What is the composition and performance of the thermal coating of BOPP thermal synthetic paper?

The thermal coating of BOPP thermal synthetic paper is a key part of its thermal reaction, and its composition and properties have an important impact on the printing effect and paper durability. The following is a detailed analysis of the composition and properties of thermal coatings on BOPP thermal synthetic paper:

Heat-sensitive coating components

The thermal coating of BOPP thermal synthetic paper usually contains a variety of chemicals, which are mixed in a certain proportion to achieve a specific thermal reaction effect. Although formulations may vary from manufacturer to manufacturer, the basic ingredients of thermal coatings usually include the following:

1.Colorless dyes (leuco dyes) : This is one of the most critical ingredients in thermal coatings. At room temperature, these dyes appear colorless, but when stimulated by heat, they rapidly undergo chemical changes, ready to react with the color developer. Commonly used colorless dyes include fluorane compounds.

2.Color developer: Color developer is another key component in the thermal coating that reacts with colorless dyes. When the colorless dye is stimulated by heat, the color developer reacts with it to produce colored compounds, thus forming visible images or words on the paper. Commonly used color developing agents include bisphenol A, p-hydroxybenzoate and so on.

3.Sensitizer: The role of the sensitizer in the heat-sensitive coating is to enhance the sensitivity of the colorless dye to heat, making the reaction more likely to occur. Commonly used sensitizers include benzene sulfonamide compounds. The amount of sensitizer added is usually small, but it plays an important role in improving the speed and clarity of the thermal reaction.

4.Filler: The filler mainly plays a filling and strengthening role in the thermal sensitive coating. Commonly used fillers include calcium carbonate particles. The addition of fillers can improve the opacity of the paper, improve the contrast between the image and the background color, and make the printing effect more clear.

5.Adhesive: Adhesive acts as a bond in the heat-sensitive coating, allowing the coating to adhere firmly to the BOPP substrate. Common adhesives include polyvinyl acetate, etc. The choice and amount of adhesive has an important impact on the stability and printing effect of the coating.

6.Stabilizers: Stabilizers are used to improve the stability of heat-sensitive coatings and prevent unnecessary chemical reactions during storage and use. Commonly used stabilizers include dibenzoyl terephthalate.

7.Lubricants: Lubricants are usually waxy materials used to prevent the print head from sticking to the heat-sensitive coating during the printing process. The addition of lubricant can extend the life of the print head and improve the printing efficiency.

Thermal sensitive coating properties

The thermal coating properties of BOPP thermal synthetic paper directly affect its printing effect and durability. Here are some of the key performance indicators:

1.Thermal reaction speed: Thermal reaction speed refers to the speed at which colorless dyes undergo chemical changes after being stimulated by heat. The faster reaction speed can shorten the printing time and improve the printing efficiency.

2.Print clarity: Print clarity refers to the clarity of the image or text formed by the heat-sensitive coating during the printing process. This depends on the properties of colorless dyes, color developers and other ingredients, as well as the uniformity of the coating.

3.Stability: Stability refers to the ability of thermal coatings to maintain their performance during storage and use. This includes the ability to resist factors such as oxidation, photodegradation and humidity changes.

4.Durability: Durability refers to the durability of the image or text formed by the heat-sensitive coating after printing. This includes the ability to resist factors such as friction, water immersion and chemical attack.

5.Environmental protection: With the improvement of environmental awareness, the environmental protection of thermal sensitive coatings is also getting more and more attention. Environmentally friendly thermal coatings should minimize the use of harmful chemicals and reduce the potential harm to the environment and human body.

In summary, the thermal coating components of BOPP thermal synthetic paper are complex and diverse, and the interaction between the components jointly determines the performance of the coating. In practical applications, the appropriate thermal coating formulation and production process should be selected according to the specific needs to obtain the best printing results and durability.