JPH0543293A - Production of fiber reinforced cement plate - Google Patents

Abstract

PURPOSE:To produce a fiber reinforced cement plate which is enhanced in adhesive properties of both pulp fiber and a cement matrix and excellent in flexural strength in the case of using pulp fiber as reinforcing fiber. CONSTITUTION:In blending a fiber reinforcing cement plate obtained by adding the necessary amount of pulp fiber as reinforcing fiber, the other lightweight aggregate and a filler or the like, cationic paper force increasing material is added to pulp fiber at 1-4 wt.% for the weight of pulp fiber. This mixture is mixed previously and uniformly and thereafter mixed with the other blending material such as cement and silica. A platelike body is formed of the obtained mixture, cured and hardened. The adhesive properties are improved by making the surface of pulp fiber cationic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fiber-reinforced cement board, and more particularly to a method for producing a fiber-reinforced cement board containing asbestos.

[0002]

2. Description of the Related Art Heretofore, a product obtained by molding a plate-like body from a cement mixture and curing and curing the plate-like body has been widely used as a building board material. This kind of inorganic plate material has various advantages such that products of the same quality and the same shape can be easily mass-produced, and since it does not consume any natural resources such as wood at all, it is convenient from the viewpoint of resource protection. By the way, asbestos has been conventionally widely used as a reinforcing fiber for these inorganic plate materials. However, since asbestos causes pollution, it is strongly requested that its use be restricted or totally abolished, and various alternative reinforcing fibers are being sought. Pulp fiber is a promising alternative fiber for asbestos because it is superior to other fibers in terms of chemical resistance and heat resistance.

[0003]

[Problems of the prior art] However, pulp fibers do not have the property of positively capturing powder materials such as cement, unlike asbestos, and the adhesiveness to the cement matrix is poor even after curing as a product and the fiber There was a problem that slip-through occurred and did not contribute to sufficient strength improvement.

[0004]

In view of the above problems, the present invention, when using pulp fibers as reinforcing fibers, improves the adhesion between the pulp fibers and the cement matrix and produces a fiber-reinforced cement board having excellent bending strength. It was made for the purpose of obtaining a method.

[0005]

That is, a method for producing a fiber-reinforced cement board of the present invention is a method for producing a fiber-reinforced cement board by adding necessary amounts of pulp fibers as reinforcing fibers, other lightweight aggregates, fillers and the like. In the formulation, the pulp fiber contains a cationic paper strengthening material in an amount of 1 to 4% by weight based on the weight of the pulp fiber.
It is characterized in that it is added and uniformly mixed in advance, and then other compounding materials such as cement and silica are added and uniformly mixed, and a plate-like body is molded from this mixture and cured.

[0006]

The cement composition used in this invention is
35-45% by weight of cement, 35-45% by weight of silica powder, 1-6% by weight of pulp fiber, 2-5% by weight of lightweight aggregate, and other fillers such as silica sand are used as the remaining weight%. It has the same composition as that of

In the present invention, polyacrylamide resin, prior to mixing the pulp fibers with other materials,
A surface treatment is performed by adding 1 to 4% by weight of a cationic paper-strengthening material such as polyamide / polyamine / epichlorohydrin resin and mixing them uniformly. The pretreatment with the cationic paper-strengthening agent is for improving the surface of the pulp fiber. If it is less than 1% by weight, this improving effect is not obtained, and if it is more than 4% by weight, the improvement is not achieved. It is good, but there is no effect commensurate with the addition, which is uneconomical. Therefore, the above range is preferable, and 2% by weight is preferable in this range.

The surface of pulp fiber is -O,-of cellulose molecules.
Since it has an anionic property due to the OH group, it is considered to have a low powder-capturing power, and the paper-strengthening agent as described above is added to make the surface cationic like asbestos.
The addition of the cationic paper strengthening agent improves the adhesiveness to powder materials such as cement and the effect of preventing wastewater pollution. Therefore, when it is mixed with another cement compounding material, the adhesion between the pulp fiber and the powder material is improved, and the strength is improved.

[0009]

Embodiments of the present invention will be described below. cement
In a cement mixture consisting of 47% by weight, silica powder 48% by weight, and pulp fiber 5% by weight, pulp fiber contains 1% by weight, 2% by weight, 3% by weight and 5% by weight of a cationic polyacrylamide resin with respect to the pulp fiber. The paper-strengthening agent consisting of and the paper-strengthening agent consisting of polyamide / polyamine / epichlorohydrin resin are mixed and then mixed with other cement and silica materials to add water to a thickness of 5 mm. A plate-like body having a length of 45 cm and a length of 90 cm was molded and cured by autoclaving. A bending test was then performed on the obtained plate material, and the results shown in Table 1 were obtained.

[0010]

[Table 1]

[0011]

As described above, according to the present invention, the surface of pulp fiber is treated to be cationic like asbestos fiber, and then mixed with a powder material such as cement, so that the binding property between the fiber and the powder material is improved. Is improved, the adhesion between the matrix and the reinforcing fiber is improved, and the strength can be improved to nearly 20% as compared with the case where no addition is made.

Claims (1)

[Claims] 1. A compound of a fiber reinforced cement board comprising a required amount of pulp fiber as a reinforcing fiber, other lightweight aggregates, a filler, etc., in which a cationic paper-strengthening material is added to the pulp fiber in the weight of the pulp fiber. Fiber reinforced characterized by adding 1 to 4% by weight to the mixture and premixing it homogeneously, and then mixing with other compounding materials such as cement and silica, and molding a plate from the mixture to cure and cure. Cement board manufacturing method.