JPH0359802B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention involves mixing relatively fine wood flour with an adjusted pH value into a synthetic resin material such as vinyl chloride resin as a molding aggregate, and press molding, extrusion, injection molding, etc. The purpose is to provide a synthetic product that has the features of wood and resin.

Therefore, one of the anticipated main objectives of the present invention is to improve the molding properties by imparting characteristics to the mixed wood flour aggregate, and to prevent wear and tear of the extrusion or injection cylinder part during molding. The objective is to eliminate inconveniences such as breakage of molded parts and roughness on the surface of the molded product, and to improve the compatibility between the mixed aggregate and resin material, thereby providing a composite product that does not generate cavities on the surrounding surface of the aggregate. It was placed in

Next, one of the other objects anticipated in the present invention is to provide characteristics to the mixed wood flour aggregate so that a relatively large amount of aggregate can be produced easily, that is, even in the forming operation. Also, it is possible to mix in the conforming surface of the molded resin material, and with this, cooling shrinkage distortion is small, and there is no distortion, warping, cracking, etc.
Moreover, the modulus of elasticity is 3 compared to ordinary vinyl chloride molded products.
The aim is to provide a composite product that is twice as strong and has a sufficiently hard surface.

Furthermore, one of the other main objectives of the present invention is to easily mass produce and provide materials that have various characteristics unique to wood by molding them into any shape by pressing, extrusion, injection molding, etc. It was placed in such a way that it could be done.

Another main objective of the present invention is that it has superior abrasion resistance compared to the characteristics of the material to be molded, has no shrinkage due to molding shrinkage, and is more durable than wood in actual use. The aim is to provide a composite product that has the same surface characteristics as the above, i.e., color tone, texture, and can be painted, bonded, laminated, etc.

The method for molding a composite product according to the present invention is intended to achieve the various purposes described above, and includes the following specific examples and other equivalent examples accompanying these examples. Equal measures are planned.

A typical method for molding a composite article for building materials or fittings according to the present invention will now be explained in detail.

First, the materials to be prepared are vinyl chloride,
Thermoplastic resin materials such as ABS resin and polystyrene,
These are mixed aggregate based on wood flour, and calcium carbonate powder hardener, stabilizer, coloring agent, etc. that are added as necessary.

The thermoplastic resin material used was determined and used based on the selection criteria that satisfies the various needs required for molded articles, and is used as a building material,
Vinyl chloride resin is commonly used as a material for fittings and the like because of its molding properties, suitable strength and hardness of molded products.

The aggregate used was then neutralized using the following procedure. That is, crushed chip material,
A cellulosic material such as pulp or rice husk is prepared and pre-processed by drying, especially heat drying, so that the moisture content of the material is within 15%. As the moisture content in the material decreases to less than 15%, the drying process rapidly induces destruction of the constituent fiber structure of the material, causing the crushed chips to become rough bundles or lumps of cellulose. Of course, the composition of the cellulose in pulp material and rice husk is definitely destroyed, and the cellulose is in a disorganized state.

By applying an emulsion-type urea resin adhesive to the material that has dried and whose structure has disintegrated, and leaving it for 20 to 30 minutes,
This urea-based resin adhesive liquid is sufficiently impregnated into the material, and usually has a pH value of about 5.

In addition, ammonia chloride or hydrochloric acid is separately added to this resin adhesive liquid as a hardening agent, and the material
Attempts were made to further adjust the pH value toward neutrality as necessary.

In this way, the material impregnated with the urea-based resin liquid and cured is subjected to heat drying at a temperature of 100 to 150°C and crushing into powder in the next step. The moisture content should be within 3-5%, as close to 0% as possible, and the particle size should be 100-150%.
It is made into a fine powder about the size of a meshi.

During such heat drying and crushing, the material itself
The pH value is within the range of 6 to 7, and it is generally adjusted to be neutral.

The neutralization treatment of the acidic material at such a starting point is
This is largely due to the action of the urea-based resin adhesive that is interposed during the process, and in simple heating and drying treatments of cellulose materials that do not include the addition of urea-based resin adhesives. Compared to the pH5 of the starting material, the final point material, which is made into a dry fine powder,
The PH value is 2 to 3, which means that the PH value tends to be acidic. On the other hand, by interposing a urea-based resin adhesive, the PH5 material is neutralized while gradually releasing the acetic acid contained in the material as wood acid gas as it is heated and dried. The pH of the material is adjusted to within the neutralization range of 6 to 7.

The aggregate thus provided can be heat treated during processing to reduce the water content in the aggregate by up to 13%.
Within, ideally within 3-5%, and even 0% as much as possible
This prevents the generation of water vapor during the subsequent resin molding with aggregate mixed in, and also prevents the dissociation and volatilization of the lactic acid contained in it, eliminating the possibility of acid gas generation, and sufficiently Neutralization treatment is applied,
Its pH value is 6-7.

In addition, the aggregate used is heated and dried in the pulverization process of the aggregate, and before the aggregate is formed.
That is, appropriate drying to the degree of dryness that is separately required for the wood chips or pure wood powder, the form of agglomerates during the shaping process, or the form of shaped granular aggregates. The means were considered.

In the aggregate thus provided, the wood acid contained in the wood powder, especially acetic acid gas, evaporates during impregnation and heat molding with a thermosetting resin material mainly consisting of the above-mentioned urea resin. This effectively reduces the possibility of acid gases being generated from the aggregate used in the subsequent process of mixing the aggregate into the resin material and molding it.

In addition, most of the water contained in the aggregate is evaporated due to the heating and drying process applied during aggregate molding, so there is no generation of water vapor, which is considered to be a problem in resin molding using molded aggregate. , there is no room for foaming, cavities, rough skin, etc. to occur in the molded product. still,
Removal of this water content can also have a significant effect on the volatilization of wood acid contained in wood flour.
The wood acid contained in wood flour usually dissociates and volatilizes only after reacting with H20 groups, so this is effectively suppressed. Therefore, the pH of 6 to 6 due to neutralization and elimination of wood acid produced during the process of heat crushing and curing by impregnation with the thermosetting resin material.
In addition to the adjustment in step 7, the generation of residual wood acid gas from the aggregate was more effectively suppressed.

Effective elimination of wood acid gas in such aggregates,
Prevention of this occurrence has an extremely important meaning in subsequent resin molding. In other words, when wood acid gas is generated during resin molding, the cylinder screws of presses, extruders, and injection machines used for resin molding, or the inner wall surfaces of molds or molds, are oxidized and corroded, reducing their service life. This drastically reduces the frequency and also reduces the molding efficiency, causing the problem of molding defects due to uneven extrusion and injection pressures.

In addition, unlike ordinary pure wood flour, the surface resistance value of the aggregate is extremely reduced due to the hardening resin being impregnated or attached to the aggregate. The extrusion and injection pressure when mixed and molded into the material is almost similar to that of common resins. On the other hand, in the past, the mixing of wood powder caused the wood powder to slide against the inner circumferential surface of cylinders, dies, etc., causing frictional resistance, and when extrusion and injection were performed, cylinders, dies, etc. This causes scratches, abrasion, or damage on the inner circumferential surface of the

Furthermore, the use of such aggregates ensures good compatibility with the mixed resin material, ensuring uniform mixing of the aggregates,
In addition, the voids generated on the peripheral surface of the aggregate in the molded product are eliminated as much as possible, making it possible to provide a molded product with initial quality.

The calcium carbonate powder prepared next is used as needed to prevent molded products from deforming during extrusion processing, etc., and to keep the unit price of molded products low since calcium carbonate itself is particularly cheap. It is something that

In addition to these materials, a separate stabilizer such as lead was prepared in an attempt to prevent deterioration in the molded product and to reduce as much as possible the frictional resistance that occurs during extrusion processing.

Furthermore, when the molded product is to be colored, a corresponding coloring agent is prepared. For example, when the molded product is made white, titanium oxide is mixed in.

The materials described in detail above include those that are provided in the form of pellets by being pre-mixed with a resin material such as vinyl chloride resin, and those that are mixed into powdered resin such as vinyl chloride resin. In some cases, it is supplied as a resin molding machine, and it is selectively supplied and used depending on the type of resin molding machine, etc. used.

Therefore, when making pellets, first mix the above-mentioned aggregates within 50wt% with powdered resin, add calcium carbonate as necessary within 10wt%, and then add The required stabilizers, aggregates and coloring agents are mixed and kneaded and heated to obtain pellets for molding. Using the pellets for molding thus obtained, the desired synthetic product was obtained by the same method as in ordinary resin molding.

Another method that will be planned next is to use a method similar to the method used to create pellets, in which various materials are put into a molding machine to directly obtain a molded product, kneaded, and molded by heating.

In addition, since the above-mentioned aggregates are planned to be mixed, the main molding methods for such resin molded products are generally press molding, extrusion molding, or injection molding, and extrusion foam molding is partially planned. It is what was done.

The amount of aggregate to be mixed is determined according to the resin molding method and the characteristics of the molded product, and is approximately within the range of 20% to 50% by weight.

Furthermore, depending on the resin material used, the amount of aggregate, the molding method, etc., the processing temperature can be set within the range of about 110℃ to 170℃, and the above-mentioned properties can be expected to be achieved specifically. This makes it possible to provide a composite product that combines the advantages of plastics.

In particular, it is now possible to easily mold various molded products that were previously considered almost impossible to mold due to the fact that the wood powder mixed in with the wood powder produces wood acid gas, or that the wood powder has particularly high slip resistance. It could have been done.

In addition, the molded product is compatible with the resin material used due to the characteristics of the mixed aggregate, and resin molded products with good quality characteristics can be provided using normal molding methods and normal molding efficiency. It could have been done.

In addition, due to the characteristics of the aggregate, it does not induce excessive frictional resistance or cylinder pressure in the molding machine itself, and also prevents roughening of the inner peripheral surfaces of the cylinder and die, making it easy to use the equipment used. The depletion rate in the process is particularly low.

As mentioned above, molded products that are resistant to this type of material have excellent water resistance, abrasion resistance, and impact resistance, and have a hard surface. , distortion, warping, cracking, etc. after molding are reliably prevented, and the elastic modulus is also particularly good.

In addition, the thermal deformation rate is low, and at the same time, machinability, paintability,
It has adhesive properties, nailing properties, etc., and is said to have particularly good construction properties.

The wood used can be either softwood or broadleaf, as the cellulose fibers are made into fine short fibers, ie, fine powder, without being crushed.

The method of molding the wood-like synthetic material according to the present invention includes the above-mentioned method, and the actual molded products are used as architectural members, such as door frame materials, window frame materials, surrounding edging materials,
Skirting boards, curtain boxes, edge edges, angles, tesli, flooring materials, wall materials, thresholds, lintels, doorstops, etc., as well as fittings such as shoji frames, doors, sash doors, louvers, etc., for furniture and automobiles. A wide range of applications are planned, including for ships, home appliances, various cabinets, sinks, and more.

Claims (1)

[Scope of Claims] 1. For crushed chips, pulp, rice husks, and other appropriate cellulose-based materials, the water content of the material is 15%.
% or less to induce collapse of the fiber structure, the processed material is impregnated with a urea resin solution, and then the processed material is heated within a temperature range of 100°C to 150°C. The process involves drying, crushing, and molding neutralized fine aggregate with a pH of 6 to 7. This neutral fine aggregate is mixed into vinyl chloride or other thermoplastic resin, and resin molding is performed using an appropriate molding method. A method for forming a wood-like synthetic object, characterized by a process of forming a wood-like composite object. 2. A method for forming a wood-like composite material according to claim 1, characterized in that the particle size of the aggregate is 100 mesh or more and the water content is 5% or less.