METHOD FOR FORMING COLORED CELLULOSE MATERIALS Field of the Invention The present invention relates to dyeing processes, and more specifically to methods for dyeing paper and other cellulosic materials. BACKGROUND OF THE INVENTION In many occasions, it is desirable to use a product of cellulosic material, such as paper, cardboard for boxes, cardboard and / or cardboard, which has a specific color for a particular use. For example, when decorating for a special occasion, streamers of various colors are often used to provide a festive appearance to the place where the occasion is being celebrated. To form products made from a cellulosic material and having a desired color, many different dyeing techniques have been used. Although many of these dyeing techniques provided adequate color to the cellulosic material that is dyed when finished, a significant problem remained in that the dye was frequently removed by washing or there was a color shift of the cellulosic material either during the dyeing process or when the material was put in contact with a liquid or simply by rubbing against another surface. To try to overcome the problem of the color shift, various compositions and methods of
Ref.153260 dyed different. For example, Reinhardt in U.S. Pat. No. 4,502,807 discloses a coloring matter that incorporates a thickener mixture that includes both a synthetic thickening agent and a polysaccharide. The presence of the thickener mixture with these components improved the ability of the dye to remain in the proper location on the textile material to which the dye was applied. In addition, Panto et al, in U.S. Pat. No. 4,398,915 discloses a method of preparing colored cellulose materials resistant to color shift using a colored particle such as a dye / starch complex formed as a reaction product of a starch with a reactive dye compound and a chemical crosslinking agent. . In addition, ieseether et al, in U.S. Pat. No. 5,384,585 describes the printing of textiles using a dye composition that includes a reactive dye and a methylcarboxymethyl cellulose as a thickener. However, these techniques, although initially providing the product of paper, cardboard for boxes, cardboard or paperboard with the desired color and an increased level of resistance to color shift or color migration, did not achieve the desired level of resistance to removal. of the colored dye from the product. As a result, the colored products are still produced, in which the color fades from the product, or in which the color can be removed from the product by wetting and / or rubbing a colored surface of the product. Therefore, it is desirable to develop a method for dyeing or otherwise coloring a cellulosic product in which the dye or color added to the product is highly resistant to the removal of the product. Brief Description of the Invention The present invention is an improved method for coloring products of cellulosic material in which the color is applied to the product in such a way that the color does not run and / or can not be easily removed from the product. The method or process involves two separate steps that achieve the desired result of application of color or dye to the product in such a way that the dye is highly resistant to removal. The first step in the method involves applying the colorant to the cellulosic substrate in any of several well-known application methods. The dye applied to the cellulosic substrate is formed as an aqueous solution of a thickener, a dye, and water. The thickener can be virtually any suitable material used to thicken and stabilize a dye composition, as will be described. Also, a wide range of dyes can be used in the dye formation, as will be described. The dye formed by the dye, the thickening agent and the water, can be any suitable dye used in the printing or dyeing of cellulosic and / or textile materials that is capable of being applied to the substrate in any of a number of application methods. of the conventional dye and that resists any dispersion or migration on the surface of the substrate after the application. In the second step, a coating material is applied to the substrate on the dye to form a protective film on top of the dye on the cellulosic material and increase the resistance to removal of the dye from the substrate. The coating material essentially provides a barrier between the colorant and any liquid and / or surface, which prevents contact with the colorant, whereby the colorant is maintained on the substrate. Detailed Description of the Invention The present invention is an improved method for the application of a colorant to a cellulosic substrate in a two-stage process which greatly improves the resistance to removal of the colorant on the substrate. Although the method is applicable to the application of a colorant or dye to virtually any number of different types of substrates, some of the preferred substrates that are capable of being used in this method include cellulosic substrates such as cardboard for boxes with the part white top, cardboard for boxes, and paper, among others. In a particularly preferred embodiment of the method of the invention, the substrate is a carton for boxes with the white top that is defined as a two-layer cellulosic web having a basis weight of 9.08 kg (20 pounds) up to 40.86 kg (90 pounds) per 92.9 m2 (1000 square feet). The base layer is comprised of a virgin material, recycled material or any combination thereof. The top layer of the cellulosic web is comprised of bleached or de-inked cellulosic fiber with a GE brightness of at least 60. Another preferred substrate is box carton which is defined as a two-ply cellulose web having a basis weight of 9.08. kg (20 pounds) up to 40.86 kg (90 pounds) per 92.9 m2 (1000 square feet). The base layer is comprised of a virgin material, recycled material or any combination thereof. The upper layer of the cellulose weft is comprised of recycled or virgin cellulose fiber. Still another preferred substrate is paper which is defined as a cellulosic web having a basis weight of 9.08 kg (20 pounds) up to 72.64 kg (160 pounds) per 278.7 m2 (3000 square feet). The web may also include filler materials that include, but are not limited to, clay, calcium carbonate, titanium dioxide, and / or sizing agents. When the dye is applied to the desired substrate, in the first stage, the dye is added to the substrate in a suitable dyeing or printing process, such as either a machine application for a different paper material, conventional, or an application. of machine on paper, including a glue press or water collector. Some suitable machine application processes for a material other than paper may include, but are not limited to, flexographic application, bar application, and / or processes using pneumatic knife coaters. The dye is more preferably comprised of a solution of a thickener, the pigment, and / or the coloring matter, and water in the following proportions: 1-30% by weight of the coloring matter and / or pigment; 1-15% by weight of the first thickener; 1-5% of a second additional thickener (instead of or in addition to the first thickener) for the rheological modification; and the rest, water. With particular reference to the coloring matter or pigment, the coloring matter for the purposes of this description is defined as any compound within the class either of basic dyes or dyes reactive with the fibers or direct, anionic, or a pigment that can impart a color to a cellulosic material such as a dry coloring material, usually an insoluble powder that is to be mixed with water, oil or other base to produce paint on similar products. More particularly, in one aspect of the present invention, there is thus provided a dye comprising, as a direct dye, a compound represented by the following formula (1).
wherein, ring A represents a benzene ring which may have a substituent or may also be cyclo-condensed with another aromatic ring; B represents an aryl group which may have a substituent or may be linked with R 2 to form a heterocyclic structure which will be described below, or a heterocyclic group which may have a substituent or may be linked with 2 to form a heterocyclic structure. which will be described later, D represents a nitrogen atom or a group CR4 (in which R4 represents a hydrogen atom or an alkyl group of Ci-S): E represents a group NR5, CR6R7 or CRS = CR7 (in which R5 represents an alkyl group of 02_5 which may have a substituent, an alkenyl group of C2-e which may have a substituent or an aryl group which may have a substituent, or form, when taken together with R2, a ring the which will be described later, and Rs and R7 each independently represent a hydrogen atom or an alkyl group of C -e), an oxygen atom or a sulfur atom; R1 represents an alkyl group of Ci_6 which may have a substituent, a C2-6 alkenyl group which may have a substituent or an aryl group which may have a substituent; R2 represents a divalent group attached to B or form, when taken together with R3 or R5, a ring which will be described later, R3 forms, when taken together with R2, a ring which will be described later; n means 0 or 1, with the proviso that when n = 0, R2 and R5, when taken together with N-C-C, form a heterocyclic structure containing nitrogen of 5 to 7 members which may have a substituent, or R2 is attached to B, whereby it forms a heterocyclic structure of 6 or 7 members which can have a substituent and can contain a heteroatom different from D and when n = 1, 2 and R3, when taken together with C = D-, form a heterocyclic structure containing nitrogen, from 5 to 7 elements, which can have a substituent, and X represents an anion. In formula (1), examples of the substituent that ring A may have include alkyl groups, aryl groups, alkoxy groups, amino groups, hydroxy groups, cyano groups, nitro groups and halogen atoms, more specifically, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a chlorine atom and bromine atoms. Examples of the aromatic ring with which ring A can be cyclo-condensed include a benzene ring. Examples of the aryl group represented by B include phenyl, 1-naphthyl and 2-naphthyl groups, while those of the heterocyclic group include the 2-benzothiazolyl and 3-indolyl groups, each of which can be substituted with a chlorine atom , a bromine atom, a nitro group, a cyano group, an alkyl group of ¾ -4, a phenyl group, a benzyl group, an alkoxy group of Ci_4i a hydroxy group, a phenoxy group, a benzyloxy group, an alkylsulfonyl group of Ci_4, a phenylsulfonyl group, a benzylsulfonyl group, an aminocarbonyl group, a mono- or di- (Ca_4) aminocarbonyl group, an aminosulfonyl group, an alkylcarbonyl group of C 1-4, an alkylcarbonylamino group of Ci_4, a group benzoylamino, a phenylazo group, and a group NR8R9 (in which R8 and R9 each independently represent a hydrogen atom, an alkyl group of Ci-, an aryl group, an aralkyl group, an amino group (Ci_4 alkyl) substituted or mono- or di- (alkyl) C1-) -substituted, an amino group (Ci_ alkyl) substituted by a group of the formula (1) from which a hydrogen atom has been removed, or a group (< ¾_4) (Ci_4 alkyl) amino). The number of these substituents is 1 to 3. The atom constituting the cycle can be linked with the substituent previously exemplified to form another cyclic structure. Examples of the alkyl group of ¾_6 represented by R4 in the case where D represents a group CR4 or by R6 or R7 in the case where E represents a group CRSR7 or CRS = CR7 include the methyl, ethyl, propyl, isopropyl and cyclohexyl. Preferred examples of R4, Rs or R7 include a hydrogen atom and methyl groups. Examples of the C 6 alkyl group represented by R 5 in the case where E represents a NR 5 group include the methyl, ethyl, propyl, isopropyl and cyclohexyl groups; those of the C2-S alkenyl group include the ethenyl and propenyl groups; and those of the aryl include the phenyl and naphthyl groups, each of which may be substituted with an aryl, alkoxy, amino, hydroxy or cyano group, or a halogen atom. Examples of the Ci_6 alkyl group represented by R1 include methyl, ethyl, propyl, isopropyl and cyclohexyl groups, those of the C2-6 alkenyl group include the ethenyl and propenyl groups, and those of the aryl group include the phenyl and naphthyl groups, of which the alkyl group is preferred as R1. Examples of the group that can be a substituent for them include the aryl groups, the cyano group, halogen atoms, a hydroxy group, the Ci_4 alkoxy groups, NR10R1: L (in which R10 and R11 each independently represent a hydrogen atom, an alkyl group of Ci_4, an aryl group, an aralkyl group, an unsubstituted amino group (" alkyl " -4 " or substituted mono- or di- (" alkyl), or a group (" Ci_4 alkoxy) (Cx.alkyl) amino) and a group of the formula (1) from which a hydrogen atom has been removed. Examples of R5-R2 or R2-R3 in the case where a heterocyclic nitrogen-containing structure of 5 to 7 members which may have a substituent which is formed by R2 and R5 when they are taken together with -C-C in n = 0, or by R2 and R3 when taken together with C = D-N in n = l, include the groups represented by - (CR ^ R13) m- (in which R12 and R13 each independently represent a alkyl group of CX-4 and m means an integer from 2 to 4). Examples of the divalent group, such as R2, attached to B in the case where a 6 or 7 membered heterocyclic structure which may have a substituent and may have a heteroatom different from D is formed by the binding of R2 to B when n = 0 include the groups -CH = - and -CO-0-. Examples of the anion represented by X "include chloride ions, bromide ions, iodide ions, trichlorozinic acid ions, ions of tetrachlorozinic acid, ions of sulfuric acid, ions of hydrosulfuric acid, ions of methyl sulfate, ions of phosphoric acid , formic acid ions and acetic acid ions.The thickener used in dye formation can be selected from synthetic and natural thickeners.More specifically, the composition of the thickening agents used in the dye formation can vary between a 0% for the synthetic thickener and 100% by weight for the natural thickener, and vice versa, depending on the response of the products used to the expense of the coloring matters used The mixtures that are more preferable with respect to the stability of the dispersion of the coloring matters contain between 1 to 30% by weight of the natural thickeners, and even more preferred between 1 to 15%, and 1 to 10% by weight of the synthetic thickeners, and even more preferably between 1 to 5%. The synthetic thickeners are preferably synthetic thickeners containing carboxyl and the natural thickeners are based on polysaccharides in the preferred embodiments of the invention. Examples of suitable synthetic carboxyl-containing thickeners which can be used according to the invention are aqueous solutions or gel-forming dispersions of polyethylenically or monoethylenically unsaturated monocarboxylic or dicarboxylic acids of low molecular weight, polymerized, such as polyacrylic acid and its homologs, for example the polymerization products of the acid-methacrylic or of the critical acid, and the polymers of the carboxyalkyl derivatives, such as idaconic or teraconic acid, similarly the aqueous solutions of, or the dispersions of, the maleic acid polymerized or its anhydride and fumaric acid and their homologs, such as, for example, citriconic acid or mesaconic acid, in addition to the olefin copolymers, for example, ethylene, propylene or butadiene or of lower alkyl acrylates, optionally substituted acrylamides, vinyl alcohols, vinyl ethers, vinyl esters, vinyl chloride, vinylidene chloride, styrene, acrylonitrile, and analogous alkyl compounds and the aforementioned monomers previously. These examples also include the reaction products of the described polymers and copolymers, with alcohols and polyhydric amines, or amino alcohols, and the combination of highly polymerized products with less highly polymerized products. The polysaccharides preferably used as the natural thickening agents according to the invention include degraded and / or optionally etherified natural products such as high molecular weight pea seed flour or guar flour and starch or cellulose ethers. In a particularly preferred embodiment, the thickener is formed only of thickeners of the material including carboxymethyl cellulose and starch. Although the dye components can be mixed to form the dye in a suitable manner, a particularly preferred method is. After the dye has been formed and applied to the selected surface of the cellulosic substrate, the substrate may be lightly dried to allow limited hardening of the dye on the substrate and to prevent discoloration of the dye from the substrate. In addition, the rate of application of the colorant may vary depending on the intensity of the desired shade of color on the surface of the substrate. For example, in a preferred embodiment the rate of application of the colorant is 1-40% by weight of the substrate and more preferably 1-15% by weight of the substrate. After application of the colorant to the substrate, in the second stage of the method, a film of a suitable coating material is applied as a coating to the colored cellulosic substrate to impart solidity with respect to rubbing in dry and wet conditions for the colorant which has reacted on the substrate. The methods of application for the coating material are similar to the printing or dyeing methods used for the application of the colorant and can include, but are not limited to, methods of applying the machine to a material other than paper, such as flexographic, bar seals, and / or pneumatic knife coaters. Furthermore, with respect to the coating material, the coating material is a natural or synthetic rubber formed of several compounds, including but not limited to polybutadiene, polyisobutylenes, polystyrenes, polyacrylates and polyurethanes. In a preferred embodiment, the material is a latex, which for the purposes of this invention is defined as any material within the class of polymers based on modified styrene butadiene or styrene-acrylate polymers modified with the provisions for changes in the value of TG of the polymer or the combination of polymers. More preferably, the coating may be a latex product with 50% solids which is used as a "varnish" layer on the substrate, to provide rubbing fastness in wet and dry conditions and to add gloss or a matte finish to the substrate. In addition, the rate of coating application to the substrate may vary depending on the level of solidity and the level of brightness required for the substrate, with the highest solidity properties and highest brightness achieved with a higher application rate of the coating. More specifically, in a preferred embodiment the rate of application for the coating will be within a range of 1% to 25% by weight of the substrate and more preferably between 1% and 5% by weight of the substrate. Colored carton produced as described, can be used in any corrugated application, for example corrugated containers or in displays at the point of purchase. The application of the coating material improves the printability of the material and ensures that the printing medium does not suffer the color shift in the underlying dyed substrate. Various alternatives are contemplated that are within the scope of the following claims, particularly pointing out and distinctly claiming the subject matter considered as the invention.