Upholstery fabrics for automobile, train and aircraft seats produced from regenerative nature fibers

Abstract
A novel pure natural and regenerative automotive and aircraft upholstery fabric made from linen and blends of linen and cotton, bamboo, wool and/or viscose with physiological and fastness properties comparable with those of currently-used materials and meeting all the requirements of the automobile and aircraft industry.
Description

This disclosure relates to upholstery fabrics for use in transport seating and to methods of making them.


STATE OF THE ART

The fabrics used in the interiors of automobiles and aircraft are generally produced exclusively from artificial fibers, which in turn are derived from petroleum feedstocks. These include materials such as polyester (PES) and polypropylene. The production of such fibers involves the generation of considerable volumes of carbon (CO2). In addition, they are poorly biodegradable, which means that environmentally-conscious disposal is a problem. Finally, the prices of such materials are highly dependent on the price of crude oil, which has tended to increase over time, meaning that the prices of such fibers also tend to increase in line with this.


TECHNICAL PROBLEM AND ITS SOLUTION

This invention of a new and purely natural upholstery fabric for transport seating, particularly automobile, train and aircraft seats, now aims to replace previous petroleum-based synthetic fiber substrates such as polyester and polypropylene with pure or blended natural, regenerative raw materials.


This invention, therefore, provides an automobile or aircraft seat upholstery made exclusively of environmentally-friendly renewable natural fibers, characterized in that the major component is linen. The aim is to use long-fiber flax fibers and blends of linen with cotton, bamboo, wool and/or viscose (regenerated cellulose fiber), which are renewable natural fiber mixtures. The mixing ratios are between 1% to max. 100% by weight of pure linen.


Preference is given to mixtures of 50% linen and 50% cotton, bamboo and/or viscose-filament whereby the mixing ratio between cotton and/or other natural cellulosic fibers is each between 0% and 50% cotton and 0% up to max. 50% viscose-filament where the proportion of cotton can be replaced up to max. 40% by viscose filament.


In addition to physiological use advantages of natural comfort in modern motor vehicles and aircraft, ecologically-friendly biodegradability and the possibility of natural recovery of the raw material, the much-debated CO2 generation is reduced considerably in the production of the upholstery fabric hereinabove described. Studies (see e.g. Grafic: Nova Institute 2007; Eyerer & Reinhardt 2000, Pless 2001, BaFa 2006, Ifeu 2005 resp. SachsenLeinen 2006b and DaimlerChrysler 1997) show that the cumulative energy demand (CED) of natural fibers such as flax and hemp is reduced by up to 83% compared to that of petroleum-derived and glass fibers, as a result of the natural growth.


The independence of the natural fiber raw material from the extreme price fluctuations of petroleum-derived plastics such as polyester and polypropylene as a result of the fluctuations in oil prices, leads to further significant economical and cost advantages.


Another object of the invention is to provide a natural regenerated product as automobile and airplane upholstery fabric which in its physiological as well as colour fastness properties is equal to or better than those of the prior art, and that meets or improves the high performance demands of the automotive and aircraft industries.


Primarily the following requirements must be met or improved:

    • 1.) All abrasion resistance and tensile strength tested according to Martindale strength test as the most stringent test
    • 2.) Elongation test
    • 3.) Heat light fastness tested according to the FAKRA test method (the most stringent light fastness test)
    • 4.) Flame resistance
    • 5.) Rubbing fastness dry and wet
    • 6.) Staining resistance
    • 7.) Mold- and decomposition resistance (antibacterial finishing)


The economics of production and the product price have to be as good as, or better than, those of petroleum-based synthetic car upholstery fabrics.


To meet these requirements, new developments have been made to make this new product suitable for the automobile and aircraft industry so that the product of the invention is brought to a new state of the art. These are now described in more detail.


Optimization of Natural Fiber Blends

For automotive and aircraft upholstery fabrics produced from pure natural fibers, high standards with respect to fiber staple length, fiber quality, fiber surface and spin twisting must be met to meet the performance requirements such as tensile strength and abrasion resistance in the use of automobile and aircraft seats (Martindale test must meet minimum requirement of 50,000 revolutions).


It is desired to achieve a maximum surface quality of high quality fibers in combination with mixtures of fibers with smooth surfaces such as viscose filaments and the optimization of these with respect to their use. Such mixtures primarily include linen, cotton, bamboo, and viscose/modal fiber as filaments. The minimum requirements are fabric weights between 100 and 700 g/m2 (preferably between 200 and 600 g/m2).


Spinning and Weaving

The automotive upholstery surface structures and the fabric weights must comply with the requirements and demands of the automotive industry and match each other by selected yarn counts (fineness), optimal spin rotation (twist effect), weaves such as Panama, twill, satin, etc., density in warp and weft of the natural fiber blends and mixing ratios.


The minimum requirements are:

    • Fabric width: between 1 m and 3 m, preferably between 1.30 and 1.60 m
    • Fabric weight: between 100 and 700 g/m2, preferably between 200 and 600 g/m2
    • Density/10 cm: warp between 50 and 600, preferably between 100 and 500
    • weft between 50 and 300, preferably between 100 and 200
    • yarn fineness: warp 20-200 tex, preferably 40-60 tex
      • weft linen 50-300, preferably 100-200 tex


Here are 3 examples:


is Weaving sample 1: Blend: linen/cotton 50/50

    • Fabric width: 1.55 m
    • Fabric weight: 320 g/m2
    • Density/10 cm: warp: 155
      • weft: 152
    • Yarn fineness warp: Cotton Nm 20 (=50 tex)
    • weft: Linen Nm 9.6 (=103 tex)


Weaving sample 2: Blend: linen/Cotton 50/50

    • Fabric width : 1.53 m
    • Fabric weight: 430 g/m2
    • Density/10 cm: warp: 321
      • weft: 146
    • Yarn fineness: warp: Cotton 50 tex
      • weft: Linen 170 tex


Weaving sample 3: Blend: Linen/Cotton 50/50

    • Fabric width: 1.52 m
    • Fabric weight: 375 g/m2
    • Density/10 cm: warp: 416
      • weft: 138
    • Yarn fineness: warp: Cotton 50 tex
      • weft: Linen 110 tex


Weaving sample 4: Blend: Linen/Cotton 50/50 bleached

    • Fabric width : 1.49 m
    • Fabric weight: 440 g/m2
    • Yarn turning : Cotton Nm 20/1 (=50 tex),
      • turns: −612/m
      • Linen Nm 6.8 (=140 tex),
      • turns −309/m


Knitted goods can also be employed.


Pretreatment

A further step in achieving the desired requirements is the use of a state-of-the-art pretreatment for linen and linen/cellulose mixtures, such as desizing, demineralization , bleaching, as well as a special mercerization process to reduce the fiber abrasion behavior and to increase the required abrasion fastness according to the Martindale test (minimum 50,000 revolutions).


The mercerization is carried out with highly concentrated caustic soda liquor and some alkyl sulfonate under fabric tension, for example, by the following method:


Recipe: 8.0 ml/kg alkylsulfonate

    • 743.0 ml/kg caustic soda 30° Bé


Treatment: 60 sec. immersion time and thereafter at least 2 min batching time under fabric tension

    • rinsing: at 25° C./70° C./25° C. each 3 min immersion time
    • neutralization: with Sirrix™ NE fl. (Clariant)


An additional advantageous effect of the mercerization is that the dyestuff build-up and the through-dyeing, particularly for deep shades such as black, is significantly improved.


First sample: blend sample cotton/linen 50/50 bleached, non-mercerized


Second sample: blend sample cotton/linen 50/50 bleached and mercerized.


Dyeing Process

A natural fiber automotive upholstery fabric made from linen and blends with cotton or other cellulosic fibers such as bamboo and viscose must be dyed with dyestuffs quite different from those used for polyester. While polyester must be dyed with disperse dyestuffs, this inventive new product is primarily dyed with reactive, substantive, vat or sulphur dyestuffs. For reasons of the high fastness requirements for this intended use, reactive dyes are preferred for this application.


Another important feature of this invention is that the high light-fastness and high heat temperature light-fastness (several times FAKRA-heat temperature light-fastness) required by the automobile industry, achievable by the use, for example, of disperse dyestuffs on PES, can now also be achieved by this invention by using specifically selected reactive dyestuffs on natural cellulose fibers such as linen and its abovementioned blends with cotton and other mixtures with cellulose fibers such as viscose and bamboo.


Another important aspect of this invention is, therefore, a careful selection of suitable reactive dyestuffs with high light fastness as individual dyestuffs and as components for high light fastness trichromatic blends from existing reactive dyestuff ranges.


All single and multiple anchor reactive dyestuffs, as well as sulphur and vat dyes, may be used. In the reactive dyestuff field, the following reactive components can be used:


dichlorotriazine, fluorochloropyrimidine (FCP), dichloroquinoxaline, mono-fluorotriazine, 2× monofluorotriazine, monochlorotriazine+vinylsulfone, trifluoropyrimidine, monofluorotriazine/monochlorotriazine+vinylsulfone, fluorochloropyrimidine/monochlorotriazine+vinyl sulfone, vinyl sulfone, or 2× vinylsulfone,monochlorotriazine, 2× monochloro-triazine, monochlorotriazine modified, trichloropyrimidine.


Preference is given to specifically selected reactive dyestuffs based on single/multiple anchor fluorochlorpyrimidine as the main reactive component.


In order to achieve the light- and FAKRA-high temperature fastness (dependent on the degree of dyestuff fixation) on the one hand, and, on the other hand, a highly productive economic dyeing process, the dyeing process must be optimised.


The following suitable dyeing processes are preferred:

    • 1.) Cold Pad Batch Process (CPB) as semi continuous process
    • 2.) E-control process (new development of A. Monforts(ICI, EP 081016) completely continuous process.
    • 3.) Pad Dry Thermofix Process, completely continuous process
    • 4.) Pad Dry Steam Process, completely continuous process
    • 5.) Chemical Pad Steam Process, completely continuous process
    • 6.) Exhaustion Process, discontinuous process in piece
    • 7.) Exhaustion Process, discontinuous process in yarn


The weights of fabric in automotive upholstery goods are between 100 and 700 g/m2, preferably between 300and 600 g/m2 and most preferably about 400 g/m2. When using qualities of around 400 g/m2, it must be ensured, on the one hand, that a very good dye penetration is achieved, and on the other hand, that the most economical dyeing process is used. In order to reconcile both requirements, there exists, in addition, on the part of the chemistry, the possibility of using special dyeing liquor additives such as 10-60 g/l, preferably 20-50 g/l of a polymerization product based on acrylamide to support the dyestuff diffusion in order to achieve an improved dyestuff penetration of the goods.


For the best possible thorough dyeing, the process and the liquor recipe were optimized for the highest possible dyestuff diffusion.


The invention is illustrated by the following dyeing samples:







EXAMPLE 1

Linen/cotton automotive upholstery fabric, about 430 g/m2, weaving sample 2 hereinabove described, desized, demineralized, bleached and mercerized, is padded in a semi-continuous cold pad batch process with the following recipe for a black dyeing

    • 45 g/l Reactive Orange CI RO 69
    • 25 g/l Reactive Rubinol CI RR 171
    • 70 g/l Reactive Blue CI RB 209
    • 50 g/l urea (solvent for dyestuff)
      • 1 ml/l nonionic wetting agent
      • 1 ml/l sequestration agent


An alkaline liquor of the following composition

    • 50 ml/l Sodium silicate 38° Bé
    • ml/l caustic soda 36 ° Bé


in liquor ratio of 1:4 is supplied continuously to the dye liquor by means of a dosage pump, and with this in the padder the fabric is padded. Liquor temperature: 20° C.


After this process, the fabric is batched cold 4 hours and washed off as follows:


It is rinsed in cold soft water, soaped in boiling water containing 2 ml/l Ladipur™ RSK liquid detergent, rinsed in hot soft water, then in cold soft water, neutralized with acetic acid and dried.


This gives a deep, level and good dyed-through black dyeing with perfect heat light fastness (FAKRA 3 fold grade note 8 blue scale, Xenon note 8 blue scale) and good wet fastness properties.


EXAMPLE 2

Linen/cotton—automotive upholstery fabric, 320 g/m2, weaving sample 1 hereinabove described, desized, demineralized, bleached, mercerized is dyed in a newly-developed, fully continuous E-control process of the textile machine company A. Monforts, Mönchengladbach, using the following recipe:

    • 45 g/l Reactive Orange CI RO 69
    • 25 g/l Reactive Rubinol CI RR 171
    • 70 g/l Reactive Blue CI RB 209
    • 100 g/l urea
    • 1 ml/l wetting agent (nonionic)


An alkali liquor containing 24 g/l soda ash in liquor ratio 1:4 with liquor temperature at 20° C. is separately led to the dyeing padder by means of a dosage pump.


The fabric is dyed at the E-control unit consisting of an IR pre-dryer and a hot-flue constant air humidity of 25% and 75% air and a chamber temperature of 125° C. (fabric temperature is approx. 69° C.).


The whole process consists of the steps of: padding, predrying at IR pre-dryer and complete drying at hot-flue. The complete dyestuff fixation takes place at the same time.


Afterwards the dyed fabric is washed off as follows:

    • Cold rinsing in soft water
    • In boiling soft water soaping with 2 ml/l Ladipur™ RSK liquid detergent
    • hot rinsing in soft water
    • cold rinsing in soft water
    • neutralization with acetic acid
    • drying


This gives a deep, level and good through-dyed black dyeing with perfect light fastnesses (FAKRA heat light fastness 3 fold, note 8 in blue scale, note 4.5 in grey scale, XENON perfect as well, note 8 in blue scale) and another good wet- and rubbing fastness.


EXAMPLE 3

Linen/cotton—automotive upholstery fabric, 320 g/m2, weaving fabric 1 as hereinabove described, desized, demineralized, bleached, mercerized, is dyed in a semi-continuous cold pad batch process using the following recipe:

    • 3.9 g/l Reactive Orange CI RO 69
    • 2.8 g/l Reactive Rubinol CI RR 171
    • 5.0 g/l Reactive Blue CI RB 209
    • 1 ml/l nonionic wetting agent
    • 1 ml/l sequestration agent


An alkali liquor in liquor ratio 1:4 of the following recipe

    • 50 ml/l sodium silicate 38° Bé
    • 5 ml/l caustic soda 36° Bé


is separately added by means of a dosage pump.


Dye liquor temperature: 20° C.


The dyed fabric is then batched cold for 4 hours and washed off as follows:

    • cold rinsing in soft water
    • boiled soft water soaping with 2 ml/l Ladipur™ RSK liq. detergent
    • hot rinsing in soft water
    • cold rinsing in soft water
    • neutralization with acetic acid
    • drying


This gives a level, good through-dyed light grey dyeing with very good wet- and rubbing fastnesses and a good XENON light fastness with note 6.5 in blue scale. The multiple FAKRA heat light fastness is good, but not quite so high a standard as achieved in the black dyeings hereinabove exemplified.


EXAMPLE 4

Linen/cotton—automotive upholstery fabric, 320 g/m2, weaving sample 1 hereinabove described, desized, demineralized, bleached and mercerized is dyed in the Monforts equipment of Example 2, using the following recipe:

    • 3.9 g/l Reactive Orange CI RO 69
    • 2.8 g/l Reactive Rubinol CI RR 171
    • 5.0 g/l Reactive Blue CI RB 209
    • 1.0 ml/l wetting agent (nonionic)


An alkaline liquor with 14 g/l soda ash in a liquor ratio of 1:4, liquor temperature: 20° C., is separately led to the dyeing trough by means of a dosage pump.


The fabric is dyed at the E-control unit consisting of IR pre-dryer and hot-flue constantly with a climate of 25% humidity and 75% air and a chamber temperature of 125° C. (fabric temperature is approximately 69° C.)


The whole continuous process is as follows: padding, pre-drying at IR pre-dryer and complete drying at hot-flue, and the dyestuff fixation takes place at the same time.


The dyed fabric is then washed off as follows:

    • cold rinsing in soft water
    • in boiling soft water soaping with 2 ml detergent from type Ladipur™ RSK liq. detergent
    • hot rinsing in soft water
    • cold rinsing in soft water
    • neutralization with acetic acid
    • drying


The result is a deep, level and good through-dyed light grey dyeing with very good wet- and rubbing fastnesses, with a XENON light fastness note 6.5 in blue scale, and a high-standard multiple FAKRA heat light fastness although not quite to the standard of the black dyeing hereinabove exemplified.


EXAMPLE 5

Linen/cotton 50/50, 430 g/m2 (weaving sample 4 hereinabove described) bleached and high twisted as black dyeing is dyed in a cold pad batch process. This new pattern is woven with in exhaust process-bleached, high twisted yarns. As a result, the fabric could withstand 60,000 rpm on the Martindale abrasion test.


EXAMPLE 6

Fabric: 100% linen, about 120 g/m2, bleached.


Continuous dyeing process compared: cold pad batch process against E-control process Monforts


Recipe Cold Pad Batch process:

    • 32 g/l Reactive Orange CI RO 69
    • 50 ml/l sodium silicate 38° Bé
    • 15 ml/l caustic soda 36° Bé
    • Batching time: 8 hours, followed by washing off and drying


Recipe E-control process:

    • 32 g/l Reactive Orange CI RO 69
    • 10 g/l soda ash
    • 2.5 ml/l caustic soda 36° Bé


The fabric is dyed at the E-control unit as hereinabove described, consisting of padder, infra-red pre-dryer and hot-flue unit with a constant climate of 25% humidity and 75% air and a chamber temperature of 125° C. (fabric temperature is approximately 69° C.). This results in doing so in the simultaneous achievement of pre-drying, complete drying dyestuff fixation, after padding. The dyed fabric is then washed oft as hereinabove exemplified.


Both processes give perfect, even deep and brilliant pure linen dyeing, in which the depth of dyeing is virtually identical.


In a further trial of the same methods and conditions on 100% linen of the same fabric with a deep navy shade with 90 g/l dyestuff, two perfect, even deep and brilliant pure linen dyeings are obtained. In this case, the dyeing of the E-control process was 13% deeper.


Finishing Process

For finishing, the now mercerized and dyed upholstery fabric product of linen/cotton must be made to meet the existing requirement profiles of the automobile and aircraft industry in three steps, as follows:

    • 1.) Mildew- and mold protection (microbacterial protection).
    • 2.) Flame resistance
    • 3.) Abrasion- and scour resistance
    • 4.) Antipilling
    • 5.) Stain resistance


The steps 1), 2) and 3) are carried out in that order, with the option of combining steps 2) and 3).


Finishing Example Step 1 (Microbacterial Protection)

The rotting and mold resistance finishing is done in a separate process with a bactericide of the type Sanitize™ 2724 (ex Sanitized AG, Switzerland) which is a pyrithione zinc compound at a treatment concentration of 0.5-2% based on the fabric weight. The application is carried out by padding or spraying, followed by drying at 100-150° C. The treatment takes place directly after the dyeing and drying processes. Because this is a pure natural product, rotting and mold resistance finishing is essential.


Finishing Example Step 2 (Flame Retardant Finishing)

The flame retardant finishing is achieved, using phosphate- or silicone products, preferably phosphate products.


Use concentration: 100 up to max. 500 g/l, preferably 200-300 g/l


The liquor is padded on and subsequently dried at 100-150° C.The treatment is carried out separately after the application of the anti-bacterial product, or it may optionally be combined with the abrasion resistance finishing of step 3). By optimization of the products and their concentrations , the good dry and wet rubbing fastnesses of the reactive dyeing are not impaired.


Finishing Example Step 3

Recipe: 100 g/l polyacrylate-based development product

    • 5 g/l fluorocarbon product (nonionic)
    • 0.3 g/l wetting agent (anionic)
    • The addition of softener products is also possible.


Padder application, wet pick up 80%, 1 min at 150° C. effectively dried and condensed.


The abrasion resistance of the black dyed sample was tested in the Martindale test method according to EN ISO 12947-1 with 12 Kpa at 5,000, 10,000, 20,000 and 60,000 RPM.


The 100% natural automotive upholstery sample could withstand undamaged the test up to 60,000 RPM.


The surprising aspect of the entire finishing operation is that the physiological and fastness results obtained after dyeing and drying, primarily the FAKRA and xenon light fastnesses, the rubbing fastness and the abrasion resistance according to the Martindale tests were not impaired but improved, so that the end-product meets the high requirements of the automobile, bus and aircraft industry. Moreover, this can be done with a natural product in place of a petroleum-derived synthetic product.


Combined Advantages of the New Invention

1.) An automotive and aircraft seat upholstery fabric consisting of pure vegetable natural products that meets the high physiological, fastness and safety related requirements of the aircraft and automobile industry.


2.) The product is 100% biodegradable and therefore is highly environmentally friendly.


3.) It consist of 100% natural renewable raw materials with high sustainability.


4.) The CO2 costs for the production of this natural product, calculated according to the cumulative energy demand (CED), is 83% lower than that of the production of petroleum-derived products or glass fibres.


5.) The fabric price is unaffected by the price fluctuations of the world petroleum market, and is thus stable and predictable.


6.) Physiological benefits of pure natural fibers.


7.) Car seat fibres build up no electrostatic charge.

Claims
  • 1.-12. (canceled)
  • 13. An automotive seat upholstery fabric or aircraft seat upholstery fabric made substantially from renewable and environmental-friendly natural fiber material wherein the said fabric contains at least about 50% by weight of the said upholstery fabric is linen.
  • 14. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric consists of linen and cellulose fibers selected from the group consisting of: cotton, bamboo and/or viscose.
  • 15. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 14, wherein the said fabric consists of at least about 50% by weigh of linen, and the fabric further consists of one or more further fibers selected from the group consisting of cotton, bamboo and/or viscose, and further wherein cotton and/or bamboo is present in an amount of between about 0% by weight and about 50% by weight and in which the viscose is present in an amount of between about 0% by weight and about 50% by weight.
  • 16. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein the said fabric consists of 50% by weight linen and about 10% by weight to about 50% by weight cotton and about 4% by weight to about 20% by weight of viscose.
  • 17. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein the said fabric has a weight of between about 100 and about 700 g/m2.
  • 18. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein the said fabric is washed, desized, demineralized, bleached and mercerized.
  • 19. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein the said fabric is formed by a process wherein it is semi- or fully continuously dyed in pieces, or is discontinuously dyed by exhaustion dyeing as yarn or pieces.
  • 20. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 19, therein the said fabric is a dyed fabric which has been dyed with high lightfast mono- or multifunctional reactive dyestuffs.
  • 21. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 19, characterized in that the fabric is dyed with a dye liquor in which is present 10-60 g/l of an acrylamide-based polymerization product which improves the through-dyeing or the dyestuff diffusion.
  • 22. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 21, characterized in that the said fabric it is padded with an additional finishing liquor containing 50-200 g/l of a polyacrylate, 2-15 g/l of a fluorocarbon product (non-ionic) and from 0.2-2 g/l anionic wetting agent and optionally further padded with a softener product, and wherein the padded fabric is subsequently dried for 1 min at 150° C. and fixed.
  • 23. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, characterized in that this fabric is padded or sprayed with a bactericide against decay and mold and is thereafter dried.
  • 24. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric is finished with a flame-resistant finishing based on a phosphate compound which impairs neither the light fastness (FAKRA) nor the rubbing fastness of the finished fabric.
  • 25. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric has a weight of between 200 and 600 g/m2.
  • 26. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric which exhibits a Martindale test score according to EN ISO 12947-1 with 12 Kpa of at least 50,000 rpm.
  • 27. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 26, wherein said fabric exhibits a Martindale abrasion test score of at least 60,000 rpm.
  • 28. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric is treated with a bactericidal composition which imparts resistance to mold.
  • 29. An automotive seat upholstery or aircraft seat upholstery fabric according to claim 13, wherein said fabric is treated with a bactericidal composition which improves the rot resistance of the said fabric.
Priority Claims (1)
Number Date Country Kind
202010007668.4 Jun 2010 DE national
Continuations (1)
Number Date Country
Parent 13702762 Feb 2013 US
Child 14688601 US