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High ratio of length to diameter of needle like wollastonite powder to its non-toxic, tasteless, non radioactive, etc. gradually replaced the harmful to human health of asbestos, becoming the new raw material of environmental protection building materials in the new century. After special processing technology can still keep its unique acicular structure, so add the impact resistance of wollastonite acicular powder of calcium silicate board, fire board materials, flexural strength, wear strength are greatly improved. In the field of building materials, acicular wollastonite powder will be more widely used!