Application method of solvent type polymethacrylate pressure-sensitive adhesive

Abstract

The invention relates to an application method of a solvent type polymethacrylate pressure-sensitive adhesive. The method comprises the following steps: step 1, preparing adhesive diluent from a solvent type polymethacrylatepressure-sensitive adhesive and a solvent; step 2, dissolving a water reducing agent of which the mass percentage accounts for 0.5 percent to 5 percent of the dry weight mass of the solvent type polymethacrylate pressure-sensitive adhesive with the solvent, then adding into the adhesive diluent; steps 3, mixing an isocyanate curing agent with the solvent, adding into the adhesive diluent; step 4, adding a catalyst of which the mass percentage accounts for 0.01 percent to 1 percent of the dry weight mass of the solvent type polymethacrylate pressure-sensitive adhesive into the liquid prepared in the step 3, and obtaining adhesive coating liquid; step 5, adding a volatile organic acid substance which accounts for 1 percent to 5 percent of the dry weight mass of the polymethacrylate pressure-sensitive adhesive into the adhesive liquid under a state of being stirred; step 6, coating a substrate surface with the adhesive coating liquid, and performing solvent removal, solidification and post curing in an oven, so that an adhesive product is obtained.

Description

technical field [0001] The invention relates to the field of pressure-sensitive adhesive products, in particular to a method for using a solvent-based polyacrylate adhesive used in a humid environment. Background technique [0002] Pressure-sensitive adhesive products can exhibit viscosity without heating or using solvents, and are widely used in die-cutting, electronics, medicine, optics, electroplating protection, and material processing. Among them, solvent-based polymethacrylate adhesives have expanded the scope and field of use due to their excellent bonding performance, good electrical performance, excellent weather resistance, convenient preparation, and good economy. [0003] Isocyanate curing agents are widely used in polymethacrylate adhesives. The advantages of isocyanate curing agents are good curing performance and fast curing speed, but they are easily affected by moisture in the environment. The moisture remaining in the adhesive, diluent and air will prefere...

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Problems solved by technology

[0003] Isocyanate curing agents are widely used in polymethacrylate adhesives. The advantages of isocyanate curing agents are good curing performance and fast curing speed, but they are easily affected by moisture in the environment.

The moisture remaining in the adhesive, diluent and air will preferentially react with isocyanate and release carbon dioxide gas, which will cause the surface of the coated adhesive product to appear cloudy or rough; when the air humidity is relatively high , the moisture in the air is more likely to enter the solvent. After reacting with the isocyanate curing agent, the generated carbon dioxide gas forms pinhole-like pores (commonly known as "needle holes") or bubbles (commonly known as "prickly heat") on the rubber surface, which seriously affects the The surface quality of the adhesive product may lead to the scrapping of the product; at the same time, because the moisture in the environment consumes a certain amount of isocyanate curing agent, the curing of the adhesive product is not complete, resulting in an abnormal increase in the viscosity of the adhesive product and a decrease in cohesion. Insufficient heat and weather resistance and residual glue and degumming

[0004] In view of the side effects of moisture in the environment on isocyanate curing agents, solvent-based polymethacrylate adhesive coating factories generally take measures to stop production in hot and humid weather to avoid losses, or add isocyanate to the coating solution. Polar solvents such as propanol to disperse the water and gather in the coating agent, but this can only partially reduce the occurrence of bad phenomena such as rough rubber surface, but it is still difficult to eliminate the haze phenomenon of the rubber surface, and the remaining in the rubber Polar substances with hydroxyl groups such as water and isopropanol still have to react with the isocyanate curing agent, resulting in unnecessary loss of the curing agent, which will still lead to incomplete cross-linking and curing of adhesive products, inconsistent viscosity, poor stickiness and The adverse effects of intrinsic properties such as poor temperature resistance are still difficult to overcome

If cooling and dehumidification in the coating workshop is used to improve the moisture content in the air, but on the one hand, the low temperature and dehumidification will cause an increase in energy consumption costs, and on the other hand, the dry coating environment will also cause static electricity in the coating station. Accumulative increase leads to fire accidents

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