MXPA01004742A - Methods for reducing the flammability of cellulosic substrates - Google Patents

Abstract

Methods of rendering cellulosic materials fire retardant, and articles of manufacture including the materials, are disclosed. The methods involve applying a flame retardant composition to the material. In one embodiment, the composition includes a carboxylic acid-containing compound in the substantial absence of a phosphorous-based esterification catalyst or a basic, (i.e., metal alkoxide) catalyst. The material is heated to esterify at least a portion of the hydroxy groups. In another embodiment, the compositions include an amino acid, protein and/or peptide and optionally include one or more crosslinking and/or coupling agents. Enzymes are a preferred protein. The methods involve applying the composition to the material, and optionally involve covalently linking the amino acid, protein and/or peptide to the material, either directly or via a crosslinking agent. In a third embodiment, the compositions include one or more crosslinking agents, and, optionally, one or more phosphorus-based compounds. Dimethyloldihydroxyethylene urea, imidazole, imidazolidinones, dialdehydes, and dichlorotriazines are preferred crosslinking agents. The methods involve applying the composition to the material, and covalently linking the crosslinking agent to the material. An advantage of covalently linking the crosslinking agent to the cellulosic material is the lack of any potential toxicity associated with uncrosslinked fire retardants on the cellulosic material and the stability of the bonds between the material and the crosslinking agent to conventional steam cleaning and other carpet cleaning methods. In a preferred embodiment, the fire-retardant cotton-fiber composition is used to prepare cotton carpets or raised surface and lightweight apparel.

Description

METHODS TO REDUCE THE F AMILITY OF CELLULOSE SUBSTRATES FIELD OF THE INVENTION The present invention relates to methods for reducing the flammability of cellulosic substrates, including cotton fiber carpets and high-weight, lightweight garments.

BACKGROUND OF THE INVENTION Cotton, like most textile fibers, is combustible. As long as the cotton is in the presence of oxygen and the temperature is high enough to initiate combustion (360-420 ° C), untreated cotton will ignite (flame combustion) or scorch (flameless combustion). The degree of flammability depends on the construction of the fabric. Fabrics have different flammability requirements depending on the particular end use. Cotton fibers, without the use of special flame retardant finishes, meet virtually all of these requirements for most existing end uses. However, some developments of new cotton products REF: 129448 require special constructions or finishes to reduce its flammability. This is especially true in some countries, such as the United States, which have strict regulations that govern the flammability of these products. Ignition resistance is one of the most useful properties that can be imparted to cotton fibers and cotton textiles. Some of the end uses for cotton in textiles for garments, household furniture and industry, may depend on their ability to be treated with chemical agents (fire or flame retardants) that confer resistance against the flame (FR). End-uses that require flame retardant finishes include protective clothing (eg garments for foundry workers and uniforms for firefighters), children's sleepwear, furniture / upholstery, bedding, carpets, curtains and tents. Bell. Chemical agents to reduce the flammability of products containing cotton fiber and other cellulosic fibers are well known and generally grouped into two categories: durable and non-durable. The durable type does not tend to be removed in conventional washes and the non-durable type is removed in conventional washes.

The variable manufacturing cost of a flame retardant, durable, typical treatment is approximately 1 to 2 dollars per 91 centimeters (1 yard), depending on the weight of the fabric and other factors. This can be a major limitation. The flammability and flame resistance of cotton has been studied extensively and several extensive reviews of the material are available. Cotton is not currently the raw material of choice in the carpet industry. The carpet fiber business in the United States represents approximately 5,000,000 bales / year in the market, and cotton is less than one percent of this total market. A reason why cotton has been almost excluded from this large market for fibers is the difficulty it has in complying with the Flammable Fabrics Act. This regulation requires that all mats that are approximately 1.80 meters (six feet) by 1.20 meters (four feet) or larger and sold for residential use pass a flammability test. This test is commonly referred to as the "pill test". This requires the ignition of a methenamine pill, which is placed in the center of a carpet specimen of approximately 23 cm by 23 cm (nine inches by nine inches). The specimen fails if the flame is dispersed within approximately 2.5 cm (one inch) of a metal template containing a hole approximately 20 cm (8 inches) in diameter, which is placed on top of the carpet specimen before lighting the pill The specimen passes the test if the flame does not diffuse within approximately 2.5 cm (one inch) of the metal template. For a residential carpet to be salableAt least seven of eight specimens must pass the test. In addition, if the carpet has been treated with a flame retardant (with the exception of alumina trihydrate added to the reinforcement coating, then the carpet must be washed ten times as described in AATCC 124-1967 before the test. Numerous man-made fiber mats are currently available, many of which do not require any special treatment to pass the federal flammability requirements due to the nature of the test.Many synthetic carpet fibers will melt from the lit pill during the test of the pill, such that the pill eventually self-extinguishes.The fuel load provided by these carpets in a fire, which is already burning, is not considered by the test method.Other carpets of synthetic fibers, such as propylene, require a flame retardant such as alumina trihydrate. Alumina trihydrate is frequently added to a reinforcing (or backing) coating, as opposed to applying directly to the carpet fibers. Synthetic thermoplastic fibers such as polypropylene melt rapidly when exposed to a flame, for example during the pill test. The burning pill then falls quickly, due to gravity, on the reinforcement. The reinforcement typically includes three layers: a thermoplastic primary reinforcement layer (usually of polypropylene), a latex adhesive layer (which may contain the flame retardant) and a secondary thermoplastic reinforcement layer (usually polypropylene). Since the primary reinforcement is also a low melting point thermoplastic, it melts quickly and allows the burning pill to come into direct contact with the latex. Since latex often includes a retarder of the flame, it can then suppress the dispersion of the flames. Other fibers, such as wool and modacrylic, are inherently flame resistant. These can be elaborated in carpets which do not require special treatments to treat the pill test, required. Cotton rugs can also be made which do not require special treatments to pass the pill test. For example, a carpet of cut knots can be made from a 3/2 Ne yarn composed of 90 percent cotton and 10 percent low melting thermoplastic fiber. The low-melting fiber is allowed to melt, typically before tasseling the carpet. A carpet that includes 12 stitches per 2.54 cm (1 inch), a gauge of 0.9 mm (1/11 inch) and a hair height of 6.35 mm (1/4 inch) can be constructed from this thread. Such a carpet is generally dense enough, with a sufficiently low thread height, so that it will pass the pill test without any additional treatment. A disadvantage of relying on such low pile constructions when manufacturing cotton rugs is that this is very limiting from a design and marketing point of view. The consumer in the United States today has become accustomed to a wide variety of choices when selecting a carpet. Limiting substantially the choices of carpet construction is not a practical option for a successful marketing program. Another disadvantage of trying to reduce the flammability of a cotton (or cellulosic) carpet by the construction alone, is that achieving reduced flammability often means increasing the density of the area gr / m2 (11 / square yard) of the carpet. As the density of the carpet area increases, the cost also increases in general. This procedure is therefore very restrictive and could limit the market to a lower final price. Alumina trihydrate which is effective on certain thermoplastic fiber mats, is not typically effective on carpets containing cotton. On carpets containing cotton, the cotton thread that is low and in the vicinity of the burning pill will tend to singe but will maintain sufficient integrity to support, isolate and separate the burned pill from the carpet reinforcement. There is not sufficient heat flux to reach the alumina trihydrate contained in the latex reinforcement so that the alumina trihydrate is effective in suppressing the flame. The use of low-melting flame-retardant fibers instead of the low flame-retardant, non-flame-retardant fiber typical for the yarn has also been tried. Low-melting fiber, in general, offers the advantages of improved elasticity and tassel definition and minimizes loose fiber detachment from tassels. The test has shown that the low melting point fiber, retarder of the flame used in the thread is not effective. Although several explanations have been offered, the mechanism is not understood yet. Since the federal law of the United States requires that any carpet that has a flame retardant treatment (different from alumina trihydrate) be washed ten times before the flammability test, any flame retardant of this type, which is applied for that purpose, it must remain effective after ten domestic washings. Because household washes are rather effective at removing materials that are not chemically bonded to the fibers, durable flame retardants are generally the most effective. There have been many techniques for imparting properties of flame resistance, durable, to the cellulose substrates described in the literature. However, there are relatively few that are practiced today, due to the commercial availability of chemical products, safety problems, process control problems or other reasons. Durable flame retardants are typically more complex, more expensive and more difficult to apply than non-durable treatments. The main flame retardant finishes used on cotton are based on phosphorus. Two of the most common phosphorus based systems which are used to provide flame resistance, durable, to cotton substrates, are the "precondensate" / ammonia process and the reactive phosphorus process. In the "precondensate" / NH3 process, the flame retardant agent exists as a polymer in the fibrils of cotton fibers and is not chemically combined with OH groups in the cotton fiber. This process imparts flame resistance, durable, to 100% cotton fabrics when applied under proper application procedures. This produces fabrics with a good retention of resistance and feel to the touch. Proper application of precondensates to cotton fabrics requires proper preparation of the fabric, adequate padding / uniform application, adequate addition of phosphorus in relation to fabric properties, proper moisture control before ammonia treatment , the control of the passage of ammonia to ensure the adequate formation of the polymer, and the effective oxidation and washing of the treated fabric. This process is very useful for specialty applications that can command a very high price, such as protective garments for firefighters and other workers who may be exposed to fire or excessive heat. This is not generally practical for cotton rugs or lightweight raised surface garments that will be sold to the average consumer. The problems associated with this process include the high cost, the special equipment needed (ammonia chamber) that is not generally available, and the two drying steps that are required. Flame retardants based on reactive phosphorus are compounds (for example, N-methylol-dimethyl-phosphonopropionamide (MDPPA)) that react with cellulose, the main constituent of cotton fiber. These compounds can be used for cotton and for blends of cotton with low synthetic fiber content. The finish, usually applied to the fabric after the coloring step, promotes the formation of carbonization or scorching. The durability of the finish makes the resulting treated fabric suitable for curtains, upholstery, bedding and protective clothing.

Flame retardants based on reactive phosphorus are typically used by applying a pad / drying / curing method, in the presence of a phosphoric acid catalyst. The finish is sometimes applied with a methylated melamine resin to increase the binding / fixation of the agent to the cellulose, which increases the retardation of the fire. The backwash is generally required frequently with an alkali such as sodium carbonate, followed by the subsequent rinsing. The subsequent washing helps to reduce the loss of the resistance of the fabric. The process based on reactive phosphorus has the advantage of not requiring specialized equipment such as a curing unit with ammonia, and has less effect on the colorants than the precondensate process. However, this process can cause more loss of strength than the precondensate process. In addition, there may be a problem of durability associated with some washing treatments if the instructions of the chemical supplier are not followed. Flame retardants based on reactive phosphorus may be unsuitable for certain end uses, such as cotton carpet or cotton blend. This is especially true when the products contain formaldehyde, due to problems with respect to the human health effects of exposure to certain volatile organic compounds (VOCs) which may have been released from carpets or carpet reinforcements in past years. . Because of this, most carpet manufacturers generally consider very low levels of formaldehyde as unacceptable. Another problem is that these products are generally designed to be subsequently washed as part of the application process. While the toxicity of such materials is generally low, there are significant problems regarding the exposure of infants or young children to unfixed, residual chemicals left on the carpet. A non-phosphorous process to make cotton, fire retardant, has been to incorporate a mixture of water-insoluble solid particles of brominated organic compounds and metal oxides, optionally with a metal hydrate, into the fiber of the carpet (Patent of the States). United No. 4,600,606 to Mischutin). However, a limitation of the chemistry is that metal oxide compounds can be made soluble when they are washed if the pH of the solution is not on the acid side. Also, the particles of brominated organic compounds can be irritating to people who come in contact with them, and can be harmful if swallowed.

Another non-phosphorus process has been to prepare a solution of boric acid, ammonium sulfate, borax, hydrogen peroxide, and optionally a surfactant and / or an alkyl phthalate ester, and to apply this as a coating on cellulosic materials. A major limitation of this chemistry is the water solubility of the components, which results in the composition being substantially eliminated during conventional washing. The Patents of the United States Nos. 4,820,307, 4,936,865 and 4,975,209 to Welch et al. And U.S. Patent No. 5,221,285 to Andrews et al., The contents of which are incorporated by reference herein, in their entirety, describe the use of compositions containing carboxylic acid for crosslinking fibrous cellulosic fabrics, and providing textile materials with wrinkle resistance, smooth drying properties and durability to repeated laundry in alkaline detergents (see, for example, the Excerpts of each of the patents). The methods described in these patents require the use of phosphorus-based catalysts, and tend to provide a high degree of esterification over cellulosic textiles, which is advantageous for imparting wrinkle resistance but which can provide a very high degree of esterification for other uses. Because wrinkle resistance is not usually a property sought for carpets, the carpets have not been subjected to treatments with carboxylic acid described in the Welch and Andrews patents. In addition, with respect to garments based on high-surface cotton and lightweight, the relatively high concentration needed to impart wrinkle resistance could also be expected to adversely affect the "hand" of the resulting fabrics. When used in a concentration that could provide acceptable hand to the garment based on high surface and lightweight cotton, resistance against wrinkles may not be acceptable. There is a need for fire retardants for cotton fiber, especially when the fiber is used in a cotton rug or in a light weight raised surface garment, which survives a certain number of washes, including steam cleaning. The present invention provides such materials.

BRIEF DESCRIPTION OF THE INVENTION Methods for providing cellulosic fibers or products made from cellulosic fibers, with reduced flammability, are described. Cotton is a preferred cellulosic fiber. Other cellulosic fibers include flax, jute, hemp, ramia, Lyocell, Tencell® and unsubstituted, regenerated wool celluloses, such as rayon. In mode A, the methods involve application to a cellulosic fiber or products made from cellulosic fibers, of a composition that includes a carboxylic acid but which does not include a significant amount of an esterification catalyst based on phosphorus or a basic catalyst ( for example, a metal alkoxide) and the reaction of some or all of the carboxyl groups with some or all of the hydroxyl groups present on the cellulosic fiber. The carboxylic acid is one that is capable of reacting with a cellulosic substrate when heated to a temperature of between 100 ° and 200 ° C for between 15 and 30 minutes or less in the substantial absence of a phosphorus-based catalyst or a basic catalyst. Preferably, the carboxylic acid is maleic, malic, tartaric, succinic or citric acid, and may be in the form of polymers containing carboxylic acid such as the copolymers of meleic acid / acrylic acid. The carboxylic acids and hydroxyl groups are linked via ester linkages by heating the acid-treated cellulosic fibers, preferably at a temperature of between 100 and 200 ° C for between 15 minutes and 30 minutes or less. The esterification is carried out in the substantial absence of phosphorus-based or basic catalysts (for example, metal alkoxide). The absence of phosphorus-based catalysts avoids the presence of phosphorus-based materials in the final product, and also facilitates the imparting of a relatively low degree of esterification on the cellulosic material. The absence of basic catalysts increases the reaction rate, which may be preferred when prolonged reaction times may cause adverse reactions or are not practical. When the composition is applied to the cellulosic substrate, the percentage by weight of the fire retardant solution that is applied to the cellulosic substrate is typically between about 1.0 and 200 weight percent, preferably between about 5.0 and 100 weight percent, and more preferably, between about 15 and 80 weight percent of the fiber to be treated. These ranges vary depending on the mode of application and the cellulosic substrate being treated. For example, for the high-surface and lightweight garment, greater amounts of the fire retardant solution may be required to achieve adequate fire resistance. This same general principle of adjusting the concentration of the solution based on the addition of total moisture applies to other substrates as well, such as fiber fill or upholstery. The resulting cellulosic fiber is fire resistant and the ester bonds between the carboxyl groups and the hydroxyl groups on the cellulosic fiber are stable to most conventional washes, including the ten domestic washes specified in 16 C.F.R. 1630 and 1631 for carpets that have been treated with a flame retardant. In mode B, the methods involve application to a cellulosic fiber or to products that include a cellulosic fiber, of a composition that includes one or more amino acids, proteins and / or peptides, and optionally include one or more cross-linking agents and / or coupling. The methods involve the application to a cellulosic fiber, of a composition that includes an amino acid, a protein and / or peptide, and optionally involve the chemical combination of the amino acid, the protein and / or the peptide to the hydroxyl groups on the cellulosic fiber, using crosslinking and / or coupling agents. Suitable amino acids include synthetic and naturally occurring amino acids. The amino group may be in an alpha position to the carboxylic acid group, or it may be in different positions from or in addition to the alpha position. Many amino acids include reactive groups such as hydroxyl groups, thiols, amines and carboxylic acids. It is known that carboxylic acids react with hydroxyl groups under various coupling conditions using known coupling agents to form ester bonds. The thiols, amines and hydroxyl groups on the amino acids, proteins and / or peptides do not react directly with the hydroxyl groups on the cellulosic materials, but can be covalently linked via crosslinking agents. Preferred amino acids are those that are commercially available in large amounts, for example, lysine and arginine. The proteins and peptides are prepared by the formation of peptide bonds (amide) between various amino acids. Suitable proteins include soy proteins, milk proteins, such as casein, derivatives thereof and enzymes. In a preferred embodiment, the protein is an enzyme. Suitable enzymes include cellulases, lipases, catalases, amylases, proteases, pectinases, xylanases, isomerases and beta-glucanases. The crosslinking agents are reactive molecules that include two or more leaving groups, such as a thiol, amino and / or hydroxyl group on the amino acid, protein and / or peptide, can react with one of the groups and the other group can react with a hydroxyl group on a cellulosic material. Examples of suitable crosslinking agents include dichlorotriazines, ureas, imidazolidinones, imidazoles, dialdehydes, divinyl sulfones, urethanes, carbonates, orthocarbonates, chloroformate, dihalides such as 1,2-dichloroethane, diesters such as dimethylsuccinate, diacid halides such as succinyl chloride, and similar. The carboxylic acids on the amino acids, proteins and / or peptides and the hydroxyl groups on the cellulosic substrate can be linked via ester linkages with or without the use of coupling agents. In one embodiment, the esterification is performed using a catalyst and heat, using the esterification conditions described in U.S. Patent No. 4,820,307 to Welch et al., The contents of which are incorporated by reference herein. Conventional esterification conditions, for example, the formation of the acid halides and the reaction of the acid halides with the hydroxyl groups on the cellulosic material in the presence of a tertiary amine, can also be used. This modality may be less preferred due to the higher cost of raw materials. When the composition is applied to the cellulosic substrate by spraying or foaming, the percentage by weight of the fire retardant solution that is applied to the cellulosic substrate is typically between about 5 and 100 weight percent, preferably between about 10 and 50 percent by weight. weight, and more preferably, between about 15 and 30 weight percent of the fiber to be treated. These ranges vary depending on the mode of application and the cellulosic substrate to be treated. For example, for high-weight and light-weight garments, greater amounts of the fire retardant solution may be required to achieve adequate fire resistance. This same general principle of adjusting the concentration of the solution based on the addition of total moisture, applies to other substrates as well, such as fiber fill or upholstery. The amino acids, proteins and / or peptides can be applied by other application techniques including discharge. In a discharge application, the liquor ratio can vary over a wide range of about 2 to 1 to about 50 to 1. More preferably about 3 to 1 to about 20 to 1, which means that about 20 kg (or 20 pounds) ) of treatment solution per kilogram (or pound) of substrate containing cellulosic substrate. In a preferred embodiment, the liquor ratio is about 10 to 1 and the concentration of the amino acid, protein and / or peptide is adjusted accordingly to a concentration in the range of 0.001 percent to about 5.0 percent and preferably of about 0.01 to 1.0 percent by weight of the treatment liquor, which is equivalent to 0.1 percent to 10.0 percent of the weight of the cellulosic substrate. Wet coupling or crosslinking agents, which can also be applied by flushing techniques, from the same bath, can be applied with proteins, enzymes or amino acids to provide covalent bonds that result in treatments that are durable to various techniques. cleaning. A wet crosslinking agent of this type is known as T-DAS, a chlorotriazine. In mode C, the methods involve application to a cellulosic fiber or a substrate of a composition that includes one or more crosslinking agents and optionally includes one or more phosphorus-based compounds, such as phosphorus oligomers. The methods involve the application to a cellulosic substrate, of a composition that includes a crosslinking agent, optionally in the presence of a phosphorus-based compound, and covalently linking the hydroxyl groups on the cellulosic substrate to one or more of the groups on the agent of crosslinking. The crosslinking agents are reactive molecules that include two or more reactive groups, which are capable of reacting with the hydroxyl groups on the cotton, or with derivatives formed from the hydroxyl groups on the cotton, for example the mesylate, triflate leaving groups , and tosylate. Suitable groups on the crosslinking agent to react with the hydroxyl groups on a cellulosic substrate include the typical leaving groups in the chemistry of the nucleophilic displacement and the similar displacement chemistries. Suitable groups on the crosslinking agent to react with the hydroxyl group derivatives on a cellulosic substrate such as mesylates, and triflates, include typical nucleophiles in the nucleophilic displacement chemistry and similar displacement chemistries. Examples of suitable crosslinking agents include dichlorotriazines, ureas, imidazolidinones, imidazoles, dialdehydes, urethanes, carbonates, orthocarbonates, chloroformate, dihalides such as 1,2-dichloroethane, diesters such as dimethylsuccinate, diacid halides such as succinyl chloride, and the like. . The phosphoric acids and other functional groups containing reactive phosphorus on the phosphorus-based compounds and the hydroxyl groups on the cellulosic substrate can be linked by means of the crosslinking agents. In all the above embodiments, the treated fiber may be present alone or as mixtures of cotton and other commercially available fibers, including polyester (one example of which are polylactic acid polymers). The fibers can be used to prepare suitable articles of manufacture, including carpets, garments of elevated surface and of light weight, other articles of clothing, upholstery, and other articles that have acceptable resistance against the fire, based on the required tests for that particular use.

In a preferred embodiment, the fiber is cotton and the article of manufacture is a carpet based on cotton or a garment of high surface and light weight. The treated cotton mats may have a density between about 678 g / m2 (20 oz / yd2) and 4.068 g / m2 (120 oz / yd2), preferably between about 1.017 g / m2 (30 oz / yd2) and 2.712 g / m2 (80 oz / yd2). In all the above embodiments, the compositions may optionally include additional components, such as other fire retardants, colorants, wrinkle resistant agents, defoamers, buffers, pH stabilizers, fixative agents, stain repellents such as fluorocarbons, agents blocking of stains, dirt repellents, wetting agents, softeners, water repellents, dirt release agents, optical brighteners, emulsifiers, and surfactants.

DETAILED DESCRIPTION OF THE INVENTION Methods for providing cellulose fibers or cellulosic substrates, in particular cotton fibers, with reduced flammability, and the resulting articles of manufacture prepared from the flame resistant cellulosic fibers are described.

In mode A, the methods involve the application to a cellulosic fiber, of a composition including a carboxylic acid, preferably selected from the group consisting of maleic acid, malic acid, tartaric acid, succinic acid, citric acid, and acid copolymers maleic / acrylic acid, and a suitable solvent but that does not include a significant amount of an esterification catalyst based on phosphorus or a basic catalyst (eg, a metal alkoxide) and the reaction of some or all of the carboxyl groups with some or all the hydroxyl groups present on the cellulosic fiber. In mode B, methods that involve application to a cellulosic fiber, of a composition that includes one or more amino acids, proteins and / or peptides, and optionally include one or more crosslinking agents and / or couplings. The methods involve the application to a cellulosic fiber, of a composition that includes an amino acid, protein and / or peptide, and optionally involve the chemical combination of the amino acid, protein and / or peptide to the hydroxyl groups on the cellulosic fiber using crosslinking agents and / or coupling. In the C mode, the methods involve the application to a cellulosic fiber, of a composition that includes one or more crosslinking agents and optionally including one or more phosphorus-based compounds, such as phosphorus oligomers. The methods involve the application to a cellulosic substrate, of a composition that includes a crosslinking agent, optionally in the presence of a phosphorus-based compound, and covalently linking the hydroxyl groups on the cellulosic substrate, to one or more of the groups on the cellulosic substrate. crosslinking agent. Depending on the density of the cellulosic substrates, the substrate alone, such as the cotton carpet or the garment with the raised surface and light weight, may be almost fire resistant enough to meet the American requirements for flammability. A small increase in fire resistance may be enough to comply with the United States guidelines. Accordingly, the use of conventional fire retardants such as organophosphorous, halogenated aromatic compounds, and metal carbonates, which impart fire resistance, but which each have inherent problems associated with their use, can be avoided.

Definitions The following definitions are used herein: The term "pill test" as used herein is a test used to determine if a carpet is sufficiently fire resistant for home use. This requires the ignition of a methenamine pill, which is placed in the center of a carpet specimen of 23 cm x 23 cm (9 inches x 9 inches). If the flame diffuses within 2.5 cm (1 inch) of a metal template containing a hole approximately 20 cm (8 inches) in diameter, which is placed on top of the carpet specimen before turning on the pill, the specimen fails. If the flame does not disperse within 2.5 cm (one inch) of the metal template, then the specimen passes the test. For a residential carpet, as described above, for it to be sold, at least seven out of eight specimens must pass the test. In addition, if the carpet has been treated with a fire retardant (with the exception of alumina hydrate added to the reinforcement coating), then the carpet should be washed ten times as described in AATCC 124-1967 before the test.

The term "45 degree angle test" as used herein, refers to the flammability test for garments described in the Federal Code of Regulations Title 10, Part 1610. This test method determines the flammability of the fabrics with high surface fibers such as high or lightweight fabrics. This requires the placement of the specimen that is to be treated at a 45-degree angle and igniting it when exposing the surface to an open flame for a second. The flame should be approximately 2.5 cm (1 inch) from the tip of the flame to the gas nozzle. The speed and intensity of the flame dispersion allow the classification by category of the flammability of the fabric. The term "acceptable hand" as used herein refers to the sensation of the resulting substrate after it has been treated with the fire retardant composition. The term "cellulosic substrate" as used herein, refers to substrates including cellulosic fibers, such as cotton, jute, flax, hemp, ramia, Lyocell, Tencel®, wool celluloses unsubstituted, regenerated, such as rayon, mixtures thereof, and mixtures with other fibrous materials in which at least about 25 percent, preferably at least about 40 percent, of the fibers are cellulosic materials. The term "fibers" refers to fibers present in a substrate, such as a carpet, high-weight and light-weight garments, upholstery, knitted, knitted, and non-woven fabrics, and the like. The term "fire retardant" as used herein, refers to the chemical applied to the cellulosic substrate. The term "flame resistant" refers to the treated cellulosic substrate. The terms "flame resistant" and "reduced flammability" as applied to substrates are not intended to imply that the materials are fireproof, or that they will not burn.The term "fire retardant effective amount" refers to to an effective amount such that the treated substrate passes the required flammability test for that particular substrate.The term "degree of substitution" refers to the number of hydroxyl groups in the cellulosic substrate, which are esterified, on average, per glucose portion. For example, fire resistance can be obtained by esterification of a relatively low number of hydroxyl groups on average on the cellulosic substrate.

The term "light weight fabrics" refers to fabrics with an area density of less than 88.1 g / m2 (2.6 ounces / square yard) for clothing in general, as defined by the Code of Federal Regulations of the United States. United, 16 CFR section 1610.

I. Fire Retardant Composition Used in Mode A The fire retardant composition includes a carboxylic acid containing portion, a suitable solvent and, optionally, additional components that preferably do not infer to a significant degree with the chemistry of the esterification.

A. Portions Containing Carboxylic Acid Any aliphatic, alicyclic, or aromatic mono-, di-, tri- or polycarboxylic acid can be used, which can be covalently bound to a cellulosic substrate when an aqueous solution of the acid is applied to the cellulosic substrate and the substrate is heated. Preferably, in the aliphatic polycarboxylic acids, each carboxyl group is two or three carbon atoms away from the other carboxyl group. Preferably, in the aromatic polycarboxylic acids, each carboxylic group is ortho to the other carboxylic group. In one embodiment, the compounds are linear, branched or cyclic di-, tri- or polycarboxylic acids of 2 to 20 carbon atoms, wherein an oxygen or sulfur atom is optionally present at one or more sites on the molecule. Examples of such compounds include maleic acid, malic acid, fumaric acid, tartaric acid, citric acid, citraconic acid, itaconic acid, tricarbalilic acid, trans-aconitic acid, 1,2,3,4-butacarboxylic acid, all-cis-1, 2, 3, 4 acid - cyclopentanetracarboxylic acid, melitic acid, oxydisuccinic acid, thiodisuccinic acid, and the like, or anhydrides or acid halides of these acids. Preferred carboxylic acids are maleic acid, malic acid, succinic acid, tartaric acid, citric acid, and maleic acid and acrylic copolymers. In yet another embodiment, the compounds are polymers that include at least three carboxyl groups. Examples of such compounds include poly (meth?) Maleic acid, carboxymethyl cellulose, poly (meth) acrylic acid, polymaleic acid, polyacrylic acid, copolymers and mixtures thereof, and acid anhydrides or halides of these acids. Also suitable are carboxymethylcellulose fixed with an external crosslinker, and gluconic acid fixed by an external crosslinker. Preferably, the carboxylic acids include at least two carboxyl groups, to effectively link at least a portion of the hydroxyl groups on the cellulosic material. However, the mechanism of flame resistance, apparently, is through the decarboxylation of the carboxylic acid during combustion. Some of the dicarboxylic acids also contain hydroxyl groups that can be released as water vapor during combustion. The acids can also promote the formation of carbonization. Since ester bonds appear to work by releasing carbon dioxide when the material is ignited, it may be sufficient to use monocarboxylic acids to achieve adequate fire resistance, alone or in combination with di-, tri- and polycarboxylic acids . The carboxylic acids may optionally include other reactive functional groups, for example, carbon-carbon double bonds, halides, amines, phosphorus esters, monosaccharides, disaccharides, polysaccharides, amides and imides. The presence of olefins may allow additional crosslinking, and the presence of halides may provide additional resistance against fire. The perfluoroalkyl and perfluoroaryl groups can impart dirt resistance properties to the composition. The hydroxyl groups, which may be present, may not be preferred as these may interfere with the desired coupling chemistry and also cause some yellowing in the treated fiber compositions.

B. Suitable Solvents Preferably, the carboxylic acid is present in an aqueous solution, dispersion or suspension. However, other volatile solvents which are inert to coupling chemistry can be used, and in which the carboxylic acid is soluble or uniformly dispersible. The composition may be in the form of a solution or an emulsion.

C. Optional Components The additional components can optionally be added to the fire retardant composition. These include, but are not limited to, other fire retardants, pigments, wrinkle-resistant agents, defoaming agents, buffers, pH stabilizers, fixing agents, stain repellents such as fluorocarbons, blocking agents of the stains, repellents of dirt or grime, wetting agents, softeners, water repellents, stain release agents, optical brighteners, emulsifiers, and surfactants. Suitable additional fire retardants include, but are not limited to, metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus-based acids, alumina trihydrate, and nitrogen-containing compounds.

II. The Retarder Composition of Fire Used in Modality B The fire retardant composition includes an amino acid, a protein and / or peptide, and may also include a crosslinking agent and / or coupling agent, as well as various other optional components, together with a suitable solvent. In some embodiments, the amino acid, the protein and / or the peptide will be covalently bound to the cellulosic material. In other modalities, it will not be covalently bound to the cellulosic material. In those embodiments in which crosslinking is desirable, it may be necessary to use a crosslinking or coupling agent.

A. Amino Acids, Proteins and / or Peptides Amino acids are organic acids that contain a basic amino group and an acidic carboxylic acid group. These are amphoteric and exist in aqueous solution as dipolar ions. There are twenty-five amino acids of natural origin that are constituents of proteins and peptides of natural origin. These naturally occurring amino acids have an amino group in an alpha position to the carboxylic acid group. However, amino acids of non-natural origin can also be used in the compositions and methods described herein. Some amino acids that include various functional groups, such as the amine, thiol, hydroxyl and carboxylic acid groups, in addition to the amine and carboxylic acid groups, are present in all amino acids. The proteins and peptides are polymers formed by the sequential linkage of various amino acids. The amino group of an amino acid and the carboxylic acid of the next amino acid are linked via an amide bond, also known as a peptide bond. Proteins are produced naturally, and can also be produced in protein synthesizers and by fermentation techniques. A difference between proteins and peptides is the size of the molecules. Peptides typically include between 2 and 100 amino acids, and proteins typically include more than 100 amino acids. There are numerous proteins and peptides, both natural and synthetic, all of which can be used. In some embodiments, the proteins are modified with reactive groups that make it possible for them to be covalently bound to the cellulosic material, without the need for an additional crosslinking or coupling agent. Such proteins may be preferred because of their relative ease of application. Examples of proteins include vegetable proteins such as soy proteins, milk proteins, such as casein and enzymes. Enzymes are complex, very large protein molecules that consist of intertwined amino acid chains. These are formed within the cells of all living creatures, plants, fungi, bacteria, and simple unicellular organisms, microscopic. These are typically highly biodegradable and do not impose risk to the environment. Enzymes can be classified by categories according to the compounds on which they act. For example, lipases divide fats into glycerol and fatty acids, catalases break down hydrogen peroxide, amylases break starch into simple sugars, proteases break proteins, cellulases break cellulose, pectinases break pectin, xylanases break xylan, isomerases catalyze the conversion of glucose to fructose, beta-glucanases break beta-glucans, maltases convert maltose to glucose, trypsin breaks down proteins to amino acids, zymoses convert sugar to alcohol and dioxide. carbon. Suitable enzymes include cellulases, lipases, catalases, amylases, proteases, pectinases, xylanases, isomerases, maltases, zymeses, trypsin, endoglucanases, beta-glucanases, and others, which, when applied to a cellulosic material, provide the material with the desired level of fire resistance for the intended application. The enzymes described herein are either commercially available or can be prepared using known methodology. Enzymes are typically produced commercially by heating a fermentation broth under aseptic conditions to form a completely sterile nutrient medium. The nutrient is converted to a desired enzyme by the action of the carefully selected microorganism, in the presence of oxygen. The choice of the broth, the microorganism, and the operating conditions determine the type and yield of the enzyme. Once the fermentation is complete, various centrifugation, filtration, and precipitation processes separate the enzyme from the fermentation broth. It is believed that the mechanism of fire resistance involves, in part, the decarboxylation of carboxylic acid groups in amino acids, proteins and / or peptides during combustion. Some of the amino acids, in the amino acids, proteins and / or peptides also contain hydroxyl groups that can be released as water vapor during combustion. The carboxylic acids can also promote the formation of carbonization. The nitrogen contained in the amino acids, the proteins and / or the peptides can also serve to reduce the flammability of the substrate. Since the enzymes are separated from the amino acids, they include various reactive groups such as hydroxyl groups, thiols, amines, and carboxylic acids. It is known that carboxylic acids react with hydroxyl groups under various coupling conditions to form ester bonds. The thiol, amines and hydroxyl groups on the enzymes do not react directly with the hydroxyl groups on the cellulosic materials, but can be covalently linked via the crosslinking agents.

B. Crosslinking agents The reactive groups (hydroxyl, thiol, amine and carboxylic acid groups) on the amino acids, proteins and / or peptides can be covalently linked to the hydroxyl groups on the cellulosic substrate by means of the crosslinking agents. Reactive functional groups that participate in nucleophilic substitution reactions are typically nucleophilic, for example, amine, hydroxyl, and thiol groups, or leaving groups, for example, chlorides, tosylates, mesylates, and the like. Using the nucleophilic substitution chemistry, two nucleophiles or two leaving groups can be directly linked. However, it is possible to link the nucleophilic groups on two molecules by reacting them with a simple molecule which has two leaving groups, or a functional group capable of reacting with both nucleophiles. This type of molecule is known as a crosslinking agent. The crosslinking agents are well known to those skilled in the art.

The crosslinking agents can be used to covalently link the thiol, amine, carboxyl and / or hydroxyl group on the amino acids, proteins and / or peptides with the hydroxyl groups on the cellulosic material. Preferably, a sufficient amount of the crosslinking agent is present to covalently bind at least a sufficient amount of the amino acid, the protein and / or the peptide to the cellulosic material, to make it fire resistant sufficiently for the intended use. Some crosslinking agents include a functional group that is capable of reacting with two or more nucleophilic groups under appropriate conditions. Examples thereof include ureas, carbonates, orthocarbonates, chloroformates, urethanes, phosgene, diphosgene, triphosgene, thiophosgene, and the like. Of these, ureas and other water-soluble crosslinking agents are preferred because of their relative ease of use and the omission of the use of organic solvents. Other crosslinking agents include two or more functional groups which are capable of reacting with a nucleophilic group. Examples include alkyl halides, alpha-halocarbonyl compounds such as acid halides, sulfonyl halides, anhydrides, esters, epoxides, oxiranes, divinyl sulfones, thiol esters and the like. Examples of suitable dihalides include 1,2-dichloroethane, and 21,3-dichlorobutane. Examples of suitable diesters include dimethyl succinate and dimethyl oxalate. Examples of suitable diacid halides include succinyl chloride and oxaloyl chloride. Preferred crosslinking agents are water soluble, and react with the cellulosic substrate under relatively mild conditions (e.g., temperatures less than about 200 ° C, pH between about 2 and 12) and do not contain appreciable amounts of formaldehyde or other materials that known to be toxic to humans or animals after exposure. A preferred water-soluble crosslinking agent is a urea such as dimethyloldihydroxyethyleneurea, imidazole, imidazolidinone, dialdehyde and dichlorotriazine. Diclotriazinyl compounds are well known to those skilled in the art and have been used for years as crosslinking agents. Many of these compounds comprise carboxylic acid or sulfonic acid groups, so that the compound is relatively soluble in water at a certain pH range. An example of a suitable dichloritriazinyl compound is N, N'-bis (diclcro-s-triazinyl) -4,4'-diaminostilben-2, 2'-disodiosulfonate (T-DAS), which is well known to bind to cotton and also to the aminium, thiol and hydroxyl groups (see, for example, Lewis and Lao, "The use of a crosslinking agent to achieve the covalent attachment of hydroxyethyl sulfone pigments on cotton", AATCC 1998 International Conference and Exhibition, Philadelphia Marriott, Philadelphia, Pa, pages 375,383 (September 22-25, 1998), the contents of which are incorporated by reference herein.). Dialdehydes are also well known to those skilled in the art, and have been used for years to cross-link various compounds to proteins and peptides. Examples include dialdehydes of 2 to 6 carbon atoms, such as oxallaldehyde (Gloxal), succinidialdehyde and glutaraldehyde. These are typically sold as aqueous solutions, which are at least partially hydrated. Hydroxyl groups are known to react with these compounds to form acetals and hemiacetals. Amides, ureas and urethanes also react with dialdehydes to form various condensation products. The amines typically react with dialdehydes to form Schiff bases, which, if relatively unimpeded, react additionally to form more uncharacterized, more complicated products. The reaction with the amide groups described above tends to proceed faster in alkaline media than in acid media. Imidazolidinones are commonly used in the textile industry. An example is dimethyloldihydroxyethyleneurea (DMDHEU). DMDHEU is commercially prepared from glyoxal, urea and formaldehyde, and frequently contains residual formaldehyde. The presence of residual formaldehyde is not advantageous when contact of cellulose materials treated with animals or humans is anticipated. There are several commercially available imidazole derivatives, commonly used as crosslinking agents in the textile industry. These include the Fixapret ™ family of crosslinking agents, sold by BASF, including Fixapret NFMR, which is commonly used with a catalyst system that includes a proprietary blend of inorganic salts (Catalyst NB-202 from BASF). Examples of suitable water-soluble crosslinking agents include Fixapret® NF (BASF) and Freerez® NFR (BF Goodrich).

C. Coupling Catalysts A means for coupling amino acids, proteins and / or peptides to a cellulosic substrate without using crosslinking agents is to form the ester linkages with the carboxylic acid groups on the amino acids, proteins and / or peptides and the hydroxyl groups on the cellulosic substrate. Suitable coupling catalysts are well known to those skilled in the art. It may be necessary to protect the groups on amino acids, proteins and / or peptides that can interfere with the coupling chemistry, for example, the amine groups, if any, prior to the formation of the ester linkages. There are several types of catalysts that can be used to esterify the carboxyl groups on the amino acids, proteins and / or peptides with the hydroxyl groups on the cellulosic materials. Examples of suitable catalysts include alkali metal salts of the phosphorus-containing acids, including phosphorous acid, hypophosphorous acid, and polyphosphoric acid, and also include monoacid phosphates and alkali metal diacids and also hypophosphites thereof. The most active catalysts of this type appear to be alkali metal hypophosphites.

C. Suitable Solvents Preferably, the amino acids, proteins and / or peptides, together with any suitable combination of cross-linking agents and / or coupling, are present in an aqueous solution, suspension or dispersion. However, other volatile solvents that are inert to coupling chemistry and in which these materials are soluble, or uniformly die-dispersible, can also be used.

D. Optional Components Additional components can optionally be added to the fire retardant composition. These include, but are not limited to, other fire retardants, colorants, wrinkle resistant agents, defoamers, buffers, pH stabilizers, fixing agents, stain repellents such as fluorocarbons, stain blocking agents, repellents. to dirt, wetting agents, softeners, water repellents, stain release agents, optical brighteners, emulsifiers and surfactants. In one embodiment, the cellulosic substrate is a carpet. When other fire retardants are used in carpets, these may be present in or on the carpet fiber or reinforcement material.

Preferably, no formaldehyde or other volatile organic compounds are released from the reinforcing layer. In addition, fire retardants are preferably compatible with any latex formulation used in carpet reinforcement. Suitable additional fire retardants include, but are not limited to, metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphate salts, other phosphorus-containing compounds, aluminum trihydrate, and nitrogen-containing compounds, different from amino acids, proteins and / or peptides.

III. The Retarder Composition of Fire Used in the Modality C The fire retardant composition includes a crosslinking agent, as well as various other optional components, together with a suitable solvent. The crosslinking agent is covalently bound to the cellulosic material.

A. Crosslinking agents In this embodiment, suitable crosslinking agents include compounds with two or more reactive groups which are capable of reacting with the hydroxyl groups on the cellulosic materials, or reacting with the tosylate, mesylate, triflate or other leaving groups prepared from the hydroxyl groups on the cellulose materials. Suitable crosslinking agents include those described above in Modality B. In this embodiment, the crosslinking agents are used to covalently crosslink the hydroxyl groups on the cellulosic material. Preferably, a sufficient amount of crosslinking agents is present to covalently crosslink at least a sufficient amount of hydroxyl groups on the cellulosic material, to make it fire resistant, sufficiently for the intended use. For cotton mats, a sufficient amount of crosslinking is typically between 0.12 and 2.0 percent of the hydroxyl groups on cotton.

B. Phosphorus-Based Compounds The crosslinking agents that cross-link the cellulosic substrate can also cross-link the substrate with phosphorus-based compounds. As used herein, "phosphorus-based compounds" are compounds that include a phosphorus atom and that are capable of being covalently linked to a crosslinking agent and / or a cellulosic substrate. The numerous phosphorus-based compounds are known for their flame retardant properties. Any phosphorus-based compound that is capable of being cross-linked with a cellulosic substrate by means of a cross-linking agent as described herein, may be used. Preferably, the phosphorus-based compounds include one or more reactive groups that can react with the crosslinking agent. Examples of suitable groups include halogen, hydroxyl, carboxylic acid, aldehyde and amide. Suitable phosphorus-based acids include phosphorous acid, hypophosphroso acid, and polyphosphoric acid, and also include hypophosphites and mono- and diacid alkali metal phosphates. Examples of other phosphorus-based examples include (di) phosphonium halide, dialkyl 1-amino-1-deoxyglucityl phosphonates, phosphorus amides, amino-polyhydroxyalkyl phosphonic acid, phosphonitrile chloride, phosphorimide chloride, tris phosphates ( haloalkyl), haloalkyl phosphates, dihydroxyalkyl phosphite, dialkylphosphonoalkane amide, bis (haloalkyl) haloalkyl phosphonate, (mercapto) phosphonitrilate, phosphonic esters of N-hydroxyalkyl, bis- (hydroxyalkyl) -phosphinic acid, tetrakis- (a -hydroxyalkyl) -phosphonium, aryl-haloalkyl phosphonate, hydroxyalkyl phosphonium salts, tri (polyhaloaryl) phosphate, halogenated phosphorothioates, phosphorus polyamides, phosphonitrile halides, bis- (hydroxypolyalkoxyalkylaminoethyl) phosphonates, where the polyalkoxy is substituted haloalkyl, phosphonates of amino-epoxy, and n-substituted derivatives including polyphosphonates, N-hydroxymethyl-3-phosphonopropionamide, haloalkyl or hydroxyalkyl halide -alyl-phosphonium, haloalkylphosphine oxide, haloalkylphosphinic acids, tetrahydroxydiphosphorin dioxide, tris (2-chloroethyl phosphate), tris (l-chloro-2-propyl) phosphate, tris (1,3-dichloro-2-phosphate) propyl), 2-bromoethyl-2-chloroethyl-3-bromopentyl phosphate, tetrakis (2-chloroethyl) ethylene diphosphate, bis (2-chloroethyl) 2-chloroethyl-phosphonate, oligomeric phosphonate phosphate, chloroethyl-ethylene phosphate oligomeric, tris (3-hydroxypropyl) -phosphine oxide, isobutylbis (3-hydroxypropyl) -phosphine oxide, and bis (2-chloroethyl) -vinyl phosphonate.

In a preferred embodiment, the phosphorus-based compound is fixed on the cellulosic substrate by reaction with maleic acid or other dicarboxylic or polycarboxylic acid and sodium phosphate, or sodium hypophosphite. As used herein, the term "alkyl" refers to straight, branched or cyclic monovalent groups preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms ("lower alkyl") and most preferably 1 to 6 carbon atoms . This term is exemplified by groups such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, n-hexyl and the like. In those cases where the minimum number of carbons is greater than one, for example, alkenyl (minimum of two carbons) and cycloalkyl (minimum of three carbons), it is understood that "lower" means at least the minimum number of carbons. As used herein, "aryl" refers to an unsaturated aromatic carbocyclic group of 6 to 14 carbon atoms that has a single ring (e.g., phenyl) or multiple fused rings (fused) (for example, naphthyl or anthryl). Preferred aryls include phenyl, naphthyl and the like. Unless otherwise restricted by the definition for the aryl substituent, such aryl groups may optionally be substituted with 1 to 5 substituents and preferably 1 to 3 substituents selected from the group consisting of hydroxyl, acyl, alkyl, alkoxy, alkenyl, alkynyl, substituted alkyl, substituted alkoxy, substituted alkenyl, substituted alkynyl, amino, substituted amino, aminoacyl, acyloxy, acylamino, alkaryl, aryl, aryloxy, azido, carboxyl, carboxyalkyl, cyano, halo, nitro, heteroaryl, heteroaryloxy, heterocyclic, heterocycloxy, aminoacyloxy, oxyacylamino, thioalkoxy, substituted thioalkoxy, thioaryloxy, thioheteroaryloxy, and trihalomethyl. Preferred substituents include alkyl, alkoxy, halo, cyano, nitro, and trihalomethyl. As used herein, the terms "halo" or "halogen" refer to fluorine, chlorine, bromine and iodine, and preferably to bromine or chlorine. The terms "haloalkyl" and "haloaryl" refer to alkyl and aryl groups substituted with 1 to 5, preferably 1 to 3, halogen groups. The phosphorus-based compounds are preferably linked to the crosslinking agent, which in turn is crosslinked with the cellulosic substrate. The means for linking the phosphorus-based compounds and the cross-linking agents described herein are well known to those skilled in the art.

In one embodiment, the phosphorus-based compounds are coupled by means of a cross-linking agent to a cellulosic substrate through the formation of the phosphate ester bonds with the phosphoric acid groups on the phosphorus-based compounds, and a first reactive group on the crosslinking agent, and a second reactive group on the crosslinking agent is reacted with the cellulosic substrate. In those embodiments in which the phosphorus based compounds are used, the resulting cellulosic substrate can be sufficiently fire retardant for use in end uses that require flame retardant finishes. Examples of such end-uses include protective clothing (eg, clothing for foundry workers and uniforms for firefighters), children's sleepwear, furniture / upholstery, bedding, carpets, curtains and tents. For all these end uses of fabric, the chemicals can be applied, for example, by padding at 50-150 percent moisture pickup, preferably between 70 and 100 percent moisture pickup. However, other application techniques may also be used.

C. Solventee Adecuadoe Preferably, the crosslinking agent together with any compounds based on phosphorus, are present in an aqueous solution, euepeneion or dispersion. Other volatile compounds may be used which are inert to the coupling chemistry and in which the material is soluble or uniformly dielectable.

D. Optional Components Additional components may optionally be added to the fire retardant composition. These include, but are not limited to, other fire retardants, colorants, flame retardant agents, defoaming agents, cushioning agents, pH stabilizers, fixing agents, stain repellents such as fluorocarbons, stain blocking agents, repellents. to the dirt, agents, humectants, softeners, water repellents, manche release agent, optical brightener, emulsifier and eurfactantee. In one embodiment, the cellulosic substrate is a carpet. When other fire retardants are used in the carpets, these may be present in or on the carpet fiber or the reinforcing material. If a fire retardant is present in the reinforcement layer, the fire retardant is preferably a material. which is activated at a lower temperature than alumina trihydrate. Preferably, formaldehyde or other volatile organic compounds are not released from the reinforcing layer. In addition, fire retardants are preferably compatible with any latex formulation used in carpet reinforcement. Suitable additional fire retardants include, but are not limited to, metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphate salts, other phosphorus-containing compounds, aluminum trihydrate, and compounds containing nitrogen.

IV. Cellulose substrates Any cellulosic substrate that includes hydroxyl groups can be treated with the above compositions. Cotton is a preferred cellulosic fiber. Other cellulosic fibers include flax, jute, hemp, Tencel, Lyocell, ramia and unsubstituted, regenerated wool celluloses, such as rayon. The material can be a mixture of fibers, such as a mixture of cotton and a polyolefin such as polypropylene, a polyester or polytrimethyl terephthalate (PTT). The fiber composition is preferably at least 25, and more preferably, at least 40 weight percent cotton. Any density of carpet area, garment with raised surface and light weight, or other woven, non-woven or knitted fabrics, can be constructed or used, which is practical from a manufacturing point of view.

V. Articles of Manufacture Prepared from the Composition The treated fiber compositions can be used for various purposes, including cotton rugs, raised and lightweight garments, articles of clothing, etc. Cotton rugs are a preferred article of manufacture. The high-surface and lightweight garments are also preferred articles of manufacture. When used in carpets, the yarn in the carpet has an area density of between 678 g / m2 (20 ounces / square yard) and 4068 g / m2 (120 ounces / square yard), more preferably between 1017 g / m2 ( 30 ounces / square yard) and 2712 g / m2 (80 ounces / square yard).

SAW . Methods of Manufacturing Fire Retardant Compositions The compositions described herein are either commercially available or can be prepared using known methodology. These can be added to a desired solvent at a desired amount, to form a desired concentration and form a fire retardant solution.

VII. Methods of Treatment of the Cellulose Substrate The methods described herein involve the addition of one or more fire retardant compositions, described herein, to a cellulosic substrate, and reacting the composition with the substrate. The solutions including the fire retardant compositions described herein are added in any suitable ratio, but preferably, the amount of the solution is between 1.0 and 200 weight percent of the fiber to be treated, more preferably between 5.0 and 100 weight percent, and most preferably between about 15 and 80 percent. The above ranges vary depending on the mode of application and the cellulosic substrate to be treated. For example, when the composition is applied by spray, foam or other low moisture pickup methods commonly used for the treatment of carpets with fluorochemical products, the percentage by weight of the fire retardant solution that is applied to the cellulosic substrate is typically between 5 and 100 weight percent, preferably between about 10 and 50 weight percent, and more preferably, between about 15 and 30 weight percent of the fiber to be treated. For high-weight and light-weight garments, larger amounts of the fire retardant solution may be required to achieve adequate fire resistance. The same general principle of adjusting the concentration of the solution based on the addition of total moisture, applies to other substrates as well, such as fiber filling, upholstery, children's sleepwear, bedding, wadding, clothing protective and curtains. An amount of about 15 weight percent of the bath on the carpet is particularly well suited for spray application, foam application and other moisture harvesting methods commonly used to treat carpets with fluorochemical products. The use of these methods and types of solutions helps to avoid the addition of excess water that will have to be removed during drying. After the composition is adequate and the excess water is removed, the material is typically heated to a sufficient temperature and for a sufficient time to remove the solvent and / or react at least a portion of the functional groups (reactants) in the fire retardant composition, with the groups on the cellulose substrate. For example, in Modality A, and with some cross-linking agents in Modalities B and C, all or a portion of the hydroxyl groups on the material are esterified. With respect to Modality C, the functional groups (reactants) on the fire retardant composition also react optionally with the phosphorus-based compound. The material can then be optionally rinsed to remove residual chemicals without reacting, and then it dries. For carpets, there is a variety of application techniques that can be used to apply fire retardant solutions. These include spraying, foaming, immersion, soaking, dripping, cascading, liquor circulation all along the substrate, padding or caulking, clamping rollers and scrapers. These techniques can be used alone or in conjunction with vacuum, squeezing rollers, centrifugation, air blades, drainage by gravity or other techniques. The application can be carried out by means of a continuous or batch method. The composition can also be applied by other application techniques, including by application by discharge. In a discharge application the liquor ratio may vary over a wide range from about 2 to 1 to about 50 to 1. More preferably about 3 to 1 to about 20 to 1, which means about 20 kilograms of the treatment solution per kilogram of substrate containing cellulosic material. In a preferred embodiment, the proportion of the liquor is about 10 to 1 and the concentration of the crosslinking agent is adjusted accordingly to a concentration in the range of 0. 001 percent up to about 5.0 percent and I I preferably from about 0.01 to 1.0 percent in I weight of the liquor; treatment that is equivalent to 0.1 per 100% to 10.0 weight percent of the cellulosic substrate. I With respect to Modes B and C, wet crosslinking agents, which can also be applied by discharge techniques from the same bath, can be applied with phosphorus-based compounds to provide covalent bonds that result in treatments which are durable for various cleaning techniques. A wet crosslinking agent of this type is known as T-DAS, a d-chlorotriazine crosslinking agent. As with the spray and foam application I described above, the crosslinking agent may appear in the dry state after the excess water I has been removed or in the wet state, before the excess water is removed. .

The application (s) of fire retardant solutions can be made to the fiber, to the threads or to the carpet, either before, after or in conjunction with other processing or manufacturing steps, such as dyeing, winding, wiring, heat hardening, accreting, knitting or knitting. For high-weight and lightweight garments, or any other garment that can benefit from a reduction in flammability, the application can be made by any of the aforementioned techniques in the form of fibers, yarns, fabrics or garments. To wear. Spraying, defoaming, immersion or the "Dosing Addition Process" are particularly suitable for application in garments. The total amount of the solution added to the substrate and the required concentration of the reactive components, for example, carboxylic acids, amino acids, proteins, peptides, crosslinking agents and phosphorus-based compounds, in the solution, will be dependent on many factors, including the flammability test method, the weight and construction of the substrate, and the mixing levels of many possible fibers in a mixture.

Suitable reaction times are typically between about one minute and five hours. However, the reaction times relate in part to the pH of the fire retardant solution and, with respect to Modality A, the pKa of the particular carboxylic acid used. At a pH of less than 11 for the hydroxyl, thiol and amine groups, or greater than 4 for the carboxylic acids such as maleic acid, the cure times are generally longer. However, there seems to be less of a change in shade of dye from stained carpets when a pH greater than 4 is used. Carpets typically have a polypropylene reinforcement layer, which tends to melt or shrink at temperatures above. 150 ° C. for this reason, it is preferable that this temperature is not exceeded when this type of carpet is treated. However, high-weight and light-weight garments, upholstery, fiber fill and non-thermoplastic reinforcement mats can not have this type of temperature limitation. When these types of substrates are treated, the reaction temperature can be elevated as required, consistent with the surface burn and / or yellowing temperatures of these materials. A person skilled in the art can easily determine an appropriate set of temperatures for a particular substrate to be treated. Those of skill in the art can easily determine an appropriate set of reaction conditions (amount of the fire retardant solution to be added and temperatures and suitable reaction times) to form the appropriate bonds, for example, in Modality A, the bonds ester, between the cellulosic substrate and the flame retardant composition.

Modality A With respect to Modality A, at least a portion of the hydroxyl groups on the cellulosic substrate and at least a portion of the carboxylic acid groups on the acid are covalently linked in an esterification reaction. The esterification conditions involve the application of an appropriate amount of the composition to a cellulosic substrate and the heating of the substrate at a sufficient temperature for a sufficient time to crosslink an effective amount of the hydroxyl groups on the cellulosic substrate, to impart fire retardance. suitable for the intended use of the substrate.

Preferably, the substrate is heated to a temperature between about 100 and 200 ° C for between 15 and 30 minutes. While not wishing to be limited to a particular theory, it is believed that chemistry involves the production in itself of anhydrides, which then react with the hydroxyl groups on the cellulosic substrate. The in-situ production of anhydrides from an aqueous solution of carboxylic acids is preferable for using anhydrides in a non-aqueous solution, since this avoids the use of non-aqueous solvents. Since the carboxylic acids typically used do not provide the carpet with odor or toxicity, subsequent rinsing can not be desired. In addition, any unreacted carboxylic acid or other functional groups can be used to couple to other types of molecules, for example, through the formation of the ester or amide bonds. Since phosphorus-based catalysts are not present, the amount of esterification is relatively low when using phosphorus-based catalysts. This is advantageous since only a relatively low degree of esterification is required to render the cellulosic materials fire resistant, while a relatively high degree of esterification is required to make the materials resistant to wrinkles.

The concentration of the carboxylic acid required to be effective, based on the weight of the solution and on the weight of the substrate, will be dependent on the above-mentioned factors for all substrates, including high-surface and light-weight garments, carpets, upholstery, and any other substrate where it is desirable to reduce flammability. Any of the application techniques mentioned above, or which are used to apply other chemical treatments to fibrous substrates, are considered appropriate for use herein for any cellulosic substrate where flammability is desired to be reduced. While the proportions of liquor bath treatment or solutions are greater than 1: 1 (eg, greater than one kilogram (pound) of treatment solution per kilogram (pound) of substrate), pretreatment techniques, such as the cationic pre-treatments can be used to stimulate the treatment chemicals, for example: carboxylic acids, to discharge or move out of the solution and onto the cellulosic substrate. Although the temperature required to effectively form the ester linkages could be expected to vary to some degree depending on the nature of the substrate to be treated and the anhydride, a typical temperature range is between about 100 and 240 ° C, more preferably between 110 and 200 ° C. The temperature is preferably lower than what could otherwise be required to surface burn the substrate. Excessive heating can cause yellowing of the substrate fibers, so care must be taken to control the reaction temperatures. In those embodiments in which the carboxylic acid-containing compounds include carbon-carbon double bonds, these bonds can be polymerized before, simultaneously with or after the formation of the ester bonds with the hydroxyl groups on the cellulosic substrate. Methods for the polymerization of carbon-carbon double bonds are well known to those skilled in the art, and typically involve the addition of a free radical polymerization initiator, such as tert-butyl peroxide, persulfates, or azobisisobutyronitrile ( AIBN).

Mode B With respect to Modality B, at least a portion of the hydroxyl groups on the cellulosic substrate and at least a portion of the reactive functional groups on the amino acid, the protein and / or the peptide and the crosslinking agent, are covalently linked. The reaction conditions involve the application of an appropriate amount of the composition to a cellulosic substrate, and the heating of the substrate at a sufficient temperature for a sufficient time to crosslink an effective amount of the hydroxyl groups on the cellulosic substrate, to impart a delay of the cellulose. fire suitable for the intended use of the substrate. Methods for covalently linking a hydroxyl group such as those on a cellulosic substrate and a hydroxyl, thiol, amino or carboxyl group, such as those on an enzyme, are well known to those skilled in the art. Conventional means involve the use of crosslinking agents, preferably those that do not contain formaldehyde and other toxic substances. The preferred methods are those that can be carried out in aqueous solvents. In one embodiment, the amino acids, proteins and / or peptides are applied by application by discharge. In a discharge application the liquor ratio can vary over a wide range from about 2 to 1 to about 50 to 1. More preferably about 3 to 1 to about 20 to 1, which means that about 20 kilograms of the treatment solution per kilogram of the substrate that contains the cellulosic material. In a preferred embodiment the proportion of the liquor is about 10 to 1, and the concentration of the amino acid, the protein and / or the peptide is adjusted accordingly to a concentration range of 0.001 percent to about 5.0 percent, and preferably from about 0.01 to 1.0 weight percent of the treatment liquor which is equivalent to 0.1 percent to 10.0 weight percent of the cellulosic substrate. Any unreacted functional groups on the amino acids, proteins and / or peptides, such as the hydroxyl, thiol, amine or carboxylic acid groups, can be used to couple other types of molecules, for example, through the formation of ester bonds or amide. Where the proportions of the liquor from the bath or treatment solution are greater than 1: 1 (eg, greater than one kilogram (pound) of treatment solution per kilogram (pound) of the substrate), pretreatment techniques, such as pre-treatment Cationic treatments can be used to promote the treatment chemicals, for example, the crosslinking and / or coupling agents, to be discharged or released from the solution and onto the cellulosic substrate. Although the temperature required to form the bonds in a required manner could be expected to vary to some extent depending on the nature of the substrate to be treated and the amino acid, protein and / or peptide, a typical temperature range is between about 20 and 240 ° C, more preferably between 40 and 200 ° C. The temperature is preferably lower than what could otherwise be required to surface burn the substrate. Effective heating can cause yellowing of the fibers of the substrate, so care must be taken to control the reaction temperatures. The coupling and / or crosslinking agents which will react with the amino acid, the protein and / or the peptide and the cellulosic material in the wet state, can be used to achieve fixation or reaction in the dyeing equipment used to dye the substrates cellulose It can be difficult to prepare anhydride in itself when using amino acids, proteins and / or peptides that contain only one carboxyl group. For these materials, it may be desirable to use conventional chemistry, such as the formation of acid halides or anhydrides and the application of these materials to the carpet, instead of forming anhydrides therein.

Modality C With respect to Modality C, at least a portion of the hydroxyl groups on the cellulosic substrate and at least a portion of the reactive functional groups on the crosslinking agent are covalently linked. The reaction conditions involve the application of an appropriate amount of the composition to a cellulosic substrate and the heating of the substrate at a sufficient temperature, for a sufficient time, to crosslink an effective amount of the hydroxyl groups on the cellulosic substrate, to impart delay of fire suitable for the intended use of the substrate. Methods for covalently linking a hydroxyl group such as those on a cellulosic substrate and the reactive groups present on a crosslinking agent are well known to those skilled in the art. Preferably, the crosslinking agents do not contain formaldehyde or other toxic substances. The preferred methods are those that can be carried out in aqueous solvents.

The material can then be optionally bonded to remove unreacted residual chemicals, and then dried. However, since crosslinking agents typically do not provide the carpet with odor or toxicity, subsequent rinsing may not be desired. In addition, any unreacted functional groups on the crosslinking agents can be used to couple other types of molecules, through the formation of ester or amide bonds. Examples of such molecules include fluoroalkyl compounds commonly used to impart stain resistance properties to carpets and other textile materials. The concentration of the crosslinking agent or agents required to be effective, based on the weight of the solution and the weight of the substrate, will depend on the above-mentioned factors for all substrates, including the high-surface garment and of desired weight, carpets, upholstery, and any other substrate where it is desirable to reduce flammability. Any of the application techniques mentioned above, or which are used to apply other chemical treatments to the fibrous substrates, are considered suitable for being used herein for any cellulosic substrate where flammability is desired to be reduced. Where the proportions of the liquor of the bath or treatment solution are greater than 1: 1 (eg, greater than one kilogram of treatment solution per kilogram of the substrate), pre-treatment techniques, such as cationic pre-treatments may be used to promote or strengthen treatment chemicals, for example, crosslinking agents and / or phosphorus-based compounds, to be discharged or released from the solution and onto the cellulosic substrate. Although the temperature required to effectively form the bonds could be expected to vary somewhat depending on the nature of the substrate to be treated and the crosslinking agent (s), a typical temperature range that is between about 20 and 240 ° C, more preferably between 40 and 200 ° C. The temperature is preferably lower than what could otherwise be required to surface burn or melt the thermoplastic components of the substrate. Excessive heating can cause yellowing of the substrate fibers, so care must be taken to control the reaction temperatures. The crosslinking agents that will react with the cellulosic material and, optionally, the phosphorus-based compound, in the wet state can be used to achieve fixation or reaction in the dyeing equipment used to dye the cellulosic substrates. The fire retardant compositions in Modalities C may also be used to prepare protective clothing (eg, clothing for foundry workers and uniforms for firefighters), children's sleepwear, furniture / upholstery, bedding, carpets, curtains and tents. There are a variety of application techniques that can be used to apply fire retardant solutions to these substrates. These include immersion, soaking, dripping, cascading, circulating liquor all along the substrate, padding or padding, clamping rollers, and doctor blades. These techniques can be used alone or in conjunction with vacuum, squeezing rolls, centrifuge, air blades, gravity draining or other techniques. The application can be carried out by means of a continuous or batch method.

VIII. Composition Evaluation Methods Fire Retardant Cellulosics The adequacy of the fire retardant composition for a intended use will depend on the ability of the treated cellulosic substrate to pass various standard flammability tests. The currently accepted test for carpets is the pill test. The currently accepted test for high surface garments is the 45 degree angle test. The test protocol for these tests is well known to those skilled in the art. Using these tests, with a properly prepared, flammable cellulosic fiber composition, the effectiveness of the fire retardant composition for its intended use can easily be determined. The present invention will also be understood with reference to the following non-limiting examples.

Example 1: Use of Maleic Acid without Catalysts Based on Phosphorus, to Reduce the Flammability of the Carpet The purpose of this experiment was to assess whether maleic acid without a phosphorus catalyst will provide sufficient fire retardancy to allow cotton carpets to pass the fiber test. Samples of carpets treated with maleic acid without a catalyst or with sodium hydroxide passed the pill test after 10 household washes (HL). When potassium acetate was used to catalyze the reaction, the flammability results were only marginal, for example, one sample passed and one failed. The same marginal result was noticed when a resin without formaldehyde (Freerez NFR, Freedom) was applied to try to crosslink the acid to the cotton. Sodium bicarbonate did not work as a catalyst for this reaction.

Experimental procedure: Aqueous solutions of maleic acid, with or without added catalyst, were sprayed wet on dry on CD98-054-1 carpet (75% cotton / 25% bicomponent polyester, gauge 3.17 mm (1/8 inch), 3.54 points per centimeter (9 points per inch) (psi), hair cut to 16.66 mm (21/32 inch) (1356 g / m2 (40 ounces / square yard)) at 15% objective addition. The bicomponent polyester is a shell / core fiber with low melting polyester as the shell and "regular" polyester as the core. Two series of experiments were run, the 55 series and the 65 series. The amount of maleic acid and catalyst that was sprayed onto the carpet is shown in Table I. In the 55 series, the fluorochemical (Scotchgard FX-1367, 3M) (5% by weight of the bath ("owb")) and the wetting agent (Alkanol 6112, Ciba Specialty Chemicals) (0.2% owb) were included in all the baths, except the control (water). In the 65 series, only the wetting agent (0.2% owb) was included in the baths, except for 65/6, which was a control. Sodium perborate (2% owb) was added to 65/2 to improve whiteness. All samples were dried at 104 ° C (220 ° F) or 25 minutes. Specimens 55 / 1-3 and 65 / la were cured for 5 minutes at 138 ° C (280 ° F). The remaining pieces were cured at 121 ° C (250 ° F) for 5 minutes.

TABLE I Treatment Formulations The concentrations are given as percentage by weight of the liquor xowb = weight of the carpet.

-"*"•-"- • Results and Discussion After 10 domestic washes (HL), two specimens of 12.7 x 12.7 cm (5 inches x 5 inches) of each of the runs were subjected to the pill test, with the exception of run 65/2, which had four tested specimens. The pill test was conducted in accordance with the Code of Federal Regulations (CFR) title 16, part 1630 test method (Code of Federal Regulations, Title 16 Part 1630, page 632 (1995)). The results given in Table II show that, in the 55 series, the sample treated with maleic acid and without a catalyst had two specimens that passed the pill test. Nevertheless, some yellowness and rigidity was present. In order to overcome the yellowing, sodium perborate was added to the maleic acid solution (65/2) to act as a bleaching agent. The four specimens and two others (65 / 1B) that were cured at the same temperature passed the pill test. A lower cure temperature was chosen as another means to reduce yellowing. There was no significant difference in color between the samples with perborate in the formulation and those without perborate. All these samples had only one very • ** iUi? I £ _UÜ_á * & a ^^ slight change of color with respect to the control. Specimen 65 / 1A, which was cured at 138 ° C (280 ° F) also had an acceptable color. The solution used to treat sample 55/2 included bicarbonate, and showed effervescence due to disintegration to produce C02 while the solution was being mixed. This sample failed the pill test. The use of potassium acetate as a catalyst worked only marginally. The amount of potassium acetate used in 65/4 brought the pH of the solution to 2.0. As the pH increases, the acid groups are converted to carboxylate (salt) groups that are less reactive. The pH of 65/3, using sodium hydroxide as a catalyst, was 1.7. Both 65/3 specimens passed the pill test. Although sodium hydroxide converted some of the maleic acid to sodium maleate, enough acidic groups remained reacting with the carpet. The incorporation of the resin in the finish to fix the flame retardant to cotton was not successful.

TABLE II Appearance and Flammability Test Results 1 Pass = both specimens passed. Fail = both specimens failed. 1P / 1F = 1 passed 1 failed. NT = not tested.

Conclusions Sodium bicarbonate and sodium acetate were not good catalysts for the reaction of maleic acid with cotton. The absence of the catalyst and a catalytic amount of sodium hydroxide worked equally well to produce carpets that passed the pill test.

Example 2: Evaluation of Reticulators for the Fixation (Union) of a Flame Retardant (FR) Based on Phosphorus at a Low Healing Temperature Summary Two modified ethyleneurea resins (EU) produced a reasonable fixation of the phosphorus based FR agent on cotton mats. The percent fixation after ten (10) household washes was in the same range as the original reagent, the FR agent based on phosphorus.

Introduction A phosphorus-containing (FR) finish can provide reduced flammability of cotton carpets. In order to make this finish durable to the ten washes required by federal regulations, a crosslinker was used to attach this FR finish to cotton. objective The curing time was evaluated with a crosslinking resin. Several resins were applied under the same curing conditions to compare the effectiveness of each as a crosslinker for the FR.

Experimental procedure TABLE III shows the formulations that were sprayed on a low melting cotton / Foss 90/10 polyester carpet, CD-98-026 (cut pile, 1/8 inch gauge, 3.54 points) per cm (9 points per inch (SPI), hair height of 6.56 mm (21/32 of an inch), 1356 g / m2 (40 ounces / square yard) to an addition of 15% of the objective.) Effective application levels are given in TABLE IV All specimens were dried at 104 ° C (220 ° F) for fifteen minutes Samples 1 and 5 were cured for five minutes at 121 ° C (250 ° F), while the remaining samples (2-4 and 6-8) were cured for 20 minutes at the same temperature The pill tests were performed on two pieces of 12.7 x 1.7 cm (5 x 5 inches) before the laundry (HLTD), after 1 HLTD and after 10 HLTD The phosphorus analysis (P) was performed by ICP-OES at Galbraith Laboratories.

TABLE III Formulations (The concentrations are given as% by weight of the liquor) - • - * • * 1 Sample 7 contained the standard FR (control).

TABLE IV Objective and Effective Carpet Weights and Levels of Application (5 addition) owc = Weight of the Carpet Results and Discussion As indicated by the results of TABLES V and VI, the samples that were cured for a longer time and were treated with higher concentrations of FR and crosslinker had poorer hand than the control samples. Healing for a shorter time may allow acceptable hand. At a FR / crosslinker concentration of 1.50 / 1.50% owc, all samples passed the pill test, even after 10 household washes.

TABLE V Appearance and Flammability Test Results Pass = both specimens passed. Fail = both specimens failed. 1P / 1F = 1 passed 1 failed. HL = Domestic Laundry.

Modified EU-type resins are preferred over PCA resins for FR crosslinking. 0 TABLE VI Results of Phosphorus Analysis The FR agent, in conjunction with the crosslinking chemistry is effective in reducing the flammability of the cotton carpet.

Product identification Modifications and variations of the methods and compositions described above will be obvious when considering the description of the invention. It is intended that such modifications be within the scope of the claims.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention is that which is clear from the present description of the invention.

Claims (71)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A method for preparing cellulosic fiber with reduced flammability, characterized in that it comprises: a) The preparation of a composition comprising carboxylic acids, but which does not include an esterification catalyst based on phosphorus or an alkoxide catalyst; b) the application of an effective, flame-retardant amount of the composition to a substrate to be treated, comprising a cellulosic fiber or a mixture of a cellulosic fiber with another fiber; and c) esterification of the carboxyl groups with a sufficient amount of the hydroxyl groups on the fiber to be treated, such that the resulting treated fiber has an acceptable degree of fire resistance for the intended use.

2. The method according to claim 1, characterized in that the carboxylic acid-containing composition comprises a straight chain, branched or cyclic alkane of 2 to 20 carbon atoms that includes at least a carboxylic acid moiety, and which is optionally substituted with a functional group selected from the group consisting of carbon-carbon double bonds, halides, perfluorinated groups, amines, phosphorus esters, monosaccharides, polysaccharides, imides and amides.

The method according to claim 1, characterized in that the carboxylic acid-containing composition includes an acid selected from the group consisting of maleic acid, malic acid, tartaric acid, succinic acid, citric acid, and maleic acid / acid copolymers acrylic.

4. The method according to claim 1, characterized in that the degree of substitution on the cellulosic substrate is between about 0.003 to 0.5.

5. The method according to claim 1, characterized in that the degree of substitution on the cellulosic substrate is between about 0.005 to 0.025.

6. The method according to claim 1, characterized in that the fiber is a cotton fiber.

The method according to claim 6, characterized in that the cotton is in the form of a cotton rug.

The method according to claim 6, characterized in that the cotton is present in garments of high surface area or of light weight.

The method according to claim 1, characterized in that the fiber is a mixture of cotton and another fiber selected from the group consisting of polyesters, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins, Tencel®, and Lyocell.

The method according to claim 1, characterized in that the composition further comprises a component selected from the group consisting of other fire retardants, colorants, wrinkle-resistant agents, defoaming agents, buffers, pH stabilizers, fixing agents, stain repellents, stain blocking agents, dirt repellents, wetting agents, softeners, water repellents, stain release agents, optical brighteners, emulsifiers and surfactants.

The method according to claim 1, characterized in that the fiber is selected from the group consisting of Lyocell ™, Tencel® and rayon.

The method according to claim 1, characterized in that it further comprises a dyeing step before or subsequent to the esterification step.

13. A carpet comprising cotton fiber, characterized in that a portion of the hydroxyl groups on the cotton fiber have been esterified with a carboxylic acid-containing portion.

The carpet, according to claim 13, characterized in that the carboxylic acid-containing portion is a straight-chain, branched or cyclic alkane having from 2 to 20 carbon atoms which includes at least one portion of carboxylic acid, and which is optionally substituted with a functional group selected from the group consisting of carbon-carbon double bonds, halides, amines, phosphorus esters, monosaccharides, disaccharides, polysaccharides, imides and amides.

15. The carpet, according to claim 14, characterized in that the carboxylic acid-containing portion is selected from the group consisting of maleic acid, malic acid, tartaric acid, succinic acid, citric acid, and maleic acid / acrylic acid copolymers.

16. The carpet according to claim 14, characterized in that the degree of substitution on the cotton fiber is between about 0.003 to 0.5.

17. The carpet according to claim 14, characterized in that the degree of substitution on the cotton fiber is between about 0.005 to 0.025.

The carpet according to claim 14, characterized in that the carpet further comprises a second fiber selected from the group consisting of polyesters, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins , Tencel®, and Lyocell.

19. The carpet according to claim 14, characterized in that the carpet further comprises an additional fire retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts, trihydrate aluminum, and nitrogen-containing compounds.

20. A high-weight or light-weight garment characterized in that it comprises cotton fibers in which a portion of the hydroxyl groups on the cotton fiber have been esterified with a carboxylic acid-containing portion.

21. A method for preparing cellulosic fiber with reduced flammability, characterized in that the method comprises: a) the preparation of a composition comprising amino acids, proteins and / or peptides and a suitable cross-linking agent and / or coupling; b) the application of an effective, fire-retardant amount of the composition to a substrate to be treated, comprising a cellulosic fiber or a mixture of a cellulosic fiber with another fiber; and c) the linking of the hydroxyl, lime, amine and / or carboxylic acid groups on the amino acid, protein and / or peptide, with a sufficient amount of the hydroxyl groups on the fiber to be treated, such that the fiber The resulting treated has an acceptable degree of fire resistance for the intended use.

22. The method according to claim 21, characterized in that the amino acid, the "* -" - * - f protein, the peptide or the crosslinking agent is substituted with one or more functional groups selected from the group consisting of carbon-carbon double bonds, halides, perfluorinated groups, amines, phosphorus esters, monosaccharides , polysaccharides, imides and amides.

23. The method according to claim 21, characterized in that the degree of substitution on the cellulosic substrate is between about 0.003 to 0.5.

24. The method according to claim 21, characterized in that the degree of substitution on the cellulosic substrate is between approximately 0.005 to 0.025.

25. The method according to claim 21, characterized in that the fiber is a cotton fiber.

26. The method according to claim 25, characterized in that the cotton is in the form of a cotton rug.

27. The method according to claim 25, characterized in that the cotton is present in garments of high surface or light weight.

The method according to claim 21, characterized in that the fiber is a mixture of cotton and another fiber selected from the group consisting of polyesters, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins, Tencel®, and Lyocell. it further comprises an additional fire retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts, aluminum trihydrate, and nitrogen-containing compounds.

29. The method according to claim 21, characterized in that the fire retardant composition further comprises an additional fire retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts. , aluminum trihydrate, and nitrogen-containing compounds.

30. The method according to claim 21, characterized in that the composition further comprises a component selected from the group consisting of other fire retardants, colorants, wrinkle resistant agents, defoaming agents, buffers, pH stabilizers, fixing agents, repellents to stains, stain blocking agents, dirt repellents, wetting agents, softeners, water repellents, stain release agents, optical brighteners, emulsifiers and surfactants.

31. The method according to claim 21, characterized in that the fiber is selected from the group consisting of Lyocell ™, Tencel® and rayon.

32. A method for preparing cellulosic fiber with reduced flammability, characterized in that it comprises: a) the selection of a suitable cellulosic substrate, b) the pretreatment of the substrate with a cationic pretreatment, c) optionally removing the excess pretreatment, d) adding a effective amount of the fire retardant of a composition comprising amino acids, proteins and / or peptides, and optionally including a suitable crosslinking agent and / or a coupling agent to the pretreated substrate, and e) optionally linking the hydroxyl, thiol, amine groups and / or carboxylic acid on the amino acid, the protein and / or the peptide, with a sufficient amount of the hydroxyl groups on the fiber to be treated, such that the resulting treated fiber has an acceptable degree of fire resistance for the intended use, where the weight ratio of the solution to the substrate is greater than 1: 1.

The method of conformity with the Claim 32, further characterized in that it comprises a dyeing step in conjunction with or before the pretreatment step.

34. A carpet, characterized in that it comprises the cotton fiber in which a portion of the hydroxyl groups on the cotton fiber has been bound, directly or through a crosslinking agent, with an amino acid, protein and / or peptide.

35. The carpet according to claim 34, characterized in that the protein is an enzyme.

36. The carpet according to claim 34, characterized in that the degree of substitution on the cotton fiber is between about 0.003 a? .5.

37. The carpet according to claim 34, characterized in that the degree of substitution on the cotton fiber is between about 0.005 to 0.025.

38. The carpet according to claim 34, characterized in that the carpet further comprises a second fiber selected from the group consisting of polyester, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins, Tencel ®, and Lyocell.

39. The carpet according to claim 34, characterized in that the carpet further comprises an additional fume retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts, trihydrate aluminum, and nitrogen-containing compounds.

40. A garment of high surface or light weight, characterized in that it comprises cotton fiber in which a portion of the hydroxyl groups on the cotton fiber has been covalently bonded, directly or by means of a crosslinking agent, with an amino acid, protein and / or peptide.

41. The garment according to claim 40, characterized in that the protein is an enzyme.

42. A composition, characterized in that it comprises a cellulosic material in which between 5 and 100 percent of the hydroxyl groups on the material are covalently linked to an amino acid, protein and / or peptide, directly or through the use of a crosslinking agent or coupling.

43. A method for preparing cellulosic substrates with reduced flammability, characterized in that it comprises: a) the preparation of a composition comprising one or more cross-linking agents; b) the application of an effective, fire-retardant amount of the composition to a substrate to be treated, which comprises a cellulosic fiber or a mixture of a cellulosic fiber with another fiber; and c) linking the reactive groups on the crosslinking agent (s) with a sufficient amount of the hydroxyl groups on the fiber to be treated, such that the resulting treated fiber has an acceptable degree of fire resistance for the intended use .

44. The method according to claim 43, characterized in that the crosslinking agent (s) is (are) substituted with one or more functional groups selected from the group consisting of carbon-carbon double bonds, halides, perfluorinated groups, amines, phosphorus esters, monosaccharides , polysaccharides, imides and amides.

45. The method according to claim 43, characterized in that the degree of substitution on the cellulosic substrate is between about 0.003 to 0.5.

46. The method according to claim 43, characterized in that the degree of substitution on the cellulosic substrate is between about 0.005 to 0.025.

47. The method according to claim 43, characterized in that the fiber is a cotton fiber.

48. The method according to claim 47, characterized in that the cotton is in the form of a cotton rug.

49. The method according to claim 6, characterized in that the cotton is present in garments of high surface area or of light weight.

50. The method according to claim 43, characterized in that the fiber is a mixture of cotton and another fiber selected from the group consisting of polyester, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins, Tencel®, and Lyocell.

51. The method according to claim 43, characterized in that the fire retardant composition further comprises an additional fire retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts, trihydrate of aluminum, and nitrogen-containing compounds.

52. The method according to claim 43, characterized in that the composition further comprises a component selected from the group consisting of other fire retardants, colorants, wrinkle-resistant agents, defoaming agents, buffers, pH stabilizers, fixing agents, stain repellents, stain blocking agents, dirt repellents, wetting agents, softeners, water repellents, stain release agents, optical brighteners, emulsifiers and surfactants.

53. The method according to claim 43, characterized in that the fiber is selected from the group consisting of Lyocell ™, Tencel® and rayon.

54. The method according to claim 43, characterized in that the fire retardant composition further comprises a phosphorus-based compound.

55. The method according to claim 54, characterized in that the phosphorus-based compound is selected from the group consisting of vinyl phosphonate, bis (2-chloroethyl) vinyl phosphonate, tetrakis (2-chloroethyl) diphosphates, phosphate phosphonate oligomeric, and bis (2-chloroethyl) 2-chloroethylphosphonate.

56. A method for preparing cellulosic fibers with reduced flammability, characterized in that it comprises: a) selecting a suitable cellulosic substrate, b) pretreating the substrate with a cationic pretreatment, c) optionally removing the excess pretreatment, d) adding an effective delaying amount. of the fire of a composition comprising one or more crosslinking agents to the pretreated substrate, and f) optionally binding the reactive groups on the crosslinking agent (s) with a sufficient amount of the hydroxyl groups on the fiber to be treated, such that The resulting treated fiber has an acceptable degree of fire resistance for the intended use, wherein the weight ratio of the solution to the substrate is greater than 1: 1.

57. The method according to claim 56, characterized in that it comprises a dyeing step in conjunction with or before the pretreatment step.

58. The method according to claim 56, characterized in that the composition further comprises a phosphorus-based compound.

59. A carpet, characterized in that it comprises a cotton fiber in which a portion of the hydroxyl groups on the cotton fiber has been bonded with a crosslinking agent.

60. The carpet according to claim 59, characterized in that the crosslinking agent is a dimethyloldihydroxyethyleneurea, imidazole, imidazolidinone, dialdehyde or a dichlorotriazine.

61. The carpet according to claim 59, characterized in that the degree of substitution on the cotton fiber is between about 0.003 to 0.5.

62. The carpet according to claim 59, characterized in that the degree of substitution on the cotton fiber is between about 0.005 to 0.025.

63. The carpet according to claim 59, characterized in that the carpet further comprises a second fiber selected from the group consisting of polyesters, polyamides, polytrimethyl terephthalate (PTT), wool, acrylic, modacrylic, rayon, acetate, triacetate, polyolefins. , Tencel®, and Lyocell.

64. The carpet according to claim 59, characterized in that the carpet further comprises an additional fire retardant selected from the group consisting of metal oxides, metal carbonates, halocarbons, phosphorus esters, phosphorus amines, phosphorus salts, trihydrate aluminum, and nitrogen-containing compounds.

65. The carpet according to claim 59, characterized in that a portion of the hydroxyl groups on the cotton fiber has been linked, directly or through a crosslinking agent, to a phosphorus-based compound.

66. A high-weight or light-weight garment characterized in that it comprises cotton fiber in which a portion of the hydroxyl groups on the cotton fiber has been covalently bonded to the crosslinking agent.

67. The garment according to claim 66, characterized in that the agent is a dialdehyde or imidazolidone.

68. The garment according to claim 67, characterized in that a portion of the hydroxyl groups on the cotton fiber has been bound, either directly or by means of an agent of 5 cross-linking, to a phosphorus-based compound.

69. A composition, characterized in that it comprises a cellulosic material in which between 5 and 100 percent of the hydroxyl groups on the material are covalently bound with a crosslinking agent. 10

70. An article of manufacture, characterized in that it is selected from the group consisting of protective garments, children's sleepwear, upholstery, bedding, curtains, and tents comprising cotton fiber, wherein a portion of the groups The hydroxyl on the cotton fibers has been covalently bound to a crosslinking agent, and wherein a portion of the hydroxyl groups on the cotton fiber has been bound, directly or via a crosslinking agent, to a compound based on match.

71. The article of manufacture according to claim 70, characterized in that the crosslinking agent is a dialdehyde or imidazolidone. j ». «^ ^ A ^ fe ^ SUMMARY OF THE INVENTION The methods to make the cellulosic materials fire retardants, and the articles of manufacture that include the materials are described. The methods involve the application of a flame retardant composition to the material. In one embodiment, the composition includes a carboxylic acid-containing compound in the substantial absence of an esterification catalyst based on phosphorus, or a basic catalyst (eg, metal alkoxide). The material is heated to esterify at least a portion of the hydroxyl groups. In yet another embodiment, the compositions include an amino acid, protein and / or peptide and optionally include one or more crosslinking and / or coupling agents. Enzymes are a preferred protein. The methods involve the application of the composition to the material, and optionally involve the covalent linking of the amino acid, the protein and / or the peptide to the material, either directly or through a cross-linking agent. In a third embodiment, the compositions include one or more crosslinking agents, and, optionally, one or more phosphorus-based compounds. Dimethyloldihydroxyethyleneurea, imidazole, imidazolidinones, dialdehydes and dichlorotriazines are preferred crosslinking agents. The methods involve the application of the composition to the material, and the covalent bonding of the crosslinking agent to the material. One advantage of covalently binding the crosslinking agent to the cellulosic material is the lack of any potential toxicity associated with non-crosslinked flame retardants. on the cellulose material, and stabilized the bonds between the material and the crosslinking agent to conventional cleaning with steam and other methods of cleaning carpets. In a preferred embodiment, the fire retardant cotton fiber composition is used to prepare cotton carpets or lightweight, high surface garments. ^^^^^^^^