pulp board (material)
A board material made in single thick sheets from coarsely pulped paper, typically acquired from the trimmings from the cut edges of bookblocks, waste printed or manuscript paper, etc. When it breaks down at broken corners, it will not divide into layers but into very uneven flake-like fragments of paper. Pulp boards were made in a variety of thicknesses, and thinner boards were often laminated together with an adhesive to build up the thickness for larger books. The pulp appears to have been formed into sheets over a woven screen, the impression of which is therefore found on one side of the board. These screens appear to have been made of a textile, often of a very coarse weave, not unlike sacking. Careful binders made sure that the screen-side of the board was placed against the bookblock, so as not to show through a leather cover. Pulp boards are typical of British binding from the last quarter of the sixteenth century through to the third quarter of the seventeenth century, after which they become increasingly rare, except for the cheapest books, on which they may occasionally be found up until the early nineteenth century. They do not appear to have been much used on the continent of Europe. They were made both by professional suppliers of board and, from the appearance of tubs and moulds in inventories of binders' workshops (Strickland Gibson, 1907), sometimes by the binders themselves, who would collect edge trimmings from books they bound and other waste material in a waste bin (often the tub under the laying press) in their workshops for this purpose. As a result, small bits of other types of material, including textile, thread, parchment, quill trimmings, fragments of wood, metal pins, etc., may be found in the boards (Middleton).
papirmasse som i fuktig tilstand formes eller presses etter tilsetning av lim- eller fyllstoffer