As a modern packaging material, paper is mainly used to make packaging products such as cartons, cartons, paper bags, paper containers, etc. Among them, corrugated cardboard and its cartons occupy the dominant position of paper packaging materials and products; composite paper composed of a variety of materials And cardboard and special processed paper have been widely used, and will partially replace the application of plastic packaging materials in food packaging to solve the environmental protection problems caused by plastic packaging.

1. Printing performance

Both paper and cardboard have a good ability to absorb and bond ink, print well, and are often used as a printing surface on packaging. The printing ability of paper and cardboard mainly depends on the surface smoothness, elasticity, adhesion, etc. of the material.

2. Health and safety performance

In the production of paper raw materials, especially chemical pulping, some chemical substances (such as lye and salts remaining in the Kraft pulping process) are usually left, so it is necessary to correctly select various paper according to the packaging contents and cardboard.

3. Mechanical properties

Paper and cardboard have certain strength, stiffness and mechanical adaptability, and its strength is mainly determined by the material, quality, thickness, processing technology, surface condition and certain temperature and humidity conditions of the paper; in addition, paper also has certain folding It is suitable for making shaped packaging containers or for wrapping.

Ambient temperature and humidity have a great influence on the strength of paper and cardboard. Changes in air temperature and humidity will cause changes in the balance of moisture in paper and cardboard, and ultimately change their mechanical properties to varying degrees. The mechanical properties of paper change with relative humidity. Because paper fibers have greater water absorption, when the humidity increases, the tensile strength and tear strength of the paper will decrease, which will affect the usability of paper and cardboard. A relative temperature and humidity condition must be maintained when measuring the mechanical properties of paper and paperboard.

4. Barrier performance

Paper and cardboard are porous fibrous materials, which have a certain degree of permeability to moisture, gas, light, grease, etc., and their barrier properties are greatly affected by temperature and humidity. Single paper packaging materials generally cannot be used to package foods with high moisture and oil content and high barrier properties, but can meet the barrier properties requirements through appropriate surface processing.

5. Processing performance

Paper and cardboard have good processing properties, can be folded, and can be sealed in a variety of ways. Good processing performance makes it possible to design various functional structures (such as windows, handles, partitions and design display stands, etc.). In addition, through appropriate surface treatment, paper and cardboard can be provided with necessary moisture resistance, insect resistance, barrier properties, heat sealing properties, strength and physical properties, etc., and their application scope can be expanded.