Uneven coating
1. Part of the adhesive in the glue tank solidifies. Replace or add new adhesive.
2. Low compound pressure. Compound pressure should be increased.
3. Swelling and deformation of cots. Replace the rubber roller.
4. The thickness tolerance of plastic film is large. The film shall be replaced
and the film with small thickness tolerance shall be selected.
5. Film relaxation. The traction should be adjusted.
Wrinkle film
1. The film transfer roller is unbalanced. The transfer rollers should be adjusted.
2. The tightness of both ends of the film is inconsistent, with wavy edges. The
qualified film shall be replaced in the book
printing.
3. The adhesive layer is too thick and the solvent evaporation is not complete,
which affects the viscosity of the adhesive. It is squeezed by the pressure
roller and slides between the paper (printed matter) and the film. The gluing
amount shall be adjusted to increase the drying channel temperature
4. The two ends of electric heating roller and rubber roller are uneven, the
pressure is inconsistent, and the linear speed is not equal. Both rollers shall
be adjusted
5. Insufficient tension will cause uneven film speed, which will cause film
wrinkling. The pressure should be adjusted to make it normal.
6. If the surface of the coating layer on the film is not completely dry, it will
also cause the film to wrinkle. It can be solved by increasing the drying
temperature.
7. The temperature is too high, causing the film to wrinkle when feeding. In the
film coating process, the purpose of heating is to soften the film and bond the
paper with the plastic film. Therefore, the fan should be used for cooling, and
the electric heating wire or other heating equipment should be turned off to
restore the temperature to normal as soon as possible.
Corrugated paper
Coated
paper is generally coated paper, offset paper and whiteboard. The paper
wrinkling occurs when laminating. Generally, there are the following
situations.
1. Improper temperature and humidity control in the workshop. When the relative
humidity is too high, the paper absorbs moisture and has a "lotus leaf
edge", resulting in paper wrinkling in the film covering process of book printing. The temperature and
humidity of the workshop must be strictly controlled.
2. If the ambient temperature is too high or the coating temperature is too high,
the paper will tighten and wrinkle. The pressing plate can be used to flatten,
increase the times of knocking and kneading the paper before laminating, and
reduce the environment and laminating temperature.
3. Uneven roller pressure causes paper wrinkling during film covering. In this
case, the pressure shall be corrected first, and then the machine shall be
started for operation.
4. If the cots are uneven, resulting in paper wrinkling in the lamination, replace
them with new cots or grind the old cots flat for reuse.
5. There is dirt on the cot, which causes the paper to wrinkle when laminating.
The cot should be cleaned in time to keep it clean.