MXPA00003121A - Liquid urethane compositions for textile coatings - Google Patents

Abstract

Disclosed is a polyurethane based composition for treating textiles to provide such treated textile with oil, water or oil and water repellency. The composition comprises a polyfunctional liquid polyurethane-containing adduct wherein the adduct contains as a first functional group at least one structo-terminal blocked isocyanate moiety per molecule, and at least one second structo-terminal functional group per molecule which is a perfluoro or siloxane moiety.

Description

COMPOSITIONS OF LIQUID URETHANE FOR TEXTILE COATINGS Field of the Invention The present invention relates to textile treatment compositions for imparting oil and water repellency in textiles, to methods for the treatment of textiles and to the resulting treated textiles.

BACKGROUND OF THE INVENTION There are several processes for the treatment of textiles in order to impart some water and / or oil repellency. For example, the use of various fluorochemical compositions for such purposes on fibers and fibrous substrates is known. See, for example, Banks, De., Organofluorine Chemicals and Their Industrial Applications, Ellis Horwood Ltd., Chichester, England, 1979, pp. 226-234. Since fluorochemicals are generally expensive, extenders are usually added to reduce the cost. Considerable effort has been made to find suitable extenders for use with fluorochemicals in order to impart water and oil repellency in fibers. U.S. Patent 5,466,770 discloses an oil and water repellent fluorochemical agent together with a polymer extender and a polymer extender having a saturated carbon-carbon backbone chain and at least one per cent. weight percent, based on the weight of the extender, of interpolymerized units derived from an ethylenically unsaturated monomer containing at least one blocked or masked isocyanate group. The U.S. Patent No. 3,849,521 (Kirimoto et al.) Discloses water and oil repellent compositions containing a water and oil repellent polymer containing fluoroaikyl and an additive copolymer containing monomer units having the formula wherein R-i, R2 and R3 represent hydrogen atoms or methyl groups and R4 represents a C-iß alkyl group; and monomer units having the formula CH2 = CR5CONHCH2? H, wherein R5 represents a hydrogen atom or a methyl group. The U.S. Patent No. 4,834,764 (Denier et al.) Discloses the use of certain blocked isocyanate compounds in combination with reactive perfluoroalkyl containing (co) polymers. It is said that such compounds improve oil and water repellency and also make possible a reduction in the amount of compounds containing fluoroaikyl. World patent publication WO92 / 17636 (Dams et al.) Discloses certain compositions comprising a fluorochemical agent, a copolymer extender and a blocked isocyanate extender.

SUMMARY OF THE INVENTION The present invention provides a reactive adjusted molecule, suitable for a thin, chemically bonded textile coating, which provides water and oil repellency without significantly impacting the feel of the fabric. In a first aspect, this invention relates to a composition based on liquid polyurethane comprising an addition product containing polyfunctional liquid polyurethane, wherein the addition product contains as a first functional group at least one blocked isocyanate unit terminal structural per molecule and at least a second structural terminal functional group per molecule, which is a repellent unit, preferably a perfluoro or siloxane unit or a combination thereof. In a second aspect, this invention relates to a process for preparing a polyfunctional liquid polyurethane-containing composition as mentioned above, by means of a solvent-free multi-step process, which comprises the reaction, in a first step, of a polyisocyanate with a polyol in order to provide an isocyanate-terminated intermediate, in a second step, the reaction of the isocyanate-terminated intermediate with a blocking agent in order to block at least one isocyanate unit and, in a subsequent step, the reaction of at least one isocyanate unit with a repellent compound. In a preferred method for the preparation of polyfunctional polyurethane: a) the polyisocyanate comprises at least two isocyanate units per molecule with mutually different reactivities towards the polyol; b) the polyol is an organic substance having a molecular weight of from 60 to 20,000 and containing per molecule from two or more isocyanate-reactive functional groups selected from the group consisting of -OH, -SH, -COOH, -NHR, wherein R is hydrogen or alkyl or epoxy; and c) the repellent compound is a molecule containing an isocyanate-reactive functional group selected from the group consisting of -OH, -SH, -COOH, -NHR, wherein R is hydrogen or alkyl or epoxy and further contains a second group functional which is not an isocyanate or an isocyanate-reactive unit, characterized in that: i) the first stage is conducted under essentially anhydrous conditions and in the absence of a urethane-promoting catalyst, the polyol is added at a controlled rate to the polyisocyanate of such so that the reaction temperature does not exceed 100 ° C and the total amount of polyol added is less than a stoichiometric equivalence with respect to the polyisocyanate; ii) for the second step, the blocking agent is added in a total amount less than a stoichiometric equivalence with respect to the isocyanate content of the intermediate; iii) and in one or more subsequent steps, a repellent compound is added such that the final polymer is substantially free of any isocyanate functionality or any functionality reactive to the isocyanate. In another aspect, the invention relates to a process for the preparation of a polyfunctional polyurethane according to the above, wherein stages (ii) and (iii) are inverted. In this way, in the stage (ii), a repellent compound is added in an amount less than the stoichiometric equivalence with respect to the isocyanate content of the intermediate compound and in step (iii), the blocking agent is added. In yet another aspect, this invention relates to, a process for imparting water and oil repellent properties in a textile comprising the application, on a surface of a textile, of a quantity of the composition set forth above sufficient to impart repellent properties. to water and / or oil to it. Such treated fibers are preferably heated in a second stage at a temperature and for a time sufficient to harden the treated substrate. This invention also relates to a repellent textile, resulting from the treatment of such a textile by the method described above. The treatment of fibers by the composition and method of the present invention is advantageous because the fiber retains the feel, feel, hue and softness originally possessed by the fibers even after the treatment and imparts a water and / or oil repellency. in such fibers. An additional advantage of the compositions of the present invention for the treatment of textiles is that the urethane compositions have a self-emulsifiable behavior and due to the nature of the compounds, their architecture can be adjusted to result in smaller emulsion particles. This imparts the advantage of applying a thinner coating of the above composition against conventional water repellent compounds. A further advantage of the present invention is that when the repellent unit is a perfluoropolyether, such compounds allow self-organization to take place at room temperature so that the textile does not need to undergo a heat treatment after rinsing. The polyfunctional polyurethanes of the present invention provide a further advantage since when applied to a textile, they are chemically bonded to the textile so that the water and / or oil repellency of such treated textiles is maintained by the textile after repeated rinsings. or of a prolonged use.

When used herein, the term "textile" refers to both textiles that are composed of natural fibers and / or synthetic fibers, for example wool, cotton, silk, nylon, cellulose and also mixtures of natural fibers and synthetic fibers, including synthetic fibers modified to react with an isocyanate functionality. The treated textile can be in the form of a fiber, a yarn, a woven fabric, a carpet, a knitted fabric, a nonwoven fabric that is formed from the fibers. The term "repellent unit" or "repellent compound", or variations thereof, means a unit or compound which, when added to a textile, will give the textile characteristics of water, oil or oil and water repellency. Preferred repellent units are perfluorocarbons and siloxanes. Perfluorocarbons are generally characterized by imparting to a textile the ability to repel water and oil and siloxanes are characterized by imparting to a textile the ability to repel water. The ability to repel oils is also associated with dye resistance.

DETAILED DESCRIPTION OF THE INVENTION The composition of this invention is characterized in that it comprises a polyfunctional liquid polyurethane addition product containing a blocked isocyanate functional group and a different second functional group which is a repellent unit. By the term "liquid" is meant that the addition product is a liquid at a temperature of 50 ° C or less and is preferably a liquid at a temperature of from 0 ° C to 50 ° C. The composition advantageously comprises the addition product in an amount of from 1 to 99, preferably from 5 to 95, more preferably from 10 to 90 and even more preferably from 50 to 90 weight percent, based on the total parts by weight of the composition. The addition product containing polyfunctional liquid polyurethane has a polyol core extending by chain with an isocyanate unit and ending with at least two functional groups. These functional groups are structural terminals, that is, they are not dependent. At least one chain end contains a blocked isocyanate functional group and at least one chain end contains a repellent functional group. In a preferred embodiment of this invention, the addition product has an average of from 2 to 8, more preferably from 3 to 8, and even more preferably from more than 3 to 6 chain ends per molecule, wherein each chain contains one or more urethane bonds. When the addition product contains from 2 to 8 chain ends per molecule; then there are from 1 to 7 blocked isocyanate units per molecule and from 7 to 1 functional perfluoro units. The optimum proportion of the masked isocyanate unit and the second functional unit will depend on the fabric proposed to be treated and can vary within the ranges of from 1: 7 to 7: 1, and preferably from 1: 2 to 2: 1.

The polyfunctional liquid polyurethanes of the present invention may contain additional functional units such as an aryl, alkyl, ester, nitrile, alkene, alkyne, halogen, silyl or combinations thereof. The equivalences of the repellent units, the blocking agent and optionally the additional functional groups are such that the polyfunctional polyurethane is substantially free of any isocyanate functionality or any isocyanate-reactive functionality. In general, the repellent compounds useful in this invention include any of the agents known as useful in the treatment of textiles for obtaining repellency to oil, water or oil and water. Preferred repellent compounds are the known siloxane-containing fluoro-containing and siloxane-containing compounds useful in the treatment of textiles for obtaining water and / or oil repellency. The fluoro compounds, called Rr X for brevity, are stable, inert, non-polar and both oleophobic and hydrophobic. X refers to an isocyanate-reactive functional group where such functional groups include -OH, -SH, -COOH, -NHR, where R is hydrogen or an alkyl, or epoxy unit. The Rf group preferably contains at least 3 carbon atoms, more preferably from 3 to 20 carbon atoms and more preferably from 6 to 14 carbon atoms. Rf may contain straight chains, branched chains or fluorinated, aliphatic, cyclic, fluorinated, aromatic groups or combinations thereof. R can optionally contain heteroatoms such as oxygen, divalent or hexavalent sulfur, or nitrogen. It is preferred that Rf contains oxygen. It is preferred that Rf contains from 40 percent to 80 percent by weight of fluorine, more preferably from 50 percent to 78 percent by weight of fluorine. The terminal portion of the Rf group is preferably completely fluorinated, containing at least 7 fluorine atoms, for example, CF3CF2CF2-, (CF3) 2CF-, -CF2SF5, F (CF (CF3) CF2-O) 4CF (CF3) CH2 -. Perfluorinated aliphatic groups and perfluorinated ethers are the most preferred embodiments of R X. Examples of useful fluorochemical agents include, for example, Rf containing urethanes, ureas, esters, amines (and salts thereof), amides, acids ( and salts thereof), carbodiimides, guanidines, allophanates, biurets, oxazolidinones and other substances containing one or more Rf groups, as well as mixtures and mixtures thereof. Such agents are well known to those skilled in the art, see, for example, Kirk-Othrner, Encyclopedia of Chemical Technology, 3rd. De., Vol. 24, pp. 448-451 and many are commercially available as ready-made formulations. Useful fluorochemical agents can be polymers containing multiple Rf groups, such as copolymers of fluorochemical acrylate and / or methacrylate. Preferred siloxane compounds, useful in the present invention, may be represented by the general formula X- (CH2) n-O - [(SiO) (CH3) 2] m -CH3 where X is as previously defined; n is an integer from 1 to 20; and m is an integer from 1 to 12. Preferably, m is an integer from 2 to 15 and more preferably from 3-12. Preferably, n is an integer from 1 to 10 and more preferably from 2 to 8. M and n are generally selected such that the molecular weight of the siloxane compound is from 120 to 423,000. The siloxane compound is commercially available from ABCR GmbH & Co., Karlsruhe, Germany. The polyisocyanate used in the process for preparing the addition product has at least two isocyanate units per molecule and which, with respect to the isocyanate reactive group of the polyol, are distinguished by a difference in reactivity. The difference in reactivity optimizes the processing of a product that has a narrow molecular weight distribution and reduces the potential for the formation of larger oligomers, leading to non-liquid or gel-like products. When the polyisocyanate contains three or more isocyanate groups per molecule, then the relative reactivity of the individual isocyanate units is such as to minimize the formation of larger oligomers. Suitable polyisocyanates can be aliphatic or preferably aromatic polyisocyanates and especially aromatic or aliphatic diisocyanates. An advantage of using diisocyanates, when the relative reactivity of the individual isocyanate groups is different, is that it allows the amount of free polyisocyanate, without reacting, which may occur in the isocyanate-terminated intermediate, is limited to the subsequent advantage of the material requirements for the second stage of the process, and beyond the value of the addition product in terminal applications. Examples of suitable aromatic polyisocyanates include toluene diisocyanate, methylene diphenylisocyanate and polymethylene polyphenylisocyanates. Examples of suitable aliphatic polyisocyanates include isophorone diisocyanate, isopropylcyclohexyl diisocyanate and methylene dicyclohexyl isocyanate. Preferred are polyisocyanates comprising isomers of toluene diisocyanate, methylene diphenylisocyanate or mixtures thereof. 2,4'-methylene diphenylisocyanate and notably 2,4-toluene diisocyanate, or mixtures comprising such diisocyanates, are particularly preferred. As used in this, the term "polyol" refers to a compound having two or more isocyanate-reactive functional groups per molecule, wherein such functional groups include -OH, -SH, -COOH, -NHR, where R is hydrogen or an alkyl, or epoxy unit. A polyol containing -OH functionality is preferred. The polyol may contain up to 8 such functional groups per molecule, preferably from 2 to 8, more preferably from 3 to 8 and more preferably from more than 3 to 6 functional groups per molecule. The polyol used in the process of this invention has a molecular weight of from 60 to 20,000; preferably from 200, more preferably from 1000 and even more preferably from 2000; and preferably up to 15,000 and more preferably up to 10,000. In a preferred embodiment, the polyol is a polyester or particularly a polyoxyalkylene polyol wherein the oxyalkylene entity comprises oxyethylene, oxypropylene, oxybutylene or mixtures of two or more thereof, especially including oxypropylene-oxyethylene mixtures. Alternative polyols that can be used in the invention include polyols based on polyalkylene carbonate and polyols based on polyphosphate. The nature of the selected polyol depends on whether or not it imparts certain solubility to the addition product, which may be advantageous for certain applications and not suitable for other applications. The solubility in water can be improved by the selection of polyols having a lower molecular weight or a high oxyethylene content. Suitable polyoxyalkylene polyoids are exemplified by various commercially available polyols, as used in polyurethane, lubricant or surfactant applications and include polyoxypropylene glycols designated as VORANOL ™ P-2000 and P-4000 with molecular weights of 2000 and 4000, respectively; polyoxypropylene-oxyethylene glycols such as DOWFAX ™ DM-30 which is understood to have a molecular weight of 600 and an oxyethylene content of 65 weight percent, and SYNALOX ™ 25D-700 which is understood to have a molecular weight of 5500 and a oxyethylene content of 65 weight percent, all available from The Dow Chemical Company; polyoxyethylene triols available under the tradename TERRALOX ™ and designated as product WG-98 and WG-116 which are understood to have a molecular weight of 700 and 980, respectively, polyoxypropylene-oxyethylene triols designated as VORANOL ™ CP 1000 and CP 3055 which it is understood to have a molecular weight of 1000 and 3000, respectively, and VORANOL ™ CP 3001 which is understood to have a molecular weight of 3000 and an oxyethylene content of 10 weight percent and VORANOL ™ CP 6001 which is understood to have a molecular weight of 6000 and an oxyethylene content of 15 weight percent, all available from The Dow Chemical Company; polyoxypropylene hexols including VORANOL ™ RN-482 which is understood to have a molecular weight of 700, and polyoxyethylene hexols including TERRALOX ™ HP-400 which is understood to have a molecular weight of 975, both available from The Dow Chemical Company; polyether polyols of higher functionality including those based on carbohydrate initiators such as, for example, sucrose and exemplified by VORANOL ™ 370 available from The Dow Chemical Company. The blocking group is a conventional blocking agent that can be removed from the isocyanate under thermal conditions, such as those employed during the hardening of a fibrous substrate treated with a compound containing the blocked isocyanate group.

Conventional isocyanate blocking agents include alcohols such as 1,6-hexanediol, ethylene glycol, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, n-amyl alcohol, alcohol t-amyl, 2-ethylhexano I, glycidol; aryl alcohols (for example, phenols, cresols, nitrophenols, o- and p-chlorophenol, naphthols, 4-hydroxybiphenyl); C2 to Cs alkanone oximes (for example, acetone oxime, butanone oxime); benzophenone oxime; aryl thiols (e.g., thiophenol); organic carbanion active hydrogen compounds (e.g., diethyl malonate, acetylacetone, ethyl acetoacetate, ethyl cyanoacetate); epsilon-caprolactam; a primary or secondary amine (eg, butyl amine); hydroxylamine; and primary amino mercaptan and secondary amino mercaptans. Particularly preferred are blocked isocyanates which include those blocked with C2-alkanone oximes to Ce, for example, 2-butanone oxime, with a phenol, with a lactam, with 2-ethylhexanol or with glycidol. In a preferred embodiment of this invention, the polyisocyanate is toluene diisocyanate comprising, substantially, the 2,4-isomer; the polyol is a polyoxyalkylene polyol, especially a polyoxyethylene-oxypropylene polyol containing from 3 to 6 hydroxyl groups; the blocking agent is 2-butanone oxime and the preferred fluorocarbons are CF3CF2CF2-, (CF3) 2CF-, -CF2SF5, and F (CF (CF3) CF2-O) 4CF (CF3) CH2- The method for preparing the polyurethane compositions of the present invention comprises a multi-step process. The first step relates to the preparation of an isocyanate-terminated intermediate by reacting the polyisocyanate with the polyol at a reaction temperature not exceeding 100 ° C, under essentially anhydrous conditions. By "essentially anhydrous conditions" is meant that the water is present in an amount of less than 1500, preferably less than 750, more preferably less than 350 ppm of polyisocyanate and polyol reagents in total. The presence of water in an amount greater than this increases the risk of forming gel products or solids. The reaction temperature is advantageously from 20 ° C, more preferably from 35 ° C; and preferably up to 80 ° C, more preferably up to 70 ° C. At higher reaction temperatures, the beneficial effect of the relative isocyanate reactivity rates can be substantially decreased and, in addition, the isocyanate can be consumed by an undesirable reaction to the allophanate. The polyol is added at a controlled rate to the polyisocyanate, such that the reaction temperature does not exceed 100 ° C and the total amount of polyol added is a stoichiometric equivalent or less with respect to the polyisocyanate. The total amount of polyol advantageously does not exceed 0.99, preferably does not exceed 0.95 of an equivalent; and advantageously it is at least 0.1, preferably at least 0.25 and more preferably from 0.5 of one equivalent per equivalent of isocyanate. The first stage of the process is conducted in the absence of a processing aid. By the term "processing aid" in the context of this invention, we mean substances that promote the formation of a urethane bond by the reaction of the isocyanate with an active hydrogen atom. To minimize the potential formation of gel, solidification, it is advantageous to use polyols that do not contain any catalyst or catalyst finishing residues, for example, potassium acetate, which could promote the formation of urethane or the dimerization or trimerization of isocyanate. Additionally, to minimize the formation of gei when preparing the intermediate compound, it is advantageous to use polyols, especially polyols having an acid content. The intermediate compound can be characterized in that it has an isocyanate content of from about 0.5 to about 5, preferably from about 1 to about 4 percent by weight and is a composition comprising structures (I), (II) and (III) represented by the structural formulas: P (-A) b (I) A or A- (II) A- (PA) CPA (III) where: c > 1 A- is a residue of a polyisocyanate; A is a free polyisocyanate P is a residue of a polyol; and b is the number of groups reactive to the isocyanate, formally present in the polyol. The proportions and amounts of (I), (II) and (III) based on the total mole amount of said substances, in an amount of from: for (I), at least 65, preferably at least 75, more preferably at least 80 and up to 100 mole percent; for (II), less than 35, preferably less than 25, more preferably less than 15 and more preferably 0 mole percent; and for (III), less than 12, preferably less than about 10, more preferably less than about 7, even more preferably less than 5 and more preferably 0 mole percent. In a preferred embodiment, the composition of the addition product may comprise substances (I), (II) and (III) in the mole percent ranges from 65 to 90: from 30 to 5: from about 6 to 1, respectively, where the total is up to 100. With regard to purity, it is understood that the final product has a low content of free polyisocyanates and addition products represented by structures (II) and (III), respectively. The proportion and amounts of (I), (II) and (III) are carried out in the formation of addition products of the present invention. By way of example, when all the isocyanate units of the intermediate compound contain a blocking group or repellent group, the final addition product can be represented by the general structure (IV) (W-A). { b-d) -P- (A-M) d (IV) where P, A and b are as previously defined; M represents a blocking unit; W represents a repellent unit; and d is the number of blocked isocyanate groups. By the description herein, b is greater than d. The process minimizes the formation of structure-type substances (III), resulting in an addition product having a liquid characteristic at room temperature, especially when the polyol used in the preparation of the addition product formally contained three or more groups / molecules reactive to the isocyanate. The addition product III is illustrated with a linear structure although it may have a highly complex branched structure. When the resulting isocyanate-terminated intermediate has a high free, unreacted content of isocyanate and, before proceeding with the second stage of the process, it may be advantageous to reduce such content by, for example, distillation or extraction techniques, by use of suitable solvents including pentane or hexane. The unreacted, free isocyanate can participate in the second stage of the process by the proportion of capped products, the presence of which in the final product can be detrimental to performance in cen terminal applications. In the second step of the process, the isocyanate-terminated intermediate reacts with a less than stoichiometric amount of a blocking agent. The stoichiometry is such that it provides the desired content of capped isocyanate units. The process for blocking isocyanates can be carried out under conditions that are well known in the art. See, for example, Patents of U.S. 4,008,247; 4, 189.601; 4, 190.582; 4, 191, 843; and 4, 191, 833, the descriptions of which are incorporated herein by reference, and Z.W. Wicks, Progress in Organic Covers, volume 3, pages 73-99 (1975) and volume 9, pages 3-28 (1981). The temperature of the process is chosen at the convenience of the reaction time and may be greater than 80 ° C without significantly affecting the quality of the resulting product. Exposure to a temperature greater than 100 ° C should be minimized to avoid undesirable side reactions, such as the inverse of the blocking reaction. In a third or subsequent process step, the partially blocked isocyanate-terminated intermediate reacts with a repellent compound. When the repellent compound is the final functional unit by being added to an isocyanate-terminated intermediate compound, partially blocked, the repellent compound is added in an amount sufficient to "cap" the remaining reactive isocyanate groups in order to provide the final addition product. For the addition of a functional group to the blocked isocyanate-terminated intermediate, such as a repellent compound, the process temperature is chosen at the convenience of the reaction time and may be greater than 80 ° C. In general, exposure to a temperature greater than 100 ° C should be minimized in order to avoid undesirable side reactions. The reaction of the blocked isocyanate-terminated intermediate with a polyfunctional substance can, if desired, be accelerated by the use of a suitable urethane promoter catalyst. Representative of such catalysts include tertiary amine compounds and organotin compounds as used in the preparation, for example, polyurethane foam by the reaction of a polyisocyanate with a polyol. It should be noted that the use of a catalyst in this step can lead to final addition products having a higher viscosity than those prepared in the absence of catalyst. A third or subsequent step means at least one step in which a repellent compound reacts with an isocyanate-terminated, partially blocked intermediate. In this way, the third stage comprises a process where a repellent compound, such as a fluorocarbon, is added in an amount less than stoichiometric with respect to the reactive isocyanate groups and in a subsequent stage another unit is added functional. In this way, the process encompasses the addition of multiple repellent molecules or other functional units. The polyurethane compositions of the present invention can also be produced when the final step in the process is the addition of a blocking agent. In this manner, the isocyanate-terminated intermediate product produced in the first step reacts with one or more repellent compounds and, optionally, with other functional units, in an amount less than stoichiometric with respect to the reactive isocyanate groups. In the step, sufficient blocking agent is then added to provide a polyfunctional polymer containing isocyanate functionality, substantially not free. The polyfunctional polyurethanes of the present invention can be applied to the textile by common processes known to those skilled in the art. Polyfunctional polyurethane is generally applied through the use of a solvent. Preferred solvents are acetones, ethers and esters or mixtures thereof. Alternatively, a composition can be prepared in the form of an aqueous dispersion or emulsion and treat the textile therewith. The polyfunctional polyurethanes of the present invention are particularly advantageous when they contain a perfluorhether since they are capable of forming an emulsion in water. When water is used as a solvent, water is preferably present in an amount of 70 to 900 parts by weight based on 100 parts by weight of the composition of the invention.

A composition of the invention comprises the polyfunctional polyurethane, which contains the repellent functionality, in an amount sufficient to impart repellent properties to a fibrous substrate treated with the composition. The amount of the polyfunctional polyurethane constituting an effective amount can be readily determined by those skilled in the art and depends on the particular fluorocarbon agent used and the textile to be treated. When the composition of the invention is applied as a treatment to a fibrous substrate, such as a fabric proposed for use in a garment, it is preferred that the treated substrate comprises the polyfunctional polyurethane in an amount of 0.01 percent up to 5 weight percent based on the weight of the untreated fiber. An amount of 0.01 percent up to 3 percent by weight of the untreated fiber is more preferred. Once the polyfunctional polyurethane has been applied to a textile, the textile is cured at a temperature and for a time sufficient to provide a treated, hardened substrate. This curing process can be carried out at temperatures between 110 ° C and 190 ° C depending on the composition used in particular. In general, a temperature of 150 ° C is suitable for a period of 1 to 10 minutes, preferably 3 to 5 minutes. The curing process breaks the bond between an isocyanate functional group and the blocking agent and allows the isocyanate to react and form a chemical bond with the treated textile. He treated, hardened substrate can be cooled to room temperature and used as desired, for example, incorporated or transformed into a garment such as a raincoat. The need for a blocking agent in an isocyanate unit is to prevent the unit from reacting with water if the composition is to be applied to a fiber in a solvent containing water. In another aspect of the invention, if it is desired to apply a polyurethane composition containing a repellent unit without the use of a water solvent, the step of adding a blocking agent to an isocyanate unit can be omitted. This will result in an addition product containing polyfunctional liquid polyurethane, wherein the addition product contains as a first functional group at least one isocyanate unit per molecule. Such compositions can then be applied directly to the fibers without the need for an aqueous solvent. The invention is illustrated by the following examples, in which all parts and percentages are by weight, unless otherwise stated. EXAMPLE 1 To a flask adapted to a mechanical agitator were added 348.32 g of toluene diisocyanate (TDI) (2.0 mol) and the TDI was heated to 50 ° C under a nitrogen atmosphere. To this was added slowly, under heavy stirring, 500 g of a hexol (0.0833 mol). The final proportion of TDI / OH was 4/1. It was not used no catalyst during the formation of the prepolymer. The total addition time was 12 hours. After the addition, the reaction mixture was left stirring overnight at 50 degrees C. The reaction mixtures were then passed through a distillation unit to remove excess TDI. To the previous product obtained, 14.52 g (0.167 mol) of 2-butanone oxime were rapidly added under strong agitation. This was followed by the addition of 0.47 grams (0.05 weight percent based on the total weight of the reaction mixture) of dibutyltin dilaurate. Then 121.36 g (0.333 mol) of 1 H, 1 H, 2 H, 2 H-perfluorooctane-1-ol were added. The reaction mixture was allowed to stir for two hours at 50 ° C to complete the reaction. On average, through this process, four of the six terminal groups (isocyanate unit) are capped with a perfluoro group and the remaining two terminal groups are capped with 2-butanone oxime (blocked isocyanate groups). To verify the resistance to oil and water, contact angle experiments have been carried out on a sheet of regenerated cellulose (Rayophane 600p), covered by polyfunctional polyurethane. The Rayophane 600p (from UCB Films), which was chemically identical to the cotton fiber, was covered by spin casting (10 sec, 3000 rpm) of a 5 percent by weight tetrahydrofuran (THF) solution to obtain a thin and uniform layer of the previous product. Before contacting measuring angle, the cellulose sheet was tempered for 30 minutes at 150 ° C under vacuum. The contact angle was measured by the sessile fall method. This method is based on the direct measurement of the contact angle of a liquid drop settlement on a flat surface. Water and hexadecane were chosen to examine the contact angle. The water was chosen to measure the repellency to! water and hexadecane to measure oil repellency (since it has a surface tension similar to oil). With water, a contact angle of 1-1.6 degrees was measured and with the hexadecane a contact angle of 74.81 degrees was measured, equaling the fluorocarbon surfaces in general. Also, the Water Repellent Spray Test (AATCC test method 22-1989) and the Oil Repellency Test (AATCC test method 1 18-1992) showed water and oil repellent properties with values of 100 (repellency to water) and 5 (oil repellency). Other embodiments of the invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention described herein. It is intended that the specification and examples be considered only as exemplary, indicating the true spirit and scope of the invention by the following claims.

Claims (12)

1. CLAIMS 1. An addition product containing polyfunctional liquid polyurethane wherein the addition product contains as a first functional group at least one isocyanate unit blocked per structural terminal per molecule and at least one second structural terminal functional group per molecule, which is a water or oil repellent unit and the addition product is derived from an isocyanate-terminated intermediate, which is the reaction product of a polyisocyanate with a polyol.
2. 2. The polyurethane addition product according to claim 1, characterized in that the repellent unit is a perfluoro, a siloxane unit or a mixture thereof.
3. 3. The polyurethane addition product according to claim 2, characterized in that the addition product contains from 3 to 8 structural terminal ends per molecule.
4. 4. The polyurethane addition product according to claim 3, characterized in that the addition product contains from 2 to 7 terminal perfluoro units per molecule.
5. 5. The polyurethane addition product according to claim 3, characterized in that the addition product contains from 2 to 7 terminal siloxane units.
6. 6. The composition according to any of the preceding claims, characterized in that the addition product comprises from 60 to 100 mole percent of the composition.
7. 7. A method for imparting repellent properties to the water or oil in a fibrous substrate, characterized in that it comprises the application to the surface of the fibrous substrate of a composition according to any of claims 1 to 6.
8. 8. The method according to claim 7, characterized in that after application of the composition to the fibrous substrate, the fibrous substrate is heated at a temperature and for a sufficient time to harden the treated substrate.
9. The method according to claim 7 or 8, characterized in that the polyurethane addition product is present in the fiber substrate in an amount of 0.01 percent up to 5 weight percent based on the weight of the untreated substrate material. .
10. 10. A textile that is treated with the method according to any of claims 7, 8 or 9.
11. 1 1. An aqueous emulsion characterized in that it comprises an amount of the composition according to any of claims 1-6 sufficient to provide water or oil repellent properties in a substrate treated therewith.
12. 12. A process for preparing a polyfunctional liquid urethane-containing composition according to any of claims 1-6, by means of a multistage process, free of solvents, which comprises the reaction, in a first step, of a polyisocyanate with a polyol In order to provide an isocyanate-terminated intermediate, the reaction of the isocyanate-terminated intermediate with a blocking agent for blocking at least one isocyanate unit in a separate step, the reaction of an isocyanate unit with a water or oil repellent compound.