing agent for steel (1) ions and copper (II) ions;
A reducing agent for copper (I) ions, an alkali metal hydroxide, a polyoxyethylene surfactant, a complexing agent for steel (1) ions, an inorganic compound of a group 4B element, or an inorganic compound and a cationic surface active agent. It consists of an agent. Even if industrial chemicals are used, the strength and elongation of metal steel precipitated by chemical copper plating can be significantly improved, and properties of 50 (/- or more, 3% or more) can always be stably obtained, and abnormal precipitation of steel can be prevented. It's hard to get up.

Here, the two-tone ions are supplied from water-soluble copper salts represented by sulfuric acid steel, formic acid steel, chloride steel, etc. Sulfuric acid steel is mainly used for economic reasons. Complexing agents for two-tone ions are commonly used to prevent precipitation of two-tone ions in alkaline aqueous solutions, such as ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, iminodiacetic acid, Polyaminocarboxylic acids typified by iminodiacetic acid nitrilotriacetic acid and their alkali metal salts are used, but the sodium salt of EI)TA is used mainly for economic reasons. The reducing agent reduces the complexed two-tone ions to metal steel, and uses formaldehyde or formaldehyde aqueous solution formalin, formaldehyde polymers represented by paraformaldehyde, borohydride compounds, hydrazine, etc. Formalin is also used for economic reasons. pH
lll moderation agent is used to maintain the pH of the liquid at an appropriate value.
If the hydroxide is an alkali metal, sodium hydroxide, which is inexpensive, is commonly used. On the other hand, the complexing agent of the 1st ion dissolves the oxidized No. 1 steel, which is a by-product in the metallurgy.

The inventors focused on the effects of polyoxyethylene surfactants, cationic surfactants, and compounds of Group 4B elements, and extensively searched for liquid compositions that would yield high-strength plating films within easily controllable concentration ranges. . As a result, a chemical copper plating solution is used that contains compounds of Group 4B elements such as silicon, germanium, tin, and lead among the elements that become oxygen acid ions in an alkaline plating solution, and a polyoxyethylene surfactant. It has been found that the object of the present invention can be achieved by this.

Such polyoxyethylene surfactants include (1) polyoxyethylene HO÷CH, CH, O÷, H (2) alkyl ester type polyoxyethylene 几-CO
O÷CH, CH, 0+, H (3) Alkyl ether polyoxyethylene R-0÷
CH, CH, 0-), H (4) Alkyl allyl ether polyoxyethylene (5) Alkylamine polyoxyethylene (6) Polyoxyethylene, polyoxypropylene copolymer
Gate・HO÷CH2CH,0zeCHcCH20seCH2CH,O
÷H = alkyl group, π:÷CH2CH2O÷, H or H, etc.

Further, as the cationic surfactant, primary, secondary, or quaternary alkyl amine salts or quaternary ammonium salts, ester- or ether- or amide-bonded amines, pyridinium salts, and the like can be used. Preferably, a quaternary alkaline amine salt that is stable without being decomposed in an alkaline aqueous solution, specifically (C+aHssNCCHs')s
] Br.

(C+6H□N (CHi )z CHz C5H6)
Preference is given to using CL.

The 4B group element compound added to such chemical copper plating solution is
It is a compound of silicon, germanium, tin, and lead that produces oxygen acid ions when dissolved in an alkaline plating solution. Examples of silicon compounds include alkali metal salts of orthosilicic acid and metasilicic acid that generate silicate ions in the polishing solution, as well as simple silicon, silicon oxide, silicon hydride, silicate minerals, and amorphous silicate compounds. It can be mentioned as a representative. Compounds containing germanium include simple germanium, germanium oxide, germanium hydride, and kermanate salts. As a compound containing tin.

Examples include simple tin, alkali metal salts of stannic acid, tin oxide, and sulfuric acid. Compounds containing lead include basic lead carbonate,
These include lead halides and lead sulfate.

When the above-mentioned Group 4B element compounds are added to a chemical copper plating solution, the elements turn into oxygen acid ions such as silicate ions and germanate ions in the plating solution. Although the influence of such oxyacid ions on the copper precipitation reaction has not been completely clarified, it is presumed that it is mainly due to the adsorption effect of the ions on the plating reaction surface. The chemical copper plating solution also contains a surfactant that has an adsorption effect.

Therefore, since adsorption of the ion and the surfactant compete with each other on the reaction side, the adsorption characteristics of the surfactant and the adsorption characteristics of the ion must be appropriately controlled. This is why the chemical copper plating solution of the present invention has a practical concentration of the 4B group compound and is therefore easy to manage.

If a surfactant with weak adsorption power to the reaction surface is used, priority will be given to the adsorption of group 4B elements.

Therefore, in order to obtain a steel coating with excellent properties, the concentration of the 4B group element must be kept at a very small amount.

If a surfactant with too strong adsorption power to the reaction surface is used, the adsorption of group 4B elements will be inhibited, so a large amount can be added. Therefore, the problem of liquid management is eliminated, but
Because the solution contains an excessive amount of adsorbed substance, the plating reaction may stop. Among the polyoxyethylene surfactants used in the present invention, alkylamine-based polyoxyethylene is particularly easy to handle and is favorable.

Alkylamine-based polyoxyethylene surfactants have amino groups (positively charged) in their molecules, so they have the properties of both nonionic and cationic surfactants that selectively adsorb to metals. . Therefore, it is presumed that the adsorption force to the reaction surface is appropriate. Only when such a surfactant is used will the appropriate concentration range of the Group 4B element be a practical and easily manageable concentration. 4B discovered experimentally
The appropriate concentration range for group elements is approximately 5
~50 mmol/L. This value depends on the difference in the atomic weight of group 4B elements, and when using silicon compounds, S
This corresponds to about 84 to B4O11f/lK. When a germanium compound is used, G- is about α22~
2.2? /L tin compound is about α56~16 as 8n
f/l, approximately Q as Ph for lead compounds, 62 to 6.2f
/l.

As described above, in addition to a polyoxyethylene surfactant and a group 4B element compound, the present invention uses αα'α diirisyl, 0-
7 enanthroline or derivatives thereof, etc. are added. All of these are complexing agents for steel (1) ions, and have the effect of stabilizing the plating rate and preventing liquid decomposition.

In the present invention, the liquid composition as described above is used.

A plating film strength of 50-/- or more and elongation of 3% or more can always be stably obtained without fear of contamination with external impurities.

On the other hand, abnormal precipitation (
As a result of various studies on preventing the precipitation of steel on unnecessary parts, we found that the above-mentioned chemical copper plating solution was significantly effective. The mechanism is estimated as follows. That is, in chemical copper plating, the following two reactions proceed simultaneously on the surface of a metal having a self-synthesizing effect, such as steel, so that steel is successively deposited.

Cμ”-L+2e-→Cμ+L ・・・River・・・・・・
・・kawa・dan・(II)HCHO+ 20) r -e
HCOO″+H20+ '/2H2+ e-”・”・
(Equation 21 (1) is a reduction reaction of steel (I) ions, where L represents a complexing agent that stabilizes copper (II) ions in an alkaline aqueous solution, and gDTA etc. are generally used. ( Equation 2) is an oxidation reaction of formaldehyde, and the fact that this reaction occurs on steel or a suitable metal with a catalytic action is the driving force for reduction of copper (II) ions.

In actual chemical copper plating, when the reaction of formula (1) occurs,
A side reaction occurs in which copper (I) ions, which serve as intermediates, diffuse into the plating solution from the precipitation reaction surface and move out of the system. The behavior of such intermediates has been specified to be responsible for anomalous precipitation on insulating materials, i.e. (il, (2
) In the plating solution near the steel surface where the reaction of the formula
0 fine particles are produced, which become the nucleus of plating and lead to abnormal precipitation. If the surface of the insulator other than the circuit portion is rough or has minute scratches, it is presumed that the plating core particles will easily adhere and steel will precipitate.

From the mechanism of the abnormal precipitation reaction as described above, it is most preferable to inactivate the plated core fine particles in order to prevent abnormal precipitation. In other words, it is sufficient to stop the reaction (2) of formaldehyde on the plating core, but from this point of view, various additives were investigated, and the specific surfactant and group 4B inorganic compound mentioned above were investigated. It has been found that when used in combination, it is effective in preventing abnormal copper precipitation.

The chemical copper plating solution described above is used in the present invention, and the preferred composition range is as follows, by way of example.

1. Main component of chemical copper plating solution CI&804・5H205~551/1iTA2Nα
15-2001/lNαOHpH 11.
5-13.0 amount 57% E/L/ff phosphorus 2-10
11I4/l Veggie Viridyl 5~1oowV
/z Polyoxyethylene surfactant 10q/L ~ Solubility limit 2 Additives having the effects of the present invention (the following people or a combination of A and B) A, Group 4B element compound (as an element) 5 to 30 mmol/lB, Cationic Surfactant 20 q/l ~ Solubility Limit [Examples of the Invention] The method for manufacturing a printed circuit board of the present invention will be further explained below using specific examples.

Example 1 As shown in FIG. 1 (α), a through hole 3 is drilled in a glass epoxy double-sided steel clad laminate 1 coated with copper foil 2 of a 35μ door as shown in FIG. The activated catalyst 6 was applied by immersing it in a Pd catalyst solution.Next, as shown in FIG. Lands and circuits 2 were formed on the substrate by a tenting method consisting of steps, and were shaped like a mountain as shown in FIG.

Next, as a pre-treatment for printing the solder resist, the substrate is
After immersing the substrate in an aqueous N-hydrochloric acid solution for 50 seconds, the entire surface of the substrate was buffed, washed with water, and dried. On this board, a metallization-resistant solder resist with the following composition was printed by screen printing, and in order to prevent the solder resist from bleeding during the heat curing process, it was irradiated with ultraviolet rays for a short time using a mercury lamp, and then heated in a heating furnace for 13 hours.
After curing for 0 tl+50 minutes, a plating-resistant resist layer 4 was formed as shown in FIG. 1 (ml).

The above plating-resistant resist is an epoxide compound,
100 parts by weight of Epicoat 152 (KJ!! novolak type epoxy resin, epoxy equivalent weight 175, manufactured by Shell Chemical Co., Ltd.),
2.4-diamino-6(2゛-methylimidazole-(
1 part of ethyl-8-triazine, 8 parts by weight of dicyandiamide, Merck powder L-1 (as a filler)
Made in Nippon Talc, average particle diameter 2 μrn) 10 parts by weight,
As a thixotropic material, 5 parts by weight of ultrafine silicone powder Aerosil 200 (manufactured by Nippon Aerosil Co., Ltd.), and 2 parts by weight of ultrafine alumina powder Aerosil C (manufactured by Nippon Aerosil Co., Ltd.),
2 parts by weight of silicone oil 8C-5540 (manufactured by Toshi Silicone Co., Ltd.) as an antifoaming agent, 1.5 parts by weight of phthalocyanine green as a coloring agent, and 12 parts by weight of ethylene glycol monobutyl ether as an organic solvent. It was obtained by thoroughly kneading it using
Next, a chemical copper plating solution with the following composition (manufactured by Siriplay) was applied.
The sample was immersed in the liquid for 2 minutes, and chemical copper plating was applied to a thin layer of about 1 liter and 14 μm.

Copper mix 328 A 125m Copper mix 328L 125m Copper mix 328 C25tIIt Distilled water Amount to bring the total volume to 16 After that, thicken with chemical copper plating as shown in Figure 5 (0) [
A through-hole chemical copper plating layer 7 was formed. The composition of the chemical copper plating solution, plating conditions, and mechanical properties of the plating film at this time are as shown below.

Composition = Cμ804-5H20122 EDTA・2Nα 42? NaOH12F Polyethylene glycol stearylamine 0.1f α,α-dipyridyl 5Wq 67 Thiformin 5- Nα2SCO,・9H,OIF Distilled water Quantity to make the total amount 1 t Conditions: Plating solution temperature 70υpH12, 3 hours 15 hours Plating speed Approx. 2. 0 μm Mechanical properties of plating film Strength 5411.4 Elongation at break 6 The components of the plating solution in the plating tank were kept constant through automatic management. The iron and substrate were taken out from the plating solution, washed with water, and then dried in a heating oven at 120 for 20 minutes.

The adhesion between the resist coating film of the printed circuit board thus manufactured and the circuit steel foil was evaluated by a cross-cut cellophane tape test, and it was found that the resist film did not peel off and had good adhesion. Furthermore, even when immersed in a 260 t solder bath for 20 seconds, there was no deterioration such as blistering or peeling of the resist film, and it was found that it had good solder heat resistance.

In addition, as a result of observing the through-ball portion and land portion immediately after plating, it was found that the thick copper precipitated evenly and unevenly, and no abnormal precipitation of steel was observed on the resist other than the desired portions.Furthermore, The above substrate was prototyped by repeating the plating process 10 times with a plating load of 1 dnt/, but no abnormal copper precipitation was observed.

Further, the board was subjected to the JI8-05012 thermal cycle test 100 times, but no abnormality such as cracks or bulges occurred in the steel of the through-hole portion. Also, 60
℃? As a result of measuring the insulation resistance between the circuits after leaving them in a constant temperature and humidity chamber at 5% RH for one week, no extreme insulation deterioration was observed.Example 2 Glass epoxy double-sided steel clad laminate IK covered with steel foil 2, as shown in the first hardening), drill a through hole 3, 8'/1'! d The activated catalyst 6 was applied by immersing it in a catalyst solution. Next, $1 figure <c
A dry film 8 is laminated on the substrate shown in Figure 5, and a land and a circuit 2 are formed on the substrate by a tenting method consisting of exposure, development, etching, and peeling.
Then, as a pre-treatment for printing the solder resist, the substrate was
After immersing the substrate in an aqueous N-hydrochloric acid solution for 30 seconds, the entire surface of the substrate was buffed, washed with water, and dried. A plating-resistant solder resist having the following composition was applied to this substrate by screen printing, and was cured for 30 minutes at 130 °C in a heating furnace to form a plating-resistant resist layer 4 as shown in Figure 1 (cl). The above plating-resistant solder resist is made of epoxide compound such as Epikote 807 (Shell Chemical Co., Ltd., II.
, bisphenol F type epoxy resin, epoxy equivalent weight 17
0) 10 parts by weight, 2,4-diamino-6 (2゛-
Methylimidazole (1)) 2.5 parts by weight of ethyl-8-triazine, 7 parts by weight of dicyandiamide, 0.5 parts by weight of pyrogallol, quartz powder VXX as a filler (manufactured by Tatsumori, average particle size 1 μm) 20 parts by weight, ultrafine quartz powder Aerosil RY-2 surface-treated as a thixotropic material
5 parts by weight of silicone oil 5C-5540 (manufactured by Toshi Silicone) as an antifoaming agent, 1.5 parts by weight of phthalocyanine green as a coloring agent, A solvent-free, liquid-type solder resist ink composition was thoroughly kneaded using a machine and three rolls, and had a thixotropic index of 22° and a viscosity of 5520 poise (25, 1 rpm).

Next, a chemical copper plating solution with the following composition (manufactured by Shivgray) was applied.
The sample was immersed in the liquid, and a thin layer of about 0.4 μm was chemically plated with copper.

Thereafter, as shown in FIG. 3, a thick chemical copper plating was applied to form a through-hole chemical copper plating layer 7. The composition of the chemical copper plating solution, plating conditions, and mechanical properties of the plated film are as follows.

Composition: CtbSO,・5H2012fBDTA・2N
α 42 fNαOH12f Polyethylene glycol stearylamine α1 ? Hexadecyltrimethylammonium bromide CC1
4H! ! N (CHs) i 'l Bτo, osr Po α-dipyridyl 2 w9 57% formalin 5rnt Gg02 α3F Distilled water Amount to make the total amount 1 t Conditions: Placing solution temperature 70'c pH 12.5 hours 15 hours Placing speed approx. 2.0 μm Mechanical properties of plating film Strength: 50 to 55 elongation at break: 3 to 6% The components of the plating solution in the plating tank were kept constant through automatic management. Thereafter, the substrate was taken out from the plating solution, washed with water, and then dried in a heating oven at 120° C. for 20 minutes.

The adhesion between the resist coating film of the circuit board manufactured in this way and the circuit steel foil was evaluated by a cross-cut cello bump test, and it was found that the resist film did not peel off and had good adhesion. Ta. 2 more in a soldering bath at 260℃
It was also found that even after immersion for 0 seconds, there was no deterioration such as blistering or peeling of the resist film, and it had good soldering heat resistance.

Furthermore, as a result of observing the through-hole portions and land portions immediately after plating, it was found that thick steel was deposited uniformly, and no abnormal precipitation of steel was observed on the resist other than the desired portions. Furthermore, the above board was prototyped by repeating the plating load 1dsn7t 10 times, but the plating film had a strength of 50-/-
As described above, an elongation of 5- or more was ensured, and no abnormal precipitation of steel was observed.

Furthermore, the circuit board was subjected to a JIS-C5012 cooling and heating cycle test 100 times, but no abnormalities such as roughening or blistering of the steel in the through-hole portions occurred. Also, 60
As a result of measuring the insulation resistance between the circuits after being left in a constant temperature and humidity chamber at υ95% H for one week, no extreme insulation deterioration was observed.

〔Effect of the invention〕

From the above results, it is clear that the manufacturing method of the present invention can stably manufacture printed circuit boards with excellent heat resistance, electrical insulation, and reliability. In order to obtain these effects using conventional manufacturing methods, a large amount of cost is required for manufacturing equipment, quality control, process control, etc. Therefore, the present invention is economical and achieves the above effects using equipment that is not much different from conventional manufacturing methods. The effects are immeasurable.

[Brief explanation of drawings]

1, 2, and 5 are process diagrams of a printed circuit board manufacturing method. 1...Glass epoxy double-sided steel clad laminate 2...Steel foil 2...Circuit and land 5...Through hole 4...Resist layer 5...Activator protective ink 6...Catalyst 7...Through hole steel plating 8...Dry film

Claims (1)

[Claims] 1. Activating a copper-clad laminate with through holes formed in predetermined positions; forming a circuit by etching while protecting the activated catalyst in the through holes; 1. A method for manufacturing a printed circuit board, comprising the steps of coating with a predetermined plating-resistant resist, and depositing copper on through holes and desired areas with a predetermined chemical copper plating solution. 2. The plating-resistant resist in claim 1,
A method for producing a printed circuit board comprising an epoxide compound, a diaminotriazine-modified imidazole compound, and dicyandiamide. 3. The chemical copper plating solution in claim 1 contains copper (II) ions, copper (II) ion complexing agents, copper (II) ion reducing agents, alkali metal hydroxides, copper (I ) A method for manufacturing a printed circuit board, comprising an ionic complexing agent, a polyoxyethylene surfactant, and an inorganic compound of a group 4B element. 4. The chemical copper plating solution in claim 1 contains copper (II) ions, copper (II) ion complexing agents, copper (II) ion reducing agents, alkali metal hydroxides, copper (I ) A method for manufacturing a printed circuit board, comprising an ionic complexing agent, a polyoxyethylene surfactant, a cationic surfactant, and an inorganic compound of a group 4B element. 5. A method for manufacturing a printed circuit board, characterized in that the inorganic compound of Group 4B elements according to claims 3 and 4 is silicon oxide, germanium oxide, or an alkali metal salt of silicic acid.