First, brush coater
The brush coater is the oldest coating equipment originally used in the 1950s to produce coated wall paper using china clay coatings. There are three different types of brush coating heads: a round brush coating head, a blanket roll coating head, and a blanket coating head. Figure 1 shows an early application of a brush coating head.
Second, air knife coating machine
The advent of air knife coaters in the 1930s marked the birth of the modern paper coating industry. The air knife coater overcomes the aforementioned shortcomings of the brush coater and is rapidly being promoted, resulting in a sharp increase in the production of coated paper.
Third, the blade coating machine
The first patent for a knife coater appeared in the 1950s. Since then, the blade coater technology has been rapidly developed. According to the feeding equipment, the type of scraper and the mounting position of the scraper, the scraper coating head is also divided into many types, such as hard blade scraper coating machine, drag knife scraper coating machine, soft blade scraper coating machine, fountain type. A knife coater, a short-residence knife coater, a billet coater, a scraper coater, and the like.
Fourth, roll coater
Roll coating is applied to the coated surface by a coating roll, and the inner coating is mainly such a coating machine. The amount of coating can be adjusted by the pressure between the metering rolls, the pressure is increased, the throughput of the coating is reduced, and the amount of coating is reduced. Type of roll coater:
1. Press roll coating head
2, reverse roll coating head
3, transfer roller coating head
4, gravure roll coating head
Five, spray coating
Spray coating technology is a non-contact coating method that uses a controlled high pressure spray technology to coat paper or paperboard on one or both sides (sizing).
Sixth, curtain coating
The multi-layer curtain coater can impart a three-layer structure (bottom layer, absorbing layer and top layer) to the surface of the inkjet printing paper with only one coating operation, and can obtain a uniform coating on the uneven paper surface.
Seven, slit coating
The slit coating head includes a coating liquid storage tank; a pump for pumping the coating liquid in the coating liquid storage tank to the nozzle through the supply line; and a control portion for controlling the operation of the pump and the nozzle The pressure detecting portion is configured to detect the line pressure, and the nozzle removes the coating liquid when the pressure reaches a predetermined pressure condition.