Study On The Roller Coating Process Of Pigmented UV Lacquer For Medium Density Fiberboard

Taking the medium density fiberboard (MDF) as the substrate and the clear UV filler,white UV basecoat and white UV topcoat as the coating materials, this paper studied theinfluence of substrate surface treatment, process engineering of basecoat and topcoat, UVcuring technology on the coating film quality. A process route of MDF roller coating withpigmented UV lacquer was exploited, which offered a new environmental, economical andefficient method for MDF surface finishing. The main work and results have been listed asfollows:1. According to the result of the single and double factor test, the influence of substratesanding and filler application on the quality of the relevant coating film and the reasons wereanalyzed based on the variance analysis method. The optimal surface treatment of substrate is:fine sanding for the substrate with two cross sanding belt240#/240#, then do the fillerapplication twice, finally sand the filler film with cross sanding belt400#/400#.2. With comparative analysis, the optimal coating process of basecoat is:3times basecoat,application amount for each coat is12g/m2.3. According to the result of the orthogonal test, the influence of application amount,leveling temperature and time of topcoat on the quality of the coating film and the reasons wereanalyzed based on the range analysis method. The optimal coating technology of topcoat is:application amount22g/m2, leveling temperature50℃, leveling time45s.4. According to the result of the single factor test, the influence of UV radiation capacityfor basecoat on the quality of the coating film and the reasons were analyzed based on thevariance analysis method with suitable UV curing unit. The optimal UV radiation energy foreach basecoat is260mJ/cm2.5. The result of the comprehensive validation test based on the above mentioned coatingprocess parameters showed good quality of coating firm, which is flatness:0.39μm, adhesion:degree2, hardness:3H, gloss48.5gloss, and the result meets the requirement of IKEA R2standards. Moreover, in contrast of traditional finishing with spraying, the new solution saved70%of the total finishing cost. So the roller coating process with pigmented UV lacquer forMDF studied is a feasible and economical finishing solution for the relevant furnituremanufacturer.