JPH0291171A - Coating composition - Google Patents

Abstract

PURPOSE:To obtain a coating composition improved in adhesion to rubber, synthetic resin, fiber or the like and giving a coating film improved in abrasion resistance by mixing a specified urethane prepolymer with a fluorocarbon resin, a silicone oil, a halogenating agent and a solvent. CONSTITUTION:An NCO-containing urethane prepolymer (A) is obtained by reacting a polyol (e.g., polyoxypropylene glycol of a number-average MW of 800-6000) with caster oil polyol and a polyisocyanate (e.g., 4,4'-diphenyl-methane diisocyanate) at 50-130 deg.C for 60-360min in a nitrogen gas. 100 pts.wt. component (A) is mixed with 2-100 pts.wt. fluorocarbon resin (B) (e.g., polytetrafluoroethylene), 5-100 pts.wt. silicone oil (C) (e.g., dimethylsilicone oil), 0.002-20 pts.wt. halogenating agent (D) (e.g., trichloroisocylanuric acid) and 10-90 pts.wt., per 100 pts.wt. obtained composition, solvent (e.g., trichloroethylene) (E).

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a coating composition for coating rubber products, synthetic resin products, etc.

[Conventional technology]

Conventionally, natural rubber (NR), styrene-butadiene copolymer rubber (SBR), butadiene rubber (BR), isobutylene-isoprene copolymer rubber (IIR), chloroprene rubber (CR), acrylonitrile-butadiene copolymer rubber (NBR), isoprene Rubber (IR), ethylene-
Nylon-based,
Epoxy-based, acrylic-based, acrylic-ethylene copolymer-based resin paints, or rubber-based paints such as BR, CR, and SBR are used.

[Problem to be solved by the invention]

The conventional resin-based paints and rubber-based paints described above have poor adhesion to the objects to be coated, such as rubber, synthetic resins, and fibers, which may cause the paint to peel off from the objects to be coated, or the abrasion resistance of the resulting coating film may deteriorate. There was a problem that it was inferior. An object of the present invention is to provide a coating composition that provides a coating film with excellent abrasion resistance and good adhesion to objects to be coated. [Means for Solving the Problems] In order to achieve the above object, the coating composition of the present invention contains 2 parts by weight of a fluororesin per 100 parts by weight of a urethane prepolymer comprising a polyol, a castor oil polyol, and a polyisocyanate and having an isocyanate group. ~100 parts by weight,
5 to 100 parts by weight of silicone oil and 0.0 parts by weight of halogenating agent. A method of disposing 2 to 20 parts by weight of OO is adopted. [Detailed Description of Means] First, the urethane prepolymer used in the present invention will be described. Polyols include polyoxypropylene glycol (PPG), propylene oxide adduct of glycerin, propylene oxide adduct of trimethylolpropane, propylene oxide adduct of pentaerythritol, triethylene glycol (TG), and propylene oxide adduct of sucrose. Examples include compounds such as The above polyoxypropylene glycol has a number average molecular weight of 80
A value in the range of 0 to 6000 is preferred. Polyisocyanate is a compound having a plurality of isocyanate groups, such as 2,4-1-lylene diisocyanate (TDI), a ratio of 65/35 (2,4-tolylene diisocyanate and 2,6-)lylene diisocyanate, or the following. Similar) Tolylene diisocyanate, 80/2
0-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), dianisidine diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, metaxylene diisocyanate,
l,5-naphthalene diisocyanate (NDI), hydrogenated 4,4'-diphenylmethane diisocyanate, hydrogenated xylene diisocyanate, hydrogenated 2,4-)lylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 80/20 tri Diisocyanate, isophorone diisocyanate (IPDI), 4.4', 4"
-triphenylmethane triisocyanate, tris(,
p-isocyanate phenyl) thiophosphate, etc. are used. Next, the components to be added to the urethane prepolymer will be explained. As the fluororesin, polytetrafluoroethylene, polychlorotrifluoroethylene, trifluoroethylene, vinylidene fluoride, etc. are used. The blending ratio of this fluororesin is in the range of 2 to 100 parts by weight based on 100 parts by weight of the urethane prepolymer. If it is less than 2 parts by weight, the resulting coating film will have poor abrasion resistance, and if it exceeds 100 parts by weight, it will be difficult to apply the coating composition. As the silicone oil, dimethyl silicone oil, methyl chloride silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, fluorosilicone oil, etc. are used. The blending ratio of the silicone oil is 5 to 100 parts by weight based on 100 parts by weight of the urethane prepolymer. If the amount is less than 5 parts by weight, the wear resistance cannot be improved. Furthermore, even if the amount exceeds 100 parts by weight, the effect of improving wear resistance remains the same, but the adhesion deteriorates on the contrary. As a halogenating agent, N-promsuccinimide (N
BSI), acid imide halogen compounds such as N-bromphthalimide, trichloroisocyanuric acid (TCI),
A) Isocyanuric acid halides such as dichloroisocyanuric acid, halogenated hydantoins such as dichlorodimethylhydantoin, alkyl hypohalides, etc. are used. The above-mentioned alkyl hypohalides are normal, secondary or tertiary alkyl hypohalides, particularly stable tertiary alkyl chlorides and bromides, such as tertiary butyl hypochloride (t-BHC), tertiary butyl hypohalides, Preferred are butylhypobromide, tertiary amylhypobromide, and the like, and halogen-substituted alkylhypochlorides such as dichloro, trichloro, or fluoromethylhypochloride can also be used. The halogenating agent is blended in an amount of 0.002 to 20 parts by weight based on 100 parts by weight of the urethane prepolymer. When the blending ratio is less than 0.002 parts by weight, the degree of chlorination is small, so there is little improvement in adhesion, and when it exceeds 20 parts by weight, the stability of the coating composition deteriorates. Solvents that may be used as desired include benzene, toluene, xylene, ethylbenzene, ethylene chloride, dimethylformamide (DMF), dimethyl sulfoxide, methyl ethyl ketone, atocene, methyl isopropyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, and acetic acid. Isopropyl, n-butyl acetate, isobutyl acetate, anisole, tetrahydrofuran, methylene chloride, l,1.1-)lychloroethane, n-hexane, cyclohexane, and the like. The blending ratio of this solvent is 10 parts by weight in 100 parts by weight of the coating composition.
A range of 90 parts by weight is preferred. If the blending ratio is less than 10 parts by weight, the solid content will be relatively high and the viscosity of the coating composition will increase, making coating work difficult and likely resulting in a decrease in adhesion; if it exceeds 90 parts by weight, On the contrary, the proportion of solids becomes low and the film thickness of the coating composition becomes thin, which is not preferable as a coating material. The coating composition of the present invention is prepared, for example, as follows. First, the polyol, castor oil polyol, polyisocyanate and necessary solvent are appropriately selected and mixed,
This was heated in dry nitrogen gas at 50-130°C and 60-360°C.
A urethane prepolymer having isocyanate groups is prepared by reacting for minutes. Next, 2 to 100 parts by weight of a fluororesin, 5 to 100 parts by weight of silicone oil, and 0.002 to 0.002 parts by weight of a halogenating agent are added to 100 parts of this urethane prepolymer.
Add 20 parts by weight, and further add a solvent to adjust the viscosity to be suitable for coating. In this case, part of the fluororesin may be molybdenum disulfide, glass fiber, carbon fiber, polyethylene,
It can also be replaced with silicon oxide, calcium carbonate, magnesium carbonate, clay, etc. [Function] By adopting the above means, the coating composition improves the abrasion resistance of the resulting coating film due to the characteristics such as the lubricity of the silicone oil and the low coefficient of friction of the fluororesin, and also improves the abrasion resistance of the resulting coating film. The coating material is halogenated, and the adhesion to the coating material is improved due to the properties of the urethane prepolymer, which is composed of a polyol, a castor oil polyol, and a polyisocyanate, and has a specific structure having an isocyanate group. [Example 1 to 16 and Comparative Examples 1 to 10] Examples embodying the present invention will be described below in comparison with comparative examples. First, the object to be coated is a vulcanized product as shown below. That is, the vulcanizate contained 100 parts by weight of EPDM (hereinafter simply referred to as "parts"), 70 parts of carbon black, 35 parts of mineral oil, 7 parts of zinc oxide, 2 parts of stearic acid, 2 parts of vulcanization accelerator, and 1 part of sulfur.
．． A composition consisting of 5 parts was vulcanized at 160°C for 30 minutes. In addition, the wear resistance test was conducted by the following method, and the wear resistance was evaluated based on the amount of wear loss. That is, Test machine: Taper type rotary abrader (manufactured by Toyo Seiki Seisakusho Co., Ltd.) Test conditions: Wear wheel: H-22, Load: 1 kg, Wear rotation speed i60 rpm Sample size: 10100 mm x 100 Number of wear: 1000 times In No. 16, each coating composition was applied to the object to be coated and dried in the same manner as in Example 1, and the abrasion resistance test was conducted on it in the same manner as in Example 1. (Example 1) First, a urethane prepolymer was manufactured as follows. PPG2000 (weight average molecular weight approx. 2000) 100
parts, castor oil polyol (hydroxyl value 80) 100 parts, M
75 parts of D I and 140 parts of trichlorethylene were mixed and reacted in dry nitrogen at 80° C. for 3 hours to obtain a urethane prepolymer. Next, to 100 parts of this urethane prepolymer, 10 parts of fluororesin, dimethyl silicone oil [kinematic viscosity: 1
Ten thousand centistokes (Cst) 1 10 parts, TCI
A coating composition was obtained by mixing the AI part. Applying this coating composition to the vulcanizate as the object to be coated,
It was dried at 80°C for 20 minutes. Regarding this, a wear resistance test was conducted. The results are shown in Table 1 below. (Example 2) A coating composition was obtained in the same manner as in Example 1 except that the amount of MDI used in Example 1 was changed to 100 parts. (Example 3) A coating composition was obtained in the same manner as in Example 1 except that the amount of MDI used was 125 parts. (Example 4) In Example 1, dimethyl silicone oil (kinematic viscosity 60,000 Cst) was replaced with 10 parts of dimethyl silicone oil (kinematic viscosity 10,000 Cst).
) A coating composition was obtained in the same manner as in Example 1 except that the amount was changed to 15 parts. (Example 5) Same as Example 1 except that 20 parts of dimethyl silicone oil (kinematic viscosity 100,000 Cst) was used instead of 10 parts of dimethyl silicone oil (kinematic viscosity 100,000 Cst) in Example 1. A coating composition was obtained. (Example 6) In Example 1, 100 parts of PPG2000 (weight average molecular weight 2000) and 100 parts of castor oil polyol (hydroxyl value 80) were replaced with 50 parts of PPG2000 (weight average molecular weight 2000) and castor oil polyol (
A coating composition was obtained in the same manner as in Example 1 except that the hydroxyl value was 80) and 150 parts. (Example 7) In the above Example 1, 150 parts of PPG2000 (weight average molecular weight 2000) and castor oil polyol (
A coating composition was obtained in the same manner as in Example 1 except that the hydroxyl value was 80) and 50 parts. (Example 8) A coating composition was obtained in the same manner as in Example 1, except that 80 parts of castor oil polyol (hydroxyl value 86) was used instead of 100 parts of castor oil polyol (hydroxyl value 80) in Example 1. . (Example 9) A coating composition was obtained in the same manner as in Example 1, except that 70 parts of castor oil polyol (hydroxyl value 92) was used instead of 100 parts of castor oil polyol (hydroxyl value 80) in Example 1. . (Example 10) In Example 1, 100 parts of PPG2000 (weight average molecular weight 2000), 100 parts of castor oil polyol (hydroxyl value 80), 75 parts of MD I, and 140 parts of trichlorethylene were replaced with propylene oxide addition of glycerin. body (weight average molecular weight 3000) 150 parts,
Castor oil polyol (hydroxyl value 80) 150 parts, TD1
Except for using 104 parts and 200 parts of trichlorethylene.
A coating composition was obtained in the same manner as in Example 1. (Example 11) In Example 1, instead of 100 parts of PPG2000 (weight average molecular weight 2000), 100 parts of castor oil polyol (hydroxyl value 80), 75 parts of MDI, and 140 parts of trichlorethylene, trimethylolpropane was added with propylene oxide. body (weight average molecular weight 3000) 2
50 parts, castor oil polyol (hydroxyl value 86) 50 parts,
A coating composition was obtained in the same manner as in Example 1, except that MD was 1150 parts and trichlorethylene was 225 parts. (Example 12) In Example 1, t-BHC was used instead of TCIA.
A coating composition was obtained in the same manner as in Example 1 except that . (Example 13) A coating composition was obtained in the same manner as in Example 1 except that NBSI was used instead of TCIA. (Example 14) A coating composition was obtained in the same manner as in Example 1 except that the TCIAI part was changed to 0.002 parts. (Example 15) A coating composition was obtained in the same manner as in Example 1 except that 1 part of TCIA was changed to 0.1 part. (Example 16) A coating composition was obtained in the same manner as in Example 1 except that 1 part of TCIA was changed to 20 parts. Further, as a comparative example, the following coating compositions were prepared, test pieces were made using the paint compositions, and the abrasion resistance test was conducted on the test pieces. The results are shown in Table 2 below. (Comparative Example 1) 100 parts of liquid polybutadiene (trade name: Idemitsu Seal AB-700W, manufactured by Idemitsu Petrochemical Industries, Ltd.) and parts of MDIIO were mixed to prepare a paint. This paint was applied to the object to be coated and cured at room temperature to prepare a test piece. (Comparative Example 2) 100 parts of liquid polybutadiene (trade name: Idemitsu Seal AB-100, manufactured by Idemitsu Petrochemical Industries, Ltd.) and part MDIIO were mixed to prepare a paint. This paint was applied to the object to be coated and cured at room temperature to prepare a test piece. (Comparative Example 3) A 70% methanol solution of N-methoxymethylated nylon (trade name: Torezin M-20, manufactured by Teikoku Kagaku Sangyo Co., Ltd.) was applied to the coated object and cured at room temperature to prepare a test piece. (Comparative Example 4) 100 parts of epoxy resin (trade name: Araldite pza20, manufactured by Nippon Ciba Geigy Co., Ltd.), polyaminoamide (
Made by Nippon Ciba Geigy Co., Ltd. Product name Hardener) 12)
100 parts were mixed to prepare a paint. This paint was applied to the object to be coated and cured at room temperature to prepare a test piece. (Comparative Example 5) 100 parts of epoxy resin (trade name: Araldite GY250, manufactured by Nippon Ciba Geigy Co., Ltd.), polyaminoamide (
Product name Hardener H2)3 manufactured by Nippon Ciba Geigy Co., Ltd.
0 parts were mixed to prepare a paint. This paint was applied to the object to be coated and cured at room temperature to prepare a test piece. (Comparative Example 6) As a paint, a 74% toluene solution of chloroprene rubber (trade name: Bond G2, manufactured by Konishi Co., Ltd.) was applied to the object to be coated, and cured at room temperature to prepare a test piece. (Comparative Example 7) SBR (trade name: Diabond 5010, manufactured by Nogawa Chemical Co., Ltd.) was applied to the coated object and cured at room temperature to prepare a test piece. (Comparative Example 8) As a paint, an acrylic resin emulsion with a non-volatile content of 70% (trade name Diabond DA manufactured by Nogawa Chemical Co., Ltd.) was used.
-830A) was applied to the object to be coated and cured at room temperature to prepare a test piece. (Comparative Example 9) As a paint, an acrylic-ethylene modified emulsion (manufactured by Sunstar Chemical Co., Ltd., trade name: Penguin Cement 138) with a nonvolatile content of 55% was applied to the object to be coated and cured at room temperature to prepare a test piece. . (Comparative Example 10) As a paint, a polyurethane paint (trade name: Diabond DA700E, manufactured by Nogawa Chemical Co., Ltd.) was applied to the object to be coated and cured at room temperature to prepare a test piece. Table 1 As can be seen from Table 1 above, the coating compositions of each example had abrasion loss of 3.0% even after 1000 abrasion tests.
It is extremely small at 5-4.3 mg. The reason why the coating compositions of each example exhibit such excellent abrasion resistance is presumed to be based on the moisture % property of the silicone oil, the low coefficient of friction property of the fluororesin, and the like. In addition, in the coating compositions of each example, the halogenating agent not only halogenates the object to be coated, but also coats the object based on the properties of a urethane prepolymer containing a predetermined amount of polyol, castor oil polyol, and polyisocyanate and having an isocyanate group. Demonstrates excellent adhesion to vulcanized rubber coatings. On the other hand, as can be seen from Table 2, the paint compositions of each comparative example had a large abrasion loss of 482 to 2290 mg, and had poor abrasion resistance. [Effects of the Invention] The coating composition of the present invention has the effect that the resulting coating film has very good abrasion resistance and has excellent adhesion to the object to be coated. Table-2

Claims (1)

[Claims] 1. 2 to 100 parts by weight of fluororesin to 100 parts by weight of a urethane prepolymer containing isocyanate groups consisting of polyol, castor oil polyol, and polyisocyanate.
A coating composition comprising 5 to 100 parts by weight of silicone oil and 0.002 to 20 parts by weight of a halogenating agent.