JPS62279691A - Activation energy beam cured type solder and plating maskingagent - 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 3. Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to an active energy ray-curable solder and a plating masking agent (hereinafter referred to as masking agent). More specifically, it relates to active energy ray-curable masking agents that are screen printable and peelable.
Rubber latexes, thermosetting resins, or those whose main components are cellulose resins have been used.

[Problem to be solved by the invention]

Conventional peel-off and solvent-cleaning mask agents both require manual application to the required areas and require high temperatures and long periods of time for drying and curing, making it difficult to streamline the soldering and plating process. It has become an obstacle.

In addition, tapes in particular cannot be screen printed, so they have the disadvantage of not being able to be applied to fine patterns on printed circuit boards. Furthermore, tapes have a major drawback in that adhesive residue remains on the printed circuit board and deteriorates the electrical characteristics of the printed circuit board.Also, solvent cleaning types require long cleaning to avoid cleaning defects. There is a drawback that there is.

[Means to solve the problem]

The present inventors have conducted repeated research to improve these drawbacks, and as a result, they have arrived at the present invention. That is, the present invention provides an active energy ray-curable diene oligomer having at least one acryloyl group or methacryloyl group in the molecule; 10 to 80 parts by weight.

Monomer having ethylenically unsaturated group; 20 to 90 parts by weight Photoinitiator; 0 to 15 parts by weight Plasticizer; 0 to 80
Spread meter yield value 80-86QQ dyne/ad consisting of parts by weight and thickener: 0.1-16 parts by weight
The active energy ray-curable diene oligomer (hereinafter abbreviated as diene oligomer) having at least one ethylenically unsaturated group in the molecule used in the present invention is a solder and plating mask agent. There are (meth)acrylate modified products of diene oligomers.

Examples of methods for modifying diene oligomers with (meth)acrylates include the following methods.

Ato. A compound obtained by reacting a hydroxyl group-containing mono(meth)acrylate such as chiraethyl(meth)acrylate with an organic diisocyanate or an oligourethane containing two isocyanate groups so that one isocyanate group remains in the molecule; Oligobutadiene having at least one hydroxyl group in the molecule (e.g., 1,4-cis bond,
A product obtained by stoichiometrically reacting a 1.4-1-lance bond or a 1.2-vinyl bond, or an oligobutadiene derivative consisting of a mixed bond. (For example, Po1y bd-45A
After adding maleic anhydride to Cbon (Idemitsu Petrochemical ■), TE-2000 (Nippon Soda ■), Michelon uV°Bu-A (early use rubber ■), or Oly-17" urethane, hydrochloride Ester-modified with hydroxyl group-containing mono(meth)acrylate such as diethyl(meth)acrylate. (For example, embryo AO-1000-80,
MM-1ooo-go (Nippon Petrochemical ■), Finnbeam 101 (Nippon Seon ■)), or after epoxidizing a part of the double bond in oligobutadiene, containing carboxyl groups such as (meth)acrylic acid. things (meta)
Examples include ester-modified acrylates. In addition, in the above method, oligoisoprene or oligochloroprene may be used instead of oligobutadiene.The weight average molecular weight of these is 500 to too, ooo,
Preferably, it is 700 to 50,000. molecular weight is 5
If it is less than 00, the tensile strength will be low, and IQo, 0
00 is not preferable for dogs because it has poorer curing properties with active energy rays.

Note that the structure of the diene oligomer may be either cis or trans, and each may be contained in the same molecule.

In the present invention, among the monomers having an ethylenically unsaturated group (hereinafter abbreviated as monomers), mono(meth)acrylic 1
The /- group includes methyl alcohol.

Ethyl alcohol, propyl alcohol, n-butyl alcohol, fso-butyl alcohol-A/, ter
t-Butyl alcohol-/I/, neopentyl glycol.

Hexyl alcohol/L/l heptyl alcohol, octyl alcohol/l/, 2-ethylhexyl alcohol/I/
.

lauryl alcohol, tetradecyl alcohol.

Hexadecyl alcohol, 2-hydroxyethyl alcohol/l/, nonylphenol, cyclohexyl alcohol, tetrahydrofurfuryl alcohol/1/.

(meth)acrylic acid esters derived from monohydric alcohols such as dicyclopentyl alcohol, glycidol, and benzyl alcohol; and (meth)acrylic acid esters derived from ethylene oxide, ethylene oxide, and propylene oxide adducts of these monohydric alcohols. Acrylic acid ester;
As poly(meth)acrylates, 1,8-butanediol.

1.4-butanedio-/l/11.5-bentanediol.

Neopentyl glyco-/L'e1.6- to 1+? (meth)acrylates derived from polyhydric alcohols such as diol, diethylene glycol, triethylene glycol, polyethylene glycol, tripropylene glycol, trimethylolpropane, pentaerynurritol, dipentaerythritol, tetramethylolmethane, and binuphenol A; L/acid x nutyl; and poly(meth)acrylic acid esters derived from ethylene oxide or propylene oxide adducts of these polyhydric alcohols; other styrene, divinylstyrene, N
Examples include vinyl compounds such as -vinyl-2-pyrrolidone, vinyltoluene, and vinyl acetate; and allyl compounds such as diallylphthalate.

Among these, a rubber-like cured film can be obtained.

Preferred in terms of curability and compatibility with diene oligomers are mono(meth)acrylates such as 2-ethylhexyl acrylate, nonylphenol acrylate, tetrahydrofurfuryl acrylate, and glycidyl methacrylate.

These are glycol-based di(meth)acrylates and vinyl compounds such as divinylstyrene+N-2yl-2-pyrrolidone.

These monomers can be used alone or in combination of two or more.

Plasticizers used in the present invention include phthalate esters such as dimethyl phthalate, dibutyl phthalate, and dibutyl phthalate; fatty acid (dibasic) enethers such as dibutyl adipate, dioctyl adipate, and dibutyl sebacate; and chrycerol. Glycerin esters such as acetate; maleic acid esters such as diethyl maleate and dioctyl maleate; fumaric acid esters such as dibutyl fumarate; adipine fi-
Polyesters such as 1,8-butylene glycol;
Epoxidized esters such as epoxidized soybean oil; chic acid esters such as tris-β-carboxyethyl isocyanurate: g') octyl trimellitate;
trimellitic acids such as nonyl trimellitate; orthophosphoric acids such as trimethyl phosphate, trioctyl phonufate, triphenyl phosphate, trilauryl phonufate; phosphites such as triphenyl phosphite, nidibutyl and butyl Honufonic acid esters such as phosphonates; acidic phosphoric acid esters such as methylacidophonufate, octylacidhonufate, dibutylhonufate; cellulone esters such as cellulone acetate phthalate: tetramethyl silicate; Silicic acid esthetics such as;
He: / C: / :x Amides such as sulfonic acid butylamide; 2-ethylhexyl acetate, etc.

Among these, preferable ones are phthalate esters/fatty acid (dibasic) ethers and orthophosphate esters in terms of imparting flexibility and mold release properties to the cured film and having compatibility with other components. It is a kind. These plasticizers may be used alone or in combination.
More than one species can be used together.

The thickener used in the present invention includes oxidized wax;
Polyvinylpyrrolidone; amides such as ethylene bisstearylamide dialkyl-substituted amide (e.g. Dehyzo/I/ from Henkel Hakusuisha); benzylidene sorbitol such as monobenzylidene sorbitol, dibenzylidene sorbitol, tribenzylidene sorbitol (e.g. Shin Nippon Rika Co., Ltd.); Company's Gelol D); Hydrogenated castor oil: Metal soaps (e.g. aluminum stearate); Magnesium silicate, aluminum silicate, fine particle anhydrous silica, fine particle hydrated silica, bentonite, mica powder - calcium carbonate, titanium oxide, etc. Examples include inorganic thickeners. Among these, polyvinylpyrrolidone, benzylidene sorbitol, magnesium silicate, and aluminum silicate are preferred in terms of the flow characteristics of the masking agent.

Hydrous or anhydrous fine particle silica.

As the photopolymerization initiator used in the present invention, p-ter
t-Butyltrichloroacetophenone, 2.2-jethoxyacetophenone, benzyl dimethyl ket-/L/
(For example, Ciba Geigy's lrgacure 6st
).

Acetophenones such as 2-hydroxy-2-methylpropiophenone (e.g. Darocur 1173 from Merck & Co.), 1-hydroxycyclohexylphenylketone (e.g. Irgacure 184 from Ciba Geigy); hensifhenone, Michler's ketone, O-benzoyl- Benzophenones such as methyl benzoate: Penzoin alkyl ethers such as isopropylbenzoin ether: 2-chlorothioxanthone, 2
-thioxanthone such as methylthioxanthone; benzyl: 2-ethylanthraquinone; methylbenzoyl formate (e.g. VLCuRE5δ from Stouffer Chemical Company) diacetyl; tetramethylthiuram monosulfide; azo compounds such as allyl diazonium salt, etc. . These photopolymerization initiators can be used alone or in combination of two or more.

Furthermore, in order to enhance the effect of the photopolymerization initiator, a sensitizer can also be used in combination. As a sensitizer, aliphatic amines such as triethylamine, triethanolamine, and N-dimethyljetanolamine; aromatic amines; nitrogen heterocyclic compounds such as piperidine: 0-t! Ureas such as J-ruthiourea; Sulfur compounds such as sodium diethyldithiophosphate, soluble salts of aromatic sulfinic acids: N,N-disubstituted-p- such as N,N-dimethyl-p-aminobenzonitrile Examples include aminobenzonitrile compounds, phosphorus compounds such as nitri-n-butylphosphine, and sodium diethylthiophosphate; N-nitrosohydroquine derivatives; oxazoline compounds; chlorine compounds such as carbon tetrachloride and hexachloroethane. .

In addition, in order to improve storage stability, quaternary ammonium chloride; diethyl hydroxyamine; cyclic amide; nitrile compound; urea derivative; benzothiazole; hydroquinone; hydroquinone monomethyl ether; lactic acid;
Oxalic acid; benzoic acid; copper naphthenate, etc. can be added.

Furthermore, dyes or pigments can be added to the masking agent to make it easier to identify.

In order to prevent foam formation and provide leveling properties during Nuclean printing, antifoaming agents such as silicone and fluorine-based agents and poly(
Leveling agents such as meth)acrylates, oligo(meth)acrylates, silicones, etc. can also be added.

In order for the masking agent of the present invention to have preferable suitability for screen printing, the spread meter yield value measured by a spread meter specified in JIS K5701-1980 is usually 80 to 8.600 dyne/d,
It is preferably 100 to 6,000 dyne/m2, more preferably 120 to 3,000 dyne/m2. Spread meter yield value is 80
If the dyne/c is less than 1, the mask agent will flow easily and it will be difficult to draw fine turns.
, 600 dyne/7, it is not preferable because the NuClean passage becomes difficult and suitability for screen printing deteriorates.

The spread meter yield value of the mask agent of the present invention is 80~
In order to adjust to 8,600 dyne/cm and achieve preferable flowability, diene oligomers and monomers are used.

It is necessary to use the proportions of plasticizers, thickeners, photopolymerization initiators, and other additives within the following ranges.

Usage ratio of diene oligomer and monomer (weight ratio)
is diene oligomer:monomer=90:10-10
:9Q, preferably 80:20~go
: 70. If the number of diene oligomers is less than 10, rubber-like film characteristics suitable for peeling cannot be obtained.
Moreover, if it is larger than 90, the viscosity becomes high and favorable flow characteristics cannot be obtained.

The plasticizer is preferably used in combination to improve the mold releasability of the cured film and impart flexibility.Amount used: 0 to 100% by weight, preferably 10 to 100% by weight, based on the diene oligomer. It is 50% by weight.

If the amount is 100% by weight or more in the case of dogs, the film strength decreases and peeling becomes difficult. Moreover, the heat resistance of the masking agent decreases.

Furthermore, a part of the plasticizer may remain as a residue after peeling, which is not preferable.

The thickener is usually 0% of the total of the diene oligomer, monomer, plasticizer added if necessary, and other additives.
．． 1 to 15% by weight, preferably 0.5 to 12% by weight.
More preferably, a weight range of 1.0 to 10 is used. 0
．． If it is less than 1% by weight, the spread meter yield value will be small, and if it is 15% by weight, the yield value will be small.
The spread meter yield value becomes too large, and in either case, suitability for screen printing becomes poor. Further, in particular, if the amount of inorganic thickener used is 15% by weight or more, curing with active energy rays becomes difficult, which is not preferable.

The composition of the present invention can be cured by active energy rays such as ultraviolet rays and electron beams.

Among these, when curing by ultraviolet irradiation, it is necessary to add a photopolymerization initiator or a combination of a photopolymerization initiator and a sensitizer in advance. The amount of these used is usually 0.1 to 0.1 to the total of the diene oligomer, monomer, plasticizer and other additives added as necessary.
15% by weight, preferably 1-10% by weight. 0.
If it is less than 1% by weight, UV curing will be difficult, and if it is more than 15% by weight, there will be a large amount of excess. Moreover, when curing by electron beam irradiation, these photopolymerization initiators and sensitizers are not particularly required.

Any method can be used to produce the masking agent of the present invention. Examples include a method of mixing and dissolving a diene oligomer and a hexamer, then adding a thickener and stirring and mixing, and a method of stirring and mixing these components at once. Components such as a plasticizer and a photopolymerization initiator can be added at any stage as required. The mixing temperature is preferably room temperature to 6Q'O to prevent gelation, and the mixing time is not limited, but is usually 10 minutes to 8 hours until uniform mixing is achieved. As the mixing/stirring equipment, a vane type stirrer, a dissol 5-mill, a ball mill, a kneader, a sand mill, a two-roll/three-roll mill, an ultrasonic dispersion machine, etc. can be used.

The masking agent of the present invention is usually prepared by a screen printing method.
It is applied to a printed circuit board and then cured with active energy rays before use. Examples of active energy rays include ultraviolet rays and electron beams, and either of them may be used, but in the case of ultraviolet rays, a photopolymerization initiator is required. As the ultraviolet light source, a high-pressure mercury lamp, a xenon lamp, a metal halide lamp, etc. are used. There are no particular restrictions on the irradiation conditions for both ultraviolet rays and electron beams, and the film thickness after curing is usually 10 μ to 2
Although it has sufficient solder heat resistance and plating solution resistance, it may be changed depending on the solder temperature used and other conditions. If the film thickness is less than 10 μm, the cured film becomes easy to break, making peeling difficult. If it exceeds 2, it becomes difficult to harden deep parts, which is not preferable.

The masking agent of the present invention can be applied by coating methods other than screen printing, such as dinuvencer, spatula, bottle transfer method, brush coating,
The non-damask agent of the present invention can also be applied by metal mask printing, etc., and the most suitable application method can be selected depending on the application and the object to be coated.
Usually, it is applied to a printed circuit board, cured with active energy rays, subjected to flux treatment, soldered, and then peeled off.

The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Production Examples and Comparative Production Examples The diene oligomers, monomers, plasticizers/thickeners, photopolymerization initiators, and other additives shown in Table 1 were charged into a mixing and dissolving vessel equipped with a blade-type stirrer for high viscosity, and the mixture was heated at room temperature. The mixture was mixed and dissolved for 8 hours to obtain a uniform masking agent. The spread meter yield value of the obtained mask agent was determined according to JIS K5701-19.
80.

*1. Idemitsu Petrochemical ■ Collection *20 Nippon Zeon ■ *30 Nippon Petrochemical ■ Collection *4. Half-moon rubber ■I Examples and comparative examples The masking agents of the manufacturing examples and comparative manufacturing examples were mixed with 70 mesh polyester Nuclean with an emulsion thickness of 250μ and hard g 65
Copper null hole using silicone rubber squeegee
After coating on a glass epoxy board, the output is 160W.
/cIrL high pressure mercury lamp for 5 seconds to cure. However, in Example 2, instead of UV irradiation, BM rad electron beam irradiation was used for curing. At this time, the cured film thickness was 200μ, and after applying the flux,
Then, after soldering by immersing in a molten solder bath at 260"C for 3 seconds, the masking agent was peeled off. Meanwhile, in the same manner, the masking agent was applied and cured copper through-hole glass, epoxy Gold cyanide resin substrate, KC
It was immersed in a normal plating bath of N.Na2HPO4 at 55°C for 10 minutes. Then, the masking agent was peeled off.

The results are shown in Table 2.

〔Effect of the invention〕

The masking agent of the present invention is capable of Nuclean printing force,
Capable of printing fine patterns accurately. It has sufficient blacks resistance, no-da heat resistance, and plating solution resistance, and can be easily peeled off and removed after no-da or plating treatment.
Since no residue remains, it has the effect of not deteriorating the electrical characteristics of the substrate.

Claims (1)

[Claims] Diene oligomer having at least one acryloyl group or methacryloyl group in the molecule: 10-
80 parts by weight, monomer having ethylenically unsaturated group: 2
0 to 90 parts by weight, plasticizer: 0 to 80 parts by weight, photopolymerization initiator: 0 to 15 parts by weight, and thickener: 0.1 to 15 parts by weight, spread meter yield value 80 to 8600 d.
yne/cm^2 solder and plating mask agent.