Stock material or miscellaneous articles – Structurally defined web or sheet – Including aperture
Reexamination Certificate
1998-03-30
2001-03-27
Dixon, Merrick (Department: 1774)
Stock material or miscellaneous articles
Structurally defined web or sheet
Including aperture
C428S907000, C428S908800, C156S230000, C427S261000, C427S288000, C427S389900
Reexamination Certificate
active
06207250
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to treated textile fabric and to a method treating a fabric. The present invention more particularly relates to a method of preparing a liquid and stain resistant, antimicrobial textile fabric, and to the fabric so prepared.
BACKGROUND OF THE INVENTION
Stain resistance, water repellency and resistance to microbial growth are important in many uses of textile materials. In restaurants, for example, table cloths and seating upholstery often lack stain resistance and are subject to rapid water penetration. These properties necessitate frequent cleaning and/or replacement of such items. Although one generally views microbial growth as associated with fibers of biologic origin such as cotton, wool, linen and silk, in the field of marine use, the high relative humidity renders even synthetic polymer textiles, such as polyesters and polyamides, subject to microbial growth, which is also true of many other outdoor uses.
The term “water repellant” as used herein means essentially impermeable to water, i.e. treated textile can support a considerable column of water without water penetration through the fabric. Such behavior is sometimes termed “water resistant.” However, the last term generally implies a lesser degree of water repellency and further can be confused with the chemical use of “water resistant” to refer to coatings which are chemically stable to water or which will not be washed off by water. Hydrophobicizing topical treatments are incapable of providing the necessary degree of water repellency as that term is used herein.
Textile fabrics may be made water repellant by various processes. For example, textile fabrics may first be scoured with a soap solution and then treated with a composition which may include zinc and calcium stearates as well as sodium soaps. The long chain carboxylic acid hydrophobic compounds provide a limited amount of water repellency. It is also possible to render fabrics liquid resistant by treating the fabric with commercially available silicone, for example poly(dimethylsiloxane).
To overcome problems associated with water absorption and stain resistance, resort has been made to synthetic leathers and polyvinylchloride (vinyl) coated fabrics. However, these fabrics do not have the hand or feel of cloth. Moreover, although attempts have been made to render such materials water vapor permeable, these attempts have met with only very limited success, as evidenced by the failure of synthetic leather to displace real leather in high quality seating and footwear.
Applications of relatively small amounts of fluorochemicals such as the well known SCOTCHGUARD™ and similar compounds also may confer a limited degree of both water repellency and stain resistance. However, for optimal water repellency, it has proven necessary to coat fabrics with thick polymeric coatings which completely destroy the hand and feel of the fabric. Examples include vinyl boat covers, where the fabric backing is rendered water resistant by application of considerable quantities of polyvinylchloride latex or the thermoforming of a polyvinyl film onto the fabric. The fabric no longer has the hand and feel of untreated fabric, but is plastic-like. Application of polyurethane films in the melt has also been practiced, with similar results. However, unless aliphatic isocyanate-based polyurethanes are utilized, the coated fabric will rapidly weather.
It would be desirable to provide a fabric that allows water vapor to pass through the fabric while prohibiting the passage of liquid. It would also be desirable to provide a method of producing a liquid repellant, stain resistant, antimicrobial fabric. It would further be desirable to provide a liquid repellant, stain resistant, antimicrobial fabric that retains its natural hand and texture, is easy to handle, and economical to produce.
SUMMARY OF THE INVENTION
The present invention provides a water repellant, stain resistant, antimicrobial fabric that feels like fabric rather than plastic. The fabric of the present invention is treated with at least one treatment composition comprising both antimicrobial agent(s) and fluorochemical(s) to provide a water repellant, stain resistant, antimicrobial fabric.
BEST MODES FOR CARRYING OUT THE INVENTION
The water repellant, stain resistant, antimicrobial, fabric of the present invention retains its natural “hand” or texture and is therefore aesthetically and texturally appealing. The fabric of the present invention is also durable, easy to handle and economical to produce.
The fabrics useful in the present invention include, but are not limited to, woven, non-woven and knitted fabrics, and preferably yarn or piece dyed upholstery woven fabrics, of natural fibers, synthetic fibers and mixtures of natural and synthetic fibers. Suitable natural fibers include, but are not limited to, fibers of cotton, linen, ramie, silk, wool and the like. Suitable synthetic fibers include, but are not limited to, fibers of nylon, polyester, acrylic, rayon, acetate and the like. Suitable fabrics for use with the present invention include, but are not limited to, jacquards (i.e., fabrics manufactured from a jacquard loom), brocades, dobbys (i.e., fabrics manufactured from a dobby loom) and canvases.
The treating process of the subject invention involves, in a first step, treating the fabric with a penetrating topical composition, hereinafter referred to as the primary treatment composition. The primary treatment composition in its most basic nature, comprises a fluorochemical treating agent in substantial amount, one or more antimicrobial agents, such as microbicidides and/or mildewcides, and water. The nature of the primary treatment composition is such that the fabric is thoroughly treated by topically treating the fabric, the primary treatment composition covering equally well both sides (i.e., surfaces) of the fabric as well as pentrating the surfaces of the fabric to cover the interstitial spaces within the fabric. The fabric is then oven dried at elevated temperatures, for example, from 250° F. to 350° F. (121° C. to 177° C.), resulting in a primarily treated fabric. The primarily treated fabric is mildew resistant, stain resistant and water repellant. In addition, its tensile and tear strengths are markedly improved. Yet, the primarily treated fabric is very difficult to distinguish from untreated fabric by hand, feel, texture, or ease of handling.
Although the process described above creates a unique new textile material, the new textile material is generally not completely water repellant. Inspection of the primarily treated fabric against a light source reveals multitudinous “pinholes” which may ultimately allow water to pass through the fabric. To render the primarily treated fabric water repellant, one or more additional coating steps, or secondary treatments, may be necessary, depending on the degree of water repellency desired. The additional steps, if more than one, are the same, and involve the application of a high solids polymeric latex, containing an emulsion polymer with a glass transition temperature (T
g
) of between −45° C. and 0° C., to one side of the primarily treated fabric. The latex, which has a consistency that is similar to that of wallpaper paste or high solids wood glue, is rolled, sprayed, or otherwise applied to the primarily treated fabric which then passes under a knife blade, doctor blade, or roller that essentially contacts the primarily treated fabric surface, leaving a thin coating of about 1-5 oz/yd
2
, and preferably about 1.5 oz/yd
2
, of material. The coated primarily treated fabric is then oven dried at 250° F. to 350° F. (121° C. to 277° C.) resulting in a secondarily treated fabric.
The resulting secondarily treated fabric still retains excellent hand and feel, although being less drapeable than the untreated virgin fabric. Inspection against a light shows very few pinholes, which application of a somewhat thicker coating may further reduce. However, even with the relatively few pinholes, the secondarily treated fa
Bullock Kyle
Rubin Craig A.
Rubin Randy B.
Brooks & Kushman P.C.
Dixon Merrick
Hi-Tex, Inc.
LandOfFree
Treated textile fabric does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Treated textile fabric, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Treated textile fabric will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2502676