Printing effect of writable kraft paper tape!

The following points should be paid attention to in offset printing of Eco friendly kraft paper tape

 

1. Hang air and adjust humidity before the printing of flat sheet writable kraft paper tape, remove the broken and uneven paper, and then clean up the dust and impurities on the paper surface, so that the temperature and humidity of the writable kraft paper tape are consistent with the temperature and humidity of offset printing workshop. In this way, the paper can be prevented from warping and scraping due to uneven moisture content. After the paper is hung in the air for humidity control, the paper splint is pressed on the paper stack, and compacted with iron plate and big stone to avoid the paper bulky and not solid.

 

2. Choose the right model. For the thicker writing kraft paper tape of more than 80g / m2, it is better not to print with small four or eight open offset press. Because the 80 g / m2 above writable kraft paper tape is thick, the suction nozzle often can not absorb the paper when feeding paper. In addition, due to the small size of the paper, it is easy to have double or multiple faults, or the paper skews on the paper board. The results show that when the offset press or full offset press is used to print 80 g / m2 thick writable kraft paper tape, the effect will be better.

 

3. Adjust the paper feeding system of offset press. Due to the thick writing kraft paper tape, it is necessary to adjust the suction volume of the suction nozzle. At the same time, the paper thickness is also easy to cause shutdown accidents, so before starting printing, the electrical devices such as double sheet control, skew control and pre punching control must be adjusted properly to prevent multiple sheets of writing kraft paper tape from damaging the machine. In addition, the paper suction nozzle and paper feeding nozzle should use rubber band with larger diameter and thickness.

 

4. The center distance between the printing plate cylinder and the rubber drum is kept unchanged when the printing kraft paper tape is printed, and only the center distance between the imprint cylinder and the rubber drum is adjusted. When printing 250 g / m2 ～ 450 g / m2 writable kraft paper tape, the center distance can be increased by 0.2 mm ～ 0.4 mm. The surface of the writable kraft paper tape is rough and poor in smoothness, and the paper is far less compact than that of the coated paper and offset paper. Therefore, the printing pressure should be increased correspondingly when printing the writable kraft paper tape. For example, for printing 400g / m2 writable kraft paper tape, the gap between the plate cylinder and the rubber drum is 3.95mm, the clearance between the rubber roller and the imprint drum is adjusted to 3.40mm, the total lining of the plate cylinder is 0.65mm-0.75mm, and the total lining of the rubber drum is 3.15mm-3.35mm. If the paper changes from thick to thin during printing, the reduced thickness of the liner should be removed from the plate liner and added to the liner of the rubber drum; if the paper changes from thin to thick, the increased thickness of the liner should be extracted from the rubber drum and added to the liner of the plate cylinder.

 

The surface of the writing kraft paper tape is loose and rough, and the paper is easy to shed wool and powder. Therefore, the rubber drum and plate cylinder should be scrubbed frequently during printing, so as to avoid the paper wool and paper powder adhering to the rubber drum and plate cylinder, which will affect the ink transfer, resulting in plate dropping and pen missing. If the writing kraft paper tape has serious shedding and de dusting, in case of monochrome printing, if it is in summer, a layer of water can be overprinted before printing, which can reduce the paper shedding and powdering, and make the paper smoother. In fact, there is not much difference in the manufacturing method between the writable kraft paper tape and ordinary paper. Why is writing kraft paper tape stronger than ordinary paper? This is mainly because the wood fiber used in the production of writing kraft paper tape is relatively long, and when cooking wood, it is treated with caustic soda and alkali sulfide chemicals, so that their chemical effect is relatively mild, and the damage to the original strength of wood fiber is relatively small. Therefore, the paper made from this kind of pulp is closely dependent on the fiber, so it can be used to make paper with this kind of pulp Writing kraft paper tape is very strong.