Xonotlite fibrous mineral material and its manufacture

Abstract

Abstract PURPOSE: To obtain the titled material having ≥50μm crystal length, ≤5μm crystal diameter and superior heat and alkali resistances by adding an alkali metal hydroxide to a substance contg. calcium silicate hydrate to cause hydrothermal reaction. CONSTITUTION: A 0.05W1 N aqueous soln. of an alkali metal hydroxide such as NaOH is added to a substance contg. calcium silicate hydrate having a CaO/SiO 2 molar ratio of 0.8W1.0 by ≥ about 5, especially ≥ 10pts.wt./pt.wt. of the substance to cause hydrothermal reaction in an autoclave at 150W400, especially about 240°C under satd. steam pressure. After the reaction the resulting fibrous xonotlite crystals are taken out of the autoclave as an aqueous slurry and separated by filtration or other method. The dried product of the crystals is a white powdered or flaky fibrous mineral material having 0.1W0.2 bulk specific gravity and high water permeability. The crystals are long in fiber size and has superior heat and alkali resistances. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Hiroshi Okazaki
• 👤 Yukihisa Shimizu
• 👤 Masanobu Takarazaki

Bibliographic Details