JP2632099B2 - Paper and paper products containing rice husk as a material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to paper and paper products containing rice husk as a raw material, and more particularly to paper and paper products made by mixing crushed rice hulls for the purpose of saving and improving pulp.

[0002]

2. Description of the Related Art Conventional paper and paper products are obtained by chopping wood to form wood chips, for example, by digesting it with sulfate to produce wood pulp, or by disintegrating recovered paper as it is,
The waste paper pulp is processed by an alkali method, and it is cut, crushed, fibrillated and dispersed in water by a beater (refining machine) or a refiner (refiner), and then collected and filtered by a paper machine and dried. In this case, a paperboard having a desired thickness is produced by laminating a plurality of sheets in a thin leaf shape or laminating a plurality of sheets in an undried state. In the case of Japanese paper, bast is digested with sulfate to produce bast pulp, which is made by hand pulverizer or paper machine.

[0003] In recent years, turbidity of wood used as a raw material for pulp has caused humus to flow out and roughen the mountain surface, causing serious environmental destruction such as flooding. Therefore, waste paper and corrugated cardboard are collected, and paper is made directly from the treated waste paper pulp or mixed with wood pulp to save wood resources. Compared to the total amount of wood used, it is very small.

Further, since the surface of the conventional cardboard base paper is relatively slippery, there is a problem in that when the cardboard boxes manufactured therefrom are piled up, the upper box collapses due to vibrations or lateral shakes. It is desired to provide non-slip in some way during the manufacturing process.

[0005] In addition, rice husks are discharged in large quantities as industrial waste during threshing, and the amount is as much as one million tons per year in Japan, and its effective utilization is awaited. There is a growing possibility of being used by being mixed into synthetic rubber and cement.

[0006]

SUMMARY OF THE INVENTION In view of the above situation, the present invention seeks to solve the problem in order to save pulp, and thus to save wood resources, and to improve quality.
In particular, it is an object of the present invention to provide paper and paper products containing rice hulls as raw materials by mixing crushed rice hulls with pulp and imparting properties such as anti-slip properties of cardboard base paper to the pulp.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an inner surface comprising rice hulls composed of a screw and an outer cylinder.
Or in the space where the outer surface is spiral and the cross-sectional area gradually decreases
Feeding, under pressure of 1 to 100 t per square cm, 1
After breaking and consolidating at 50-600 ° C,
The crushed rice hulls crushed to a predetermined particle size by a crusher or a crusher and other pulp were allowed to coexist, and paper and paper products containing rice husks produced as a raw material by a conventional papermaking method were constituted. In addition, as a known papermaking method, there are a wet method and a dry method, wherein the wet method is a cutting step of cutting, crushing, fibrillating and dispersing in pulp, and a papermaking step of filtering and collecting and drying. The dry method is a method in which pulp fibers are produced mechanically, aerodynamically or electrostatically by dispersion, sedimentation, suction or adhesion. The former is a method for producing ordinary paper, and the latter is a method for producing nonwoven fabric, flocking, or the like. The following three methods are possible depending on the time when the crushed rice hulls are mixed into the pulp or the intermediate during the processing.

[0008] That is, the crushed rice hulls are mixed with other pulp raw materials and cooked, and the pulp thus obtained is subjected to a preparation step and a papermaking step to form a thin sheet of paper or to be laminated to a desired thickness. The paperboard is made. This includes
This includes cooking only crushed rice husks and mixing the collected paper with the defibrated paper to produce pulp.

[0009] In addition, crushed rice hulls and pulp are mixed, and the resulting mixture is subjected to a preparation process and a papermaking process to produce thin-leaf paper or laminated paper to produce a paperboard having a desired thickness.

[0010] Then, the pulp is subjected to a preparation process and then to an intermediate being processed in a papermaking process, the crushed rice hulls are uniformly adhered and mixed, and a thin leaf-shaped paper or a laminate thereof is laminated to produce a paperboard having a desired thickness. It is.

At this time, it is preferable that the amount of the crushed rice hulls mixed into the pulp is 5 to 50% by weight of the pulp. The amount is appropriately set according to the paper quality and purpose.

[0012]

The paper and paper products containing the rice hulls of the present invention having the above-mentioned contents as raw materials can save pulp by mixing the crushed rice hulls with the pulp. Then, if the rice hull pulp obtained by digestion or digestion with the pulp raw material and the waste paper pulp are mixed, paper and paper products can be obtained from the composite pulp increased in the rice husk by a known papermaking method as it is. In addition, if pulp is mixed with crushed rice hulls and manufactured by a known papermaking method, crushed rice hulls are carried between the fibers of the pulp and fill the gaps, and the density is high and the bending strength is strongly modified. Paper and paper products are obtained. Similarly, the pulp is subjected to the preparation process through the papermaking process to uniformly adhere and mix the crushed rice hulls with the intermediate being processed in the papermaking process, thereby embedding the crushed rice hulls in the surface layer as it is and imparting a non-slip effect to the surface. Paper and paper products are obtained.

Here, the crushed rice hulls used in the present invention are:
150-60 under pressure of 1-100t per square cm
After breaking and consolidating at a temperature of 0 ° C., a known crusher or
Is the so-called compressed and crushed rice hulls that have been pulverized by a pulverizer, with a strong cell structure broken, lignin reduced by half compared to normal rice hulls, and a relatively increased cellulose component rate. Therefore, it is possible to disintegrate by cooking or other known pulp manufacturing methods. In addition, since the crushed rice hulls or rice hull pulp essentially contains natural cellulose as a main component, hydrogen bonds are generated between the natural cellulose fibers that make up ordinary pulp, and the fibers are entangled with each other and strongly bonded to each other. You do it.

[0014]

The crushed rice hulls used in the present invention are not simply those obtained by crushing rice hulls with an ordinary crusher. In normal grinding,
Needle crystals of rice hulls remain and the cell structure is stronger than pulp, and it is mechanically crushed by a grinder, or heated and pressurized in a short time, explosion treatment by sudden decompression, etc.
Alternatively, there is a problem in disintegrating the fibers by a digestion treatment with a sulfate salt or the like chemically. Therefore, the crushed rice hulls used in the present invention are:
Japanese Patent Publication No. 57-31943 invented by the present applicant (see the seed coat, stem,
Method for producing powder of branches and leaves) and JP-B-62-61342
This is pulverized to 10 to 400 mesh by the method and apparatus already disclosed in Japanese Patent Application Publication (compression / crushing apparatus).

That is, the crushed rice hulls obtained by compression and crushing are fed into a space in which the inner or outer surface formed by a screw and an outer cylinder has a spiral shape and the cross-sectional area is gradually reduced. 150-600 ° C under pressure of 1-100t
After being crushed and consolidated in the hot state, it is crushed or powdered by a known crusher or crusher. Table 1 below shows a composition comparison table between the crushed rice hulls thus obtained and ordinary rice husks.

[0016]

[Table 1]

Next, the present invention will be described in further detail with reference to the embodiments shown in the accompanying drawings. FIGS. 1 and 2 illustrate a method of producing pulp by digesting pulp raw material by an alkali method using a normal sulfate as an example, and then producing paper and paper products.

That is, first, wood chips such as softwood and hardwood are shredded to produce wood chips, which are digested with alkali. Alkali is lost in this cooking operation, which is supplemented with sodium sulfate. The supplementation of this lost alkali with sodium sulfate is based on the following principle: sodium sulphate generates sodium sulphide when ignited together with carbon (in the case of pulp, organic matter present in the cooking effluent).
For example, Na ₂ SO ₄ + 4C = Na ₂ S + 4CO, and sodium sulfide generates alkali when dissolved in water. Na ₂ S + H ₂ O = NaOH + NaSH That is, when the waste liquor is concentrated, and the required amount of sodium sulfate is added during incineration and melting, sodium sulfide is formed. The melt thus obtained contains Na ₂ CO ₃ as the main component (65 to 70%), and then contains a large amount of Na ₂ S (about 20%). This is dissolved in water, lime is added, and causticization is performed. It is used for cooking liquor preparation. Then, after performing the digestion treatment, unnecessary components are removed, and bleaching treatment is appropriately performed to produce pulp.

Further, the recovered paper is defibrated as it is or treated by an alkali method to produce pulp. Further, as for Japanese paper, bast is collected from raw materials such as Mitsumata and Kozo, and similarly treated by an alkali (lime, caustic soda, sodium carbonate, etc.) method to produce pulp.

The pulp thus obtained undergoes a preparation process and a papermaking process to produce paper and paper products. In this preparation process, cut with a beater or refiner,
After performing a beating process of crushing and fibrillating, the resultant is dispersed in water to produce pulp water having a predetermined concentration, for example, 1% or less. In the papermaking process, the pulp water is collected by filtration through a net to form a thin leaf, which is then dried. This paper making process is automatically performed by a fourdrinier paper machine,
A roll of base paper is obtained.

Therefore, in this series of papermaking methods, preferred examples of the timing of mixing the crushed rice hulls are shown in FIGS. The mixing time A is mixed as a raw material with other wood chips or bast, etc., and digested as described above.
It produces composite pulp. In this case, the crushed rice hulls are a basic structural material of paper and paper products. At the mixing time B, the wood pulp, the bast pulp or the waste paper pulp and the crushed rice hulls are mixed, beaten with a refiner, and dispersed in water. In this case, the crushed rice hulls do not become a basic structural material of paper and paper products, but are filled and carried between natural cellulose fibers as structural materials, resulting in paper and paper products having high density and bending strength. At the mixing time C, the paper is collected by filtration in the papermaking process, uniformly sprayed or sprayed on the surface of a thin leaf-like intermediate material containing sufficient moisture, and then compressed with a dandy roll. In this case, it becomes a paper and paper product in which the crushed rice hulls are buried in the surface layer, and the crushed rice hulls have their own characteristics, and exhibit the anti-slip and matting effects of the paper and paper products.

The mixing ratio of the crushed rice hulls is appropriately set in the range of 5 to 50% by weight with respect to the pulp according to the quality of the paper and the paper product and the purpose of use. For example, Japanese paper used for shoji paper is preferably about 5% by weight, and wallpaper and the like can be mixed up to about 50% by weight. It is preferable that 5 to 10% by weight of ground rice hulls be mixed into the base paper for the cardboard liner 1 as shown in FIG. 3, and 30 to 50% by weight be mixed into the base 2 base paper.

Although the embodiment described above is a wet method, the mixing times A and B are common even in the dry method, and the mixing time C is after the fibers are sucked or adhered, and the fibers are sprayed or sprayed on the surface. is there. The wet method has been mainstream since ancient times, but there are many problems in terms of pollution, so the dry method will become increasingly important in the future. Since the crushed rice hulls can be finely pulverized to a maximum of about 400 mesh, they have excellent applicability even in a dry method.

[0024]

According to the paper and paper product containing the rice hulls of the present invention as a raw material as described above, the rice husks are
The inner or outer surface composed of is spiral and has a gradually increasing cross-sectional area
Feed into the shrinking gap, 1 to 10 per square cm
Under a pressure of 0 t and hot at 150 to 600 ° C,
After sintering , crushed rice hulls and other pulp crushed to a predetermined particle size by a known crusher or crusher are made to coexist, and it is made by a papermaking method as usual, so the overall paper quality is significantly reduced It is possible to reduce the amount of pulp used without causing the pulp to be used effectively, thereby enabling effective utilization of forest resources and improving the quality of paper and paper products.

Also, after mixing crushed rice hulls with the pulp raw material to produce a composite pulp by digestion or the like, the pulp is made by a known papermaking method, or pulp is mixed with crushed rice husks by a known papermaking method. Then, since the pulp is firmly supported by hydrogen bonds between natural cellulose fibers, the density of paper and paper products and the bending strength or shear strength can be improved. Similarly, by uniformly adhering and mixing the crushed rice hulls with the intermediate being processed in the papermaking process through the preparation process through the preparation process, the crushed rice hulls are buried in the surface layer as it is to impart a non-slip action In particular, when a cardboard base paper is used, when a large number of cardboard boxes manufactured therefrom are stacked, even if vibrations or lateral vibrations occur, the contact surfaces of the cardboard boxes are less likely to slip and collapse.

[Brief description of the drawings]

FIG. 1 is a simplified block diagram showing a process for manufacturing paper and paper products from raw wood.

FIG. 2 is a block diagram showing the process of manufacturing paper and paper products from pulp in some detail.

FIG. 3 is a cross-sectional view of a cardboard.

[Explanation of symbols]

 1 liner 2 center

Claims (5)

(57) [Claims] 1. A rice husk composed of a screw and an outer cylinder
Inside the gap where the surface or outer surface is spiral and the cross-sectional area gradually decreases
Under pressure of 1 to 100 t per square cm,
After breaking and consolidating at 150-600 ° C,
Paper and paper products containing rice hulls as a raw material, characterized by being produced by a conventional papermaking method in which a crushed rice hull crushed to a predetermined particle size by a known crusher or crusher and other pulp coexist. . 2. A pressurized, the <br/> chaff pulverized product was pulverized to a predetermined particle size under heating and cooking mixed with other pulp material,
Paper and paper containing rice hulls as a raw material according to claim 1, wherein thin paper or a paperboard having a desired thickness is produced by laminating thin paper through a preparation process and a papermaking process using the pulp obtained thereby. Product. 3. A pressurization, the <br/> chaff pulverized pulp ground to a predetermined particle size under heat mixing step adjustment formed therewith,
2. A paper and paper product comprising the rice hulls as a raw material according to claim 1, wherein the paper is made into a sheet of paper having a desired thickness by laminating thin paper or laminating it through a paper making process. 4. The pulp is subjected to a preparation process and then to an intermediate being processed in a papermaking process, wherein the crushed rice hulls obtained by pulverizing to a predetermined particle size under pressure and heat are uniformly adhered and mixed to form a thin leaf. A paper or paper product comprising the rice husk as a raw material, wherein the paper or the paperboard is laminated to form a paperboard having a desired thickness. 5. The method according to claim 5, wherein the crushed rice hulls are mixed with pulp in an amount of from 5 to 5.
Paper and paper products containing the rice hulls according to claim 1, 2 or 3 or 4 mixed as 50% by weight.