Note: Descriptions are shown in the official language in which they were submitted.
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BACKGRO'JND OF THE INVENTION
Plastic material having a suede-like surface has been
prepared by a number of techniques. One process employed to
prepare commercial imitatlon suede material comprises the mech-
anical abrasion of the surface of a supported cellular plastic
layer (see U.S. Patent 3,041,193). Another process comprises
delaminating a cellular plastic layer along a section of the
cellular layer, such as along a plane of tensile discontinuity
between two foam layers, or by creating a plane of tensile
continuity through employing a temperature gradient, or by the
compounding of resins within a particular foam layer. This
latter process is described more particularly in U.S. Patent
3,709,752, issued January 9, 1973. Although these and other
processes have been employed to provide a suede-like material
suitable for use in belts, handbags, shoes and articles of
apparel, such as coats, vests, jackets, etc., such techniques
do not provide for the preparation of suede material in an easy,
efficient and economical manner, which material has an embossed
surface design thereon. A plastic material which has, in whole
or in part, a suede-like surface and which also has an embossed
design thereon, and is produced in an efficient and economic
manner, would be quite useful to provide different design pat-
terns and material, such as, for example, imitation corduroy-
like material.
SUMMARY OF THE INVENTION
our invention concerns an improved suede-like material
composed of a layer of cellular plastic having both a suede-like
surface thereon and an embossed surface thereon, and the method of
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preparing such materials. In particular, our invention relates
to an embossed suede-like plastic material comprising a layer
of cellular plastic composed of valley and peak areas and a
predetermined surface design thereon, with -the peak areas
having a suede-like surface, and with the density of the cells
beneath the valley areas being greater than the density of
the cells beneath the peak areas.
We have discovered a rnethod of preparing a unique
embossed suede-like plastic material, which method comprises
embossing under heat and pressure particular areas of a layer
of a cellular plastic material characterized by a suede-like
surface thereon. The embossing step is carried out to provide
an embossed surface in the layer of the wholly cellular plastic
composed of valley areas and peak areas which represent the in-
dentations and compressions of the cellular layer made by the
embossing roll or plate In our technique, the peak areas of
the resulting suede-like material are characterized by the
original suede-like surface, so that the cellular structure
beneath the peak areas is essentially the cellular structure
prior to the embossing step
The valley areas differ in cellular structure and
cell density beneath the valley areas due to the compression
of the areas in the embossing step. The valley areas are,
therefore, characterized by a slightly compressed cell-type
structure, such as an oval-type cell, and/or of a higher cell
density directly beneath the valley areas For example, the
cell density of the cells of the plastic layer directly beneath
the valley areas may be from about 50 to 200% greater in cell
density than the cell density beneath the peak areas. Of
course, the change of density is related to the amount of
pressure and heat employed in the embossing step, and may be
varied as desired. However, the heat and pressure employed
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in the embossing step should not be sufficient to change -the
cellular layer such as to compress completely and destroy sub-
stantially the cells which would change the area beneath the
valley areas in-to a solid, less flexible layer,
By employing an embossing step such that -the cellular
nature of the layer of cellular plas-tic is retained, the suede-
like material, supported or unsupported, continues to be very
flexible like natural suede, while unusual design and imitative
surface effects can be obtained. Of course, it is also par-t
of our invention that the suede-like surface material may have
a number of varying peak and valley areas of differing height
in order to impart varying design effects, so that the cell
density and cell structure beneath each area would vary, de-
pending upon the embossing step, the nature of the plastic
and the original nature of the cellular structure; that is,
whether open or closed and cell size.
In our process, the suede-like material to be embossed
may comprise any suede-like material which is composed of a
layer of a cellular plastic having a suede-like surface appear-
ance. Typically, the suede-like sheet material would comprise
a fibrous material, such as a woven fabric like cotton fabric,
having secured thereto a layer of cellular plastic with the
suede-like surface appearance. The plastic can typically be
composed of any plastic or polymeric material or resin which
is capable of forming a cellular layer and which is thermo-
plastic when subject to deformation during the embossing step.
However, the preferred material is a vinyl-halide resin, such
as polyvinyl chloride and vinyl chloride/vinyl-acetate resins
and similar types of vinyl-chloride resins which are plasticized
and cast or formed onto a supporting sheet. ~uring the em-
bossing step, the valley areas produced by the embossing are
altered in appearance and are less or nonsuede-like in appear-
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ance after such embossing; therefore, providing a contrast ;
between the raised suede-like surface of -the peak areas and
the nonsuede-like or smoother embossed surface of -the valley ~ `
- areas. Of course, if desired, the valley or peak areas, or
both, may be coated or printed to accentuate the differences
between the two areas to provide unusual design effects.
`` In our process, -the type and character of -the emboss-
!, ing plate or roll used may not have all of the mechanical
supports and requirements of typical embossing rolls and
plates, since the embossing is done under very li-ttle pressure;
i.e., merely sufficient pressure to compress -the valley areas
of a layer of cellular foam, if cellular foam under heat is
thermoplastic, so that the pressure may be little more than
con-tac-ting pressure in comparison to typical embossing opera-
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~ -tions where much higher pressure and heat are required. For
;~ example, the usual steel-engraved embossing roll may be em-
ployed or a design placed on the surface of a hard rubber roll.
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Our technique will be described in particular as an
improvement of the processes and products described in U.S `;~
; 20 Patent 3,709,7~2 wherein a suede-like plastic material is made
with a cellular surface composed of an undulating, irregular
surface composed of tensile-ruptured cells with short plastic ;~
fibrils on the surface -thereof, but which provides ~or a
surface having a suede-like appearance of or approaching that
of natural suede leather.
According to a broad aspect of the presen-t invention, --
there is provided an embossed flexible plastic suede-like -
- material which comprises a layer of a cellular plastic material
secured to a substrate sheet material. The cellular material
is characterized by a surface composed of embossed valley areas
and unembossed peak areas The peak areas are characterized by
a suede-like surface composed of tensile-ruptured cells. The
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cellular structure beneath the valley areas differs from the
cellular structure beneath the peak areas, and characterized by
a higher cell density, the valley areas having a smooth skin
surface layer formed of the embossed ceilular resin.
According to a further broad aspect of the present
invention, there is provided a method of preparing an embossed
suede-like plastic material, which method comprises embossing
under heat and only sufficient contacting pressure, particular
surface areas of a supported layer of a flexible cellular plastic
material characterized by a suede-like surface to provide a sur-
face composed of embossed valley areas and non-embossed peak
areas, the peak areas characterized by the original suede-like
surface, the cellular structure beneath the valley areas dif-
fering from the cellular structure beneath the peak areas, and
characterized by a higher cell density and the embossed valley
areas having a smooth surface skin layer formed of the plastic
by the embossing step.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. l is a schematic representation of a method
for preparing our suede-like plastic material.
Fig 2 is an enlarged cross-sectional and illustra-
tive view of a prior art sheet material used in the method of
Fig. l.
Fig 3 is an enlarged perspective partially cross-
sectional view of the suede-like plastic material prepared by
the method of Fig. l employing the material of Fig. 2
DESCRIPTION OF THE EMBODIMENTS
Fig 2 shows a prior art cellular laminate, such as
the type employed in the process described in U.S. Patent
30 3,709,7~2, to produce a suede-like plastic material, with a
suede surface composed essentially of tensile-ruptured cells,
which material lO comprises a woven fabric supporting sheet 12,
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a solid plastici~ed vinyl-chloride resin layer 14, a cellular
vinyl-chloride resin layer 16 and a thinner cellular vinyl-
chloride resin layer 18 and a paper sheet 20 bonded to resin
layer 18,
In Fig. 1, the laminate sheet material 10 is intro-
duced by a pair of opposing rollers 50 and 52 into contact
with the surface of a large steam-heated roller 56 heated, for
example, to a temperature of 250 to 350F, The woven fabric
12 side is placed against the surface of and is passed around
drum 56. Infrared heaters 54 direct infrared heat to the ex-
ternal surface o~ paper sheet 20, The paper sheet 20 and a
portion of the resin layer 18 adhering thereto is stripped
or delaminated from the remaining portion of the laminating
material 10 in the stripping or delaminating area 60, The
paper sheet 20 with layer 18 containing a tensile-ruptured
cell surface thereon moves by roller 58 to form roll 62, If
desired, the paper substrate can be replaced by a fibrous sub- -
strate as woven sheet 12, and then embossed in the manner set
forth hereafter to provide an embossed paper or fabric-supported
product as described.
The stripping and delaminating operation provides a
plane of tensile discontinuity in the resin layers 16 and 18,
and also provides a tensile-ruptured suede surface on layer
16 which gives it a suede-llke appearance, as well as a suede-
like surface on layer 18 on sheet 20.
The woven fabric 12, solid layer 14 and the cellular
layer 16 with the tensile-ruptured surface is then embossed -
on embossing roller 66 which lightly contacts the hot suede-
like surface of the cellular layer 16 -to impart a design effect ~;
30 thereon and to create raised peak areas and lower valley areas ;~
in the suede-like cellular layer. A printing roller 68 and
printing ink 70 are employed in order to place within the em-
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bossed valley areas a layer of printing ink to enhance the
embossed appearance of the finished article. The suede-like
article so embossed is -then removed through roller 72 and is
shown as a finished embossed material 30 A-t -the time of em-
bossing, the surface of the fabric is typically at about 275
to 300F, with the external paper surface at a lower temperature
of about 250 to 270F. The cellular layer 16 is adapted to
be compressed easily by the design on the embossing roller 66,
but little~ if any, pressure is required in the embossing
step In the embossing step as illustrated, the embossing
roller creates the valley areas, but does not apply any pres-
sure to the raised peak areas, leaving these areas with the
original suede-like surface, while compressing the cellular
layer in the areas beneath the valley areas to form a smooth
surface of continuous vinyl resin as a skin layer.
Fig. 3 shows an embossed suede-like material 30
prepared by our process and includes the woven fabric 12, a
solid vinyl-chloride plasticized layer 14 and peak surface
areas 32 having a tensile-ruptured suede-like surface appear-
ance thereon, and valley areas 36, with the thickness betweenthe peak and valley areas shown as 34 In the valley areas,
there is a printing ink layer 38 which may be colored or clear.
The cellular structure and cell density directly beneath the
peak areas 32 are in their substantially original form of
relatively uniform cell structure and original cell density
as in the preparation of the cellular layer prior to embossing.
The cellular structure and cell density of the cells 42 direct-
ly beneath the valley areas 36 are different from the cell
structure and density 40 beneath the peak areas in that such
areas, although still cellular, which is important to preserve
the flexible nature of our material, have cells which are
partially collapsed or compressed due to the embossing step,
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and also contain a grea-ter cell density than the cell density
in the areas 40.
The difference in cell density and cell structure,
however, does not affect the overall flexibility of the sheet
material as might be the case where complete compression and
destruction of the cellular areas took place, and a solid
layer was formed. In this embodiment illustrated, the emboss-
ing roll has been designed to impar-t an embossed corduroy effect
on sheet material 20. However, it is recognized that a number
of designs may be imparted to the suede-like material to pro-
vide various raised peak areas of textured surface throughout
the material, such as for the preparation of wall or surface
coverings
Our process has also been illustrated with the use
of an embossing roller; however, embossing plates or other
methods of forming the valley areas and the hot layer of the
cellular plastic of the suede-like surface may be used. When
using rollers as illustrated or plates, since the fabric or
supported sheet side of the suede-like material is at a high
temperature, the embossing roll should be maintained at a
lower temperature in order to prevent sticking and pulling away
of the cellular layer of plastic to the embossing roll. Where
another layer of cellular plastic which has a suede-like sur-
face is employed, such as a mechanically abraded surface, the
stripping and delaminating steps may be omitted and the
material merely passed about a drum and heated prior to the
embossing step.
As illustrated, a variety of embossing designs may
be imparted to the suede material If desired, the suede
material may be prepared in any manner, stored for a period of
time and subsequently embossed by reheating the material and
passing it through embossing rollers, although it is preferred,
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for economic reasons, -to carry ou-t the stripping operation
and subsequent embossing step in sequence, If desired, the
paper sheet 62 or a similarly produced fabric sheet as described
from the stripping step may be processed by embossing the
suede-like surface of the paper or fabric shee-t after the
stripping step, Such embossing may be carried out by the use
of an additional steam roller 56 and embossing rollers 66,
rather than winding up the material in a roll as illustrated,
Thus, from the laminate sheet 10, one or two supported embossed
suede-like surfaces may be obtained,
For the purposes of illustration, -the embossed
material has been shown as a supported thermoplastic material
with paper and fabric sheet materials, However, any sheet
substrate material may be used and bonded to the single and
multiple-layer foam sheet to be delaminated, In addition,
the suede material may be passed under heat and contacting
pressure through a series of embossing rollers to produce a
variety of surface design effects with valley areas of different
depth and structure,
Other modifications and techniques will be apparent
to those skilled in the art from our description and illustra-
tion of the invention,
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