JPS6213312B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement in a fireproof coating material that is pressure-fed through a hose and sprayed from the tip of a nozzle. Traditionally, this type of fireproof covering material has been made of rock wool, cement,
By mixing 5 to 30% by weight of asbestos into a fire-resistant admixture, the bending and tensile strength of the fire-resistant coating is improved and cracking does not occur during drying. However, asbestos is regulated by the Ordinance on Prevention of Hazards from Specified Chemical Substances, and it is a limited resource and dependent on imports, making it difficult to obtain and increasing prices, so there is a demand for alternatives to asbestos. . Therefore, the present invention was developed as a result of research to reduce the amount of asbestos mixed in, and as a result of research to reduce the amount of asbestos mixed in.
By not incorporating ~30% by weight of asbestos or reducing the amount, and newly incorporating glass fiber,
This has led to the completion of a fire-resistant coating material that has excellent strength properties and does not cause cracks. That is, the present invention mixes 0-20% by weight of asbestos and 0.1-5% by weight of glass fiber into 25-50% by weight of rock wool, 25-40% by weight of cement, and 20-50% by weight of a fire-resistant admixture. The object of the present invention is to provide a fireproof coating material that has improved bending strength and tensile strength and does not cause cracking. The glass fibers are chopped strands of alkali-resistant glass fibers with a bundle of 50 to several 100 fibers and a length of 3 to 50 fibers.
Use mm. Explaining the mixing ratio of glass fiber and asbestos, if large amounts of both are mixed, cracks in the fireproof coating material will be less likely to occur, but if more than 5% by weight of glass fiber is mixed, glass fiber is not as pliable as asbestos. When a pump is used to forcefully feed water through a hose, the pressure increases, requiring a larger pump.Furthermore, glass fibers have poor water absorption, so the glass fibers and water separate when sprayed from the hose nozzle. , the fireproof coating material is likely to fall off, and the inclusion of a large amount of glass fiber also increases costs. Although asbestos does not need to be mixed in at all, it is preferable to add a small amount to compensate for the poor water absorption of glass fibers because of its good water retention properties. In addition, water retention can be increased by adding 0.1 to 1.0% of a thickening agent such as methyl cellulose or polyethylene oxide to compensate for the poor water absorption of glass fibers, so that asbestos can be reduced to a small amount. Chrysotile or amosite asbestos is used as the asbestos, and lightweight aggregates such as silica and alumina are used as the fire-resistant admixture. Example Asbestos and glass fiber were mixed into rock wool, cement, and a fire-resistant admixture at the composition ratios shown in Table 1 (Samples 1 to 4), and water was added to this kneaded mixture to form a paste.
This was sprayed onto the wall from the tip of a hose nozzle to form a fireproof coating. This fireproof coating material was aged for 28 days and its bending strength and tensile strength were measured, and the results are shown in Table 1. For comparison, a conventional fireproof covering material (sample 5) without glass fibers was sprayed in the same manner, and its strength was measured. The bending strength test was conducted using JIS A1106, and the tensile strength test was conducted using a Michalies type universal testing machine.

[Table] If the bending strength and tensile strength of the fireproof sheathing material are large, cracking of the fireproof sheathing material will be less likely to occur.From Table 1, books containing alkali-resistant glass fibers with reduced or no asbestos are mixed. It can be seen that the fireproof coating of the invention has greater bending strength and tensile strength than conventional fireproof coatings that do not contain glass fibers, and does not cause cracking. Further, the fireproof coating material sprayed in the above example was left for three months (summer season), but no cracking phenomenon occurred in the fireproof coating material of the present invention. In the present invention, the fireproof coating material sprayed as described above does not have any cracks.
In addition, by incorporating glass fibers, it is possible to provide an excellent fireproof coating material without problems that would interfere with the pressure-feeding condition within the hose or the spraying process.

Claims (1)

[Claims] 1. Rock wool 25-50% by weight, cement 25-40% by weight,
Fireproof admixture 20-50% by weight, asbestos 0-20% by weight,
Alkali-resistant glass fiber chopped strands
A fireproof coating material in which a composition containing 0.1 to 5% by weight and 0.1 to 1.0% by weight of a thickener is pumped through a hose and sprayed from the tip of a nozzle.