JPS60179469A - Paint composition - Google Patents

Abstract

PURPOSE:To provide a paint compsn. which gives electrostatic flocking products having excellent wearing properties in a high-temperature atmosphere or after thermal aging and weathering tests, consisting of a specified urethane prepolymer, a hardener and a polydimethylpolysiloxane. CONSTITUTION:A polyhydroxypolybutadiene (a) which has an average MW of 500-5,000 and wherein at least 98% of double bonds is hydrogenated, a polyol (b) (e.g. polypropylene oxide glycol) and a diisocyanate (c) (e.g. tolylene diisocyanate) are reacted together in an equivalent ratio of a+b>c to obtain a urethane prepolymer (A) contg. hydroxyl groups at its terminal. A hardener (B) composed of a diisocyanate or a urethane prepolymer contg. isocyanate groups at its terminal obtd. by reacting components (a), (b) and (c) in an equivalent ratio of (c)>(a) and/or (c) and a polydimethylpolysiloxane (C) are blended with component A.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating composition particularly suitable for use in electrostatic flocking products.

In recent years, electrostatic flocking products have been applied to various fields, but depending on the usage, various performances are required, and conventional flocking products do not necessarily fully meet these requirements. It wasn't there.

For example, to explain electrostatic flocking products applied to automobile windows, when supporting the window glass and window frame, especially when the glass can be slidably opened and closed, the frictional resistance Requires a glass holder made of low quality material. In automobiles, window frame rubber, i.e., a rubber or plastic weather strip, is used to fix the window glass and the window frame, and the sliding contact area with the sliding glass is used in the area where the glass slides. Glass run, which is electrostatically flocked with short fibers, is used.

Electrostatic flocking products used as glass runs in automobiles are
Compared to electrostatic flocking products used for interior decoration, daily necessities, and clothing, these products have excellent performance under harsh conditions, such as performance in high-temperature atmospheres, weather resistance, and heat resistance.

However, conventional products do not show sufficient performance, especially in terms of abrasion resistance after heat aging, abrasion resistance after weathering, and abrasion resistance in a high 1i'llt atmosphere.
Therefore, improving these performances has been a challenge in this technical field.

As a result of various studies, the present inventor focused on the fact that in electrostatic flocking products, the paint applied to the flocked areas is the biggest factor in determining the quality of their performance. We have succeeded in providing an inventive coating composition.

The coating composition of the present invention is characterized in that it uses a urethane prepolymer described below as a main ingredient, and a specific curing agent and polydimethylpolysiloxane are blended therein.

The coating composition of the present invention will be explained in detail below.

The urethane prepolymer used as the main ingredient in the coating composition of the present invention consists of polyhydroxypolybutadiene (a) in which 98% or more of double bonds are hydrogenated and a polyol (b).
and diisocyanate (c) (a) + (b)
><c) This is a urethane prepolymer having hydroxyl M at the end obtained by reacting at the ratio of c).

Here, polyhydroquine polybutadiene in which 98% or more of double bonds are hydrogenated will be explained. What is polyhydroxypolybutadiene?

It is a polybutadiene polymer having one or more hydroxyl groups, preferably 1.8 to 5.0 hydroxyl groups in one molecule, and the average molecular weight is usually 500 to 50,000, preferably 1.
000-2 D, 0 [I O The manufacturing method thereof is not specified, but various known methods can be employed.

For example, in the polymerization of butadiene, hydrogen peroxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, azohistochemicals having functional groups, such as β
'-azobis(β~cyano)-n-pronominol, δ
Radical polymerization may be carried out in a catalyst such as an alcohol, ketone, or ester using a radical polymerization initiator containing a hydroxyl group such as , δ-azobis(δ-n-a')-n-pentanol, or With a radical polymerization initiator such as azodicarphonic acid or its ester! 7 There is also a method in which polyhydrocarbons/butadiene is obtained by polymerizing in the same manner and then reducing the carboxyl group or ester moiety.

Alternatively, anionic polymerization may be performed using an alkali metal such as sodium or lithium or a complex of an alkali metal and a polycyclic aromatic compound as a catalyst, followed by functionalization with alkylene oxide, epichlorohydrin, or the like. Specifically, the catalyst used for anionic polymerization is a lithium complex such as lithium naphthalene complex, anthracene complex, or biphenyl complex, or 1,4-dialkali metal butane, 1,5
Examples include alkali metal hydrocarbons such as - dialkali metal bantan, 1,10-dialkali metal decane, 1,4-dialkali metal, and 1,1,4,4-tetraphenylbutane.

Furthermore, fc mechanism that allows such anionic polymerization to proceed smoothly
Hydrocarbon solvents such as , hexane, heptane, benzene, toluene, xylene, and cyclohexane are used.

However, when using an alkali metal as a catalyst, the above solvent and diethyl ether,
It is preferable to use a Lewis base such as ethyl zorobyl ether or ethyl phthyl ether in combination.

Polyhydroxybutadiene can be obtained by reacting the living polymer thus obtained with an epoxy compound according to a conventional method, and then treating it with a protic acid such as hydrochloric acid, sulfuric acid, or acetic acid.

Examples of compounds used here include polyethylene oxide, propylene oxide, petite oxide, cyclohexene oxide, styrene oxide,
Monoepoxy compounds such as phenyl glycidyl ether:
Polyepoxy compounds such as cricidyl ether of bisphenol A, vinylnochlorohexene dieboxide, butadiengo, -ggizide, dicyclonotadiene dieboxide, limonene dieboxide, bisepoxide of ethylene glycol: shrimp chlorohydrin, Ebibromohydrin, methylepichlorohydrin, and other compounds can be used. More preferred are polyepoxy compounds and haloepoxy compounds.

In the case of a monoepoxy compound, the amount used is preferably an equimolar ratio, particularly 2 or more molar ratio, to the polymer. At this time, it is considered that the epoxy compound is bonded to both ends of the living polymer IJ mer in a ring-opened manner, and the hydrogen atom of the ring-opened hydroxy group is substituted with an alkali metal.

On the other hand, when using a polyepoxy compound or a 10 epoxy compound, it is selected appropriately depending on the purpose of the resulting polymer, that is, the molecular weight and hydroxyl group of the polymer, but it is usually 05 to 2.0 mol based on the living polymer. A molar ratio of 0.6 to 1.0 is preferably used.

At this time, after the epoxy ring-opens, it is mainly the Living Hole IJ.
A IJ mer in which several molecules are bonded to each other through an epoxy compound having a hydroxyl group substituted with an alkali metal is obtained. Polyhydroquine and polybutadiene can also be obtained by reducing a polymer containing oxygen obtained by ozone dilution or other methods from a polybutadiene polymer that still has a high molecular weight.

Regarding the microstructure of the obtained polyhydroxypolybutadiene, depending on the manufacturing method, 1,2-bonds and 1,4-bonds
- Polymers with varying proportions of bonds are obtained. For example, the microstructure of polyhydroxypolybutadiene produced using a radical polymerization method has 5 to 3 cis-1,4 bonds.
0%, trans-1,4 bonds account for 50 to 80 percent, and 1,2 bonds account for 15 to 30%, resulting in a microstructure with usually a large number of 1,4 bonds. Even in the trench anionic polymerization method, 7r-dihydroxybolibutadiene having a large number of 1,4-bonds can be obtained by selecting the type of catalyst and solvent used.

The hydrogenated polyhydroxypolybutadiene used in the present invention is obtained by hydrogenating the two lf bonds in the main chain and/or side chain of the polyhydroquine polybutadiene produced in this way while retaining the hydroxyl group. obtained by doing. Nickel, cobalt, chromium, copper, palladium, platinum, rhodium, osmium, ruthenium, rhenium, etc. are commonly used as hydrogenation catalysts.
Preferred are nickel and ruthenium. These various metal catalysts are used as metals themselves, as heterogeneous catalysts supported on ID finger carriers, or as homogeneous catalysts with metals as soluble salts.

As the above carrier, carbon, alumina, silica, alumina silica, diatomaceous earth, barium carbonate, calcium carbonate, etc. are used. In this case, the amount of the metal supported on the carrier is usually in the range of 0.001 to 50% by weight, preferably 0.2 to 15% by weight.

Although polyhydroquine polybutadiene can be reacted with hydrogen as it is using the above-mentioned metal as a catalyst, a better hydrogenation reaction can be carried out by using a solvent.

This solvent includes aliphatic hydrocarbons, aromatic hydrocarbons,
Alcohol, ether, or a mixed solvent thereof can be used.

The amount of the above-mentioned catalyst used during hydrogenation varies depending on the type of catalyst, hydrogenation method, etc., but for example, when carrying out suspension polymerization using a ruthenium catalyst, the ratio of ruthenium to polyhydroxypolybutadiene is , o, oi~1
．． It is used in the range of 0.00 weight. Reaction dryness is 20
~150°C is preferred.

If the reaction temperature becomes high, the hydrogenation rate can be increased, but this is not preferable because the cleavage of hydroxyl groups becomes non-negligible. The hydrogen used may be at normal pressure, a flow line or high pressure, and any reaction form such as a fixed bed suspension system may be employed for the hydrogenation reaction.

The hydrogenation conditions described above hydrogenate the double bonds in the main chain and/or side chains in polyhydroxy and +O ribtannins, but in the case of those used in the composition of the present invention, It is necessary that the double bonds in the IFO 17mer be almost completely hydrogenated, preferably 98% or more of the double bonds in the IFO 17mer before hydrogenation, preferably 1.
It is necessary that the hydrogenation be carried out to an extent that substantially no double bonds remain, preferably 99% or more.

The urethane prepolymer and curing agent to which polydimethylpolysiloxane is blended in the coating composition of the present invention are as follows.

(1) The above-mentioned polyhydroxypolybutadiene (a) in which 98% or more of double bonds are hydrogenated, polyol (b), and diisocyanate (cl) are prepared at our museum, (a) + (b)
>Urethane pred51J polymer having a hydroxyl group at the terminal obtained by reacting at the ratio of (C) =? = agent,
To this, an equivalent amount (c) of polyhydroxypolybutadiene (a) and/or polyol (b) in which 98% or more of double bonds are hydrogenated and diisocyanate (C)>
A urethane prepolymer having an incyanate group at the end obtained by reacting in the ratio of (a) and (b) is blended as a curing agent.

(2) Polyhydroxypolybutadiene (a) in which the double bonds described above have been hydrogenated 98 times or more and polyol (
b) and diisocyanate (C) in a ratio of (a) to (b) > (c) to form a urethane prepolymer having a hydroxyl group at the end + a main ingredient, and diisocyanate as a curing agent. Compounded as.

The above-mentioned polyols include polypropylene oxide glycol, polytetramethylene oxide glycol, polyethylene-butylene adipate, polyethylene azide, polyethylene azizute, polydiethylene adipate, acrylic polyol, 1.6-hexanediol adipate, etc. Illustrated. +OIJol, and the above-mentioned diisocyanate is tolylene diisocyanate, 4
・Diisocyanates exemplified by 4'-phenyl diisocyanate, 4.4'-diphenylmethane diisocyanate, dianisidine diisocyanate, tridene diisocyanate, rameryl diiso/anate, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate, quinoles diisocyanate, etc. be.

The coating composition of the present invention is characterized in that polydimethyl and I-serisiloxane are blended into the urethane prepolymer base and curing agent as described above.

The coating composition of the present invention is particularly excellent in abrasion properties after heat aging, abrasion properties after weathering, and abrasion properties in a high-temperature atmosphere, and -
It should be noted that in electrostatic flocking products, these performances are significantly demonstrated when applied to the flocked areas. If this is used in a glass run for automobiles, a product with extremely excellent performance can be obtained.

It can be seen that the performance of the coating composition of the present invention is extremely excellent from the results of product tests in Examples and Comparative Examples described below.

Hereinafter, the present invention will be explained with reference to examples. However, the present invention is not limited to electrostatic flocking products shown in the following examples, but can also be applied to products of various shapes made of various materials such as rubber, plastic, metal, textiles, and ceramics. It will be obvious to those skilled in the art that it can be used as a coating composition for flocked products or other products.

Details of the wear tests conducted on the following examples and grain ratio examples are as described below.

Testing machine = KI type abrasion test Test conditions: Abrasion element Glass (thickness: 5mm) Load: 3 to 30% abrasion element cycle: 60 times/min Abrasion element stroke: 145mm Test method: The sample was mounted on the above testing machine under the above conditions. Rub the electrostatic flocking product with it.

In addition, various types of abrasion properties in the abrasion test are as follows.

(2) Abrasion after heat aging After the samples of rhinoceros J7 were left in a hot-air dryer at 80°C for 200 hours, some samples were rubbed by the above-mentioned testing machine.

■ IY resistance after sunshine weather meter treatment Two carbon arc illusions were used. Place the friction sample on the weatherometer After being exposed for 200 hours, it was tested in the above test machine. Yields are subject to friction.

■ Abrasion resistance in 60℃ atmosphere Take the sample before aging and use it in the above testing machine. Friction is performed while maintaining the atmosphere at 60℃. do.

Example 1 A mixture of dimethyl sulfo oxide was reacted at 8DC for 6 hours in dry nitrogen gas to produce a urethane prepolymer having hydroxyl groups at the terminals.

A mixture of 168 parts of dimethylformamide was reacted at 80° C. for 3 hours in dry nitrogen gas to produce a urethane prepolymer having incyanate groups at the ends.

(c) Mix 260 parts of (a) and 100 parts of (b) to make one V! 7 mol'ti. ff: Got it.

(a) A coating composition was prepared by adding 10 parts of polydimethylpolysiloxane (100,000 cst) and 6 parts of carbon black to 100 parts of the bath solution obtained in (C).

(e) This coating composition was applied to the flocked surface of an electrostatic flocked product and dried at 80° C. for 60 minutes.

(f) The same operation as in (e) was performed using only the urethane polymer of (C) above to obtain a product as a comparative example (ratio example 1).

Example 2 (a'l Polyhydroquinopolybutadiene (molecular weight cotton 2000) in which 98% or more of double bonds are hydrogenated)
200 parts, polypropylene oxide/. −． Enigellicol (molecular weight approx. 2000) 2000 parts, 4.4'-diphenylmethane diiso/anate 25 parts, dimethylformamin + "i o o o parts fa: 8 3 at 0°C
11) A urethane prepolymer was synthesized by reacting in dry chino gas.

26 parts of 1,5-naphthalene diisocyanate was mixed into this urethane prepolymer as a curing agent.

(b) A coating composition was prepared by adding glass/methylpolysiloxane and carbon black to 100 parts of the mixture obtained in step (a) in the same manner as in Example 1(d).

(C) This coating composition was applied to an electrostatic flocked product in the same manner as in Example 1(e).

(d) Only the mixture obtained in (a) above is published. A: The abrasion test results of the above Example and Comparative Example products are shown in a table.

(Unit: times) Note: The number of times listed is based on the original exposure.

Claims (1)

[Claims] (1) Polyhydroxypolybutadiene (a) in which 98% or more of double bonds are hydrogenated, polyol (b), and diisocyanate (C) are mixed in equivalent amounts (a) + (b) >
The base material is a urethane prepolymer having a hydroxyl group at the end obtained by reacting at the ratio of (c), and
Polyhydroxypolybutadiene (a) and/or polyol (b) in which 98% or more of double bonds are hydrogenated
and diisocyanate-') (c) and equivalent (c) > (
It is characterized by blending as a curing agent a urethane prepolymer or diisocyanate having an isocyanate group at the end obtained by reacting in the ratio of a) and (or) (b), and further blending polydimethylpolysiloxane. Paint composition.