JPH0431473A - Coating composition and coated object - Google Patents

Abstract

PURPOSE:To obtain a coating composition which gives a highly wear-resistant coating film surface and good adhesion between the film and an object to be coated by compounding a fluororesin and aminosilicone with a specific polyurethane at a predetermined ratio. CONSTITUTION:A coating composition comprising 100 pts.wt. polyurethane, 2-100 pts.wt. fluororesin and aminosilicone at an amino group (-NH2) to isocyanate group (-NCO) molar ratio of 0.7:1 to 1.3:1. The polyurethane comprises a polyol, triethanolamine and a polyisocyanate at a polyol to triethanolamine molar ratio of 1:0.05 to 1:2.0 and a hydroxyl group (-OH) to isocyanate group (-NCO) molar ratio of 1:1.5 to 1:7. A coated object is obtained by coating the surface of a base comprising a resin or rubber with this composition. The object has good wear resistance and good water repellency.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a coating composition, and coating of rubber products such as glass runs, weather strips, double-sided adhesive tapes, synthetic resin products, etc. coated with the coating composition. It's about the body.

[Conventional technology]

Conventionally, natural rubber (NH), 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-
For surface coating of synthetic rubber such as propylene-diene copolymer rubber (EPDM) and ethylene-propylene copolymer rubber (EPM), cotton, rayon, ABS, PS, etc., nylon-based, epoxy-based, acrylic-based, acrylic-ethylene Copolymer resin paints or rubber paints such as BR, CR, and SBR are used.

[Problem to be solved by the invention]

The above-mentioned conventional resin-based paints and rubber-based paints have problems in that they have poor adhesion to coated objects such as rubber, synthetic resins, fibers, etc., and the resulting paint films have poor abrasion resistance.

The purpose of the present invention is to solve the above-mentioned problems, and to provide a coating composition in which the resulting coating film surface has excellent abrasion resistance and good adhesion between the coating film and the object to be coated, and this coating composition. The object of the present invention is to provide a coated body that exhibits properties such as abrasion resistance and water repellency due to the characteristics of the present invention.

[Means to solve the problem]

In order to achieve the above object, the first invention provides a polyol,
Composed of triethanolamine and polyisocyanate, the molar ratio of polyol:triethanolamine is I:0
．． 05 to 2.0 and the molar ratio of hydroxyl group (-OH) to isocyanate group (-NCO) is 1:1.5 to 7.
100 parts by weight of amino silicone with amino groups (-NHz
): The molar ratio of isocyanate groups (-NCO) is 0.7 to
l.

The gist is a coating composition formed by blending the amount of 3:1.

Moreover, the gist of the second invention is a coating body formed by applying the coating composition of the first invention on the surface of a base material made of resin or rubber.

[Detailed explanation of means]

First, the polyurethane used in the present invention will be explained.

Examples of polyols include polyoxypropylene glycol (PPG), propylene oxide adduct of glycerin, propylene oxide adduct of trimethylolpropane, propylene oxide adduct of pentaerythol, triethylene glycol (TG), and propylene oxide adduct of sucrose. Examples include added compounds. The above polyoxypropylene glycol has a number average molecular weight of 800.
A range of 6,000 to 6,000 is preferred.

The amine is triethanolamine, and a crosslinking reaction occurs with monoethanolamine and jetanolamine.
It is unsuitable because polyurethane gels.

Polyisocyanate is a compound having a plurality of incyanate groups, such as 2,4-1-lylene diisocyanate (TD I), 65/35 (2,4=tolylene diisocyanate and 2,6-)lylene diisocyanate. (proportion, same below) trilene diocyanate, 80/
20 tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), dianisidine diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, metaxylene diisocyanate, 1,5-naphthalene diisocyanate (NDI), hydrogenated 4,4'- Diphenylmethane diisocyanate, hydrogenated xylene diisocyanate, hydrogenated 2,4-)lylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 80/20 tolylene diisocyanate, isophorone diisocyanate (IPDI), 4.4' 4
'-) Riphenylmethane triisocyanate, Tris(
p-isocyanate phenyl) thiophosphate, etc. are used.

The molar ratio of the polyol:triethanolamine is 1:
It is 0.05 to 2.0. If this ratio is less than 0.05 or more than 2.0, the adhesion of the resulting coating film to the object to be coated will be greatly reduced.

Further, the molar ratio of hydroxyl group (-OH) in the polyol to isocyanate group (-NCO) in the polyisocyanate is 1:1.5 to 7, and the isocyanate group is blended in excess with respect to the hydroxyl group. This ratio is 1.5
When it is less than 7 or more than 7, the adhesion of the obtained coating film to the object to be coated decreases and may not adhere properly.

Fluororesins include tetrafluoroethylene resin,
Tetrafluoroethylene-hexafluoropropylene copolymer resin, trifluorochloroethylene resin, vinylidene fluoride resin, etc. are used. The blending ratio of this fluororesin is in the range of 2 to 100 parts by weight per 100 parts by weight of the polyurethane. If the proportion is less than 2 parts by weight, the abrasion resistance will not improve, and if it exceeds 100 parts by weight, it will be difficult to apply the coating composition.

As the amino silicone, for example, those having the following structures can be used.

In the above formula, R is CH2 or OCH! , l is 1 to 20
represents an integer. Moreover, m and n are determined based on the amine equivalent.

This amino silicone has a function as a curing agent for the polyurethane, and the molar ratio of amino groups (-NH2) in the amino silicone to isocyanate groups (-NCO) in the polyurethane is 0.7.
~1.3.

When this molar ratio is less than 0.7 or more than 1.3, the adhesion of the resulting coating film to the object to be coated decreases.

In the present invention, a solvent may be added if necessary. Solvents include benzene, toluene, xylene, ethylbenzene, trichloroethylene, ethylene chloride, dimethylformamide, dimethyl sulfoxide, methyl ethyl ketone, acetone, methyl isopropyl ketone,
Methyl isobutyl ketone, methyl acetate, ethyl acetate, isobutyl acetate, -butyl acetate, isopropyl acetate,
Examples include anisole and tetrahydrofuran.

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 leading to a decrease in adhesion. On the other hand, if it exceeds 90 parts by weight, the solid content becomes low (resulting in a thin coating composition), which is not preferable as a coating material.

The coating composition of the present invention is prepared, for example, as follows. First, the polyol, triethanolamine, polyisocyanate and necessary solvent are appropriately selected and mixed,
This is reacted in dry nitrogen gas at 80° C. for 3 hours to prepare a polyurethane having isocyanate groups.

Next, 2 to 100 parts by weight of fluororesin and amino silicone are added to 100 parts by weight of this polyurethane.
The molar ratio of NHri:isocyanate group (-NCO) is 0.
Add in an amount of 7 to 1.3+1. Furthermore, a coating composition is obtained by adding a solvent to adjust the viscosity to be suitable for coating. In this case, a part of the fluororesin may be molybdenum disulfide, glass fiber, carbon fiber, polyethylene, silicon oxide,
It can also be replaced with calcium carbonate, magnesium carbonate, clay, etc.

Further, the base material constituting the coated body of the second invention is resin or rubber. For example, the resin used is vinyl chloride resin, polyethylene, polypropylene, polyurethane, or a foam thereof, and the rubber used is ethylene-propylene-
Diene terpolymer rubber (EPDM), ethylene-propylene copolymer rubber (EPM), etc. are used.

[Effect]

In the coating composition of the first invention, the properties such as the lubricating properties of the amino silicone and the small friction coefficient of the fluororesin improve the abrasion resistance of the resulting coating film surface, and improve the abrasion resistance of the resulting coating film surface. Hydrogen bonding occurs between the isocyanate groups of the polyurethane consisting of a proportion of polyol, triethanolamine, and polyisocyanate and the object to be coated, improving the adhesion of the coating film to the object to be coated.

In addition, since the coated body of the second invention has the above coating composition applied to its surface, it exhibits performance such as abrasion resistance and water repellency based on the characteristics of the coating composition of the first invention. be done.

[Examples 1 to 12 and Comparative Examples 1 to 6] Examples embodying the first invention will be described below in comparison with comparative examples. In addition, parts on each side represent parts by weight.

First, the object to be coated is 100 parts of EPDM and 7 parts of carbon black.
0 parts of mineral oil, 35 parts of mineral oil, 7 parts of zinc oxide, 2 parts of stearic acid, 2 parts of vulcanization accelerator, and 1.5 parts of sulfur.
This is a vulcanized product obtained by vulcanization at 0°C for 30 minutes.

Next, polyol (PO), triethanolamine (TEA), and polyisocyanate (PI) shown in Table 1 were mixed in trichloroethylene and reacted at 80° C. for 3 hours in a nitrogen gas atmosphere to synthesize polyurethane. The obtained polyurethane had a solid content of 83% and a trichlorethylene content of 17%.

The abbreviations in Table-1 represent the following meanings.

PPG 3000: Polyoxypropylene glycol with number average molecular weight J13000 PPG 1000: Polyoxypropylene glycol with number average molecular weight 1000 PPG 2000: Number average molecule! Polyoxypropylene glycol with a number average molecular weight of 2000 TG 3000: Triethylene glycol with a number average molecular weight of 3000 TG 1000: Triethylene glycol with a number average molecular weight of 1000 TG 2000: Triethylene glycol with a number average molecular weight of 2000 MDI: 4,4'-diphenylmethane diisocyanate NDI: 1,5-naphthalene diisocyanate XDI:
Xylylene diisocyanate IPDI: Isophorone diisocyanate TDI+2.4
-1 Lylene diisocyanate-1 Next, predetermined amounts of fuso resin and amino silicone shown in Table 2 below were blended with 100 parts of the solid content of the above various polyurethanes to obtain coating compositions.

represents. Moreover, the molar ratio represents the molar ratio of amino group/isocyanate group.

Further, as a comparative example, a coating composition as shown in Table 3 was prepared. The meanings of the abbreviations in Table 3 are the same as those in Table 2 above.

The fluororesins in Table 2 are tetrafluoroethylene resin, followed by
The coating compositions of Examples 1 to 12 and Comparative Examples 1 to 6 were applied to the objects to be coated and dried at 5.80°C for 20 minutes, and then an abrasion resistance test was conducted under the following conditions. Abrasion resistance was evaluated. The results are shown in Tables 4 and 5.

Test machine: Taper type low clear breather (manufactured by Toyo Seiki Seisakusho Co., Ltd.) Test conditions: Wear wheel, H-22, Load: 1 kg Wear rotation speed: 60 rpm Sample size: 10100 mm x 100 Number of wear, 1000 times Table-5 Above table As can be seen from 4, the coating compositions of Examples 1 to 12 show extremely small abrasion losses of 10.0 to 15.1 mg even after 1000 abrasion tests. The reason why the coating compositions of each example exhibit such excellent abrasion resistance without impairing the material properties of the object to be coated is that the amino silicone has lubricating properties, and the friction of the fluororesin It is presumed that this is based on characteristics such as the small coefficient.

In addition, hydrogen bonding occurs between the isocyanate groups of polyurethane consisting of a predetermined amount of polyol, triethanolamine, and polyisocyanate and the vulcanized rubber to be coated, making the coating composition superior to the vulcanized rubber. Demonstrates adhesion.

On the other hand, as can be seen from Table 5, the coating compositions of Comparative Examples 1 to 6 had a large abrasion loss of 1005.1 to 3951.6 mg, and were inferior in abrasion resistance compared to Examples 1 to 12.

[Examples 13 to 24 and Comparative Examples 7 to 12] Next, examples in which the second invention is embodied in a glass run coated with a coating composition will be described.

A glass run is a member made of synthetic rubber or synthetic resin that is installed to seal the edge of a window glass when the window glass is opened or closed.This glass run requires particular abrasion resistance because the window glass slides. be done.

Therefore, the above-mentioned Examples 1 to 1 were applied to the base material surface of the glass run.
The coating compositions of No. 2 and Comparative Examples 1 to 6 were applied, and the following abrasion resistance test was conducted to evaluate the performance of the glass runs coated with the coatings. The results are shown in Table-6 and Table-7.

Abrasion resistance test: Abrasion resistance was evaluated by abrading the painted surface of the base material coated with the coating composition.

(Test conditions) Testing machine, KI type abrasion tester Abrasion element: Glass (thickness 5+++m) Load: 3kg Abrasion element cycle: 60 times/min Stroke of abrasion element: 145mm (Test method) Attach the above test piece to the testing machine We investigated the condition of the painted surface after it was worn 30,000 times. In the Examples shown in Table 6, those in which the base material was not exposed were judged to be acceptable, and those in which the base material was exposed were judged to be rejected. Further, in the comparative example shown in Table 7, the amount of wear was measured.

Table-6 As seen from Table-6 and Table-7 above, Examples 13-
In Comparative Examples 7 to 12, the abrasion amount was 20 to 3380 mg.
/30,000 times.

[Examples 25 to 36 and Comparative Examples 13 to 18] Next, the second
An example will be described in which the invention is embodied in a weather strip coated with a coating composition.

Synthetic rubber and synthetic resin weather strips are used for car window frames and window glass seals. This weather strip is particularly required to have abrasion resistance because it slides when opening and closing window glass and doors. As the base material of the weather strip, polyolefin vulcanized rubber, such as the aforementioned EPDM or EPM, is used. In addition to these polyolefin-based vulcanized rubbers, natural rubber (NH), polybutadiene rubber (BR), acrylonitrile-butadiene rubber (NBR), polyisoprene rubber (IR), chloroprene rubber (CR), and isobutylene-isoprene rubber are also used. Also used is one in which polymeric rubber (IIR) or the like is blended in an amount of 1/2 or less.

The formulations usually used for the above vulcanized rubbers, namely:
Sulfur, morpholine, disulfide, dicumyl peroxide as a vulcanizing agent, 2-mercaptobenzothiazole, zinc dimethyldithiocarbamate as a vulcanization accelerator,
Tetramethylthiuram disulfide etc. are anti-aging agents,
Phenyl-α-nanthylamine, 2.6-t-butyl-p-cresol, etc. are used as antioxidants and ozone deterioration inhibitors, and carbon black, hydrated silicic acid, etc. are used as fillers.
Magnesium carbonate, clay, etc. are used, and dioctyl sebacate, mineral oil, etc. are used as plasticizers.

Rubber foaming agents include N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl-N,N'-dinitrosoterephthalamide, azodicarbonamide, azobisisobutyronitrile, benzenesulfonylhydrazide, p , p'-oxybis(benzenesulfonylhydrazide), toluenesulfonylhydrazide, etc.
Further, as foaming aids, urea, salicylic acid, etc. are suitably blended depending on the amount of foaming.

For the base material of this weather strip, Examples 1 to 1
The following abrasion resistance test was performed on the coating compositions of Comparative Examples 7 to 12 to evaluate the abrasion resistance. The results are shown in Table-8 and Table-9.

Abrasion resistance test A wear resistance test was conducted using a glass edge abrasion tester, which is an improved version of the Nigakushin abrasion tester, and the abrasion resistance test was conducted under normal conditions under the following test conditions.

Friction element: glass (thickness: 5 wun) Friction element cycle: 60 times/minute Friction element stroke: 70M Number of wears: 50,000 times The specific test method is the same as in Examples 13 to 24 above.

From the results in Tables 8 and 9 above, Examples 25 to 36 all passed the wear resistance test, while Comparative Example 13
-18, the amount of wear was 490 to 4580 mg and 150,000 times.

Note that the second invention can be applied not only to weather strips but also to members such as rubber packings and O-rings that require abrasion resistance and adhesion.

[Examples 37 to 46 and Comparative Examples 19 and 20] Next, the second
An example will be described in which the invention is embodied in a double-sided adhesive tape whose side surface is coated with a coating composition.

Side moldings are attached to the sides of the car body using double-sided adhesive tape. Assuming this case, a test piece was prepared as follows, and the adhesive area and tensile shear strength were measured.

(1) Preparation of test piece The coating composition shown in Table 10 was applied to the side edge of a double-sided adhesive tape, and then left for -1 week to be used for testing.

Then, a painted steel plate is glued to one side coated with an 8x expanded polyethylene foam adhesive, which is the base material of the double-sided adhesive tape, and the other side coated with adhesive is glued to a vinyl chloride resin plate. and used as a test piece. In addition, Comparative Example 19.2
0 was a test piece coated with the coating composition and 5 was not coated with the test piece.

(2) Measurement of adhesive area and tensile shear strength Each test piece was heated at room temperature of 23°C using gasoline (G) as a solvent,
After each sample was immersed in wax remover (W) for 1 hour, the tensile shear strength and the rate of decrease in adhesive area (%) were measured at a tensile speed of 50 mm/min. The results are also shown in Table-10.

Table 10 From the results in Table 10 above, in Examples 37 to 46, the adhesive area was secured at 90 to 94% of the initial state even when immersed in gasoline or wax remover, and the tensile shear strength was 8.0 to 8.0. It can be seen that it shows a high value of 8.4 kg/erl. On the other hand, in Comparative Example 19.20, the adhesive area decreased to 31.35% and the tensile shear strength was 1.
．． The value is as low as 5 kg/cnr.

Therefore, if a side molding is attached to the side surface of an automobile body using an adhesive tape with the paint composition of each example applied to the side edge, even if gasoline or wax remover adheres to the side edge of the adhesive tape, the side molding will be removed. The molding is held to the body with sufficient bonding strength.

The present invention can be applied to adhesive tapes used for chemical equipment to which solvents such as toluene and xylene may adhere, members to which kerosene may adhere, and the like.

[Effects of the Invention] The coating composition of the first invention has very good abrasion resistance on the surface of the resulting coating film, and also has excellent adhesion between the coating film and the object to be coated.

Furthermore, the coated body of the second invention exhibits excellent performance such as abrasion resistance and water repellency based on the characteristics of the coating composition of the first invention.

Claims (1)

[Claims] 1. Consisting of polyol, triethanolamine and polyisocyanate, the molar ratio of polyol:triethanolamine is 1:0.05 to 2.0, and hydroxyl group (
-OH): molar ratio of isocyanate group (-NCO) is 1
:1.5-7 for 100 parts by weight of polyurethane,
2 to 100 parts by weight of fluororesin, amino silicone (-NH_2): isocyanate group (-NCO)
A coating composition in which the molar ratio of is blended in an amount of 0.7 to 1.3:1. 2. A coated body obtained by applying the coating composition according to claim 1 onto the surface of a base material made of resin or rubber.