In recent years, due to the increasingly strict domestic environmental protection regulations, water-based wood paint defoamer has developed rapidly. At the same time, the innovation, development and maturity of water-based wood paint defoamer technology have also enabled this environmental protection technology to be widely used.

The production and construction of waterborne wood paint defoamer will introduce air and generate air bubbles; during the coating process of the paint film, the air bubbles in the voids of the substrate will be replaced.

Surface-active substances contained in waterborne wood coatings promote and stabilize air bubbles.

Defoaming and defoaming are always a must in the production, construction and drying process of waterborne wood paint defoamers.

The defoamer should have the following characteristics:

The surface tension of the defoamer is less than the surface tension of the liquid to be defoamed;

The solubility in the liquid to be defoamed should be as small as possible;

Has good dispersibility and strong dispersing ability;

It cannot react with the defoamed liquid, nor will it affect the stability of the emulsion and resin;

Has good defoaming durability.

A good defoamer should have both defoaming and defoaming effects:

Anti-foaming effect: in the process of high-speed dispersion and shearing, it can inhibit the generation of bubbles, and can coalesce and eliminate small bubbles, so that the bubbles can increase the rising speed;

Bubble burst effect: can burst the generated bubbles, usually larger

A good defoamer should also have long-lasting defoaming ability.

The main components of the defoamer are:

Carriers, Extenders - Mineral Oils, Paraffins, Oxidized Oils, Natural Oils, Absorbers for Fatty Alcohol Surfactant Molecules - Waxes, Soaps, Amino Compounds, Hydrophobic Silicas

Mechanical destruction of the foam wall layer. It is also an adsorbent for fillers and surfactants - silicone oil, modified silicone oil

Adjusting Compatibility - Nonionic Surfactants

Factors affecting the performance of defoamer in water-based wood paint defoamer

Due to its liquid nature, the defoamer penetrates quickly into all layers of the wood lacquer to completely defoam.

The following is a dedicated study and analysis of defoamer performance, discussing the factors that affect defoamer performance.

Selection of defoamer products:

For construction work, defoamer is usually selected according to the type of wood paint used, which can play a good inhibitory role and ensure the smooth completion of the painting work.

For primers and putties that require low gloss, mineral oil-based defoamers can be selected, which not only saves costs, but also provides defoaming effects.

For polyurethane emulsion systems, waterborne wood paint defoamers and high topcoats requiring gloss and transparency, silicone resin defoamers are usually used. This defoamer can significantly suppress the generation of foam and inhibit the

It will last a long time without compromising gloss and system clarity requirements.

These defoamers are used reasonably in different coating environments to ensure that construction tasks are completed on time and bring good economic benefits.

Influence of water-based resin self-emulsifier

The wood varnish itself uses an emulsifier in the preparation process, which is a necessary material for manufacturing, but this also leads to the formation of foam.

The properties of wood lacquer allow it to chemically react with various defoamers. Some defoamers have different functions even within the same type of waterborne resin.

The choice of defoamer should be analyzed in conjunction with the experience of previous projects to ensure the efficiency of the project.

The effect of surfactants

Due to the high surface tension of water at room temperature and the fluidity of water-based wood paint defoamer itself, in order to ensure the stability of the internal structure, some wetting agents, dispersants and other surfactants must be added when preparing wood paint.

These agents not only stabilize the structure of the wood paint film, but also have the characteristic of foaming, which actually increases the difficulty of defoaming. When selecting these reagents, materials that are not easy to foam should be selected as much as possible.

The study found that acetylene surfactant is a better performance surfactant. They provide wetting and foam control. It also simplifies the formulation of wood coatings while reducing surface tension and controlling foam.

Influence of Viscosity and pH

The viscosity of the wood coating itself will also affect the effect of the coating. Defoamer, difficult to eliminate air bubbles.

When the viscosity of the paint is high, the bubbles formed by the internal gas are difficult to move and are not easily flushed out of the paint

1 The study found:

1. With the increase of pH value, the viscosity of latex paint gradually increases, and the higher the pH value, the faster the viscosity increases.

2. The viscosity of the paint has a certain influence on the foaming performance of the paint film. When the viscosity of the coating is 9mPa·s, the coating film is in a state of no micro-bubble, no foaming, and has a sagging phenomenon;

3. When the viscosity of the coating gradually increases to 14mPa·s, the coating film begins to bubble from a small amount of micro-bubbles to a large number of micro-bubbles, and will not sag.

Therefore, the higher the pH inside the paint, the easier it is to increase foam.

The impact of the production process

In the production process of the water-based wood paint defoamer, the method, the amount of the added defoamer, and the effective reaction rate will affect the foam suppression effect.

Therefore, when choosing a defoamer, its properties should be considered, not only whether the defoamer is compatible with wood. Coatings, but also comprehensive factors, such as adding methods and dosage, to make it really play its due role.

Effect. ##other factors

The water-based wood paint defoamer has high requirements on the process. Not only does it need a suitable temperature during the construction process, but also the on-site practitioners must master the skills to make the wood paint perform at its best.

When the working temperature on site is high, the wood paint will dry quickly after painting, and it is difficult to quickly eliminate blistering during processing;

Prepared water-based two-in-one white paint for wood, and developed water-based two-in-one construction technology.

Compared with the traditional process, the two-in-one white paint can be directly applied with only one paint, and has the same coating effect, which brings you great convenience.

All in all, in practical applications, we need to pay attention to the following points:

1. Reasonable use of defoamer according to different paint installation environments and experience

2. When choosing reagents, try to choose materials that are not easy to foam

3. To control the pH value inside the paint

4. Relevant enterprises should increase the training of coating technology to ensure professional skills

Technicians can master the spraying process and enhance their skills so that wood coatings and foaming agents can do their job well to ensure the aesthetics of the building.