JPH0233744B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention uses abrasive powder from particle boards that are scheduled for disposal, resulting in a low expansion rate and less distortion during or after molding. The present invention also provides a blank reinforced resin molded product with excellent abrasion characteristics and bending strength characteristics.

(Prior art) Conventional methods for reinforcing resin molded products include mixing inorganic materials such as glass fibers and lock fibers, but it is possible to bring a more natural feel to resin molded products at a lower cost. In recent years, wood powder or similar cellulose substances have been mixed into materials such as polyvinyl chloride, polyethylene, and acrylonitrile-butadiene-styrene (hereinafter abbreviated as ABS) for the purpose of keeping molding costs low. It is something that

(Problem to be Solved by the Invention) Mixing the required amount of wood powder into such a molding resin increases the strength of the resin molded product, especially the bending strength, approximately twice that of a resin molded product without the mixture, and , which significantly lowers the strain rate during resin molding and after molding, and has particularly improved wear resistance, and is meaningful in providing ideal and inexpensive reinforced resin molded products. Despite the excellent properties of the molded product, the inherent properties of the wood flour material contained in the resin significantly reduce the molding properties of the resin, resulting in relatively high molding costs.

In other words, when wood powder is mixed in, the mixed wood powder itself extremely inhibits the fluidity of the molded resin material, and also significantly increases the frictional resistance against the inner wall surface of the molding machine cylinder or the sliding surface of the screw. This requires a particularly low formability per unit time.

This also causes particular wear and tear on the inside of the molding machine, reducing the service life of the molding machine, as well as creating unnecessarily high internal pressure on the die or mold surface, causing breakage and wear of the die or damage and wear of the inside of the mold. At the same time, this caused surface roughness of the molded product itself.

In addition, in the conventional case, mixed wood powder generates a large amount of wood acid, especially acetic acid, etc. during hot molding, and this wood acid significantly reduces the usage frequency of the molding machine cylinder, screw, die, mold, etc., and also causes damage to the surface of the molded product. This caused skin irritation.

In addition, in the conventional method, a large amount of steam is induced by the mixed wood powder, etc., which adheres to the mold surface, causing problems of surface roughness of the molded product and deterioration of the strength of the molded product.

In addition, in addition to such inconveniences in molded products, the wood powder is colored by the unique pigment of the wood powder mixed into the molded product, making it difficult to provide white or colorful resin molded products. It is.

(Means for Solving the Problems) This invention was devised especially in view of the inconveniences in the conventional precedent, and the present invention is designed to reduce the moisture content from 1 to 5% and the particle size to a finer range than 120 mesh. The present invention provides a reinforced resin molded product in which the abrasive powder of a particle board is decolorized with an aqueous solution such as hydrogen peroxide and 3 to 50% by weight is contained in a thermoplastic resin material.

(Example) Hereinafter, a typical example of the reinforced resin molded product according to the present invention will be described. The abrasive powder generated when polishing the surface of a particle board is made into powder particles finer than 120 mesh. Hydrogen oxide water, sodium chlorite water and alkaline type admixtures,
In particular, it is decolored with a mixture of OH-based neutralizers, which destroys the coloring structure of chromophores or auxochromes in the wood components when bleaching the powder, and is unique to abrasive powders. The pigment is removed to obtain a white-like mixed aggregate, and the wood acid contained in the wood powder is neutralized, eliminating the possibility of wood acid gas being generated from the mixed aggregate during subsequent resin molding. .

In addition, since the cell nuclei of the wood in the abrasive powder are destroyed in such bleaching treatment, the thermoplastic resin that serves as the coloring material and crosslinking material during coloring penetrates deep into the cells of the wood, and
This guarantees effective dehydration and creation of extremely dry conditions during the subsequent drying process.

The bleached abrasive powder has a moisture content of 1 to 5.
After drying to about %, vinyl chloride resin,
This resin is molded by mixing it in a thermoplastic resin such as ABS resin or polystyrene resin in a range of 3 to 50%.

Incidentally, it was naturally planned to appropriately color the abrasive powder once it had been bleached, and as a coloring material in molded products, it was possible to provide molded products with the desired color tone. .

In addition, for molding of lightweight materials or molded products that require particular thickness, the thermoplastic resin material may contain azodicarbonamide, azobisformamide, azobisisobutyronitrile, barium azobisformate, N,N′ dinitroso, N, It is planned to mix in a suitable foaming agent such as N' dimethyl terephthalamide in accordance with the desired foaming mode.

In addition, the types of bleaching agents and blending methods mentioned above are not limited to those exemplified, but include sodium peroxide, sodium perborate, potassium permanganate, white powder, advanced white powder, sodium hypochlorite, The use of other comparable bleaches, such as sodium chlorite, is contemplated.

To use such particle board abrasive powder, particle boards that are pressure-formed using a hot press are usually subjected to single-sided or double-sided polishing, and the amount of abrasive powder generated is extremely large. This method takes into consideration the fact that there were many difficulties in the treatment of molded products, and it has made it possible to reduce the cost of molded products.

In addition, the mixed aggregate mentioned above has been subjected to a series of pretreatment processes such as neutralization of abrasive powder and drying to reduce its moisture content to about 1 to 5%. The use of mixed aggregate reduces the generation of water vapor during molding as much as possible, prevents the molded surface from becoming rough, and also prevents the inclusion of various air bubbles.

(Effects of the Invention) The reinforced resin molded product according to the present invention has the above-mentioned characteristic structure, making it possible to provide molded products with various characteristics using the same molding method as in ordinary resin molding. It has a particularly low coefficient of thermal expansion, and also has high dimensional stability with little distortion due to changes in volume and composition due to moisture absorption and water release of wood powder particles used as aggregate during and after molding. This makes it possible to provide molded products with high quality.

In addition, the bending strength as a mechanical property is strong, the hardness is also sufficiently restored, and the surface abrasion characteristics are significantly improved.

Furthermore, the inclusion of wood-based materials makes it possible to process them using ordinary woodworking machines and tools, and also makes it possible to perfect the surface treatment with lacquer, paint, etc., and at the same time, the wood-based mixture allows for the unique color tones of wood. In addition to guaranteeing the feel of the molded product, it is possible to easily provide a molded product having any color tone from a white background. In particular, as a woodworking material, the entire cut surface exhibits wood-like characteristics, and unlike conventional wood-like materials made by spraying, molding, or pasting with decorative sheets, there is no hint that it is a synthetic resin material. It was effective.

In addition, this invention can achieve the above-mentioned effects by using the abrasive powder of particle board, which is normally discarded, and also enables effective use of resources. This could help with recycling, which has become an issue in recent years.

Claims (1)

[Claims] 1 Particle board abrasive powder with a water content of 1 to 5% and a particle size smaller than 120 mesh has been decolorized with an aqueous solution such as hydrogen peroxide, and 3 to 50% by weight is a thermoplastic resin material. A reinforced resin molded product characterized by containing.