How to correctly select the water-like wood paint with desiccant

In recent years, due to the increasingly strict domestic environmental regulations, water-based wood paint development is rapid, while water-based wood lacquer technology innovation, development and maturity, but also make this kind of environmental protection technology has been widely used.
the production and construction process of
-based wood paint will introduce air and create bubbles, and during the coating of the paint film, bubbles in the substrate void will be replaced. Water-like wood paint contains surfactants that promote and stabilize bubbles

. Anti-foaming and de-foaming are always things to be done in the production, construction and even film drying process of water-like wood paint.
▏ deblistering agent should have the following characteristics:
✪ de-foaming agent surface pressure should be less than the surface pressure of the need to de-bubble liquid;
✪ in the need to de-bubble liquid solubility should be as small as possible;
✪ should have good dispersion and strong diffusion,
✪ can not react with the liquid to de-foam, can not affect the stability of emulsion, resin,
✪ de-foaming long-lasting.
▏ a good desiccant should have both blistering and breaking effect:
✪ anti-bubble effect: in the high-speed dispersion, shearing process, can inhibit the production of bubbles, and can gather and eliminate small bubbles, so that bubbles increase the rate of rise
✪;
✪ good desiccant should also have a long-lasting deblistering capacity.
▏ the main components that make up the defrosting agent are:
✪ carriers, extenders - mineral oils, paraffins, oxygenated oils, natural oils, fatty alcohols
✪ surfactant molecules absorbents - waxes, soaps, amino compounds, hydrophobic silicon dioxide
✪ mechanical damage foam wall layer, but also Adsorbents for extenders and surfactants - silicone oil, modified silicone oil
✪ regulatory compatibness - non-ion surfactants
performance factors for desmoulators in water-based wood paints
The performance of desiccant is analyzed in detail between the following, and the factors affecting the performance of desiccant are discussed.
▏ defoulant product selection:
in the construction facilities paint work, usually according to the type of wood paint, targeted selection of defoulant, can play a very good inhibitory role, to ensure the smooth completion of the paint work.
such as the gloss requirements are not high primer, putty, etc. , you can choose mineral oil desobbists, not only save costs, but also play a synchronous de-foaming role.
For polyurethane emulsion system of water-based wood paint and high-gloss, transparent requirements of the paint, usually using silicone resin-type defrosting agent, this defrosting agent only a small amount, can significantly inhibit foam production, and inhibition will last a long time, but also does not affect gloss and system transparency requirements.
these desiccants are used reasonably in different paint environments to ensure that the construction tasks are completed on schedule and bring good economic benefits.
▏ effects of the water-based resin's own emulsifier
the wood paint itself is used in the preparation process, which is a necessary material for production, but this can also lead to foam production.
the properties of wood paint make it chemically resistant to all types of desiccants, some of which function differently even in the same type of water-based resin.
so the selection of desiccant should be combined with the experience of the use of previous projects to analyze, to ensure the efficiency of the project.
▏ Effects of surfactants
Due to the high surface temperature of water at room temperature and the fluid properties of the water-based wood paint itself, in order to ensure the stability of the internal structure, some surfactants such as wetting agents and dispersants need to be added to the preparation of wood paint.
these reagents in the solid wood lacquer film structure at the same time, itself with foaming properties, invisibly increase the difficulty of deblistering, in the selection of these reagents should also try to choose non-foaming materials.
study found that glycol surfactant is a better performance surfactant, which has both wetting and foam control effect, reducing surface pressure and controlling foam, but also simplified the formulation of wood coating.
▏ viscosity and pH
the viscosity of the wood paint itself also affects the effectiveness of the desiccant, making it difficult to eliminate bubbles.
when the viscosity of the coating is high, the bubbles formed by the internal gas are difficult to move, it is not easy to flush out the surface of the paint body, resulting in the foam is not easy to eliminate.
study found that
(1) As the pH increases, the viscosity of latex paint increases gradually, and the greater the pH, the faster the viscosity increases.
(2) the viscosity of the paint has a certain effect on the foaming of the paint film, when the viscosity of the paint material is 9 mPa.s, the paint film is shown to be free of micro-bubbles without foaming state, and has a flowing phenomenon
;
the pH inside the paint, the easier it is to increase foaming.
▏ of the production process
when the water-based wood paint is produced, the addition method and dose of defrosting agent, the effective reaction rate, will affect the effect of foam suppression.
So the selection of desiccant should be considered comprehensively from its performance, not only to consider whether the desiccant and wood paint compatible and non-exclusion, but also to consider its addition method and dose and other comprehensive factors, in order to really let it play its due role.
▏ other factors
water-powered wood paint has very high process requirements, not only the construction of the appropriate temperature, on-site practitioners should also master skills, so that wood paint to play the best performance.
when the field operating temperature is high, wood paint will dry quickly after coating, the process of foaming is difficult to eliminate quickly, and different construction processes also have a great impact on the effect of coating.
preparation of a water-based wood two-in-one white paint, and the use of traditional technology and water-based wood two-in-one construction process for coating.
compared with traditional technology, two-in-one white paint only needs one paint material can be directly constructed, and has the same coating effect, which brings great convenience to the construction.
Summary
In summary, in practical applications, we need to pay attention to the following points:
(1) according to different paint environment and experience, reasonable use of defoaming agent
(2) in the selection of reagents, to try to choose non-foaming materials
(3) to control the pH inside the paint
(4) related enterprises to increase the training of coating technology, to ensure that professional and technical staff can master the coating process, strengthen their skills, so that wood paint and foaming agent can play its due role, to ensure the aesthetic
of the building facilities