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    Home > Coatings News > Paints and Coatings Market > Paint knowledge | why are bubbles and pinholes produced during spraying construction?

    Paint knowledge | why are bubbles and pinholes produced during spraying construction?

    • Last Update: 2020-04-03
    • Source: Internet
    • Author: User
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    Core tips: answer: the analysis of bubbles and pinholes produced in spraying construction is as follows: 1 Phenomenon: there are a lot of big and small bubbles on the coating surface first, and then the bubbles break or break when the paint film is ground to form a dense pinhole like small hole 2 Cause: there are gases (solvent vapor, water vapor, expanded air or other gases that can be mixed into the paint, such as carbon dioxide, etc.) in the coating to break through the coating and form bubbles, and then break or wear to form pinholes When the dry speed of the surface layer is slightly higher than that of the interior layer, when the surface layer has started to condense and the interior solvent or air is still evaporating, the surface layer of the coating will break through and form bubbles This is related to the following Paint agent, top 10 Chinese wall paint brands Recommended introduction: interior wall paint and exterior wall paint can achieve beautiful, clean and pleasant effects, but the effects in different environments are different, so the color of the paint will be different There are ten brands of Chinese paint, ten brands of global paint, ten brands of Chinese wall paint, and ten brands of Chinese paint, Famous trademark of Chinese paint and coating In private rooms, most of us choose according to our own personality, personal hobbies and living habits The younger generation will choose the interior wall paint with rich colors and bright colors, while the older ones will have some working experience Paint Home News: A: spray construction bubble, pinhole analysis is as follows: 1, phenomenon: in the coating surface first appear a lot of little bubbles, then bubble rupture or in the paint film grinding when the formation of dense pinhole like small holes 2 Cause: there are gases (solvent vapor, water vapor, expanded air or other gases that can be mixed into the paint, such as carbon dioxide, etc.) in the coating to break through the coating and form bubbles, and then break or wear to form pinholes When the dry speed of the surface layer is slightly higher than that of the interior layer, when the surface layer has started to condense and the interior solvent or air is still evaporating, the surface layer of the coating will break through and form bubbles This is related to the following conditions: too high viscosity of paint, one-time coating thickness, wood The conduit is thick and deep, the filling hole is not filled with air; the spraying air pressure is too high, too much air is mixed in the paint; the oil, dust, sweat and so on are attached to the surface to be coated, and the water around these unclean objects gathers; the temperature difference between the paint and the surface to be coated is too large; the diluent is not used properly, the curing agent is added excessively or the wrong curing agent is used; the coating environment temperature is too high or the relative humidity is too high; the lower coating is dry If the coating is not completely dry, the upper coating shall be applied and dried rapidly; if the coating is dried by heating, the temperature is too high, the time for the coating to stand before heating is not enough, the solvent is not fully volatilized, the paint itself brings bubbles, and the bubbles generated during mixing are not eliminated, etc 3 Troubleshooting: check the coating process conditions for the above reasons, adjust the appropriate viscosity of the coating, match appropriate amount of diluent and curing agent, control the thickness of the coating; do well in filling holes and sanding of the base material, eliminate the pollution of the base material; adjust the appropriate air pressure, reduce the air mixing; improve the working environment, control the appropriate temperature and humidity; properly lengthen the recoating time, so that The layer shall be fully dried; the paint shall be allowed to stand for 20 minutes and then be sprayed; when heating and drying the coating, control the standing time to make the solvent volatilize fully and then preheat the coating In addition, the following measures can be taken: that is to say, adding slow drying solvent into the coating can improve the drying condition of the coating Generally, the amount of slow drying solvent can not exceed 20% of the diluent The home of coating is focused on the news and coating of coating, diatom mud, paint coating, coating process, fire-resistant coating, diatom mud, paint coating, coating process, decoration knowledge and decoration effect map of fire-resistant coating,
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