JPS6229473B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the prevention of adhesion of epoxy resin, and more particularly to an anti-adhesion agent that prevents excess epoxy resin from adhering to lead wires when coating the surface of a capacitor with epoxy resin. 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 will 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.
The so-called liquid drainability was insufficient, and a satisfactory effect could not be obtained. 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 found 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-adhesive agents. (See Japanese Patent Application No. 1983-24359). As a result of further research, the present inventors found that other polymerizable compounds with an alkyl carbon number of 12
When using an alkyl acrylate or alkyl methacrylate having a carbon number of from 4 to 21, at least 40% by weight of a polymerizable compound containing a perfluoroalkyl group having from 4 to 21 carbon atoms and 10% by weight of the alkyl acrylate or alkyl methacrylate. The present invention was completed based on the discovery that a copolymer having a content of more than 1% also has excellent anti-adhesion properties. That is, the gist of the present invention is to provide a polymerizable compound containing a perfluoroalkyl group having 4 to 21 carbon atoms represented by formulas (1) to (6) below, and alkyl having 12 to 21 carbon atoms.
Less than 90% by weight of a polymerizable compound containing an alkyl acrylate or alkyl methacrylate or alkyl methacrylate having a perfluoroalkyl group of 40% by weight or more and more than 10% by weight or more than 60% by weight of an alkyl acrylate or alkyl methacrylate. The present invention relates to an anti-adhesive agent for epoxy resins comprising a copolymer containing the following proportions, and an anti-adhesive agent for epoxy resins prepared by dissolving the anti-adhering agent in an organic solvent or dispersing it in water. 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 the fingertips. 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. Further, the copolymer according to the present invention has the advantage that it is soluble in solvents with a low evaporation rate, such as chlorinated solvents such as methylchloroform, tetrachlorethylene, and trichloroethylene, and provides a composition with an appropriate evaporation rate. In other words, the anti-adhesive agent made of the polymer disclosed in Japanese Patent Application No. 54-24359 is only soluble in fluorinated solvents with relatively low boiling points in most cases, so it is applied to the substrate in the form of an organic solvent solution composition. In this case, trichlorotrifluoroethane (boiling point 47°C) is usually used because it is easily available and has the ability to dissolve. However, with such a composition, an attempt is made to apply the composition uniformly to the surface of the substrate by passing the substrate such as a wire between two rolls moistened with the anti-adhesion agent composition while sandwiching the substrate. In this case, the polymer as an anti-adhesion agent remains on the surface of the roll, making it impossible to uniformly apply the composition and the anti-adhesion agent onto the surface of the substrate. On the other hand, the copolymer according to the present invention is stable even when made into an aqueous dispersion, and thus can impart good anti-adhesion properties to a substrate when anti-adhesion treatment is performed. The polymerizable compound containing a perfluoroalkyl group having 4 to 21 carbon atoms used in the present invention has the formula: (1) (2) Rf(CH ₂ )nOCOCR″=CH ₂ (3) (Four) (Five) (6) RfCH=CH( _CH2 )nOCOCR''= _CH2 [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 the number of carbon atoms 1-10 alkylene group; R'' is hydrogen or a methyl group; R is an alkyl group having 1-17 carbon atoms; n represents an integer of 1-10. ] 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. Therefore, as the content of the polymerizable compound containing the perfluoroalkyl group in the copolymer of the present invention increases, the ability to impart anti-adhesion properties increases. If the content of epoxy resin is at least 40% by weight, at least if the epoxy resin adheres to the substrate, it can be removed with fingertips. Furthermore, when the content is 60% by weight or more, the epoxy resin does not stick, or a very small amount of epoxy resin sticks, but it can provide enough adhesion prevention properties that it can be removed immediately by touching it with a fingertip. In the copolymer according to the present invention, the content of alkyl acrylate or alkyl methacrylate whose alkyl has 12 to 18 carbon atoms is more than 10% by weight and not more than 60% by weight. The greater the number of carbon atoms in the alkyl, the greater the solubility of the copolymer in organic solvents such as methyl chloroform. Therefore, the preferred number of carbon atoms in alkyl is
16-18. When the number of carbon atoms in the alkyl is large, such as 16 to 18, and the content of alkyl acrylate or alkyl methacrylate in the copolymer exceeds 10% by weight, the copolymer can be dissolved in an organic solvent such as methylchloroform. % by weight. Alkyl carbon number is 12-14
If the copolymer has a content of 15% by weight or more and is dissolved at 1% by weight in an organic solvent such as methyl chloroform, some undissolved matter may be observed. However, as described above, if the amount of the polymerizable compound containing a perfluoroalkyl group is at least a specified amount, sufficient adhesion prevention properties can be imparted. The reason why the aforementioned alkyl acrylate or alkyl methacrylate was selected as an essential component of the copolymer constituting the anti-adhesion agent according to the present invention is that these compounds are polymerizable compounds containing a perfluoroalkyl group. This is because it does not inhibit adhesion prevention properties. As shown in the comparative example below,
Isobutyl methacrylate, 2-
Copolymers using ethyl-hexyl methacrylate or the like do not provide satisfactory adhesion prevention properties. However, the copolymer of the present invention contains at least 40% by weight of a polymerizable compound containing a perfluoroalkyl group having 4 to 21 carbon atoms and an alkyl acrylate or methacrylate in which the alkyl has 12 to 18 carbon atoms. Other copolymerizable compounds other than these copolymerizable compounds can be used as a component as long as the alkyl content is at least 10% by weight. However, its content must be up to 15% by weight of the polymerizable compound containing perfluoroalkyl groups, and must not exceed the content of alkyl acrylate or alkyl methacrylate. There are various such other copolymerizable compounds, but the main ones are (1) acrylic acid and methacrylic acid and their methyl, ethyl, butyl, isobutyl, propyl, 2-ethyl-hexyl, Esters such as hexyl, decyl, β-hydroxyethyl or glycidyl esters, (2) acetic acid, propionic acid,
Vinyl esters of fatty acids such as caprylic acid, lauric acid, and stearic acid; (3) styrene compounds such as styrene, α-methylstyrene, and p-methylstyrene; (4) vinyl fluoride, vinyl chloride, and vinyl bromide; Vinyl halides or vinylidene compounds such as vinylidene fluoride and vinylidene chloride, (5)
Allyl esters of fatty acids such as allyl heptanoate, allyl caprylate, allyl caproate, (6) vinyl alkyl ketones such as vinyl methyl ketone and vinyl ethyl ketone, (7) N-methylacrylamide, N-methylolmethacrylamide, methacryl Acrylamides such as glycidyl acids and (8)
Examples include dienes such as 2,3-dichloro-1,3-butadiene and isoprene. 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 with 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 organic solvents include chlorine-based solvents such as methylchloroform, trichlorethylene, and tetrachloroethylene; fluorine-based solvents such as trichlorotrifluoroethane, tetrachlorodifluoroethane, and meta-xylene hexaflulide; hydrocarbons such as toluene, xylene, and benzene; Ketones such as methyl isobutyl ketone and acetone,
Esters such as ethyl acetate and butyl acetate, and ethers such as ethyl ether are used. 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, trimethyloctadecyl ammonium chloride, and the like.
Desirable nonionic emulsifiers include ethylene oxide, hexylphenol, isooctylphenol, hexadecanol, oleic acid, and 12 carbon atoms.
It includes condensation products with alkanethiols having 16 to 16 carbon atoms, alkylamines having 12 to 18 carbon atoms, and the like. To impart anti-stick properties to a substrate, it is sufficient to immerse the substrate, for example the leads of a capacitor, in the inhibitor composition and allow it to air dry. Next, the present invention will be explained in more detail by showing Examples and Comparative Examples. Example 1 (Weight ratio of compounds with n=3,4,5 4:2:1
mixture) 25.6g and stearyl acrylate
Dissolve 6.4g in 200g of methylchloroform,
The mixture is placed in a 300 ml four-necked flask, and after replacing the air inside with nitrogen gas, a 70% by weight solution of paraffin containing 0.3 g of t-butyl peroxypivalate is added dropwise, and a polymerization reaction is carried out at 55°C for 7 hours. Then, t-
A solution of 0.3 g of butyl peroxypivalate was added dropwise, and the polymerization was further continued at the same temperature for 7 hours. By this polymerization reaction, 230 g of a solution containing 13.7% by weight of copolymer
I got it. Example 2 40g and lauryl methacrylate 20g, cationic surfactant: cationic AB (manufactured by NOF Corporation) 1.5g and nonionic surfactant: nonionic HS-220 (manufactured by NOF Corporation) 2.2g, acetone 45g, ethylene glycol 3g and pure water
Put 123.3g into a 300ml flask, replace the air inside with nitrogen gas, raise the temperature to 60°C, and continue stirring for 30 minutes. Next, a solution of 0.30 g of azobisisobutyronitrile amidine hydrochloride in 5 g of water is added to the flask, and emulsion polymerization is directly carried out. This polymerization reaction resulted in 238 g of an aqueous dispersion containing 23.7% by weight of the copolymer.
I got it. Examples 3 to 9 and Comparative Examples 1 to 7 The solubility and anti-adhesion properties of various copolymers were tested. The solubility in organic solvents is about 15% by weight stock solution of the copolymer obtained by polymerizing in methylchloroform, and 0.5 to 2% by weight in methylchloroform at room temperature.
It was determined by diluting the liquid to a concentration of 100 ml and visually observing whether the liquid was clear or cloudy. The anti-adhesion properties were tested for anti-adhesion properties during room temperature curing and anti-adhesion properties during heat curing. For organic solvent solution compositions, the anti-adhesion property when cured at room temperature is determined by immersing 10 cm from the tip of the capacitor lead wire in the 0.5 to 2% by weight methyl chloroform solution, pulling it out, and then leaving it indoors in a windless environment for 1 minute (25 cm).
℃), then apply epoxy resin for capacitors (viscosity 5000c.s.) to the tip of the lead wire for 20 minutes.
After soaking in cm, it was left indoors in a windless state for 1 minute and the anti-adhesion properties were observed. The determination criteria in this case are as follows. ◎ Eyelash epoxy resin does not adhere to the area where the anti-adhesion agent has been applied. 〇 A small amount of epoxy resin (approximately 10% or less of the lead wire surface) is attached to the area where the anti-adhesion agent is applied. ▲ More than just a small amount of epoxy resin adheres to the area where the anti-adhesion agent is applied. The anti-adhesion property of the epoxy resin when cured by heating was determined by observing the anti-adhesion property of curing at room temperature (5 minutes after lifting), then curing the epoxy resin by heating it at 120℃ for 1 hour, and observing the anti-adhesion property of the epoxy resin. did. The determination criteria in this case are as follows. ◎ Eyelash epoxy resin does not adhere to the area where the anti-adhesion agent has been applied. 〇 A small amount of epoxy resin adheres 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. These results are shown in Table 1. The copolymer used in the solution composition was polymerized in accordance with Example 1. In an aqueous dispersion composition, the anti-adhesion property when cured at room temperature is as follows:
After soaking and pulling up the epoxy resin for capacitors (viscosity
5000c.s.) from the tip of the lead wire, and
The adhesion prevention properties were observed after being left indoors in a windless state (25°C) for a minute. The criteria in this case are the same as in the case of organic solvent solution compositions. The observation and criteria for anti-adhesion properties during heat curing are the same as in the case of organic solvent solution compositions. The results are shown in Table 2. The copolymer used in the aqueous dispersion composition was polymerized in accordance with Example 2.

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Claims (1)

[Claims] 1 Formula: (1) (2) Rf(CH ₂ )nOCOCR″=CH ₂ (3) (Four) (Five) or (6) RfCH=CH( _CH2 )nOCOCR''= _CH2 [wherein, 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 alkylene group of 1 to 10; R'' is hydrogen or a methyl group; R''' is an alkyl group of 1 to 17 carbon atoms; n represents an integer of 1 to 10. Polymerizable compounds containing fluoroalkyl groups and alkyl having 12 or more carbon atoms
Less than 90% by weight of a polymerizable compound containing an alkyl acrylate or alkyl methacrylate or alkyl methacrylate having a perfluoroalkyl group of 40% by weight or more and more than 10% by weight or more than 60% by weight of an alkyl acrylate or alkyl methacrylate. An anti-adhesive agent for epoxy resins consisting of a copolymer containing the following proportions. 2. The anti-adhesion agent for epoxy resins according to claim 1, which is obtained by dissolving the copolymer in an organic solvent or dispersing it in water.