Patent Application
20130067629
The invention relates to fabrics, and especially cellulosic fabrics that comprise a treatment to render the fabric fast drying and methods to produce the same.
Fast drying fabrics comprising cellulosic yarns provide garment benefits in the areas of active sports, outdoor work, recreational activities, military and other uses for example, where the rate of perspiration is high. In some cases, fabric is treated with a water resistant chemical to a degree that the entire fabric becomes water resistant or hydrophobic. In other cases, a blend of cellulosic and synthetic yarns is incorporated into the fabric to provide improved water resistance and in some configurations, more rapid drying rates. These fabrics however, do not have the appearance, ability to wick quickly, or comfortable feel of untreated cellulosic fabrics. In addition, these fabrics are typically treated with a hydrophobic chemical, or are blended with a synthetic fiber or hydrophobic treated yarn that does not absorb water, which reduces the overall ability of the fabric to absorb water compared to an untreated fabric. These fabrics therefore, do not absorb water to the degree of an untreated cellulosic fabric. Therefore, these fabrics do not sufficiently absorb water and are not well suited for drying applications, such as towels, for example.
Thus, there exists a need for a fabric that has the appearance and feel of untreated cellulosic fabric, has a water weight gain similar to an untreated cellulosic fabric, is hydrophilic to provide wicking of sweat and is fast drying. The invention is directed to these, as well as other, important needs.
The invention is directed to a fabric comprising a treatment that renders the fabric fast drying and hydrophilic. The treatment comprises a chemically bonded treatment portion and a physically attached hydrophobic particle treatment portion. The treatment is applied in such low concentrations that the fabric remains hydrophilic and retains the look and feel of the untreated base fabric. The unique combination of the two treatment portions in the range of concentration described herein, surprising renders fabric fast drying, while not substantially changing the water weight gain performance from that of the base, untreated fabric. In one embodiment the fabric comprises a cellulosic material, and in another embodiment the fabric consists essentially of a cellulosic material, such as cotton.
Accordingly, in one embodiment, the invention is directed to articles of manufacture, comprising:
In another embodiment, the invention is also directed to processes for producing an article, comprising:
In further embodiments, the invention is directed to compositions, comprising:
The hydrophobic particle treatment portion comprises hydrophobic particles such as fluoropolymer particles, including but not limited to polytetrafluoroethylene (PTFE). The hydrophobic particle may be very small, such as less than about 10 μm, preferably, less than about 10 μm, and more preferably, less than about 500 nm. In addition, the particles may comprise high molecular weight fluoropolymer, such as PTFE, that are relatively deformable and in some embodiments may fibrillate when sheared. The particles are physically attached to the fiber and/or trapped in the yarns and in the fabric through a treatment process including in some embodiments a squeezing or padding process step whereby the fabric is compressed after being treated with the hydrophobic particles.
The chemically bonded portion described herein is chemically bonded to the hydroxyl groups of the cellulosic material. The chemically bonded portion may comprise a hydrophilic portion and/or hydrophobic portion. The chemically bonded portion may be a linear compound or polymer. The relatively low amount of chemically bonded treatment portion provides for more effective water release, and faster drying times. The hydrophobic portion of the chemically bonded treatment portion may comprise a fluorine group, or fluoropolymer, and the bonding portion may comprise a urethane or an acid, or any other reactive site that will bind or chemically react to the hydroxyl groups of the fabric surface. The chemically bonded portion may be bonded to the fabric with the aid of a catalyst, such as but not limited to metal salts (such as, for example magnesium chloride, potassium chloride, antimony salt, or a combination thereof).
The cellulosic fabric described herein may be a knit, woven or non-woven and may be any suitable weight, or comprise any suitable denier or count of yarn. For example, the base fabric may consist essentially of a cotton yarn in a woven, knit, or nonwoven structure. In another embodiment, the fabric may consist essentially of cellulose, or cellulosic derivatives, such as cotton, fire-resistant cotton, viscose, linen, rayon, fire-resistant rayon, lyocell, or any combination thereof. The fabric may comprise a substantial amount of cellulosic material, that is, the fabric comprises at least 45% by weight cellulosic material. The fabric may comprise any weight percentage of cellulosic material above 45%, such as more than about 50%, more than about 60%, more than about 65%, or more than about 75%. In one embodiment, the fabric comprises about 50% by weight polyester and about 50% by weight cotton, or some other cellulosic material. In another embodiment the fabric is comprised of about 35% by weight polyester and about 65% by weight cotton, or some other cellulosic material. The fabric described herein may consist essentially of cellulose material or cellulosic derivative. For example, the yarns of the fabric may consist essentially of cellulose material or cellulosic derivatives, wherein the base fabric, excluding the treatment described herein or any other softeners or treatments, is made of only cellulosic material, such as cotton. In yet another embodiment, the fabric comprises yarns that have a blend of a cellulosic derivative material, or fiber, and a non-cellulosic material or fiber, such as a synthetic or polymeric fiber such as polyester.
The article described herein may be in the form of a garment, such as a shirt, pants, and especially an active wear garment, where fast drying of perspiration is beneficial. The article described herein may also be in the form of an undergarment, such as socks or underwear. The article may also be in the form of a drying or washing article, such as a towel or washcloth, or cleaning, or drying article. The article described herein may comprise fabric described herein or may be made essentially of the fabric described herein.
Typically, hot environments and intense activities are associated with higher outputs of sweat production. Fabrics that wick and have high water release rates will be better able to keep up with increased sweat production and will not become over saturated. In addition, once the wearer stops the activity, a fabric saturated with sweat begins to rob heat from the body causing chills as the environment cools. Even slightly higher water release rates (WRR) have an impact on comfort, as these are time-based measurements whose benefits accumulate over time. Fabrics with higher WRR and wicking help to remove body heat containing sweat from the skin, which can help to reduce core temperature. High WRR fabrics enable garments made from that fabric to dry quickly and restore the fabrics ability to provide dry insulation when sweat-producing activities cease.
The fabric described herein may be produced by a method that utilizes greige or dyed base fabrics consisting essentially of cellulosic yarns or fibers, and a treatment process that can be integrated into existing fabric producing or fabric finishing processes. In one embodiment, the method described herein is relatively low cost and an easily integrated process that can be implemented in line on many standard fabric finishing processes. In addition, the method described herein does not require the use of specially finished fiber or yarns. In addition, a dye and/or fabric softener may be applied to the fabric before, after, or during the treatment process described herein. The treatment process described herein comprises at least one treatment step, where the hydrophobic particles and/or chemically bonded treatment portion are applied to the fabric. This treatment step is followed by a drying step, and in some cases an additional heating step. A heating step may be used to provide energy necessary for chemically bonding the chemically bonded treatment portion with the hydroxyl groups on the base fabric. The two treatment portions may be applied in any suitable manner and may be applied in separate steps to the fabric or to yarns of the fabric. The treated fabric may be passed through a compression process, such as a nip rollers, or belts, where a portion of the treatment formulation is squeezed out of the fabric. The fabric may then be subjected to elevated temperatures in any conventional way to drive off any treatment formulation or excess liquid, or water. The heat treatment process may be used such as a conventional oven or tunnel dryer.
The summary is provided as a general introduction to some of the embodiments of the invention, and is not intended to be limiting. Additional example embodiments, including variations and alternative configurations of the invention as well as combinations of embodiments are provided herein.
The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
As employed above and throughout the disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings.
As used herein, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly indicates otherwise.
The use of numerical values in the various quantitative values specified in this application, unless expressly indicated otherwise, are stated as approximations as though the minimum and maximum values within the stated ranges were both preceded by the word “about.” In this manner, slight variations from a stated value can be used to achieve substantially the same results as the stated value. Also, the disclosure of ranges is intended as a continuous range including every value between the minimum and maximum values recited as well as any ranges that can be formed by such values. Also disclosed herein are any and all ratios (and ranges of any such ratios) that can be formed by dividing a recited numeric value into any other recited numeric value. Accordingly, the skilled person will appreciate that many such ratios, ranges, and ranges of ratios can be unambiguously derived from the numerical values presented herein and in all instances such ratios, ranges, and ranges of ratios represent various embodiments of the present invention.
As used herein, the term “physical bond” refers to a mechanical connection or contacting, interference, filtration trapping, or secondary chemical bond (like van der Waals forces, hydrogen bonding, or where attraction exists between the particle and a surface but where no electron sharing or transfer occurs).
As used herein, the term “chemical bond” refers to a bond that holds the chemically bonded treatment portion durably to the fabric surface. A typical example is a primary bond formed from the reaction of a urethane or an acid, for example, and a hydroxyl (—OH group) naturally present in cellulosic materials, such as cotton. Other examples include an acid reaction or a hydration reaction of a double bond.
As used herein, the term “treatment” refers to a combination of a hydrophobic particle treatment portion and a chemically bonded treatment portion as described herein.
As used herein with reference to an article of manufacture, the term “hydrophilic” as used herein in reference to the article of manufacture of the invention, refers to an article that has a horizontal wicking time of no more than about 8 seconds, preferably no more than about 5 seconds, and even more preferably no more than about 3 seconds.
As used herein with reference to an article of manufacture, the term “fast drying” refers to an article having a comfort zone dry time at least about 10% faster than a control article. The article described herein may have a single or an average comfort zone dry time at least about 10% faster, preferably about 15%, even more preferably about 30%, yet more preferably about 50% or even further more preferably about 65% faster than a control article. A “control article” is an article having substantially the same construction and composition as the treated article described herein without the treatment described herein. This may be expressed using the following equation:
As used herein, the term “total dry time” refers to the time an article takes to dry from full saturation (article is submerged in water and padded with AATCC padding paper) to a saturation of 2% water content.
As used herein, the term “comfort dry time” refers to the time an article takes to dry from 20% by weight water content to 2% by weight water content. This 20% water content was based upon subjective testing and serves as a more realistic “wetness” level in garments exposed to sweat than full saturation.
As used herein, the term “water release rate” (WRR) refers to the percentage of water released from the fabric per minute in a controlled environment using a modified version of the provisional AATCC Gravimetric Drying Test Method (AATCC/MM TS-05) using multiple scales and multiple sample measurements for better accuracy of sample weights.
As used herein, the term “comfort score” refers to a performance score that quantifies ability of an article to absorb water and dry rapidly. The comfort score is the ratio of the water weight gain percent over the comfort zone dry time in minutes. The average comfort score reported herein is the average calculated for the fabrics before washing.
As used herein, the term “garment,” as used herein, refers to any article of clothing or clothing accessory worn by a person, including, but not limited to shirt, pants, underwear, outer wear, footwear, headwear, swimwear, workwear, uniforms, belts, gloves, socks, headbands, wristbands, sports specific activity apparel such as karate uniforms, and especially those used as protective wear or gear.
As used herein, the term “linen,” as used herein refers to any article of fabric or material used on a bed or similar furniture, including, but not limited to a sheet, pillowcase, blanket, throw, afghan, sleeping bag, baby bunting, quilt, comforter, mattress cover, and the like.
While the present invention is capable of being embodied in various forms, the description below of several embodiments is made with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiments illustrated. Headings are provided for convenience only and are not to be construed to limit the invention in any manner. Embodiments illustrated under any heading may be combined with embodiments illustrated under any other heading.
The fabric described herein comprises a treatment that renders the fabric fast drying and hydrophilic. The fabric 100 shown in
In one embodiment, the fabric described herein is hydrophilic, as defined by a fabric having a horizontal wicking time of no more than about 8 seconds. The hydrophilic fabric described herein may have a horizontal wicking time of no more than 5 seconds or no more than 3 seconds. The yarns of a knit fabric, warp or weft yarns of a woven fabric, or any yarns or fibers (if the fabric is made from a single compositional yarn), may be removed from a fabric and tested for horizontal wicking according to the test method described herein. In one embodiment, the fabric described herein is comprised essentially of yarns that are hydrophilic as defined herein.
As shown in
The treatment process may comprise mixing both the hydrophobic particle treatment portion and the chemically bonded treatment portion into a single treatment whereby the fabric may be coated, such as by dipping, spraying, soaking or any other suitable means. The treatment portions may also be applied separately, and the chemically bonded treatment portion may be applied and reacted before the hydrophobic particle treatment portion is applied, for example. In one embodiment both treatment portions are combined into one treatment bath and the fabric may be submerged in the bath, squeezed to remove any excess liquid, and then dried. The drying may cause the chemically bonded treatment portion to react with the fabric, or a separate heating step may be used to bond the chemically bonded treatment portion.
The treatment as described herein may be applied uniformly to the fabric. For example, the treatment may be applied to the entire fabric, such as through a dipping process. The hydrophobic particle treatment portion and chemically bonded treatment portion may be uniformly distributed throughout the fabric, and may not be substantially concentrated on one side of the fabric. As used herein, the term “uniformly distributed” in reference to the treatment, means that both the hydrophobic particle treatment portion and chemically bonded treatment portion are substantially uniformly distributed throughout the fabric and not concentrated or applied in such a way to produce a gradient in concentration, over the surface of the fabric or through the fabric. In another embodiment however, the treatment may be applied in such a way to produce a gradient of concentration from one side of the fabric to the other side.
Any suitable fabric may be treated with the hydrophobic particle treatment portion and chemically bonded treatment portion as described herein. In one embodiment, the fabric comprises cellulosic materials such as cellulose or cellulosic derivative materials including cotton, fire-resistant cotton, viscose, linen, rayon, fire-resistant rayon, lyocell, or a combination thereof. The fabric may comprise a substantial amount of cellulosic material, wherein the fabric comprises at least 45% by weight cellulosic material. The fabric may comprise any weight percentage of cellulosic material above 45%, such as more than about 50%, more than about 60%, more than about 65%, or more than about 75%. In one embodiment, the fabric is comprised of about 50% by weight polyester and about 50% by weight cotton, or some other cellulosic material. In another embodiment the fabric comprises about 35% by weight polyester and about 65% by weight cotton, or some other cellulosic material. The fabric described herein may consist essentially of cellulose or cellulosic derivative. For example, the yarns of the fabric may consist essentially of cellulose or cellulosic derivatives, wherein the base fabric, excluding the treatment described herein or any other softeners or treatments, is made of only cellulosic material, such as cotton. In one embodiment, the fabric is a knit consisting essentially of cotton yarns. Dyes or softeners within the fabric may be used in embodiments where the fabric consists essentially of cellulose or cellulosic derivative. In another embodiment, the fabric is woven comprising warp and weft yarns where the warp yarns consist of cotton and the weft yarns consists of lyocell. Any combination of yarn weights or cellulosic types may be incorporated into a fabric that, for the purposes of this invention, consists essentially of cellulosic material. In some embodiments, the treatment is applied to a uniform fabric, where the fabric consists of a single composition of yarn. For example, a woven fabric consisting of cotton yarns only, would be considered a uniform fabric.
The hydrophobic particle treatment portion may be any suitable hydrophobic particle and may comprise a polymer. Hydrophobic particles may comprise any suitable materials including but not limited to polymers, metals, glass, ceramic, and the like. In addition, combinations of materials may be used as the hydrophobic particles described herein. For example, a rigid hydrophobic polymer or material, such as silica may be entrained or otherwise incorporated into a softer polymeric material. In one embodiment, the hydrophobic particles consist essentially of a polymer, such as a fluoropolymer. In another embodiment, the particles consist of a fluoropolymer, such as PTFE. The PTFE may be a high molecular weight PTFE, such as a PTFE dispersion. The dispersion may be of a fine powder type PTFE, having a molecular weight of more than 100,000. PTFE is a chemically inert polymer and therefore does not chemically react with the fabric and is not chemically bonded to the fabric. However, PTFE especially high molecular weight, fine powder type PTFE, is known to fibrillate when sheared and is of a size that can be trapped and therefore may physically bond to a surface.
The hydrophobic particles of the hydrophobic particle treatment portion may have any suitable particle size such as no more than about 10 μm, no more than about 1 μm, no more than about 500 nm, no more than 100 nm, or any range between the specific values provided. The particle size and void fraction of the polymeric particles may be determined by conventional techniques known, including microscopy and the Brookhaven Model BI-90 Particle Sizer supplied by Brookhaven Instruments Corporation, Holtsville, N.Y., which employs a quasi-elastic light scattering technique to measure the size of the particles. The molecular weights of the polymers may be from about 100,000 to 5 million weight average, and most preferably, above 500,000.
The chemically bonded portion is chemically bonded to the hydroxyl groups of the cellulosic fabric and may comprise a hydrophilic portion and/or hydrophobic portion. The chemically bonded portion may be a linear compound or polymer. The relatively low amount of chemically bonded treatment portion provides for more effective water release, and faster drying times. The hydrophobic portion of the chemically bonded treatment portion may comprise a fluorine group, or fluoropolymer, and the bonding portion may comprise a urethane or acid, or any other reactive site that will bind or chemically react to the hydroxyl groups of the fabric surface. The chemically bonded portion may be bonded to the fabric with the aid of a catalyst, including but not limited to metal salts (such as, for example, magnesium chloride, potassium chloride, antimony salts, or a combination thereof.
In certain embodiments, the chemically bonded treatment portion is formed from a mixture comprising:
at least one hydrophilic polymer having a moiety reactive with a hydroxyl group on said cellulosic material; and
at least one hydrophobic fluoropolymer.
RAINOFF® SRL-1, available from Eastern Chemical Co. Providence, R.I., is an example of a suitable mixture for use in the articles of manufacture, processes, and compositions of the invention. Other examples include, but are not limited to, similar chemistries such as Unidyne 991, 992, and 993 available from Daikin, Zonyl 7910, 9815, 9933, and 9938 available from DuPont, Nanotex 603B and 604B, Repearl SR-1100 available from Mitsubishi, FC258 and PM490 available from 3M, NUVA SRL from Clariant, Baygard SOC and Baygard WSR from Bayer, Oleophobol ZSR from Ciba, and the like.
In certain embodiments, the hydrophilic polymer having a moiety reactive with a hydroxyl group on said cellulosic material is present at a level of about 10% by weight to about 90% by weight, based on the total weight of said mixture. In certain embodiments, the hydrophilic polymer having a moiety reactive with a hydroxyl group on said cellulosic material is present at a level of about 40% by weight to about 70% by weight, based on the total weight of said mixture. In certain embodiments, the hydrophilic polymer having a moiety reactive with a hydroxyl group on said cellulosic material is present at a level of about 70% by weight to about 90% by weight, based on the total weight of said mixture.
In certain embodiments, the hydrophobic fluoropolymer is present at a level of about 10% by weight to about 90% by weight, based on the total weight of said mixture. In certain embodiments, the hydrophobic fluoropolymer is present at a level of about 10% by weight to about 40% by weight, based on the total weight of said mixture. In certain embodiments, the hydrophobic fluoropolymer is present at a level of about 10% by weight to about 30% by weight, based on the total weight of said mixture. In certain embodiments, the hydrophobic fluoropolymer has a degree of polymerization of about 2 to about 10, preferably, about 2 to about 5.
In certain embodiments, the chemically bonded treatment portion has a fluorine content of about 0.01% by weight to about 1% by weight, based on the total weight of said chemically bonded treatment portion.
In certain embodiments, the hydrophilic polymer is formed from at least one monomer selected from the group consisting of vinyl acetate, substituted vinyl acetate, C1-C6 alkyl(meth)acrylate, substituted C1-C6 alkyl(meth)acrylate, and combinations thereof. In certain embodiments, the hydrophilic polymer is ethylene-vinyl acetate.
In certain embodiments, the hydrophobic fluoropolymer has a degree of polymerization of about 2 to about 10. In certain embodiments, the hydrophobic fluoropolymer has a degree of polymerization of about 2 to about 5.
In certain embodiments, the hydrophobic fluoropolymer comprises residues of at least one C6-C16 fluorine-containing monomer, or a linear or branched congener thereof. In certain embodiments, the hydrophobic fluoropolymer comprises residues of at least one C6-C16 perfluoroalkyl-containing monomer, or a linear or branched congener thereof. In certain embodiments, the hydrophobic fluoropolymer further comprises residues selected from the group consisting of C6-C16 perfluoroalkyl-containing vinyl alcohol, C6-C16 perfluoroalkyl-containing (meth)acrylate, and combinations thereof.
In certain embodiments, the chemically bonded treatment portion comprises at least one compound
having a moiety reactive with a hydroxyl group on said cellulosic material and;
having a hydrophobic organofluorine moiety.
In certain embodiments, the moiety reactive with a hydroxyl group comprises a residue of at least one monomeric unit selected from the group consisting of vinyl acetate, substituted vinyl acetate, C1-C6 alkyl(meth)acrylate, substituted C1-C6 alkyl(meth)acrylate, and combinations thereof. In certain embodiments, the hydrophobic organofluorine moiety comprises a residue of at least one monomeric unit selected from the group consisting of C6-C16 perfluoroalkyl-containing monomers, and combinations thereof.
The article described herein may be in the form of a garment, such as a shirt, pants, and especially an active wear garment, where fast drying of perspiration is beneficial. The article described herein may also be in the form of an undergarment, such as socks or underwear. The article may also be in the form of linen, such a bedding, sheets, blankets, and the like, or a drying or washing article, such as a towel or washcloth, or cleaning, or drying article. The article may comprise fabric as described herein, or may be made essentially of the fabric described herein.
In some embodiments, the fabric described herein may comprise additional materials, such as a coating or treatment, or fibers or yarns for additional functionality, such as an antimicrobial agent, an odor control agent, an odor absorbing agent, an antistatic agent, a ultraviolent finish, a wrinkle resistance agent, an insect repellent, fabric sun protection, and a combination thereof. In one embodiment, the fabric described herein comprises no more than about 10% by weight odor control material, such as a coating, treatment, fiber, or yarns. In another embodiment, the fabric described herein comprises no more than about 15% by weight stretch fibers, filaments, or yarns. In yet another embodiment, the fabric described herein comprises no more than about 15% by weight structural fibers, filaments or yarns such as nylon for improved abrasion resistance and structural integrity. In still another embodiment, the fabric described herein comprises no more than about 7% by weight static control, or antistatic material, such as a coating, treatment, fiber, filament or yarn. In still another embodiment, the fabric described herein comprises no more than about 7% by weight antimicrobial material, such as a coating, treatment, fiber, filament, or yarn. Antimicrobial material may include siloxane, silver containing materials or compounds, or quaternary ammonium, for example.
The present invention is further defined in the following Examples, in which all parts and percentages are by weight, unless otherwise stated. It should be understood that these examples, while indicating preferred embodiments of the invention, are given by way of illustration only and are not to be construed as limiting in any manner. From the above discussion and these examples, one skilled in the art can ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions.
The sample sheets tested herein were tested prior to washing, after 10, 20, and 30 wash cycles. When an average value is reported herein, it is the average of the prewash value, and the values measured or calculated after the 10, 20 and 30 was cycles.
The initial weight of the fabric was measured after remaining in a conditioned environment for at least 12 hours, but before the fabric was submerged in water, sandwiched between AATCC blotting paper, and passed through a padding roll with at 0.05 MPa pressure. The initial weight before submersion and the weight after the padding step were used to calculate Water Weight Gain in percent where:
Fabric was tested in accordance with a modified version of the provisional AATCC Gravimetric Drying Test Method (AATCC/MM TS-05) using multiple scales and multiple sample measurements for better accuracy of sample weights.
The Comfort WRR was measured in accordance with a modified version of the provisional AATCC Gravimetric Drying Test Method (AATCC/MM TS-05) using multiple scales and multiple sample measurements for better accuracy of sample weights.
Horizontal wicking time of materials made according to the present invention as well as comparative materials and control materials were measured according to Absorbency of Textile (Test Method AATCC 79 Absorbency of Textile). Horizontal wicking may be performed on a fabric or on yarns of a fabric as described in the test method.
Dry Time of materials made according to the present invention as well as comparative materials and control materials may be tested in accordance with:
Modified version of the provisional AATCC Gravimetric Drying Test Method (AATCC/MM TS-05);
Durability testing—wash cycles as described in AATCC 135 versus WRR.
Differential Scanning calorimetry—modified test protocol used to determine energy required to dry water from fabrics at body temperature (37° C.)
IR or ATC
A uniform fabric was treated with a treatment as described herein. A 4.8 oz/sq yd jersey knit fabric available from Swisstex, Los Angeles, Calif., was cut into about 20.3 cm by 40.6 cm sheets. One sheet was designated as a control and the other samples were treated with various concentrations of the treatment. All of the sheet were placed into a conditioned environment of 70F/65% RH for 12 hours and then individually weighed. The control sheet was saturated with water and subsequently passed through a padder. The control sample was weighed and the water weight gain was calculated. The nip pressure was adjusted as necessary, until a control sheet had a water weight gain of 65% to 70%. The pressure level in the nip of the padder was about 0.4 to 0.6 MPa, which was sufficient to remove any excess water not able to be absorbed completely into the fabric, yarn, and fibers. The nip pressure was then fixed for all subsequent treatments of the fabric.
A treatment formulation was prepared for Example 3 by combining in a glass beaker, water, a chemically bonded treatment portion, and a hydrophobic particle treatment portion. The chemically bonded treatment portion was RAINOFF® SRL-1, available from Eastern Chemical Co. Providence, R.I. Example 3 was prepared by adding 14.29 g of the chemically bonded treatment portion to 181.20 ml of water (see Example 3). The hydrophobic particle portion was a PTFE dispersion, DX9025 from Daikin America Inc. Orangeburg, N.Y. Approximately 0.94 g of the hydrophobic particle portion, having a percent solids of about 60% by weight solution, was added to the beaker of water containing the chemically bonded treatment portion. Approximately 3.57 g of magnesium chloride was added to the formulation. The formulation was mixed by a magnetic stirrer for approximately 10 to 12 minutes to create the treatment formulation. Other textile auxiliary finishes and/or additives may be added to the formulation such as, for example, softeners, antimicrobial agents, resins, binders, antistatic agents, and the like. In addition, other products may be substituted for the chemically bonded portion treatment in this example and many suppliers make equivalent hydrophobic particles.
Each sheet of fabric was submerged in the specific treatment formulation and then passed through the padder and the weight gain was calculated. The treated sample was then placed in a convection oven set to a temperature of 250° F. for approximately 4 minutes. The sample sheet was then removed from the oven and the oven temperature was increased to 300° F. When the oven reached 300° F., the sample sheet was placed back into the oven for approximately 2 minutes.
All samples were then conditioned in an environmentally controlled room overnight, where the relative humidity was approximately 65%, the temperature was approximately 70° F.
This process was repeated with chemically bonded treatment portion formulation of Examples 1, 2, and 4 containing 2%, 3.5% and 10% of chemically bonded portion respectively.
The control fabric sheet and all treated fabric sheets where tested per the test methods described herein.
The treatment process as described in the Cotton Knit example was followed to make the treated woven cotton samples. The woven cotton fabric used was a 2.9 oz/yd2 plain weave available from Jo-Ann Fabrics Inc. The control fabric sheet and all treated fabric sheets where tested per the test methods described herein.
The treatment process as described in the Cotton Knit example was followed to make the treated 50/50 polyester/cotton fabric samples. The 50/50 polyester/cotton fabric used was a 4.8 oz/yd2 plain jersey knit available from Swisstex. The control fabric sheet and all treated fabric sheets where tested per the test methods described herein.
The cotton knit fabric described in the Cotton Knit example was treated with a 5% concentration durable water repellant (DWR) finish—UNIDYNE TG 581, available from Daikin, Orangeburg, N.Y. A 5% solution of the DWR was created by adding 42.86 g, of the TG-581 to 547.14 ml of water. The sample sheet was submerged in the solution, padded to allow for at least about 70% by weight, based on the weight of the solution, and dried according to the cotton knit example procedure. The comparative fabric A sheet was tested per the test methods described herein.
The comparative example was prepared by cutting samples of transDRY™ fabric available from Cotton Incorporated, Cary, N.C.
The fabric described herein has a unique combination of properties that makes it well suited for applications where high rates of moisture wicking and drying are desired. The fabric described herein is hydrophilic and can absorb a high percentage of water, and is fast drying. As shown in
Table 1 shows that the treated samples as described herein could be made to have a horizontal wicking time of no more than 8 seconds. The comparative fabric A had a horizontal wicking time of more than 100 seconds and would not be considered to be hydrophilic as described herein.
Table 2 shows the performance measured for comparative fabric B. Comparative example B had lower comfort and total WRR rates than the treated knit fabrics described herein.
As shown in
As shown in
As shown in
The comfort score of a fabric is a measure of a fabric's ability to absorb water combined with the fabric's ability to dry quickly. The comfort score is the ratio of the water weight gain percent over the comfort zone dry time in minutes. The comfort score reported herein is calculated for the fabrics before washing. Table 3 shows calculated comfort score for the treated knit cotton fabrics described herein, the cotton knit control fabric, and the two comparative knit fabric samples. In addition, Table 3 shows the percent improvement in comfort score over the cotton knit control sample. The fabric sample of Example 3 had a 24.7% improvement in comfort score over the cotton knit control sample. The two comparative fabric samples A and B had much lower comfort scores than the control fabric.
The water weight gain of the woven cotton control fabric along with the fabrics made as described herein is provided in Table 4. As shown, the treated fabrics of Examples 2 and 3 had less than 5% less water weight gain than the woven cotton control. Both the comfort and total WRR were highest for the fabric sample of Example 3 as shown in
Table 5 shows the comfort score for the treated woven cotton fabrics described herein and the woven cotton control sample. In addition, Table 5 shows the percent improvement in comfort score over the woven cotton control sample. The fabric sample having a Example 2 had approximately a 16% improvement in comfort score over the control sample.
As shown in
Table 7 shows the comfort score for the treated 50/50 polyester/cotton fabrics described herein, and the 50/50 polyester/cotton control sample. In addition, Table 7 shows the percent improvement in comfort score over the control sample. The fabric sample having Example 3 had approximately a 47.9% improvement in comfort score over the control sample.
The fabric described herein may be fast drying as defined herein. The percent improvement in comfort zone dry time may be greater than 10%. As shown in Table 8, the treated knit fabric of Examples 1, 2, and 4 all had greater than a 10% improvement in the average comfort zone drying time over the cotton knit control fabric with a maximum observed value at the concentration of Example 3. The comparative fabric A has a greater than 10% improvement in drying time as well, however, this sample does not have as high of a water weight gain and does not wick. Comparative fabric B, had no improvement in average comfort zone drying time.
Table 9 shows that the Example 3 treated woven fabric described herein had a 14.3% improvement in comfort zone drying time over the woven control sample and would be considered fast drying as defined herein.
Table 10 shows that all of the treated 50/50 polyester/cotton fabric samples described herein had at least a 10% improvement in comfort zone dry time over the control, and would be considered fast drying as defined herein.
When ranges are used herein for physical properties, such as molecular weight, or chemical properties, such as chemical formulae, all combinations, and subcombinations of ranges specific embodiments therein are intended to be included.
The disclosures of each patent, patent application, and publication cited or described in this document are hereby incorporated herein by reference, in their entirety.
Those skilled in the art will appreciate that numerous changes and modifications can be made to the preferred embodiments of the invention and that such changes and modifications can be made without departing from the spirit of the invention. It is, therefore, intended that the appended claims cover all such equivalent variations as fall within the true spirit and scope of the invention.
This application claims the benefit of U.S. Application No. 61/536,825, filed Sep. 20, 2011, the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61536825 | Sep 2011 | US |
