How is the color of BOPP colored synthetic paper attached?

The color adhesion of BOPP (biaxially oriented polypropylene) colored synthetic paper mainly depends on the thermal sensitive coating and its coating process. The following are the main steps and principles of color attachment:

1、 Composition of thermal sensitive coating

Thermal sensitive coating is formed by coating chemical substances such as latent dyes and color developing agents on the surface of BOPP film through a special process. Hidden dyes are colorless at room temperature and do not spontaneously develop color. And the color developer plays a catalytic role in the thermosensitive reaction, participating in the color reaction together with the latent dye.

2、 Color adhesion principle

Thermal reaction: When BOPP color thermal synthetic paper encounters a heated print head or other heat source, the temperature in the local area of the coating rapidly increases. High temperature causes the melting and chemical reaction of latent dyes and color developing agents. Under the catalytic action of the chromogenic agent, the structure of the latent dye changes, resulting in the appearance of color. As the temperature decreases, the color reaction is completed and the color is fixed on the paper, forming the desired image or text.

Coating uniformity: The coating uniformity of thermal sensitive coatings directly affects the color uniformity and restoration degree. The coating process requires strict control of the composition, concentration, and coating amount of the coating liquid to ensure the performance of the final product. If the coating is not uniform, it may lead to color spots and unevenness.

3、 Color attachment process

Preparation of film: BOPP film produced through raw material preparation, mixing, plasticization, extrusion, casting, cooling, stretching, and surface treatment serves as the basis for coating.

Thermal sensitive coating: Apply a thermal sensitive coating uniformly on the surface of a thin film containing chemical substances such as latent dyes and color developers.

Drying and curing: After the coating is applied, it needs to be dried and cured. Appropriate drying and curing conditions can ensure stable coating performance and accurate color reproduction.

Follow up processing: As needed, primer and protective layer coating can also be applied to enhance the performance and protect the color of the paper.

4、 Precautions

Ink adaptability: During the coating process, it is necessary to choose specialized ink or coating materials suitable for BOPP film to ensure that the color can evenly adhere to the surface of the paper and form a clear and full printing effect.

Quality control: Throughout the entire production process, it is necessary to strengthen quality control and testing to ensure that every step meets standard requirements, thereby ensuring the color adhesion effect and color reproduction of the final product.

In summary, the color adhesion of BOPP color synthetic paper is achieved by uniformly coating a thermosensitive coating containing hidden dyes and color developing agents on the surface of BOPP film, and then undergoing drying and curing treatment steps. During this process, it is necessary to strictly control the parameters and quality requirements of each step to ensure that the final product achieves the expected color adhesion effect and color reproduction.