Note: Descriptions are shown in the official language in which they were submitted.
1085706
BACKGROUND OF THE INVENTION
The production of fabric-backed wallcoverings has materially
increased in recent years. The increase in volume is attributed to the
ease of application of these wallcoverings to the wall as well as the
ease in removal thereof. Additionally, fabric-backed wallcoverings
have proven popular because they are easily cared for and maintained.
As the popularity of fabric-backed wallcoverings increased,
so did the consumer's demand for more diverse patterns and variety. As
a result, manufacturers have, more recently, attempted to produce
wallcoverings having deeper and clearer color and in a variety of
patterns. These newly introduced designs have also proven successful
and wallcovering manufacturers are now attempting to develop even more
attractive and durable products.
One product which has not proven to be easily produced is a
metallic and flocked wallcovering. This difficulty of production is
apparently due to the fact that conventional laminated wallcoverings do
not have the thermal stability to allow the fusion of a plastisol flock
adhesive thereto, which fusion requires a temperature of about 275C.
Attempts to fabricate such products have resulted in curling, wrinkling
and delamination of the product within seconds after reaching this
fusion temperature. Wallcoverings produced by adhesively bonding
preformed films directly to the fabric backing, on the other hand, are
more expensive because such films cannot be as heavily loaded with
pigment as is required, because of conditions of their manufacture.
Additionally, the adhesive lamination technique does not enable the
film to be locked onto the fabric and delamination can occur.
SUMMARY
I have now discovered that thermally and dimensionally stable
wallcoverings can be produced, which wallcover-
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ings achieve the aesthetics of deep gloss, metallic reflect-
ance and flock. They couple their pleasing, aesthetic decora-
tive effect with ease of application, excellent durability,
scrubability, stain-resistance and ease of removal.
Articles of manufacture related to those disclosed
and claimed herein are set forth in United States Patent No.
2,702,580. The instant wallcoverings, however, are superior
to articles taught therein, as enumerated hereinbelow.
DESCRIPTION OF THE INVENTION
INCLUDING PREFERRED EMBODIMENTS
In one aspect the invention resides in a thermally
and dimensionally stable wallcovering and a process for the pro-
duction thereof. The wallcovering weighs from about 6.0 to
about 11.8 ounces per square yard and comprises, in superimposed
relationship,
(1) a fabric material weighing from about 0.5 to
about 1.4 ounces per square yard,
(2) a calendered coating atop said fabric of a
filled vinyl chloride/vinyl acetate copolymer, the coating
weighing from about 3.5 to about 4.5 ounces per square yard,
(3) a clear, adhesive coating, atop said calendered
coating, of a vinyl chloride/vinvl acetate copolymer, the
adhesive coating weighing from about 0.2 to about 0.4 ounces
per square yard,
(4) a film of polyethylene terephthalate having a
metal surface on one side thereof with a heat-sensitive coating
thereon, and a thermosetting polyester coating on the other
side, with the heat-sensitive coating adjacent said adhesive,
(5) a vinyl adhesive coating on said polyester
coating and
(6) flocking applied to said vinyl adhesive.
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In a further aspect of the invention there is pro-
vided a method for the production of the wallcovering as defined
above which comprises
(a) coating a woven or non-woven cellulosic or
synthetic fabric weighing from about 0.5 to about 1.4 ounces
per square yard with sufficient aqueous, filled vinyl chloride/
vinyl acetate copolymer latex so as to apply thereon, when
dried, a coating weighing from about 3.5 to about 4.5 ounces
per yard,
(b) drying the resultant coated fabric,
(c) calendering the resultant, dried, coated fabric,
(d) coating the resultant calendered, dried, coated
fabric with sufficient vinyl chloride/vinyl acetate copolymer
solution so as to apply thereon, when dry, an adhesive coating
weighing from about 0.2 to about 0.4 ounces per square yard, ~ :
(e) drying said adhesive coating, `
(f) adhering a film of clear polyethylene terephthal- :~
ate which is metalized on one surface thereof and has a heat-
sensitive adhesive coating on said metal and a thin, clear,
thermosetting polyester coating on the other side thereof, to
the dried, adhesive coating, the dried adhesive coating and
the heat-sensitive adhesive being contiguous,
(g) coating the printed design with a vinyl adhesive :~
and
(h) applying flock to said vinyl adhesive coating.
The above six components are all critical in pro-
ducing the novel wallcoverings of the present invention; how-
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26,426 ever, components (1) and (2) form the critical base without
which the remaining components cannot be used. The coated
fabric material is the key to this invention because the coat-
ing actually penetrates the fabric interstices and locks into
the fiber, resulting in the required thermal and dimensional
stability necessary to apply the metalized film thereto
The sub trate material comprises a woven or non-woven
fabric of cotton or other cellulosic material or synthetic
fibers such as polyesters of the above weight alone or in ad-
mixture with one another. Cotton-polyester materials should
contain about 50~ of each component. A suitable polyester is
Dacron woven fabric possessing the weight requirements spec-
ified above usually has a thread count of from about 23-30 per
inch in both the warp and fill direction. Mixtures of cotton
thread and polyester thread can be used, one type of thread
being used in the warp direction and the other in the fill
direction. It is preferred that the warp direction thread
always be pure cotton. The non-woven fabrics useful as
substrates herein are generally composed of very long synthetic
fibers laid down in a random fashion to produce a non-direction-
al mat. The fiber intersections are secured by fusing or by
application of an adhesive.
The material used to coat the fabric backing member
is a heavily filled vinyl chloride/vinyl acetate copolymer.
The vinyl acetate is used at from about 5% to about 15%, by
weight, based on the total copolymer weight. It is applied to
the fabric as an aqueous latex and can be filled with such
materials as TiO2, ZnOz, BaSo", CaCO3, clays, talcs, aluminum
hydrates and the like in amounts xanging from about 50% to
about 350%, by weight, based on the weight o~ the dry vinyl
chloride copolymer. External plasticizers such as phthalates,
epoxidized tall oils and the like may also be incorporated
depending upon the desired flexibility of the finished product.
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26,426 Antifoaming agents, suxfactants, thickeners etc, may also be
included, The heavy mineral loading contributes to the thermal
stability of the final product by reducing the thermoplastic
character of the vinyl chloride copolymer coating. An optional
top coating may be applied to the fabric coated with the filled
vinyl chloride/vinyl acetate copolymer. This top coat is a
second application of the above aqueous copolymer latex and
again contains the filler but in proportions of filler to
polymer of at least 2.5;l, It aids the first coating or "daub"
and provides a more sturdy support for the other subseguently
added wallcovering components. Other minor variations in this
material can be made. The first latex coating is applied so as
to result in the addition of 3.5-4.5 ounces per square yard
when dry while the optional second latex coating is used in
amounts so as to deposit 0.0-3.0, preferably l.8-3.0 ounces
per square yard to the final wallcovering.
To the vinyl chloride/vinyl acetate copolymer layer
or layers on the fabric is next applied a clear, vinyl chloride/
vinyl acetate copolymer adhesive. Suitable copolymers contain
at least abffut 86% vinyl chloride, the remainder being vinyl
acetate. Up to about 2.0% of the vinyl acetate can be replaced
by a copolymerizable dibasic acid such as maleic acid, fumaric
acid etc. It is applied very sparingly as a solvent solution by
gravure printing and is used to increase bonding of the
metalized terephthalate film to the first coating. Evaporation
of the solvent results in the deposit of the clear adhesive filn
The polyethylene terephthalate film ranges in thick-
ness from about 0.5 mil to about 5,0 mils and adds the bulk
of the remaining weight to the wallcovering. It has a metal
film on one of its surfaces, of which aluminum is preferred.
Other metals such as copper etc. can be used. The metal film i~
thin and i8 applied onto the polyethylene terephthalate by
vacuum deposition as is known in the art. The polyethylene
terephthalate film is preferably biaxially oriented as is
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26,426 also known in the art. Atop the metal film there is coated a
heat-sensitive adhesive layer Any adhesive which conforms
to this definition may be used with such materials as 85-88%
vinyl chloride, 11-14~ vinyl acetate, 0.8-1.2% maleic acid
terpolymers and the like being exemplary. On the surface of
the terephthalate film opposite the metalized side is posi-
tioned an optically clear, thermosetting polyester coating
which serves as the flock receptive layer. Examples of ma-
terials useful for the purpose include condensation products
of glycols and dibasic acids having reactive side groups.
The polyethylene terephthalate film, as desc-ribed
above, containing said coatings, is applied to the coated
fabric with the metalized side facing said fabric by heat
and pressure.
A print design is then optionally, but preferably,
applied to the polyester layer utilizing any conventional
gravure printing equipment. The use of vinyl inks is pre-
ferred, however, any other type of ink which enables the de-
sign to be readily printed onto the polyester surface may be
used such as acrylic gravure printing inks and the like.
An adhesive capable of retaining flock is then ap-
plied to the wallcovering. The flocking adhesive may be
gravure printed or plastisol printed onto the surface and may,
in some instances, cover some of the same area upon which
the design is printed. This adhesive enables the flock to
be securely attached to the wallcovering and ensures increased
washability. Suitable adhesives include polyvinylchloride
plastisols, various aqueous acrylics and the like. Of course,
the flock can be applied to any part of the uppermost wall-
covering surface in order to achieve the particular decorative
effect desired. It is preferred, however, that flock be
applied to at least some of the area where the design has
been printed. The adhesive can contain plasticizers,
stabilizers, and can be applied fxom solvent solution. The
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flock fibers are preferably rayonl but other fiber-forming polymers such as
polyacrylonitrile can also be used. Natural fibers are also useful.
The wallcoverings of the instant invention are prepared as follows.
The fabric is first placed under tension and straightened by placing it on a
suitable mechanical web handling and aligning device. The aqueous vinyl
chloride/vinyl acetate copolymer latex is applied, preferably via the coating
- mechanism of the web handling device, in an amount sufficient to deposit the
required weight of solids. The coated fabric is then passed through a suit-
able dryer such as an air circulating oven at about 325C. in order to remove
water from the coating. This procedure coalesces the composition and causes
the formation of a film.
The resultant dry, coated fabric is then removed from the mechanical
device, the edges of the material are trimmed and the second latex coat, if
desired, is applied by using a suitable device such as an air knife. The thus
-~ coated fabric is then passed through another dryer such as an air circulating,
hot air oven at 325F. ~as above) to dry the second coating. While still hot,
i.e., at about 275F., the thus coated web is fed between the crushing rollers
of a calender stack at about 300 pounds per lineal inch pressure in order to
obtain a smooth surface. Chilling of the smoothed material is then required
to set the smooth surface.
The resultant material is next placed on a gravure printing machine
and the vinyl chloride/vinyl acetate copolymer adhesive is applied to the
smoothed, coated surface of the fabric. A tint of 1/2% carbon black is
usually added to the adhesive in order to assure by visual detection that this ;
adhesive remains on the fabric during subsequent treatment. The adhesive is
deposited using any suitable cylinder such as a gravure cylinder having 55 ;~
l.p.i. quadrahelic etch at the required level and dried.
The adhesive coated product is then preheated by passing it around a
heated drum (e.g., at about 320F.) with the back uncoated portion of the
fiber in contact with the drum. At a point about 1/3 around the circumference
of the drum, the coated surface of the article is brought into contact with
the metalized polyethylene terephthalate film, the coated face of the fiber
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5706
being in contact with the heat-sensitive adhesive face of the metalized film.
The two webs continue around the heated drum and are then fed between the
smooth rollers of a laminating nip press. Web temperature is controlled at
about 270F. and the laminate is consolidated into a unitary structure at
about 400 pli pressure on the chilled nip rollers. The metalized material is
then cooled to ambient conditions and printed with the desired design using
conventional gravure printing cyclinders and vinyl inks if desired. The
printed design may form a background of a design different from that of the
flock to be applied, an outline design or the same or an independent design.
The vinyl adhesive is applied to the printed area in the same desired pattern
at a subsequent station and the resultant web is then passed under a hopper
where the flock is deposited. Orientation of the deposited flock is achieved
by means of a beater bar, electrostatic charge etc. to thereby set up the
flock. Excess flock is vacuumed off and the flock adhesive is fused at a
temperature in excess of about 275F. to bond the flock. Embossing of the web
can be effected anytime in the process, but is preferably conducted after the
metalized film is applied and before printing and flocking, by passing it
through a conventional embossing apparatus.
The following examples are set forth for purposes of illustration
only and are not to be construed as limitations on the present invention
except as set forth in the appended claims. All parts and percentages are by
weight unless otherwise specified.
EXAMPLE 1
A cotton sheeting fabric backing member, running about 8.7 yards per
pound per 50 inch width, i.e., 1.2 ounces per square yard, and having a thread
count of 30x30 is coated on one side with an aqueous pigmented vinyl latex,
the member having been placed under tension and straightened by a mechanical
coating and web aligning device. The vinyl latex has the following
composition:
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~085706
A. Coating Grind (70% solids)
Material Wt. Lbs.
1. Water 28.20
2. Tetra sodium pyrophosphate .20
3. TiO2 slurry (67% solids) 15.94
4. Antifoam solution - 50% .13
5. CaC03 67.35
,
B. Final Coating Latex (58% solids)
MaterialWt. Lbs.
1. Coating Grind (A), above 55.91
2. A commercially available vinyl53.03
chloride/vinyl acetate (90/10)
copolymer latex (56.5% solids)
3. Water 8.80
..
4. *Thickener solution (12.5% solids).72
5. *Water .83
119.29
_ _
*Premix 4 and 5 before addition.
The latex is applied to the fiber so as to deposit 4.0 ounces
thereof (solids) per square yard of fiber. I'he resultant coated fiber is
passed through a 325F. air circulating oven. Water is removed from the
coating and the resultant film is thereby set. ;~-
The coated fabric is removed from the device and the edges are
l evenly trimmed. A second vinyl chloride/vinyl acetate copolymer latex is then
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applied via an air knife, depositing 2.8 ounces thereof per square yard dry.
This second latex has th~ following composition:
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108S706
C. Coating Grind (67% solids)
Wt. Lbs.
1. Water 25.55
2. TiO2 slurry (67% solids) 48.86
3. Antifoam solution - 50% .20
CaCO3 47.50
5. Surfactant solution - 25% .40
6. Epoxidized tall oil plasticizer 4.99
127.50
D. Final Coating Latex (58% solids)
Material Wt. Lbs.
1. Coating Grind C, above 73.95
2. Same vinyl chloride/vinyl acetate 27.83
copolymer as B-2, above, (56.5%
solids)
3. Water 8.71
4. Thickener (12.5% solids) 2.60
113.09
The web is dried at 325F. in an air circulating, hot air oven while
still at about 275F. is fed between the crushing rollers of a calender at
300 p.l.i. pressure on the rollers. A smooth surface results. The surface is
set by chilling the web to 20F. The resultant web is rolled up and placed on
a gravure printing machine. A coating comprising a 20% solids solution of a
vinyl chloride/vinyl acetate (86/14) copolymer dissolved in a 70/30 acetone/-
methyl ethyl ketone solvent mixture is prepared. Carbon black ~0.5%~ is added
and the adhesive is deposited, using a gravure cylinder having a 55 l.p.i.
quadrahelic etch, at about 0.3 ounce per square yard, as a dry uniform coating.
The resultant material is preheated by passing it around a drum
heated to 320F. with the cotton back in contact with the drum. At a point
about one-third around the drum, the adhesive coated side is brought into
contact with a clear, 0.5 mil biaxially oriented film of polyethylene
terephthalate having on one side thereof a thin, vacuum deposited aluminum
layer. The aluminum layer is coated with a heat-sensitive adhesive of a vinyl
chloride/vinyl acetate/maleic acid (86/13/1) terpolymer. On the side of the
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1085706
terephthalate film opposite the aluminum layer is a 0.1 mil thick, clear
coating of a polyester adhesive.
The adhesive coated surface of the coated fabric is brought into
contact with the heat-sensitive adhesive face of the terephthalate film and
the two webs continue around the heated drum and are then passed between the
smooth rollers of a laminating nip press, the web temperature being controlled
at 270F.-310F. The nip rolls are chilled to 20F. and the two webs are
laminated together under a 400 p.l.i. pressure. The resultant material is
then immediately passed through additional cooling rollers to reduce it to
ambient conditions. The resultant material has a highly lustrous, metallic
finish of mirror-like appearance. -
The polyester coated-aluminum side of the laminated article is then
printed with a repeating striped design using black vinyl ink and a
conventional gravure printing cylinder and is dried. A commercially available
vinyl adhesive is then applied to the areas of the surface having the black
printed design thereon. The adhesive has the following composition~
Parts
1. Powdered vinyl resin (GEO ~ 124 or 100.00
128 - B. F. Goodrich Co.) ~ ;~
2. Epoxidized tall oil plasticizer 30.00
3. Isobutyrate solvent 30.00
4. Oil plasticizer 3.00
5. Organotin stabilizer 0.75
163.i5
The web is then passed under a hopper containing blue, short, rayon
flock fibers which are deposited thereon. The fibers are oriented by means of
a beater bar, the excess flock is vacuumed off and the adhesive is fused at
275C. A wallcovering of excellent thermal and dimensional stability, deep
gloss, metallic reflectance and scrubability is recovered. It is resistant to -
staining by crayon, fingermarks and oily grime.
EXAMPLE 2
The procedure of Example 1 is again followed except that the ~ -
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aluminum side of the laminated web is embossed before printing. An
aesthetically pleasing wallcovering results.
EXAMPLE 3
The procedure of Example 1 is again followed except that the
adhesive coating applied to the printed design is tinted light blue.
EXAMPLE 4
The procedure of Example 1 is again followed except that the black
printed design is eliminated. Similar results are observed.
EXAMPLE 5
(Comparative)
The procedure set forth in Bateman U.S. Patent No. 2,702,580 is
carefully followed in an attempt to produce a wallcovering in accordance
therewith. The procedure is as set forth in Example 1 thereof, Col. 1, line
76 to Col. 3, line 32, except as follows.
A) Due to difficulties in applying 0.5 ounce per square yard of the
base coating composition with a 20% total solids solution, the percent solids
was reduced to 10% by adding additional solvent.
,I B) The bone black particles employed were too large to give a smooth
surfaced coating so the solution was milled, ball mill jar fashion, at a 2 : 1
mixture to media ratio, for 24 hours. A smooth solution resulted. Some air
~ntrapment occurred in coating but no serious problems resulted. The solution
was knife coated to 12 mils.
C) The aluminized film adhesive was a vinyl chloride/vinyl acetate/-
maleic acid (86/13/1) terpolymer.
D) The cotton fabric had a thread count of 69 x 60 and weighed 3.9
ounces per square yard. This was the closest material commercially available
to that set forth by the patentee.
Comparative results of the procedures of Batemen vs. that of Example
1, above are as follows:
1. APPEARANCE
Immediately after lamination of the terephthalate film, the material
of Example 1 showed the characteristic telegraphing of the cotton fabric while
lV85706
the Bateman samples showed no telegraphing. None of the samples showed any
signs of self-delamination upon storage at room temperature, nor when heated
to 158F. for 72 hours did any surface defects appear. Viewed from the fabric
side, the material produced by the Bateman process showed that the base coat
had oozed therethrough while the material of Example 1 of the instant
application did not.
2. EMBOSSABILITY
The thermoplastic nature of the product shown by the Bateman patent
produced samples showing a very high emboss factor, rendering the sample
wrinkled and slightly distorted. Embossments in the Example 1 material were
excellent.
; 3. WASHABILITY
The washability test performed on the two samples was insufficiently
severe to cause any cleavage of the bonding of the articles. After 3000
cycles, only light to moderate wear was evident on either sample.
4. STIFFNESS
Stiffness was tested by both the single and double cantilever
methods, ASTM-D-1388-64. Both samples exhibited comparable stiffness. The
sample of Example 1, above, however, "felt" stiffer, the product of the patent
"feeling" like conditioned leather or rubber.
5. TENSILE STRENGTH
The greatest factor in determining the strength of the two samples
was the inherent strength of the terephthalate film itself. Since this film
was common to both samples, tensile testing was performed on samples that were
prepared up to but not including the terephthalate layer.
As was expected, the patentee's uncoated fabric was stronger. It
had a breaking strength of 52.5 lbs. for a 1 inch wide strip. The 30 x 30
uncoated fabric of Example 1, above, had a breaking strength of 10.6 pounds.
When the Bateman fabric was coated by the Bateman process, it showed a very
slight increase in strength and had a 6% increase in elongation. The coated
fabric of the instant invention doubled in strength, and was less elastic.
See Table 1, below.
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10195706
26,426 TABLE I
Fabric Coating Strength ~Lbs~ ion
30x30 None lQ.6 7~5
30x30 Ex. 1 above 21.7 5.1%
30x3Q Bateman 14.2 7.9%
56x60 None 52,5 13.0~
56x60 Bateman 52,6 19~2%
6. SCRUB TEST
The two samples were subjected to a hand scrub test
wherein each sample was scrubbed for 200 cycles. The test
was conducted by grasping the sample between the two hands
so that the thumbs were on top of the sample, parallel to
each other and 1/2 inch apart. The hands were then brought
together and scrubbed as if washing a fabric (Automotive
Industries, Dec. 20, 1973). The surface of the patentee's
sample was badly wrinkled while that of Example 1, above,
resisted surface wrinkling for a longer period of time.
EXAMPLES 5 & 6
The procedure of Example 1 is again followed ex-
cept that the fabric is (5) a polyester material and (6) a50/50 cotton-polyester material. Substantially analogous
results are achieved in each instance.
EXAMPLES 7, 8 & 9
The procedure of Example 1 is again followed except
that the fabric is (7) a non-woven spunbonded polyester material
weighing 1.0 ounce per square yard, (8) a non-woven rayon
material containing an acrylic latex binder and (9) a 70%
polyester-30% natural cellulose non-woven mat weighing 1.0
ounce per square yard. Substantially analogou~ results are
achieved in each instance.
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