The paper coating process is complex and requires the use of a variety of equipment and instruments to achieve the desired characteristics of the final product. Understanding the equipment, instruments and experimental methods used in these processes is essential to ensure product quality and consistency. The following is an overview of the key equipment, instruments and experimental methods involved in the paper coating process.

Overview of equipment, instruments and experimental methods in paper coating process

Equipment and instrumnts

Experimental method:
1, beating

Beating is the process of tearing the pulp board into small pieces of specific size and soaking it in water for a certain period of time to dredge and stir. First, the pulp raw material board is torn into small pieces of the specified size and then soaked in water for a period of time to soften the fiber. The fiber is then thoroughly dispersed and the desired slurry texture and properties are achieved by stirring and stirring with specific equipment, such as a Vally beater or other slurry handling device.

Overview of equipment, instruments and experimental methods in paper coating process

2. Dredge

Dredging refers to the chemical or physical treatment of pre-treated pulp boards soaked in specific equipment to open the fiber bundles and dissociate the fibers. This process can use equipment such as fiber standard dissociators, through the flow of water or mechanical rotation, so that the fiber is cut, stretched and torn, so that it is separated into smaller fibers, improving the quality and uniformity of the pulp.

3. Mix pulp

Pulp mixing is to mix different kinds of pulp raw materials according to the predetermined proportion and formula to prepare the pulp that meets the requirements. The key to this step is to ensure that the various pulp raw materials are correctly mixed in the designed proportions and are stirred evenly to obtain the desired paper characteristics and quality.

4. Copy the film

Sheet making is the process of making paper with the prepared pulp in the paper machine according to the predetermined plan. In this process, chemical additives are added to the pulp according to the design plan, and then the pulp is copied into sheets of paper by rollers or other devices on the paper machine.

5. Surface sizing

Surface sizing is the process of applying glue solution to the surface of the paper under constant temperature and humidity after the base paper has been treated by a specific process. This process involves gelatinizing substances such as cationic starch and mixing them proportionally with other sizing agents, then pressing and coating the paper by hand after it is treated with constant temperature and humidity.

Overview of equipment, instruments and experimental methods in paper coating process

6, paint preparation

Coating preparation involves the dispersion and mixing of materials such as pigments and binders. First, the pigment is weighed and dispersed by adding a dispersant, then a binder is added, including an auxiliary binder and the main binder latex, and finally other additives such as hydration resistant agents, lubricants and substances needed to regulate pH are added to maintain the rotational speed so that the paint is evenly mixed.

7, paint viscosity test

The viscosity of the coating was measured by a rotary viscometer. By setting the rotation speed, observe and record the viscosity of the paint under specific conditions to ensure that it meets the production requirements.

8. Paper coating experiment

The base paper is placed on the coating machine according to the requirements, and the amount and uniformity of the coating are monitored through the machine to meet the specific requirements of the product.

Overview of equipment, instruments and experimental methods in paper coating process

9. Paper calender experiment

Under constant temperature and humidity conditions, the coated paper is calendered to make the surface of the paper more flat and smooth, and improve the overall quality of the product.

10, paper performance test

The coated paper is tested for a variety of properties, including gloss, smoothness, printing surface strength, thickness, opacity, whiteness, tensile strength and cohesion.

11. Determination of coating coverage

The coating coverage rate of coated paper was quantitatively analyzed by burning method. The coated paper is treated with specific experimental steps and equipment, and equipment such as scanners are used to observe and quantify the coverage of the coating.