Adhesive bonding and miscellaneous chemical manufacture – Methods – Surface bonding and/or assembly therefor
Patent
1997-12-12
2000-08-22
Gallagher, John J.
Adhesive bonding and miscellaneous chemical manufacture
Methods
Surface bonding and/or assembly therefor
156279, 1563074, 427204, 427205, 428148, 428150, B32B 3100
Patent
active
061066540
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for the manufacturing of a decorative thermosetting laminate with an abrasion and scratch resistant surface layer.
2. Description of the Related Art
Decorative thermosetting laminates are well known and used for instance as surface material for walls, cupboard doors, desktops, tabletops, for other furniture and as a flooring material.
Such laminates are often made of two to seven Kraft paper sheets impregnated with phenol-formaldehyde resin, a monochromatic or patterned decor paper sheet impregnated with melamine-formaldehyde resin and a fine so called overlay sheet of .alpha.-cellulose impregnated with melamine-formaldehyde resin.
The overlay sheet is intended to protect the decor paper sheet from abrasion. In certain cases the overlay sheet is omitted.
There are also laminates consisting of a base layer of particle board or fibre board provided with such a decor paper sheet and possible an overlay sheet. These sheets can be laminated towards the base layer under heat and pressure. If only a decor paper sheet is used then this can be glued towards the base layer.
The described laminates do have many good properties, it has however turned out that there is a great need of improving the abrasion resistance and the surface scratch resistance of laminates exposed to an extreme abrasion. This is especially the case for flooring laminates, but to a certain extent also for desktop and tabletop laminates.
According to the U.S. Pat. No. 4,940,503 the abrasion resistance of such laminates has successfully been improved. Then a paper web is impregnated with melamine-formaldehyde resin. At least one side of the web is coated with small dry and hard particles with an average particle size of about 1-80 .mu.m, evenly distributed over the wet resin surface on the web whereafter the resin is dried. The particle coated web, so called prepreg is thereafter possibly cut into sheets. At least one such sheet or web is placed as a surface layer on a base layer and bonded thereto. The hereby produced laminate will have a good abrasion resistance.
The hard particles used according to the prior art normally have an average particle size of around 50 .mu.m, which is an advantage from an abrasion point of view. It has, however turned out that the scratch resistance of laminates produced in the known way is not always satisfactory. Furthermore the press plates used during the laminating stage are scratched by the relatively big particles in the surface of the laminate. The press plates are very expensive and manufactured of a high quality steel. Intermediate layers of disposable aluminium foil are often used to protect these press plates which will affect the production cost.
There is a need to be able to produce an abrasion and scratch resistant decorative laminate and to avoid the above mentioned problems.
SUMMARY OF THE INVENTION
It has according to the present invention been possible to achieve a process for the manufacturing of a decorative thermosetting laminate with an abrasion and scratch resistant surface layer, which laminate comprises paper sheets impregnated with thermosetting resin. The process is characterised in that a first continuous paper web is impregnated with melamine-formaldehyde resin, that one side of the first web is coated with about 2-20 g/m.sup.2, preferably about 6-12 g/m.sup.2 of hard particles with an average particle size of about 30-90 .mu.m, preferably around 40-70 .mu.m. The particles are evenly distributed over the whole wet resin surface of the first paper web, after which the resin is dried. The other side of the web, or a second paper web is coated with a melamine-formaldehyde resin, where the resin contains hard particles with an average particle size of about 1-15 .mu.m, preferably about 1-9 .mu.m and in such an amount that the web will have a coating of about 1-15 g/m.sup.2, preferably about 2-10 g/m.sup.2 of these hard particles, whereafter the resin is dried. The particle-coated impregnated
REFERENCES:
patent: 2275989 (1942-03-01), Perry
patent: 3190786 (1965-06-01), Magill et al.
patent: 3661673 (1972-05-01), Merriam
patent: 4940503 (1990-07-01), Lindgren et al.
patent: 5362557 (1994-11-01), Albrinck et al.
patent: 5456949 (1995-10-01), Albrinck et al.
Lindgren Kent
Nilsson Nils-Joel
Velin Per-Erik
Gallagher John J.
Perstorp AB
LandOfFree
Process for the manufacturing of a decorative thermo-setting pla does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the manufacturing of a decorative thermo-setting pla, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the manufacturing of a decorative thermo-setting pla will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-576274