JP2893301B2 - Thermoplastic elastomer paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-coat paint used for surface coating of a thermoplastic resin elastomer molded article.

[0002]

2. Description of the Related Art Conventionally, the coating of thermoplastic resin elastomer resin products is roughly classified into one-pack type and two-pack type.
There is a liquid type, and particularly for automobile interior parts, the following composition-containing paints are known for each of the one-part type and the two-part type. In the following, two one-liquid types are illustrated and shown in Table 5, and four two-liquid types are illustrated in Table 6 respectively.

[0003]

[Table 5]

[0004]

[Table 6]

[0005]

However, such a conventional coating material is required for surface coating of a thermoplastic resin elastomer molded article in both the one-pack type and the two-pack type. There was a problem in the adhesion property in the pretreatment and primerless, and the coating performance and design effect (texture reproducibility, soft touch property) in a thin film (10 μm) were lacking.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and has been developed as a coating material for a thermoplastic elastomer molded article, particularly a thermoplastic elastomer elastomer molded article for an automobile interior, and has a coating property, a coating performance, a design property, and the like. The aim is to provide a coating for thermoplastic elastomer moldings that has both coating workability and coating appearance.

[0007]

Means for Solving the Problems As a result of intensive studies, the present invention has solved the above-mentioned problems by providing a coating for a thermoplastic elastomer molded article having the following characteristics. The one-coat paint for a thermoplastic elastomer molded part according to the first invention of the present application is an optional paint selected from the group consisting of a) isophorone diisocyanate, hexamethylene diisocyanate and hydrogenated diphenyl methane diisocyanate as main ingredients. A hydroxyl group-containing urethane polyol obtained by reacting one or several members of an isocyanate component with a polycarbonate polyol component (hereinafter referred to as the urethane polyol);
b) An alcohol-modified silicone is blended as an essential component. The resin component of the curing agent of the paint includes: c) an isocyanate group-containing addition polymer obtained by reacting an isocyanate component of an aliphatic diisocyanate with a polyester polyol component; d) a polymer of an aliphatic diisocyanate; At least one of which is a main component. Further, the second invention of the present application provides a one-coat paint for thermoplastic elastomer molded parts, in which a polyester polyol is blended in addition to the above components a) and b) as a main component of the paint.

For example, a hydroxyl group-containing urethane polyol addition polymer obtained by reacting an isocyanate component of isophorone diisocyanate as a main component with a polycarbonate polyol component has the following properties and characteristics. Properties Molecular weight 15000 to 20000 OH% 3% or less Acid value 1 or more General formula Basic skeleton

[0009]

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Elongation / tensile strength 400-500% / 300
４００400 kg / cm ² Features Large binding energy, balanced elongation / tensile strength, strong coating film. Moreover, it has excellent adhesion.

[0011] It should be noted that even if two or three kinds of isophorone diisocyanate, hexamethylene diisocyanate and hydrogenated diphenylmethane diisocyanate are used, or even if hexamethylene diisocyanate or hydrogenated diphenylmethane diisocyanate alone is used, the molecular weight is large and the binding energy is high. Is equivalent to isophorone diisocyanate.

It is preferable that the main component is mixed in the following range. Mixing of main component (unit: parts by weight) Urethane polyol 10-20 Polyester polyol 5-20 Carbon black 1-4 Gloss modifier 2-5 Pigment dispersant 0.1-1.5 Methyl ethyl ketone 17-30 Cyclohexanone 17-30 Xylene 5-11 Cellsolve acetate 1-3 Lightfast agent 0.3-3

Further, by blending an alcohol-modified silicone (methylhydrogenpolysiloxane) as an essential component of the main component of the paint according to the present invention, it is possible to enhance the adhesion to a thermoplastic elastomer product. is there. It is preferable that the range of the blending ratio of the modified silicone is 1 to 3 parts by weight (the blending unit is represented by part by weight).

Further, a design property can be imparted by mixing a polyethylene wax as a surface conditioner at a ratio of 2 to 5 with the above-mentioned composition.

On the other hand, as a main component of the curing agent, an isocyanate group-containing addition polymer obtained by reacting an isocyanate component of an aliphatic diisocyanate with a polyester polyol component can be used. An addition polymer of a diisocyanate and a polyester polyol can be mentioned. Also,
As a main component of the curing agent, a polymer of an aliphatic diisocyanate can be used. An example is a burette adduct of an aliphatic diisocyanate such as hexamethylene diisocyanate.

The isocyanate group-containing addition polymer or the aliphatic diisocyanate constituting the polymer is not limited to the above hexamethylene diisocyanate, but may be other aliphatic diisocyanates such as xylene diisocyanate. It is also possible to use a systemic diisocyanate.

Further, by using a thinner for diluting containing a mixture of a ketone, an ester, an aromatic hydrocarbon and a glycol as a main component, adhesion, coating performance, designability, coating workability and coating appearance Can be further improved.

[0018]

According to the present invention, the main ingredient is isophorone diisocyanate, hexamethylene diisocyanate and hydrogenated diphenylmethane diisocyanate.
Since the main component is a hydroxyl group-containing urethane polyol obtained by reacting an arbitrary one or several member isocyanate component selected from the group with a polycarbonate polyol component, firstly, the bonding energy of the polymer main bond is Second, its molecular weight is also large (10.00
0 or more), and thirdly, the strength of the coating film, that is, elongation (10
(0% or more) and tensile strength (200 kg / cm ² or more). Therefore, it was possible to follow the deformation of the molded article of the thermoplastic elastomer, obtain excellent coating film performance with a thin film, and reproducibility of the grain shape of the molded article. Further, by modifying the resin component of the main agent with methylhydrogenpolysiloxane, it was possible to obtain better adhesion to the molded article of the thermoplastic elastomer. In addition, at the same time, the resin component of the curing agent together with the resin component of the main agent is an isocyanate group-containing addition polymer obtained by reacting the isocyanate component of the aliphatic diisocyanate with the polyester polyol component or the polymerization of the aliphatic diisocyanate. Because of the main component, stability (reliability) of the target coating film in terms of performance, workability, drying properties, appearance, design, etc.
Can be significantly improved.

In the second invention of the present application, the first invention of the present application
In the paint according to the invention of the present invention, since the main component of this paint is a blend of polyester polyol in addition to the above components, to give the paint an appropriate elongation, so that the above effects can be more reliably exerted. It was done.

As described above, the paints according to the two inventions of the present application enable a thin film (10 μm) to enable the coating properties and design required for a paint for a thermoplastic elastomer molded article, and further eliminate the pretreatment and the primer. Because it became possible, it became possible to use it for various kinds of paintings, such as for interiors of automobiles. In addition, since colorization can be easily performed, an excellent design effect such as obtaining a sense of unity with other molded products can be obtained.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described. First, after adding the effect agent to the main ingredient and mixing well with stirring,
Add the diluted thinner and stir to adjust the paint (viscosity 1
1-13 seconds, non-volatile content 13-15%). With respect to the paints of Examples 1 to 4 obtained in this way, the mixing examples of the main agent, the curing agent, and the diluted thinner are shown in Table 1 below.

[0022]

[Table 1]

Each of Examples 1 to 4 was blended under the conditions shown in Table 3 below, and Comparative Examples 1 to 4 of the blending examples shown in Table 2 below were blended under the conditions shown in Table 4 below. Mix and paint.

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

In this coating, the adjusted paint is applied to an air spray gun (Iwata Weider 71, caliber 0.8 to 1.3 m /
m), the air pressure is 3 to 5 kg / cm ² , and the discharge rate is 60 to
Painting is performed on the surface of the molded article to a predetermined thickness under the condition of 100 cc / min. After the coating, it is left at room temperature for 2 to 5 minutes, and then dried at 60 to 80 ° C for 20 to 40 minutes. Thereby, a film can be formed on the surface of the molded product.

As a result, the performance value and the performance evaluation of the coating film obtained in this example are shown in Table 3, and the performance value and the performance evaluation of the coating film obtained in the comparative example are shown in Table 4. As described above, as shown in Tables 3 and 4, the coating films of the respective examples had higher adhesiveness than the comparative examples.
It was confirmed that the coating film performance and appearance (design) were excellent.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-240577 (JP, A) JP-A-3-159709 (JP, A) JP-A-3-21675 (JP, A) JP-A-3-21675 41173 (JP, A) JP-A-5-51555 (JP, A) JP-A-59-18733 (JP, A) JP-A-58-111823 (JP, A) JP-A-58-5370 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) C09D 175/00-175/16 C08G 18/00-18/87

Claims (2)

(57) [Claims] 1. A paint which can be used as a one-coat paint which does not require a pretreatment and a primer on a molded article using a thermoplastic elastomer, wherein the main ingredients of the paint are the following essential components a) and b) Wherein the resin component of the curing agent of the coating composition contains at least one of the following c) and d) as a main component. paint. a) A hydroxyl group-containing urethane polyol obtained by reacting an arbitrary one or several member isocyanate component selected from a group consisting of isophorone diisocyanate, hexamethylene diisocyanate and hydrogenated diphenylmethane diisocyanate with a polycarbonate polyol component. b) alcohol-modified silicone. c) An isocyanate group-containing addition polymer obtained by reacting an isocyanate component of an aliphatic diisocyanate with a polyester polyol component. d) Polymer of aliphatic diisocyanate. 2. A thermoplastic elastomer molded part according to claim 1, wherein the main component of the coating is a mixture of a polyester polyol in addition to the components a) and b). 1-coat paint.