Note: Descriptions are shown in the official language in which they were submitted.
-~ ` 1093~50
BACKGROUND
FIELD OF THE INVENTION
This invention reIates to primary backing for tufted
carpets and carpets made therefrom.
PRIOR ART
A tufted carpet has at least two parts. The first
is a primary backing and the second is tufted pile loops
which usually pass through and are supported by said primary
backing. In a tufted-carpet, pile loops either cut or uncut
project from one side and are usually connected by loops on
- the reverse or floor side.
Fine gauge tufting in the art implies tufting with
about 10 or more tufting needles per inch in the weft direction.
Fine gauges generally run from about 1/10" to about 1/20",
- wherein in the weft direction 1/10" corresponds to 10 tufting
needles per inch and 1/20" corresponds to 20 tufting needles
per inch. Piie heights, deniers, and stitches per inch in
the warp direction-so vary from style to style, that no
- exhaustive correlation to fine gauge tufting can be made.
Generally, in fine gauge tufting, pile heights are in the range
rom 3 mm to about 15 mm; pile deniers are in the range 75 tex
to about 250 tex, but texes as high
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~93450
as about 300 are not unknown, and stitches per inch in the warp
direction are in the range of about 8 to about 20. As the gauges
become fin~r and pile heights shorter, any discontinuities aris-
ing from either needle or tape deflection become aesthetically
very noticeable.
Woven-tape or woven slit film substrates such as dis-
closed in T. M. Rhodes (cited later) modified to include multi-
filament weft fibers give rise to an improved primary backing
for use in fine gauge tufted carpets. However, many aesthetic
problems arising from insufficient pile uniformity still occur.
The stability of the tufted substrate is generally not sufficient
to avoid bowing and skewing during dyeing or applying a foam
backing. It is to be noted that distortion of the dyed image in
fine gauge tufted carpets generally has a more critically adverse
impact on the aesthetic appearance of said carpet than in other
types of tufted carpets.
It is to be noted that attempts to stabilize the woven
substrate by the application of adhesives so as to overcome the
above cited problems often has an adverse impact on the tufting
process and for that reason have been generally unsuccessful.
With the advent of synthetic primary backing such as
disclosed by H. A. Schwartz et al. in U.S. 3,359,934 (1967) and
by T. M. Rhodes in U.S. 3,110,905 (1963), the dyeability of the
primary backing in general, and those made from polyolefins,
such as polypropylene and polyethylene resins and the like in
particular, has become a concern. The reason for this concern is
that if the substrate is not dye-compatible with the pile fibers,
i.e. does not accept the same dye-stuffs as the pile fibers,
then the substrate will shadow light and detract from the overall
light reflectance desired. Also the carpet will lack the
desired uniform coloration and pattern clarity after pattern
deep dyeing. For purposes of discussion, both of these undesir-
,. - - - ' :
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93~.~iO
able aspects of a substrate which is not dye-compatible with the
pile loops will be referred to as "grinning" problems.
Of the many methods tried to solve grinning problems,
only needlebonding of a fiber dye-compatible with the pile loops
in sufficient quantities to form a thin subsurface of fibers which
visually covers said substrate has had widespread commercial
success. The method of needlebonding a substrate is disclosed by
R. H. Kimmel, et al. in U.S. 3,605,666 (1971). A primary backing
made by this process of needlebonding will throughout this
Specification be referred to as an FLW primary backing. FLW are
initials for fiber lock weave. It is to be noted that the reason
for using different types of fibers for the substrate from those
used in the pile loops is dictated by commercial considerations,
in that the dyeable pile loops generally are much more expensive
than the material used to form the substrate of the primary
backing.
There are however several disadvantages to both the ~
manufacture and performance of FLW primary backing. These are: ~-
(1) production speeds for the needling process are very adversely
affected by decreasing fiber deniers, increasing web weights, and
increasing number of needle punctures/inch and also there is a
substantial amount of noise associated with the needling process;
(2) some of the effective covering power of the needled fibers
is lost due to a portion of the needled fibers pro~ecting through
to the back of the substrate; (3) there is a tendency for some
of the fleece fibers to work their way out of the FLW primary
backing (fiber bleeding) with adverse affects on the performance
and appearance of the finished carpet; (4) even though a greater
cover power/web weight of pigmented, dyed or dye-compatible
fibers occurs with increasingly fine deniered or low cross-
sectional area fibers, in practice the cross-sectional area of
the fibers in the needling process are limited, because the
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` ` 1093450
`finer the fiber the slower is the process of needlebonding;
(5) tuft lock (as measured according to ASTM D 1335-67) is re-
duced in a primary backing material which has been needled prior
to tufting; and (6) the overall tensile strength of a tufted
primary backing is reduced by the needlebonding process.
It is an object of this invention in some of its embo-
diments to provide a primary backing for fine gauge tufted car-
pets which overcomes many of the above described problems
associated with fine gauge tufting.
It is an object of this invention to provide a method
and article of manufacture suitable for primary backing for
tufted carpets and carpets made therefrom which obviate the
limitations associated with FLW primary carpet backings and
their method of manufacture.
It is an object of this invention to provide an article
suitable as a primary backing for tufted carpets which uses
substantially less dyeable, pigmented, or dyed subsurface or
fleece fibers than an FLW primary backing to achieve an equal
degree of visual cover or cover factor.
It is an object of this invention to provide a primary
backing for tufted carpets wherein the subsurface fibers have
both a higher peel strength and substantially less tendency to
fiber bleed than those found in FLW primary backing.
It is an object of this invention to provide a primary
backing for tufted carpets which has higher overall tensile
strength subsequent to a tufting and/or dyeing operation than an
FLW backing.
Other objects will be clear to a man of skill in the
art after reading this Specification.
BRIEF DESCRIPTION OF THE INVENTION
-
It has been found that the above objects can be
accomplished by a method comprising forming a web or fleece of
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` --``' 1()~34SO
fibers on a woven, non-woven, or knitted substrate by means of
conventional web-forming machinery such as is obtainable from
Hergeth AG, Maachinenfabrik und Apparatebau Duelmen FRG, wherein
said web is heat fusible to said substrate, and heat fusing said
web to said substrate. Heat fusible throughout this Specifica-
tion and Claims is defined to mean capable of forming a bond
under the influence of both heat and pressure. The web generally
consists of a blend of two fiber components, the first, which
can at least in part be dyed, dyeable, coated, pigmented, or the
like, is heat fusible to said substrate at a temperature which
is equal to or below the heat or melt fusion temperature of the
substrate and which is beneficially also below and preferably
at least about 5F below the melting point (as determined
according to ASTM D 2117-64) of a second fiber component in the
blend. The second fiber component is preferably at least in -~
part dye-compatible with tufted pile loops which are later to be
introduced to form a tufted carpet. The second fiber component
can also be at least in part a dyeable or pigmented fiber not
itself melt or heat fusible to said substrate. The first fiber
component provides either the bonding of the second fiber com- ~ ;
ponent in the web to said substrate and/or in addition to and/or
in the absence of the second fiber component, color coverage to
the substrate. Component is throughout this Specification and
CIaims intended to indicate the possibility of one or more
different fibers of the same class, i.e. either heat fusible with
a substrate, an example of a fiber in a first fiber component,
or not heat fusible with a substrate, an example of a fiber in a
second fiber component.
Methods for preparing a dyeable fiber, such as for
example a polyolefin fiber, by means of incorporating therein a
dye receptive additive are given in U.S. Patents 3,819,758 (1974);
3,834,870 (1974); 3,820,949 (1974); and 3,926,553 (1975).
,: -. . .
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10934S0
Methods for preparing a pigmented fiber, such as for
example a pigmented polyolefin fiber are well known in the art.
It is to be noted that generally the substrate alone
is capable of being tufted and the weight per square meter of the
fiber web bonded to said substrate will be preferably as small
a weight as possible and still provide as much dimensional sta-
bility as required in subsequent steps of carpet manufacture as
well as sufficient coverage to avoid significant grinning
problems. Generally, said fiber web will not be tuftable unless
bonded to said substrate. A substrate which alone i9 not capable
of being tufted must become so capable after a fiber web has
been bonded thereto.
In general, the greater the weight percent of bonding
fiber based upon total web weight, the greater will be the peel
strength. The denier and length of the fibers within the web
are in part limited by the problem of cloudiness which is des-
criptive of the non-uniformity of a carded web as is known in
the web forming art. Fiber lengths substantially greater than
150 mm can be used provided that sufficiently large deniers are
used. As the denier of a fiber approaches 1.2 dtex, and its
length becomes increasingly longer than 150 mm, cloudiness
becomes an increasingly larger problem.
A method for producing an article suitable for use as
a primary backing for carpets having tufted pile loops comprises:
(1) forming a web onto a woven, nonwoven or knitted sub-
strate capable of being tufted with pile loops ranging
from coarse to fine in both denier and gauge, wherein
said web comprises about 5~ to 100~, and preferably,
about 15% to 100% by weight based on the total weight
of the web of a first fiber component which is heat or
melt fusible to said substrate and can be at least in
part dyeable, pigmented or dyed and which has a denier
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~ `-` 10~34S0
of at least about 1.2 dtex and a fiber length of at
least 5 millimeters, and about 95% to 0.0%, and
prefera~ly, about 85% to 0.0~ by weight, based on the
total weight of the web, of a second fiber component
which can at least in part be either dye-compatible
with said tufted pile loops, dyeable, or pigmented and
which has a denier of at least about 1.2 dtex and has
a fiber length of at least 5 millimeters;
(2) applying heat and pressure so as to produce both a
bond between said first fiber component and said sub-
strate, and, where a second fiber component is used,
a bond between said first fiber component and said
second fiber component, whèreby said web is bonded to
said substrate.
Web weights in general are preferably as low as pos-
sible, while achieving sufficient dimensional stability as well
as coverage to avoid substantial grinning problems. A web
weight per square meter of at least 3 g is usually necessary.
Web weights per square meter found satisfactory are generally
in the range of about 3-70 grams, and preferably in the range
of 5-50 grams.
The gram ranges in web weight per square meter for
commercial FLW backing are about 33 to about 135 grams. The web
weight to achieve a particular level of coverage clearly depends
in part upon the deepness of the color from the dye or pigment
used in the fibers present in the web. In view of the enhanced
coverage achievable by means of this invention, over FLW, parti-
cular advantages accrue from use of web weights below about 25
grams per square meter.
Said second fiber component comprises fibers which are
not heat fusible to said substrate, so that only bonds between
said first fiber component and said second fiber component can
`~
~ ~9~50
occur.
In general, any substate, woven, nonwoven, or knitted
capable of being tufted to which heat fusible thermoplastic fibers
can be heat and pressure bonded can be used. Examples of thermo-
plastic substrates useful in this invention are in general poly-
olefins, polyamides, polyesters, vinyls, and acrylates.
Woven substrates having fibers preferably flat and
rectangular in cross-section of 200 to 1500 dtex in both the
warp and weft with 10 to 30 counts per inch in the warp and 5 to
30 counts per inch in the weft are particularly useful. An
example of such woven substrates can be found in T. M. Rhodes.
In the case of fine gauge tufted carpets, said woven substrates
preferably employ multifilament yarn having single filaments
between about 2 and about 20 dtex with round or multilobal
cross-section. The multifilament yarn preferably has a
producer's twist of about 10 to 20 turns per meter. It has been
found that the fine gauge tuftability can in general be improved
by heat fusing a layer of fibers to said substrate, and a
particularly useful primary backing for fine gauge tufted carpets
can be made by means of this invention.
One method for applying heat and pressure is to use a
nip created between two counter-rotating rolls. The roll con-
tacting a side of said substrate covered with a fiber web is
heated to a temperature sufficient to cause heat fusion between
the first fiber component, i.e., the heat fusible fiber component~r
and the substrate, and if there is a second fiber component
; present, to cause a bond between said first fiber component and
said second fiber component without severely softening said
second fiber component, i.e., said temperature is below and
preferably at least 5F below the melting point of said second
fiber component. If for example a polyamide-6 fiber and a fiber
and a substrate of polypropylene or other polymer made from one
' ' ,' ~ ~ ' . ~
1093450
or more l-olefins having up to 8 carbon atoms or the like are
being used, then said temperature is in the range of about 160C
to 200C, i.e., the melt fusion temperature range for poly-
propylene. The other of said counter-rotating rolls contacts
the uncovered side of the substrate and is heated to a tempera-
ture in the range of about 0 to 160C, and the linear pressure
in said nip can be up to about 350 Kp per linear centimeter.
The linear rate of speed of said substrate in the machine direc-
tion through said nip is in a range of up to about 60 meters per
minute.
Several arrangements involving both plain or embossed
rolls can be employed to form said nip. In a first arrangement,
a plain steel or chromium plated roll contacts a side of the sub-
strate covered with a fiber web or fleece and either an embossed
roll or a plain roll with a flexible or deformable surface con-
tacts the uncovered side of said substrate. An example of such
a deformable surface is one covered with cotton paper. In this
first arrangement, pressures preferably range from about 180
Kp/linear cm. to about 300 Kp/linear cm. With a pressure much
below 180 Kp/cm., the fiber web does not adhere well to the sub-
strate, but with a pressure much above 350 Kp/cm., the substrate
can be adversely affected. In a second arrangement, an embossed
roll contacts a side of the subsirate covered with a fiber web
or fleece and the opposite side is contacted with either a plain
steel roll or one having a deformable surface, such as for example
a cotton-paper surface. In the second arrangement, pressures
preferably range from about 20 Kp/linear cm. to about 180 Kp/
linear cm. With a pressure much below 20 Kp/linear cm., the
fiber web does not adhere well to the substrate, but with a
pressure much about 180 Kp/linear cm., the substrate can be
adversely affected. In general, the number of bosses of the
embossed roll in both arrangements is in the range of about
~ ~ _ g _
: , . .
10~33450
20-80 bosses/cm.2 and preferably about 30-50 bosses/cm.2 provid-
ing an effective embossed area of about 10-50% and preferably
20-40% of the primary backing surface.
Generally, in the second arrangement, the greater the
number of bosses/cm2, the higher will be the peel strength of the
fleece or web on the substrate, all other factors such as fleece
or web weight on the substrate, linear pressure and temperature
of the calender rolls, and linear rate of speed of substrate in
the machine direction being held constant. Further, the main
considerations for the optimum height of bosses are the effect
of various heights on the rates of wear to bosses as is readily
understood by those skilled in the calendering art. When a
roll with a non-deformable surface such as with a chrome plated
roll is used opposite to said embossed roll there is a tendency
with decreasing heights of bosses for calendered webs to stick
to the embossed calender roll rather than readily separating
therefrom during processing. However, when a deformable roll
such as one clad with cotton-paper is used, then there is a sub-
stantial reduction in this sticking tendency to the point where
it does not interfere in processing.
The temperature of the calender rolls will in part
depend upon the specific heat and thermal conductivity of the
fleece or web, and its weight/meter , and the speed of the sub-
strate through the nip in the machine direction. If the web is
heavier, higher temperature and slower speeds are generally pre-
ferred. In general, higher temperatures tend to permit faster
rates of the substrate in the machine direction.
It is important to note however, that whereas the speed
of the needling process is greatly affected by fiber deniers
and/or web weights, the speed of the calendering process is not
substantially affected by fiber deniers and/or web weights.
Other heating methods which can be used in conjunction
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: `-"" 1093~
with pressure to achieve bonding of a web to a substrate are
infrared radiation, ultrasonic, magnetic, and dielectric heating
of appropriate coatings and/or fiber constituents.
Primary backings made by the above described methods
show excellent tuftability with a pile weight in the range 150
to 2,000 grams/meter2, and a height in the range 3 to 30 mm.
Further, the speed to form a primary backing of this invention
is in general faster, and in the situations wherein webs of fine
denier fibers are used, is substantially faster than the speed
to form an FLW primary backing.
It has been found that for a given substrate and tufted
pile loop that the tuft lock for the primary backing of this
invention is substantially greater than the tuft lock obtainable
in an FLW primary backing.
It has been found that to achieve the same cover factor
with dye-compatible fibers in a primary backing of this inven-
tion as compared to an FLW primary backing that only half of the
weight of the dye-compatible fibers in the fleece or web are
necessary.
The web is formed on said substrate by conventional
web forming means such as for example, a conventional carding
machine which can apply a unidirectional fleece or a randomly
oriented fleece by a random card as in the case of a Fehrer K 12,
or a cross-lapped web made by layering in a moving conveyor
system.
Subsequent to forming the web on the substrate, the
material is fed into a calender which is at a temperature which
largely depends upon the melting point (ASTM D 2117-64) of the
heat fusible fiber contained in said web. It will normally be
lower than about 300C and has to be closely controlled to avoid
the tendency of the web to wrap around the heated rolls. More
specifically the materials with a low softening point can be
,
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1093~50
calendered in rolls having a temperature of about 150C. The
pressure of the calender should preferably be designed to allow
for linear pressures of up to about 350 Kp/linear cm. Problems
from static electricity build up can be avoided by treating the
web with moisture during processing and/or maintaining a relative
humidity in the downstream area of about 60~.
DETAILED DESCRIPTION OF THE INVENTION
EXAMPLE 1 OF ~ METHOD FOR MAKING A
PRIMARY BACKING OF THIS INVENTION
A fleece or web having a weight of 20 g/m2 composed of
30% by weight polypropylene fiber having a denier of 3.1 dtex, a
length of 60 millimeters and having a dull finish, and 70% by
weight polyamide fiber having a denier of 3.5 dtex, a length of
60 millimeters and a dull finish was prepared in a carding line
from Hergeth which consists of a bale opener type MBL, a fore-
opener, a material transport ventilator type TV 300, a feeder-
control, a vibrachute type DS, a compact card type JK, and an
edge remover. The intrinsic viscosity with a Ubbelohde viscosi-
meter in a concentration range between 1 gram and 62.5 milli-
grams/100 ml. of solvent of the polyamide fiber determined accor-
ding to ASTM D 789 at 20C was 57 ml/g. in m-cresol, and 35 ml/g.
in 90% formic acid. The melt flow of the polypropylene deter-
mined according to a modified version of ASTM D 1238 was 13
- g/10 mins. at 190C and 2.1~ Kp of force. The fleece composed
of these fibers was conveyed to the upper nip of a three-roll
multipurpose calender (Type RKK 340 from Ramisch Kleinewefers)
where said fleece is distributed onto a woven polypropylene of
the style number 2400 sold by Patchogue Plymouth. Style 2400
is a plain weave of 24 counts/inch in the warp and 11 counts/
inch in the weft, having a weight/yard2 of 3.18. The denier of
the warp fiber is 525, and that of the weft fiber is 1050. The
upper roll of this calender is provided with an embossing
.
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~0934S0
pattern number FL 105 S sold by Ramisch Kleinewefers Kalander
GmbH, 415 Krefeld, and the middle roll is a plain steel roll.
The rolls are heated with a stream of hot oil at a regulated
pressure and in the case here the upper roll had a temperature
of 195C and the lower roll had a temperature of 130C. The com-
posite structure was embossed at a pressure of 80 daN/cm. and
processed at a speed of 14 m/min.
EXAMPLE 2 OF PEEL STRENGTH
The adhesion of the fiber fleece to the substrate
(determined according to a modified version of the test proce-
dure given by DIN 53530) gave a value of 3 N as compared to the
adhesion found for the fiber fleece in an FLW primary backing
which gave a value of close to 2 N.
The modified portion of the test is to apply an adhe-
sive tape such as sold by Beiersdorf AG, Hamburg, which is sub-
sequently rolled twice with a metal roller of 4.2 Kg having a `
width larger than the specimen. The specimen is trimmed at each
edge to give a width of 50 mm. The fleece with the adhesive
paper on top is separated from the base cloth. The base cloth ~ -~
then is clamped in the stationary jaw, and the ply consisting
of the fleece and the adhesive paper are clamped in the moving
jaw of a tensile tester described in DIN 51221. It is then ~ -
tested according to DIN 53530 with analysis according to DIN
53357.
EXAMPLE 3 CONCERNING TUFT LOCK AND TUFTABILITY
A piece of backing 10 meters long and one meter wide
prepared by the above procedure was tufted. The loop pile had
a two ply of 1260 dtex fiber made from 100% nylon 6 with a 1/4
inch pile height and 5/32 of an inch gauge and a pile weight of
about 520 g/m~. The tuftability of this product was visually
determined to be excellent by two technicians making independent
observations.
- 13 -
` ` 10934S0
Tuft lock according to a slightly modified version of
ASTM D 1335-67, i.e. using only a tufting clamp and loop hook,
but not a cylindrical specimen holder of the cut away type, was
measured for an FLW primary backing and the backing made accor-
ding to the example of a method for making a primary backing of
this invention. Each primary backing was tufted under the same
conditions with the same pile yarn as described above. A value
of 85 cN was found in the case of the tufted FLW primary backing,
and a value of 140 cN was found in the case of the tufted
primary backing of this invention.
EXAMPLE 4 OF TENACITY OF A TUFTED CARPET MADE WITH
FLW BACKING OF THIS INVENTION
Samples of primary backing of style 2400 are both made
into a primary backing by the process given in Example l of a
method for making a primary backing of this invention and needle-
bonding to form an FLW primary backing. Two different tufting
operations are subsequently employed on each. One involving 8
stitches/inch and the other 6.5 stitches/inch. The pile loops
have a gauge of 5/32 of an inch, are 2 ply of 1260 denier poly-
amide-6. The tufted carpet is subsequently dyed by a winch
dyeing process prior to a determination of tensile strength in
the warp and weft directions. Results in decanewtons, daN, are
tabulated hereinafter.
Poly Bac FLW Product of Invention
- (Reg. TM)As After As After
Direction2400Finished TuftingFinished Tufting
Warp 100 42 40* 50 46*
Weft 76 56 26* 64 29*
Warp 100 42 42** 50 48**
Weft 76 56 23** 64 27**
* Tufted with 6.5 stitches/inch.
** Tufted with 8 stitches/inch.
r
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1 0 9 3 4 ~i0
EXAMPLE 5 OF PIGMENTED POLYPROPYLENE USED
IN TllE PRIMARY BACKIN6 OF THIS INVENTION
A 70 p rts A~oco 5013 polypropylene to 1 p rt o- 35X by we~ght of
carbon blac~ ln polypropyl~ne, D 1937 sold by Hercules, ~as ~elt blende~
and extruded an~ ortented tnto ftbers hav~ng ~ denler of 3.1 dtex.
A ftb~r web of 25 parts of the above p1g~ented polypropylene to 75
parts of the ~bove unp~g~ented polypropylene f~ber each hav~ng a denter
of 3.1 dtex ~nd a length of 60 mlll~eters WQS forned on style nu~ber
2400 and fused thereto by the method disclosed under Example 1 of a
~ 10 ~ethod for ~ktng a prt~ary backtng of thts invont~on.
_ The results ~orc sat~sfactory.
EXUMPLE 6 OF A D~EABLE POLYPROPYLENE USED
IN THE PRIMURY BACKING OF THIS INVENTION
A ftber eade fro~ a co~postt10n co~prtstng 2 X by we19ht of poly-
~I,3-dt-~-plpcr1dyl) propane adlp~1de) h sed upon the ~etght of A~oco
501~ pol~propylene was used 1n the s~e manner as the ptg~ented polypro-
pylene 1n prev10us exa~ples.
The pr1rary backtng was tufted and dyed by h ~ers10n 1n an aqueous
solut10n conta1n1ng as the sole dyestuff. 0.5 we1ght percent Teras11
Blue BGL ~C.I. D1sperse Blue 73), 2 we19ht pereent wett1ng ~gent. and
sufftc1-nt for 1c ctd to re wlt 1n a pH o 5 at a 50:1 11quor rat10.
The carpet ~as placed 1n a hth at 50C. The bath was ra1sed to
the bo111ng polnt, ant held there for 1 hour. The carpet was then
r1nsed, and secur d 1n aqueous 2 percent wettlng agent for 15 ~1nutes
~t 50C.
The r~sults were sat1sf~ctory.
1 0 9 3 4~;0
EXAMPLE 7 OF PRIMARY BACKING USING
WEIGHT RATIOS OF FIBERS
. . ............. .
Prt~ry b~ck1ng for tufted carpets have been ~ade by the process
under Exa~ple 1 of a ~ethod for ~aktng pr1~ary backing of thls Inventlon
and are glven ln the follow1ng Table
~elght of Substr~te Welght of ~eb R~t10s by We1ght
9l~2 o~/sq.yd 9/e2 ozlsq yd PDlya~ide-6 Polypropylene
48 1 42 20 0 59 7 3
llO 3.2~ 20 0 59 7 3
250 7.37 20 0 59 7 3 -
600 17 70 20 0 59 7 3
llO 3 24 20 0 59 9
llO 3 2~ 20 0 59 7 3
llO 3 2~ 20 0 59 5 5
llO 3 2~ 20 0 59 3 7
110 3 24 20 0 59 l 9
llO 3.24 20 0 59 0 IO
llO 3 24 8 0 24 7 3
110 3 2~ 12 0 35 7 3
llO 3 24 16 0 47 7 3
110 3.2~ 20 0 59 7 3
1l0 3.2~ 25 0 74 7 3
110 3 2~ 30 0 89 7 3
llO 3 2~ 40 1 18 7 3
1~0 3.2~ 50 l 48 7 3
110 3 2~ 20 0 59 7 3
EXA~PLE 8 OF A PRIMARY BAC~ING PARTICULARL~
SUITABLE FOR FINE GAUGE TUFTED CARPErS
A he t fuslble ~eb of 25 gra~s/sguare ~eter is applied as dlsclosed
ln Exa~ple 1 onto both sldes of a plaln weave substrate ln two
subs H ent c-lender~ng steps The pl~in we~ve ls 26 counts per inch
1n the werp by 11 counts per 1nch in the weft The warp and weft
f1bers are both ~ult~flla~ent flbers of 500 dtex whereln each slngle
flla~ent is ~bout 5 dtex and ts round 1n cross-section and whereln
there 1s a producer's twlst of about lS turns per ~eter The web ts
co~posed of lOOt by welght of a heat fustble f1ber of polypropylene
as dtsclosed ~n Exa~ple 6 h vtng a denter of 3 1 dtex~ and a length
of 60 ~tll h eters
``: 1093450
A bond b t~e-n u ld web ~nd u 1d substr~t~ orm~d 1n the nlp o-
two count r-rot~t1ng rolls One ot ~ld two roll~ cont ct1ng the w~b
covercd s1de 1~ ~ chro~lu~ plat d ~t~lnle~s ~t~l roll at 185C, and th~
other ls a cotton-p~p~r cl-d st el roll at 25C. ~h- cotton-p per 15
75X cotton-psp r, l5X 11n n ~nd 10~ wool, l20 n~ th1ck, and has a hard-
nes~ v~lu~ o~ 70 ~hore D.
~h~ t1n1~hed prl~ary h ck1ng ~or ~1ne gaugc tu-ted carpet 1s tu-t-
abl- w1th pll- loops whlch have g~uge o~ 5/64 of an 1nch and are 1 pl~
ot 1260 d nl r poty~1de-6.
~h~ u sth t1c ~pp~r~nco ot a t1ne gsug~ tutt d c~rpet w1th ~
tl~ce l yer ot he~t tuslbl- w b bon~od thereto 1s supcr10r on two
grounds to one ad~ w1thout s~1d t1~QCO 1) there ls substant1ally
~or~ un1tono1ty to both p11e he1ght ~nd p11e denslty, ~nd 2) gr1nn1ng
problo~ ubst~nt1slly h ~ wned.
~he ~bove x-~ples ~r 1ntend~d only to clar1ty the 1nvent10n
Y~r1~t10ns on t ~r ~pp~r nt to one sk111ed 1n the art and are
1nt nd d to be w1th1n the scope ot the 1 m cnt10n
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