Specific weight of cardboard and its characteristics. Weight of cardboard per 1 m².

Cardboard is a layered material made from cellulose raw material. The outer layers are made from higher-quality materials, while the middle layer is often made from paper industry waste and recycled paper. Therefore, the price of cardboard varies depending on the quality of the raw material used.

The quality characteristics of cardboard include:

• Thickness of the cardboard sheet
• Volumetric weight of the pressed material
• Stiffness indicator (longitudinal and transverse — depends on the fiber direction)
• Susceptibility to coloring pigments
• Density of cardboard

Volumetric weight has a significant effect on the ability to form bends and corners. Cardboard stiffness means its strength. Thus, cardboard made from cellulose pulp or wood will be stronger, but this can also indicate brittleness. The ratio of raw materials must be selected very carefully in order to preserve all the necessary functions of cardboard and products made from it.

For a colored product, it is important to make sure that the material can be dyed. If the cardboard has a whitish surface, the color will be rich and bright.

International classification of cardboard

Manufacturers use an international classification when producing cardboard; it is shown in the table.

Features of packaging cardboard.

Packaging cardboard is widely used in the production of various boxes and containers. It is most often used in the food industry, pharmaceuticals, household chemicals, cosmetology and perfumery. Although manufacturers increasingly use polymer packaging, packaging cardboard retains its position thanks to its stiffness, high barrier properties and strength.

Packaging cardboard is conventionally divided into recycled and primary cardboard. Both types include several layers. Thanks to this structure, cardboard becomes stiff and thick. The main materials used for production are wood, cellulose pulp (bleached and unbleached) and recycled paper. If recycled raw material is used in the production of cardboard, its price and hardness are significantly reduced.

The resistance of cardboard to moisture and grease is no less important. If it is necessary to improve barrier properties, cardboard can be coated with polymer emulsions. Such coating is especially important in food packaging.

Packaging cardboard includes two types of products: corrugated cardboard and cardboard boxes. A distinctive feature of corrugated cardboard is its multilayer structure with corrugated layers.

Cardboard used in the production of corrugated cardboard is divided into several types, and their density also differs significantly.

The weight of 1 m³ of cardboard in pressed form is 700 kg/m³. If necessary, corrugated layers can reach a mass of 450 g/m², while flat layers have a mass of no more than 225 g/m².

Advantages of using asbestos cardboard.

The basis for the production of asbestos cardboard is chrysotile asbestos fiber with special binding components. Asbestos cardboard is most often used to insulate containers and equipment that operate at high temperatures. It does not support combustion and tolerates heating well, but cutting, wear and dust formation require strict safety rules because asbestos fibers are hazardous.

Asbestos cardboard is most often produced in sheets of 800 × 1000 mm and with a thickness from 2 to 10 mm. The main weight parameters of asbestos cardboard are usually specified per 1 m².

Characteristics and main indicators of gasket cardboard.

Gasket cardboard is used as an interlayer in construction processes and technical joints. It is often used for transporting fragile goods and as a frame base for accessories (bags, wallets, purses and clutches).

It is usually produced in sheets measuring 750 × 1150 mm. The weight of gasket cardboard is about 1.2 kg.