ES2713241T3 - Inhibitor material of color transfer - Google Patents

Abstract

The present invention relates to a color transfer inhibiting material consisting of a cellulose substrate functionalized with a quaternary ammonium compound, and characterized in that the cellulose substrate consists of cellulose particles or cellulose nanofibers obtained by electrospinning. Said material has a great capacity to inhibit the transfer of color, so it has utility to be used as an additive in washing clothes. It also relates to a process for preparing said material and to a laundry washing composition that incorporates it as a color protector.

Description

DESCRIPTION

Inhibitor material of color transfer

Field of the technique

[0001] The present invention relates to additives for washing clothes, in particular to a material that is suitable for inhibiting color transfer during washing.

State of the prior art

[0002] It is known that colored garments can lose a part of the coloring substances they contain during washing, which pass to the washing water and, from there, can be transferred to other garments present, of more pale or white colors , resulting in an undesired coloration of the latter.

[0003] This supposes an important inconvenience for the washing of the clothes as much to domestic level as to level of industrial washing.

[0004] A traditional method to avoid this color transfer between the washed clothes is simply to wash the clothes separately in the washing machine, depending on its color. However, making this separation is annoying, it involves a certain obstacle to optimizing the number of washes, and undesirable staining can not always be avoided in this way. This separation also means an increase in the washing time, and a greater consumption of water and electricity.

[0005] To respond to this problem, products have been developed as additives, typically in the form of wipes or in liquid form, which are added to the washing machine and easily absorb the possible colors detached during washing, and so on. It prevents that other garments present are tinted. Special detergents have also been developed for colored clothing.

[0006] In the literature, different technical solutions have been described that respond to this pattern. Ace! for example, in the US patent US4380453, the use of a substrate to which it is applied or impregnated with a dye-picking substance, for example a quaternary ammonium compound, of the glycidyl ammonium type, such as glycidyltrimethylammonium chloride, is described. or a trisubstituted 2-hydroxy-3-halopropyl ammonium derivative. The substrate as! treated serves to adsorb dyes that dissociate from the materials held, and so! the coloring of other materials present in the washing bath is avoided. Among the substrates, there is mentioned a cellulose textile material which may be in the form of woven, non-woven, rope, ball, knitted, or any other.

[0007] French patent application FR-A-2761702, also refers to the same problem of color transfer in the washing process. In it, the use of finely divided lignocellulosic substances is proposed to fix the dyes that are released from the fabrics during washing. Among these substances, the use of micronized and steam-treated wood powder and micronized straw are described. It is also described that said substances are not incorporated into the detergent formulation, but are added to the washing bath separately, for example, inside a bag of a mesh adjusted to the granulometry of the lignocellulosic substances, so that they do not allow the exit of the same to the bathroom, since it would be difficult to avoid the redeposition of the same on the clothes.

[0008] European patent application EP-A-1621604 also raises the problem of color transfer during washing and proposes a dye pick-up material comprising a substrate selected from a synthetic or natural woven or non-woven fabric, or paper , and an additive comprising one of the following polymers: proteins, chitin, chitosan, heterocyclic cationic polymers, polyvinylamine, polyethyleneamine, acrylic polymers, vinyl polymers, polyamine N-oxide, and mixtures thereof. The additive is fixed or incorporated into the substrate by means of impregnation or spraying.

[0009] In the international patent application WO-A-2009/071296, an alternative solution is proposed to prevent colorations and graying during the washing of textiles, which comprises using a cationized cellulosic substrate prepared from residues of textile materials of low quality, such as pieces of yarn and / or cut fibers. The substrate may also comprise cationized cellulose fibers. The substrate is preferably used in a container so that it does not come into contact with the clothes.

[0010] In the international patent application WO-A-02/12424, the use of a cationically modified polyester substrate with a polyepoxyamine to reduce the color transfer during washing is described.

[0011] The different solutions proposed in the state of the art have contributed to reduce the problem of the transfer of color in the washing of textiles, although they are not completely satisfactory, since in front of certain dyes and / or types of textiles, they can not completely avoid the accidental use of the garments.

[0012] Therefore, despite the solutions described in the state of the art, there remains a need to provide new materials that are more effective in preventing the transfer of color during the washing of textiles. Object of the invention

[0013] The object of the present invention is a material that inhibits the transfer of color.

[0014] A method for preparing said material also forms part of the object of the invention.

[0015] It also forms part of the object of the invention the use of said material to inhibit the transfer of color during the washing process.

[0016] A washing process comprising the use of said material also forms part of the object of the invention.

[0017] A composition comprising said material also forms part of the object of the invention.

Brief description of the drawings

[0018]

Figure 1

In Figure 1 the results of the test of Example 9 are plotted where the adsorption capacity of the Direct Red 83 dye was evaluated at different times, by different materials according to Examples 4 and 5 (invention) and Examples 3, 6 and 7 (comparative), in comparison with three commercial reference products (Reference Examples A, B and C). A solution of the dye was used at a concentration of 10 ppm, which was contacted with 10 mg of each material to be tested.

The ordinate shows the adsorption capacity expressed as mg of dye adsorbed by each gram of material tested, and the contact time between the material tested and the dye solution is plotted on the abscissa.

Figure 2

In Figure 2 the results of the test of Example 10 are plotted, where the maximum adsorption capacity of the Direct Red 83 dye was evaluated after a contact time of 60 minutes, by different materials according to Example 5 ( invention) and Examples 3 and 7 (comparative), in comparison with three commercial reference products (Reference Examples A, B and C). A solution of the dye was used at a concentration of 500 ppm, which was contacted with 10 mg of each material to be tested.

The ordinates represent the adsorption capacity expressed as mg of dye adsorbed by each gram of material tested, and on the abscissas each of the materials is represented.

Figure 3

Figure 3 graphically represents the results of a test carried out in Lini-test to measure the inhibition of color transfer during washing between a color donor tissue ( Direct Orange dye 39) and a white cotton tissue, using various products according to Examples 4 and 5 (invention) and Examples 3, 6 and 7 (comparative) in comparison with a detergent without anti-transfer additives and three commercial color transfer inhibitor products (Reference Examples A, B and C), according to the results obtained in Example 11.

In ordinates the anti-color transfer efficiency is represented, according to a numerical scale from 0 to 5, where 5 indicates the maximum efficiency. On the abscissa each of the tested materials is represented.

Figure 4

Figure 4 graphically represents the results of a test carried out in Lini-test to measure the inhibition of color transfer during washing between a color donor tissue ( Direct Red 83 dye ) and a white cotton tissue, using various products according to Examples 4 and 5 (invention) and Examples 3, 6 and 7 (comparative), as compared to a detergent without anti-transfer additives and three commercial products color transfer inhibitors (Reference Examples A , B and C), according to the results obtained in Example 11.

In ordinates the anti-color transfer efficiency is represented, according to a numerical scale from 0 to 5, where 5 indicates the maximum efficiency. On the abscissa each of the tested materials is represented.

Figure 5

Figure 5 graphically represents the results of a test carried out in Lini-test to measure the inhibition of the color transfer during washing between a color donor tissue ( Direct Black dye 22) and a white cotton tissue, using two products according to Example 4 (invention) and Example 3 (comparative), in comparison with a detergent without anti-transfer additives and two commercial products color transfer inhibitors (Reference Examples A and C), according to results obtained in Example 11.

In ordinates the anti-color transfer efficiency is represented, according to a numerical scale from 0 to 5, where 5 indicates the maximum efficiency. On the abscissa each of the tested materials is represented.

Figure 6

Figure 6 graphically represents the results of a test carried out in Lini.-test to measure the inhibition of color transfer during washing between a color donor tissue ( Acid blue dye 113) and a white polyamide fabric , using two products according to Example 4 (invention) and Example 3 (comparative), compared to a detergent without anti-transfer additives and two commercial color transfer inhibitor products (Reference Examples A and C), according to the results obtained in Example 11.

[0019] In ordinate the anti-color transfer efficiency is represented, according to a numerical scale from 0 to 5, where 5 indicates the maximum efficiency. On the abscissa each of the tested materials is represented.

Detailed description of the invention

[0020] The object of the present invention is a color transfer inhibiting material consisting of a cellulose substrate functionalized with a quaternary ammonium compound of formula (I):

where:

n is between 1 and 20;

R ¹ is selected from oxiranyl and 2-chloro-1-hydroxyethyl;

R ² and R ³ are independently selected from C ^1-6 alkyl and benzyl groups;

R ⁴ is selected from alkyl groups C ¹ - ^20; Y

X is selected from the group consisting of Cl, Br, I, tetrafluoroborate, trifluoromethanesulfonate and nitrate; and wherein the cellulose substrate consists of microcrystalline cellulose.

[0021] The authors of the present invention have developed a new material prepared from a substrate formed by microcrystalline cellulose, which, surprisingly, has superior properties as an inhibitor of color transfer with respect to the products described in the state of the art, in particular with respect to commercial products where the cellulose support is not nanostructured, but in the form of a common textile material, of the wipes type. The material developed is suitable as an additive to be used in washing clothes to prevent unwanted staining of garments.

The cellulose substrate

[0022] The color transfer inhibiting material, according to the present invention, is characterized in that it contains a cellulose substrate in the form of particles, which has specific physical-chemical characteristics, well differentiated from the textile cellulosic materials usually used as support. in color antitransfer products, and which give said material remarkably superior properties for the inhibition of color transfer.

[0023] The cellulose substrate used in the present invention is in the form of microcrystalline cellulose.

[0024] Generally, the cellulose particles are microparticles or nanoparticles of cellulose, that is they have an average size of the order of micrometers (or microns), usually between 1 pm and 1000 pm, or of the order of nanometers, usually between 1 nm and 1000 nm.

[0025] The distinction between microparticles and cellulose nanoparticles is not always well defined, since usually the particles are not granular, that is, they do not have an approximately spherical shape, but are fibrillar, defined typically as a function of their average thickness ( E) and its average length (L), so that, usually, the cellulose particles are classified as nanoparticles if at least one of said dimensions, in particular the thickness, is less than 1 μm. In the case of particles of fibrillar shape, they are also usually characterized by the parameter called "aspect ratio", which is the relationship between the length and thickness of said fibers.

[0026] The cellulose particles have an average size between 0.01 and 400 μm, more preferably between 0.05 μm and 200 μm. Said medium size of the cellulose particles, whose shape is irregular, as indicated above, usually refers to its equivalent average diameter, that is, the diameter of a sphere of volume equivalent to that of the particle. In the context of the present invention, the term "average size" is used interchangeably to refer to the average diameter, or equivalent average diameter.

[0027] The average size of the cellulose particles, defined according to their equivalent average diameter, can be determined according to the usual analytical procedures for measuring the average size of particles, which are well known to the person skilled in the art, for example, by methods of screening, by the method of the area sensitive to electric current (Coulter counter), by dispersion of laser light, or by the use of electron microscopy, in particular the scanning electron microscope (SEM, scanning electron microscope), or the transmission electron microscope (TEM, transmission electron microscope). In the chapter Analisis of the size of the particles, of the book ME Aulton, Pharmacy. The science of the design of pharmaceutical forms, second edition, Elsevier, Madrid, 2004, Chapter 10, pp154-167 describes the most common parameters and methods to define and measure the size of particles.

[0028] According to the invention, the cellulose particles that act as the substrate of the color transfer inhibiting material are microcrystalline cellulose.

[0029] In the invention, the cellulose particles used as support are microcrystalline cellulose.

[0030] Microcrystalline cellulose is a crystalline powdery substance, obtained by controlled hydrolysis of acelulose, whose characteristics are well known and described, for example, in the manual of pharmaceutical excipients, RC Rowe, PJ Sheskey and PJ Weller, Handbook of Pharmaceutical Excipients, fourth edition, Pharmaceutical Press, 2003.

[0031] The microcrystalline cellulose has an average particle size that varies usually between 20 pm and 300 pm, depending on the different suppliers and obtaining methods. Preferably, a microcrystalline cellulose with a mean particle size of between 40 pm and 150 pm, more preferably between 50 pm and 120 pm, and even more preferably between 70 pm and 100 pm is used.

[0032] The microcrystalline cellulose particles are granular, with an approximately spherical shape, with an "aspect ratio" usually comprised between approximately 1 and 3.

[0033] Microcrystalline cellulose can be obtained commercially from various suppliers, for example through the company FMC Biopolymer, under the general trade name AVICEL®; or through the company Acros Organics that distributes microcrystalline cellulose with an average particle size of 50 pm or 90 pm; also the company Sigma-Aldrich distributes microcrystalline cellulose under the denomination Cellulose microcrystalline 310697, with an average particle size of 20 pm; and also the company JRS (J. Rettenmaier & Sohne) commercializes microcrystalline cellulose under the names VIVAPUR® or HEWETEN®, in different particle sizes, for example the so-called HEWETEN® 102, with an average particle size of 90 μm.

[0034] As a comparative example, the cellulose particles used as support are pulverulent cellulose.

[0035] Powdered cellulose is a powder obtained by reducing the size of the α-cellulose by mechanical means, the characteristics of which are specified, for example, in the RC Rowe book, cited above, and which has a particle size usually comprised between 20 pm and 250 pm. The cellulose in powder form can be obtained commercially, for example through the company J. Rettenmaier & Sohne, under the general trade name ARBOCEL®, according to the ARBOCEL® M80 or ARBOCEL® A300 varieties, for example.

[0036] As a comparative example, the cellulose particles used as support are microfibrillated cellulose.

[0037] Microfibrillated cellulose (MFC, microfibrillated cellulose) has dimensions that usually vary between 0.01 pm and 4 pm of average thickness, preferably between 0.01 pm and 0.1 pm, and between 1 pm and 100 pm of average length. Usually, they have an "aspectratio" of up to 100, at most. Alternatively, microfibrillated cellulose it can be characterized by the mean diameter, or equivalent average diameter of the particles, which is usually between 0.05 and 15 pm.

[0038] Microfibrillated cellulose is obtained from cellulose, or from microcrystalline cellulose, by a mechanical treatment of high pressure homogenization, optionally accompanied by a chemical or enzymatic treatment. Microfibrillated cellulose is usually less than 1 μm thick, so it is usually called nanocellulose, or cellulose nanoparticles.

[0039] Microfibrillated cellulose is well known to the person skilled in the art, and can be obtained commercially, in different sizes, from various suppliers, in particular from the company J. Rettenmaier & Sohne, for example, the one known with the trade name ARBOCEL® UFC 100, whose fibers have a length of approximately 8 pm.

[0040] As a comparative example, the cellulose particles used as support are nanocrystalline cellulose.

[0041] Nanocrystalline cellulose is a highly crystalline form of cellulose, which is in the form of needles and is obtained by hydrolysis of cellulose with a strong acid under controlled conditions, for example, as described in the Habibi et al. to the. Cellulose nanocrystals: chemistry, self-assembly, and applications, Chem. Rev., 2010, 110, p3479-3500. The nanocrystalline cellulose has dimensions usually between 3 nm and 5 nm in thickness and up to 200 nm in length.

[0042] In the Aspler et al. Review of nanocellulosic products and their applications, from the book: Biopolymer nanocomposites. Processing, properties and applications, Edited by A. Dufresne, S Thomas and LA Pothan, 2013, John Wiley & Sons (ISBN 978-1-118-21835-8), chapter 20, pp461-508, describe the properties of microparticles and cellulose nanoparticles mentioned above.

[0043] As a comparative example, the cellulose particles used as support are prepared by grinding cellulose nanofibers obtained by electrospinning. The particles as! obtained, in the form of fibers or filaments, generally have a mean diameter between 0.1 pm and 1 pm, more preferably between 0.3 pm and 0.8 pm, and an average length usually between 2 pm and 100 pm , more preferably comprised between 3 pm and 80 pm, and even more preferably comprised between 4 pm and 50 pm.

[0044] The technique known as electrospinning is well known to the person skilled in the art, and allows the preparation of nanofibers from a solution of a certain material, usually polymers, through the application of electric current with a sufficiently high voltage, so that causes the expulsion of fine threads from a capillary, while evaporating the solvent, thus forming the nanofibers of said material. For preparing cellulose nanofibers, for example, a solution of cellulose acetate in a solvent or a mixture of solvents can be used, for example, a mixture of acetone / dimethylacetamide. Cellulose acetate can be obtained commercially. For example, the company Sigma-Aldrich distributes cellulose acetate with an average molecular weight (Mn) of 30,000.

[0045] Suitable conditions for performing the electrospinning of cellulose acetate are, for example, a voltage of 30 kV, a flow of between 3 and 4 mL / h, a distance to the collector of 12 cm, and a speed of rotation of 500 rpm.

[0046] Next, the obtained cellulose acetate nanofibers are hydrolyzed, usually with a sodium hydroxide solution to deacetylate the product and obtain cellulose nanofibers. The solid obtained is filtered and dried, preferably at a temperature between 40 ° C and 80 ° C, more preferably between 55 ° C and 65 ° C for a period usually comprised between 0.5 and 3 hours, preferably for approximately one hour.

[0047] The nanofibers obtained according to this electrospinning process are crushed, for example with an IKA A 11 basic mill, to obtain cellulose particles. The grinding step can be carried out on the cellulose acetate nanofibers obtained directly from the electrospinning process and / or after the hydrolysis step, once the cellulose is deacetylated.

[0048] As a comparative example, the cellulose support used in the color transfer inhibiting material are cellulose nanofibers, prepared by electrospinning, without crushing.

Quaternary ammonium compound

[0049] The color transfer inhibiting material consists of a microcrystalline cellulose support, functionalized with a quaternary ammonium compound, which is characterized by having a high affinity for dyes or dyes.

[0050] In particular, the quaternary ammonium compound used in the material object of the present invention is a product of formula (I):

where:

n is between 1 and 20;

Ri is selected from oxiranyl and 2-chloro-1-hydroxyethyl;

R ² and R ³ are independently selected from C ^1-6 alkyl and benzyl groups;

R ⁴ is selected from alkyl groups C ¹ - ^20; Y

X is selected from the group consisting of Cl, Br, I, tetrafluoroborate, trifluoromethanesulfonate and nitrate.

Definitions

[0051] In the context of the present invention, a C ^1-6 alkyl group refers to a saturated hydrocarbon group having between 1 and 6 carbon atoms, which may be linear or branched, and includes, among others, the groups methyl, ethyl, n-propyl, isopropyl, sec-butyl, ferf-butyl, n-pentyl, 1-methyl butyl or n-hexyl.

[0052] Analogously, a C ^1-20 alkyl group refers to a saturated hydrocarbon group having between 1 and 20 carbon atoms, which may be linear or branched, and includes, among others, the methyl, ethyl, n-groups. propyl, isopropyl, sec-butyl, fert-butyl, n-pentyl, 1-methyl butyl, n-hexyl, n-octyl, n-decyl, n-dodecyl n-tetradecyl, n-hexadecyl or n-octadecyl.

[0053] A n-C ⁸ -C ¹⁸ alkyl group refers to a saturated linear hydrocarbon group having between 8 and 18 carbon atoms, and is formed by the n-octyl, n-nonyl, n-decyl, n groups -undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl and n-octadecyl.

[0054] The oxiranyl group refers to the radical:

[0055] The 2-chloro-1-hydroxyethyl group refers

[0056] For its part, the tetrafluoroborate anion refers to the group BF4 ', the trifluoromethosulfonate (or triflate) is the anion SO ³ (CF ³ ) -, and the nitrate group corresponds to the anion NO 3'.

[0057] In a preferred embodiment of the invention, the compound of formula (I) is characterized in that n is 1, R ² , R ³ and R ⁴ are selected from the group consisting of methyl, ethyl, n-propyl and isopropyl, and X is selected from the group consisting of Cl, Br, and I. In a still more preferred embodiment, R ² , R ³ and R ⁴ are methyl and X is Cl.

[0058] In a preferred embodiment of the invention R ¹ is oxiranyl.

[0059] According to various particular embodiments of the invention, the quaternary ammonium compound of formula (I) is characterized in that:

- n is between 1 and 20, preferably between 1 and 10, more preferably between 1 and 5, and even more preferably n is 1;

- R ¹ is selected from: oxiranyl and 2-chloro-1-hydroxyethyl; more preferably R ¹ is oxiranyl;

- R ² and R ³ are independently selected from alkyl C ^1-6, most preferably they are independently selected from the group consisting of methyl, ethyl, n-propyl and isopropyl; and even more preferably R ² and R ³ are both methyl;

- R ⁴ is a C ¹ alkyl group - ^20, more preferably is selected from methyl, ethyl, n-propyl, isopropyl, or C ⁸ -C ¹⁸ Nalkyl, even more preferably R ⁴ is methyl;

- X is selected from the group consisting of Cl, Br, I, tetrafluoroborate, trifluoromethanesulfonate and nitrate, preferably X is selected from Cl, Br and I, and even more preferably X is Cl.

[0060] In a particularly preferred embodiment of the invention, the compound of formula (I) is characterized in that n is 1, Ri is oxiranyl; R2, R3 and R4 are methyl and X is chosen from Cl, Br, I, more preferably X is Cl. According to this embodiment, the product of formula (I) is glycidyltrimethylammonium chloride (CAS number 3033-77-0), which is commercially available from various suppliers, for example, Sigma-Aldrich (Switzerland), or from SKW Quab Chemicals (Quab® 151 product).

[0061] In another particularly preferred embodiment of the invention, the compound of formula (I) is characterized in that n is 1, R1 is 2-chloro-1-hydroxyethyl, R2, R3 and R4 are methyl and X is chosen from Cl, Br, I; more preferably X is Cl. According to this embodiment, the product of formula (I) is (3-chloro-2-hydroxypropyl) trimethylammonium chloride (CAS number 3327-22-8), which can be obtained through the company Sigma -Aldrich, or through the company SKW Quab Chemicals (product Quab® 188).

[0062] In another preferred embodiment of the invention, the compound of formula (I) is characterized in that n is 1, R 1 is 2-chloro-1-hydroxyethyl; R2 and R3 are methyl, R4 is selected from a C8-C18 n-alkyl, more preferably chosen from the group consisting of noctil, n-dodecyl, n-hexadecyl, and n-octadecyl; and X is selected from Cl, Br, I, more preferably X is Cl. According to this embodiment, usually the compound of formula (I) is a mixture of at least two compounds, with different R4, in different proportions. Some of these products are available commercially, through the company SKW Quab Chemicals, for example the commercial product Quab® 342 where R4 is n-dodecyl, the commercial product Quab® 360, a mixture of R ⁴ = n-octyl and R ⁴ = n-octadecyl; or the commercial product Quab® 426, a mixture of R ⁴ = n-dodecyl, R ⁴ = n-hexadecyl and R ⁴ = n-octadecyl; in all of them R1 is 2-chloro-1-hydroxyethyl, R2 and R3 are methyl, and X is Cl.

Preparation procedure

[0063] In the material of the invention, the cellulose support is functionalized with the quaternary ammonium product of formula (I). This means that said product is bound to the cellulose by reaction with the hydroxyl groups present therein, to form cellulose particles or functionalized cellulose nanofibers, according to the following structure, where the circle represents the cellulose support:

[0064] A method for preparing the material of the invention also forms part of the object of the invention. To prepare said material, ie to functionalize the microcrystalline cellulose particles, for example, a process comprising the following steps can be used:

a) preparing an aqueous suspension of the cellulose substrate together with the quaternary ammonium compound of formula (I) at alkaline pH comprised between 12 and 14, and keeping the assembly under agitation;

b) filtering and subjecting the resulting soaked cellulosic material at a temperature between 60 ° C and 110 ° C;

c) wash the resulting material with water until neutral pH and dry at a temperature between 60 ° C and 80 ° C.

[0065] To obtain the aqueous suspension at alkaline pH, any alkalizing agent such as, for example, alkali hydroxides or alkali carbonates can be used. Preferably, sodium hydroxide is used as the alkalizing agent.

[0066] In the initially prepared suspension, in step a), the concentration of sodium hydroxide is preferably comprised between 2% and 10%, more preferably comprised between 3% and 5%. and even more preferably comprised between 4% and 4.5%; the concentration of the quaternary ammonium compound of formula (I) is preferably comprised between 2% and 15%, more preferably between 5% and 10%, and even more preferably comprised between 8% and 9%; and the concentration of cellulose is preferably comprised between 1% and 10%, more preferably comprised between 3% and 5%, and even more preferably comprised between 4% and 4.5%; where all percentages are expressed by weight.

[0067] Ace! thus, the molar ratio between the cellulosic material / sodium hydroxide / compound of formula (I) is preferably comprised between the following values: 1 / (3-10) / (1.5-5), more preferably comprised between 1 / ( 4.0-4.5) / (2.0-2.5) and even more preferably said molar ratio is 1 / 4.1 / 2.1.

[0068] In step a) the assembly is kept under agitation at room temperature, for example between 10 minutes and 3 hours, preferably between 15 minutes and 1.5 hours, by mechanical agitation at, for example, between 600 and 1500 rpm , or under magnetic stirring.

[0069] Next, according to step b) of the process, most of the solution is removed by filtration and the soaked cellulosic material is introduced into an oven, at a temperature comprised between 60 ° C and 110 ° C, preferably at 100 ° C, during a period preferably comprised between 15 minutes and 24 hours.

[0070] In step c), the functionalized cellulose obtained is repeatedly washed with water until the water of the washings has an approximately neutral pH. The resulting material is dried at a temperature between 60 ° C and 80 ° C, for a period of time preferably comprised between 12 and 24 hours.

[0071] In step a) two alternative procedures can be followed. According to a first alternative, initially an aqueous solution of the alkalizing agent, preferably sodium hydroxide, is prepared with the quaternary ammonium compound of formula (I) and on said solution the cellulose particles are added and the whole is then agitated for a period of time. preferably comprised between 10 minutes and 3 hours, more preferably comprised between 15 minutes and 1.5 hours.

[0072] Alternatively, a mixture can first be prepared by adding the cellulosic material to an aqueous solution of the alkalizing agent, preferably of sodium hydroxide, stirring for a period preferably comprised between 5 minutes and 1.5 hours, and then the compound of quaternary ammonium of formula (I), stirring again, preferably for between 5 minutes and 1.5 hours.

[0073] According to this procedure it was possible to functionalize the cellulose particles and the cellulose nanofibers. The effectiveness of the functionalization was assessed by performing an elementary analysis of the materials prepared and calculating the percentage of N incorporated, that is, the grams of N per 100 g of functionalized cellulose. Values ranging from 0.3 to 0.9 were obtained (see Examples 3 to 8) for cellulose particles or cellulose nanofibers. The same basic analysis test carried out with commercial wipes allowed to verify that said products had comparable functionalization values, between 0.4-0.6 (see Examples 3 to 8).

Use of the material of the invention

[0074] Various application tests were carried out to compare the anti-color transfer material according to the present invention, and other commercial products based on textile cellulosic materials, of the wipes type.

[0075] As in Examples 9 and 10, the capacity of the material of the invention was evaluated, compared with three commercial products of the type anti-color transfer wipes, to adsorb the dyes, observing that the product of the invention has greater capacity of absorption, and also allows discoloration more quickly than commercial products compared.

[0076] The results of the tests described in Examples 9 and 10 are graphically represented in Figure 1, where the dye adsorption capacity is compared as a function of time, and in Figure 2, where the maximum capacity is compared. Adsorption of dye at 60 minutes.

[0077] On the other hand, in Example 11 the effectiveness of the material of the invention was evaluated to avoid the transfer of color between tissues, according to a test carried out in a Lini-test equipment that simulated washing conditions in a washing machine, and wherein colored fabrics and white fabrics were introduced, together with a detergent without anti-color transfer additives and the material of the invention, or three commercial products, in addition to said detergent as a reference. Colored fabrics were tested with various colorants, and white cotton and polyamide fabrics.

[0078] It was observed that the products according to the present invention were surprisingly more effective than the reference products in preventing the transfer of color to white tissues, especially under the conditions of greatest danger of color transfer, ie between direct dyes and cotton fabrics, and between acid and polyamide dyes. The results of the test for these especially relevant cases have been represented graphically in Figures 3, 4, 5 and 6, where it can be seen that the material according to the present invention (dark bars) was more effective in preventing color transfer than the reference products (clear bars), obtaining values close to total inhibition (5).

[0079] Therefore, it is part of the object of the present invention to use the material of the invention to inhibit the transfer of color during the laundry washing process.

[0080] As such , the material of the invention is suitable to be added as an additive during laundry, typically in automatic washing using any type of commercially available washing machine. Said material can be added, for example, at the start of the main washing program, together with the detergent, or immediately before or after adding the detergent.

[0081] The material of the invention is added to the washing machine in an amount usually comprised between 1 g and 50 g per each kg of clothing, although said quantity can be conveniently adjusted depending on the needs.

[0082] A method for washing textiles comprising the use of said material also forms part of the object of the invention.

[0083] Said method consists of following the usual washing process for each washing machine, according to any of the available programs, at any temperature, and of any duration, and is characterized by the fact of adding the color transfer inhibiting material of The present invention during washing, preferably is added together with the detergent, or alternatively immediately before or after adding the detergent, to act during the main washing step, which is when there is a greater risk of color transfer.

[0084] The product of the invention, in the form of fine functionalized cellulose particles, acts in the washing bath, adsorbing the colorant that can be detached from the colored garments, and is simply removed during rinsing, without leaving any residue and without damaging the clothes. Therefore, the elimination of the anti-transfer product at the end of the washing is not required, as is the case with other commercial products, such as wipes.

[0085] The material of the invention can be incorporated into any composition suitable for use in washing clothes, for example, a washing additive or a detergent composition.

[0086] For example, the material of the invention can be added to a detergent composition, so that a detergent is obtained which already has a color transfer inhibiting product incorporated.

[0087] Detergent compositions suitable for incorporating the color transfer inhibitor product according to the present invention can be, without limitation, any type of detergent composition suitable for washing textile garments, and which are well known to the person skilled in the art. matter, for example, as described, in the book JJ Garcia Dominguez, Tensioactivos y Detergencia, Editorial Dossat, Madrid, 1986 (ISBN 84-237-0687-7); or in the book G. Jakobi and A. Lohr, Detergents and Textile Washing. Principles and Practice. VCH Verlagsgesellschaft, Weinheim, 1987 (ISBN 3-527-26811-1).

[0088] Thus, a composition for washing clothes comprising the color transfer inhibiting material of the present invention also forms part of the object of the invention.

Examples

Preparative Example 1: Preparation of cellulose nanofibers by electrospinning (Comparative)

[0089] A solution at 22% by weight of cellulose acetate (Sigma Aldrich 180955, average molecular weight Mn, 30,000) was prepared in a mixture of the solvents acetone and dimethylacetamide in a 1: 1 ratio by weight.

[0090] The resulting solution was subjected to an electrospinning process in the commercial equipment, model NF-103 of the company MECC Co. Ltd. The conditions used in said process were the following: voltage = 30 kV, flow = 3-4 mL / h, distance to the collector = 12 cm, collector rotation speed = 500 rpm. Some nanofibers of cellulose acetate were obtained, forming a mesh.

[0091] Thereafter, said nanofibers were deacetylated, for which they were submerged in 3.5 L of a 0.3 M NaOH solution for 1 hour, and the deacetylation was controlled by infrared spectroscopy (IR / ATR, Infraed / Attenuated Total Reflection), for which a commercial equipment was used, model IRAffinity-1 with accessory Miracle ™ ATR of the company SHIMADZU.

[0092] Next, the nanofibers were filtered, washed with water, and dried at a temperature of 60 ° C, overnight.

[0093] The cellulose nanofibers thus obtained were characterized using an electronic scanning microscope (SEM, Scanning Electron Microscopy), specifically using a JSM-6010-LV model equipment from JEOL. The diameter of said fibers was 452 nm ± 130 nm.

Preparative Example 2: Preparation of cellulose particles by grinding cellulose nanofibers obtained by electrospinning (Comparative)

[0094] Starting from the cellulose nanofibers prepared in the preparation Example 1, which were crushed using an IKA A 11 basic mill for 15 minutes to obtain a fine powder.

[0095] The size of said particles obtained using the scanning electron microscope is characterized, observing that the particles prepared from the nanofibers had a length between approximately 4 and 20 | jm.

Examples 3 to 8: Functionalized cellulose particles

[0096] The following cellulose particles were functionalized: microcrystalline cellulose (invention) (ACROS ORGANICS, Product 38231, particle size 90 jm), microfibrillated cellulose (comparative) (Arbocel, Product UFC 100, average size of the particles between 6- 12 jm (d50)), and the particles prepared in Preparative Example 2 (comparative).

[0097] These substrates were functionalized with glycidyltrimethylammonium chloride (Allorachem, product 43831949).

[0098] 12 g of the particles obtained in Preparative Example 2, and 100 g of microcrystalline cellulose and microfibrillated cellulose were used as starting material.

[0099] To prepare the anti-color transfer material from said cellulose particles, two alternative procedures, described below, were followed, which are totally analogous, and differ only in the order in which the reagents are added. In the case of the cellulose particles of Preparative Example 2 only the first one was followed (procedure 1), while the microcrystalline cellulose and the microfibrillated cellulose were functionalized by the two methods.

[0100] Procedure 1: An aqueous solution with NaOH and glycidyltrimethylammonium chloride was prepared in a vessel, and to said solution the cellulose particles were added, so that the proportion by weight of the cellulose particles was in all cases 4.2%, the proportion by weight of NaOH was 4.3% and the concentration of glycidyltrimethylammonium chloride was 8.3%, which represented a cellulose molar ratio / NaOH / glycidyltrimethylammonium chloride of 1 / 4,1 / 2.1. The whole was stirred for 1 hour at room temperature by mechanical agitation at 1000 rpm.

[0101] Next, the cellulose particles were filtered, to remove most of the dissolution, leaving the cellulose material soaked, and then said material was placed in an oven at 100 ° C for 30 minutes. Subsequently, the final product was washed with water several times until the water in the washings had a neutral pH. The resulting material was dried at 80 ° C for 20 hours.

[0102] Method 2: An aqueous solution of NaOH was prepared in a vessel, the cellulose particles were added, and the whole was stirred for 30 minutes at room temperature by mechanical stirring at 1000 rpm. The glycidyltrimethylammonium chloride was then added, and mechanically stirred at 1000 rpm for a further 15 minutes at room temperature. As in the previous process, the proportion by weight of the cellulose particles in all cases was 4.2%, the proportion by weight of NaOH was 4.3% and the concentration of glycidyltrimethylammonium chloride was 8%. , 3%, which represented a cellulose / NaOH / glycidyltrimethylammonium chloride ratio of 1 / 4.1 / 2.1.

[0103] The cellulose particles were then filtered to remove most of the dissolution, and from this point on, the same as in procedure 1, after filtration continued.

[0104] According to said procedures, cellulose particles functionalized with the quaternary ammonium compound glycidyltrimethylammonium chloride were obtained. To verify the degree of functionalization, an elementary analysis of said products was carried out, and the% of N they contained was calculated, that is, the grams of N per 100 grams of sample analyzed. The results are shown in Table 1.

TABLE 1

[0105] The degree of functionalization was also compared with that of three commercial products (Reference examples A, B and C), all of them in the form of wipes, also analyzing in this case the% N contained in said products. It was found that the percentage of functionalization, for the case of reference examples A and B, were comparable to those of the products of the invention. Reference Example C, had a large dispersion of the results (between 0.194 and 2.802), obtained in 6 repetitions of the test for different samples of the same product, so I do not calculate the average value since the distribution of the ammonium compound Quaternary was not homogeneous in the sample.

Example 9: Test of the dye adsorption capacity by the material of the invention: kinetic study

[0106] An assay was carried out to evaluate the adsorption capacity of the Direct Red 83 dye (CAS 15418-16-3) by the material object of the present invention, comparatively with respect to commercial products, as a function of the contact time (or kinetic study).

[0107] For this the amount of dye adsorbed by the material, expressed as mg of dye per each gram of material, was determined at different times (1, 5, 10, 15, 30, 45 and 60 minutes).

[0108] 10 mg of the material to be tested was contacted in 10 mL of a 10 ppm solution of Direct Red 83 dye. To determine the amount of dye adsorbed on the material at the different times, the absorbance of the solution was measured by UV-visible spectroscopy, and said values were interpolated in a line of calibration of the dye.

[0109] The results obtained are shown in Table 2, and are represented in graphical form in Figure 1. It can be seen that all the materials tested according to the present invention showed a higher adsorption capacity compared to commercial products, and also They showed a higher speed of performance.

[0110] The theoretical maximum adsorption capacity for the tested Direct dye 83.1 solution is 10 mg of dye / g material. When the observed adsorption capacity was equal to the theoretical one, the complete discoloration of the solution was observed.

TABLE 2

[0111] All the materials according to the present invention were able to adsorb all the dye, producing the total decoloration of the solution. The complete adsorption occurred after 1, 25, 10, 15 and 5 minutes for Examples 3, 4, 5, 6 and 7, respectively. In contrast, none of the Reference Examples reached this theoretical maximum value, but showed lower maximum adsorption values.

Example 10: Testing the dye adsorption capacity by the material of the invention: 60 minute study

[0112] In this test the adsorption capacity of Direct Red dye 83 (CAS 15418-16-3) by the material object of the present invention was evaluated, comparatively with respect to commercial products, setting a contact time of 60 minutes.

[0113] An analogous procedure to that described in Example 9 was followed, with 10 mg of the material to be tested being contacted with 10 mL of a Direct Red 83 dye solution having a concentration of 500 ppm.

[0114] The materials tested were those corresponding to Example 3 (comparative) (support of cellulose nanofibers prepared by electrospinning and crushed), Example 5 (invention) (microcrystalline cellulose support) and Example 7 (comparative) (microfibrated cellulose support ), comparatively with respect to three commercial products in the form of wipes (Reference Examples A, B and C).

[0115] The results obtained are shown in Table 3, and are plotted in Figure 2.

TABLE 3

[0116] It can be seen that all the materials according to the invention showed a dye adsorption capacity superior to that of the reference materials.

Example 11: Testing the effectiveness of the materials of the invention as anti-color transfer agents

[0117] An assay was conducted to evaluate the effectiveness as anti-color transfer agents of the materials according to the present invention in the laundry of garments. Specifically, in this trial the ability of several products to avoid the transfer of a donor tissue towards an acceptor tissue was evaluated. This test is recommended by the AISE ( International Association for Soaps, Detergents and Maintenance Products) and the one defined by the EU in Ecolabel for detergents for colored clothing.

[0118] The color acceptor tissues used in the assay were:

- 100% cotton with green lines according to ISO 2267. Dimensions of each test tube: (5.5 x 16) cm

- Polyamide according to ISO 105 F03. Dimensions of each test tube: (6 x 16) cm.

[0119] The acceptor tissues were pre-washed 3 times at 60 ° C in a cotton program with a detergent without optical brighteners.

[0120] The color donor tissues used in the assay were: Direct Orange 39 (CAS 1325-54-8), Direct Red 83 (CAS 15418-16-3), Direct Black 22 (CAS 6473-13-8) and Acid Blue 113 (CAS 3351-05-1), all of them available commercially, for example, through EMPA or WFK. 0.3 g of each donor tissue was used for the assays.

[0121] For the realization of the test a Lini-Test Atlas equipment was used. Said equipment consists of a water bath in which a device with 8 hermetically sealed containers rotates at a speed of (40 ± 2) rpm. In each container, a donor tissue and an acceptor of each type were included along with 100 mL of a solution of the product to be tested.

[0122] When the water bath reached the temperature of 30 ° C (± 0.5 ° C) the prepared containers were introduced. At this time the bath continued heating at a speed of 2 ° C / min until reaching 60 ° C and remained constant for 20 minutes. After the assay time, the acceptor tissues were removed and rinsed under running water. The tissues were allowed to air dry avoiding direct light.

[0123] The tissues were evaluated spectrophotometrically at the beginning and at the end of the test in order to be able to calculate the amount of color accepted (had) for each specimen.

[0124] For the evaluation, a Datacolor Spectraflash SF 600 PLUS-CT spectrophotometer was used under the following reading conditions:

- Measurement geometry: d / 8 °

- Observed D65 / 10 °

- 420 nm of cut off

[0125] The cotton and polyamide fabrics were evaluated independently, since their behavior is totally different, as well as each of the dyes.

[0126] The materials prepared in Examples 4 and 5 (invention) and Examples 3, 6 and 7 (comparative) were tested, all at a dose of 0.5 g, comparatively with respect to three types of anti-transfer wipes. color (Reference Examples A, B and C), dosed according to the manufacturer's recommendations according to a certain surface and not by weight.

[0127] The products of Examples 3-7 and of the Reference Examples AC were tested together with a simple commercial detergent, without anti-color transfer additives, which were also tested by themselves, as a reference ( Det Product ).

[0128] The evaluation of the anti-transfer efficiency was based on a numerical assessment assigned based on a gray scale following the UNE EN ISO 105-A04 standard. Values range from 0 (black) to 5 (white). At higher value, better inhibition of color transfer.

[0129] Table 4 summarizes the results obtained in the test for the materials according to Examples 4 and 5 (invention) and Examples 3, 6 and 7 (comparative), compared to commercial products (Examples of Reference A, BC), and regarding the commercial detergent without any anti-color transfer additive (Det). The color transfer for each donor tissue is tested independently for each type of acceptor tissue (cotton and polyamide).

TABLE 4

[0130] It is observed that for the three direct dyes tested (Direct Orange, Direct Red and Direct Black), the anti-color transfer results with the products of the invention are markedly superior to the comparative commercial products in the tests carried out with cotton as acceptor tissue. In the case of polyamide, the inhibition of color transfer is easier for all products, since direct dyes have more affinity for cotton than for polyamide, so the results obtained do not allow to discriminate the effectiveness of the different products analyzed.

[0131] It is also observed that for the acid dye tested (Acid blue), the anti-color transfer results obtained with the material of the invention in polyamide are clearly superior to those obtained with commercial reference products. Acid dyes have a greater affinity for polyamide, so in the cotton test the results of inhibition of color transfer were good for all products, and did not allow to discriminate the effectiveness between them.

[0132] Figures 3, 4, 5 and 6 graphically represent the results of Table 4 for the three direct dyes in cotton, and for the acid dye in polyamide. In all of them, the superiority of the material of the invention can be observed in comparison with the rest of the products evaluated.

Claims (9)

1.- Color transfer inhibiting material consisting of a cellulose substrate functionalized with a quaternary ammonium compound of formula (I):

where: n is between 1 and 20; Ri is selected from oxiranyl and 2-chloro-1-hydroxyethyl; R2 and R3 are independently selected from C1-6 alkyl and benzyl groups; R4 is selected from C1-20 alkyl groups; Y X is selected from the group consisting of Cl, Br, I, tetrafluoroborate, trifluoromethanesulfonate and nitrate; and wherein the cellulose substrate consists of microcrystalline cellulose. 2. Material according to claim 5, characterized in that the microcrystalline cellulose has an average particle size comprised between 40 pm and 150 pm. 3. Material according to any of claims 1 or 2, characterized in that in the compound of formula (I) n is 1; R2, R3 and R4 are selected from the group consisting of methyl, ethyl, n-propyl and isopropyl, and X is selected from the group consisting of Cl, Br, and I. 4. Material according to claim 3, characterized in that R2, R3 and R4 are methyl and X is Cl. 5. Material according to claim 4 characterized in that the product of formula (I) is glycidyltrimethylammonium chloride. 6. Process for preparing the color transfer inhibiting material according to any of claims 1 to 5, comprising the following steps: a) preparing an aqueous suspension of the cellulose substrate together with the quaternary ammonium compound of formula (I) at alkaline pH comprised between 12 and 14 and maintaining the assembly under agitation; b) filtering and subjecting the resulting soaked cellulosic material at a temperature between 60 ° C and 110 ° C; c) wash the resulting material with water until neutral pH and dry at a temperature between 60 ° C and 80 ° C. 7. Use of the material according to any of claims 1 to 5 to inhibit the transfer of color during the laundry washing process. 8. Process for washing textiles comprising the use of the material according to any one of claims 1 to 5. 9. Composition for washing clothes comprising the material according to any one of claims 1 to 5.