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Sand material of wet sandpaper is generally silicon carbide, and paper base of it is usually kraft paper. There are also more high-end, such as imported sandpaper, its paper base is mostly latex paper. The characteristics of latex paper are good flexibility, stronger surface adhesion of sand particles, which makes sand paper more durable, more uniform particles, and better polishing effect.
The clearance between sand grains of waterproof abrasive paper is small, and the debris produced by sandpaper is small. When used with water, the debris will flow out with the water, thus maintaining the sharpness of the sandpaper surface. If water sandpaper is used for dry grinding, the product debris will adhere to the gap between the sand grains, which will make the surface of sandpaper lose sharpness without grinding force. Thus, it can not achieve the effect of its use.