JPS6024821B2 - paint composition - Google Patents

Description

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

In recent years, electrostatic flocking products have been applied to various types of hair, but depending on the usage, various performances are required.
Conventional flocked products have not always fully met these requirements.

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, that is, a rubber or plastic weather strip, is used to secure the window glass and window frame, and a weather strip made of rubber or plastic is used to secure the window glass and the window frame. Glass run, which is electrostatically flocked short fibers, is used. Electrostatic flocking products used as glass runs for automobiles are particularly difficult to handle under harsh conditions such as performance in high temperature atmospheres, weather resistance, and heat resistance compared to electrostatic flocking products used for interior decoration, daily necessities, and clothing. Various performances are required below. 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 high-temperature atmospheres. Improvement has been a challenge in this field of technology.

As a result of various researches, the present invention is based on electrostatic flocking products.
Focusing on the fact that the paint applied to the flocked areas is the biggest factor in determining the quality of their performance, the inventors sought to improve the paint and succeeded in providing the paint composition of the present invention. The coating composition of the present invention is characterized by containing silicone in the urethane polymer described below.

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

The urethane polymer in the coating composition of the present invention is obtained by reacting polyhydroxybolibutadiene (a) in which 98% or more of double bonds are hydrogenated, one or more polyether-based or polyester-based diols (b), and diisocyanate (c). This is a urethane polymer having an isocyanate group or a hydroxyl group at the end obtained by reacting a urethane polymer having an isocyanate group at the end with a low molecular weight diol. Here, polyhydroxybutadiene hydrogenated with a double bond concentration of % or more will be explained. This polyhydroxypolybutadiene has one or more double bonds in one molecule, preferably 1.8 to 5. It is a polybutadiene polymer having a hard hydroxyl group, and the average molecular weight is usually 500 to 50,000, preferably 1,000.
~20,000, and 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, azobis-based compounds having functional groups, e.g.
1-azobis(8-cyano)-n-propanol, 8,
Radical polymerization may be carried out in a catalyst such as alcohol, ketone, or ester using a radical polymerization initiator containing a hydroxyl group such as 6-azobis(6-cyano)-bentanol, or aliphatic azodicarboxylic acid or its ester may be used. There is also a method in which polyhydroxypolybutadiene is obtained by similarly polymerizing with a radical polymerization initiator 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 catalysts used for anionic polymerization include lithium bodies such as naphthalene bodies, anthracene bodies, biphenyl rust bodies, 1,4-dialkali metal butane, 1,5-dialkali metal pentane, 1,10 - dialkali metal decane, 1,4-dialkali metal, 1,1,
Mention may be made of dialkali metal hydrocarbons such as 4,4-tetraphenylbutane. Furthermore, in order to smoothly proceed with such anionic polymerization, hexane, heptane, benzene,
Hydrocarbon solvents such as toluene, xylene, and cyclohexane are used.

However, when an alkali metal is used as a catalyst, it is preferable to use the above solvent together with a Lewis base such as diethyl ether, dipropyl ether, ethylpropyl ether, ethyl butyl ether. Polyhydroxybutadiene can be obtained by reacting the Bing 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.

The epoxy compounds used here include monoepoxy compounds such as ethylene oxide, propylene oxide, butylene oxide, dichlorohexene oxide, styrene oxide, and phenyl glycidyl ether; glycidyl ether of bisphenol A, vinyl cyclohexene dieboxide, butadiene oxide; Epoxide, polyepoxy compounds such as dicyclobentadiene diepoxide, limonene diepoxide, and bisepoxide of ethylene glycol: EPIC.

Haloepoxy compounds such as ruhydrin, epipromhydrin, methylepiclorufdrin 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 thought that the epoxy compound is bonded to both ends of the living polymer in a cyclic manner, and the hydrogen atoms of the hydroxyl groups in the cyclic bond are substituted with an alkali metal. On the other hand, when using a polyepoxy compound or a haloepoxy compound, it is selected appropriately depending on the use of the obtained polymer, that is, the molecular weight and number of hydroxyl groups of the polymer, but usually 0.5 to
A molar ratio of 2.0, preferably 0.6 to 1.0 is used.

At this time, after the epoxy is ring-opened, living polymers are mainly bonded to each other, and a polymer in which several molecules are bonded via an epoxy compound having a hydroxyl group substituted with an alkali metal is obtained.

Polyhydroxy and polybutadiene can also be obtained by reducing a high molecular weight polybutadiene polymer obtained by ozonolysis or other methods containing oxygen. Regarding the microstructure of the obtained polyhydroxypolyptadiene, polymers having various proportions of 1,2-bonds and 1,4-bonds can be obtained depending on the manufacturing method. For example, the microstructure of polyhydroxypolybutadiene produced using a radical polymerization method has 5 to 30% of cis-1,4 bonds and 5% of trans-1,4 bonds.
0-80%, 1,2 bonds account for 15-30%, usually 1
, 4, resulting in a microstructure with many bonds. Furthermore, in the anionic polymerization method, it is possible to obtain polyhydroxybolibutadiene with a large number of 1,4 combinations by selecting the type of catalyst and solvent used. The hydrogenated polyhydroxypolybutadiene used in the present invention is obtained by hydrogenating the double bonds in the main chain and/or side chains of the polyhydroxypolybutadiene produced in this way while retaining the hydroxyl groups. obtained by doing. As the hydrogenation catalyst, nickel, cobalt, chromium, copper, palladium, platinum, rhodium, osmium, ruthenium, rhenium, etc. are generally used, with nickel and ruthenium being preferred. These various metal catalysts are metals themselves,
Alternatively, it is used as a heterogeneous catalyst supported on a carrier, or as a homogeneous catalyst with a metal as a soluble salt. As the above-mentioned carrier, carbon, alumina, silica, alumina/silica, carbon dioxide, barium carbonate, calcium carbonate, etc. are used.

In this case, the amount of the metal supported on the carrier is usually 0.01 to 5
% by weight, preferably from 0.2 to 15% by weight. Although polyhydroxybolibutadiene can be reacted as it is with hydrogen using the above-mentioned metal as a catalyst, a better hydrogenation reaction can be carried out by using a solvent. As this solvent, aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, fables, or mixed solvents 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 polyhydroxypolyptadiene is , used in a range of 0.01 to 1.0% by weight. The reaction temperature is preferably 20 to 150°C. 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 used at normal pressure, in a flow system or at high pressure, and the hydrogenation reaction may be carried out in any reaction form such as a fixed bed suspension system. Under the above-mentioned hydrogenation conditions, the double bonds in the main chain and/or side chain in polyhydroxypolybutadiene are hydrogenated, but in the composition of the present invention, the double bonds in the polymer are It is necessary to hydrogenate almost completely, and hydrogenation is performed until at least 98%, preferably at least 99%, of the double bonds in the polymer before hydrogenation, and more preferably until substantially no double bonds remain. It is necessary to do so.

The polyether-based or polyester-based diol used in the present invention is exemplified by polypropylene oxide glycol, polytetramethylene oxide glycol, polyethylene-butylene adipate, polyethylene adipate, polybutylene adipate, polyethylene adipate, etc. Examples of diisocyanates include toluene diisocyanate, 4,4'-phenyl diisocyanate, 4,4'-phenylmethane diisocyanate, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate, xylene diisocyanate, etc. It is a diisocyanate.

Moreover, low molecular weight diols are diols exemplified by ethylene glycol, propylene glycol, butylene glycol, bentanediol, hexanediol, octanediol, diethylene glycol, triethylene glycol, neobentyl glycol, dipropylene glycol, and the like. The urethane polymer used in the present invention is obtained by reacting polyhydroxypolybutadiene a, polyether-based or polyester-based diol b, and diisocyanate c as described above as raw materials at 80 qo for 3 hours in dry nitrogen gas, for example, A urethane prepolymer having an isocyanate group at the end is produced, and further an organic solvent is added to this urethane prepolymer,
A urethane polymer having an isocyanate group or a hydroxyl group at the end is obtained by adding a low-molecular diol to this and carrying out a chain extension reaction at 80C for 2 minutes in dry nitrogen gas, for example.

The coating composition of the present invention is characterized in that this urethane polymer is blended with polydimethylpolysiloxane.

The coating composition of the present invention is particularly excellent in abrasion resistance after heat aging, abrasion resistance after weathering, and abrasion resistance in high-temperature atmospheres.It should be noted that when applied to the flocked areas of electrostatic flocking products, These performances are significantly demonstrated.

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 for the following Examples and Comparative Examples are as described below.

Testing machine: KI type abrasion test Test conditions Wear element: Glass (5 skin thickness) Load: 3 kg Wear element cycle: 6 sub/min wear element stroke: 145 legs Test method: The sample was mounted on the above testing machine and electrostatically charged under the above conditions. Rub the flocked surface.

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

■ Abrasion after heat aging treatment After leaving the sample for friction in a hot air dryer for 20 hours at 8 x ○, it was attached to the above testing machine and rubbed.

(2) After exposing the friction sample to a Weatherometer using two abrasive carbon arc lamps after Sunshine Weather Treatment for 20 hours, it was attached to the above testing machine and rubbed. (2) Abrasion in 6000°C atmosphere The sample before aging was attached to the above testing machine and rubbed in a 60°C atmosphere.

Example {a' 200 parts of polyhydroxypolyptadiene (molecular weight approximately 2000) in which 98% or more of double bonds are hydrogenated,
Polypropylene oxide glycol (molecular weight approximately 2000
) 547 parts, polyethylene adibate (molecular weight approximately 200
0) A mixture of 336 parts of 4,4'-diphenylmethane diisocyanate, 560 parts of trichlorethylene and 168 parts of trichlorethylene was reacted at 80°C for 3 hours in dry nitrogen gas, and then 14 parts of 1,6-hexanediol was reacted. , 1322 parts of dimethylformamide was added and reacted at 80 oo for 20 minutes in dry nitrogen to synthesize a urethane polymer.

[b' A coating composition was prepared by adding 10 parts of this urethane polymer, 1 part of polydimethylpolysiloxane (10-way CST), and 3 parts of carbon black.

{c' The above coating composition was applied to the flocked surface of the electrostatic flocking product and dried at 80° C. for 30 minutes.

Side: A comparative example product was obtained by carrying out the operation 'c} using only the above urethane polymer.

The abrasion test results of the products of the above examples and comparative examples are shown in a table.

(Unit: times) Note: In both cases, base material exposure is based on the number of times stated.

Claims (1)

[Claims] 1 Urethane preform having an isocyanate group at the terminal obtained by reacting polyhydroxypolybutadiene a with hydrogenated double bonds of 98% or more, one or more types of polyether-based or polyester-based diols b, and diisocyanate c. A coating composition characterized in that a polydimethylpolysiloxane is blended into a urethane polymer having an isocyanate group or a hydroxyl group at the end obtained by reacting a polymer with a low-molecular-weight diol.