Preparation And Study Of Properties Of High-temperature Resisted Water-Based Metallic Baking Paint

In this paper a kind of water-based metal baking paint with high decorative function andcapability of bearing high heat has been prepared and the various factors which affect theperformance of paints are studied. The whole paper includes two parts as follows:In the first part, a kind of water reducible amino baking paint has been prepared bychoosing of water reducible hydroxyl resin and amino resin curing agent, ascertaining theratio of them, assorting appropriate pigments/additives. The effect of type and amount ofwater reducible hydroxyl resin, amino resin, pigments, additives, conditions of usage on thewater dilution amino baking paint mechanical properties, gloss, the capability of bearing highheat and the degree of crosslinking. The experiment results show that, the glass transitiontemperature is about–19.6℃when using the acrylic-polyester resin as film-forming resin, thefilm’s impact50kg·cm, flexible<1mm, using whole methylated melamine resin as curingagent, the good performance paint has been prepared when acrylic-polyester/amino resin is8:1, paint’s pencil hardness is4H and perform well on resistance of water, solvent, salt-fogand moist-heat,3%reddish brown pearl powder which particle size is400mesh and1%modified cellulose acetate alignment agent bring high decoration and function of bearing highheat, the film can achieve excellent appearance and high degree of crosslinking under theseconditions that dry film thickness is between15μm to25μm, baking temperature is155℃and baking time is between20min to25min, it is well for saving energy consumption at thesame time.In the second part, according to the shortcomings of water-based flash baking paint in theprocess of production and construction, the influencing factors of paint particles blur,"pricklyheat", shrinkage, bubbles and other ills factors are systemically analyzed, and thecorresponding solutions is put forward from the point of formula design and process. Theresults show that suitable dispersant, the type and dosage of alignment agent, constructiontechnology and equipment can help reduce or even avoid the film surface roughness causedby particles; reasonable control of the painting room ambient temperature and humidity,combined with a suitable spraying and baking process can effectively reduce or even avoid blur phenomenon; the spraying viscosity is controlled in the range of15to25s, with10%ethylene glycol monobutyl ether as a co-solvent, then the "prickly heat" issues can beeffectively solved; suitable viscosity, film thickness, reasonable control of the dosage of thedefoaming agent and leveling agent can reduce or even eliminate film shrinkage; and madeuse of water and alcohols azeotropic liquid as a dispersion medium to control the moistureevaporation rate, combined with a suitable defoaming and wetting agent, can greatly reduce oreven eliminate the film bubbles.