Modified dry oil alkyd resin for protective paint for metal coating on the back of the mirror and the curtain coating paint

Abstract

The modified drying alkyd resin for curtain coated paint protecting metal coating in the back of mirror includes medium oil content drying alkyd resin in 55-70 wt%, acrylate monomer in 20-30 wt% and epoxy resin as modifier in 10-15 wt%. The medium oil content drying alkyd resin and the acrylate monomer form copolymer resin, and the copolymer resin is reacted with epoxy resin to form the modified drying alkyd resin with final viscosity of 150-300 s, acid value lower than 5 mg KOH/g and solid powder content over 50 wt%. The modified drying alkyd resin, selected cross-linking resin, pigment and solvent constitute curtain coated paint capable of well attaching to the surface of smooth metal coating.

Description

technical field [0001] The invention relates to a modified dry oil alkyd resin and a curtain coating for a mirror back metal coating protection coating. Background technique [0002] There are two production methods for mirrors: one is to deposit a layer of aluminum on the glass surface as a reflective layer by vacuum aluminum plating. The second is to first coat a layer of metallic silver on the glass surface as a reflective layer by chemical methods, and then use chemical methods to coat a layer of copper on the silver film to increase the reflection effect and protective effect of the silver film. Since the metal layer of the mirror is easily eroded by atmospheric pollution, and the use environment is mostly in places with high humidity, large temperature difference, and strong corrosion, the metal layer is easily corroded and tarnished, resulting in loss of optical properties. In order to make the metal layer on the back of the mirror less susceptible to chemical corros...

AI Technical Summary

Problems solved by technology

Although the prepared coating film has fast drying, high hardness and excellent water resistance, due to the high toxicity of TDI, it is easy to leak during feeding, which will pollute the environment and affect human health

Secondly, it is difficult to achieve large-scale production because of gelation if there is a slight carelessness in the production process of TDI modified alkyd resin.

Furthermore, TDI is more expensive, and the cost of use is higher

[0004] Mirror back protective paint such as CN1371409A discloses " based on the quick-drying type high solid content paint of modified alkyd resin ", is a kind of composition of acrylic modified alkyd resin normal temperature curing high solid, has good performance, because The coating structure is not dense enough, and chemical substances are easy to penetrate, which affects the durability of the mirror back reflection layer

[0005] To sum up, the current film-forming resins used in mirror back coatings all have the defect of single performance, especially when they are used in the curtain coating process, they are affected by factors such as glass temperature, drying time, and the continuous running line speed of the glass. It is more difficult to keep the thickness of the coating wet film uniform, adjustable and not bifurcated