JPS6140689B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an epoxy composition with excellent antistatic properties, and in particular provides a composition useful as a coating material. Conventionally, commonly used epoxy resin paints require heating at high temperatures or being left for long periods of time to harden, making them impractical in terms of productivity and the like. Therefore, the present inventors have focused on a paint that can be cured at low temperatures and in a short time, which is composed of an unpolymerized epoxy compound and an aryldiazonium compound, and which polymerizes and hardens by irradiation with ultraviolet light. This ultraviolet curable epoxy paint itself has a fairly low static charge, and can be applied to, for example, a vinyl chloride resin molded article to improve the antistatic properties of the molded article. However, it has been found that the above-mentioned epoxy paint gradually loses its antistatic properties when exposed outdoors after application. Therefore, the present inventors conducted various studies with the aim of obtaining an epoxy composition that would not lose its antistatic properties even when used outdoors, and as a result, they arrived at the present invention. That is, the gist of the present invention is that the epoxy monomer and/or
Or a mixture consisting of 100 parts by weight of a low polymer and a photosensitive aryldiazonium compound with a molecular weight of about 1000
-5000 ethylene oxide and/or propylene oxide polymer in an amount of 1 to 10 parts by weight. The present invention will be explained in detail below. The composition of the present invention is useful as a raw material for molding various articles by a casting method, etc., and as a paint for coating various plastic molded articles, but is particularly useful for plastic building materials, agricultural and horticultural materials, etc. It is suitable for applying to molded products that are often used outdoors, such as, to impart lasting antistatic properties and good weather resistance to the molded products. Each component of the composition of the present invention will be explained in turn below, and in the following explanation, "parts" indicating the amount added means "parts by weight." The epoxy monomer that is the main component of the composition of the present invention has an epoxy ring represented by the following structural formula.

[Formula] (In the formula, R ₁ , R ₂ , R ₃ and R ₄ are alkyl, aryl, alkoxy, alkenyl and hydrogen.) Examples of the above monomers include ethylene oxide and homologs thereof; glycidic acid and glycidyl. Esters; glycidyl methacrylate, acrylate and crotonate; and allyl glycidyl ether. Further, the epoxy is a low polymer containing the above-mentioned monomers and may be post-curable, and is particularly preferably liquid at room temperature. In the following explanation, the term epoxy monomer includes its low polymer. Next, the photosensitive aryldiazonium compound used in the present invention is represented by the following structural formula. (In the formula, MXn+m is a complex anion containing a halogen selected from hexachlorostannate, tetrachloropherate, hexafluoroarsenate V, hexachloroantimonate V, hexafluoroantimonate V, and bismuth chloride; Y is selected from the group consisting of nitro, halogen, N-morpholino, alkyl, alkoxy, aryl, amino, arylamino, alkylamino, and arylmercapto groups. In addition, m is the number of halogen atoms in the Lewis acid produced upon UV irradiation. In other words, it corresponds to the charge of the complex cation.) When exposed to ultraviolet light, the aryl diazonium compound transforms into a Lewis acid represented by the general formula MXn (i.e., PF ₃ , Fecl ₃ , AsF ₅ , SbF ₅ , Sncl ₄ and
Bicl _3, etc.), and the Lewis acid initiates the polymerization of epoxy monomers. Examples of the aryldiazonium compound include diazonium hexafluorophosphate such as P-methoxybenzenediazonium hexafluorophosphate, 0-nitrobenzenediazonium hexafluorophosphate, 2,5-dichlorobenzenediazonium hexafluorophosphate, and P-N- Examples include N-morpholino complexes such as morpholinophenyldiazonium hexafluorophosphate, 2,5-dimethoxy-4-N-morpholinobenzenediazonium hexafluorophosphate, and PN-morpholinophenyldiazonium hexafluoroantimonate. The aryldiazonium compound is used in an amount of about 1 to 10 parts per 100 parts of the epoxy monomer. The present invention further provides the epoxy monomer and the aryldiazonium compound with a molecular weight of approximately 1000 to 5000.
of ethylene oxide and/or propylene oxide to impart lasting antistatic properties to the composition. It is known that various surfactants can be added to impart antistatic properties to resins, but
In the case of UV-curable epoxy, when anionic or cationic surfactants were used, problems such as inhibition of the curing reaction occurred. On the other hand, nonionic surfactants do not have problems such as inhibiting the curing reaction and exhibit good antistatic properties, but if they do not contain ethylene oxide and/or propylene oxide units, they may It was found that it gradually lost its antistatic effect and was not suitable for preventing static electricity in products used outdoors. In addition to poly(ethylene oxide), the ethylene oxide polymer referred to in the present invention includes polyoxyethylene nonyl phenyl ether, polyoxyethylene glycidyl ether, and polyoxyethylene phenyl glycidyl ether. Those containing propylene oxide instead of ethylene oxide, and those containing both ethylene oxide and propylene oxide include block copolymers of both. The molecular weight of the polymer must be within the range of about 1000 to 5000; anything smaller than that is likely to bloom, and durable antistatic properties cannot be obtained, and anything larger than that is likely to cause problems with epoxy monomers. The compatibility is poor, the resulting composition has poor transparency, and is also unfavorable from the viewpoint of workability. The amount of the polymer added is the epoxy monomer
The amount is 1 to 10 parts, preferably 2 to 5 parts per 100 parts. If the amount added is less than 1 part, the antistatic effect will not be sufficient, and if it exceeds 10 parts, disadvantages such as deterioration of the physical properties of the composition and inhibition of the curing reaction will occur. When the composition described above is used for coating the surface of a molded product, it may be applied using a normal bar coater, roll coater, etc., or may be applied by a spray method, dipping method, etc. You can also do that. The coating thickness depends on the application, but
It is usually in the range of about 1 to 30μ. After application, let stand for several seconds to several minutes, and then irradiate the coating film for about 0.5 seconds to 1 minute with an ultraviolet irradiation device (e.g., mercury lamp, xenon lamp, tungsten filament lamp, etc.) to decompose the photosensitive aryldiazonium compound. A Lewis acid is produced, which acts as a polymerization initiation catalyst, and the epoxy monomer is polymerized and cured. In addition, when applying the composition of the present invention to the surface of a molded product, in order to improve the adhesion between the molded product and the coating film, there are methods of preheating the surface of the molded product or the coating composition to a temperature below the heat-resistant temperature of the plastic molded product, It is also possible to adopt a method in which the surface of the molded product is dissolved or swollen in advance with an appropriate solvent to improve the adhesion of the coating film, and in these cases, the ethylene oxide polymer etc. do not pose any problem. . The composition of the present invention is particularly suitable because when applied to a polyvinyl chloride resin molded article, good adhesion can be obtained and the weather resistance of the polyvinyl chloride resin can be improved. The present invention will be explained below with reference to Examples. Example 1 An extruded sheet with a thickness of 2 mm was molded from the following formulation. Vinyl chloride homopolymer (average degree of polymerization 800)
...100 parts dibutyltin malate ester ...3 parts Lubricant (Wax OP) ...0.3 parts On one side of the sheet, 100 parts of an epoxy compound (Ultraset ADX-800 manufactured by Asahi Denka Co., Ltd.), p-methoxybenzenediazonium hexane A coating liquid consisting of 3 parts of fluorophore (PS-33 manufactured by Asahi Denka Co., Ltd.) and additives of the type and amount shown in Table 1 was applied to a thickness of 10 μm using a roll coater at a sheet temperature of 80° C. Then, after being allowed to stand for 1 minute, the coating film was irradiated with ultraviolet rays for 5 seconds using a high-pressure mercury lamp to cure the coating film, thereby obtaining a coating sample. Each sample was examined for chargeability, compatibility of additives during coating, and curing inhibition.
The results are shown in Table 1. The charging property was determined in accordance with JIS-L-1018, and a cotton cloth was brought into contact with the coated surface of the coated sample under a load of 400 grams, and the frictional charging voltage was measured after rubbing for 1 minute at a drum rotation rate of 450 times/minute. As shown in Table 1, anionic (sample No. 3)
and amphoteric (No. 5) additives are easily dissolved in epoxy compounds, but they instantly react with diazonium compounds and foam and cannot be cured, while cationic (No. 4) additives dissolve in epoxy compounds. does not dissolve in The present invention (No. 6) does not have this problem and good results can be obtained.

[Table] Example 2 Coating samples were prepared in the same manner as in Example 1, except that 3 parts of each of the types of additives shown in Table 2 were used in the coating liquid. Next, each sample was subjected to a weathering test according to JIS-A-1415, and weathering 500,
Chargeability for samples after 1000 and 1500 hours,
and light transmittance (JIS-K-6714) were measured.
The results are shown in Table 2. Note that EO-PO in Samples Nos. 10 to 13 represents a block copolymer of ethylene oxide and propylene oxide, and among these, Samples Nos. 11 and 12 are products coated with the composition of the present invention.

[Table] Example 3 Poly(propylene oxide) as an additive
Coating samples were prepared in the same manner as in Example 1, except that (molecular weight: 2000) was added in the amounts shown in Table 3. The ultraviolet irradiation time required to cure to a certain degree was compared. The surface smoothness was measured using a stylus surface roughness meter (Talysurf Model 4 manufactured by Taylor Hobson).
Roughness was expressed as a 10-point average roughness according to JIS B 0601-1976. It can be said that the smaller this value is, the better the coating property is.

【table】

【table】

Claims (1)

[Claims] 1. An epoxy composition in which 1 to 10 parts by weight of a polymer of ethylene oxide and/or propylene oxide having a molecular weight of 1000 to 5000 is added to a mixture consisting of 100 parts by weight of an epoxy monomer and/or low polymer and a photosensitive aryl diazonium compound.