Preparation method and construction method of low-viscosity thick-coating type solvent-free epoxy drinking water tank paint

Abstract

The invention belongs to the technical field of epoxy drinking water tank paint, and relates to low-viscosity thick-coating solvent-free epoxy drinking water tank paint and a preparation method and aconstruction method of the low-viscosity thick-coating solvent-free epoxy drinking water tank paint. According to the paint, liquid epoxy resin, an active diluent, a pigment filler, an auxiliary agentand a phenolic aldehyde amine curing agent are used as components. The liquid epoxy resin is bisphenol A liquid epoxy resin or/and bisphenol F type liquid epoxy resin, the reactive diluent is a monofunctional reactive diluent, and by optimizing the components, the finally prepared thick-coating solvent-free epoxy drinking water tank paint does not need to be diluted by additionally adding a diluent during construction, and the thickness of a dry film coated at one time is greater than or equal to 300 microns. After construction, the coating can be quickly dried at a low temperature, sagging caused by long-time non-drying is avoided, the thick coating can be promoted to have excellent adhesive force, chemical corrosion resistance, salt spray resistance and the like, the requirements of drinking water hygienic indexes and toxicological indexes can be met while the service life is prolonged, and the coating has positive significance.

Description

technical field [0001] The present invention relates to a coating paint, in particular to a food-grade anti-corrosion paint for the inner wall of drinking water tanks, which is suitable for drinking water tanks, ballast water tanks, drinking water storage tanks, drinking water tanks, inner walls of drinking water pipelines, etc. Formulation of epoxy coating for anticorrosion protection, its preparation method and application method. Background technique [0002] With the rapid development of the world economy, shipbuilding and other industries are also developing rapidly. In order to keep up with the modern concept of environmental protection and green, product technology must be upgraded as soon as possible. A ship is a special means of transportation that sails in various seas around the world. It is subjected to a marine climate and corrosion environment that is many times harsher than that of land. Moreover, due to its different structures and functions, the functions of...

AI Technical Summary

Problems solved by technology

The cabin can be classified as a confined space. General solvent-based coatings are applied in a confined space. If there is no effective ventilation, the volatilization of organic solvents will easily cause safety production accidents.

In the short term, the organic solvent in the paint film cannot be completely volatilized, and the residual organic solvent will also have a certain adverse effect on the performance of the paint film and the water quality after water pressure

[0005] 2) One-time thick coating is prone to sag problem

Solvent-free paints are very slow to surface dry, and generally take more than 2 hours to dry to the surface. During this time, the one-time thick paint is easy to sag without drying for a long time;

[0006] 3) The viscosity is high, so it cannot be applied directly

It is often necessary to add diluent for proper dilution during construction, which cannot achieve low VOC emission standards;

[0007] 4) The problem of inability to construct under low temperature and high humidity environment

Generally, the curing reaction speed of high-solid and solvent-free epoxy coatings is too slow at low temperature or the paint film is prone to oil surface phenomenon under high humidity conditions, which causes problems of sticking back and interlayer adhesion.

The temperature is low and the humidity is high, usually auxiliary heating equipment or dehumidification equipment is required, which consumes a lot of manpower and material resources

Slow curing reaction and sticking back will also affect the appearance quality of the film under low temperature and high humidity, causing problems such as poor water quality after water pressure, yellowing of the paint film, and inability to recoat, and interlayer adhesion problems that cannot be recoated will affect Late repair and touch-up problems, resulting in overcoat peeling

[0008] At present, in order to solve the problem that the solvent-free epoxy drinking water tank coating is applied at low temperature in winter, the viscosity increases sharply, the reaction speed is slow, and the hardening time is long, so it is difficult to adapt to the actual coating process requirements.

In the Chinese patent CN201010616731.0 low-temperature quick-drying solvent-free epoxy drinking water tank coating and its preparation method, what is added is a tertiary amine catalyst K-54 and a curing agent to react together, although the reactivity and hardening and drying speed of the coating are improved, but the time is greatly shortened. The activation period is shortened, which increases the difficulty of actual construction

CN201310416385.5 A fast-curing environment-friendly epoxy coating for drilling water tanks and its manufacturing method. Although it is a solvent-free epoxy, it contains zinc chrome yellow, which does not meet the drinking water hygienic and toxicological indicators, and has not been studied Drying and curing conditions in the thick coating state, and its salt spray resistance is also difficult to meet the requirements of the naval coating performance specification of not less than 2000h

[0009] In view of the fact that the existing solvent-free epoxy drinking water tank paint cannot be used for direct construction without diluent, VOC emission is difficult to be lower than 100g / L, the dry film thickness of one-time construction is less than 300 microns, and low temperature and high humidity cannot be applied. Problems such as direct recoating without sanding

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