There are a lot of papers used specifically in bookbinding. There is repari tissue, a strong pure Gampi paper. A pure Kozo used to lamingate thin papers and fabricks to make a sutiable covering material, expecially silk, as well as strengthen edges and torn pages. Sometimes used to mend inner and outer hinges hinges. It can be dyed to a suitable colour.
There are endpapers from plain colours of different weights to richly patterned Japanese, Himalayan and other handmade patterned papers.
For spine dressing there is kraft and cartridge paper plus the soft and thicker printmaking paper.
Blotting paper is available and is used at various stages of drying and flattening lamingated papers and made endpapers.
The acid free 118gsm Eggshell papers in A4 short grain are suitable for A5 text blocks Also used for test pages are larger sheets of a cotton paper, the 118gsm Eggshell plus the 110gsm cartridge paper and the natural looking kraft paper. These larger sizes allow for folding and deckle cutting to the desired size.
Acid free Bookbinders board is available in 1mm, 1.8mm and 2.4mm