Low-cost lightweight chalk

Abstract

The invention discloses low-cost lightweight chalk. The low-cost lightweight chalk is prepared from the following raw materials in parts by weight: 20-65 parts of modified gypsum powder, 5-12 parts of calcium carbonate, 1-6 parts of plant ash, 2-10 parts of diatomite, 0.2-0.9 part of acid dye, 1.5-2 parts of sweet orange oil and 80-130 parts of water. A preparation method of the modified gypsum powder comprises the following steps: feeding gypsum powder and nanometer titanium dioxide into an autoclave to preserve heat for 40-80 minutes; taking the heat-preserved gypsum powder and nanometer titanium dioxide out, and drying; adding 1,2-bis(triethoxysilyl)ethane and deionized water, and stirring, wherein the stirring speed is 1,200-2800 revolutions per minute and the stirring temperature is 45-65 DEG C; adding sodium glycocholate and an ethanol solution to perform ultrasonic dispersion, wherein the ultrasonic dispersion temperature is 65-75 DEG C, and the ultrasonic dispersion time is 20-40 minutes; filtering, washing, drying and smashing to obtain the modified gypsum powder. The low-cost lightweight chalk has the advantages of less possibility of powder dropping, small specific gravity, convenience in writing, firmness, and durability, is free of organic solvents and has no harm to the environment and human health.

Description

technical field [0001] The invention relates to the technical field of chalk, in particular to a low-cost light chalk. Background technique [0002] Dust-free chalk is an improved product of ordinary chalk. It refers to the elimination of chalk dust pollution in classrooms. It just adds oil or polyalcohol to ordinary chalk as a binder, and then adds fillers with a larger specific gravity, such as clay and marl. Rock, cement, etc., increase the proportion of chalk dust, and writing is laborious. In addition, although the water-soluble chalk appears, the dust is small, but it contains a large amount of organic solvents, which is harmful to the environment and human health. remove. Contents of the invention [0003] The invention provides a low-cost light chalk, which is not easy to drop powder, has small specific gravity, is convenient for writing, is durable, does not contain organic solvents, and is harmless to the environment and human health. [0004] A kind of low-cos...

AI Technical Summary

Problems solved by technology

[0002] Dust-free chalk is an improved product of ordinary chalk. It refers to the elimination of chalk dust pollution in classrooms. It just adds oil or polyalcohol to ordinary chalk as a binder, and then adds fillers with a larger specific gravity, such as clay and marl. Rock, cement, etc., increase the proportion of chalk dust, and writing is laborious. In addition, although the water-soluble chalk appears, the dust is small, but it contains a large amount of organic solvents, which is harmful to the environment and human health. remove