JPH03101911A - Manufacture of leather tone multi-layer structure - Google Patents

Abstract

PURPOSE:To enable monolithic molding of a leather tone multi-layer structure having favorable hand and high-class appearance so that physical properties of a coating such as wear strength is not deteriorated, by a method wherein the coating containing leather powder is molded intergally on the surface of synthetic resin by making use of a porous mold. CONSTITUTION:Paint containing leather powder is applied to the inside of a porous metal, which is dried, solidified and a coating is formed. In this instance, when a mold is not porous, a coating surface becomes a state of a mirror surface, but does not become a leather tone. The paint to be applied to the inside of the porous mold contains the leather powder, and a particle diameter of the leather powder is made not exceeding 100mum. When the particle diameter exceeds 100mum, a multi-layer structure to be obtained is inferior in soft tone. It is preferably that the particle diameter of the leather powder is not exceeding 30mum to obtain favroable touch feeling. The leather powder in the paint is made into 5-50wt.%. When the same is less than 3wt.%, the touch feeling of the leather tone of the multi-layer structure to be obtained is insufficient and when the same exceeds 50wt.%, physical properties of the coating such as wear strength is deteriorated. Then synthetic resin is cast on the coating, laminated on the obtained coating and integrated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a leather-like multilayer structure used for automobile interiors, various miscellaneous goods, and the like.

[Conventional technology]

BACKGROUND ART Conventionally, urethane resins and other composite resins formed by vacuum molding, injection molding, etc. have been used for automobile steering wheels, instrument panels, and various miscellaneous goods. However, since the surface of these resins is in contact with the mold surface, the surface properties of the mold are transferred.
The problem is that the mirror surface has a high gloss and gives the impression of being cheap, lacking a sense of luxury. It also lacks a leather-like touch feel. Therefore, it was desired to make the resin surface matte and improve the touch feel. Therefore, there is a method of painting urethane paint on the surface of synthetic resin to improve surface properties. Urethane paints include one-component lacquer types and two-component urethane, which consists of two components: polyol and isocyanate. In order to improve the matting effect on the surface of any paint, it is necessary to add a large amount of a matting agent such as silica to the paint, but adding a large amount of matting agent can affect the physical properties of the paint film such as abrasion strength. There is a problem with the decline. Furthermore, even if conventional paints contain silica, they have a sticky feel and do not have an excellent feel to the touch.

[Problem to be solved by the invention]

The present invention is an efficient way to form a leather-like multilayered structure with a surface appearance and touch feeling equivalent to that of leather, and a luxurious feel with a good texture, without deteriorating the physical properties of the coating film such as abrasion strength. The aim is to provide a manufacturing method that is easy to use.

[Means to solve the problem]

The inventors of the present invention have conducted extensive research in order to solve the above problem, and as a result, the objective was achieved by integrally forming a coating film containing leather powder on the resin surface using a porous mold. After discovering that this is true, I have come to completely disclaim this invention. That is, in the present invention, leather powder with a particle size of 100 μm or less is
A leather-like multilayer structure characterized in that a paint containing ~50% by weight is applied to the inner surface of a porous mold, dried and solidified to form a paint film, and a synthetic resin is injected and laminated on the paint film. It provides a manufacturing method. In the present invention, first, a paint containing leather powder is applied to the inner surface of a porous mold and dried to solidify to form a coating film.

Porous molds are porous molds whose inner surfaces can be painted with paint containing leather powder and injected with resin, depending on the shape of the structure to be obtained. is used. If the mold is not porous, the mirror-like cleanliness of the mold surface will be transferred to the paint film surface due to the transferability of the surface properties of the mold to the paint film, and the paint film surface will also have a mirror-like gloss. It has a high opacity and does not have a leather-like appearance. Here, the size of the pores is preferably 100 tIm or less. If it exceeds 100 am, the porous material will become clogged with leather powder, etc., resulting in poor workability. Specifically, for example, an electroforming mold such as a leather grain bolus electroforming mold having a skin grain pattern is preferably used.

The paint applied to the inner surface of this porous mold contains leather powder. The particle size of the leather powder is 100 prn or less. 1
If it exceeds 00 μm, the resulting multilayer structure will have poor soft feel. In order to obtain a good touch feeling, the particle size of leather powder should be 30
It is preferably less than grn. The leather powder in the paint should be 5 to 50% by weight. If it is less than 5% by weight, the resulting multilayer structure will lack a leather-like touch feel, and if it exceeds 50% by weight, the physical properties of the coating film such as abrasion strength will deteriorate. Particularly preferred is 10 to 20% by weight. When a solvent is contained in the coating material, the solid content ratio of the leather powder after solvent evaporation and drying is preferably 20 to 40% by weight.

The paint containing the leather powder is preferably a urethane paint, and the urethane paint is applied to the inner surface of the porous mold and solidified by drying and curing to form a coating film. Urethane paints include two-component urethane paints and one-component lacquer types.

A two-component urethane coating solution is one that is composed of two components: polyol and isocyanate as a curing agent.

Specifically, for example, a two-component special urethane paint containing condensed polyester polyol and isocyanate as a curing agent is preferable. Examples of the isocyanate curing agent include hexamethylene diisocyanate-based compounds (eg, HMD I isocyanate). The amount of curing agent blended is preferably 10 to 20 parts per 100 parts (parts by weight, same hereinafter) of the leather powder-containing polyol. Additionally, additives may be added to the urethane paint as necessary. As the additive, for example, a curing accelerator such as a tertiary amine compound or an organometallic compound is preferably used. The amount of the curing accelerator added is preferably 3 to 20 parts, particularly preferably 10 to 20 parts, based on 100 parts of the leather powder-containing polyol. If the amount added is small, the curing time will be long, and if the amount added is large, the pot life will be extremely short.

Further, the urethane paint is preferably diluted with a solvent such as thinner to adjust the viscosity.

In particular, it is preferable to use a thinner because the curing time of the coating film can be shortened and productivity can be improved. The amount of solvent such as thinner is 5 parts per 100 parts of polyol containing leather powder.
~20 parts is preferred.

Additionally, a one-component lacquer type can be used to shorten the working time. A spray method is preferably used to form a coating film by applying a coating containing leather powder to the inner surface of a porous mold and drying and solidifying it. It is preferable that the coating film has a thickness of 3 to 30 μm after drying and solidification of the solvent. Particularly preferably 5 to 20μ
It is m. If the thickness is less than 3 μm, the leather-like touch feeling is insufficient. If it exceeds 30 μm, physical properties such as abrasion strength of the coating film will deteriorate, and blisters, wrinkles, peeling, etc. of the coating film will occur, resulting in poor appearance. Moreover, the drying and solidifying time for forming a coating film becomes long, resulting in poor productivity.

Drying and solidifying to form a coating takes 2 minutes at 45-75°C.
Preferably, this is carried out for 60 minutes. If the temperature is lower than 45°C, the leather powder-containing paint in the coating may not solidify.

When the temperature exceeds 75°C, the foaming rate of the urethane resin increases, resulting in poor appearance and extremely poor mold releasability. Further, when a curing accelerator or thinner is added to the urethane paint, by adjusting the amount of these added, it is possible to sufficiently dry and harden and solidify in 2 to 10 minutes, which is preferable because productivity is improved. Heating of the coating film for drying and solidification can be suitably carried out by controlling the temperature of the mold.

The drying and solidifying conditions are W! It may be determined appropriately depending on the thickness of A, the amount of hardening accelerator, thinner, etc. to be added.

Next, a synthetic resin is injected and laminated onto the obtained coating film.

Polyurethane and polyvinyl chloride (PVC) can be suitably used as the resin for injection lamination.

Polyurethane is particularly preferred from the viewpoint of a leather-like touch.

As a method for injecting and laminating the above-mentioned resin into a porous mold whose inner surface is coated with a paint film containing leather powder, a method such as injection molding is preferably used.

By this injection lamination, the synthetic resin is integrally molded on the coating film of the leather powder-containing paint. This is a method generally called in-mold precept. By integrally molding, a multilayer structure can be obtained that has good coating properties such as abrasion strength and does not require a primer for adhesion between the leather-containing paint and the resin. The amount of synthetic resin to be injected may be appropriately determined depending on the shape of the desired multilayer structure, etc., and the conditions for drying and curing may be determined accordingly.

Furthermore, this molded article can be removed from the porous mold to obtain a desired leather-like multilayer structure.

FIGS. 1(a) to 1(a) are cross-sectional explanatory views showing an example of the outline of the method for manufacturing the leather-like multilayer structure of the present invention.

The inner surface of the porous mold 1 having a concave cross section as shown in FIG.
As shown in Figure (b), paint 2 containing leather powder is applied, dried and solidified to form a paint film. Onto this coating film, as shown in FIG. 1(C), the Gakai resin 3 is injected and laminated. Next, the shaped article is taken out from the porous mold 1 to obtain the desired leather-like multilayer structure 4.

The leather-like multilayer structure obtained according to the present invention has a coating film containing leather powder on the surface, and has an appearance and touch feeling comparable to that of leather, and has a luxurious feel. Moreover, since the leather powder-containing coating film and the resin are integrally formed, the coating film properties such as abrasion strength are also good.

[Example] Examples 1 to 3 As a porous mold, a rectangular mold with an inner diameter of 20 Cl+ on each side and a micro-bolus mold with a pore diameter of 5 μm was used after being vacuumed in advance with a logic seal type vacuum pump. In Examples 1 to 3, a leather powder-containing urethane paint having the formulation shown in Table 1 was applied to the inner surface of the porous mold, and dried and cured under the conditions shown in Table 1 to obtain the thickness shown in Table 1. A coating film was obtained. The formulation used here was as follows.

Main agent: Leather powder-containing polyol polyester Matillo ■ (manufactured by Idemitsu Petrochemical ■) Hardening agent: Matthiguchi B liquid (manufactured by Idemitsu Petrochemical ■) Additive: Mattillo additive (manufactured by Idemitsu Petrochemical ■) Thinner: Storon 2500 Thinner (manufactured by Cashew ■) In all cases, coating was performed by spraying, and the coating film was heated for drying and curing by controlling the temperature of the mold. Next, polyurethane was injected and laminated onto the resulting coating film. The resulting leather-like multilayer structure was taken out from the inner surface of the mold and evaluated for texture, gloss, and touch.

The results are shown in Table 1. Example 4 The results shown in Table 1 were obtained using a two-component urethane lacquer containing leather powder made of the following formulation, and otherwise in the same manner as in Example 2.

Main agent: NY-Volidur (Mikuni Paint ■) Hardening agent 2NY-Volidur (Hard) (Mikuni Paint ■) Thinner: Made by ξ Kuni Paint ■ The results shown in Table 1 were obtained.

Comparative Example 3 A two-component urethane lacquer containing no leather powder was used instead of the two-component urethane lacquer containing leather powder in Example 4, and the other conditions were the same as in Example 4. We obtained the results shown below.

(Left below) Comparative Example 1 Instead of the leather powder-containing urethane paint of Example 1, Stron Ace YE70 (Cashew ■) was used as a normal urethane paint.
Co., Ltd.) was used to obtain a coating film according to the formulation of ordinary urethane paint shown in Table 1. The results are shown in Table 1.

Comparative Example 2 A non-porous mold was used in place of the porous mold used in Example 3, and the rest was the same as in Example 3. [Effects of the Invention] According to the present invention, A leather-like multilayered structure having a surface appearance, a touch feeling, etc., and having a good texture and a high-class feel can be efficiently manufactured by integral molding.

Essay/diagram

[Brief explanation of drawings]

FIGS. 1(a) to 1(d) are cross-sectional explanatory views showing an example of the outline of the present invention. Code explanation Porous mold Leather powder-containing paint composite or resin leather-like multilayer structure

Claims (1)

[Claims] 1. Paint containing 5 to 50% by weight of leather powder with a particle size of 100 μm or less is applied to the inner surface of a porous mold, dried and solidified to form a coating film, and a synthetic resin is injected and laminated onto the coating film. A method for manufacturing a leather-like multilayer structure, characterized by: