Waterproof and oil-proof white cardboard and production method thereof

Abstract

The waterproof and oil-proof white cardboard comprises a surface layer, a core layer and a bottom layer, the bottom layer is sequentially coated with a bottom coating and a waterproof and oil-proof coating, slurry is subjected to internal sizing firstly, surface sizing is conducted on the surface layer and the bottom layer, and then the surface layer and the bottom layer are subjected to surface sizing; the waterproof and oil-proof coating is prepared from 30 to 40 parts of butyronitrile latex, 10 to 20 parts of silicone acrylic emulsion, 20 to 30 parts of oxidized starch, a starch cross-linking agent, 5 to 10 parts of paraffin emulsion, 0.5 to 2 parts of CMC (Carboxymethyl Cellulose), a preservative and a defoaming agent; the coating of the bottom coating comprises 100 parts of filler, 5-8 parts of carboxylic butadiene-styrene latex, 3-6 parts of biological latex, 1-4 parts of soybean protein isolate, 0.08-0.2 part of a water repellent agent and the like; the bottom layer sizing agent comprises 100 parts of enzyme modified starch and 8-13 parts of polyvinyl alcohol. The back surface of the white cardboard has excellent water resistance and oil resistance, the whiteness and smoothness of the back surface are improved, the overall stiffness of the white cardboard is improved, and the white cardboard is low in cost and relatively environmentally friendly.

Description

technical field [0001] The invention relates to the technical field of papermaking, in particular to a waterproof and oil-proof white cardboard and a production method thereof. Background technique [0002] White cardboard can be used as a packaging material to package a variety of items, including food. When used in food packaging, it is often required that the side in contact with food be waterproof and oil-proof. The side of white cardboard in contact with food is generally the back side, and the front side is used for printing patterns. . The front of ordinary white cardboard will be coated to make the paper have a certain surface strength and printability, which is convenient for printing. The back is often not coated or conventionally coated to improve whiteness and surface strength or reduce costs. When paper needs to be waterproof and oil-proof, the commonly used method is to coat a layer of polymer film on its surface in the form of a coating, or to apply an oil-re...

AI Technical Summary

Problems solved by technology

When paper needs to be waterproof and oil-proof, the commonly used method is to coat a layer of polymer film on its surface in the form of a coating, or to apply an oil-repellent agent. The former is difficult to break down and degrade due to the polymer film, which will cause the paper material to recycle. It is difficult to pulp and pulp after use, which affects the recycling and natural degradation of paper; the oil repellents coated with the latter are mostly fluorine-containing oil repellents, but fluorine-containing compounds have potential safety hazards and endanger human health. Existing regulations prohibit its use, so there are safety concerns when fluorine-containing oil repellents are used in direct contact with food, and it is an inevitable development trend to find alternative products or solutions

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