US3120449A

US3120449A - Fibrous materials and methods of making the same

Info

Publication number: US3120449A
Application number: US100998A
Authority: US
Inventors: Hector W Griswold
Original assignee: Johnson and Johnson
Current assignee: Johnson and Johnson
Priority date: 1961-04-05
Filing date: 1961-04-05
Publication date: 1964-02-04
Anticipated expiration: 1981-02-04
Also published as: NL276182A

Description

Feb. 4, 1964 H. w. GRISWOLD FIBROUS MATERIALS AND METHODS OF MAKING THE SAME s Sheets-Sheebl Filed April 5, 1961 Twillp f Rf Y w 5 p mm m H. W. GRISWOLD Feb. '4, 1964 FIBROUS MATERIALS AND METHODS OF MAKING THE SAME 3 Sheets-Sheet 2 Filed April 5, 1961 INVENTOR A-cra/P #(ff/I/Vdl) BY dhm 7 W1 ATTORNEY Feb. 4, 1964 H. w. GRISWOLD 3,120,449

FIBRQUS MATERIALS AND METHODS OF MAKING THE SAME Filed April 5, 1961 3 Sheets-Sheet s ATTORNEY United States Patent 3,120,449 FIBROUS MATERIALS AND METHODS OF MAKING THE SAME Hector W. Griswold, Princeton, N.J., assignor, by mesne assignments, to Johnson & Johnson, New Brunswick,

NJ., a corporation of New Jersey Filed Apr. 5, 1961, Ser. No. 100,998 12 Claims. (Cl. 117-38) The present invention relates to absorbent, bonded nonwoven fabrics and to methods of making the same. More particularly, the present invention is concerned with absorbent, bonded nonwoven fabrics suitable for cleaning and wiping purposes and to methods of bonding the same whereby their absorbent properties are improved over prior art bonded nonwoven fabrics.

Absorbent bonded nonwoven fabrics have been used hitherto as wiping and cleaning cloths and have been found generally satisfactory and commercially acceptable in industry. However, in general, there is always a desire to improve the properties of such products and, in this particular case, there has been a desire to improve the liquid absorbency and capacity properties while desoreasing the liquid strike-through characteristics.

It is therefore an object of the present invention to improve presently available bonded non-woven fabrics whereby they possess improved liquid absorbency and capacity properties along with decreased liquid strike through characteristics.

It has been discovered that such an object may be accomplished by employing improved methods for bonding such nonwoven fabrics which comprise: applying to one side of a fibrous layer of overlapping, intersecting fibers a binder in a print pattern covering from about 5 percent to about 35 precent of the surface of that side of the fibrous layer; and applying to the other side of the fibrous layer a binder in a print pattern also covering from about 5 percent to about 35 percent of the surface of the fibrous layer. The physical or geometric relationship of the two opposed binder print patterns applied to the opposite sides of the fibrous layer, however, is such that the respective binder materials, as they penetrate inwardly from the surface of the fibrous layer either do not meet at all in the center of the fibrous layer or, if they happen to meet, do not have a common binder contact area of more than about 5 percent of the total surface area of the fibrous layer.

If this principle is followed, then the surfaces of both sides of the bonded nonwoven fabric are found to be well adhered, resistant to linting, and durable, whereas the central portion has a relatively low density or low compactness, is soft and relatively unbonded and the nonwoven fabric, as a whole, possesses good liquid absorbency and good liquid capacity and low strike-through properties.

The fibrous webs which will be used to illustrate the present invention are card webs and the resulting bonded nonwoven fabrics are in the general type of Masslinn nonwoven fabrics described in patents referred to hereinafter. Other types of nonwoven fabrics are, of course, applicable to the principles of the present invention. Such other types of nonwoven fabrics include, for example, cross-laid card Webs; the isotropic nonwoven fabrics, as described in U.S. Patents 2,676,363 and 2,676,364; as well as the Keybak rearranged nonwoven fabrics, as described in US. Patent 2,862,251.

Although the present invention will be described in greater particularity with reference to fibrous webs made of natural and synthetic or man-made cellulosic fibers, such as cotton and rayon, which are preferred because of their hydrophilicity and water absorbency, other natural, manmade and synthetic fibers may be used either by themselves or in blends of various proportions with each other or with cotton or rayon. Such other fibers which may be used include natural fibers such as flax, wool, etc.; synthetic or man-made fibers including the polyamide fibers such as nylon 6/6, nylon 6/ 10, nylon 6; polyethylene tereph-thalate polyester fibers such as Dacron" and Kodel; acrylic fibers such as Orlon, Acrilan and Dyne; cellulose ester fibers such as Celanese and Arnel, vinyl fibers such as Vinyon and saran; polyolefins such as polyethylene and polypropylene; etc. Such fibers are cardable and vary in length from about /2 inch up to about 2 /2 inches or more in length.

The weight of the fibrous web which is bonded by the techniques of the present invention will vary widely, depending primarily upon its intended use. Web weights of as low as about 200 grains per square yard may be employed, although such weights are sometimes more difficult to handle. Web weights up to about 4000 grains per square yard or even heavier may be used. Within the more commercial aspects of the present invention, however, we'b Weights of from about 500 to about 2000 grains per square yard are contemplated.

The present invention will also be described in greater particularity with reference to a durable, non-migratory binder, such as viscose or regenerated cellulose, as the preferred binder for the nonwoven fabric. Such, however, is for illustrative purposes and is not intended to be lirnitative of the use of other binders such as other cellulosic binders including hydroxyethyl cellulose, carboxymethyl cellulose, etc.; the emulsion type synthetic binders including acrylic binders, such as ethyl acrylate, or vinyl binders, such as polyvinyl chloride and polyvinyl acetate; solvent system binders such as polyvinyl chloride in toluene or xylene; etc. Naturally, when a washable or launderable bonded nonwoven fabric is desired, a durable binder is selected.

The particular print pattern which is selected for the application of the binder is largely a matter of choice, depending upon many factors notably the strength, softness, durability, flexibility or other properties and characteristics desired or required in the bonded nonwoven fabric. Typical examples of print patterns suitable for the application of the present invention are noted in US. Patents 2,705,687, 2,705,688, and pending patent application Serial No. 711,580, filed January 28, 1958, now Patent No 3,009,822.

The surface coverage of the particular print pattern selected may be varied within wide limits, depending upon many factors notably the strength, softness, durability, flexibility, or other properties desired or required in the bonded nonwoven fabric. The surface coverage is also dependent upon the type of printing used to apply the binder. For example, when double opposed printing rolls are used and the nonwoven fabric is printed substantially simultaneously on both sides in a single pass, the control over the registry of the printing on both sides is accurately maintained and higher surface coverages can be tolerated. However, when the nonwoven fabric is bonded in two successive stages, one for each side of the nonwoven fabric, the control over the registry of the printing is less and consequently lower surface coverages are normally used. Surface coverages of from about 5 percent up to about 35 percent are generally applicable, although, within the more commercial aspects of the present invention, surfacecoverages of from about 10 percent to about 27 percent are preferred, with optimum values in the range of from about 14 percent to about 22 percent of the surface area of the bonded nonwoven fabric.

The most important factor to be considered in the selection of a particular binder print pattern or in the use of a particular printing technique is the precentage of common binder contact which is defined herein as the percentage of the area in which the binders on each side of the nonwoven fabric are in common contact in the middle of the nonwoven fabric. In the case of double opposed printing rolls wherein binder registry can be accurately controlled, the common binder contact can be effectively maintained at percent of the total surface of the nonwoven fabric. Such a low percentage is highly desirable. However, when bonding takes place in two successive stages, one for each side of the nonwoven fabric, the control over the registry is reduced and consequently binder patterns and surface coverages must be so selected that the average common binder contact be maintained at less than about percent of the total surface of the bonded nonwoven fabric. Within the more commercial aspects of the present invention, however, the average common binder contact is preferably less than about 3 percent of the total surface of the bonded nonwoven fabric.

The total weight of the binder which is applied to the fibrous web will vary widely, depending upon many factors such as the nature, weight and intended use of the bonded nonwoven fabric. Normally, from 2 percent to about 25 percent by weight of binder, based on the weight of the fibrous web has been found sufficient. However, for lighter fabrics, down to about 1 percent by weight is often found sufficient, whereas for heavier fabrics intended for more rugged use, up to 35 percent by weight or even more is required.

In the following specification and accompanying drawings, there is described and illustrated preferred embodiments of the invention but it is to be understood that the inventive concept is not to be considered limited to the embodiments disclosed except as determined by the scope of the appended claims. Referring to the accompanying drawings:

FIGURE 1 is a diagrammatic, schematic showing of a method of applying binder material to both sides of a fibrous web in two successive separate steps;

FIGURE 2 is a diagrammatic, fragmentary showing of the back-up roll and the print cylinder of FIGURE 1, showing the relationship of the binder-carrying recesses; FIGURE 3 is a diagrammatic, schematic showing of a method for applying binder material to both sides of a fibrous web substantially simultaneously;

FIGURE 4 is a diagrammatic, fragmentary showing of the two printing rolls of FIGURE 2, showing the relationship and physical, geometric registry of the binder-carrying recesses;

FIGURE 5 is a diagrammatic, fragmentary showing of a bonded nonwoven fabric in plan view showing the relationship and physical, geometric registry of the applied binder areas;

FIGURE 6 is a diagrammatic, fragmentary cross-section of the bonded nonwoven fabric of FIGURE 5, taken on the line 6-6 thereof, showing the relationship and physical geometric registry of the applied binder areas; and

FIGURE 7 is a diagrammatic, fragmentary cross-section of the bonded nonwoven fabric of FIGURE 5, taken at a different portion thereof, showing the relationship and physical, geometric registry of the applied binder areas thereat.

It is to be appreciated that FIGURES 1 through 7 are diagrammatic and that many of the lesser important details such as doctor blades, bearings, drives, belts, pulleys, fluid level controls, etc., have been omitted for the purposes of clarity.

In the embodiment of the invention shown in the drawings and with particular reference to FIGURE 1 thereof, there is shown a fibrous web F which is being advanced between the nip of a rotatable print roll or cylinder 10 and a rotatable back-up roll 12. The print cylinder 10 and the back-up roll are relatively adjustable so as to control the pressure exerted on the web passing therebetween. The print cylinder 10 is partially immersed in a bath 14 of binder 16 and rotation of the print cylinder in the binder bath fills the recesses 18 therein (see FIG- URE 2) whereby the binder is printed on one side of the fibrous web as it passes through the nip of the print cylinder and the back-up roll. The amount of binder printed on the fibrous web and the depth to which it penetrates depends upon many factors, such as, for example, the nature and condition of the fibrous web being bonded, the nature and condition of the binder being applied, the size and shape of the recesses in the print cylinder, etc. In the application of the present invention, these factors are so adjusted by techniques well known in the art that the binder penetrates generally about half way through the fibrous web.

After the fibrous web has passed through the nip of the print cylinder 10 and the back-up roll 12, it is guided over

rotatable guide rollers

20 and 22 and is then passed through the nip of a second rotatable print roll or cylinder 22 and a second rotatable back-up roll 24. The print cylinder 22 is partially immersed in a bath 26 of binder 28 and rotation of the print cylinder 22 therein results in printing of the binder on the fibrous web, although this time on the opposite side thereof, due to the reversal of the fibrous web over the

guide rollers

20 and 22. Again, the application of the binder is such that it penetrates generally about half way through.

The recesses on the second print cylinder 22 are positioned one-half a print-unit out of registry with the recesses on the first print cylinder 10 whereby, if ideal or at least fair operating conditions prevail, the binders will be printed out of registry, such as shown in the bonded nonwoven fabric illustrated in FIGURES 5 and 6. Loss of control over desired registry normally occurs when the fibrous web stretches or shrinks during its travel from the first binder printing to the second binder printing, and occurs also when the fibrous web shifts laterally during such travel. Out-of-registry may, therefore, be either in the lengthwise direction, or the crosswise direction, or both.

With regard to the bonded nonwoven fabric of FIG- URES 5 and 6, the print pattern comprises spaced columns of circular binder areas, with the circular binder areas 30 being printed on the top surface of the fibrous web and the circular binder areas 32 being printed on the bottom surface of the fibrous web. As noted in FIG- URE 6, the binder areas penetrate generally about half way through the fibrous web but do not meet each other because they are completely out of registry and consequently there is no common binder contact area.

In the event that ideal or at least fair operating conditions do not exist and the fibrous web passes through the nip of the second print cylinder and the second back-up roll at such a time or with such positioning that the second binder printing is not completely out of registry with the first binder printing, there may be a common contact between the two binders and there will be formed an area of common binder contact, such as shown in FIGURE 7. In this figure, the binder areas 34 printed on the top surface of the fibrous web do meet the binder areas 36 printed on the top surface of the fibrous web and are in partial registry therewith.

In the application of the principles of the present invention, the print patterns are so selected, particularly with reference to their form and type as well as their surface coverages, that the average common binder contact area is less than about 5 percent, and preferably less than about 3 percent of the total surface of the bonded nonwoven fabric. If this principle is followed, then the outer surfaces of the fibrous web will be well bonded, lint free, and durable, Whereas the central portion will remain soft and relatively unbonded. Such creates good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

In the embodiment of the invention shown in FIG- URES 3 and 4, there is illustrated a fibrous web P which is being advanced over a guide roll 40 vertically downwardly between the nip of a rotatable print roll or cylinder 42 and an opposed rotatable print roll or cylinder 44. The print cylinder 42 is in rolling contact with a pick-up roll 46 which is partially immersed in a bath 48 of a binder 50. The print cylinder 44 is in rolling contact with a pick-up roll 52 which is partially immersed in a bath 54 of a binder 56. The print cylinder 42 and the print cylinder 44 are adjustable relatively with respect to each other, whereby the fibrous web F which passes therebetween is printed on both sides substantially simultaneously with the

binders

50 and 56. Again, the printing conditions are so adjusted by techniques well known in the art that each binder penetrates generally about half way through the fibrous web F.

The print cylinder 42 and the print cylinder 44 are driven in positive fashion by means of gearing (not shown) whereby the

recesses

62 and 64 therein are completely out of registry, as shown more particularly in FIGURE 4. Reference to this figure will reveal that the fibrous web F is printed substantially simultaneously by the print cylinders 42 and 44 and that such printing is accurately controlled by the geared driving of the print cylinders.

After the printed fibrous web passes through the nip of the print cylinders 42 and 44 it is guided over guide roll '58 and then advanced for further processing of the binder such as coagulation, regeneration, etc.

It is also to be noted that in this modification of the inventive concept in 'which the binder printing is con trolled and is out of registry, the binder may be permitted to penetrate more than about half way through the fibrous web inasmuch as there vis no opposed binder material on the other side of the fibrous web.

The invention will be further illustrated in greater detail by the following specific examples. It should be understood, however, that although these examples may describe in particular detail some of the more specific features of the invention, they are given primarily for purposes of illustration and the invention in its broader aspects is not to be construed as limited thereto.

Example I The starting fibrous mateiial is a 40-inch card web weighing about 1600 grains per square yard and comprising 50% by weight of bleached cotton and 50% by weight of viscose rayon staple fibers having a denier of about 1 /2 inches and a staple length of about 1 inches. This fibrous web is bonded by being passed successively through two pairs of binder-applying rolls, as illustrated in FIGURE 1. Both pairs of rolls apply viscose to the fibrous card web; one applying the viscose to one side and the other pair of rolls applying the viscose to the other side of the fibrous card web. The viscose binder is coagulated and regenerated by conventional techniques and the resulting bonded nonwoven fabric is washed and dried in standard apparatus.

The print patterns employed are the so-called crosshatch print patterns as described more particularly in US. Patent 2,705,687. The two print patterns are similar but are angularly reversed. Their geometric proportions are similar, however, and are: the angular relationship of the cross-hatch binder line to the long axis of the fibrous web is +30 for one and -30 for the other; the length of the cross-hatch is 0.406- inch; the width of the cross-hatch is 0.032 inch; the surface coverage of the print pattern, as measured on the printing roll, is 13%. The common binder contact area is determined from ten sample areas selected at random and is about 1% of the surface of the bonded nonwoven fabric.

Both surfaces of the bonded nonwoven fabric are wellbonded, lint-free, and durable; the central portion of the bonded nonwoven fabric is soft and relatively unbonded.

The bonded nonwoven fabric possesses good liquid absorbency, good liquid capacity, and low liquid strikethrough properties. It is useful as a lithographic wiping fabric, a cosmetic wiping fabric, and as a general wiping and cleaning cloth.

Example II I The procedures of Example I are followed substantially as set forth therein with the following exceptions: the card web comprises 100% viscose rayon fibers; the print patterns are diagonal lines, one print pattern on one side being +45 to the fiber orientation and the other print pattern on the other side being -45 to the fiber orientation; the width of each binder line is 0.015 inch; and there are 8 binder lines per inch. The surface coverage on each side is 12% of the surface area of the fibrous Web; the common binder contact area is 0.5% of the surface area of the bonded nonwoven web.

Both surfaces of the bonded nonwoven fabric are wellbonded, lint-free and durable; the central portion of the bonded nonwoven fabric is soft and relatively unbonded. The bonded nonwoven fabric possesses good liquid ab sorbency, good liquid capacity, and low liquid strikethrough properties. It is useful as a lithographic wiping fabric, a cosmetic wiping fabric, and as a general wiping and cleaning cloth.

Example III The starting fibrous material is a 40-inch card web weighing about 600 grains per square yard and comprislng viscose rayon staple fibers having a denier of about 1 /2 and a staple length of about 1%; inches. This fibrous web is bonded by being passed through the vertical-nip printing apparatus of FIGURES 3 and 4. Both rolls apply viscose substantially simultaneously to the fibrous cagd web; one roll to one side and one roll to the other si e.

The print patterns are wavydine print patterns which extend across the width of the fibrous web generally at about to the fiber orientation. The two print patterns are similar but are staggered or spaced so that they are completely out of registry. Their geometric proportions are similar, however, and are: the width of each line is 0.025 inch and there are 4 lines per inch. The surface coverage on each side is 10%. The common binder contact area is 0%. The viscose binder is coagulated and regenerated by conventional techniques known to the art and the resulting bonded nonwoven fabric is washed and dried in standard apparatus.

Both surfaces of the bonded nonwoven fabric are wellbonded, lint-free and durable; the central portion of the bonded nonwoven fabric is soft and relatively unbonded. The bonded nonwoven fabric possesses good liquid absorbency, good liquid capacity, and low liquid strikethrough properties. It is useful as a lithographic wiping fabric, a cosmetic wiping fabric, and as. a general wiping and cleaning cloth.

Example IV The procedures of Example HI are followed substantially as set forth therein with the exception that a different print pattern is employed. In this instance, the print pattern is a wavy line having a width of 0.035 inch and there are six such lines per inch. The surface coverage of the binder on each side is 21%. The common binder contact area is 0%.

Both surfaces of the bonded nonwoven fabric are wellbonded, lint-free and durable; the central portion of the bonded nonwoven fabric is soft and relatively unbonded. The bonded nonwoven fabric possesses good liquid absorbency, good liquid capacity, and low liquid strikethrough properties. It is useful as a lithographic wiping fabric, a cosmetic wiping fabric, and as a general wiping and cleaning cloth.

Example V The procedures of Example I are followed substantially as set forth therein with the exception that the binder is hydroxyethyl cellulose instead of regenerated cellulose. The bonded nonwoven fabric obtained is comparable to that obtained in Example I.

Example VI The procedures of Example III are followed substantially as set forth therein with the exception that a different binder is used. The binder is Rohm & Haas acrylic resin HA8. This resin is essentially prepared from ethyl acrylate and is a self cross-linking acrylic polymeric material. The bonded nonwoven fabric obtained is comparable to that obtained in Example III.

Although several specific examples of the inventive concept have been described, the same should not be construed as limited thereby nor to the specific features mentioned therein but to include various other equivalent features as set forth in the claims appended hereto. It is understood that any suitable changes, modifications and variations may be made without departing from the spirit and scope of the invention.

What is claimed is:

l. A method of making a bonded nonwoven fabric which comprises: applying to one side of a fibrous layer of overlapping, intersecting fibers a binder in a print pattern covering from about percent to about percent of the surface of that side of said fibrous layer; and applying to the other side of said fibrous layer a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said binder print patterns being in such registry with each other that the average common binder contact area is less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity and low liquid strike-through properties.

2. A method of making a bonded nonwoven fabric which comprises: applying to one side of a fibrous layer of overlapping, intersecting fibers a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and subsequently applying to the other side of said fibrous layer a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said binder print patterns being in such registry with each other that the average common binder contact area is less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity and low liquid strikedhrough properties.

3. A method of making a bonded nonwoven fabric which comprises: applying to one side of a fibrous layer of overlapping, intersecting fibers a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and substantially simultaneously applying to the other side of said fibrous layer a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said binder print patterns being in such registry with each other that the average common binder contact area is less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity and low liquid strikethrough properties.

4. A method of making a bonded nonwoven fabric which comprises: forming a fibrous layer of overlapping, intersecting fibers; applying -to one side of said fibrous layer a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and applying to the other side of said fibrous layer a binder in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said binder print patterns being in such registry with each other that the average common binder contact area is less than about 5 percent of the surface of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity and low liquid strikethroug properties.

5. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting fibers; a binder applied to one side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and a binder applied to the other side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good =1iquid capacity, and low liquid strike-through properties.

6. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting cellulosic fibers; a cellulosic binder applied to one side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and a cellulosic binder applied to the other side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said cellulosic binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

7. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting fibers; a binder applied to one side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that side of said fibrous layer; and a binder applied to the other side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that other side of said fibrous layer, said binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 3 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquids strike-through properties.

8. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting cellulosic fibers; a cellulosic binder applied to one side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that side of said fibrous layer; and a cellulosic binder applied to the other side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that other side of said fibrous layer, said cellulosic binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 3 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

9. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting fibers; a binder applied to one side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that side of said fibrous layer; and a binder applied to the other side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that other side of said fibrous layer, said binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively ainbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

10. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting cellulosic fibers; a cellulosic binder applied to one side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that side of said fibrous layer; and a eel lulosic binder applied to the other side of said fibrous layer in a print pattern covering from about 8 percent to about 25 percent of the surface of that other side of said fibrous layer, said cellulosic binders extending in- Wardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 5 percent of the area of said fibrous, layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

11. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting fibers; a binder applied to one side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and a binder applied to the other side of said fibrous layer in a print pattern covering from about 5 percent to about percent of the surface of that other side of said fibrous layer, said binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a cornrnon binder contact area having an average less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-throng properties.

12. A bonded nonwoven fabric comprising: a fibrous layer of overlapping, intersecting cellulosic fibers; a cellulosic binder applied to one side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that side of said fibrous layer; and a cellulosic binder applied to the other side of said fibrous layer in a print pattern covering from about 5 percent to about 35 percent of the surface of that other side of said fibrous layer, said cellulosie binders extending inwardly from said surfaces of said layers and having such a print pattern registry that they meet in a common binder contact area having an average less than about 5 percent of the area of said fibrous layer whereby the central portion of said fibrous layer is soft and relatively unbonded and the fibrous layer possesses good liquid absorbency, good liquid capacity, and low liquid strike-through properties.

References Cited in the file of this patent UNITED STATES PATENTS 2,545,952 Goldman Mar. 20, 1951 2,670,315 Rider Feb. 23, 1954 2,880,111 Drelieh et al. Mar. 3 l, 1959 2,971,857 Baxter Feb. 14, 1961 3,009,822 Drelieh et al Nov. 211, 1961 3,043,721 Burns July 10, 1 962

Claims

1. A METHOD OF MAKING A BONDED NONWOVEN FABRIC WHICH COMPRISES: APPLYING TO ONE SIDE OF A FIBROUS LAYER OF OVERLAPPING, INTERSECTING FIBERS A BINDER IN A PRINT PATTERN COVERING FROM ABOUT 5 PERCENT TO ABOUT 35 PERCENT OF THE SURFACE OF THAT SIDE OF SAID FIBROUS LAYER; AND APPLYING TO THE OTHER SIDE OF SAID FIBROUS LAYER A BINDER IN A PRINT PATTERN COVERING FROM ABOUT 5 PERCENT TO ABOUT 35 PERCENT OF THE SURFACE OF THAT OTHER SIDE OF SAID FIBROUS LAYER, SAID BINDER PRINT PATTERNS BEING IN SUCH REGISTRY WITH EACH OTHER THAT THE AVERAGE COMMON BINDER CONTACT AREA IS LESS THAN ABOUT 5 PERCENT OF THE AREA OF SAID FIBROUS LAYER WHEREBY THE CENTRAL PORTION OF SAID FIBROUS LAYER IS SOFT AND RELATIVELY UNBONDED AND THE FIBROUS LAYER POSSESSES GOOD LIQUID ABSORBENCY, GOOD LIQUID CAPACITY AND LOW LIQUID "STRIKE-THROUGH" PROPERTIES.