Common Issues in the Production and Use of Heat Transfer Films

　　 Heat transfer film During production and use, several issues frequently arise, including incomplete pattern transfer, reduced transparency of the release‑coated base film, off‑odors in the transfer film, and poor adhesion of transferred text. This paper provides a detailed analysis of the causes and corresponding countermeasures for these common problems encountered in the manufacturing and application of thermal transfer films.

　　(1) Incomplete pattern transfer

　　Possible causes include: 1. Uneven coating of the transfer rubber; 2. Non-uniform hardness or scratches on the copier’s drum; 3. Low transfer temperature. Corresponding corrective measures are: inspect the adhesive coating and check whether the feeder screen is clogged; replace the rubber roller; increase the temperature.

　　(2) After applying the release coating, the transparency of the base film decreases.

　　The possible causes are: 1. Excessive adhesive application; 2. Rough surface of the adhesive film. Corresponding corrective measures include: reducing the amount of adhesive applied and optimizing the temperature gradient in the curing oven.

　　(3) Heat transfer film Has an unusual odor.

　　The possible causes are: 1. Insufficient evaporation of solvents in the adhesive; 2. Excessive residual solvents in the ink. Corresponding corrective measures: adjust the curing temperature and production speed; adjust the oven temperature and production speed of the printing press.

　　(4) The transferred print has poor adhesion.

　　The cause may be poor compatibility between the transfer rubber and the substrate. The corresponding corrective measure is to select a different transfer belt.

　　(5) The transferred text exhibits poor chemical resistance.

　　The cause may be that the release rubber used has poor corrosion resistance. Corresponding countermeasures include modifying the release rubber or selecting a different release rubber.

　　(6) Matte or pearlescent effects do not meet the requirements.

　　The cause may be that the pulp ratio has not been adjusted. Corresponding corrective measures include: readjusting the pulp ratio and reselecting the fineness of the pearl powder.

　　(7) Deformation of the printed halftone dots

　　The cause may be poor temperature resistance of the ink. The corresponding solution is to select an ink with superior temperature resistance.

　　(8) Self-adhesive thermal transfer film

　　The possible causes are: 1. Solvents in the adhesive or ink have not fully evaporated; 2. The adhesive has a low softening point. Corresponding solutions include: 1. Raising the processing temperature to facilitate solvent evaporation; 2. Selecting an adhesive with a higher softening point.