US3512230A - Method and apparatus for the production of nonwoven fabrics - Google Patents
Method and apparatus for the production of nonwoven fabrics Download PDFInfo
- Publication number
- US3512230A US3512230A US567638A US3512230DA US3512230A US 3512230 A US3512230 A US 3512230A US 567638 A US567638 A US 567638A US 3512230D A US3512230D A US 3512230DA US 3512230 A US3512230 A US 3512230A
- Authority
- US
- United States
- Prior art keywords
- filaments
- production
- nonwoven fabrics
- undulations
- spreading
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- D—TEXTILES; PAPER
- D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
- D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
- D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
- D04H3/02—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments
-
- D—TEXTILES; PAPER
- D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
- D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
- D02G1/00—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics
- D02G1/14—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics using grooved rollers or gear-wheel-type members
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S493/00—Manufacturing container or tube from paper; or other manufacturing from a sheet or web
- Y10S493/967—Dunnage, wadding, stuffing, or filling excelsior
Definitions
- a nonwoven fabric web is produced by extruding a plurality of tacky, closely spaced, parallel filaments downwardly from a spinneret in a common plane to a mechanical crimping device, which forms in the filaments, crimps or undulations disposed in parallel planes extending at right angles to said common plate, and ether passing the crimped filaments over a convex support surface, while simultaneously spreading the filaments apart, or depositing the filaments on a resilient moving surface which simultaneously entangles the undulations and stretches sideways to draw the entangled filaments apart.
- This invention relates to a method by which textile structures and reticulated fabrics of the kind commonly called nonwoven fabrics and, more particularly, this invention is directed to a method for the production of nonwoven fabrics in the form of high-bulk webs and felts.
- said prior nonwoven fabrics are exposed to a number of defects. They consist of discontinuous filaments and thus they are in any case more or less liable to a mutual sliding and dislocation.
- the individual filaments are present, in the fabric, along a substantially rectilinear trend and, due to their inherent inextensibility, they overcome, until they break, any tendency towards the elongation of the nonwoven fabric along the direction corresponding to their orientation.
- Said known nonwoven fabrics are then gradually decomposed as they are subjected to stresses and also to vibrations in different directions.
- Nonwoven fabrics are also known, which consist of continuous filaments more or less randomly arranged along long tortuous paths. These fabrics require, however, clumsy and quite uncontrollable processes for their production and also very low ratios between the web production capability and the filament output, all these facts United States Pat ent 0 Patented May 19, 1970 being limitations from an economical standpoint and, moreover, their structure is such that the intersection points of the filaments are relatively few, that which puts limitations on the mechanical properties also.
- a complementary object of this invention is to provide a production method affording, in combination with the above listed technical effects and advantages, the advantageous feature of permitting an economy in production means and implementations.
- the method consists in producing a plurality of continuous filaments of a spinnable man-made or synthetic material by causing said filaments to be advanced over a plane and in a parallel and close side-by-side relationship, subjecting said filaments to a mechanical and, if necessary, also thermal crimping step, or to a treatment capable of imparting closely arranged undulations on the individual filaments, said undulations lying in parallel planes which are closely spaced apart and substantially perpendicular to the original planes of the filaments so that, due to the closeness of said filaments and their tendency towards being deviated from said parallel planes, the filaments come into mutual contact at a plurality of points, giving rise to adhesion phenomena which are effected or enhanced by the nature of the surface of the filaments and/or by the presence of binders and adhesives on their surfaces, and thereafter causing the mass of filaments so treated to be advanced over one or more resting surfaces on which said mass is encouraged to expand while its feeding speed is reduced.
- the spreading effect that is the shifting apart of originally contacting filaments, and, possibly the shrinking elfect due to the decrease of their feed velocity, is conducive to a widening and extension of the undulations or a tendency towards taking up an undulated outline as caused by said crimping step, while in practice the points of mutual contact and interlock between adjacent filaments, which existed prior to laying the filament mass on said rest surfaces, and multiplied.
- Said mechanical treatment stages can obviously be integrated, proceeded, followed by, or alternated with, other conventional treatment stages, either mechanical or nonmechanicai, of textile filaments and yarns.
- the individual conventionally drawn filaments could-undergo setting, sizing or application of adhesives if necessary.
- the reticulated structure thus obtained which is not stable, is stabilized and integrated by methods which are known in the field of nonwoven fabrics and which involve the application of adhesives and impregnation agents or the lamination with plastic sheets, a nonwoven fabric proper being obtained in the former case, and a reinforced sheet or laminate in the latter.
- a plurality of filaments is produced by a conventional extruder 11 comprising a spinneret 12 whose nozzles are in alignment and closely spaced apart so that the filaments of said plurality 10 are closely adjoining to one another. Said close side-by-side relationship among the several filaments, which lie in a single plane, could, however, be obtained in the not immediate neighbourhood of the spinneret output end but somewhat distant therefrom.
- the filaments of the plurality 10- could undergo conventional treatments in order to be converted into yarns or anyhow into a condition of practical utility.
- these treatments will comprise one or more drawing steps such as diagrammatically shown in FIG. 1 at 13.
- drawing steps such as diagrammatically shown in FIG. 1 at 13.
- steps suitably shifted, could be effected downstream of the drawing step, for example in the position shown at 14, the sequence in which said steps are performed having no criticality for this invetnic-n, but depending on the nature of the filaments and by expediency and conveniency considerations.
- the crimping device impart to the individual filaments unduiat-ions having an amplitude which is considerably wider than the interspace between closely adjoining filaments present in the plurality 10 at the input end of the device.
- said device will comprise a tumbler-shaped roller 20 on whose surface the filaments are forced mutually to spread apart in a direction transverse to their direction of advance.
- the individual undulations are stressed by the convex surface of the roller so as to widen their amplitude and are possibly shortened when the surface speed of the roller is reduced, there being also the possibility that they assume a spirallike und-ulation.
- the resultant product 21 takes up and maintains in this way the characteristics of a nonwoven fabric whose reticulated pattern is surprisingly regular and anyhow exhibits the most desirable characteristics.
- These undulations have not a sinusoidal regular outline but tend to assume a statistical desirable trend and thus they can have sharp deviations and be arranged as skew lines within the thickness of the reticulated structure.
- each filament can have wider curves and deviations superposed to the tiny angular deviations outlined above.
- the amplitude of the undulations is a small fraction of the fabrics width and could even be as small as a fraction of a millimeter, even though it is, as a rule, in the order of magnitude of a few millimeters.
- the regular conveyance under the conditions of spreading and speed reduction can be assisted by encouraging the adherence of the filaments to the receiving surface, for example by employing roughened surfaces and/or surfaces provided with points, tooth-like projections or others.
- the spreading of the material can obviously be earned out in two stages, or more, over cascade positioned spreading devices such as the tumbler-shaped rollers 23 of F IG. 2, between which rolls 24 can possibly be interposed which, in addition to facilitating the transfer of materials from the one of the tumbler-shaped rollers 23, equalize the speed slackening of the material from the speed value V to the speed value V said rolls 24 being specially driven at different and subsequently decreasing surface velocities.
- the crimped and adjoining filaments of the plurality 16 are laid on a conveyor belt 25 made of a resiliently extensible material, for example of rubber, borne and caused to advance for example by means of chains 26 and 27 which operate in spread out planes so as to obtain the gradual spreading of the undulated filaments which are interlocked at a plurality of points of the textile reticulation of the nonwoven fabric 21.
- a conveyor belt 25 made of a resiliently extensible material, for example of rubber
- the receiving and spreading surface can also be advantageously embodied so that a portion thereof undergoes a shrinking effect and a spreading effect simultaneously with respect to the direction of advance.
- Said surface can be, for example, formed by a conveyor belt 28 of a deformable material so that every dimensional variation in one direct-ion is conducive to an opposite dimensional variation in a direction transverse with respect to the former direction, for example a belt having a reticulated net structure and made of rubber or another material.
- Said conveyor belt 28 could also be mounted about capstan-shaped rollers 29 and tumbler shaped rollers 30, capable of inducing, respectively, a shrink-ing effect and a transverse spreading of the belt 28 and having a greater and a smaller surface velocity, respectively. Therefore, the material being fed over the upper lap of the belt 28 will undergo a progressive reduction of its translational speed from V to V due to the gradual shortening of the material of the belt as a function of the gradual widening thereof.
- a method for producing nonwoven fabrics comprising subjecting a plurality of parallel, closely adjacent and coplanar filaments to a mechanical crimping operation to impart to said filaments undulations disposed in planes substantially perpendicular to the plane of said filaments, laying said thus undulated filaments on a receiving sur face to overlap and interlock with the undulations of adjacent filaments, spreading the filaments laterally to space them apart from each other, whereby a nonwoven fabric structure is formed consisting of continuous undulated filaments, each one of which overlaps and is interlocked with at least a part of an adjacent undulated filament where their undulations cross, the filaments being spread in a plane which is transverse to the feed direction of the filaments, the spreading of the filaments being accompanied by a simultaneously shortening of the fabric, continuously advancing said receiving surface during the deposit of said filaments thereon, inducing a progressive increase in width of said receiving surface during the advance thereof, and temporarily adhering substantially every undulation of the filaments on said surface thus compelling said undulations
- Apparatus for the production of nonwoven fabrics comprising means for producing a plurality of closely spaced, parallel, continuous filaments disposed in a common plane, mechanical crimping means connected to the output of said filament producing means to crimp said filaments and form therein undulations extending perpendicular to said common plane, a supporting surface engageable with the crimped filaments to displace the undulations thereof in directions which cause the undulations to overlap and interlock thereby to hold said filameans together in the form of a nonwoven fabric, said supporting surface being formed to spread said filaments laterally of one another, and said surface being formed of an extensible material which can be extended at least transverse to the direction of advance of the filaments so as to obtain a transverse spreading of said filaments.
Landscapes
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Mechanical Engineering (AREA)
- Nonwoven Fabrics (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT1713365 | 1965-07-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3512230A true US3512230A (en) | 1970-05-19 |
Family
ID=11149895
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US567638A Expired - Lifetime US3512230A (en) | 1965-07-29 | 1966-07-25 | Method and apparatus for the production of nonwoven fabrics |
Country Status (7)
Country | Link |
---|---|
US (1) | US3512230A (it) |
AT (1) | AT300714B (it) |
BE (1) | BE684855A (it) |
CH (1) | CH509450A (it) |
DE (1) | DE1635636A1 (it) |
GB (1) | GB1154465A (it) |
NL (1) | NL6610726A (it) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3681821A (en) * | 1970-01-19 | 1972-08-08 | Thomas M Buck | Method and apparatus for dephasing and entangling crimp yarn |
US3799715A (en) * | 1973-02-01 | 1974-03-26 | I Miura | Apparatus of making wrapping material for annular goods |
US3852152A (en) * | 1968-03-21 | 1974-12-03 | Akzona Inc | Resilient cushion |
US3930086A (en) * | 1971-01-05 | 1975-12-30 | Johnson & Johnson | Apertured nonwoven fabrics |
US3929542A (en) * | 1970-11-03 | 1975-12-30 | Basf Farben & Fasern | Non-woven webs of filaments of synthetic high molecular weight polymers and process for the manufacture thereof |
USRE28680E (en) * | 1971-01-05 | 1976-01-13 | Johnson & Johnson | Apertured nonwoven fabrics and methods of making the same |
WO1981002172A1 (en) * | 1980-01-25 | 1981-08-06 | I Reba | System and method for dispersing filaments |
US4351683A (en) * | 1967-10-19 | 1982-09-28 | Minnesota Mining And Manufacturing Company | Method of forming web material |
US5009732A (en) * | 1987-09-18 | 1991-04-23 | Bridgestone Corporation | Method of manufacturing member for use in tire including engaging wires between gears |
US5078935A (en) * | 1986-09-29 | 1992-01-07 | Mitsui Petrochemical Industries, Ltd. | Method of producing a very soft polyolefin spunbonded nonwoven fabric |
US5776404A (en) * | 1993-06-16 | 1998-07-07 | Rhodia Acetow Aktiengesellschaft | Method of making multiple width fiber strip |
US6013347A (en) * | 1997-07-16 | 2000-01-11 | 3M Innovative Properties Company | Method of continuous tone imaging to provide an imaged high loft mat product |
US6440192B2 (en) * | 1997-04-10 | 2002-08-27 | Valeo | Filtration device and process for its manufacture |
US20090075547A1 (en) * | 2007-09-19 | 2009-03-19 | Rotter Matin J | Cleaning pads with abrasive loaded filaments and anti-microbial agent |
US20100123267A1 (en) * | 2008-11-14 | 2010-05-20 | Tsinghua University | Method for stretching carbon nanotube film |
US20130161858A1 (en) * | 2010-09-15 | 2013-06-27 | Hiroyuki Sasaki | Apparatus for manufacturing a netted structure and method for manufacturing a netted structure |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3645330C2 (de) * | 1986-02-07 | 1999-10-07 | Reifenhaeuser Masch | Vorrichtung zur Herstellung eines Fadenvlieses aus verstreckten Filamenten aus einem synthetischen Polymer |
DE4320303C1 (de) * | 1993-06-18 | 1995-02-16 | Rhodia Ag Rhone Poulenc | Mehrfachbreiter Faserstreifen sowie ein Verfahren und eine Vorrichtung zu dessen Herstellung |
DE10302079B4 (de) * | 2003-01-21 | 2006-04-20 | Corovin Gmbh | Vorrichtung und Verfahren zur Herstellung von gekräuselten Spinnvliesfasern oder gekräuselten schmelzgeblasenen Vliesfilamenten aus geschmolzenem thermoplastischen Material |
DE102014002360A1 (de) * | 2014-02-18 | 2015-08-20 | Beumer Gmbh & Co. Kg | Transportvorrichtung mit einem endlosen bandförmigen Transportelement |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2067251A (en) * | 1933-04-21 | 1937-01-12 | Celanese Corp | Manufacture of textile materials |
US2399258A (en) * | 1943-03-20 | 1946-04-30 | American Viscose Corp | Novel filamentous product and method of making it |
US2407548A (en) * | 1940-08-01 | 1946-09-10 | Fibre Products Lab Inc | Fibrous structural material and method and apparatus for making same |
US2778065A (en) * | 1951-08-14 | 1957-01-22 | British Rayon Res Ass | Method of and means for continuously spreading filaments |
US3016581A (en) * | 1957-11-07 | 1962-01-16 | Eastman Kodak Co | Apparatus for opening continuous multifilament crimped tow |
US3101521A (en) * | 1959-06-25 | 1963-08-27 | Spunize Co Of America Inc | Method of producing crimped continuous filament yarn |
US3148101A (en) * | 1958-06-26 | 1964-09-08 | Celanese Corp | Process for making non-woven batt |
US3235442A (en) * | 1962-07-30 | 1966-02-15 | Du Pont | Crimped tow of polyester filaments |
US3235935A (en) * | 1962-03-09 | 1966-02-22 | Dunlop Rubber Co | Method of making synthetic fibre felt |
US3391048A (en) * | 1964-01-10 | 1968-07-02 | Eastman Kodak Co | Entangled nonwoven web product from parallel laid filamentary tows |
-
1966
- 1966-07-22 CH CH1065566A patent/CH509450A/it not_active IP Right Cessation
- 1966-07-25 US US567638A patent/US3512230A/en not_active Expired - Lifetime
- 1966-07-26 DE DE19661635636 patent/DE1635636A1/de active Pending
- 1966-07-26 GB GB33462/66A patent/GB1154465A/en not_active Expired
- 1966-07-29 AT AT07314/66A patent/AT300714B/de not_active IP Right Cessation
- 1966-07-29 NL NL6610726A patent/NL6610726A/xx unknown
- 1966-07-29 BE BE684855D patent/BE684855A/xx unknown
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2067251A (en) * | 1933-04-21 | 1937-01-12 | Celanese Corp | Manufacture of textile materials |
US2407548A (en) * | 1940-08-01 | 1946-09-10 | Fibre Products Lab Inc | Fibrous structural material and method and apparatus for making same |
US2399258A (en) * | 1943-03-20 | 1946-04-30 | American Viscose Corp | Novel filamentous product and method of making it |
US2778065A (en) * | 1951-08-14 | 1957-01-22 | British Rayon Res Ass | Method of and means for continuously spreading filaments |
US3016581A (en) * | 1957-11-07 | 1962-01-16 | Eastman Kodak Co | Apparatus for opening continuous multifilament crimped tow |
US3148101A (en) * | 1958-06-26 | 1964-09-08 | Celanese Corp | Process for making non-woven batt |
US3101521A (en) * | 1959-06-25 | 1963-08-27 | Spunize Co Of America Inc | Method of producing crimped continuous filament yarn |
US3235935A (en) * | 1962-03-09 | 1966-02-22 | Dunlop Rubber Co | Method of making synthetic fibre felt |
US3235442A (en) * | 1962-07-30 | 1966-02-15 | Du Pont | Crimped tow of polyester filaments |
US3391048A (en) * | 1964-01-10 | 1968-07-02 | Eastman Kodak Co | Entangled nonwoven web product from parallel laid filamentary tows |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4351683A (en) * | 1967-10-19 | 1982-09-28 | Minnesota Mining And Manufacturing Company | Method of forming web material |
US3852152A (en) * | 1968-03-21 | 1974-12-03 | Akzona Inc | Resilient cushion |
US3681821A (en) * | 1970-01-19 | 1972-08-08 | Thomas M Buck | Method and apparatus for dephasing and entangling crimp yarn |
US3929542A (en) * | 1970-11-03 | 1975-12-30 | Basf Farben & Fasern | Non-woven webs of filaments of synthetic high molecular weight polymers and process for the manufacture thereof |
US3930086A (en) * | 1971-01-05 | 1975-12-30 | Johnson & Johnson | Apertured nonwoven fabrics |
USRE28680E (en) * | 1971-01-05 | 1976-01-13 | Johnson & Johnson | Apertured nonwoven fabrics and methods of making the same |
US3799715A (en) * | 1973-02-01 | 1974-03-26 | I Miura | Apparatus of making wrapping material for annular goods |
WO1981002172A1 (en) * | 1980-01-25 | 1981-08-06 | I Reba | System and method for dispersing filaments |
US4334340A (en) * | 1980-01-25 | 1982-06-15 | Crown Zellerbach Corporation | System and method for dispersing filaments |
US5078935A (en) * | 1986-09-29 | 1992-01-07 | Mitsui Petrochemical Industries, Ltd. | Method of producing a very soft polyolefin spunbonded nonwoven fabric |
US5009732A (en) * | 1987-09-18 | 1991-04-23 | Bridgestone Corporation | Method of manufacturing member for use in tire including engaging wires between gears |
US5776404A (en) * | 1993-06-16 | 1998-07-07 | Rhodia Acetow Aktiengesellschaft | Method of making multiple width fiber strip |
US6440192B2 (en) * | 1997-04-10 | 2002-08-27 | Valeo | Filtration device and process for its manufacture |
US6013347A (en) * | 1997-07-16 | 2000-01-11 | 3M Innovative Properties Company | Method of continuous tone imaging to provide an imaged high loft mat product |
US20090075547A1 (en) * | 2007-09-19 | 2009-03-19 | Rotter Matin J | Cleaning pads with abrasive loaded filaments and anti-microbial agent |
US20100123267A1 (en) * | 2008-11-14 | 2010-05-20 | Tsinghua University | Method for stretching carbon nanotube film |
US8795461B2 (en) * | 2008-11-14 | 2014-08-05 | Tsinghua University | Method for stretching carbon nanotube film |
US20130161858A1 (en) * | 2010-09-15 | 2013-06-27 | Hiroyuki Sasaki | Apparatus for manufacturing a netted structure and method for manufacturing a netted structure |
US9334593B2 (en) * | 2010-09-15 | 2016-05-10 | Airweave Manufacturing Inc. | Apparatus for manufacturing a netted structure and method for manufacturing a netted structure |
Also Published As
Publication number | Publication date |
---|---|
DE1635636A1 (de) | 1971-03-25 |
BE684855A (it) | 1967-01-30 |
AT300714B (de) | 1972-07-15 |
GB1154465A (en) | 1969-06-11 |
CH509450A (it) | 1971-06-30 |
NL6610726A (it) | 1967-01-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3512230A (en) | Method and apparatus for the production of nonwoven fabrics | |
US3523059A (en) | Needled fibrous batting and method of making the same | |
US3468748A (en) | Nonwoven fabric with machine direction elasticity | |
US4188436A (en) | Non woven fabrics with pattern of discrete fused areas | |
US4223059A (en) | Process and product thereof for stretching a non-woven web of an orientable polymeric fiber | |
US4154889A (en) | Nonwoven fabric, method and apparatus for it's manufacture | |
US3713942A (en) | Process for preparing nonwoven fabrics | |
US4153664A (en) | Process for pattern drawing of webs | |
US4223063A (en) | Pattern drawing of webs, and product produced thereby | |
US3137746A (en) | Method of producing non-woven fabrics from thermoplastic film | |
US3059313A (en) | Textile fabrics and methods of making the same | |
US3137893A (en) | Apparatus and process for making apertured non-woven fabrics | |
US4151023A (en) | Method for the production of a nonwoven fabric | |
US3493452A (en) | Apparatus and continuous process for producing fibrous sheet structures | |
US3081500A (en) | Method and apparatus for producing apertured nonwoven fabric | |
US3485705A (en) | Nonwoven fabric and method of manufacturing the same | |
US3816228A (en) | Elastic nonwoven fabric | |
EP0127483B1 (en) | Elastic thermal bonded non-woven fabric | |
US3485695A (en) | Method of making a bonded poriferous non-woven textile fabric | |
US3879820A (en) | Apparatus for producing non-woven papermakers felt | |
US3303547A (en) | Cross stretching machine for nonwoven webs | |
US3255064A (en) | Process for mechanical crimping of fibers in sheet form | |
US3920511A (en) | Non-woven papermakers felt | |
US3819469A (en) | Stitched nonwoven webs | |
US3616159A (en) | Controllably oriented fibrous product |