ITEMS MADE OUT OF PAPERBOARD OF LOW DENSITY Russian patent published in 2004 - IPC

FIELD: woodpulp and paper industry; production of a paper and a low density board.

SUBSTANCE: the invention is intended for use in a wood-pulp and paper industry in by production of a paper and a paperboard of low density used for manufacture of insulating vessels, for example, cups. The paperboard material contains the paperboard linen containing wooden fibers and the dispersed among filaments microspheres having an apparent density approximately from 0.38 up to 0.64 g / cm³ and a thickness of plate from 609 up to 889 microns at strength of the internal binding at least near 168 х 10^-3 kJ/m², and mainly of at least about 210 х 10^-3 kJ/m². For such items as cups the indicated material has on one or both sides a barrier coating, in capacity of which a low density polyethylene is mainly used. The cups barrier coating is mainly intended to limit infiltration of a liquid into the paperboard linen. The surface of the paperboard of a low density has the surface finish by Sheffeld's of about 300 SU or more, as compared with the surface finish from 160 up to 200 SU for the routine raw material at manufacturing of such cups, that earlier was regarded as necessary for provision of good quality of printing. The low density paperboard provides a high quality of printing by flexographic printing press, in spite of a rather low surface finish, that appears as an unexpected advantage of the paperboard together with its insulation and strength properties.

EFFECT: the low density paperboard provides a high quality of printing by flexographic printing press, good insulation and strength properties.

6 cl, 5 dwg, 3 tbl, 3 ex