JPH05139464A - Packing material using rice husks and manufacture of the same - Google Patents

Abstract

PURPOSE:To obtain easily and cheaply a packing material easy to dispose and prominent in various performances by a method wherein an adhesive is attached on surfaces of rice husks so that the rice husks get together by a large amount to form an assembly, and the obtained assembly is molded under pressure, and then hardened to make a packing material. CONSTITUTION:To manufacture a packing material, first an assembly 3 of rice husks 2 is added with a proper amount of adhesive 4 and solvent, so that the adhesive 4 is attached on surfaces of the rice husks 2 uniformly. Then the rice husks 2 are closed inside a prescribed molding container 20, in which pressure is increased high enough to increase concentration, so as to match desired strength and elasticity. In succession, a cube 13 of the rice husks 2 is housed in a drying stove 30 together with the molding container 20 to undergo a hot air drying process for hardening treatment. Thereby combination strength is increased. After that, a rice husks mold is cooled down to an atmospheric temperature, whereby the packing material 1 is made completely. The packing material 1 thus obtained can be disposed without any bad influence on environment. Further, the packing material 1 is prominent in various performances such as strength, shock absorption, sound absorption, ventilation, heat insulation and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packing material using rice husks and a manufacturing method thereof.

[0002]

[Prior Art]

(Background of the Invention) Rice husks are known to have a shell structure rich in elasticity and toughness because they are made of silica or the like with a fibrous solid structure by the natural shaping that covers and protects rice. .. In addition, rice husks have been reduced to soil in agriculture and used in bedding for livestock in the past, and industrially used as an auxiliary material for iron making and also as an abrasive by processing into powder,
Used for plastic fillers. Furthermore, rice husks have been used as cushioning materials in the form of roses in the past years, filled and used in the empty space of luggage (eg, fruits, eggs, potatoes, shrimp crabs, etc.). However, due to the cumbersome handling of unpacking after unpacking, it is gradually shunned and the frequency of use is decreasing. (Prior Art) Conventionally, as a shock absorbing material or void filling material for packaging, natural rice husks described above have been used for a long time, or plastic foams centered on styrofoam, plastic sheet moldings, wood products, paper products. Etc. are known.

[0003]

Among the natural rice husks described in the prior art, convenience is extremely poor,
In the case of chemical packaging materials centering on Styrofoam, waste material processing has become a social problem from the viewpoint of environmental destruction.

As a result of intensive studies to eliminate the above disadvantages, the present invention utilizes the rice husk alone for its lightness, elasticity, toughness, air-holding power, and weatherability stability. The aggregate of is solidified while applying a suitable pressure according to the purpose of use with an adhesive, is rich in elasticity, has many voids and is lightweight and has sound absorbing properties, while maintaining breathability, The inventors have found that it can be an extremely excellent packaging material having heat retention and heat insulation properties, and have completed the present invention based on this finding.

Therefore, an object of the present invention is to provide a packaging material which does not adversely affect the environment even when natural rice husks are joined by an adhesive, molded into an arbitrary three-dimensional shape, and disposed of after use, and a packaging material therefor. It is to provide a manufacturing method. Another object of the present invention is to provide a packaging material excellent in strength and impact relaxation property and a manufacturing method thereof. Another object of the present invention is to provide a packaging material that is excellent in sound absorption due to its large porosity, is light and durable, and a method for manufacturing the same. Yet another object of the present invention is to
An object of the present invention is to provide a packaging material excellent in breathability and heat insulation and a manufacturing method thereof.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a packing material using rice husks, which are formed by press-molding an aggregate of rice husks having an adhesive uniformly adhered to the surface thereof, and then hardening it. And the first step of uniformly adhering the adhesive to the surface of the rice husks, and the second step of adjusting the strength and elasticity of the aggregate of the rice husks to which the adhesive is adhered to increase the density and form the shape. And a third step of curing the shaped product obtained in the second step by hot air drying or the like, and a method for producing a packaging material using rice husks.

[0007]

EXAMPLES Next, the present invention will be described in detail with reference to its preferable examples. Prior to the embodiments, the present invention will be comprehensively described. In the manufacturing process of a packing material using rice husks according to the present invention, first, an appropriate amount of an adhesive (paste type or emulsion type) 4 and a solvent (for example, alcohol; but a solvent) is added to the assembly 3 of the rice husks 2. Is optional)
Add the adhesive (resin) to the surface of the rice husks evenly. Next, the rice husk 12 to which this resin is evenly attached is
It is enclosed in a molding container 20 having a shape to be molded in advance, and the density is increased by appropriately applying pressure so as to match the desired strength and elasticity. Initially, the bulk specific gravity of rice husk is 0.0
It is about 85 to 0.090, but it is preferable to increase the bulk specific gravity to 0.15 to 0.25 by applying a compressive force. Molded product 13 when the bulk specific gravity is 0.15 or less
The compressive strength and tensile strength of P.
This is because if it is 25 or more, the elasticity decreases. After that, the pressure-molded rice husk cube 13 together with the molding container 20 is subjected to hot air drying or the like in a drying furnace 30 and is subjected to a curing treatment to increase the bonding strength. The rice husk molded product that has undergone the molding and curing (molding heating) step is cooled and returned to room temperature to obtain the packaging material 1. As the plastic resin used as the adhesive, polyethylene resin, polypropylene resin,
Acetal resin, acrylic resin, vinyl acetate resin, polyurethane resin, phenol resin, epoxy resin and the like can be used. It is important to attach the resin to the aggregate of rice husks evenly, but the rice husks should be moistened in advance, and an appropriate amount of powdered adhesive (plastic adhesive) should be added and stirred well. Needless to say, this powder may be uniformly attached to the surface of the chaff. Therefore, the adhesive may be any type of paste, water-soluble, emulsion and powder. Further, as a method of curing the pressure-molded and standardized material, there are A. Curing type [chemical reaction (eg, in the case of two-part epoxy resin), drying (eg, in the case of vinyl acetate resin emulsion), heating (eg, in the case of polyethylene resin)], or B.I. Curing method [heating (electric heating, infrared heating, high frequency heating, hot air high pressure steam), ultraviolet irradiation,
Electron beam irradiation, leaving (cooling, moisture absorption, evaporation, air blocking)]
Can be used.

The following is a description of embodiments of the present invention. Example 1: In the first example, a method of joining rice husks was tried using a thermoplastic polyethylene resin as an adhesive. First, 250 g of water is added to 500 g of rice husk to make a material having a water content of 35%, and 100 to 200
250 g of μ polyethylene resin powder was added, and the mixture was stirred using a mixer so that the powder was dispersed and attached to the surface of the moist rice husk. The chaff after stirring was placed in a cylindrical container, and was compacted from above with an air-permeable piston, and the volume after molding was 2.8 liters relative to the original volume of 5.6 liters. Put the rice husks in the compacted cylinder into the drying furnace as it is in the cylinder container, and send the hot air of 130 ° C generated by the electric heat blower to heat the inside of the rice husks sufficiently to remove the moisture impregnated in the rice husks. Hot air was blown until the majority was lost by evaporation. Since the adhesiveness of rice husks is rich in voids, the pressure loss is low, and hot air easily permeates the inside to promote the evaporation of water, and the water is lost in 8 minutes, and the polyethylene powder is pasted. Even if it became a shape, it joined the chaff. When heat was taken out from the mold and left at room temperature of 23 ° C. for heat dissipation, hardness and elasticity were generated, and a chaff molded product that could be used as a packaging material was obtained. Example 2: A method for joining rice husks was tried using a water-soluble emulsion of vinyl acetate as an adhesive. 100 g of a water-soluble emulsion of vinyl acetate containing 200 g of rice husks with a water content of 50% was sufficiently kneaded using a mixer to uniformly adhere the adhesive to the surface of the rice husks. Put the chaff into a cylindrical cylinder made of glass after kneading, and consolidate from the top with a breathable piston to make a lid, with an original volume of 220 cc.
On the other hand, the volume after molding was set to 110 cc. Even in this way, the glass cylinder in which the rice husks were compacted was placed in a hot-air dryer, and after taking 20 minutes after applying a temperature of 110 ° C., most of the water in the emulsion was evaporated, and a part of the rice was chaffed. Once in the shell tissue, the rice husks were molded into the desired shape. When the molded product was taken out of the cylinder and allowed to stand at room temperature, a desired chaff molded product was obtained. Example 3: An attempt was made to join rice husks using a thermosetting solvent-based phenolic resin. First, to 1 kg of rice husks, 500 g of the phenolic resin for adhesion (the weight after drying became 265 g) was added, and the mixture was stirred using a mixer so that the phenolic resin uniformly adheres to the surface of the rice husks. did. After the stirring, the chaff was put into a glass cylindrical container, which was then compacted from above with an air-permeable piston to make the original volume of 5.6 liters and the molded volume of 2.8 liters. When the rice husks in the compressed cylinder were treated with hot air at 220 ° C. in the same manner as in Example 1, the phenolic resin bonded the rice husks in 20 minutes and cured,
A desired hard rice chaff molding was obtained.

[0009]

The present invention is configured as described above, and the present invention has the following effects. The packaging material according to the present invention uses natural rice husks as the main material, and effectively utilizes the unique properties of the rice husks, and therefore is extremely inexpensive and causes environmental damage even when discarded after use. Is less likely to cause the problem. Further, according to the manufacturing method of the present invention, a packaging material having the following characteristics can be obtained. B) The rice husks have excellent strength because they are combined vertically and horizontally and in diagonal positions in a disordered arrangement and bonded. B) It has excellent cushioning properties because it has the elasticity unique to rice husks and is further compressed to further strengthen it. C) It has excellent sound absorbing properties due to its excellent cushioning property and large porosity. D) Light weight and easy handling. E) Since it has a lot of voids, it is excellent in breathability and heat insulation, and the packaged luggage is less affected by the climate. Thus, the obtained packaging material can be used as a wide range of packaging materials for electrical equipment, machinery, food, etc., and can also be used as cushioning materials, soundproofing materials, sound absorbing materials, heat insulating materials, and heat insulating materials as building materials. Is.

[Brief description of drawings]

FIG. 1 is a perspective view of a packaging material using rice husks according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a state in the mixer when the rice husks and the adhesive are put into the mixer and stirred so that the adhesive is uniformly attached to the surface of the rice husks.

FIG. 3 is an enlarged perspective view showing three rice husks to which an adhesive is attached.

FIG. 4 is a schematic cross-sectional view showing a state in which a rice husk having an adhesive on the surface of the rice husk is housed in a container.

FIG. 5 is a schematic cross-sectional view showing a state in which the rice husk aggregate is pressurized from the state of FIG.

FIG. 6 is a schematic cross-sectional view showing a state in which a plurality of pressure-molded chaff aggregates are dried in a drying oven with hot air in a container.

FIG. 7 is a schematic view showing a state in which the rice husk aggregate that has been dried by hot air is cooled and taken out from the container.

FIG. 8 is a schematic diagram of a flow diagram showing a manufacturing method of the present invention.

[Explanation of symbols]

 1 Packing material 2 Rice husk 3 Rice husk aggregate 4 Adhesive

Claims (2)

[Claims] 1. A packing material using rice husks formed by press-molding an aggregate of rice husks having an adhesive uniformly attached to the surface thereof, and then hardening the shaped. 2. A first step of uniformly adhering an adhesive to the surface of rice husks, and a pressure-molding to increase the density while adjusting the strength and elasticity of the aggregate of the rice husks to which the adhesive has adhered to form a fixed shape. And a third step of curing the shaped product obtained in the second step by hot air drying or the like, and a method for producing a packaging material using rice husks. ..