Classifications

• • A—HUMAN NECESSITIES
  • A41—WEARING APPAREL
  • A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
  • A41D13/00—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches
  • A41D13/05—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches protecting only a particular body part
  • A41D13/11—Protective face masks, e.g. for surgical use, or for use in foul atmospheres
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M10/00—Physical treatment of fibres, threads, yarns, fabrics, or fibrous goods made from such materials, e.g. ultrasonic, corona discharge, irradiation, electric currents, or magnetic fields; Physical treatment combined with treatment with chemical compounds or elements
• • A—HUMAN NECESSITIES
  • A41—WEARING APPAREL
  • A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
  • A41D31/00—Materials specially adapted for outerwear
  • A41D31/04—Materials specially adapted for outerwear characterised by special function or use
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B1/00—Cleaning by methods involving the use of tools
  • B08B1/10—Cleaning by methods involving the use of tools characterised by the type of cleaning tool
  • B08B1/14—Wipes; Absorbent members, e.g. swabs or sponges
  • B08B1/143—Wipes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/12—Layered products comprising a layer of synthetic resin next to a fibrous or filamentary layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
  • B32B5/16—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by features of a layer formed of particles, e.g. chips, powder or granules
• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
• • 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
  • D04H3/005—Synthetic yarns or filaments
• • 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
  • D04H3/016—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the fineness
• • 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
  • D04H3/08—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
  • D04H3/14—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with bonds between thermoplastic yarns or filaments produced by welding
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
  • D06B21/00—Successive treatments of textile materials by liquids, gases or vapours
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
  • D06M11/01—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with hydrogen, water or heavy water; with hydrides of metals or complexes thereof; with boranes, diboranes, silanes, disilanes, phosphines, diphosphines, stibines, distibines, arsines, or diarsines or complexes thereof
  • D06M11/05—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with hydrogen, water or heavy water; with hydrides of metals or complexes thereof; with boranes, diboranes, silanes, disilanes, phosphines, diphosphines, stibines, distibines, arsines, or diarsines or complexes thereof with water, e.g. steam; with heavy water
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M15/00—Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/22—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using vat dyestuffs including indigo
  • D06P1/221—Reducing systems; Reducing catalysts
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
  • D06P3/34—Material containing ester groups
  • D06P3/40—Cellulose acetate
  • D06P3/42—Cellulose acetate using dispersed dyestuffs
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
  • D06P3/34—Material containing ester groups
  • D06P3/52—Polyesters
  • D06P3/523—Polyesters using vat or sulfur dyes
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
  • D06P3/82—Textiles which contain different kinds of fibres
  • D06P3/8204—Textiles which contain different kinds of fibres fibres of different chemical nature
  • D06P3/8223—Textiles which contain different kinds of fibres fibres of different chemical nature mixtures of fibres containing hydroxyl and ester groups
  • D06P3/8228—Textiles which contain different kinds of fibres fibres of different chemical nature mixtures of fibres containing hydroxyl and ester groups using one kind of dye

Definitions

• the present invention relates to a nonwoven fabric having a relatively low level of ionic contaminates which is achieved by exposing the fabric to a deionized water wash, preferably, in-line with the nonwoven production process, thereby eliminating, or at least reducing, the need for an expensive and time consuming cleanroom laundering.
• the fabric is primarily comprised of continuous filament fibers and may be manufactured into such end- use products as cleaning wipes and protective clothing for cleanrooms and surface coating operations, such as automotive paintrooms. Also encompassed within this invention is a method for producing a nonwoven fabric having a relatively low level of ionic contaminates.
• U.S. Patent No. 5,229,181 to Diaber, et al. describes a knit fabric tube, only two edges of which must be cut and sealed, thereby reducing the contamination caused by loose fibers from the edges.
• U.S. Patent No. 5,271 ,995 to Paley et al. describes a wiper for a cleanroom environment that has reduced inorganic contaminants through the use of a specific yarn, namely "nylon bright.”
• Ions such as Na, Li, NH 4 , K, Mg, Ca, Fl, Cl, NO 4 , PO 4 , and SO 4 are generally inherently present in a textile fabric. These ions may be detrimental to a cleanroom environment, especially in the semi-conductor industry, because the ions: (a) can be transferred to the silicon wafer circuitry; (b) can cause corrosion on the wafer circuitry, and (c) can cause short circuit in the wafer circuitry. It is known that deionized water may be used to reduce or eliminate these ions from the fabric so they may be suitable for use, for example, in cleanroom applications.
• Deionized water acts as an attractant to the ions in the fabric so that the ions are pulled off the fabric and into the water, which can then be discarded or filtered for reuse.
• ion reduction or removal is achieved using a cleanroom laundry to wash the fabric, often in the form of wipers, to reduce ion content.
• a cleanroom laundry to wash the fabric, often in the form of wipers, to reduce ion content.
• this process is very expensive and time consuming and may detrimentally affect the physical properties of the fabric due to the conditions the wipers encounter during the wash cycle, such as overly aggressive agitation and rinsing and exposure to high temperature water and chemicals.
• Wipers may be made from knitted, woven, or non-woven textile fabrics.
• the fabric is typically cut into 9-inch by 9-inch squares. If a wiper is intended for use in a cleanroom environment, it is generally desirable to wash the fabric or wipers in a cleanroom laundry in order to remove and minimize contamination of the wipers prior to packaging.
• the cleanroom laundry may employ special filters, surfactants, sequestrants, purified water, etc. to remove oils, reduce particle count, and extract undesirable ion contaminates.
• the laundering process which is expensive and time consuming, may be overly aggressive and may detrimentally affect the physical properties of the fabric.
• any finishes applied to the surface of the fabric may be removed during the laundering process and the fabric edges may become unraveled or frayed, thereby leading to an undesirable increase in fiber particle contamination.
• careful and constant monitoring of the laundering equipment employed is necessary in order control the agitation, volume and duration of rinsing, and speed and duration of extraction.
• nonwoven webs produced from these processes have been produced for functional end- uses, such as for air filters, vehicle trunk linings, and roofing materials, with relatively low cost and little or no emphasis on characteristics such as drape and hand and moisture absorbency which are of considerable interest, for example, in cleanroom wiping cloths and protective clothing.
• an efficient, cost effective method is needed for achieving a nonwoven fabric having a relatively low level of particle contaminates and sufficient hand, drape, and moisture absorbency characteristics required for end uses such as cleanroom and paintroom wipers and protective clothing.
• nonwoven fabric having low ion content that is suitable for use as a wiping cloth or a protective garment in cleanrooms or surface coating operations, such as automotive paintrooms.
• the fabric is typically comprised of synthetic continuous filament fibers, and may more specifically be comprised of multi-component continuous filament fiber that is splittable along its length by chemical or mechanical action, which generally enhances the hand, drape, and moisture absorption properties of the fabric.
• the fabric is generally achieved by exposing the nonwoven material to a deionized water rinse, preferably in-line with the nonwoven production process.
• the deionized fabric may then be further processed, for example, into wiping cloths of various sizes or protective garments, that meet or exceed the requirements for cleanrooms or surface coating operations, without requiring exposure to a cleanroom laundering process, thereby saving substantial time and expense, and preserving the fabric's finishing characteristics.
• a further object of the current invention is to achieve a method for producing a nonwoven fabric having low ion content that may be suitable for use as a wiping cloth or a protective garment in cleanrooms or surface coating operations, such as automotive paintrooms.
• the nonwoven fabric is manufactured according to various nonwoven textile-manufacturing processes known to those skilled in the art.
• the fabric may then be exposed, preferably via an in-line production process, to a deionized water rinse, a drying process, and a take-up process. Thereafter, the fabric may undergo further processing into cleaning wipes or protective garments.
• the wipes and/or garments may then be used in cleanroom or surface coating applications without necessarily requiring a cleanroom laundering process, thereby saving substantial time and expense, and preserving the fabric's finishing characteristics.
• the current invention discloses a nonwoven fabric having reduced ion content, which may be incorporated into articles for use in cleanrooms and surface coating operations, and a method for producing such fabric.
• the fabric is first produced according to standard nonwoven manufacturing processes known to those skilled in the art. These production processes include spun-bonding, melt-blowing, wet laid, dry laid, thermal bonding, flash spinning, SMS (this is a combination of spun-bond, melt-blown, and spun-bond), SMMS (this is a combination of spun-bond, melt-blown, melt-blown, and spun-bond), and combinations thereof.
• the fabric may be comprised of continuous filament fibers that are unitary, single component fibers, multi-component fibers, or any combination thereof.
• the multi-component fibers may be splittable along their length by mechanical or chemical action.
• U.S. Patent Nos. 5,899,785 and 5,970,583, both assigned to Firma Carl Freudenberg and both incorporated herein by reference describe a spun-bonded nonwoven lap of very fine continuous filament and the process for making such nonwoven lap using traditional spun- bonded nonwoven manufacturing techniques.
• Such references disclose, as important raw materials, spun-bonded composite, or multi-component, fibers that are longitudinally splittable by mechanical or chemical action.
• mechanical action includes subjecting the spun-bonded nonwoven lap, or fabric, formed from such materials to high- pressure water jets (i.e., hydroentanglement) in order to separate the multi-component filaments into their individual filaments.
• the fibers may be of any fiber size, but they are preferably characterized by having a fiber size of less than 5 denier. Further, the fibers, when extruded as multi-component fibers, may be preferably characterized by having individual filament sizes of less than 1 denier.
• the fibers may be comprised of various fiber types including polyester, such as, for example, polyethylene terephthalate, polytriphenylene terephthalate, and polybutylene terephthalate; polyamide, such as, for example, nylon 6 and nylon 6,6; polyolefins, such as, for example, polypropylene, polyethylene, and the like; polyaramides, such as, for example, Kevlar®; polyurethanes; polylactic acid; and any combination thereof.
• polyester such as, for example, polyethylene terephthalate, polytriphenylene terephthalate, and polybutylene terephthalate
• polyamide such as, for example, nylon 6 and nylon 6,6
• polyolefins such as, for example, polypropylene, polyethylene, and the like
• polyaramides such as, for example, Kevlar®
• polyurethanes polylactic acid; and any combination thereof.
• the nonwoven fabric After the nonwoven fabric is produced, it is typically then exposed to a deionized water rinse to remove ions from the fabric. Exposure is preferable when executed in-line with the nonwoven production process, however, it may be executed in a process separate from the nonwoven production process.
• the deionized water rinse may be accomplished by immersion coating, padding, spraying, or by any other technique whereby one can apply a controlled amount of a liquid to a fabric. If, for example, a spray bar is used to apply the deionized water rinse, a vacuum slot may be used in conjunction with the spray bar to remove excess water from the fabric.
• the fabric is then dried. Drying may be accomplished by heating the fabric, drying the fabric at room temperature, or any combination thereof.
• Heating can be accomplished by any technique typically used in textile manufacturing operations, such as dry heat from a tenter frame, microwave energy, infrared heating, steam, superheated steam, autoclaving, etc. or any combination thereof. In choosing a drying method that involves the use of heat, it may be preferable to dry the fabric at a temperature of 300 degrees F or less, especially if the fabric is comprised, at least partially, of polyester.
• 6,189,189 discloses a method of producing a low contaminant wiper with high absorbency by heatsetting a polyester textile fabric at 300 degrees F or less to eliminate or reduce the formation of low molecular weight polymers or oligomers, also known as "trimer particles," which bloom to the surface of the fabric when exposed to high heatsetting temperatures. These trimer particles, when released from the fabric surface, lead to a detrimental increase in particle contamination.
• the fabric After drying, the fabric is generally rolled up, or taken up, and may be further processed into a variety of end-use products, such as, for example, wipers of varying sizes or protective garments.
• Wipers although ideal for use in cleanrooms or areas where coatings are being applied to a surface, they may be used for any end-use where it is 0 preferable to have a fabric with low particle contamination.
• protective garments such as booties, gowns, aprons, masks, gloves, etc., that are required for use in cleanrooms or surface coating environments, may have application in other industries, such as in hospital operating rooms, dental offices, veterinary surgical rooms, or any other industry where low contaminant fabrics are desirable.
• These end-uses may include sterile 5 drapes, tents, blankets, dental bibs, gauze, bandages, tape, etc.
• nonwoven fabric it may be desirable to expose the nonwoven fabric to mechanical processing techniques which increase the thickness and water absorption properties of the fabric.
• mechanical processing techniques which increase the thickness and water absorption properties of the fabric.
• This air impingement process typically creates saw-tooth waves having small bending radii which 5 travel down the fabric thereby breaking up, or weakening, some fiber-to-fiber bonds in the web so as to increase the fabric's hand, drape, thickness, and moisture absorption properties.
• the process may be added in-line with the nonwoven production process either before or after a deionized water rinse.
• the fabric may be exposed to this air impingement process after a hydroentanglement step while the fabric is still wet.
• the nonwoven fabric may then be rinsed with deionized water and dried as previously described.
• Yet another potentially preferred embodiment includes using deionized water, rather than tap water, to hydroentangle the fibers of a nonwoven fabric, preferably a spun-bonded nonwoven fabric.
• the fabric may be hydroentangled with deionized water expelled from high-velocity water jets and then exposed to one or more of the following treatments in any order: a) air impingement, b) rinsing again with deionized water, and c) drying.
• a chemical finish may be added to the surface of the fabric to enhance aesthetic and/or performance characteristics such as water absorption, water repellency, particle attraction, etc.
• the chemical finish may be applied at any time after the fabric has been formed. It may be preferable to add the chemical finish after a hydroentangling process, and if desired, after treatment with an air impingement process, but typically prior to the final deionized water rinse.
• the application of a chemical to the fabric may be accomplished by immersion coating, padding, spraying, foam coating, or by any other technique whereby one can apply a controlled amount of a liquid suspension to an article. Employing one or more of these application techniques may allow the chemical to be applied to the fabric in a uniform manner.
• An example of a chemical that may be used is disclosed in commonly assigned international publication number WO 01/80706. This publication discloses a particle attracting finish that may be applied to a textile fabric for the purpose of attracting and removing particulate contaminants from a surface.
• All examples utilized 100 g/m 2 spun-bonded nonwoven fabric comprised of continuous multi-component splittable fibers which have been exposed to the process of hydroentanglement with high-pressure water to cause the multi-component fibers to split, at least partially, along their length into individual polyester and nylon 6,6 fibers, according to processes described in the two Freudenberg patents earlier incorporated by reference.
• the fabric known by its product name as Evolon®, was obtained from Firma Carl Freudenberg of Weinheim, Germany.
• the fabric is comprised of approximately 65% polyester fibers and approximately 35% nylon 6,6 fibers.
• the fabric is typically available in at least two variations, standard and point-bonded. The standard variation has not been subjected to further bonding processes, such as point bonding. Point-bonding is the process of binding thermoplastic fibers into a nonwoven fabric by applying heat and pressure so that a discrete pattern of fiber bonds is formed.
• Table 1 show that there was no change in ion content for Li, NH 4 , K, and Mg, but that the ion content for PO 4 increased.
• the increase in PO 4 likely comes from the gloves worn by the person performing the fabric testing. This can be reduced, or eliminated, by using a nalgeen tong to handle the fabric, or by having the person performing the test wear a different type of glove.
• Table 1 also shows that there was a substantial decrease in ion content for Na, Ca, Fl, Cl, NO 4 , and SO 4 .
• the fabric of this invention achieves a low ion content of less than about 10,000 part per billion for every ion shown in Table 1 after a deionized water rinse. More preferably, the fabric of this invention achieves a low ion content of less than about 5,000 parts per billion for every ion shown in Table 1 after a deionized water rinse.
• Example 1 was repeated, except that the fabric used was the point-bonded version of Evolon® (rather than the standard version). The results are measured in parts per billion (ppb) and are shown in Table 2 below.
• Table 2 show that there was no change in ion content for Li, NH 4 , K, and Mg, but that the ion content for PO 4 and Fl increased.
• the increase in PO 4 likely comes from the gloves worn by the person performing the fabric testing. This can be reduced, or eliminated, by using a nalgeen tong to handle the fabric, or by having the person performing the test wear a different type of glove.
• Table 2 shows that there was a substantial decrease in ion content for Na, Ca, Cl, NO 4 , and SO 4 .
• the fabric of this invention achieves a low ion content of less than about 10,000 part per billion for every ion shown in Table 2 after a deionized water rinse. More preferably, the fabric of this invention achieves a low ion content of less than about 5,000 parts per billion for every ion shown in Table 2 after a deionized water rinse.
• the process of rinsing a fabric in deionized water to reduce or eliminate ion content may also be used for woven or knitted fabrics. It is likely that the deionized water rinse would be performed in a process separate from the weaving and knitting machines because of the manufacturing layouts typical for these fabric-forming processes usually entails a large number of machines symmetrically arranged together and because water is not normally an integral part of these textile production processes.
• the fabric of the present invention may be combined into a composite material such that the composite is comprised of one or more layers of the deionized fabric laminated together with one or more layers of polymeric film.
• Nonwoven, woven, and knitted fabrics may be included as part of the composite material as well.
• These composites may have end uses in products such as, for example, in a graphite composite laminate utilized in the aerospace industry for the space shuttle, where contamination is of prime concern because contaminants in this environment could react with liquid oxygen and ignite or explode.
• the above description and examples disclose the inventive nonwoven fabric having low ion content and the method for producing such nonwoven fabric.
• Low ion content is achieved by rinsing the nonwoven fabric in deionized water following the nonwoven production process, preferable in-line with the production process. This is advantageously achieved without the use of a cleanroom laundry, which typically increases the cost, complexity and time consumption of the production process.
• this method may be used in conjunction with other chemical or mechanical processes to produce a nonwoven fabric having improved aesthetic and/or performance characteristics.
• this invention provides expanded utility for cleanrooms, surface coating operations, and the medical, dental, and veterinary industry such that the fabric of the invention may be incorporated into wiping cloths, protective apparel, sterile drapes, sheets, tents, bandages, and any other article wherein it is desirable to manufacture an end-use product having low ion content.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Physical Education & Sports Medicine (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Dispersion Chemistry (AREA)
• Materials Engineering (AREA)
• Chemical Or Physical Treatment Of Fibers (AREA)
• Nonwoven Fabrics (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

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• 2003
  • 2003-03-19 JP JP2003580621A patent/JP2005521803A/ja active Pending
  • 2003-03-19 IL IL16367603A patent/IL163676A0/xx unknown
  • 2003-03-19 MX MXPA04008322A patent/MXPA04008322A/es unknown
  • 2003-03-19 EP EP03716710A patent/EP1488033A1/en not_active Withdrawn
  • 2003-03-19 AU AU2003220406A patent/AU2003220406A1/en not_active Abandoned
  • 2003-03-19 CN CNA038071223A patent/CN1643202A/zh active Pending
  • 2003-03-19 KR KR10-2004-7015410A patent/KR20040111444A/ko not_active Application Discontinuation
  • 2003-03-19 WO PCT/US2003/008462 patent/WO2003083196A1/en active Application Filing

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