Mechanical surface finishing process for textile fabric

A process is provided for mechanically surface-finishing a textile fabric which comprises continuously feeding said fabric from a source of supply, such that said fabric lies in a single plane, subjecting successive adjacent sections of the fabric to intermittent mechanical impact with an abrasive means across the width of said fabric thereby avoiding substantial sustained contact between the fabric and the abrasive means, the mechanical impact being at a force and frequency sufficient to cause a substantially uniform modification of the surface characteristics of the fabric. Textile fabrics with modified surface which may be made by the above process are also provided. Apparatus for mechanically surface-finishing a textile fabric according to the aforedescribed process is further provided.

Referring now to the drawings and in particular to FIG. 1, the fabric 10 to 
be treated is unrolled from a fabric supply roll 1 under controlled 
tension and led to guide rolls 2 and 3. Guide rolls 2 and 3 may either be 
fixed or idling rolls, and they function to position the direction of the 
fabric so that its continued path will be in approximately the vertical 
direction while it maintains contact over substantially its entire width 
with the lower guide plate 4a. The path of the fabric continues over the 
upper guide plate 4b of the guide plate set and passes between fabric 
stabilizing rods 5a and 5b over fabric guide plate set 6a and 6b and to 
guide rolls 7 and 8 which function to change the direction of the fabric, 
which then moves to fabric take-up roll 9 onto which it is wound. 
Guide plate sets 4a and 4b and 6a and 6b may be adjusted in both the 
horizontal and vertical directions. The construction of guide plate sets 
4a, 4b, 6a and 6b may vary widely and may consist of plates as illustrated 
or actual channels. Between guide plates 4a and 4b and 6a and 6b the 
fabric passes between abrasive rolls 11 and 11a and corresponding flap 
rolls 12 and 12a. The abrasive rolls are covered with a suitable abrasive 
material such as sandpaper, the grit size of which may vary depending upon 
the desired effect as described more fully below. Guideplates 4a and 4b 
and 6a and 6b are adjusted to position the fabric accurately so that it 
will pass near to but not touch sanding rolls 11 and 11a unless it is 
impacted onto the sanding rolls by action of flap rolls 12 and 12a as 
described more fully below. Attached by suitable means to rolls 12 and 12a 
are flaps illustrated in FIG. 1 as 13a, 13b, 13c and 13d on roll 12 and 
flaps 13e, 13f, 13g and 13h on roll 12a. The flaps may be installed as 
illustrated by simply bolting them onto the flap roll so that when the 
rolls are at rest the plane of the flaps is essentially tangential to the 
rolls. In this embodiment, when the flap rolls are rapidly rotated, the 
centrifugal force will extend them substantially radially from the roll. 
The flaps may also be installed so that they extend radially from the flap 
roll while the roll is at rest, i.e., in the absence of centrifugal 
forces. The flaps may be made of a wide variety of suitable reinforced or 
non-reinforce materials such as neoprene rubber, urethane, polyvinyl 
chloride, nylon, or even steel and other sheet and even composites thereof 
of sufficient durability and flexibility to accomplish the desired result. 
The flap rolls may be driven by motor 14 via drive shaft 24, pulleys 15 
and 15a and 17 and 17a, belts 16 and 16a and shafts 18 and 18a. Sanding 
roll 11 and 11a may be driven by motor 19 via drive shaft 25, pulleys 20 
and 20a and 22 and 22a, belts 21 and 21a via shafts 23 and 23a. 
When in operation sanding rolls 11 and 11a rotate as do flap rolls 12 and 
12a. The distance flap rolls 12 and 12a and sanding rolls 11 and 11a 
respectively is adjusted so that in the absence of fabric 10 the flaps 
would impinge upon sanding rolls 11 and 11a to a predetermined depth of 
the flaps. When the machine is operating and threaded up with fabric 10, 
flaps 13a-h will be extended substantially radially by centrifugal force 
from the rapidly rotating rolls 12 and 12a respectively and will 
intermittently impact the fabric with considerable force onto the sanding 
rolls 11 and 11a. 
Depending upon the desired effect, the sanding rolls 11 and 11a and the 
flap rolls 12 and 12a may independently be rotated either clockwise or 
counterclockwise. Speed of rotation of both the sanding rolls and flap 
rolls may also vary widely depending upon the desired effects as described 
below. 
FIG. 2 provides a more detailed representation of a treatment station which 
comprises the sanding roll 11 and flap roll 12 with flaps 13a, 13b, 13c 
and 13d fabric guideplates 4a and 4b. In this schematic drawing the fabric 
10 is shown while being impacted by flap 13c onto the cover of the sanding 
roll 11. It should be noted that while FIG. 1 illustrates only two 
treatment stations both of which are of the same type as that illustrated 
in FIG. 2, the actual apparatus may include only one station or 
alternatively two or more stations, e.g., three, four or even more 
stations may be provided on the apparatus for treatment of one or both 
sides of the fabric. The treatment stations, furthermore, need not 
necessarily be all of the same type as illustrated in FIG. 1 but rather 
may include stations of different types, e.g., those illustrated in FIGS. 
3 and 4 discussed below, as well, even on the same apparatus. 
As mentioned, FIGS. 3, 4 and 5 illustrate alternative treatment stations 
provided with means by which the fabric may be caused to impact onto a 
rapidly moving abrasive means, although it should be appreciated that 
there may be others within the scope of the present invention. In FIG. 3 
the fabric 10 is caused to impact onto the abrasive covered roll 11 by 
means of a rapidly rotating non-circular bar, for instance as illustrated 
a square bar 30 which will alternately allow the fabric to clear the 
sanding roll and to impact it upon the roll. In this embodiment the roll 
11 may be covered with a compressible foam which is placed on the roll 
between its outer periphery and the abrasive means so that the impact of 
the fabric 10 upon the abrasive means is softened and jamming of the 
fabric between the abrasive means and the impacting means is prevented. 
Alternatively the non-circular bar 30 may be covered with a compressible 
foam for the same purpose. Also, it is particularly advantageous in the 
embodiment of the invention illustrated in FIG. 3 that the impacting means 
30 be disposed either above or below the point of closest proximity 
between the abrasive means 11 and the impacting means. Such disposition of 
the impacting means may also be advantageous in the alternative embodiment 
illustrated, for instance, in FIGS. 2, 4 and 5 as well as in other 
embodiments where the impacting means may be, for instance, an oscillating 
bar or even a rotating eccentric roll, and the like. 
FIG. 4 illustrates a further embodiment where an intermittent airstream 40 
is emitted from a nozzle 42 to cause the fabric 10 to be impacted 
intermittently upon the surface of the sanding roll 11. 
FIG. 5 illustrates yet another embodiment of the apparatus of the present 
invention. In this embodiment the fabric 10 is moved over idler roll 50 
changing its direction and then over spacing rolls 51, 52, 53, 54 and 55. 
Then the fabric is caused to move over idler roll 56 to again change the 
fabric direction. The spacing rolls are designed to prevent contact 
between the fabric 10 and the sanding surface unless impacted upon it by 
the flaps as illustrated. Thus, during operation flap rolls 62, 63, 64 and 
65 impact the fabric 10 onto the abrasive-covered surface of 11b with 
flaps 66a through d, 67a through d, 68a through d and 69a through d. 
A wide variety of fabrics may benefit from being processed according to the 
present invention. Examples of such fabrics include woven, knit, non-woven 
fabrics, as well as coated fabrics and the like. Even certain films may 
benefit from treatment according to the present invention and films made 
from polymers, paper, and even natural products in sheet form such as 
leather may be processed according to the present invention. Examples of 
knit fabrics include double knits, jerseys, tricots, warp knit fabrics, 
weft insertion fabrics, etc. Woven fabrics may be plain weaves, twills or 
other well-known constructions. Such fabrics may be constructed from spun 
or filament yarns or may be constructed by using both types of yarns in 
the same fabric. Fabrics made from natural fibers such as wool, silk, 
cotton, linen may also be treated, although the preferred fabrics are 
those made from synthetic fibers such as polyester fibers, nylon fibers, 
acrylic fibers, cellulosic fibers, acetate fibers, their mixtures with 
natural fibers and the like. Particularly significant improvement in the 
surface characteristics of fabrics has been observed on fabrics containing 
polyester fibers. 
As noted above, fabrics processed according to the present invention 
generally may be characterized as having a more uniform surface finish 
than fabrics processed according to conventional methods. The process may 
be used to provide a finish on the fabric surface which may be apparent to 
the naked eye, or a finish may be achieved which may not be apparent to 
the naked eye but which is quite apparent to the touch. The fabric may 
assume a generally softer hand and the fabric bending modulus may be 
reduced. 
Fabric such as knit texturized polyester filament fabrics may be caused to 
shrink upon being processed according to the present invention in the 
width direction resulting in a higher fabric weight. Furthermore, even if 
the fabric is stretched again to its original width and approximately its 
original weight per unit area, the fabric may generally be characterized 
as having a fuller, bulkier hand. Polyester filament fabrics may lose 
their undesirable "plastic-like" feel and the hand of such fabrics will 
become more similar to fabrics made from natural fibers such as wool or 
cotton. Products such as polyester double knit fabrics may, in certain 
instances, be characterized as having a density, uniformity and shortness 
of cover which cannot be obtained practically by means of conventional 
sanding or napping techniques. 
The process of the present invention permits finishing of fabrics which are 
generally too stretchy or too light in weight to be finished by 
conventional sanding techniques. Conventional methods rely frequently on 
tension to bring the fabric into contact with the sanding means. Where 
contact is accomplished by compressing the fabric between a backing and 
the sanding surface, tension is required to keep the fabric from being 
grabbed by the sanding roll and wrapped around it. Due to the intermittent 
nature of the contact with the sanding roll and due to the proper use of 
fabric guiding plates a considerably lower amount of tension is sufficient 
according to the process of the present invention so that it is possible 
to finish very lightweight fabric such as lightweight jersey knits. These 
lightweight jerseys in conventional finishing techniques pose very serious 
problems because they elongate very easily and neck down under tension, 
and their selvedges have a tendency to roll under tension. Also, in 
conventional sanding techniques it is almost impossible to control the 
degree and uniformity of treatment of lightweight woven fabrics while both 
results are possible according to the process of the present invention. 
It has been found that particularly good results may be achieved according 
to the process of the present invention by application of the process to a 
double knit such as that constructed from texturized polyester filament 
yarns, e.g., from 150/34 denier yarns. Ordinarily, in order to obtain an 
appealing, soft, spun-like, uniform surface finish by conventional 
sanding, fabrics of this type must be constructed from more expensive 
yarns, for example 150/50 denier or even 150/68 denier yarns. Fabrics 
constructed from 150/34 denier yarns, however, generally provide a choppy, 
coarse-feeling, non-uniform surface finish when sanded conventionally. It 
has been found, however, surprisingly that fabrics made from such 150/34 
denier texturized polyester yarns may be subjected to the process of the 
present invention to obtain a spun-type finish on the fabric that is 
approximately equivalent in hand and appearance to the finish obtained by 
conventional sanding of more expensive fabrics constructed from, for 
instance, 150/50 denier texturized polyester filament yarns. Because a 
heavier fabric generally must be constructed from, for instance, 150/50 
denier filament yarn in order to maintain fabric crispness, the ability to 
use a fabric constructed from 150/34 filament texturized polyester yarns 
yielding an equivalent finish also permits the use of a lesser weight 
fabric. 
The process of the present invention is not limited, however, to textile 
materials per se and, for instance, application of the process to clear 
films may result in a matte-type finish providing a translucent film. 
Application of the process to paper of sufficient strength to undergo 
treatment may result in a softening of the surface of the paper. 
According to the process of the present invention, successive adjacent 
sections of the fabric are intermittently impacted upon an abrasive means 
across the entire width of the fabric. The fabric is ordinarily extended 
to its open width and may be moved in the warp or longitudinal direction. 
Sustained substantial contact between the fabric and the abrasive means is 
avoided, the mechanical impact being of a force and frequency sufficient 
to cause a substantially uniform modification of the surface 
characteristics of the fabric. As will be apparent to those skilled in the 
art, the extent of modification of the surface characteristics, the 
specific effects obtained, and the rate at which these effects may be 
obtained will depend upon the operating conditions of the machine used in 
the process and the nature of the fabric being treated. Operating 
parameters of the apparatus used in the process, e.g., force and frequency 
of impact, grit size of abrasive means and other variables, may be 
adjusted over a broad range. For instance, the linear speed of the fabric 
relative to the sanding means may vary from about 1 yard to about 200 
yards per minute and will preferably be between about 5 and about 100 
yards per minute, depending upon the number of treatment stations 
available, the type of fabric and intensity and character of the treatment 
desired. 
The abrasive means employed in the process and in the apparatus of the 
present invention may include any of a wide variety of abrasive mechanisms 
which function to provide the desired results in the product material. 
Typically, as illustrated in FIG. 1, the abrasive means may be a drum 
which has been covered with sandpaper or sanding cloth. It has been found 
that using such abrasive means as a drum covered with sanding paper or 
sanding cloth according to the teachings of the present invention will 
provide an apparatus and method whereby many results obtainable by other 
sanding methods and obtainable by napping as well as results not 
obtainable by either napping or conventional sanding techniques may be 
achieved. 
It should be understood, however, that the invention is not limited to 
drums covered by sandpaper or sanding cloth as the abrasive means, but may 
include other suitable abrasive means. One particular embodiment which has 
been envisioned is particularly suitable where all results obtainable by 
napping may be achieved. According to such embodiment the drum instead of 
being covered by sandpaper or sanding cloth is covered with uniformly 
spaced napping wires. Thus, the surface of the material to be treated 
would be impacted by the impacting means in a similar fashion as 
illustrated in the figure onto a drum covered with such napping wires. 
Typically the wires will be rather fine, flexible or flexibly embedded 
napping wires. 
It may also be advantageous to embed the napping wire in a support 
substrate so that the wire tips protrude very little or barely from the 
support substrate. The substrate may be of controlled compressibility such 
as foam rubber, soft rubber, felt and the like. In this manner the 
compressible embedding medium will be compressed during impact. This in 
turn will determine the extent to which the wire tips will protrude from 
the surface of the embedding medium which will determine how far the 
napping wire tips can penetrate into the fabric surface. By means of such 
technique the character and intensity of the effect achieved may be more 
precisely controlled. Also, the substrate may assist in releasing the 
fabric after impact from the napping wires and so help to prevent or 
minimize the tendency of the fabric to wrap around the napping roll. 
Where the abrasive means is a sanding paper, the grit of the sanding paper 
may vary widely, with grit sizes of about 16 to about 600, preferably 
between about 80 and about 400, e.g., about 180 to about 320 being 
appropriate. On machines with multiple treatment stations different size 
grits may be employed for the different sanding rolls in different 
sequences to accomplish specific effects. For example, it has been found 
desirable to pretreat the fabric at a first sanding station with a fairly 
coarse grit in order to make the fabric surface more easily alterable by 
the subsequent finer grits at subsequent treatment stations. 
The use of finer grit sanding paper will be particularly recommended for 
lightweight fabrics made from fine denier fibers or filaments, and will 
also be recommended for other fabrics, if a particularly subtle and fine 
finish is desired and when it is desired that the effects of the treatment 
be confined primarily to the fabric surface. The relative intensity of the 
treatment accomplished by means of the present invention is dependent not 
only upon the grit of the abrasive means but also on the force of the 
impact of the fabric on the abrasive means. This is in turn a function of 
the radius of the flap roll, flap length, bending modulus of the flaps, 
specific gravity or density of the flaps and the extent to which the flap 
front edge does not clear the surface of the opposing sanding roll and 
speed of rotation of the flap roll. 
In general it has been observed that a significant effect may be obtained 
according to the process of the present invention with a finer grit 
sandpaper than that used in standard sanding because the cutting edges of 
the grit are impacted upon the fibers of the fabric with considerable 
force causing most if not all of the sanding grains to cut into or abrade 
the surface of the textile material. Since a significant effect is 
obtained with a finer grit and since simultaneously more cutting grains of 
a finer grit are located on the surface of the sandpaper per unit area it 
is thought that the number of fibers affected per unit surface area is 
consequently significantly greater than, and perhaps several times, that 
obtained with the coarser grit material in a normal sanding operation so 
that the finish which results is more uniform, fine and dense. Thus, 
frequently fabrics treated according to the process of the present 
invention may not require shearing since the individual fiber ends which 
are formed are generally very short and uniform in length which also 
distinguishes the products of the present invention from those of 
conventional sanding techniques. 
The surface speed of the sanding means relative to the fabric may vary 
widely and may be between about 10 feet per minute and about 8,000 feet 
per minute, preferably between about 500 feet per minute and 2,500 feet 
per minute. As discussed above in connection with the apparatus, the 
sanding roll may be rotated clockwise or counterclockwise and the 
direction of rotation of the flap rolls may either correspond to that of 
the sanding roll or may be opposite thereto. For instance, where the 
sanding roll and the flap rolls are both rotated in a clockwise direction 
very lightweight, stretchy fabric may have less tendency to be grabbed by 
the sanding roll and to wrap around it. 
The force at which the fabric is caused to impact upon the abrasive means 
is a function of the speed of rotation of the flap roll, the length and 
stiffness of the flaps, the diameter of the flap roll, as well as the 
density of the flap material, and other variables, but generally the flap 
roll will rotate at speeds from about 100 to about 8,000 rps's, preferably 
from about 500 to about 6,000, e.g., about 1,000 to about 4,000 rpm's. 
Fabrics which have been processed pursuant to the present invention may be 
subjected to various subsequent treatment operations. It has been found, 
for instance, that a particularly appropriate post treatment for the 
products of the present invention may be brushing. Thus, fabrics may be 
mechanically surface finished according to the invention using 
comparatively mild treatment conditions, e.g., a relatively fine grit 
sandpaper as the abrasive means, or a relatively low impact force of the 
fabric onto the abrasive means, or a comparatively lower frequency of 
impact so that the strength of the fabric is reduced less than it might 
otherwise be. Then by brushing the fabric vigorously using, for example, 
nylon or metal brushes, such as brass or steel brushes, modification of 
the surface characteristics of the fabric may be desirably enhanced. 
I have illustrated and described what I consider to be the preferred 
embodiments of my invention. It will be apparent, however, that various 
modifications may be resorted to without departing from the broader scope 
of the invention as defined by the claims. 
EXAMPLE 1 
A doubleknit fabric was prepared from 1/150/50 Monsanto type 446 100 
percent texturized polyester filament yarn. The fabric was scoured, 
jet-dyed to a light blue color, slit and then heat set to provide a 
control sample. The finished weight was between 133/4 and 141/4 ounces per 
yard, with a width of between 60 and 62 inches. The Mullen Burst Strength 
(ASTM No. D-231 (1975)) was 275 lbs. FIGS. 6 and 7 are scanning electron 
photomicrographs (SEPM) taken of the fabric at 100.times. and 350.times. 
respectively. 
A separate sample of the above yarn was knitted and the resulting 
doubleknit was then processed by scouring, jet-dyeing to a light blue 
color and slitting. After slitting, but prior to heat setting the fabric 
was mechanically surface treated according to the process of the present 
invention to provide a product of the present invention. SEPMs of the 
sample are provided in FIGS. 8 and 9 at 100.times. and 350.times.. The 
processing parameters are set forth below in the Table. After treatment, 
the Mullen Burst value was 235 lbs. 
Another sample of the above fabric was treated in substantially the same 
manner as set forth above for the sample according to the invention, 
although it was colored navy blue and instead of mechanically surface 
finishing prior to heat setting according to the present invention it was 
Gessner sanded. The Mullen Burst value for the Gessner-sanded product 
after treatment was 230 lbs. SEPMs of the Gessner-sanded product are set 
forth below in FIGS. 10 and 11 at 100.times. and 350.times.. 
Observation of the fabric treated according to the present invention 
revealed that it had a very luxurious, warm and soft surface hand and a 
very short, dense cover. The cover was readily apparent to the naked eye 
although because of its relative shortness it permitted the construction 
of the fabric to be fully visible. The control fabric, that is the fabric 
that has had no mechanical surface finishing, by contrast had a clear 
surface, no cover, and had the typical hard, "plastic", somewhat slick 
appearance and hand of texturized polyester doubleknits. The appearance 
and hand of the sample treated according to the present invention was 
comparable to that of a fabric prepared from fine wool yarns. The sample 
which was conventionally surface finished by means of a Gessner sander did 
not approach the desirable characteristics of the sample treated according 
to the present invention, especially with regard to softness of hand, 
density of cover, and similarity to a fabric made of fine wool yarns. 
Reference to the SEPM of the control sample, the sample treated according 
to the present invention, and the conventionally sanded sample at 
magnifications of 100.times. and 350.times. shows that the fibers of the 
fabric of the present invention are broken to some extent but are 
predominately extensively modified by the formation of lamella shaped 
protrusions on the fiber surfaces and by the formation of scar type 
surface modifications on the fiber surfaces. The Gessner-sanded samples by 
contrast show a substantial number of cut and broken fibers with only very 
minor modification of the surface characteristics of the individual 
fibers. 
EXAMPLE 2 
Example 1 was repeated using a 1/150/34 100 percent texturized polyester 
filament yarn. A control (untreated) sample, Gessner-sanded sample and a 
sample treated according to the invention were prepared. In this example 
the Gessner-sanded sample exhibited no significant difference from the 
untreated control sample, and the product in fact did not have a 
commercially acceptable finish due to the relatively coarse nature of the 
150/34 texturized polyester yarns from which it was made. This same fabric 
which was treated according to the present invention, however, had a 
significantly improved surface feel and a warm, pleasant wool-like hand as 
compared to the control sample. In fact, the sample compares very 
favorably to the Gessner-sanded version made according to Example 1 from 
the more expensive 150/50 texturized polyester filament yarns. The Mullen 
Burst value for the untreated control was 285 lbs. as compared to 220 lbs. 
after Gessner-sanding and 240 lbs. after surface finishing according to 
the present invention. Thus, while the surface modification is significant 
according to the process of the present invention, less strength loss is 
observed compared to Gessner-sanding. 
EXAMPLE 3 
The fabric used in this Example was a yarn-dyed, polyester doubleknit. The 
yarn used was a 1/150/34 texturized 100 percent polyester filament yarn. 
The control sample was prepared by sponging, slitting and drycleaning the 
knitted fabric. The finished weight was 12.4 ounces per yard, with a width 
of 64 inches, and a Mullen Burst strength of 215 lbs. The sample of the 
present invention was then processed as set forth in the Table. The Mullen 
Burst value was 120 lbs. After surface finishing the fabric was heat set, 
sheared, heat set again and decated. The finished weight was 11.6 ounces 
per yard, with a width of 60 inches. 
A sample of the same cloth was then processed in the same manner as 
described above except that instead of mechanical surface treating 
according to the present invention the fabric was napped after the first 
heat setting operation, and then sheared, heat set again and decated. The 
finished weight was 11.70 ounces per yard with a width of 591/4 inches. 
The fabric treated according to the process of the invention had a very 
soft, cotton-like surface hand as compared to the typical hard, slick, 
"plastic" and unappealing hand of the untreated control sample. Because of 
the relative shortness of the cover on the fabric treated according to the 
invention the clarity of the pattern of the fabric was not obscured to any 
measurable extent except for a very minor reduction of color contrast. The 
fabric construction, however, was still discernable. The napped fabric 
made from the same control fabric had a much harsher, drier somewhat 
wool-like hand. Both the color pattern on the surface and the construction 
features of the fabric were extensively obscured by napping. FIGS. 12, 13 
and 14 are SEPMs at 35.times., 100.times. and 350.times. of the control 
sample. FIGS. 15, 16 and 17 are SEPMs at 35.times., 100.times. and 
350.times. of the doubleknit yarn dyed product which has been treated 
according to the process of the present invention. FIGS. 18, 19 and 20 
show SEPMs at 35.times., 100.times. and 350.times. respectively of the 
napped samples. Comparison of the SEPMs reveals that the fibers at or near 
the surface of the sample which has been treated according to the process 
of the invention are relatively severely modified with the formation of 
lamella-type protrusions and scars as well as by a very small amount of 
cut fibers. The napped samples by contrast show very little or no actual 
fiber surface modification although there are a substantial number of cut 
fibers. Visual observation reveals that the napped sample has a random 
layer of disoriented fibers established on the surface forming a 
substantially flat cover on the fabric. The yarn structure has been 
substantially disturbed, and the original construction is largely 
obscurbed. On the sample treated according to the process of the present 
invention, by contrast, the original yarn structure is substantially 
intact and very few randomly oriented fibers are observed on the surface 
of the fabric. 
EXAMPLE 4 
The characteristics of 100 percent acrylic doubleknit were compared before 
surface finishing according to the present invention and after such 
finishing. The processing conditions for the mechanical surface finishing 
according to the invention are set forth in the Table. 
It was found that the sample which was treated according to the invention 
had a more natural, wool-like feel and a soft surface hand, while the 
control sample by comparison had a somewhat plastic-like hand typical of 
synthetic fabrics, although the plastic-like appearance was somewhat less 
apparent than would be the case for fabrics made from polyester fibers. 
Examination of the SEPMs of the fabric according to the present invention 
shown in FIGS. 21 and 22 at 100.times. and 350.times. respectively show 
the formation again of lamella-type protrusions on the fiber surface as 
well as scarring of the fiber surface. Comparison to the control samples 
shown in FIGS. 23 and 24 again at 100.times. and 350.times. show no 
similar characteristics. 
EXAMPLE 5 
The characteristics obtainable by the process of the invention applied to 
100 percent polyester woven fabrics made from a filament warp yarn and a 
spun filling yarn were compared. The starting fabric was woven from a 
2/150/34 Danbury-242T Dacron polyester filament warp yarn (lot number 
841). The filling yarn was a spun 12/1 T-350 Trevira polyester yarn. 
The control sample was prepared by Mezzera treatment, jet-dyeing with a 
navy blue dye, and finished by heat setting, shearing, and decating. The 
finished width was 59.4 inches (inside selvedges) with a weight of 11.5 
ounces per yard. The strength as measured by the Scott Grab Tensile test 
(ASTM number D-1682, (1975) was 263 lbs. for the warp and 156 lbs. for the 
fill. 
The above processing sequence for the control sample was modified by 
surface treatment according to the present invention prior to Mezzera 
treatment with the remaining steps in the process being identical to those 
set forth above for the control sample. The finished weight and width were 
the same as for the control sample. The mechanical surface treatment 
conditions are set forth in the Table below. After treatment the Scott 
Grab Tensile (SGT) value was for the warp 205 lbs. and for the fill 47 
lbs. 
The above procedure was repeated except that the mechanical surface 
treatment according to the invention was performed after Mezzera treatment 
and prior to jet-dyeing with the other processing steps being in the same 
order. The finished weight and width were the same. SGT strength for the 
warp was 246 lbs. and for the fill was 75 lbs. 
The above process was repeated again except that the mechanical surface 
treatment according to the invention was performed after jet-dyeing and 
prior to heat setting with the other processing steps remaining the same. 
The finished weight and fabric width were again the same. 
The latter procedure was followed again except that instead of mechanical 
surface treatment according to the present invention prior to heat setting 
and after dyeing, the fabric sample was Gessner sanded at this stage in 
the process. The finished weight and width were the same. The SGT value 
was 259 lbs. for the warp and 93 lbs. for the fill. 
The above procedure was repeated again except that napping was performed on 
the fabric after jet-dyeing but prior to heat setting. The finished weight 
and width of the fabric were the same. The SGT value was 264 lbs. for the 
warp and 147 lbs. for the fill. 
Examination of the samples which were processed according to the invention 
before dyeing revealed that a wool-like hand was achieved. Mechanical 
surface treatment according to the invention after dyeing of the fabric 
resulted in a fabric having a cotton-like hand. 
Thus, it can be seen that appropriate variation of the processing steps can 
be used to achieve two distinctly different products from the same 
starting material. 
Depending upon the processing sequence the samples treated according to the 
invention generally had a very attractive, soft and pleasant wool or 
cotton-like hand, while the fabric which did not have any surface 
treatment had the customary hard, harsh feel of polyester fabric. Sanding 
by conventional means, namely with a Gessner sander, resulted in only 
minor modification of the hand of the control sample, although the result 
did not approach either the softness or luxuriousness of the surface feel 
obtained by the present invention. The sample which was napped resulted in 
a relatively soft surface hand as compared to conventional sanding, but it 
did not produce either a pleasant or a soft surface finish as was achieved 
according to the present invention, especially where the surface treatment 
was performed prior to dyeing. Also, it was noteworthy that napping 
resulted in a considerably less uniform and longer cover with a great deal 
of "wild hair" protruding from the fabric surface. Even after shearing the 
finish obtained by the present invention was both more uniform and more 
attractive than the finish obtained according to the conventional 
techniques. 
FIGS. 25 and 26 are SEPMs of the control samples at 100.times. and 
350.times. respectively. FIGS. 27 and 28 are the Gessner-sanded samples at 
100.times. and 350.times., and FIGS. 29 and 30 are the samples which were 
napped, again depicted at 100.times. and 350.times.. FIGS. 31 and 32 are 
the samples which were finished according to the present invention by 
mechanical surface treatment after dyeing but prior to shearing and 
decating. Examination of SEPMs of the samples mechanically surface 
finished prior to Mezzera treatment and those treated after Mezzera 
treatment but prior to dyeing appeared almost identical to FIGS. 31 and 32 
and, therefore, need not be shown. As the SEPMs reveal, the fabric samples 
treated according to the invention, whether prior to dyeing or after 
dyeing, all showed substantial lamella protrusions from the surface of the 
fabric as well as a substantial amount of scarring. Plastic deformation of 
the fibers was also evident. Conventional Gessner sanding resulted by 
contrast in only a limited amount of fiber surface modification with 
little or no lamella formation and no plastic deformation of the fibers. 
Napping resulted in even less fiber surface modification, no plastic 
deformation of the polymeric fibers although a significant amount of fiber 
cutting is apparent. 
EXAMPLE 6. 
A jersey knit was mechanically surface finished according to the present 
invention and compared with a non-finished control sample. The control was 
prepared from 100 percent Dacron polyester T-56 1/70/34 yarns. The sample 
was processed by Mezzera treatment, jet-dyeing a light green color, 
slitting and heat setting. The finished weight was 5.75 ounces per yard 
with a width of 63 inches. The Mullen Burst strength was 130 lbs. 
Next, the above process was modified by treatment of the fabric after heat 
setting according to the invention. The process and conditions were as set 
forth in the Table. The Mullen Burst strength after treatment was 123 lbs. 
Observation of the finished samples reveals that the sample treated 
according to the present invention had a soft, warm, and luxurious hand; 
while the untreated control had a relatively slick surface hand typical of 
polyester fabrics. The sample treated according to the invention may be 
said to have a hand that is comparable to that of fabrics made from spun 
yarns. 
EXAMPLE 7 
Samples of 65/35 polyester cotton blends were treated according to the 
present invention and then compared to control samples. The warp and fill 
yarns were both 65 percent polyester, 35 percent cotton. The control 
sample was prepared by singeing and mercerizing the fabric. The finished 
weight was 4.86 ounces per square yard and the finished width was 60.3 
inches. A separate sample of the fabric was processed in the same manner 
as the control sample but was subsequently finished by treating according 
to the process of the invention. The treating conditions are set forth in 
the Table. For comparison purposes another sample was treated as above by 
singeing, mercerizing and then Gessner sanding, followed by range dyeing, 
finishing and sanforizing of the cloth. 
A visual comparison of the control sample with the sample treated according 
to the present invention showed that the sample of the invention had a 
substantially softer and more pleasing, cotton-like surface hand than the 
control without any significant loss in fabric crispness. By comparison 
sanding of the same style fabric by conventional sanding provided very 
little beneficial effect on the fabric in terms of its hand, or other 
characteristics. 
FIGS. 33 and 34 are SEPMs of the control sample at 100.times. and 
350.times.. FIGS. 35 and 36 are SEPMs of the sample which was processed 
according to the invention, also at 100.times. and 350.times.. FIGS. 37 
and 38 are SEPMs at 100.times. and 350.times. of the Gessner-sanded 
sample. Examination of the SEPMs revealed that the sample which was 
treated according to the process of the invention has lamella-type 
protrusions on the fibers at or near the surface of the fabric. There were 
also a few cut fibers, scarring and significant thermoplastic deformation 
of the polyester fibers. It was also evident that the yarns immediately at 
the surface of the fabric were flattened, apparently in conjunction with 
thermoplastic deformation of the polyester fibers. Observation of the 
SEPMs of the Gessner sanded samples revealed that the process resulted in 
very little modification of the surface fibers although certain randomly 
oriented fibers and some cut fibers were present on the fabric surface. 
EXAMPLE 8. 
A sample of woven 80/20 polyester cotton having a spun warp and a filament 
fill yarn was treated according to the process of the invention and 
compared with a control sample. The warp yarn was a 65 percent polyester, 
35 percent cotton yarn. The fill yarn was a texturized 100 percent 
polyester filament yarn. 
The control sample was prepared by the steps of heat setting, singeing and 
mercerizing. The finished weight was 4.94 ounces per square yard and the 
finished width was 60.2 inches. SGT strength of the warp was 133 lbs. and 
131 lbs. for the fill. 
A sample of the above fabric processed in the identical manner was finished 
by mechanical surface treatment according to the process of the invention. 
The finished weight and width were both the same as for the control 
sample. The processing conditions are set forth in the attached Table. The 
resulting SGT strength was 122 lbs. for the warp and 101 lbs. for the 
fill. 
A similar fabric having a spun warp yarn of 65 percent polyester and 35 
percent cotton and a fill yarn of texturized 100 percent polyester 
filament yarn was processed by heat setting, steam treating, mercerizing, 
and range dyeing to provide a tan fabric. The fabric was then 
conventionally Gessner sanded, finished and sanforized. The finished 
weight was 5.35 ounces per square yard, and the finished width was 60.5 
inches. The SGT strength for the warp was 207 lbs. and for the fill was 
181 lbs. The tensile strength characteristics of the fabric prior to treat 
ment were unavailable. 
Visual comparison of the sample treated according to the present invention 
with the control sample showed that while the surface appearance of the 
fabric was not significantly changed, the surface feel of the fabric 
treated according to the present invention was substantially softened as 
compared to the rather hard surface feel of the untreated control sample. 
The fabric crispness of the treated samples as compared to the control 
sample was substantially retained. By contrast, little or no advantageous 
modification was observed when a similar fabric was subjected to Gessner 
sanding. 
FIGS. 39 and 40 are SEPMs of the control sample at 100.times. and 
350.times. FIGS. 41 and 42 are SEPMs taken at 100.times. and 350.times. of 
a sample which has been prepared in the same manner as the control sample 
and then mechanically surface finished according to the invention. FIGS. 
43 and 44 are SEPMs of the sample which has been Gessner sanded and 
prepared as described above. Examination of the SEPMs shows that very few 
of the fibers are cut in the sample processed according to the present 
invention. Rather, the surface of the fibers has been significantly 
modified in the process. Some lamella-type protrusions are produced and 
scarring was particularly obvious. Some plastic deformation of the 
polyester fibers was observed. Also, a flattening of the yarn surfaces was 
again observed. With regard to the Gessner-sanded sample, except for some 
cutting of the fibers there was little apparent effect on the fibers of 
the fabric. 
EXAMPLE 9 
An 80/20 polyester/cotton blend fabric was treated according to the process 
of the invention using the processing conditions set forth in the Table 
before range dyeing. After range dyeing it was observed that some of the 
advantageous characteristics of the fabric treated according to the 
process of the invention were apparently lost. This sample, however, was 
subsequently brushed with either a nylon brush or a steel brush, and it 
was observed that the original beneficial effects were re-established and 
actually significantly enhanced, without any substantial strength loss. In 
fact, it was determined that even where the sample was mechanically 
surface finished according to the invention after dyeing that the 
advantageous effect of brushing with either a nylon or a steel brush 
resulted in a significant enhancement of the beneficial effects of the 
mechanical surface treatment in terms of both fabric surface softness, 
pleasantness and luxuriousness of feel, again without any substantial 
strength loss. A similar sample which was not mechanically surface 
finished according to the invention was simply brushed after dyeing with a 
nylon brush and a separate sample was brushed with a steel brush under 
equivalent conditions and practically no beneficial effect on the samples 
was observed. 
EXAMPLE 10 
A 100 percent filament embossed woven polyester napery fabric was treated 
according to the process of the invention, and its characteristics were 
compared to that of an untreated control sample. The sample treated 
according to the invention had a pleasing appearance resembling that of 
genuine cotton jacquard damask fabric and even the depressed embossed 
areas of the fabric were beneficially affected. By contrast, the untreated 
control sample had a glass-like sheen and a plastic appearance quite 
dissimilar to the subtle and fine appearance of the high priced jacquard 
woven damask fabric. 
EXAMPLE 11 
A control sample of woven 100 percent polyester filament warp and fill 
napery fabric was prepared and its characteristics were compared to that 
of a similar sample which was treated according to the process of the 
invention. It was observed that in addition to the improved surface hand 
characteristics, tablecloths or napkins made from the above-described 
material and processed according to the invention could be stacked without 
the piles of stacked fabric sliding and falling down. The overall 
appearance of the fabric was, however, changed very little and the fabric 
had a completely clear face. However, the fabric in effect did have a very 
advantageous cotton-like hand. 
EXAMPLE 12 
This Example illustrates application of the process of the invention to a 
100 percent nylon nonwoven point-bonded fabric. A control sample was 
prepared and a separate sample was subsequently processed according to the 
invention. The processing conditions are set forth in the Table. The 
nonwoven nylon fabric when treated according to the process of the 
invention exhibited a dramatically softer, kinder surface hand than the 
slick, "glassy" starting material. A dense, somewhat longer cover was 
created giving the surface of the fabric the touch and surface feel of 
material made from natural fibers. Little strength loss was encountered 
due to the treatment of the fabric. Comparison of the SEPMs of the sample 
treated according to the process of the invention shown in FIGS. 45 and 46 
at 100.times. and 350.times. respectively to the control samples as shown 
in FIGS. 47 and 48 at 100.times. and 350.times. respectively shows that 
there has been a significant generation of lamella-type protrusions on the 
fiber surface, fiber surface scarring, and visual observation revealed cut 
fibers. 
EXAMPLE 13 
A control fabric was prepared of a napped substrate fabric containing on 
its surface a coagulation type coating. A separate sample of the fabric 
was processed according to the invention using the processing conditions 
set forth in the Table. 
Observation of the fabric revealed that the original control fabric had a 
soft but tacky surface hand while the fabric which was treated according 
to the process of the invention had an even, softer but a totally 
non-tacky surface hand. The appearance of the sample treated according to 
the invention was also somewhat smoother and more uniform than that of the 
original sample. Reference to the SEPMs shown in FIG. 49 at 350.times. 
shows that there had been a gross accumulation of coagulated polymer 
present on the surface of the untreated control sample. By contrast the 
sample which has been treated according to the process of the invention 
shown in FIG. 50 at 350.times. reveals that while desirable small islands 
of the polymer coating are still present, gross accumulations have been 
substantially removed or broken up. Furthermore, the sample treated 
according to the invention also exhibits the typical lamella-type 
protrusions and scarring of the fiber surfaces. 
EXAMPLE 14 
Mechanical surface treatment according to the present invention was 
performed on a polyethylene sheet material of 2 mils thickness. The 
processing conditions are set forth in the attached table. 
Observation of the sheet material which has been mechanically surface 
finished revealed that the treatment resulted in converting a 
substantially transparent film material (the control sample) into a 
translucent film material with a milky, non-slick surface. SEPMs shown in 
FIGS. 51 (the control) and 52 (the treated sample) reveal that the treated 
sample exhibited scratches, striations, lamella-type protrusions and 
substantial plastic deformation of the surface. Quite similar effects were 
observed when a nylon film was mechanically surface finished and compared 
to an untreated nylon film. Substantially the same results were also 
observed when a polyester film sample was subjected to mechanical surface 
treatment according to the present invention. 
EXAMPLE 15 
In this Example, a heavy duty paper (white, light cardboard-type) was 
subjected to mechanical surface treatment according to the present 
invention. The paper had a thickness of 11 to 12 mils. Observation of the 
product after treatment revealed that mechanical surface treatment of the 
paper resulted in a mat, non-slick surface as compared to the untreated 
control sample. 
3 TABLE 
Fabric Processing Parameters The Flap Roll Fabric Conditions The 
Abrasive Roll Flap Tip Impact Flap Com- Impinge- Example Speed 
Tension* Passes Passes Speed Direc- Grit Speed Gap*** frequency Direc- p 
osition ment**** Treatment No. Yd./min. lbs. Face Back RPM'S ft./min. 
tion** Size RPM'S ft./min. in. min. tion** width in. in. Stations 
1,2 5 22 3 1 1800 1414 Rev. 240 2380 5608 1/8 19040 Fwd. Red Neoprene 
1/8 2 Rubber 1/16" 3 5 22 5 1 1800 1414 Rev. 240 2380 5608 
1/4 19040 Fwd. Red Neoprene 1/8 2 Rubber 1/16" 4 5 22 1 1 
1250 982 Rev. 240 1710 4029 3/8 6840 Fwd. Black Rubber 1/8 2 
1/16" 5 20 22 1 1 1800 1414 Rev. 240 2380 5608 1/8 19040 Fwd. Red 
Neoprene 1/4 2 Rubber 1/16" 6 1.33 5 1 1 1210 1267 Fwd. 
240 1720 3152 1/8 6880 Fwd. Black Rubber 1/8 1 1/16" 7,8 
10 22 1 1 1800 1414 Fwd. 240 2380 5608 1/8 19040 Rev. Red Neoprene 1/8 1 
Rubber 1/16" 9 35 22 1 1 1800 1414 Rev. 240 2380 5608 1/8 
19040 Fwd. Red Neoprene 1/4 2 Rubber 1/16" 10 1.33 11 2 1 
1210 1267 Fwd. 320 1720 3152 1/8 6880 Fwd. Black Rubber 1/8 1 
1/16" 11 5 22 1 1 1250 982 Rev. 240 1710 4029 3/8 6840 Fwd. Red 
Neoprene 1/8 1 Rubber 1/16" 12 10 22 2 1 1800 1414 Fwd. 
240 2380 5608 1/8 19040 Rev. Red Neoprene 1/4 1 Rubber 
1/16" 13 5 22 2 0 1250 982 Rev. 240 1710 4029 3/8 6840 Fwd. Black 
Rubber 1/8 2 1/16" 14 5 11 1 0 800 838 Fwd. 240 1710 
3134 1/8 
*Total tension based on entire fabric 
**Fwd. means that the roll is rotated in the same direction as the fabric 
movement; Rev. means that the roll is rotated against the direction of 
fabric movement. 
***Refers to gap or distance between fabric in its normal position and th 
abrasive roll when the fabric is not being impacted. 
****Theoretical flap penetration onto abrasive roll when fabric is not 
present.