JPS5935786B2 - Manufacturing method of "Tsuki" decorative sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a decorative dust board sheet in which a backing base material such as nonwoven fabric, paper, or cloth is adhered to the back side of a single dust board.

Conventionally, probe veneers made from stripped raw wood tend to warp, crack, and crack when their moisture content drops below the fiber saturation point (approximately 30%), making them extremely difficult to handle.

Therefore, when creating a decorative probe board by pasting a dust board veneer to a base material such as plywood or particle board, use The most commonly used method was the so-called wet bonding method, in which the materials were stacked on top of each other and then bonded under heat and pressure.

However, when the base material is flexible and stiff, such as nonwoven fabric, paper, or cloth, it is necessary to use a coating device such as a spretzer when applying adhesive to the top surface, compared to base materials such as plywood. Not only is it difficult to apply adhesive, but the base material itself absorbs water and expands significantly, creating gaps at the joints between the veneer plates and the veneer plates. Due to the difference in expansion and contraction rates with the base material, problems such as the surface of the decorative sheet being wavy and not being finished smoothly have arisen.

Therefore, as a result of research to solve the above problems, it was found that cracks and cracks in wood occur because the water distribution in the wood cells becomes uneven from the moment the water content drops below the fiber saturation point (around 30%). By focusing on the phenomenon that occurs, we uniformize the moisture distribution within the dust veneer by heating the veneer under pressure and forcibly adjusting the moisture content within the range of 10 to 20% in a short period of time. This also causes a setting phenomenon in the material, making it an easy-to-handle veneer with no cracks or cracks even after being left under pressure.The thermoplastic adhesive film can then be used to create flexible materials such as nonwoven fabrics, paper, cloth, and synthetic resin sheets. By heat-pressure bonding with the backing material, we have been able to produce a probe plate decorative sheet that is smooth, flexible, and has good adhesive performance without cracking or curling. Hereinafter, the present invention will be explained in detail with reference to Examples.

The probe plate is a single plate with a thickness of about 0.2 to 1.07 nm.
Its water content is high, exceeding the fiber saturation point.

In this example, the water content is 50 to 55 with an O, 2n zelkova probe.
% was used. Next, pressurize and heat the above single probe plate with a flat press or roll press to reduce its moisture content to 10.
Adjust to a range of ~20%.

Pressurize and heat the wet probe board veneer to reduce the moisture content to 10-20%.
This is done by forcibly adjusting the moisture content of the probe veneer to a range of 10 to 20%, which is close to the equilibrium moisture content of the atmosphere, for a short period of time under pressure. By equalizing moisture distribution and correcting the setting phenomenon in the material, making it look like it has been ironed, it is easy to handle and has no cracks or cracks even if left in the atmosphere after depressurizing. The purpose is to obtain a dry probe veneer. In this example 110℃
Insert a wet probe plate between the hot press heating plates and heat to 0.
Pressed for 15 seconds at a pressure of 5 to 1 kg/Cd, and the moisture content was 1.
A dry dust board veneer containing 0 to 15% was used. Next, a thermoplastic adhesive film is layered on the top surface of the dried dust board veneer, and a flexible base material is further layered on the top surface and bonded by thermocompression.

Thermoplastic adhesive films that can be used in this invention include polyolefin, petitral phenol, putadiene, polyamide, and ionomer resins, and flexible base materials include rayon, acetate, polyester, nylon, acrylic, and cotton. , nonwoven fabrics made of glass fibers, cloth or paper, and various synthetic resin sheets.

In this example, an ionomer adhesive film with a thickness of 30μ, rayon with a thickness of 300μ, and polyester nonwoven fabric are placed on the top surface of the same dry veneer board in this order, and are inserted between hot press plates at 120 to 130℃, and then heated at a pressure of 10kg/Cd. It was heat-pressed for 30 seconds to form a decorative plate sheet. The drying time and temperature of the veneer board are determined by the wood species, initial moisture content, thickness, etc. of the veneer board, and the conditions for bonding the veneer board to the nonwoven fabric are determined by the type of adhesive film used. Therefore, it must be determined through preliminary experiments. Since the dust board decorative sheet of the present invention is manufactured with the above-described configuration, there is no gap between the joints of the square board veneers even on the flexible base material.
Moreover, it has the effect of being able to be manufactured as a smooth probe plate decorative sheet without any waviness on the decorative surface.

Claims (1)

[Claims] 1. Heat the veneer board under pressure using a plane press or roll press to adjust the moisture content to 10-20%, then apply nonwoven fabric, paper, or cloth to the top surface of the veneer board via a thermoplastic adhesive film. ,
■ A method for producing a decorative board sheet, which is characterized by stacking flexible base materials such as synthetic resin sheets and then bonding them under heat.