Food can inner wall coating and preparation method thereof

Abstract

The invention provides an inner wall coating of a food can. The coating is prepared from the following components in percentage by weight: 70-90% of cationic water-based epoxy resin, 10-30% of a phenolic resin curing agent, 0.1-0.3% of a flatting agent and 0.1-0.3% of a defoaming agent, wherein the cationic water-based epoxy resin is prepared from the following components in percentage by weight: 50-70% of epoxy resin, 25-45% of glycol ether, 2.5-7.5% of normal butanol, 1-5% of ethanol amine and 0.5-3% of glacial acetic acid; the phenolic resin curing agent is prepared from the following components in percentage by weight: 50-60% of phenolic resin, 40-50% of alcohols and 0-10% of closed isocyanate. Compared with the prior art, the coating provided by the invention has the beneficial effects that the adverse effect of the coating on the food quality is effectively reduced; the coating is relatively low in curing and forming temperature, relatively less in energy consumption and relatively high in safety performance and environment-friendly performance.

Description

【Technical field】 [0001] The invention relates to the technical field of coatings, in particular to a food can inner wall coating and a preparation method thereof. 【Background technique】 [0002] With the development of the canning industry, food cans have been widely used. Most of the food cans are metal cans. Since there are many kinds of food in the cans, if the food directly contacts the inner wall of the food cans, it is easy to react, resulting in a decline in the quality of the food in the cans, which in turn leads to safety and hygiene problems. At present, the more effective treatment method is to coat a layer of paint on the inner wall of the food can to avoid direct contact between the food and the inner wall of the food can. [0003] In the related art, the main components of a coating for the inner wall of a food can include phenol, formaldehyde, ammonia water, triethylaluminum and butanol. Because formaldehyde is easy to have residues in the preparation proce...

AI Technical Summary

Problems solved by technology

Since formaldehyde is easy to remain in the preparation process of the coating, and the coating is easy to volatilize harmful gas due to the existence of formaldehyde when the coating is solidified and formed into a film, which will easily lead to a decline in food quality, damage the health of consumers, and pollute the environment.

The main components of another food can inner wall coating include cyclohexanone and butyl acetate. Cyclohexanone and butyl acetate have a pungent smell, and cyclohexanone is a toxic substance, which causes safety and environmental problems.

Moreover, the curing temperature of the coating on the inner wall of the food can is relatively high, and it needs to be baked continuously for 15 to 20 minutes at an environment of 200 ° C to 205 ° C, so its energy consumption is also high

Therefore, the food tank inner wall coating of the related art has the disadvantages of easily leading to a decline in the quality of the food in the tank, high energy consumption, low safety performance and environmental protection performance.

Images