JPH0649328A - Amino resin molding material - Google Patents

Abstract

PURPOSE:To improve the external properties including gloss and surface smoothness of moldings by compounding an amino resin molding material with a given amount of pulp which has average fiber length and average diameter each controlled in a specific range. CONSTITUTION:An amino resin such as urea resin or melamine resin is mixed with preferably 20-40wt.% pulp with an average fiber length of 20-60mum and an average diameter of 5-20mum. Then, necessary additives such as curing agent (e.g. phthalic anhydride), mold release agent (e.g. wax), filler (e.g. glass fiber) and colorant are added thereto to prepare an amino resin molding material. Use of this material permits production of appliances and utensils which are excellent in appearance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amino resin molding material for producing wiring products, electric appliances, kitchen appliances, household products, miscellaneous goods, etc., particularly molded products with good appearance represented by high gloss and surface smoothness. It is a thing.

[0002]

2. Description of the Related Art Conventionally, molded products made of urea resin and melamine resin are useful because they are hard and have high stain resistance, but recent trends strongly demand good appearance such as high gloss and surface smoothness. Came to be. Although the amount of resin has been increased to cope with this problem, there has been a problem that the strength of the molded product is reduced.

[0003]

As described in the prior art, the amino resin molding material has a problem that the strength is lowered when pursuing good appearance. The present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide an amino resin molding material capable of obtaining a molded product having high strength and good appearance.

[0004]

The present invention has an average fiber length of 2
Since the amino resin molding material is characterized by containing pulp having a particle size of 0 to 60 microns and an average particle size of 5 to 20 microns, the above object can be achieved. The present invention will be described in detail below.

As the amino resin used in the present invention, all amino resins such as urea resin, melamine resin and guanamine resin can be used. The amino resin is a so-called wet type in which it is mixed, kneaded, dried and pulverized with pulp in a liquid resin state. It is preferable to use the above condition. The amino resin also includes a modified amino resin such as epoxy modified or phenol modified.
The pulp needs to have an average fiber length of 20 to 60 microns. That is, if it is less than 20 microns, the strength is lowered, and if it exceeds 60 microns, the appearance is deteriorated. Furthermore, it is necessary that the average particle size is 5 to 20 microns. That is, if it is less than 5, the strength is lowered, and if it exceeds 20 microns, the appearance is lowered. The amount of pulp is preferably 20 to 40% by weight (hereinafter simply referred to as "%") of the total amount. That is, if it is less than 20%, the strength decreases, and 4
This is because if it exceeds 0%, the appearance tends to deteriorate. Phthalic anhydride or the like is used as a curing agent, and resin 100
It is preferable to add 0.01 to 3 parts by weight to parts by weight (hereinafter simply referred to as “parts”). As the release agent, fatty acid, fatty acid metal salt, wax or the like is used, and it is 0.0 to 100 parts of the resin.
It is preferable to add 5 to 5 parts. As the filler and the reinforcing agent, pulp, wood powder, glass fiber, calcium carbonate, talc and the like are used. Further, a colorant is added if necessary.
Thus, the above-mentioned materials are blended, mixed, kneaded, dried if necessary, pulverized, and further granulated if necessary to obtain an amino resin molding material. The molding material is molded by compression molding, transfer molding, injection molding or the like.

The present invention will be described below based on examples.

[0007]

Example 1 1.6 mol of formaldehyde was added to 1 mol of melamine, and 140 parts of a liquid melamine resin having a resin amount of 50% obtained by reacting at 85 ° C. for 1 hour with PH9 was added to an average fiber length of 20 to 40 μm. After adding, mixing, kneading, and drying 30 parts of pulp having an average particle size of 5 to 10 microns, 0.3 parts of phthalic acid and 1 part of stearic acid are added, and then pulverized and dispersed by a jet mill to obtain a melamine resin molding material. Obtained. Next, using a transfer molding machine, the molding material was subjected to a mold temperature of 145 ° C., a molding pressure of 100 Kg / cm ² , and a curing time of 3
Heat-press molding was carried out for a minute to obtain a molded product.

[0008]

Example 2 A molded product was obtained in the same manner as in Example 1 except that pulp having an average fiber length of 40 to 60 microns and an average particle size of 10 to 20 microns was used and was pulverized and dispersed by Turbo RS.

[0009]

COMPARATIVE EXAMPLE A molded product was obtained by the same procedure as in Example 1 except that pulp having an average fiber length of 100 to 200 μm and an average particle size of 40 to 60 μm was crushed and dispersed by a ball mill.

The performances of the molded articles of Examples 1 and 2 and Comparative Example are shown in Table 1.

[0011]

[Table 1]

[0012]

The present invention is constructed as described above.
It was confirmed that the amino resin molding material having the structure described in the claims has a good appearance and is excellent in the present invention.

Claims (2)

[Claims] 1. An amino resin molding material containing pulp having an average fiber length of 20 to 60 microns and an average particle size of 5 to 20 microns. 2. The amino resin molding material according to claim 1, wherein the amount of pulp is 20 to 40% by weight of the total amount.