White lined chipboard (WLC) is a type of board that is commonly used for similar purposes as folding boxboard (FBB). It has a typical basis weight of 200-450 g/m2 and is known for its versatility and strength. While the structure of WLC is very similar to FBB, different types of materials are used in its production.

The top ply of WLC is usually made from bleached chemical pulp, although deinked office waste or white ledger may also be used. The purpose of the top ply is to provide a smooth and bright surface for printing and graphics. Between the top and middle plies, there is often an undertop ply which helps to minimize the use of expensive top ply pulp. Deinked pulp, white ledger, or mechanical pulp are commonly used for the undertop ply.

The middle ply of WLC is made from recycled fiber with low brightness. It can be a mixture of old corrugated containers, old newsprint, and mixed waste, depending on the availability of pulp types in the area. This variety of recycled fiber types makes WLC unsuitable for certain food packaging applications, such as chocolate packaging. However, when combined with a protective plastic bag, WLC can be used for packaging groceries like cereals.

The back ply of WLC is typically made from deinked pulp or bleached chemical pulp. This layer provides stability and strength to the board. Overall, the composition of WLC varies between mills based on the availability of different pulp types.

Similar to FBB, WLC is available in rolls or sheets. It is important for WLC to have the same board properties as folding boxboard, such as stiffness, smoothness, and printability. The board machines used for producing WLC and FBB are also very similar, with the main difference being in the stock preparation area.

In conclusion, white lined chipboard is a versatile board used for a variety of purposes, similar to folding boxboard. While it cannot be used for certain food packaging applications, it is still suitable for packaging groceries when combined with a protective plastic bag. The production process and board properties of WLC are similar to FBB, making it a reliable choice for packaging and other applications.