U.S. patent number 3,874,958 [Application Number 05/381,442] was granted by the patent office on 1975-04-01 for method of making burned-out fabric.
This patent grant is currently assigned to VEB Plauener Spitze. Invention is credited to Sabine Fentos, Walter Scholtis, Wolfgang Stuber, Hans Wallisch.
United States Patent |
3,874,958 |
Scholtis , et al. |
April 1, 1975 |
METHOD OF MAKING BURNED-OUT FABRIC
Abstract
A method of making burned-out or etched patterned fabric,
whereby fabrics or filaments of a destructible material forming a
fabric with indestructible fibers or filaments, is removed by the
patterned application of an etching agent and the subsequent
activation thereof by heating. The improvement resides in providing
the removable filaments as mats of unspun filaments incorporated
into a mesh of the nonremovable filaments.
Inventors: |
Scholtis; Walter
(Karl-Marx-Stadt, DL), Wallisch; Hans (Frankenberg,
DL), Stuber; Wolfgang (Plauen, DL), Fentos;
Sabine (Plauen, DL) |
Assignee: |
VEB Plauener Spitze (Plauen,
DT)
|
Family
ID: |
23505036 |
Appl.
No.: |
05/381,442 |
Filed: |
July 23, 1973 |
Current U.S.
Class: |
216/7; 216/55;
8/114.6; 26/69B; 156/85; 428/187; 8/115; 28/163; 156/155;
428/543 |
Current CPC
Class: |
D06Q
1/02 (20130101); D04B 21/165 (20130101); D04B
1/123 (20130101); Y10T 428/8305 (20150401); Y10T
428/24736 (20150115) |
Current International
Class: |
D06Q
1/02 (20060101); D06Q 1/00 (20060101); D06q
001/02 () |
Field of
Search: |
;156/2,7,155,85,93
;28/76R ;161/97 ;8/114.6,115 ;117/11 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Powell; William A.
Attorney, Agent or Firm: Ross; Karl F. Dubno; Herbert
Claims
I claim:
1. A method of making a patterned fabric comprising the steps
of:
combining a body of unspun fibers capable of being dissolved by an
etchant with at least one filament not dissolvable by said etchant
into a fabric;
locally printing said fabric with a paste of said etchant according
to a pattern;
heating the printed fabric to etch away said fibers in the regions
covered by said paste; and
shrinking said filament after etching of said fabric.
2. The method defined in claim 1, further comprising the step of
mixing with the etchant-dissolvable fibers fibers which are not
etchant dissolvable.
3. The method defined in claim 1 wherein two differently etchable
fibers are used and two different etching pastes are used.
4. the method defined in claim 1 wherein said fibers are viscose
fibers.
5. The method defined in claim 4 wherein said etching paste is an
aluminum sulfate compound.
6. A method of making a patterned fabric comprising the steps
of:
combining a body of unspun fibers capable of being dissolved by an
etchant with at least one filament not dissolvable by said etchant
into a fabric;
locally printing said fabric with a paste of said etchant according
to a pattern; and heating the printed fabric to etch away said
fibers in the regions covered by said paste, said body of unspun
fibers being stitched through with rows of stitching and the rows
of stitching being provided in 15 to 30 stitch rows per 25 mm of
transverse width, the stitch length of the stitches of each row
being 0.5 to 1 mm and said unspun fibers having a length of at
least 100 mm.
7. The method defined in claim 6 wherein said filament is composed
of a thermally fixable synthetic resin and said paste is thermally
activatable said fabric being heated to a temperature sufficient to
activate said paste and thermally fix said filament.
8. The method defined in claim 7 wherein said body of unspun fibers
is provided in least two superimposed layers.
9. The method defined in claim 7 wherein said body of unspun fibers
contains a minor proportion of fibers unaffected by said etchant.
Description
FIELD OF THE INVENTION
The present invention relates to a method of making burned-out
fabrics of the type wherein localized destruction of a portion of
the fabrics of a fabric web are destroyed and removed to leave a
pattern corresponding to that of the localized removal of fabrics.
More particularly, the invention relates to an improved method of
making etched or burned-out fabric and to a technique for obtaining
burned-out fabric at lower cost and with higher quality than has
been possible heretofore.
BACKGROUND OF THE INVENTION
In the production of burned-out fabric or etched fabric, it is
known to apply an etchant adapted to dissolve or otherwise remove
fabrics or filaments of one chemical composition directly or after
thermal activation, to a web containing these etchable or
destructible fabrics or filaments incorporated in a fabric of
nonetchable or nonremovable fabrics or filaments. When the etching
step is completed, the portion of the web to which the chemical
etchant was applied contains only the nonetchable fabrics or
filaments while those areas to which the etchant was not applied
contain both the etchable and nonetchable fabrics and filaments,
thereby imparting a texture or pattern to the web. When the
etchable fabrics are colored or obscure a color of the base or
nonetchable fabrics, the patterning operation may produce color
patterns as well as texture patterns and, indeed, both a sculptured
effect and a color patterning are customarily obtained.
The web is generally a textile fabric which is woven, netted or
otherwise produced from continuous filaments or yarn (spun fabric)
of the two types or a textile fabric produced from a spun yarn
containing both types of fabric.
In general, the prior-art technique comprises the formation of a
web or textile fabric, with or without individual yarn inlay,
consisting of two different yarn types, at least one of which
consists of or contains an etchable fabric or filament while the
other yarn or filament components is nonetchable. It has been found
to be desirable, with the earlier systems mentioned above, to use
fine-gauge material, tight weaves or knits, and close spacing of
the warp and weft threads of a weave and of wales and courses of a
knit, to maintain a substantially closed surface at locations at
which the etchable filaments are removed. Even the etchable
filaments, therefore, must be of fine gauge and relatively high
cost, in spite of the fact that the etchable filaments are at least
in part destroyed or removed. When coarse spun filaments, fabrics
or yarn of the etchable material are employed, difficulties are
experienced in holding the fabric web together in the burned-out
region because of the precipitation of the spun yarn of etchable
material in the fabric construction. It has also been found that
such webs create problems with respect to the speed of etching, the
controllability of the etching step and/or the degree of
etching.
In the following description we will use the term "burn-out" to
describe a chemical etching process whereby a pattern can be formed
in a web by the localized destruction, solubilization or
decomposition of said fibers and filaments, hereinafter referred to
as "etchable" fibers or filaments. The term "unspun" is used herein
to refer to filaments or fibers which are discrete, i.e.
non-twisted, and the term "spun fibers" or "spun filaments" is used
to identify normal yarn made up of one or more filaments twisted or
spun together.
The patterned fabric (with respect to texture, color or both) made
by the burning-out process of the present invention, can be
employed for any purpose in which conventional etched fabric has
been used heretofore, e.g. for drapes, curtains, upholstery,
carpets and garments, but finds particular utility as synthetic fur
when at least one surface is brushed up or roughened to provide a
nap.
OBJECT OF THE INVENTION
It is the principal object of the present invention to provide an
improved method of making an etched-out or burned-out fabric
whereby the aforementioned disadvantages are obviated.
Another object of the invention is to provide a low-cost method of
making high-quality patterned fabrics.
SUMMARY OF THE INVENTION
These objects and others, according to the present invention, are
attained by the formation of a reticule (mesh) of nonetchable fiber
and filaments in which is anchored a nonwoven, nonknitted mat of
unspun etchable fibers or filaments (fleece) which may be locally
removed by chemical techniques as employed in conventional burn-out
methods.
The invention is based upon our surprising discovery that it is
possible to incorporate a nonwoven and nonknitted body (fiber
fleece) of unspun filaments of an etchable material having a fiber
length greater than 100 mm in a reticulate structure, preferably
formed by stitched loops or closely spaced rows of stitching, so
that the subsequent etching process (localized) can remove the
unspun filaments or fibers or a substantial portion thereof, while
leaving a patterned web of high mechanical integrity. One normally
would expect, especially where the reticulate structure is formed
by closely spaced rows of machine stitches piercing the fiber
fleece or mat, the that destruction or chemical solubilization of
the fiber fleece would result in deterioration of the mechanical
properties of the web since a substantial part of the material
which cross-connects the rows of stitching is removed in the
etching process. It has been found, however, that burn-out
patterning as conventionally employed does not have this effect,
presumably because the burn-out process does not remove all of the
etchable fibers (which may extend randomly in the fiber fleece or
mat and hence include fibers running transverse to the rows of
stitching), which remain in the fabric to retain the rows of
stitching together.
Advantageously, the burn-out process is accompanied by a
thermofixing of the nonetchable fibers or filaments (preferably a
spun yarn) to further prevent deterioration of the strength
characteristics of the fabric in the burn-out region.
The resulting patterned fabric may have a sculptured or a textured
patterning or a color patterning or both, as noted above.
The reticulate or mesh structure in which the fiber fleece is
lodged is preferably, as noted, a fabric formed by closely spaced
rows of stitches (e.g. chain stitches) with or without crossing
filaments or fibers. This fabric, in which sewing-type stitches
form the mesh, when provided with a fiber fleece as previously
described, will be referred to hereinafter as a fleece/stitched
fabric.
According to the invention, therefore, the fabric has a
destructible component of unspun fibers in the form of a nonwoven
fabric strip, sliver or roving, consisting in whole or in part of
the destructible yarn. The destructible component may also be
provided in the form of unbundled fibers (a random mass which
becomes somewhat matted), bundles, tufts and the like.
Presumably, fabrics containing fiber fleece have not hitherto been
considered useful for making etch-out or burned-out fabrics because
it was assumed that the longitudinal stability depended solely upon
the characteristics of the sewing filaments while the only
transverse stability was solely provided by the mat. When such
systems were subject to patterned etching, transverse stability was
lost entirely and the fabric had no stability. Surprisingly, when
the fibers or filaments of the destructible component have a fiber
length in excess of 100 mm and the transverse spacing of the stitch
rows ranges between 15 stitch rows per 25 mm and 30 stitch rows per
25 mm, the deterioration of the fabric upon patterning is avoided
entirely. The stitch length may range from 0.4 to 1 mm.
According to another feature of the invention, the fleece/stitch
fabric is locally printed or padded with a printing paste
containing a chemical component adapted to react with the etchable
fibers or filaments directly or under the influence of an applied
temperature (heating) to effect decomposition of the removable
filaments. In general, the localized etchant can consist of etching
sulphates, i.e. aluminum sulphate, or strongly oxidized materials
such as benzoylperoxide. At the elevated temperatures the aluminum
sulphate or benzoylperoxide decompose the etchable fibers which can
then be leached from the fabric to leave the nonetchable threads or
fibers in the locations at which the fabric had been printed with
the etachant.
While the invention has been said to be applicable particularly and
preferably to fleece/stitched fabrics, other fabric webs in which
the nonspun and nontwined etchable fibers are incorporated in a
mesh structure, may be used. Such other fabrics may include weft
knits and circular knits, in which the unspun etchable fibers are
laid in as sliver or bands.
The technique of the present invention can produce relatively light
nontransparent materials and various patterning effects not
hitherto possible. By eliminating the spinning or twisting process
for the etchable fibers, the cost of the production is reduced and
the different patterns which can be generated are increased. The
etchable fibers are preferably composed of viscose rayons or
cellulose fibers (hereafter described as viscose fibers), with
which a minor proportion (less then 50%) of other fibers such as
polyacrylonitrile fibers, which may be etchable in a second step or
completely non-etchable, may be combined.
The method according to the present invention allows the production
of completely novel fabrics. Since the spinning and twisting
process is eliminated (for the etchable fibers, as noted above),
not only is the finished product cheaper to make, but it can have
patterns hitherto unattainable. For instance when viscose fibers
are mixed with a small percentage of coarse-titer fibers, such as
polyacrylnitrile fibers, the etched out regions of the finished
product will be particularly well defined. The use of two different
etchable fiber components allows various surface effects, e.g. the
simulation of fur, to be achieved with ease.
Other effects can be achieved, for example, by combing up the
unetched fibers and then etching some of them away. Two different
fiber components can be used and one or the other, or both, can be
etched away to produce a three-part pattern. A product closely
resembling lace can be produced if desired by using shrinkable
filaments in the web, and carrying out a shrinkage step for those
filaments after etching.
DESCRIPTION OF THE DRAWING
The above and other objects, features and advantages will now
readily become apparent from the following description, reference
being made to the accompanying drawing in which:
FIG. 1 is a diagrammatic view illustrating the process according to
the present invention;
FIG. 2 is a plan view of a piece of fabric etched according to the
present invention;
FIG. 3 is a diagrammatic plan view of a fleece/stitch fabric
according to the invention;
FIG. 4 is a cross-section through this fabric, drawn to an enlarged
scale and taken generally along the line IV--IV of FIG. 3;
FIG. 5 is a view of the fabric of FIG. 3 burned-out along a
diagrammatic pattern;
FIG. 6 is a view similar to FIG. 3, showing another fabric
according to the invention;
FIG. 7 is a view similar to FIG. 5, showing the burn-out fabric of
FIG. 6, also with a diagrammatic pattern;
FIG. 8 is a section generally similar to FIG. 4 but illustrating
another embodiment of the invitation;
FIG. 9 is a view similar to FIG. 4 and illustrating still another
fabric construction according to the invention;
FIG. 10 is a plan view showing the burned-out fabric of FIG. 9
after a first etching stage; and
FIG. 11 is an enlarged cross-sectional view showing a brushed-up
fabric according to the principles of this invention.
SPECIFIC DESCRIPTION
As shown in FIG. 1 etchable or destructible fibers from a supply
10, other less or even nonetchable fibers from a supply 9, and an
unetchable or relatively indestructible filament from a supply 11
are combined in a knitting, weaving, or meshing machine 12 to
produce a continuous striped fabric F. This fabric is then printed
with an oxidizing or etching paste at a printing station 13 after
which the fabric is passed through a thermal-treatment station 14
where the printing paste applied in station 13 is activated and
destroys the filament it is printed on. Thereafter the fabric is
washed and rinsed at a washing station 15 and dried and even beaten
or brushed up, if necessary, in a drying station 16.
The finished product is shown in FIG. 2. This fabric has a
continuous surface 17 in which are etched holes 18 where only the
web or mesh formed by the filament 11 is present. Such a fabric is
useful for dresses, drapes and similar purposes calling for an
interesting pattern.
In FIGS. 3 and 4 we show an embodiment of the invention wherein the
fleece/stitch fabric 20 comprises a layer 21 which is non-woven and
non-netted, i.e. consisting of a mat of pile non-oriented and
compressed unspun fabrics having a minimum fabric length of 100 mm
and being composed of an etchable material. The mat 21 is stitched
through with rows 22 of stitches 23, the spacing D between the rows
being of the order of 0.5 to 2 mm so that between 15 and 30 stitch
rows are provided for each 25 mm of width of the fabric. The
stitches (FIG. 4) having a stitch length L which ranges from 0.4 to
1 mm may consist of upper threads 24 and lower threads 25 locking
the etchable unspun fiber between them. When the fabric is printed
with, for example, a diamond pattern of an etchant, the fabric is
heated to activate the etchant and thermally fix the stitches 23 at
their junctions 26, the subsequent leaching step will remove the
unspun fibers in the diamond-shaped area 27 which is spanned by
closely spaced chains of stitching thread 28 in the form of loops.
A tricot stitching pattern may, of course, also be used.
In FIGS. 6 and 7, we show a system in which the stitches 33
piercing the mat 31 of unspun filaments are chain stitches while
the mat is composed in part of filaments which are nonetchable (39)
and are shown to interconnect the rows 38 of stitches after
leaching. FIG. 8 shows that the nonwoven mat 41 of etchable unspun
filaments (and a small proportion of unspun nonetchable filaments
if the construction of FIG. 7 is to be obtained) is anchored by
rows 42 of stitches to a support fabric which may be a fine weave
or knit and is represented at 45. In addition, or alternatively,
the mat can constitute two or more layers 51a and 51b held in place
by superimposed rows of stitching 52a and 52b so that an underlying
mat layer 51a is exposed after the overlying layer 51b is removed
by etching. This newly exposed layer can be removed in a separate
etching operation. FIG. 11 shows that the fibers 60 can be brushed
up through the reticulate structure formed by the rows of stitches
62 to impart a fur-like texture to the cloth in those regions in
which the nonwoven fabric layers are not removed.
EXAMPLE I
Fleece/stitched fabric is made of viscose fibers with a staple
length of 100 mm and a weight of 420 mtex (3.75 denier), and
polyamide silk of a 5 tex mm (Nm 200) weight is used. This fabric
has a weight of 100 g/m.sup.2, with a gauge of 22F (22 needles/25
mm), or mm 88 wales per decimeter, and a stitch length of 0.63 mm.
The fleece is stitched over in a tricot pattern.
The fleece knit so made is washed, bleached, and optically
brightened. Then it is printed with a paste which is thickened with
a galactomannitol and which contains 150 g/kg of aluminum sulfate
and is allowed to dry. A local coloring of the polyamide filament
can be achieved by the addition of a dispersion dye to the printing
paste. Then the fabric is clamped in a tenter frame and heated to
190.degree.C for about 30 seconds so that the aluminum sulfate
destroys the viscose fibers. Simultaneously, the polyamide
filaments are thermally fixed and the dye is irradiated. The
destroyed viscose fibers are removed by washing the fabric for 30
minutes in a 50.degree.C solution of 2 ml/l sodium hydroxide
38.degree. Be. Then the fabric is rinsed in a solution of 1 ml/l of
80% acetic acid, then extracted, dried and even beaten, if
necessary.
The product has closed regions formed by the overstitched viscose
fibers and transparent regions which are constituted only by the
tulle-like net of the polyamide tricot.
EXAMPLE II
A fleece fabric formed of 95% viscose fibers, 420 mtex (3.75
denier), having a staple length of 100 mm and 5% polyacrylonitrile
fibers, 1,700 mtex (15 denier) and of a 100 mm staple length, as
well as polyamide silk 5 tex (Nm 200), as stitching filament. The
fabric has a weight of 100 g/m.sup.2 with a fineness of 22F and a
stitch length of 0.51 mm. The fleece is overstitched in tricot
fashion and the fabric is printed with a paste as described in
EXAMPLE I, above. The viscose fibers are similarly treated
thermally and removed.
The end result is that the polyacrylonitrile fibers remain in the
regions where the viscose fibers are etched out so as to produce a
sharply defined pattern in the laid in coarse-titer
polyacrylonitrile fibers.
EXAMPLE III
Fleece fabric made of a mixture of 50% dull acetate fibers, 340
mtex (3 denier), 100 mm staple length, and 50% shiny viscose
fibers, 420 mtex (3.75 denier), 100 mm staple length, stitched in
polyamide silk 5 tex (Nm200), with a mesh fineness of 22F. The
fabric has a mass of 120 g/m.sup.2 and a stitch length of 0.64 mm,
with a tricot knit.
This fabric is printed according to the pattern with either or both
of the following two pastes, which one or whether both are used
being dependent on the pattern effect desired:
a. 200 g benzyl peroxide
200 g benzyl acetate
600 g tragacanth thickener
b. 150 g aluminum sulfate
150 g water
700 g galactomannitol base thickener
The paste a removes the acetate fibers, the paste b the viscose
fibers.
After printing, the fabric is treated as described in EXAMPLE I and
the destroyed fibers are removed in a subsequent beating and
washing step.
The finished product resembles lace which is overlaid with
polyamide silk and has dull acetate fiber regions and shiny
viscose-fiber regions.
EXAMPLE IV
A fleece fabric is made of 30% highly shrinkable polyester fibers
340 mtex (3 denier), of 60 mm staple length and 70% viscose fibers
420 mtex (3.75 denier) held in a mesh of highly shrinkable
polyamide filament. This fabric has a weight of 90 g/m.sup.2. The
fleece is stitched over with a fineness of 22 F and a stitch length
of 0.83 mm.
The viscose fibers in the fleece are removed by heat after printing
with aluminum sulfate as described above.
Subsequently, the so-etched fabric is shrunk by a 30 second contact
with a 95.degree.C roller so as to fully shrink the polyamide and
polyester which are already somewhat shrunk by the thermal
treatment used in printing. This produces a fabric which is more
crimped in the regions where the stitches are not full with the
fibers, then in the filled regions, so that a relief effect is
achieved.
EXAMPLE V
Fiber bands are produced on a carding machine from a mixture of 50%
acrylic fibers and 50% acetate fibers with a mass of 10 g/m.sup.2.
These fiber bands are fed to the miniature cards of a fiber-band
knitting machine wherein the miniature cards are arranged around
the needle cylinder of the machine so as to reduce the bands to
fibers and feed these fibers to the needles. The fibers are laid
into a base knit formed by the knitting machine from cotton 20
.times. 2tex (Nm 50/2). The fiber band knit is subsequently printed
in a pattern with a paste made of:
200 g benzyl peroxide
200 g benzyl acetate, and
600 g tragacanth thickener.
Then the fabric is dried and treated for 30 seconds in a tenter
frame at 190.degree.C.
The finished product is an imitation fur with a relief surface
effect due to the partial etching-away of the acetate fibers.
* * * * *