Note: Descriptions are shown in the official language in which they were submitted.
10~33346
BACKGROUND OF THE INVENTION
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Decorative laminates have a wide range of applications
and are generally easier to work with, more versatile
and more economical than hardwood, plywood and high
pressure laminates. They are hardsome, durable,
machineable and inexpensive substitutes and can be
used for furniture, kitchen cabinets, store fixtures,
case goods, displays, desk tops and the like. '
Two types of decorative laminates are available ;
from Champion International Corporation under the
trade marks Decolam/hpt and Vinylcote. These laminates
are made of a wood or board substrate to which a
decorative overlay which is preprinted with wood grain
or solid colors is-laminated. The resulting laminate
may or may not have a smooth, clear, tough protective
layer of an ultraviolet cured polymeric resin.
Hemming et al, U.S. Patent 2,601,284, teach a
laminate in which an adhesive is applied to a
substrate (board), an aluminium sheet or foil is
placed over the adhesive, a second layer of adhesive
. ~ o
s - applied to the sheet or foil and then a wood veneer
is placed on the second layer of adhesive. It has
; 25 now been found that the general type of structure
disclosed by Hemming et al can be advantageously
modified by eliminating the aluminium sheet or foil
and second glue ~ayer and, instead, employing an
adhesive which has an aluminum powder dispersed therein.
Accordingly, it is the object of this invention to
~ provide a new and highly advantageous decorative and
- heat resistant laminate without resorting to -the use
of the metal foil or sheet therein. This and other
objects of the invention will become apparent ~o
those skilled in the art from the following detailed ,~ ?
,., ~
description.
~83346
.
This invention relates to the woodworking field,
and particularly to the building material industry, the
furniture industry, and the fancy container industry.
Specifically, the invention relates to a low pressure
decorative and heat resistant laminate material where
a wood base or other substrate member is directly
adhered to a decorative plastic film by an adhesive
having aluminum powder dispersed therein.
The substrate employed in the decorative laminate
of the instant invention can be chosen from a wide
variety of materials such as particle board, hard board,
fibre board, lauan plywood, and the like. The substrate
serves as a base to which a thin, decorative plastic
film is laminated to give the composite structure and
the desired appearance. The plastic film is not restricted
to any particular plastic but it is presently preferred to
use a polyvinyl chloride film which has been preprinted in,
for example, simulated wood grain or solid colours. The
plastic film generally has a thickness of about 1 to 10 mils,
-20 preferably 2 to 6 mils, and the substrate is generally at
least about five times thicker than the plastic film.
The thin plastic film is adhered to one or more
surfaces of the substrate through the use of an appropriate
adhesive or glue. Any of the known and conventional
adhesives such as~phenol-formaldehyde, urea-formaldehyde,
., ~,
melamine-formaldehyde, furfural resins, polyvinyl resins,
urethane resins, mixtures of phenol-formaldehyde and
butadiene acrylonitrile synthetic rubber, synthetic
rubber derivatives mixed with phenol-formaldehyde resins,
poly-~inyl butyral mixed with phenol-formaldehyde, and che
,
~0833~6
like can be employed in this invention. Aluminum
powder in the form of spherical, flake or other desired
shape particles having an average particle size of about
5 to 50 microns is dispersed in the adhesive in the con~
ventional manner such as, for example, by use of a ball
mill or colloid mill. The aluminum powder is usually
about 10 to 50 weight percent, preferably about 20 to
35 weight percent of the resulting aluminum powder con- i
taining adhesive. The use of a~uminum powder as herein
taught contributes to a great extent to the heat resistant
properties of the laminate.
In forming the decorative laminates of the instant
invention, the selected substrate is sanded as required,
cleaned and then the aluminum powder containing adhesive
is coated on the substrate surface and optionally dried. ,r
If dried, the adhesive is subsequentl~ reactivated by
moderate heating. A preprinted polyvinyl chloride g
decorative film is placed on the adhesive coated surface
and lamination is effected under moderate heat and pressure.
Thus, it has been found that pressures of about 8 to 40 kg/lcm,
s~ preferably about 12 to 25 kg~lcm, and temperatures of
- about 160 to 200C., preferably about 90 to 160 degrees `
centigrade, are suitable. `
Although not essential, it is preferred to provide
a tough, heat and water resistant protective coating on
the thin plastic film. This is preferably accomplished
by spreading a suitable liquid polymeric resin on the
plastic film surface and then converting the thermoplastic
resin to a strong, infusable, clear, colourless solid. The
choice of the polymeric resin is not restricted and can be,
- 3 -
1~833~
for example, a polyester resin, an allyl resin, an
acrylic resin, poly-vinyl chloride-diallylsuccinate,
styrene-divinylbenzene, isobutyl urea-formaldehyde,
isobutyl melamine formaldehyde, and the li~e~ For ease
in handling, it is preferred that the polymeric re-;in
selected be a liquid material which is adapted to
quickly cure upon the application of ultraviolet light.
As an example of the present invention, a 3/8th
inch particle board substrate was lightly sanded and
cleaned and then coated with a urethane adhesive in
which 25% was dispersed aluminum powder having an
average particle size of 25 microns. The adhesive ~`
coated substrate was then set aside and allowed to dry.
Thereafter, the adhesive coated substrate was subjected
to a low heat of 130C. and a 2 mil thick preprinted
polyvinyl chloride film was laminated to the adhesive
coated surface under roller pressure (about 12 kg/lcm).
Thereafter a li~uid acrylic resin was applied to the
exposed polyvinyl chloride surface in a clean, dust-
S20 free atmosphere and i~mediately cured with ultravioletlight energy.
The use of the aluminum powder filled adhesive in
the instant invention is advantageous because the heat
dissipation characteristics of the aluminum material
are imparted to the laminate. The use of the aluminum
powder dispersed in the adhesive is more advantageous
than the use of an aluminum sheet or foil as used here-
tofore because the use of the aluminum powder allows
j.for a cost reduction since the adhesive and aluminum
can be applied in t~e same application.
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1[)83346
Various changes and modification can be made in
the process and products of this invention without
departing from the spi.rit and scope thereof. The
various embodiments set forth herein were for the
purpose of further illustrating the invention but were
not intended to limit it.
