JPH0450422B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a skin body having a porous surface layer, and more particularly to a method for manufacturing a skin body having a porous surface layer having a suede-like surface condition. Examples of products using such molded skin products include:
Examples include automobile interior parts such as crash pads, door trims, console boxes, and glove box slids. (Prior Art) Synthetic resin skins that have been conventionally used for automobile interior parts such as those mentioned above generally play a decorative role in the interior of the automobile, and their main purpose is to improve comfort when coming into contact with passengers. Therefore, having appropriate strength against friction and impact was an essential quality requirement. However, today's skin has diversified user preferences, and when used in products that come into direct contact with the user's body, it goes without saying that it satisfies the mechanical properties mentioned above, but also It has become necessary to pay attention to the texture of the skin. However, for example, conventional polyvinyl chloride skins formed by rotational molding, blow molding, vacuum forming, etc. accumulate heat and soften when exposed to high temperatures, resulting in a hot or sticky feeling when they come into contact with the user's skin. In addition, when it is cold, it hardens and cools, giving the user an unpleasant feeling of coldness. Therefore, these epidermal bodies form a synthetic leather-like surface layer through skin-wringing, etc., to provide the above-mentioned heat sensation and
Although attempts were made to reduce the discomfort of the cold sensation, they had the drawback of reflecting direct sunlight, irritating the driver's eyes, and reflecting the windshield on the windshield, obstructing the driver's view. In order to prevent such defects, attempts have been made to flock the surface of the skin body or to bond the cloth itself together, but these methods are extremely expensive and difficult to mold, so today, Generally speaking, it is hardly used. (Problems to be Solved by the Present Invention) The present invention addresses the above-mentioned drawbacks and aims to economically produce a skin body having a porous network ventilation layer on the surface of a non-foamed layer serving as a strength layer. The aim is to improve this by (Means for Solving the Problems) That is, the present invention is characterized by charging a polyvinyl chloride plastisol or powder material mixed with a foaming agent into a mold, and then molding the material into the mold. After forming a foam layer on the surface by foam molding, a polyvinyl chloride plastisol or powder material is then put into the mold, and the temperature of the mold is raised to form a non-foam layer on the surface of the foam layer. A foam layer is formed and adhered to the surface, and a skin body consisting of a foam layer and a non-foam layer with a skin layer on the side in contact with the mold surface is removed from the mold by lowering the mold temperature, and then this skin body is removed from the mold by lowering the mold temperature. The skin layer of the foamed layer is dissolved by leaving it in a solvent vapor and exposing it to the solvent vapor to form a skin having a porous surface. The specific details will be further explained below with reference to the accompanying drawings. 1 to 3 are cross-sectional views showing one example of manufacturing a skin body in the method of the present invention at each step, in which a skin mold 1 is a slush mold, and a mold 3 having an opening 2. is installed on a mold support member 4, and iron jackets 5 are placed on the outside of the mold 3 at intervals of 5 to 15 mm. The space 6 formed by the mold 3 and the jacket 5 forms a space into which heat medium oil such as heavy allylbenzene oil flows, thereby heating and cooling the mold 3. This heating oil has a rating of 210 to 270 in heating systems.
℃, and a cooling system of 20 to 50℃, the heating system is used for heating, and the cooling system is used for cooling, which flows into the space 6 between the jacket 5 and the mold 3 to cool the mold 3.
The temperature is being adjusted. Of course, the temperature adjustment of the mold is not limited to the above-mentioned heating medium oil, and other methods such as high-frequency induction heating, spraying combustion heat of propane gas, kerosene, etc. may also be adopted, and when cooling, water may be used. It may also be applied by spraying. Furthermore, the mold 3 used in the method of the present invention has a thickness of 2.5 mm.
In addition to the ~5.0 mm nickel electroforming mold, copper electroforming molds, aluminum precision casting molds, and thermal spraying molds can also be used. Next, to describe the manufacturing process of the epidermis, first,
The mold 3 is filled with a skin material 7 made of vinyl chloride plastisol mixed with a foaming agent or a vinyl chloride powder material. Specifically, the skin material is made of vinyl chloride resin and plasticizer. , plastisol consisting of stabilizers, lubricants, foaming agents, etc., and powder compounds with a particle size of 50 to 250μ made by kneading, absorbing, and adsorbing plasticizers, stabilizers, lubricants, foaming agents, etc. to vinyl chloride resin with porous particle shape,
Alternatively, it is a powder compound made by kneading plasticizers, stabilizers, lubricants, foaming agents, etc. with vinyl chloride resin, gelling it, cooling it, and turning it into powder by a pulverization method, etc.
The foaming agent mentioned above is ADCA (Azodicar
bonamide), DPT (Di−
nitrosopentamethyleneteramine), urea compounds, etc., and the amount added is 1 to 10 parts by weight per 100 parts by weight of plastisol or powder compound.
parts by weight, preferably 5 to 15 parts by weight. At this time, the mold 3 is heated or preheated to a predetermined temperature, but specifically, heat medium oil of a high-temperature heating system is flowed into the space between the mold 3 and the jacket 5, and the mold 3 is inserted. The temperature is raised to such a temperature that the skin material partially melts and adheres to the mold surface. That is, the temperature is adjusted to a temperature at which the skin material begins to gel, for example, a powder material starts to gel and the surface of the powder becomes sticky, usually 80°C to 100°C. After filling the mold with the skin material 7 and heating it for about 25 to 35 seconds, the skin material 7 adhering to the mold is discharged.
At this time, a polyvinyl chloride foam layer 8 is formed on the surface of the mold. Next, the mold 3 is immediately filled with polyvinyl chloride plastisol or powder material, and approximately
After 25-35 seconds, drain the excess material and tighten the mold 3 to approx.
The temperature is raised to 170° C. to 180° C. and heated for about 50 to 90 seconds to form a skin body 11 in which the foamed layer 8 with a thickness of about 1 mm and the non-foamed layer 9 with a thickness of about 0.5 mm are integrally melted.
Thereafter, the mold 3 is cooled to approximately 50 to 70° C., and the skin body 11 is removed from the mold by inputting. The skin 11 thus obtained has a foamed layer 8 and a non-foamed layer 9 as shown in FIG. 4, and an extremely thin skin layer 10 is formed on the surface of the foamed layer 8. Such skin body 11 is then treated with a solvent such as trifluorotrifluoroethane, methylene chloride, butyl chloride, ethylidene chloride, ethylene dichloride, acetylene dichloride, ethylene trichloride, benzene monobromide, benzene monochloride, benzene dioxide, dioxane. It is steam treated by exposing it to the steam of a low boiling point solvent such as for 60 to 180 seconds. Of course, these solvents are not limited to one type, and a mixed solvent can also be used. The skin layer 10 on the surface of the non-foamed layer 9 of the skin body 11 thus obtained is dissolved as shown in FIG. 5 to form a skin body having a porous surface layer 12 with air permeability only on the surface portion. do. In addition, in the method of the present invention, an extremely thin skin layer 10 is formed on the surface of the foam layer 8 of the skin body 11 consisting of the foam layer 8 and the non-foam layer 9. The surface of the mold has good thermal conductivity, and the heat generated during the foaming reaction is released from the mold, so it is inevitable that the foaming reaction will be limited. Even if the skin layer 10 is dissolved, it will take a very long time and the surface of the non-foamed layer 9 may also be dissolved. Therefore, in order to perform surface treatment in a short time, it is preferable to use a skin body in which an extremely thin skin layer 10 is formed on the surface of the foam layer as described above, and a slush molding method is one means for molding such a skin body. This can be said to be the most preferable method. At the same time, the above-mentioned slush molding method is preferable from the viewpoint of economically and efficiently molding the two layers of the foamed layer 8 and the non-foamed layer 9 serving as the reinforcing layer. However, in the method of the present invention, 2
It goes without saying that rotational molding is also possible as a means of forming the skin body consisting of layers. More specific examples will be shown below. (Example) Table 1 shows the formulation of the polyvinyl chloride plastisol that forms the foamed layer, and Table 2 shows the formulation of the polyvinyl chloride plastisol that forms the non-foamed layer.

【table】

[Table] First, a slush molding mold preheated to 90℃ is filled with the foaming plastisol shown in Table 1 above, and after being left for 30 seconds, this plastisol is discharged to form a foam with a wall thickness of approximately 0.5 mm. A gelled layer was formed on the inner surface of the mold. Then, immediately fill it with non-foaming plastisol shown in Table 2, and after 30 seconds, discharge the plastisol.
After raising the mold to 180℃, heat it for 60 seconds,
Both layers were completely melted and integrated. Thereafter, the mold was cooled to about 60° C. and the skin was removed from the mold. The skin has a foamed layer of about 1mm and a non-foamed layer of 0.5mm.
mm thick, and a skin layer was observed on the surface of the foam layer. The epidermis was then dried by exposing it to trichloromonofluoroethane vapor for 90 seconds. The surface of the foam layer of the skin body was dissolved and only the surface portion had air permeability. (Effects of the Invention) As described above, the method of the present invention has two layers, a foamed layer and a non-foamed layer, and a skin layer on the surface of the foamed layer. By leaving the skin in a solvent vapor, By dissolving the skin layer on the surface of the foam layer and creating a skin with a porous network surface that is breathable, it prevents the user from experiencing contact discomfort such as hot or cold sensations. At the same time,
By creating a suede-like surface condition, it is possible to give a soft touch and warmth, making it possible to significantly improve the conventional skin finish.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are explanatory diagrams showing the manufacturing process of a skin body having a foamed layer with a skin layer and a non-foamed layer in the method of the present invention, and Figure 4 is an illustration of the manufacturing process of a skin body used in the method of the present invention. 5 is a cross-sectional view of a skin body having a porous surface layer obtained by the method of the present invention. 7...Skin material, 8...Foamed layer, 9...Non-foamed layer, 1
0...skin layer, 11...epidermal body.

Claims (1)

[Claims] 1. A polyvinyl chloride plastisol or powder material mixed with a foaming agent is put into a mold, and the material is foam-molded on the surface of the mold to adhere a foam layer to the surface. PVC plastisol or powder material is put into the mold, the temperature of the mold is raised to form a non-foamed layer on the surface of the foamed layer, and a skin is formed on the side in contact with the mold surface. After molding a skin body consisting of a foamed layer and a non-foamed layer, the mold temperature is lowered and the mold is removed, and then this skin body is left in a solvent vapor, and the foamed layer is removed by exposing the skin body to the solvent vapor. 1. A method for producing a skin body having a porous surface, the method comprising dissolving a skin layer of the layers to form a skin body having a porous surface.