JPS6321122A - Manufacture of low expansion ratio rigid vinyl chloride resin extruded molding - Google Patents

Abstract

PURPOSE:To bring out trachea-like pores on the surface of a product by a method wherein a low expansion ratio rigid vinyl chloride resin extruded molding is molded and, after that, the skin formed on the surface of the extruded item is scraped off. CONSTITUTION:Together with stabilizer, lubricant, reinforcement and the like, 20-40 parts of woodmeal having the size of 20 mesh and 0.5-4 parts of expanding agent are added to 100 parts of vinyl chloride resin so as to be mixed with one another with a mixer. The resultant mixture is cooled down and charged in an extruder in order to be extruded in a low expansion ratio rigid vinyl chloride resin extruded molding. Next, the skin formed on the surface of the extruded molding is scraped off with a steel wire brush in order to obtain a product. The specific gravity of the obtained product is 0.5-1.0, which is near to the specific gravity of ligneous material. Because continuous trachea-like pores are brought out of the surface of the obtained product, its surface is similar to the surface of ligneous material. When adhesive and coating are applied onto the surface, a part of them penetrate in the pores so as to develop wedge effect, resulting in strengthening their anchoring forces to the surface.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for producing a low-foaming hard vinyl chloride resin extrusion molded product mainly used as an interior material for buildings. This method is characterized by mixing an agent and removing the skin layer formed on the surface of the molded product to expose small conduit-like pores on the surface of the product.

(Prior art) Rigid vinyl chloride resin extrusion molded products are hard and have excellent weather resistance, so they have long been widely used as building materials in place of metal components such as gutters and water pipes. Furthermore, there is an increasing demand for using it as a building material in place of wooden members such as boards and columns. In this case, wood powder is mixed into the material resin, and by doing this, the extruded molded product can be cut with a saw or nailed, but its specific gravity is much higher than that of wood. A skin layer is formed on the surface, which not only has a hard surface and does not have a woody feel, but also has a low affinity with vinyl acetate resin adhesives and paints that are commonly used on wooden parts. Its uses were limited because it was difficult to paint or paint.

(Means for Solving the Problems) The present invention eliminates the drawbacks of the conventional hard vinyl chloride resin extrusion molded products described above.

In addition to wood flour, a resin material mixed with an appropriate amount of a foaming agent is used to mold a low-foaming hard vinyl chloride resin extrusion molded product, and the skin layer formed on the surface is removed and the surface of the molded product is It reveals a small conduit-like pore.

In other words, the present invention is characterized by low foaming of the molded product and by eliminating the skin layer formed on the surface of the molded product.Since the molded product is foamed, its specific gravity is reduced accordingly, making it more woody. Moreover, since the skin layer formed on the surface is thin, it can be easily removed by brushing or the like.

Low-foaming hard vinyl chloride resin extrusion molded products are originally closed-celled, but since wood flour is mixed into this molded product, the cells and wood flour are connected and the molded product appears to be open-celled. Becomes a body.

Therefore, the surface of the molded product from which the skin layer has been removed reveals small (conduit-like) pores in which air bubbles are connected, making it look and feel similar to wood. Furthermore, when paint or adhesive is applied to this material, a portion of it penetrates deeply into the small holes, making the bond with the molded product extremely strong.

(Example) 20 meshes of wood powder 30 parts to 100 parts of hard vinyl chloride resin
1 part of a blowing agent (azodicarboxylic acid amide), and 5 parts of stabilizers, lubricants, reinforcing agents, etc. were added and mixed in a mixer, followed by heating the mixture according to a conventional method, and after cooling it, it was put into an extrusion molding machine. A low-foaming rigid vinyl chloride resin extrusion molded product having a desired shape was molded, and then the skin layer formed on the surface of the molded product was removed using a wire brush using a steel wire layer to obtain a product.

This product has a specific gravity of 0.5 to 1.0, which is similar to wood, and its surface has conduit-like pores with continuous air bubbles.
It resembles a woody surface. Furthermore, when adhesive and paint were applied to the surface of the product, a portion of the adhesive and paint penetrated into the small pores, creating a wedge effect and strengthening the adhesion to the surface.

Claims (1)

[Claims] 100 parts of vinyl chloride resin, 20 to 40 parts of wood flour, 05 to 4 parts of a blowing agent, a stabilizer, a reinforcing agent, etc. are added and kneaded, followed by extrusion molding of a low-foaming hard vinyl chloride resin according to a conventional method. 1. A method for producing a low-foaming rigid vinyl chloride resin extrusion molded product, which comprises molding the product and then removing a skin layer formed on the surface of the molded product.