Research On Raw Lacquer Refining And Transparent Lacquer Preparation Process

Lacquer is a natural paint extracted from the bark of the sumac tree(Toxicodendron vernicifluum).Lacquer has excellent characteristics such as wear resistance,acid resistance and corrosion resistance,but there is a problem that the paint film is difficult to cure.At present,the research of modified paint is mainly used in the fields of chemical industry and shipbuilding,while there is less research on modified paint in traditional lacquer art.In order to improve the efficiency of lacquerware production,the refining process of raw lacquer and the preparation process of transparent lacquer were studied,and green environmentally friendly materials were used for experiments.The raw lacquer was refined by repeated ripening(heating and stirring at the same time)to prepare refined paint L1,L2,L3 and L4;On the basis of refined paint,36 kinds of transparent lacquer were prepared by mixing tung oil,linseed oil and turpentine with four refined paints in the ratio of 10%,30% and 50%.The paint plate coated with refined paint and transparent lacquer is dried in a dryer at 25°C and 80% humidity,and the drying time of the paint film is recorded;The characterization methods of microstructure,light transmittance,infrared,hardness,roughness and gloss were studied,and the following conclusions were drawn:1.In the study of the preparation process of refined paint,the dryness of refined paint will vary to different degrees due to the different refining times,among which the drying ability of refined paint L2 is the best;The hardness of the four refined lacquers is the same;With the increase of refining times,the roughness and gloss of the paint film will increase,while the pores and impurities on the surface of the paint film will decrease;The largest light transmittance is refined paint L1,with a maximum light transmittance of 89%;Oxidation and polymerization reactions occur continuously during the refining process of raw lacquer,so functional groups such as phenolic hydroxyl groups and dienes in the refined lacquer are constantly decreasing.2.The type of dry oil,the content of oil and the type of refined paint are all important factors affecting the dryness of transparent paint film and the quality of paint film.Turpentine modified transparent paint has the best dryability and physical properties,among which the drying time of transparent paint 2-10-S(10% turpentine modified refined paint L2)is the shortest,the roughness of 2-50-S(50% turpentine modified refined paint L2)is the smallest,and the gloss of 4-10-S(10% turpentine modified refined paint L4)is the largest.From the microstructure point of view,flax oil can reduce the number and diameter of pores on the surface of the paint film,while turpentine can improve the surface flatness of the paint film well.The light transmittance of tung oil modified transparent paint is significantly larger.The more oil content in the transparent paint,the worse the dryness of the paint film,the smaller the hardness and roughness,the greater the gloss,the better the microstructure and light transmittance.The transparent paint prepared by refining paint L2 has good dryness,and the refined paint L3 can prepare transparent paint with better light transmittance.Infrared data show that molecules such as tung acid,α-linolenic acid,α-pinene and β-pinene in tung oil,flax oil and turpentine can better promote the oxidative polymerization of refined paint.3.The best raw lacquer refining process in the experiment is refined lacquer L2,and the best transparent lacquer preparation process is transparent lacquer 2-10-S.Using these two types of lacquer creation,it was found that the drying time of the paint film of the deborn lacquerware can be shortened by 20%,while the production time of screw paint can be reduced by 35%.This is of great significance to improve the work efficiency of lacquer art and promote the development of lacquerware.