METHOD AND PRODUCTS TO IMPART STAIN PROTECTION

RELATED APPLICATION

[0001] This application claims priority to German Application No. 102018126485.2, filed on October 24, 2018, which application is incorporated herein by reference in its entirety.

DESCRIPTION

[0002] The present invention relates to the field of stainblockers for carpets and/or fabrics.

[0003] In the industrial production of carpets or carpet tiles, it is common to treat such substrates with a composition to impart added desirable properties thereto, such as resistance to staining by a variety of agents, e.g. foods or beverages. For example, some especially troublesome stains are coffee, black tea and red wine.

[0004] Compositions referred to as“stainblockers” are commonly applied to carpets or carpet tiles made from PA66 or PA 6 to impart stain resistance. There is presently available both a continuous process and a discontinuous, or batch-wise, process for applying a stainblocker composition to a carpet. Recently one system is commercially available wherein a stainblocker composition is also topically applied to different dyeable carpets.

[0005] Furthermore the production of carpets and/or textile floor coverings usually includes the application of a soil- resist agent. These soil-resist agents are typically fluorocarbon compounds, although fluorine free-compounds have been suggested in the prior art.

[0006] So typically, after the application of the stainblocker, a soil resist agent is applied as the last step in carpet finishing prior to drying or backing. The required amounts of soil resist agent are between 1.0% and 1.6 weight% calculated on carpet weight. Common drying temperatures of 110-130°C are sufficient to allow the soil resist to completely cross-link onto the fibre. The widely used spray application is the simplest method of applying soil resist agents. A spray facility can be installed in front of a dryer after coloration or in front of a latex backing oven. An aqueous solution of soil resist agent is pumped through spray nozzles, installed above the running carpet, onto the carpet pile. For better distribution/penetration into the pile the solution should be applied to a wet, hydroextracted carpet. The wet pickup should be as low as possible, between 15-25%, calculated on carpet weight. The most advanced method for the treatment of carpets with soil resist agents is foam application. By using this minimum moisture application system, highly concentrated liquors in a foam state are applied to carpets running past, with a wet pickup of between 10% on wet carpets and 15% on dry carpets. A further advantage of the foam application method is its improved penetration. Foam application facilities can be installed in front of a dryer or a latex backing oven. To generate a fine uniform consistency it is sometimes necessary to add foaming agents. These chemicals are formulated in such a way that they decompose under common drying temperatures of 110-130°C and do not negatively impact the repellency performance of the soil resist agents.

[0007] ft is clear that the two-step process is time consuming and cost and resource intensive. That is why in recent proposals, the application of the stain repellent together with the soil- resist agent is advocated.

[0008] For example US2003/0204015 A1 reveals that a mixture containing among others a sulphonated condensation product of phenol and formaldehyde as stain repellent and fluorocarbons compounds can be applied to the fibers.

[0009] The application of stain repellent based on resole together with fluorinated, oil, water and/or soil repellent substances on a polyamide substrate is further known from US 5 447 755. [0010] There is, however, still a need for improved stain blocking and soil repellent compositions. Especially it has been found that in many applications there are stability problems when using mixtures of conventional stain blocking and soil repellent compositions, especially when the soil repellent compositions are fluorine-free, so that the task of the present invention is to provide an improved stain composition compared to the current state of technology.

[0011] The present invention, therefore pertains to a stainblocking composition comprising an aequeous solution of at least one stainblocking agent, whereby the aequous solution is alkaline.

[0012] The term“stainblocker” or“stainblocking agent” in the sense of the present invention especially means and/or include compounds which are able to associate with polymer amine end groups of a fabric and/or carpet to be blocked thus protecting such fabric and/or carpet from staining by (acidic) dye stains.

[0013] The term“alkaline” especially means that the aequous solution has a pH of >7.

[0014] Surprisingly it has been found that by using such a stainblocking composition for most applications many of the problems addressed above, especially the stability problems can be overcome.

[0015] It has been found advantageous for many applications of the present invention that the stainblocking agent is selected so that a 10-wt% solution of this agent in water has a pH of > 8 and < 11, preferably of > 8.5 and < 10.5. This has been found for many applications to be a good compromise between maintaining the advantageous properties of the stainblocking composition and potential damage to the fabric and/or carpet due to overly alkaline conditions. [0016] It should be noted that the pH of the stainblocking composition can of course be adjusted and stabilized by using for instance suitable buffer systems or alkaline solution such as sodium or potassium hydroxide, which is insofar a preferred embodiment of the present invention. However, for many applications it has been found that the use of a buffer system is not needed therefore according to an alternative embodiment of the present invention, the stainblocking composition is buffer-free.

[0017] According to a preferred embodiment of the present invention, at least one stainblocking agent of the stainblocking composition comprises an arylsulfonate moiety. It has been found for many applications within the present inventions that compounds comprising such moieties show excellent stainblocking properties.

[0018] The term“Arylsulfonate moiety” in the sense of the present invention means especially a moiety with the chemical structure Ar-SChH (or the deprotonated form) whereby the term Ar is an aryl group which can be further substituted.

[0019] In the present specification, "aryl group" refers to a hydrocarbyl group which can be created by formal abstraction of one hydrogen atom from an aromatic ring in the corresponding aromatic hydrocarbon. Aromatic hydrocarbon refers to a hydrocarbon which contains at least one aromatic ring or aromatic ring system. Aromatic ring or aromatic ring system refers to a planar ring or ring system of covalently bound carbon atoms, wherein the planar ring or ring system comprises a conjugated system of delocalized electrons fulfilling HiickeTs rule. Examples of aryl groups include monocyclic groups like phenyl or tolyl, polycyclic groups which comprise more aromatic rings linked by single bonds, like biphenylyl, and polycyclic groups comprising fused rings, like naphtyl or fluoren-2-yl.

[0020] According to a preferred embodiment of the present invention, the stainblocking agent of the stainblocking composition consists essentially out of compounds comprising arylsulfonate moieties. In the sense of the present invention, the term“consisting essentially” means >90 % (wt/wt), preferably >95% (wt/wt), more preferred >98% (wt/wt) and most preferred > 99% (wt/wt).

[0021] According to a preferred embodiment of the present invention, at least one stainblocking composition comprises an arylsulfonyl moiety. It has been found for many applications within the present inventions that compounds comprising such moieties show excellent stainblocking properties.

[0022] The term“Arylsulfonyl moiety” in the sense of the present invention means especially a moiety with the chemical structure Ar-SC -R whereby Ar is an aryl group which can be further substituted and whereby R is an alkyl or aryl group which can be further substituted.

[0023] In the present specification, when a definition is not otherwise provided, an "alkyl group" refers to a saturated aliphatic hydrocarbyl group. The alkyl group may be a Ci to C12 alkyl group. More specifically, the alkyl group may be a Ci to C10 alkyl group or a Ci to G, alkyl group. For example, a Ci to C4 alkyl group includes 1 to 4 carbons in alkyl chain, and may be selected from methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t- butyl. Specific examples of the alkyl group may be a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a pentyl group, a hexyl group.

[0024] According to a preferred embodiment of the present invention, the stainblocking composition consists essentially out of compounds comprising arylsulfonate moieties.

[0025] According to a preferred embodiment of the present invention, at least one of the stainblocking agents of the stainblocking composition comprises one or more of the following compounds:

- Arylsulfonates - Diarylsulfones

- Alkylalkylsulfones

- Alkylarylsulfonates

- Condensation products of Diarylsulfones and/or Alkylarylsulfones with carbonyl compounds, especially formaldehyde

- Condensation products of Diarylsulfones and/or Alkylarylsulfones with tanning agents

[0026] According to a preferred embodiment of the present invention, the stainblocking agents consists essentially of those compounds.

[0027] In the sense of the present invention, the term carbonyl compound especially means and/or includes the group -C(0)R ¹ R ² , wherein R ¹ and R ² are independently selected from: hydrogen; Ci-Ce-alkyl; phenyl; Ci-C ₆ -alkyl-C ₆ ¾

[0028] According to a preferred embodiment of the present invention, the stainblocking agents are selected from Rewin KF, Rewin KMB and Rewin KMR or mixtures thereof.

[0029] The present invention furthermore relates to a method comprising applying a stainblocking composition to a fabric and/or carpet, whereby the content of the applied stainblocking composition is > 1% to <10% (wt/wt) based on the weight of the fabric and/or carpet. Preferably the content of the stainblocking composition is > 2% to <8%

[0030] The present invention furthermore relates to a treatment system for fabrics and/or carpets comprising a stainblocking composition according to the present invention and a soil repellent composition.

[0031] According to a preferred embodiment of the present invention, the ration between stainblocking composition and soil repellent composition (in vol/vol) is > 1 : 1 and < 20: 1, preferably is > 1.5: 1 and < 10: 1 and most preferred > 2: 1 and < 4: 1 [0032] According to a preferred embodiment of the present invention, the treatment system comprises the stainblocking composition and the soil repellent composition as different entities, e.g. to be used in separate application units and/or systems or in different steps during the fabrication of the fabric and/or carpets.

[0033] However, according to an alternative preferred embodiment of the present invention, the treatment system comprises a mixture of a stainblocking composition according to the present invention and a soil repellent composition. This would allow for a simultaneous application of both the stainblocking composition and the soil repellent during fabrication of a carpet and/or fabric

[0034] According to a preferred embodiment of the present invention, the soil-repellent composition is fluorine free. Especially preferred are one or more of the following compositions XI to X4, which are described in the following.

[0035] The fluorine free composition XI comprises

A) A nanoparticulate silicate clay (also referred to as a clay nanoparticle);

B) An anionic acrylic-based copolymer binding agent;

C) water

[0036] whereby the mixing ratio is from 0.8 to 24 volume parts for A, from 1.3 to 23.8 volume parts for B, and the balance is C. Composition XI is useful for applications such as natural or synthetic fiber protection. Furthermore, following evaporation of water, the fibers treated with composition XI display improved water and soil repellency characteristics useful as substitutes for, and replacements of, the fluorinated fiber protectant compositions currently applied.

[0037] The fluorine free composition X2 comprises the components A, B, C and: D) A textile softening agent;

[0038] whereby the mixing ratio is from 0.9 to 22.5 volume parts for A, from 1.3 to 19 volume parts for B, from 0.7 to 11 volume parts D, and the balance is C. Composition X2 is also useful for applications such as natural or synthetic fiber protection.

[0039] The fluorine free composition X3 comprises the components B, C and D

[0040] The fluorine-free composition X4 comprises the components A and D.

[0041] Typical nanoparticulate silicate clays useful in the invention as component A include those described in U.S. Patent Application Publication No. 2011/0311757 to Iverson et al., which is incorporated herein by reference. These nanoparticulate silicate clays can be selected from the group consisting of smectites, kaolins, illites, chlorites, attapulgites, and combinations thereof. More specific examples include montmorillonite, bentonite, pyrophyllite, hectorite, saponite, sauconite, nontronite, talc, beidellite, volkonskoite, vermiculite, kaolinite, dickite, antigorite, anauxite, indellite, chrysotile, bravaisite, muscovite, paragonite, biotite, corrensite, penninite, donbassite, sudoite, pennine, sepiolite, palygorskyte, and combinations thereof.

[0042] The nanoparticulate silicate component, A, may be natural or synthetic. In one aspect the nanoparticulate silicate component includes synthetic hectorite. Regardless of whether the clay nanoparticle is natural or synthetic, the clay nanoparticle component may be present in an amount from about 0.9 to about 24 volume parts of the combined composition XL Typically, the clay nanoparticle is present in an amount of about 7 to about 14 parts by volume of the composition XL Examples of suitable nanoparticulate silicates are those commercially available from BYK Additives GmbH under the brand name Laponite®. These include Laponite® RD, Laponite® RDS, Laponite® JS, Laponite® SL25, and Laponite® S482. Laponite® SL-25 is a basic (pH 8-10), 21.5-25 wt% solids aqueous dispersion. The nanoparticulate silicate found in Laponite® SL25 has an average particle size of from about 20 nm to about 90 nm, and a surface area of from about 120 m2/g to about 500 m2/g;

Typical acrylic polymer components for use in the present disclosure as component B include those anionic or non-ionic, fluorine-free, water-dispersed acrylics that are known to act as binding agents, wherein the mixture including the acrylic copolymer binding agent (“binder”) forms a transparent or largely transparent coating. In some instances, the acrylic copolymer binder is self-crosslinking. When used according to the present disclosure, the water-based non-fluorinated acrylic copolymer provides a certain degree of durable water repellency to the treated carpets and fibers.

[0043] Binding agents useful according to this disclosure include any non-fluorinated emulsifiable acrylic polymer or copolymer suitable for use as a coating ingredient for soft surfaces, such as textiles, yarn, fabric, carpets, rugs, mats, or hard surfaces, such as vinyl tile, stone masonry, ceramic tile, and hardwood flooring. Many examples of such acrylic co polymers can be utilized as component B in the compositions described by this disclosure. Acrylic-based copolymers having at least one of acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethacrylate, methyl ethacrylate, ethyl ethacrylate, propyl ethacrylate, butyl ethacrylate, acrylic acid, and ethylene monomers, and combinations and blends thereof, are suitable candidates for use according to this disclosure. The acrylic-based copolymers can be non-ionic, or anionic, but the preferred acrylic-based copolymers in this disclosure have a net anionic charge association. Further, preferred components are those anionic acrylic-based copolymers that are self-crosslinking, and can thus crosslink by application of thermal and/or photoinitiated stimuli. Numerous non-fluorinated, emulsified acrylic copolymers suitable as component B are commercially available, such as the self- crosslinking families of RHOPLEX™ and PRIMAL™ emulsions, manufactured by Rohm and Haas Company. One preferred binding agent is PRIMAL™ ECO-36 (Rohm and Haas), which is an anionic, self- crosslinking acrylic based copolymer that can be applied on a substrate as a 46.5-47.5 wt% solids aqueous emulsion. Depending on process requirements, PRIMAL™ ECO- 16 (self-crosslinking, non-ionic, methyl methacrylate - ethyl acrylate copolymer) and PRIMAL™ ECO-8 (sel- crosslinking, nonionic) may also be used. As MMA/EA copolymers, corresponding polymer products from other manufacturers may also be used.

[0044] Another possible water-based acrylic copolymer may be ethylene acrylic acid copolymer (EAA). These dispersion polymers are also known under various tradenames. For example TECSEAL E-799/45 (Trub Emulsions Chemie), an ethylene-acrylic acid dispersion (solids content 45%, Tg 4°C), may be used. Still another possible water-based acrylic copolymer class may be styrene-acrylic copolymers.

[0045] It must be understood that the invention is not limited to the use of substances identified by certain tradenames, but other substance with similar properties for the purpose and effects of the invention may be used.

[0046] Acrylic copolymers of different types with differing mechanical properties may be blended with each other to achieve the desired final properties of the treated fiber. The advantages of the acrylic copolymers can be summarized as

- transparency,

- heat-curability,

- adhesivity or durability, and

- water repellency on fiber or carpet.

[0047] Typical textile softening agents for use in the present disclosure as component D, include those that are known to act as textile softening agents, wherein the mixture including the textile softening agent provides a smoother handle to the textile. Textile softening agents can act to improve the sewability of threads, or the softness or more pleasing tactile sensation of carpets and knitted fabrics. Textile softening agents can act to enhance lubricity when used to treat yarns, fabrics, textiles, carpets, and the like. Suitable examples of such agents are described by Rudat in U.S. Patent Appl. No. 2008 0287020 as being aminosilicones or aminosiloxanes, oils of various types, polyalkylene glycols, polyalkylene waxes, partially- oxidized polyalkylene waxes, lanolin and lanolin derivatives, fatty acids, fatty acid esters, oxidized or functionalized polyolefins, and stearates. Rudat describes the use of

aminosiloxanes as efficacious when combined with fluorochemicals and silsesquioxane- containing sols. U.S. Patent Appl. No. 2008 0287020 is incorporated herein by reference. Polysiloxane compounds, such as amino functional poly dime thylsiloxane; fatty acid condensation products, such as condensation products of hydrated tallow with 2- [2- aminoethyl) -amino] ethanol; and acetate salt (CAS No. 68425-52-5) or acryl compounds such as bis [acryl oxyethyl] -hydroxymethyl ammonium methyl sulfate (CAS No. 93334-15-7) are suitable in principle as softeners. A softener from the above mentioned compounds or a mixture of them can be included in the composition according to the invention. Suitable softeners have been described previously by Baumann in EP 1,746, 199 Bl. Such textile and carpeting softeners are commercially available, and examples of suitable products are Finistrol® AFN (fatty acid condensation product) of Thor, Speyer, Germany, and Megasoft® JET-LF of Huntsman Textile Effects, Langweid am Lech, Germany; Perrustol® CCA 500 (fatty acid condensation product) of Rudolf GmbH & Co. KG, Geretsried, Germany;

Raniesoft® TS 20 (fatty acid condensation product) of Ranie Chemie, Wiehl, Germany; Softycon N (fatty acid condensation product) Textilcolor AG, Sevelen, Switzerland;

Tubingal® OHS of CHT R. Beitlich GmbH, Tubingen, Germany; and Cefasoft NI (fatty acid condensation product) of Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Mohsdorf, Germany. EP 1,746, 199 is incorporated herein by reference.

[0048] The present invention furthermore relates to a method comprising applying a treatment system as described a fabric and/or carpet, whereby the content of applied the stainblocking composition is > 1% to <10% (wt/wt) based on the weight of the fabric and/or carpet.

Preferably the content of the stainblocking composition is > 2% to <8% [0049] The aforementioned components, as well as the claimed components and the components to be used in accordance with the invention in the described embodiments, are not subject to any special exceptions with respect to their size, shape, material selection and technical concept such that the selection criteria known in the pertinent field can be applied without limitations.

[0050] Additional details, characteristics and advantages of the object of the invention are disclosed in the subclaims and the following description of the examples which are illustrative only and not limiting. These examples do not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the present invention as claimed.

EXAMPLES

[0051] In the following, five 10 x 10 cm carpet test samples were prepared and investigated for stain resistance:

[0052] The term“owf’ means“on weight of fiber” and relates to the amount of solids of protective chemidal protectant applied after evaporation of solvent. The value of solids applied owf is typically expressed as a percentage of the mass of fiber present in the article.

[0053] I-Pro R01 #410.1 is a fluorine-free soil-repellent agent sold by Invista.

Rewin KF is a polymer of 4’4-sulfonylbisphenol sulfomethylated sodium salt with formaldehyd, Rewin KMB a polymeric aromatic sulfonate, Rewin KNR a condensation product of aromatic sulfonic acids; all three sold by CHT, Germany as fastness improving agent. Rewin ACP is a polyammonium compound sold by CHT, Germany as cationic after- treatment agent.

[0054] Using the Kool-Aid Test, the stain-resistance of the specimen was investigated. Whereas specimen 1 failed, specimen 2 gave a result of 1 and specimen 3 to 6 a result of 10.

[0055] The particular combinations of elements and features in the above detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the patents/applications incorporated by reference are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed.

[0056] Accordingly, the foregoing description is by way of example only and is not intended as limiting. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. The invention's scope is defined in the following claims and the equivalents thereto. Furthermore, reference signs used in the description and claims do not limit the scope of the invention as claimed.

TEST METHODS

[0057] 24 hour Kool Aid Test (standard test)

[0058] Equipment and Reagents:

[0059] Staining agent.

• Use cherry -flavoured, sugar-sweetened Kool-Aid.

• Prepare a 90 g Kool-Aid / 1000 cc water solution.

• Leave the solution to reach room temperature (22 ± 2 °C) before using.

[0060] Equipment:

• Use the specially designed impact tester to apply the staining agent to the carpet specimen.

[0061] Sampling:

To quality for certification, the test should be carried out on backed samples. Unbacked samples can be used, but for comparative tests only. (If an unbacked sample is to be tested it should be heated to 120 °C for 5 minutes prior to testing).

[0062] Procedure:

• Cut samples, measuring 10 cm x 10 cm, from the test carpet and clean the pile surface.

• Centre the impact tester on the 10 cm x 10 cm carpet sample, lift the plastic piston and fix it in the slot by turning sideways.

• Fill the attached syringe with the Kool-Aid solution (120 cc) and inject it evenly, through the 7 mm hole, over the surface of the test area on the carpet sample. • Release the plastic piston and let it drop freely onto the carpet sample. The impact corresponds to the impact of a cup of liquid falling from the table height (90 cm).

• Remove the impact tester and leave the carpet sample, undisturbed, in a horizontal position for 24 ± 4 hours.

• Without damaging the pile, rinse the sample thoroughly with tap water at ca. 20 °C, centrifuge them to remove any excess water and dry them in a forced air oven at maximum of 75 °C.

• Evaluate each sample for staining, using the AATCC Red 40 Stain Rating Scale (1 - 10, 10 = best)

• Ratings = 8 and better are acceptable.