JPH0355972B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the prevention of adhesion of epoxy resin, and more particularly, the present invention relates to a method for preventing excess epoxy resin from adhering to lead wires when coating the surface of a capacitor with epoxy resin, an anti-adhesion agent, and an anti-adhesion agent composition. relating to things. Epoxy resin is often used as a moisture-proof protective material for ceramic capacitors, chemical capacitors, etc., but the surface of the capacitor is coated with such a moisture-proof protective material by dipping the capacitor in the moisture-proofing agent, pulling it out, and curing it. . However, during coating, epoxy resin may adhere to the lead wires attached to the capacitor body, but if you try to mount such a capacitor on a printed circuit board, for example, the epoxy resin adhering to the lead wires may become an obstacle. This may cause the inconvenience of not being able to wire properly. As shown by the fact that epoxy resin is frequently used as an adhesive, it has a strong adhesive force to lead wires, and once attached, cannot be easily removed. Conventionally, silicone oil emulsions have been used to prevent epoxy resin from adhering to lead wires, but the epoxy resin's anti-adhesion properties, so-called liquid removal properties, have been insufficient, and a satisfactory effect has not been achieved. Nakatsuta. In addition, in order to increase the effectiveness, if the concentration of silicone oil is increased and it is applied to the lead wires, a thin film is formed on the lead wires due to the creeping property of the silicone oil. There was a drawback that electrical conduction failure occurred at the connecting portion of the conductor wires, causing malfunction of the assembled device. The present inventors focused on these problems associated with capacitor manufacturing, and developed a method and anti-adhesive agent to prevent epoxy resin from adhering to lead wires during capacitor manufacturing, and even if it does adhere, it can be easily removed with a fingertip etc. As a result of repeated research into an anti-adhesive agent that doubles as a mold release agent to allow the epoxy resin to separate,
It has been discovered that homopolymers of polymerizable compounds containing perfluoroalkyl groups having 4 to 21 carbon atoms or copolymers with up to 10% by weight of other polymerizable compounds are extremely effective as anti-adhesion agents. Completed the invention. That is, the gist of the present invention consists of a polymerizable compound containing a perfluoroalkyl group having 4 to 21 carbon atoms and a compound copolymerizable therewith;
An anti-adhesive agent consisting of a polymer in which the latter is 100 to 90% by weight and 0 to 10% by weight, an anti-adhesive composition in which the polymer is dispersed in water or dissolved in an organic solvent, and the composition is used as a substrate. It consists in a method of imparting anti-adhesion properties to a substrate by coating and then drying and removing the water or solvent. When the anti-adhesion agent of the present invention is applied to a substrate, such as a metal wire, the epoxy resin does not adhere to the substrate, and even if it does, it can be easily removed with a fingertip. Moreover, even when the base body, for example, the metal wire, is connected to another metal by soldering, it does not have any adverse effect on the soldering characteristics, and does not cause poor electrical conductivity. The polymerizable compound containing a perfluoroalkyl group having 4 to 21 carbon atoms used in the present invention includes various compounds having a perfluoroalkyl group having 4 to 21 carbon atoms. Specifically, for example, the formula: (2) Rf (CH ₂ ) _o OCOCR″=CH ₂ (6) RfCH=CH(CH ₂ ) _o OCOCR″=CH ₂ [In the formula, Rf is a perfluoroalkyl group having 4 to 21 carbon atoms; R is hydrogen or an alkyl group having 1 to 10 carbon atoms; R′ is a carbon an alkylene group having a number of 1 to 10; R'' is hydrogen or a methyl group; R is an alkyl group having 1 to 17 carbon atoms; n represents an integer of 1 to 10; ] Examples include compounds having a perfluoroalkyl group having 4 to 21 carbon atoms at one end and a carbon-carbon double bond at the other end, as shown in the following. There are various compounds that can be copolymerized with the above compounds, but the main ones are (1) acrylic acid, methacrylic acid, and their methyl, ethyl, butyl, isobutyl, propyl, 2-ethylhexyl, hexyl, Decyl, lauryl, stearyl, β-hydroxyethyl, glycidyl esters, (2) vinyl esters of fatty acids such as acetic acid, propionic acid, caprylic acid, lauric acid, stearic acid, etc., (3) styrene, α-methylstyrene, p −
Styrenic compounds such as methylstyrene, (4) vinyl halides or vinylidene compounds such as vinyl fluoride, vinyl chloride, vinyl bromide, vinylidene fluoride, vinylidene chloride, (5) allyl heptanoate, allyl caprylate, capron Allyl esters of fatty acids such as allyl acids, (6) vinyl alkyl ketones such as vinyl methyl ketone and vinyl ethyl ketone, (7) N-methylacrylamide, N-methylolmethacrylamide, glycidyl acrylate,
Examples include acrylamides such as glycidyl methacrylate and dienes such as (8)2,3-dichloro-1,3-butadiene and isoprene. Among these, acrylic esters, methacrylic esters and styrene compounds are particularly preferred from the viewpoint of ease of copolymerization. The proportion of the polymerizable compound containing a perfluoroalkyl group and the compound copolymerizable therewith in the polymer is preferably 100 to 90% by weight for the former and 0 to 10% by weight for the latter. The anti-adhesive performance is best when a small amount of other copolymerizable compounds are present, and the performance decreases as this amount increases. The polymerization reaction method for producing the polymer used in the present invention can be arbitrarily selected, and any of various polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, and radiation polymerization can be adopted. For example, a mixture of compounds to be copolymerized is dissolved in a suitable organic solvent and subjected to solution polymerization under the action of a polymerization initiation source (such as a peroxide, an azo compound, or ionizing radiation that is soluble in the organic solvent used). Alternatively, a mixture of compounds to be copolymerized is emulsified in water in the presence of a surfactant and emulsion polymerized by the action of a polymerization initiator such as a peroxide, an azo compound, or ionizing radiation. Various types of anionic, cationic or nonionic surfactants are used as the surfactant. The anti-adhesion agent of the present invention is a polymer used in the present invention.
It is used by dissolving 0.2 to 3% by weight, preferably 0.5 to 1.5% by weight in an organic solvent or dispersing it in water with a suitable emulsifier. Suitable solvents include fluorine-based solvents such as trichlorotrifluoroethane, tetrachlorodifluoroethane, and metaxylene hexafluoride. As the emulsifier, various anionic, cationic or nonionic emulsifiers can be used, with cationic and nonionic emulsifiers being particularly preferred. Desirable anionic emulsifiers have 16 to 18 carbon atoms.
Sodium salt of sulfated alkenyl acetate,
Sodium oleate, sodium salt of sulfated methyl oleate, ammonium ω having 8 to 10 carbon atoms
-H-polyfluoroalkanoate, ammonium perfluoroalkanoate, alkyl sodium sulfate having 10 to 18 carbon atoms, 12 to 18 carbon atoms
sodium alkylbenzene sulfonate, and sodium alkylnaphthalene sulfonate. Desirable cationic ones are
(dodecylmethylbenzyl)trimethylammonium chloride, benzyldodecyldimethylammonium chloride, N-[2-(diethylamino)ethyl]-oleamide hydrochloride, dodecyltrimethylammonium acetate, trimethyltetradecylammonium chloride, hexadecyltrimethylammonium chloride, and trimethyloctadecyl Includes ammonium chloride and the like. Desirable nonionic emulsifiers include ethylene oxide, hexylphenol, isooctylphenol, hexadecanol, oleic acid, and
It includes condensation products with 16 alkanethiols, alkylamines having 12 to 18 carbon atoms, and the like. To apply the anti-adhesion agent to a substrate, it is sufficient to dip the substrate, eg, the leads of a capacitor, into the inhibitor composition and allow it to air dry. It is preferable to use a solution type composition because of the ease of air drying and the ease with which the liquid is compatible. Next, the present invention will be explained in more detail by showing Examples and Comparative Examples. In each example, parts or %
Unless otherwise specified, parts or percentages are by weight.
represents. Example 1 (Mixture of compounds with n = 3, 4, 5 in a weight ratio of 4:2:1) 32 g, 0.8 g of 2-ethylhexyl methacrylate and 0.8 g of glycidyl methacrylate were mixed with 23 g of acetone, tetrachlorodifluoroethane.
128g of trichlorotrifluoroethane was dissolved in a mixed solvent of 50g of trichlorotrifluoroethane, placed in a 300ml four-necked flask, and after replacing the air inside with nitrogen gas, t-
Butyl peroxypivalate 3g paraffin 70
% solution was added dropwise and the polymerization reaction was carried out at 55°C for 7 hours.
Then, a solution of 3 g of t-butyl peroxypivalate is added dropwise, and the polymerization is continued at the same temperature for another 7 hours. This polymerization reaction produces a solution containing 14.2% polymer.
230g was obtained. Example 2

[Formula] 30g, emulsifier (dimethyloctadecylamine acetate)
1.5g, acetone 15g and water 165g in 300ml 4
Place in a neck flask, replace the air inside with nitrogen gas while stirring, and heat on a water bath. When the internal temperature reached 55℃, a solution of 0.2g of azobisisobutyramidine hydrochloride in 10g of water was added dropwise, and the polymerization reaction was continued for 2 hours while maintaining the internal temperature at 60℃. 210 g of an emulsified dispersion containing 14% of the homopolymer was obtained. The polymers used in the following Examples 3 to 8 were those obtained in Examples 1 or 2, or those produced in the same manner as in Examples 1 and 2. Examples 3 to 8 and Comparative Examples 1 to 5 2 cm from the end of 7 cm of capacitor lead wire
The parts shown in Table 1 are dipped in each of the anti-adhesion compositions shown in Table 1, and dried at room temperature until the solvent or water is removed. After dipping 5 cm from the end of this lead wire coated with anti-adhesion agent into an epoxy resin composition for capacitors and pulling it up, it was left at room temperature for 10 minutes, and then
Curing is performed in a constant temperature bath at 120°C for 1 hour. The anti-adhesion agent applied portion on the surface of each lead wire subjected to the above treatment was observed, and whether or not the epoxy resin was adhered to the surface was visually judged according to the following criteria. The results are shown in Table 1. Judgment Criteria◎ Epoxy resin does not adhere to the area where the anti-adhesion agent is applied. 〇 There is a small amount of epoxy resin attached to the area where the anti-adhesion agent is applied, but it can be removed immediately by touching it with your fingertips. △ There are patches of epoxy resin attached to the area where the anti-adhesion agent has been applied, which can be removed with your fingertips. × The effect of the anti-adhesion agent is not strong, and the epoxy resin adheres to the areas where it is not applied.

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Claims (1)

[Claims] 1 Homopolymers composed of polymerizable compounds containing perfluoroalkyl groups having 4 to 21 carbon atoms, and 90% by weight or more of polymerizable compounds containing perfluoroalkyl groups having 4 to 21 carbon atoms, and copolymers thereof. applying a copolymer consisting of not more than 10% by weight of possible compounds to the capacitor leads, and then immersing some or all of the capacitor body and the coated parts of the leads in an epoxy resin;
A method for coating the surface of a capacitor with an epoxy resin, which is characterized by curing the epoxy resin at the end.