JP2635458B2 - Processing method of reinforcing fiber for inorganic building materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating reinforcing fibers for inorganic building materials, and more particularly to a method for effectively utilizing waste paper pulp.

[0002]

2. Description of the Related Art Conventionally, it has been indispensable to add reinforcing fibers to inorganic products mainly composed of cement or the like in order to impart product strength. In recent years, pulp fibers have been used instead of asbestos fibers as the reinforcing fibers. Widely used. By the way, the use of pulp fiber is becoming a cause of mass consumption of wood, and its use is gradually restricted due to the problem of forest protection. Various attempts have been made to effectively use waste paper pulp, which is industrial waste. Of the waste paper used as a pulp fiber recycling resource,
Since the waste paper of milk carton paper is formed from very high quality pulp, its effective utilization is desired.

[0003]

Problems of the prior art By the way, the above-mentioned milk carton paper is usually coated on the front and back surfaces with wax, so that the fiber hardly disintegrates due to the wax. If it remains as a lump, it remains in the cement matrix as it is and causes a reduction in product strength. Even though it is a pulp of high quality, there is a drawback that it cannot be effectively used as a reinforcing fiber of a cement product.

[0004]

DISCLOSURE OF THE INVENTION In view of the above problems, the present invention is directed to treating inorganic building material reinforcing fibers such that the entire amount thereof can be used as pulp fibers as reinforcing fibers even in the waste paper of milk carton paper. It is intended to provide a method.

[0005]

In other words, the method for treating reinforcing fibers for inorganic building materials according to the present invention is to beat the waste paper of milk carton paper to a freeness of 600 to 750 ml and to remove the beaten waste paper.
The treatment is carried out with a solution of PH 9 to 14 heated to 110 ° C. or higher, followed by dehydration.

[0006]

The milk carton paper used in the present invention is a paper formed of 100% green pulp and used as a packaging container for milk products such as milk. The milk carton paper is subjected to a wax treatment on the front and back surfaces for the purpose of waterproofing, and the wax content impairs the strength of the cement product as described above. Therefore, in the present invention, the milk carton paper is beaten to a freeness of 600 to 750 ml by a beater, and the beaten fibers are treated with alkali to remove the wax content.

The reason why the milk carton paper is beaten in the above is to facilitate the removal of the wax content by defibrating into a fibrous form, and its freeness value is set to 600 to 75.
The reason why the volume is set to 0 ml is that if the volume is lower than 600 ml, the fiber length tends to decrease, and if the volume is higher than 750 ml, undissociated lumps remain. When this beating pulp is treated with a solution of PH 9 to 14 heated to 110 ° C. or higher, the wax dissolved by heat is saponified with an alkali and eluted into the solution. Therefore, almost no wax remains in the waste paper pulp after this treatment, and no harm is caused even if the whole amount is used as pulp fiber.

[0008]

Next, an embodiment of the present invention will be described. The milk carton paper is beaten to a freeness value of 720 ml with a beater, and after visually confirming that there is no undisintegrated fiber, water is added to the beaten fiber so as to have a solid concentration of 4%, and then the dispersion is subjected to hydroxylation. The pH was adjusted to 11 by adding calcium, and a hot alkali treatment was performed in an autoclave at 110 ° C. for 8 hours. Thereafter, dewatering was performed to obtain waste paper pulp having a water content of 10%. Using this treated pulp as a reinforcing fiber, add 8% by weight of the treated pulp to a mixture of 40% by weight of cement, 42% by weight of fly ash, and 10% by weight of pearlite, and after uniform mixing, add water 5 mm in width, 45 cm in width and length. Form a 90cm long plate,
Cured and cured by autoclave.

As a comparative example, a test plate was formed in the same manner as in the above-mentioned Example except that a waste paper pulp of a milk carton paper simply beaten to a freeness of 820 ml was used without performing a hot alkali treatment. When the bending strength was measured for the above Examples and Comparative Examples, the results shown in Table 1 were obtained.

[0010]

[Table 1]

As is clear from Table 1, it was found that the material treated according to the present invention had excellent strength despite the fact that the whole amount was waste paper pulp.

[0012]

As described above, the present invention makes it possible to effectively use the waste paper of milk carton paper which could not be added as it is in the past. Can be performed simultaneously and simultaneously during the autoclave curing of the cement product, and thus have various effects such as less waste of energy.

Claims (1)

(57) [Claims] 1. The waste paper of milk carton paper is freeness 6
A process for treating reinforcing fibers for inorganic building materials, which comprises beating to 00 to 750 ml, treating the beaten waste paper with a solution of PH 9 to 14 heated to 110 ° C. or higher, and then dewatering.