Visible laid pattern effect in a picture book illustration by Randolph Caldecott. Published 1887, digitally restored.

Laid paper is a type of paper having a ribbed texture imparted by the manufacturing process. In the 19th century its use diminished as it was largely supplanted by wove paper. Laid paper is still commonly used by artists as a support for charcoal drawings.

In pre-mechanical papermaking (from the 12th century into the 1800s), the laid pattern was produced by the wire sieve in the rectangular mold used to produce single sheets of paper. A worker would dip the mold into a vat containing diluted linen pulp, then lift it out, tilt it to spread the pulp evenly over the sieve, and, as the water drained out between the wires, shake the mold to lock the fibers together. In the process, the pattern of the wires in the sieve was imparted to the sheet of paper.^[1]

Modern papermaking techniques use a dandy roll to create the laid pattern effect during the early stages of manufacture, in the same way as applying a paper watermark. While in the wet state, the paper stock (a dilute dispersion of the cellulose fibers in water) is drained on a wire or mesh to de-water the stock. During this process, a dandy roll with a laid mesh pattern is pressed into the wet stock which displaces the cellulose fiber. This pattern has to be applied at a particular fiber consistency, otherwise the pattern will be lost as the fiber flows back as the stock moves past the dandy (too wet) or fiber will pick out of the stock (too dry), causing surface disruption. As the fiber is displaced, it creates localized areas of higher and lower density in a laid pattern as well as leaving a laid texture on the papers surface. This texture is therefore seen by both looking through the sheet as well as on its surface. Applying laid pattern as a mechanical emboss would not create the laid pattern effect on the look-through, as this is only achieved by watermarking techniques.

The traditional laid pattern consists of a series of wide-spaced lines (chain lines) running in the machine direction—or, in hand-made paper, parallel to the shorter sides of the sheet—and narrower lines (laid lines) which are at 90 degrees to the chain lines.

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