Film composite
AssigneeCasco Nobel AB
InventorFrancisco Munoz Madrid
Life of this patent
Estimating the term…
Abstract
A film suitable for continuous application to particle boards in the making of laminated particle board is disclosed, which film is stem penetrable and impregnated with semi-cured impregnating resins and provided with a partially cured layer of glue on one side and a fully cured lacquer layer on the other side, which film is permeable to gases generated during production of laminated particle board. A process for producing such a film is also disclosed and also a method for producing a laminated particle board by means of a continuous direct lamination process.
Claims12
A steam penetrable fill which comprises a base paper with a weight of from 30 to 150 g/m.sup.2 impregnated with resins which are semi-cured to a curing degree above 95% and are permeable to gases formed within particle board during the production of laminated particle board, which fill on one side is provided with a partially cured layer of glue and on the other side, a fully cured lacquer layer which is permeable to gases generated during the production of laminated particle board and which film has a water vapor transmission according to ASTM E-96 of above 11 g.h.sup.-1.m.sup.-2 and a water vapor permeance of at least 0.9 kg.Pa.sup.-1.s.sup.-1.m.sup.-2, said film possessing the property of being able to be applied to particle boards in a direct continuous process.
A method for producing a steam permeable film which comprises the steps:
- (a) impregnating of a cellulose web with impregnating resins which are permeable to the gases formed within the agglomerate,
- (b) passing the resin-impregnated cellulose web through an oven for heating and semi-curing,
- (c) passing the impregnated, semi-cured cellulose web to a glue bath,
- (d) passing the impregnated, semi-cured cellulose web provided with a glue layer through an oven for partially curing,
- (e) passing the cellulose web to a lacquer bath where the web obtains a lacquer top coat and then
- (f) passing the web through an oven for curing the lacquer, wherein step e) if desired can be carried out before steps c) and d) whereby a stem penetrable cellulose film provided with top lacquer coat which is fully cured, impregnated with a mixture of semi-cured impregnating resins and a bottom layer of partially cured glue is obtained, said film possessing the property of being able to be applied to particle boards by means of continuous application.
A method for producing a laminated particle board by means of a continuous direct lamination process, wherein on a moving bed of glued wood chips is applied on one or both sides a steam penetrable film comprising a cellulose web impregnated with impregnating resins which are combinations of urea-formaldehyde resins and acrylic emulsions, semi-cured to a curing degree above 95% which web on the surface which contacts the bed of wood chips is provided with a partially cured formaldehyde based glue and which web on the other side is provided with a fully cured heat-resistant lacquer containing polyester or acrylic resin as a binder wherein the bed of glued wood chips and the films are led to and pressed in continuous presses for continuous direct production of a laminate.
Dependencies are inferred from the claim text.