JPS6110406A - Manufacture of fiber reinforced cement molded shape - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a fiber-reinforced cement molded body used, for example, as a building material.

(Prior Art) Conventionally, a fiber-reinforced cement molded article is produced by mixing short fibers into unhardened cement, and dispersing the mixed short fibers into the unhardened cement by stirring the unhardened cement. It is manufactured by subsequently curing the uncured cement.

(Problems to be Solved by the Invention) In the conventional method for producing the fiber-reinforced cement molded article, even if a deflocculation agent such as polyethylene oxide is used as disclosed in JP-A No. 53-80423,
As shown in Figure 1, before the short fibers a are mixed into the unhardened cement (b), they become entangled in the direction of the unhardened cement (b) at the interface of the unhardened cement (b), forming clumps, and are uniformly distributed in the unhardened cement (b). This has the disadvantage that the mechanical strength of the obtained fiber-reinforced cement molded product varies.

(Means for Solving the Problems) An object of the present invention is to provide a method for producing a fiber-reinforced cement molded body in which short fibers are uniformly dispersed in cement and have excellent mechanical strength. In a method for producing a fiber-reinforced cement molded body, which comprises dispersing short fibers in unhardened cement and then hardening the unhardened cement,
The short fibers are oriented in a certain direction and loosely bound with a binder and mixed into the core unhardened cement, and the unhardened short fibers are loosened by stirring the mixed short fibers and the unhardened cement. As the cement, which is characterized by being dispersed in unhardened cement, any cement such as Portland cement, alumina cement, blast furnace cement, silica cement, fly ash cement, and shetset cement can be used.

In addition, short fibers to be dispersed in cement include inorganic fibers such as carbon fibers, glass fibers, and ceramic fibers, aromatic polyamides, and aromatic 71? IJ etheramide, aromatic polysulfide amide, aromatic polysulfonamide,
Organic fibers such as aromatic polyketone agglomerate and aromatic polyamine amide, gold M fibers such as steel fibers, etc. are used, and are blended in a proportion of about 0.5 to 10% by volume to the cement.

Such short fibers generally have a denier of 1 to 50 and a fiber length of 5 to 3.
Use 0m long ones and loosely bind several hundred to several thousand of them with a binder.

As the binder, a curable resin such as an epoxy type or a phenol type, an inorganic type such as colloidal silica, a composite type thereof, or the like is appropriately used depending on the properties of the short fibers to be bound.

one! The degree of bundling of short fibers with a heavy binderffl
, depending on the short fibers to be bound and the type of binder, the short fibers that are bound? When mixed into unhardened cement and stirred with an onim mixer, it binds into a seed layer that is easily untied.

In this case, the volume ratio of short fibers and binder is 5=5 to 9:
Generally, it is about 1.

(Example) An example of the method for manufacturing a fiber-reinforced cement molded article of the present invention will be described below with reference to the accompanying drawings.

As shown in the first figure, carbon fiber short fibers 1 are oriented in one direction, loosely bound with an epoxy resin binder 2, and thrown into uncured cement 3 made of Portland cement. At this time, the short fibers 1 are oriented in a certain direction and remain loosely bound by the binder 2, so that no lumps are formed at the interface of the uncured cement 3 due to the entanglement of the short fibers 1.

Next, stirring of the unhardened cement 3 using an onim mixer (not shown) is started. At this time, as shown in ttI3, the short fibers 1 are gradually unbound by the binder 2, but are dispersed deep into the uncured cement 3 while maintaining their orientation in a certain direction.

When the unhardened cement 3 is continuously stirred, the short fibers 1 are almost completely untied and dispersed extremely uniformly in the unhardened cement 3 without intertwining with each other to form a lump, as shown in FIG. The uncured cement 3 in which the short fibers 1 are dispersed is cured to obtain a fiber-reinforced cement molded body.

(Effects of the Invention) As described above, according to the method for producing a fiber-reinforced cement molded body of the present invention, short fibers are oriented in a certain direction and loosely bound with a binder and mixed into unhardened cement,
By stirring the short fibers mixed in the unhardened cement, the short fibers are dispersed in the unhardened cement while loosening their bonds, so that the short fibers can be dispersed very easily and uniformly in the unhardened cement. This has the effect of producing a fiber-reinforced cement molded product with excellent mechanical strength.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing the state when short fibers are introduced into uncured cement in the conventional manufacturing method of fiber-reinforced cement molded bodies, and Figs. 2 to 4 show the fiber-reinforced cement molding of the present invention. FIG. 3 is a cross-sectional view showing the state of dispersion of short fibers in uncured cement in the method for manufacturing the body. ■...Short fiber 2...Binder 3...
uncured cement

Claims (1)

[Claims] In a method for producing a fiber-reinforced cement molded body, which comprises dispersing short fibers in unhardened cement and then hardening the unhardened cement, the short fibers are oriented in a certain direction and loosely bound with a binder. Fiber-reinforced cement molding characterized in that the short fibers are mixed into the unhardened cement and the short fibers are dispersed in the unhardened cement while untying the short fibers by stirring the unhardened cement. How the body is manufactured.