JPH10279699A - Molding and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molding which fully utilizes the unnecessary part of plants of the family Gramineae and contains no thermosetting resin as a binder by molding a mixture containing a product of grinding of the straws of plants of the family Gramineae as the principal material and a binder being a water- based adhesive based on a styrene/acrylic copolymer. SOLUTION: A principal material being a product of a grinding of the straws of plants of the family Gramineae, desirably a residue from the straws of sugar canes after a sugar extraction step is impregnated with 50-100 pts.wt. (in terms of the adhesive), based on 100 pts.wt. product of grinding, water-based adhesive based on a resin component being a styrene/acrylic copolymer to prepare an impregnated molding material. This material is molded at ordinary temperature under elevated pressure or molded under applied heat and pressure to obtain a molding. This molding can be used as a substitute for an existing woody board. As compared with the case in which a thermosetting resin is used, the use of the water-based adhesive can make it possible to facilitate the step of drying the molding material, to eliminate the necessity for a step of pressing under high-temperature and high-pressure conditions and to obtain a molding containing no residual solvent, etc., harmful to the human body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded product using a crushed or broken product of a plant of the grass family (corn, sugar cane, rice, etc.) and a method for producing the same.

[0002]

2. Description of the Related Art Conventional wood-based boards and the like are manufactured by molding a wood-based chip or fiber into a flat plate using a thermosetting resin as a binder. The main raw material of the wood-based material used as a raw material is natural wood resources, and in recent years, its depletion has become a problem worldwide, and the depletion of wood resources has an adverse effect on the global environment. Thermosetting resin, which is one of the raw materials, is used to bond wood-based materials to each other to impart strength as a molded body. Requires a high pressure press. For this reason, there is a danger of fire, burns, dust explosion, and the like, and labor is required to maintain a safe working environment. In addition, since the manufacturing process becomes longer, the manufacturing cost tends to increase. Further, it is said that even in the completed molded body, since a solvent such as formalin remains, there is an adverse effect on the human body.

[0003]

While the depletion of wood resources is at stake, the same cellulose resources are produced in large quantities in grasses every year, and unnecessary portions of stems and the like are discarded in large quantities. ing. For example, after extracting a sucrose-containing liquid from sugarcane, the stem is broken and crushed in the extraction process, except that only a small part is used as fuel or feed, etc. Has been disposed of. In particular, since the stems of sugarcane after extraction contain a large amount of water, even at the present stage, even disposal treatment is a problem.

[0004] Therefore, an object of the present invention is to provide a molded article which effectively utilizes an unnecessary portion such as a stem of a grass plant and does not use a thermosetting resin as a binder, and a method for producing the same.

[0005]

As a means for solving the above-mentioned conventional problems, the present inventor has created the following invention. That is, the invention according to claim 1 is a molded article formed by using a crushed material of a stem of a grass plant as a main raw material and a water-based adhesive mainly containing a styrene acrylic copolymer as a resin component as a binder. is there. ADVANTAGE OF THE INVENTION According to this invention, a molded object can be easily manufactured using another lignocellulose resource as a raw material, without using a wood resource.

According to a second aspect of the present invention, there is provided the molded article according to the first aspect, wherein the gramineous plant is sugarcane. According to the present invention, sugarcane is used as a lignocellulose resource other than wood resources.

According to a third aspect of the present invention, in the molded article according to the first aspect, the grass plant is sugarcane;
The crushed stalk is a molded product characterized by remaining sugarcane stalk remaining after the sucrose extraction step. ADVANTAGE OF THE INVENTION According to this invention, the stem crushed material of the sugarcane after extraction of the sucrose solution which is discarded in large quantities is effectively used.

According to a fourth aspect of the present invention, a crushed product obtained by crushing the stem of a grass plant is impregnated with an aqueous adhesive mainly containing a styrene acrylic copolymer as a resin component. A method for producing a molded article, comprising preparing a molding material and molding the impregnated molding material by pressing.
According to this method, a water-resistant molded body can be easily produced from a gramineous plant that is a lignocellulose resource other than a wood resource.

According to a fifth aspect of the present invention, there is provided the method for producing a molded article according to the fourth aspect, wherein the gramineous plant is sugarcane, and the crushed material is a sugarcane stalk having undergone a sucrose extraction step. A method for producing a molded article, characterized by being a residual material. According to this method, the remaining material can be effectively used.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The molding material in the molded article of the present invention is a stem of a grass plant. Examples of the gramineous plant include rice, corn, and sugarcane, and are preferably sugarcane. The skin portion of the sugarcane stalk is rigid, the crushed material is convenient as a molding material for a highly rigid molded body, and the central core of the stalk is advantageous in that the degree of freedom and accuracy of the molding shape is high. is there.

The form of the crushed stem is not particularly limited as long as a molded body can be formed. As the crushed material of the stalk of sugarcane, for example, the crushed material of the epidermis of the stalk is relatively rigid, having a length of 10 mm to 50 m.
m in the form of flakes.
A fibrous body having a length of about 5 mm and a length of about 10 mm, and a fluffy granular body or powdery body. Preferred as a crushed product is a residue of sugarcane that has been subjected to a sucrose solution extraction step. This is because, in this residual material, the stalk is already crushed in the sucrose solution extraction step. In the sucrose solution extraction step, usually, the cut sugarcane is transported and pulverized while being held down by a roller having a tooth-shaped convex, and a solution containing sucrose is extracted.

[0012] The crushed material of the epidermis and the core of the sugarcane are:
They may be used together, or each of them may be selected and used. The molding process is easier for the crushed skin portion, and the molding accuracy is better for the crushed core portion. Further, the crushed skin portion is suitable for a material of a panel material for a building, and the crushed core portion is suitable for a material of a molded body having a three-dimensional three-dimensional shape.

The water-based adhesive used in the present invention is a water-soluble adhesive mainly containing a styrene acrylic copolymer as a resin component. In the present invention, by using the water-based adhesive, the drying step of the molding material and the like are simplified as compared with the case where a thermosetting resin is used as in the related art. Also, a high-temperature and high-pressure pressing step is not required. Further, no organic solvent harmful to the human body remains in the molded body. As such an aqueous adhesive, a styrene acrylic copolymer is used as a main resin component, an evaporation residue is 40%, and a clay (cp / 30 ° C.) is 35%.
ISONO- which exhibits anionic chargeability at 0 and pH 8.7
Agent A can be mentioned.

[0014] The amount of the water-based adhesive used for the crushed material of the stem of a grass plant is added according to the water content of the crushed material. Preferably, the adhesive 5 is used for 100 parts by weight of the crushed material.
0 to 100 parts by weight.

Various known methods can be used to impregnate the crushed material with the water-based adhesive. However, a mixture of the crushed material and the water-based adhesive is kneaded under a condition where the crushed material is pressurized. Is preferable because the water-based adhesive can be effectively and uniformly impregnated into the crushed material. The impregnated molding materials include:
In addition to the crushed material and the water-based adhesive, other additives such as a coloring agent such as a pigment, a decorative additive such as a ceramic chip, and various additives which are usually added to a wooden board can be included.

The impregnated molding material obtained by impregnating the crushed material with an aqueous adhesive is then molded in a pressing step,
The molded body has a predetermined shape. The water content of the impregnated molding material is 30
If it is less than 10% by weight, molding is possible only at normal temperature and under pressure. Heat-press molding is also possible.

In molding by press working, it is preferable to use a sugar cane skin as a main body in order to obtain a plate-like body, and to form a plate-like body having a curved surface which is not flat, in order to obtain a plate-like body. Is preferably used as a main component. Further, according to this molded article, since the thermoplastic resin is used as a binder component, the molded article can be once molded into a flat body, then heated again to melt the thermoplastic resin, and then molded again into another shape. For the formation of such an intermediate-like plate-like body, it is preferable to mainly use the central part of the sugarcane.

Since the obtained molded article is molded in a state where the crushed material is impregnated with the water-based adhesive, it has good water resistance and good shape retention. . By laminating the obtained molded bodies and bonding them with a water-based adhesive, a laminated body can also be formed.

According to the molded article and the method for producing the molded article, it is possible to provide a molded article that replaces the current wood-based board without consuming wood resources because the gramineous plant is used as a molding material. In particular, as a molding material,
When the residual material (Bagaso) after the extraction of the sugarcane sucrose solution is used, it is possible to eliminate the disposal of the bagasse and to easily produce a useful board. In addition, since the water-based adhesive is used as the binder, the molded body can be made into a moldable state again by heating the molded body again, and can be reused.

[0020]

According to the first to third aspects of the present invention, it is possible to provide a molded article that can be reused by using lignocellulose resources other than wood resources. Claims 4 and 5
According to the invention, a molded article that can be easily reused can be provided using lignocellulose resources other than wood resources.

[0021]

【Example】

(Example 1) In this example, a flat plate was manufactured by using a skin material among crushed residual materials after extraction of a sucrose solution from a cane stalk.

After the bagasse that has been subjected to the sucrose solution extraction process from sugarcane is sufficiently washed with water, dehydration and sorting of the crushed material derived from the epidermis portion and the crushed material derived from the core portion are simultaneously performed using a three-dimensional vibrating sieve. Was. The obtained crushed material derived from the epidermis is
It was an amorphous flake of 10 to 50 mm.

To 100 parts by weight of the crushed material, 70 parts by weight of an ISONO-A material (manufactured by Isano Co., Ltd.) are added as a water-based adhesive. The mixture was put into a kneading tank provided with two rotating blades and mixed well to obtain an impregnated molding material in which the aqueous adhesive was uniformly impregnated in the crushed material.

After the impregnated molding material was weighed and filled into a molding die, it was hot-pressed with upper and lower heaters heated to 150 ° C. to 160 ° C. for 5 to 10 minutes under a pressure of 10 kg / cm ² . The obtained molded body was 250 mm × 25
It was 0 mm x 4 mm. Further, when water was flowed on the surface of the molded body, the surface repelled the water and was kept in a water droplet state.

(Example 2) In this example, a molded body was manufactured in the same manner as in Example 1 except that the core material of bagasse was used as a molding material. The obtained molded body was 250 mm × 2
It was 50 mm x 4 mm. Similarly, when water was flowed on the surface of the molded body, the water was kept in a water droplet state on the surface.

(Embodiment 3) This embodiment is an example in which the flat plate obtained in Embodiment 2 is heated to give another shape. After the flat molded product obtained in Example 2 was placed on a mold for door trim of an automobile, the flat molded product was held in a constant temperature bath at 160 ° C. for 30 minutes, and then was subjected to electrothermal spraying to soften the flat molded product. After being made into a shape-processable state, it was pressed to obtain a trim base material. The softened plate-like molded body had a good mold-following property, and was accurately molded into a trim shape.

(Embodiment 4) This embodiment is an example in which the flat molded bodies obtained in Embodiment 1 are laminated to form a laminate. The molded product obtained in Example 1 (size 250 mm × 250 mm ×
4 mm) are sprayed and applied to one of the surfaces facing each other when these molded products are laminated, and then the molded products are superposed on each other by spraying.
Hot pressed at 00 ° C. for 2-3 minutes. As a result, the three molded bodies were adhered to each other by the ISONO-A material, and one laminated body that was firmly integrated could be obtained.

Claims (5)

[Claims] 1. A molded product obtained by using a crushed material of a stalk of a gramineous plant as a main raw material and an aqueous adhesive mainly composed of a styrene acrylic copolymer as a resin component as a binder. 2. The molded article according to claim 1, wherein said grass plant is sugarcane. 3. The molded product according to claim 1, wherein the grass plant is sugarcane, and the crushed stem is a residue of the sugarcane stem that has been subjected to the sucrose extraction step. Molding. 4. An impregnated molding material is prepared by impregnating a crushed material obtained by crushing the stem of a grass plant with a water-based adhesive mainly composed of a styrene acrylic copolymer as a resin component. A method for producing a molded article, comprising molding an impregnated molding material by pressing. 5. The method according to claim 4, wherein the gramineous plant is sugarcane, and the crushed material is a residue of a sugarcane stem that has been subjected to a sucrose extraction step. A method for producing a molded article.