Asked by water-based paint experts: water-based paints appear flocculated in the production process Problem: Our company produced a batch of waterborne paint last week. The formula remains unchanged. After the completion of production, the coating appears a mass flocculent,it is  difficult to remove the filtration, the quality of waterborne coating is reduced. What is the cause? What method can purify? Answer: There are several reasons for the appearance of mass floccus in the production process of coating: 1.The most common is the dispersion of pigments and fillers, and flocculation clumps appear when film additives are added in the conditioning process.The flocculating clumps remain in the paint and are difficult to remove by filtration. 2.Coating production in the thickening process, thickener concentration is high, add too fast, cause local violent thickening, become granule:especially alkali swelling thickener cellulose ether thickener added directly easy to lead to the appearance of the mass. 3.Combination of cellulose ether thickeners and some whitening agents, such as hydroxyethyl cellulose (HEC) and whitening agents, will lead to flocculation clumps, leading to filtration difficulties. Solution: Film forming additives cause flocculation of pigments and fillers,Most occur in low PVC varnish systems(Particle Volume Concentration).Low PVC coating systems are often combined with low ion concentration of hydrophobic dispersant .Due to low PVC, high amount of polymer emulsion, relatively large amount of film forming agent,In the process of adding film forming agent, the solvent will peel the dispersant off the surface of the pigment and the filler to make the pigment and the filler flocculate.In order to avoid flocculation of the system, the film forming auxiliary agent can be preemulsified and then added. The pre-emulsifying composition of film-forming auxiliary can be referred to as the following proportions: film-forming auxiliary, about 5% cosolvent(ethylene glycol or propylene glycol, etc.), about 0.5% high HLB value wetting agent, and 50% ~ 80% water, a total of 100%, which will be added evenly after mixing . For the dispersion that has caused flocculation, add wetting agent appropriately and then disperse at high speed, open the flocculation, and then adjust the paint normally. General wetting agent accounts for about 0.2% of the total amount of paint. The flocculation caused by too fast and too thick thickening agent can be prevented by changing the adding method .For high molecular weight cellulose ether, alkali swelling (ASE) or hydrophobic modified alkali swelling (HASE) thickeners, can be made into a certain concentration of pre-gel, pre-gel form can be added at any stage.Cellulose ether thickening agent can also be added in advance in the process of dispersing color filler, so that the thickening agent is fully dissolved in the coating . Alkali swelling (ASE) and hydrophobic modified alkali swelling (HASE) thickeners can be d...

Asked by water-based paint experts: water-based wood lacquer wood grain display is not clear enough Question: Our company is now doing the first coat of wood lacquer and tried a water-based resin (polyurethane). and there is no problem with the adhesion.The current problem is that after adding color essence, it is applied to the floor and the wood grain display is not clear enough. The amount of the water-based resin is 90%, less than 90%, and the surface wood grain of the board is not enough. The solvent used now is PM and BCS, and no water is added. I wonder why? I hope the experts can give some advice. Answer： Mr. Jiang, thank you for your question. There is no problem with the PM in your recipe. The problem you encounter may be caused by several reasons: 1.The resin you used is not wettable enough. This is because the polyurethane emulsion particles in your formulation system are larger in diameter than the holes in the wood. Accordingly, paint of waterborne wood implement is permeable difference, paint of waterborne wood implement cannot infiltrate the interior of lumber grain and enclothe in lumber surface, enclothe grain of lumber, abate the layering feeling of wood grain. 2.The film forming agent you use may not be compatible with the emulsion you choose. Film forming agents, or BCS, are selective for emulsions. This is because waterborne resin manufacturers control the phase structure of waterborne resin through the selection of monomer,the addition sequence, the use of surfactant amount and other technological conditions.The phase structure of waterborneresins is the technical secret of the emulsion manufacturer.However, suppliers will provide the recommended dosage forms and proportions of the aqueous tree fat they provide. This is why different water-based resins usually require different combinations of additives. In your formulation system, when the amount of water-based resins is higher than 90%, the compatibility problem of emulsion is not obvious because the amount of other additives is relatively small, and the wood grain is quite clear. On the contrary, in the case of the amount of water-based resin less than 90%, the amount of other additives relative increase, emulsion compatibility problems become obvious, wood grain also therefore appear "Board surface blur”. We suggest that you adjust the current resin varieties or film forming agent varieties. Among sinograce chemical customers, Water based wood paint are our ustomers to use High Solid Water -based Polyurethane Dispersion PU - 402 has good response.Or our Special resin polymer pf-136, with small particles, good permeability and little selectivity for film-forming additives, is also the acrylic resin for water-borne wood lacquer. visit us sinograce chemical: https://www.sinogracechem.com Get a Quote Now :sales@sinogracechem.com Telephone :+86 0551 63459511

Common problems with water-based paint: oil slick surface of paint Problem: The finished product has floating black spots or impurities on the surface. A lot of coating produce technical personnel to had encountered similar problem, there is in coating production process "small bubble" or small black dot cannot eliminate. Carefully examine these "little bubbles" ~ they are actually small black oil spots. Under a 20x magnifying glass, a small white powder substance can be seen in the center of the oil dot. Analysis: Small black oil is usually brought in by the filler oil, change a batch of raw materials, small black oil problem disappeared. The application effect of finished coating with floating black oil spots is not good. Because the black oil spots are incompatible with the coating system, the oil spots embedded in the film become defects after the film is formed.Because black small oil dot is mixture of oil, pink, participate in coating to become film, its composition and coating other component are different, produce stress in besmear film dry process, bring about the besmear film around black small oil dot to contain smalf crack. Solutions: 1. For the finished coating with floating black oil dots, the base material wetting agent and an appropriate amount of emulsifier can be appropriately added to make the small black oil dots without tank capacity, like pigment particles, enter the paint system after absorbing the wetting agent and no longer affect the appearance of the coating and film. 2. Strengthen the quality control of raw materials. 3 In the paint formula, try to introduce hydrophobic dispersant, can prevent the occurrence of this problem. Sinograce Chemical co., LTD produces water based paint ，chemical additives for water based paint, such as defoaming agent, thickening agent, leveling agent, wetting agent visit us sinograce chemical: https://www.sinogracechem.com Get a Quote Now :sales@sinogracechem.com Telephone :+86 0551 63459511

Case study of water-based paint: the quality of water-based paint is unstable Maintaining the stability of waterborne coatings is one of the keys to the success of waterborne coatings manufacturers. This is especially important for manufacturers of industrial waterborne paints. There are many reasons for the unstable quality of water based paint, such as water-based paint process,water-based paint formula and water-based paint raw materials. Matter Jiangsu some coating company waterborne wood matte white finish quality is good, a few furniture factory use the effect is very good. However, there are always problems with recent products. Formula and raw materials remain unchanged. The manufacturerasks hua jinsi what is the problem that causes quality problem of water paint product, and how to make quality of water paint product stable. Scene investigation The professional technicians of Sinograce Chemical visited the factory in person and found that the quality of the water-based wood lacquer made just now was very good, and the inspection was no problem. However, after storage for a period of time, the product return coarse, adhesion is not good, poor hiding power, quality is not stable. Poor customer performance. Analysis No problem with formula data and process. It is preliminarily concluded that the problem lies in the raw materials of waterborne wood lacquer. Sinograce Chemical technicians conducted a series of comparative tests in the laboratory for several possible problems and soon found abnormalities in titanium dioxide. Dispersants have little effect on its dispersion. Scraper fineness shows wet film shrinkage, gloss is not normal, and fineness and qualified. As a result, particle agglomeration will occur in the finished product after a long time, and coarse return will be easy to appear, leading to the decline of adhesion and poor covering power. After determining the problem of titanium dioxide, huazinsi's professional and technical personnel carried out the verification experiment again, and the result proved that the problem was caused by the quality difference of titanium dioxide. After several batches of titanium dioxide in the modulation of water-borne wood matte white finish, the results are very good: smooth film, various performance indicators are up to the requirements. Solution Sinograce chemical suggested that the quality of titanium dioxide batch problems, guide customers to replace titanium dioxide varieties. Sinograce Chemical advised customers to further use the newly selected titanium dioxide storage stability test. A week later, the customer feedback sample is very good, excellent quality. Coating manufacturer has sent the product to furniture factory, response is good. Highlights of the case Manufacturers should usually pay attention to the detection of water paint raw material supply and quality. In the water paint product quality problems, and formula and process have not changed, to solve the problem from the water ...