LU93386B1 - Process for processing materials containing fibers - Google Patents

Abstract

Shown and described is a process for processing a material containing fibers, comprising the steps of (a) providing a mixture comprising (i) at least one polymer and (ii) a polar aprotic solvent, (b) contacting the material to be processed with the material (c) mixture obtained in (a) to obtain a mixture of the material and the mixture provided in (a); (c) treating the mixture obtained in step (b) so that at least a portion of the polymer adheres to the fibers of the material attaches. 93386

Description

Process for processing materials containing fibers

The invention relates to a method for processing materials containing fibers as well as materials and systems obtainable by this method. The invention further relates to the use of a mixture containing a polymer for processing a material containing fibers, the use of dimethyl sulfoxide as an antioxidant in the processing of paper and the use of ionic liquids as an antimicrobial agent for processing paper.

Organic materials containing fibers, especially paper, undergo mechanical destabilization by degrading the fiber-forming macromolecules, such as cellulose macromolecules, over time. Especially in the case of paper, this can lead to destabilization of the paper to such an extent that the books from this paper can no longer be used. However, the problems of destabilization, especially aging, are not limited to paper and cellulosic materials in general, such as wood, but are generally a problem for materials containing fibers. In order to counteract this problem, appropriate processing methods for the material containing fibers needed. Paper, in particular printed paper in books, containing material as fibers makes this the highest demands on the processing method, which is why the further discussion on the example of paper, especially of printed paper should be done.

For paper documents, such as old manuscripts or old books, destabilization can make the paper fragile. This paper needs to be consolidated to reduce its brittleness.

When processing paper, especially printed paper in books, it is desirable that the processing method meet several requirements. On the one hand, the processing method should not only allow single-sheet processing. The method should rather be able to process several sheets at once. In this case, gluing the sides together should be avoided. In addition, if possible, the method should also not damage the binding of a book and / or the binding or back-sizing of the leaves. In this way, the process can be carried out more economically, since several sheets can be processed simultaneously or whole books at once and eliminates the separation of leaves from books. Furthermore, the method should not attack the paper in any other way, especially the paper should not swell irreversibly. Also, the ink and / or inks on the paper being processed should not be washed out by the process. At the same time, however, it is desirable that the processing of the paper is not only superficial, but ideally attaches to the entire paper. For the processing of paper, various methods have been developed. Good consolidation of paper can be achieved, for example, by splitting the damaged paper and re-adhering it together with a thin liner and a special adhesive containing cellulose ether and deacidifying agent. However, this processing is associated with a high manual effort and thus costly.

Also known is a method of solidifying paper by soaking the paper with acrylic acid derivatives which are caused to polymerize by irradiation with gamma rays. The irradiation with gamma rays, however, leads to a further damage to the paper, by impregnation with acrylic acid bleeding colors and inks on the paper, at least partially, and remaining in the paper residue monomers lead to an odor nuisance. Moreover, this method is difficult to combine with other common means of paper restoration.

Likewise, the processing of paper by lamination is known, wherein a thin polymer film or a thin stabilizing paper is applied to one side or both sides of the paper. In this single-sheet process, the processed paper stack often does not fit in the book cover after processing because of increasing paper thickness. In addition, the handle and the appearance of the paper are changed. Furthermore, the contrast decreases due to the applied layers. Furthermore, this method is difficult to combine with other conventional means of paper restoration.

A known method for processing paper is the so-called Viennese method, which is described in EP 0 273 9602 A2. In this process, the material to be processed is impregnated in an aqueous solution containing methylcellulose to strengthen the paper. Subsequently, the processing solution is pumped out, remnants of the processing solution are allowed to drip off the processed paper, and the paper is then snap-frozen and freeze-dried. The disadvantage of this method is mainly that book covers are damaged, which is why the leaves of the book must be removed before editing. In addition, a derivatized polymer must be used with methylcellulose.

DE 100 57 554 A1 describes a method in which the paper to be processed is coated with a silylated polymer derivative, such as e.g. silylated cellulose dissolved in a nonpolar solvent. The silyl groups are then split off by the action of moisture or water. A disadvantage of this method is the mandatory use of derivatized polymers.

EP 3 072 933 A1 describes alkaline nanoparticles comprising at least one hydroxide or carbonate or an organic compound of an alkaline earth metal and optionally a hydrophilic cellulose derivative and a stabilizing outer layer of hydrophobic polymers for deacidifying and consolidating cellulose-based artifacts. However, the nanoparticles must first be synthesized.

The methods known in the prior art have various disadvantages, such as the need for single sheet processing, side gluing, bleeding of inks and / or inks, odor nuisance, large increase in paper thickness, use of derivatized polymers, lack of compatibility with other conventional paper restorative agents, and the like Damage to book covers and / or back glues.

The object of the invention is therefore to provide a process for processing, in particular for strengthening, of material containing fibers, in particular paper, which at least partially overcomes one or more disadvantages of the processes known from the prior art. In particular, a method is desirable with which bulk processing of damaged paper can occur. The paper to be processed should not be damaged further. In particular, the paper to be processed should be consolidated. Any existing inks and inks should not bleed on the paper being processed. Furthermore, the covers and / or the paper back sizing should not be damaged by the process. In addition, it is desirable to be able to use simple-to-obtain substances such as polymers, which are in particular not derivatized, in the process.

This object is achieved according to the invention by the method of claim 1, the material containing fibers according to claim 19, the system of claim 20, the use of claim 21, the use of claim 23 and the use of claim 24.

Advantageous embodiments are specified in the subclaims and will be explained in detail below.

The method according to the invention for processing a material containing fibers comprises the following steps: a. Providing a mixture containing (i) at least one polymer and (ii) a polar aprotic solvent, b. bringing the material to be processed into contact with the material in step a. provided a mixture of the material and the in step a. to obtain the mixture obtained, c. Treat the in step b. obtained mixture so that at least a part of the polymer attaches to the fibers of the material. Surprisingly, it has been found that materials containing fibers can be processed very efficiently, effectively and safely for material consolidation and / or surface smoothing, in particular in the case of massive material application, using the method according to the invention.

A particular advantage of the process according to the invention is that by using a polar aprotic solvent it is also possible to use non-derivatized polymers, such as e.g. Cellulose can be used as the at least one polymer in the process according to the invention. Furthermore, by the use of a polar aprotic solvent mixtures, in particular solutions, can be produced with a low viscosity, which are particularly suitable for processing books or similar substrates. Surprisingly, despite the use of polymers, it is possible with the process according to the invention to avoid the sides becoming jammed. The use of the polar aprotic solvent further allows a wide range of possibilities to treat the mixture of the material to be processed containing fibers and the mixture, so that at least a part of the polymer attaches to the fibers of the material containing fibers. Furthermore, the process according to the invention can be combined with other processes, in particular deacidification processes.

If here or elsewhere "dissolution" is mentioned, in particular that a substance dissolves in a solvent, this may mean in particular that a solution of the substance can be prepared in the solvent which is at least 0.5 % By weight, in particular at least 1% by weight, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight or at least 10% by weight, and at most 25% by weight, in particular at most 20% by weight, 15% by weight, 14% by weight, 13% by weight or at most 12% by weight, in each case based on the total weight of the solution, of the substance.

If here or elsewhere "attachments", in particular of attaching a substance to another substrate, is mentioned, this may in particular mean precipitation, crystallization, deposition, growth and / or settling, in particular on the other substrate , The polymer may be wholly or partly attached to the material containing fibers, in particular to the fibers of the material containing fibers. When the polymer is only partially attached to the fibers of the material containing fibers, a residual amount of polymer remains in the mixture. By attachment, the fibers of the material containing fibers are preferably completely or partially encased. As a result, a consolidation of the fiber can be achieved. "Derivatized polymers" may be, in particular, those polymers obtained by a chemical modification of another polymer. The derivatization can also be reversible, so that the original polymer can be recovered. Derivatized polymers are made, for example, from naturally occurring polymers such as cellulose or starch. For example, the derivatized polymer methylcellulose can be obtained from underivatized cellulose by chemical modification. Other examples of underivatized polymers are starch, chitosan, chitin, lignin, viscose, pulp, silk and alginate. For derivatization, various chemical modifications are possible. The derivatization can be achieved, for example, by partial or complete alkylation, partial or complete acylation, partial or complete silylation, or partial or complete sulfonylation. "Material containing fibers" is also referred to hereinafter as "fibrous material" or "fiber-containing material".

The steps a. to c. The process of the invention are advantageously carried out in the order given.

With the method according to the invention, a wide variety of fibrous materials can be processed. The fibrous material may contain a polymer having at least one polar group, in particular in a proportion of 50 wt.%, 60 wt.%, 70 wt.%, 80 wt.%, 90 wt.%, 95 wt.%, 99 wt .%, or consist of. The at least one polar group may be contained in the polymer backbone and / or linked as a side chain with the polymer backbone. If several polar groups are included, they may be the same or different. Polar groups are known to the person skilled in the art. Examples of polar groups include the hydroxyl group, acid groups such as the carboxyl group and the sulfonic acid group, the amide group, the amine group, the thiol group, the ether group, in particular the C1-C4- Alkyl ether group, the ester group and the urethane group. In particular, the fibrous material may contain cellulose, microcrystalline cellulose, cellulose, hemicellulose, viscose, chitin, chitosan, alginate, starch, lignin, polyvinyl alcohol, proteins, or mixtures thereof. Other constituents of the fibrous material may be further polymers, in particular further polymers having at least one polar group, but also, for example, fillers such as calcium carbonate or pigments such as titanium dioxide. In particular, the fibrous material may be a cellulosic material, in particular paper, paperboard, cardboard, textiles or wood. According to a preferred embodiment of the invention, the fibrous material is paper, in particular paper sheets. Examples of paper are typewriter paper, printer paper, magazine paper, newsprint and book paper.

In the process of the invention, a mixture containing a polymer is provided. As a polymer, various polymers come into question. The polymer may be a copolymer or a homopolymer. In particular, the polymer may have a weight-average molecular weight Mw of from 1000 to 10 000 000 g / mol, in particular from 3000 to 10 000 000 g / mol, from 5000 to 500 000 g / mol or from 10 000 to 100 000 g / mol. The polymer may further contain at least one polar group. The at least one polar group may be contained in the polymer backbone and / or linked as a side chain with the polymer backbone. If several polar groups are included, they may be the same or different. Polar groups are known to the person skilled in the art. Examples of polar groups include the hydroxyl group, acid groups such as the carboxyl group and the sulfonic acid group, the amide group, the amine group, the thiol group, the ether group, in particular the C1-C4- Alkyl ether group, the ester group and the urethane group. In particular, the polymer may contain at least one hydroxyl group, at least one amine group, at least one acid group, in particular a carboxyl group, at least one amide group, at least one thiol group, at least one ether group, in particular a C1- C4 alkyl ether group, at least one ester group and / or at least one urethane group, in particular at least one hydroxyl group, and / or be selected from the group consisting of cellulose, alpha-cellulose, microcrystalline cellulose, pulp , Hemicellulose, viscose, chitin, lignin, chitosan, alginate, starch, silk, natural silk, silk biopolymers, polyvinyl alcohol, polyvinyl acetate, polyurethanes, polyamides, proteins, polymers or copolymers based on acrylic acid and / or its ester and / or amide Derivatives, methacrylic acid and / or its ester and / or amide derivatives, vinyl acetate, itaconic acid, maleic acid, fumaric acid, acryloxypropionic acid, methacryloxypropionic acid, styrenesulfone acid, ethyl methacrylate-2-sulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, phosphoethyl methacrylate, cellulose ethers and mixtures thereof. Preferably, the polymer is a non-derivatized polymer such as cellulose and / or viscose. The polymer preferably contains at least one hydroxyl group.

In particular, the polymer may be selected from the group consisting of cellulose, alpha-cellulose, microcrystalline cellulose, pulp, hemicellulose, viscose, chitin, lignin, chitosan, alginate, starch, silk, silk biopolymers, polyvinyl alcohol and mixtures thereof. Preferably, the polymer is selected from the group consisting of cellulose, alpha-cellulose, microcrystalline cellulose, pulp, silk, silk biopolymers, viscose, and mixtures thereof. Advantageously, the polymer is selected from the group consisting of cellulose, alpha-cellulose, microcrystalline cellulose, pulp, viscose and mixtures thereof. According to a preferred embodiment, the polymer is alpha-cellulose. According to a further preferred embodiment, the polymer is viscose, in particular substantially non-derivatized viscose. It has been shown that fiber-containing materials can be processed particularly well with the polymers mentioned above. In particular, by working with the above polymers good

Consolidations, in particular of cellulose-containing materials such as paper, cardboard, cardboard and wood, can be achieved.

The polymer can be used in particular in the form of fibers.

Viscose is composed in particular of regenerated cellulose. Viscose may be present in particular in the form of fibers. Viscose may in particular be a regenerated cellulose fiber, as described in EP 2 546 396 (see in particular paragraph [0026], [0028], [0029], [0030], [0031], [0032], [0033 ], [0034], [0035], [0036], [0037] and / or [0038]). Correspondingly, the viscose can be in the form of fibers which have a plurality of legs and in which at least one leg deviates in length from the other legs. In particular, it may be asymmetric cellulose fibers. The titer of the asymmetric cellulose fibers may be from 1.3 dtex to 10 dtex, in particular 3.3 dtex. The titre indicates the fineness, with 1 dtex in particular corresponding to a weight of one gram per 10000 meters of the cellulose fibers.

Silk biopolymers may in particular be silk biopolymers, as described in WO 2014/037453 or in WO 2011/113446. Accordingly, the silk biopolymers may in particular consist of polypeptides consisting essentially of one or more repeating polypeptide units and one or more non-repeating polypeptide units. The repeating polypeptide units may in particular contain oligoalanine units. The repeating polypeptide units can be the modules Ac (GPYGPGASAAAAAGGYGPGCGQQ), AK (GPYGPGASAAAAAGGYGPGKGQQ), Cc (GSSAAAAAAAASGPGGYGPENQGPCGPGGYGPGGP), CK1 (GSSAAAAAAASGPGGYGPENQGPKGPGGYGPGGP), CK2

(GSSAAAAAAAASGPGGYGPKNQGPSGPGGYGPGGP) or CKC (GSSAAAAAAAASGPGGYGPKNQGPCGPGGYGPGGP), where the parenthesized sequences represent amino acids in single letter code as described, for example, in the book "Enzymes - A Practical Introduction to Structure, Mechanism, and Data Analysis", 2nd Edition by Robert A. Copeland, Wiley-VCH, 2000, in Table 3.1 on page 45. The non-repeating polypeptide moieties can be prepared from the ηηη-repetitive (NR ) Units NR3, NR4, NR5, NR6 or the variants thereof described in WO 2014/037453.

The polymer in document a. The process of the invention may be the same or different than the polymer having at least one polar group which may be included in the fibrous material. For example, a cellulosic material may be contacted as a fibrous material with a mixture which also contains cellulose as a polymer. Likewise, however, a cellulosic material may be brought into contact as a fibrous material, for example with a mixture containing polyvinyl alcohol as a polymer. When the polymer contained in the mixture contains a polar group, the polar group of the polymer having at least one polar group which may be contained in the fibrous material and the polar group of the at least one polymer contained in the mixture may be the same or different. Thus, the fibrous material may be a cellulosic material and the polar polymer may be a polyurethane.

Suitable polar aprotic solvents in the process according to the invention are various solvents. In polar aprotic solvents, the molecules may have a dipole moment and / or the polar aprotic solvent may be composed of ions. Furthermore, polar aprotic solvents can be free of groups, in particular polar groups, from which protons can be split off. Examples of such groups are the OH group, acid groups such as the carboxyl group, the sulfonic acid group and hydrogen halide groups, the thiol group, and primary and secondary amines. Suitable polar aprotic solvents are, in particular, ketones, lactones, lactams, in particular N-alkylated lactams, nitriles, tertiary carboxylic acid amides, urea derivatives, in particular alkylated urea derivatives, sulfoxides, sulfones, carbonic esters, ionic liquids and / or mixtures thereof.

Examples of ketones are acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, cyclohexanone and their C1- to C4-alkylated derivatives.

Examples of lactones are propriolactone, gamma-butyrolactone, delta-valerolactone, epsilon-caprolactone and their C1- to C4-alkylated derivatives.

Examples of lactams are propiolactam, gamma-butyrolactam and their C1- to C4-alkylated derivatives.

Examples of alkylated lactams are N-methyl-propiolactam, N-methyl-2-pyrrolidone and their C1- to C4-alkylated derivatives.

Examples of nitriles are acetonitrile, propionitrile, butyronitrile, valeronitrile and their C1- to C4-alkylated derivatives.

Examples of tertiary carboxylic acid amides such as dimethylformamide, dimethylacetamide, dimethylpropionamide and their C1- to C4-alkylated derivatives.

Examples of urea derivatives, in particular alkylated urea derivatives, are dimethylpropyleneurea, tetramethylurea and their C1- to C4-alkylated derivatives.

Examples of sulfoxides are dimethylsulfoxide, ethylmethylsulfoxide, diethylsulfoxide and their C1- to C4-alkylated derivatives.

Examples of sulphones are sulfolane, ethylmethylsulfone and their C1- to C4-alkylated derivatives.

Examples of carbonic acid esters are dimethyl carbonate, ethylene carbonate, propylene carbonate, 1,2-butylene carbonate, 1,3-butylene carbonate and their C1- to C4-alkylated derivatives.

Examples of ionic liquids are given below.

Preferably, the polar aprotic solvent is selected from the group consisting of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethyl sulfoxide, acetone, gammabutyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate, ethylene carbonate, ionic liquids and mixtures thereof. In particular, the polar aprotic solvent is selected from the group consisting of dimethylacetamide, dimethyl sulfoxide, acetonitrile, ionic liquids and mixtures thereof. Polar aprotic solvents comprising a mixture of an ionic liquid and at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, acetone, gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate and ethylene carbonate, contain an ionic liquid.

The polar aprotic solvent may contain one or more ionic compounds, for example salts, inorganic salts and / or ionic liquids or in particular consist of one or more ionic liquids.

Suitable inorganic salts are, for example, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide or potassium iodide, in particular lithium chloride or lithium bromide and mixtures thereof. Inorganic salts may be present in an amount of 1 to 10% by weight, 3 to 8% by weight or 4 to 6% by weight, based in each case on the total amount of polar aprotic solvent and inorganic salt or inorganic salts. Accordingly, a polar aprotic solvent may be, for example, dimethylacetamide containing 5% by weight of lithium chloride.

Particularly good results can be achieved if the polar aprotic solvent contains an ionic liquid. Suitable ionic liquids are described in detail below. The polar aprotic solvent is preferably a mixture of an ionic liquid and at least one of dimethylacetamide, dimethyl sulfoxide and acetonitrile. According to a preferred embodiment, the polar aprotic solvent is a mixture of an ionic liquid and dimethylacetamide or dimethyl sulfoxide. According to a further preferred embodiment, the polar aprotic solvent is a mixture of an ionic liquid and dimethylacetamide. According to a further preferred embodiment, the polar aprotic solvent is a mixture of an ionic liquid and dimethyl sulfoxide.

With the abovementioned polar aprotic solvents, mixtures, in particular solutions, can be prepared with a wide variety of polymers. In particular, many poorly soluble polymers, in particular polymers containing at least one polar group, can readily dissolve in these polar aprotic solvents. If the polar aprotic solvent contains one or more ionic compounds, polymers comprising at least one polar group, in particular cellulose, can be better dissolved in them. In this way, mixtures, in particular solutions, with a content of, for example, 0.5 wt.%, 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, 6 wt. , 7 wt.%, 8 wt.%, 9 wt.%, 10 wt.%, 11 wt.%, 12 wt.%, 13 wt.%, 14 wt.% Or 15 wt.%, In each case based on the Total weight of the mixture to be obtained on polymer. As a result, the concentration of the polymer in a wide

Adjusted area to the needs of the fibrous material to be processed, which allows effective processing of the fibrous material.

The polar aprotic solvent may contain or consist of one or more ionic liquids. Suitable ionic liquids are, in particular, organic salts whose ions hinder the formation of a stable crystalline ligand through charge delocalization and steric effects. Ionic liquids have the particular advantage that many poorly soluble polymers such as cellulose dissolve well in them. Furthermore, ionic liquids can be well modified and adapted to different requirements.

If the polar aprotic solvent comprises an ionic liquid, the ionic liquid contains in particular a cation selected from a 1,3-dialkylimidazolium cation, an alkylpyridinium cation, a tetraalkylammonium cation and a phosphonium cation, and an anion selected from fluoride, chloride, bromide, iodide, formate, Acetate, propionate, butyrate, hydrogensulfate, tosylate, trifluoromethanesulfonate, bis (trifluoromethanesulfonyl) imide, hexafluorophosphate, tetrafluoroborate, benzoate, glycolate, thioglycolate, lactate and glycinate, or consists thereof. Preferably, the ionic liquid contains or consists of a dialkylimidazolium cation and an anion selected from chloride, bromide and acetate. The alkyl groups of the dialkylimidazolium cation may in particular be identical or different. The alkyl groups of the dialkylimidazolium cation may in particular be C1 to C10, in particular C1 to C5, alkyl groups. The alkyl groups of the dialkylimidazolium cation may be selected independently of one another preferably from the group consisting of methyl, ethyl, propyl and butyl. According to a preferred embodiment, the ionic liquid contains or consists of 1-butyl-3-methylimidazolium chloride and / or 1-butyl-3-methylimidazolium acetate.

The abovementioned cations and anions have the particular advantage that many polymers, in particular also sparingly soluble polymers such as cellulose, are readily soluble in ionic liquids which contain or consist of these cations and anions. Furthermore, in particular, the acetate anion has the advantage that the pH of fibrous materials having an acidic pH, which is brought into contact with a mixture in which the polar aprotic solvent contains an acetate anion-containing ionic liquid were, can be raised. This is particularly important in the processing of paper, as can be slowed down by an increase in the pH in the paper degradation of the cellulose fibers or even prevented.

The mixture containing at least one polymer and a polar aprotic solvent is preferably a homogeneous mixture, in particular a solution. Alternatively, in the mixture, the polymer may be solubilized or swollen by the polar aprotic solvent.

The provision of a mixture containing a polar aprotic solvent has, inter alia, the advantage that mixtures, in particular solutions, with a low viscosity can be obtained thereby. Such mixtures, in particular solutions, are particularly suitable for processing fibrous materials, in particular cellulosic materials such as paper. In this case, the mixture, in particular the solution, with which the fiber-containing material to be processed is brought into contact, in particular a viscosity of 0.01 to 100 mPa-s, preferably 0.1 to 70 mPa-s, preferably 0.5 to 50 mPas, more preferably 1 to 30 mPas, still more preferably 1 to 15 mPas. Mixtures, in particular solutions, having such viscosities are particularly suitable for processing fibrous materials, in particular cellulose-containing materials such as paper, since they can penetrate deeply into the fiber-containing material and thus not only a superficial attachment of the polymer is made possible. Methods for determining the viscosity of mixtures, in particular of solutions, are known to the person skilled in the art. In particular, the viscosity can be determined with a rotational viscometer "Gemini" from Bohlin at 25 ° C.

The contacting of the fibrous material with the mixture containing at least one polymer and a polar aprotic solvent can be carried out in various ways. For example, the fiber-containing material, in particular paper, may be sprayed or coated with the mixture, or the fiber-containing material, in particular paper, may be soaked in the mixture. Advantageously, the fibrous material is soaked in the mixture. If the fiber-containing material is soaked in the mixture, this may be for a period of 0.1 to 10 minutes, in particular 0.2 to 8 minutes, 0.2 to 7 minutes, 0.4 to 6 minutes, 0.5 to 5 Minutes, 0.5 to 4 minutes, 0.5 to 3 minutes or 0.5 to 2 minutes. This allows the at least one polymer to penetrate well into the fibrous material so that it can readily attach to the fibers of the material. Subsequently, the impregnated fibrous material with a polar aprotic solvent, in particular with dimethylacetamide and / or dimethyl sulfoxide, rinsed, in particular for a period of 10 to 60 seconds, 20 to 50 seconds or 25 to 40 seconds. By rinsing excess polymer can be removed.

The method of the invention comprises the step of treating the mixture of the fibrous material and the mixture containing at least one polymer and a polar aprotic solvent such that at least a portion of the polymer attaches to the fibers of the material. The treatment of the mixture can be designed in different ways. In particular, the treatment of the mixture in step c. be selected from the group consisting of contacting the mixture with an ionic compound, especially a salt, contacting the mixture with a nonionic compound, contacting the mixture with an acid, contacting the mixture with a base contacting the mixture with a polar solvent, contacting the mixture with a non-polar solvent, contacting the mixture with a solvent mixture, freeze-drying, lowering the temperature, evaporating the solvent, increasing the temperature, reducing the pressure and combinations thereof.

Examples of ionic compounds are salts or polymers having at least one ionic side group. In particular, salts consist of at least one cation and at least one anion, where the cation may be selected from cations selected from the group consisting of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba , Sc, Y, La, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag , Au, Zn, Cd, Hg, Al, Ga, In, Tl, Ge, Sn, Pb, and wherein the anion may be selected from anions consisting of elements of the group consisting of F, Cl, Br, I , O, S, Se, Te. Further examples of cations are ammonium ions. Further examples of anions are hydride, hydroxide, phosphates, phosphites, sulfates, sulfites, sulfides and carboxylates such as formate, acetate, proprionate, salicylate and benzoate. The salt may in particular contain ammonium sulfate or potassium sulfate or a mixture thereof. Examples of polymers having ionic side groups are polymers having at least one deprotonated acid group, in particular a deprotonated carboxyl group such as deprotonated polyacrylate, deprotonated polymethacrylate, polymers having at least one quaternary ammonium compound such as quaternized polydimethylaminoethyl methacrylate. The mixture can be brought into contact with the ionic compound by adding the salt directly or in the form of a solution, in particular an aqueous solution.

Examples of nonionic compounds are water, alcohols such as methanol, ethanol, propanol, butanol, octane, nonane, isocyanate-containing compounds, hydrocarbons having 1 to 20, in particular 5 to 18, carbon atoms, polymers such as polyether, polyester,

Polyamides, polyurethanes. These can be directly with the font in b. obtained mixture, for example by adding the respective non-ionic compound.

Examples of acids are hydrochloric acid, sulfuric acid, nitric acid, carboxylic acids having 1 to 20, in particular 1 to 10, carbon atoms, in particular formic acid, acetic acid, propionic acid and benzoic acid, and mixtures thereof. In particular, the acid may be selected from hydrochloric acid and carboxylic acids having 1 to 10 carbon atoms. These can be directly with the font in b. be brought into contact with the resulting mixture, for example by adding the respective acid, or by immersing the mixture in acid. The acid may be concentrated or diluted, for example as a dilute aqueous solution.

Examples of bases are hydroxide bases such as sodium hydroxide, potassium hydroxide, calcium hydroxide, amine bases such as, primary amines, secondary amines, tertiary amines, especially triethylamine, pyridine and dimethylaminopyridine, and mixtures thereof. These can be directly with the font in b. be brought into contact with the resulting mixture, for example by direct addition of the respective base. Alternatively, the respective base can also be used as a solution, in particular as an aqueous solution, with the in b. be brought into contact with the resulting mixture, for example by adding a solution, or by immersing the mixture in the solution.

Examples of polar solvents are water and alcohols such as methanol, ethanol, propanol and butanol, primary and secondary amines, carboxylic acids and mixtures thereof. In particular, the polar solvent may be water, an alcohol or a mixture thereof. These can be directly with the font in b. The resulting mixture can be brought into contact, for example by adding the polar solvent, or by immersing the mixture in the polar solvent.

Examples of non-polar solvents are hydrocarbons having 5 to 16 carbon atoms, benzene, toluene, pentane, hexane, heptane, cyclohexane, carbon tetrachloride, tetrachloroethene, trichloroethene, carbon disulfide, tetramethylsilane and hexamethyldisiloxane. The nonpolar solvent may in particular be hexamethyldisiloxane. These can be directly with the font in b. be brought into contact with the resulting mixture, for example by adding the polar solvent, or by immersing the mixture in the non-polar solvent. Solvent mixtures comprise, in particular, mixtures of the abovementioned polar and nonpolar solvents, in particular mixtures of hexamethyldisiloxane with other solvents, such as ethanol, methanol, propanol and butanol. These can be directly linked to the one in step b. be brought into contact with the resulting mixture, for example by adding the solvent mixture, or by immersing the mixture in the solvent mixture.

In freeze-drying, the mixture from step b. are first flash frozen and then dried at temperatures equal to or less than 0 ° C by applying a vacuum.

A temperature reduction can be carried out in particular to below the temperature at which polymer is poor or no longer soluble in the polar aprotic solvent. The temperature reduction may include a reduction to temperatures of -5 ° C to 15 ° C, especially 0 ° C to 10 ° C.

Upon evaporation, the temperature can be increased so that the polar aprotic solvent completely evaporates and leaves the polymer on the fibers of the material. The evaporation can be carried out at temperatures of 50 ° C to 250 ° C, in particular from 70 ° C to 200 ° C.

A temperature increase can be carried out at temperatures of 50 ° C to 200 ° C, in particular from 70 ° C to 150 ° C. The temperature increase can be gradual or abrupt.

The pressure reduction can be carried out at pressures of 0.1 mbar to 900 mbar, in particular from 1 mbar to 800 mbar, 10 mbar to 700 mbar or 50 mbar to 500 mbar. The pressure reduction can be combined in particular with the temperature increase and the temperature reduction.

Also, the lowering of the temperature may particularly be brought into contact with an ionic compound which may be contacted with a nonionic compound which may be contacted with an acid which may be contacted with a base which is in contact with a polar solvent which may be combined with a non-polar solvent and contacted with a solvent mixture.

Preferably, the treatment of the mixture in step c. the contact with a non-polar solvent, in particular the immersion in a non-polar solvent, in particular hexamethyldisiloxane, or consists thereof. Optimal results have been obtained when the mixture of the fibrous material and the mixture containing at least one polymer and a polar aprotic solvent was contacted with hexamethyldisiloxane, in particular dipped in hexamethyldisiloxane.

The aforementioned treatment options allow an attachment of the polymer to the fibers of the material containing fibers. Better results were achieved when the attachment was as slow as possible. This can be achieved in particular by treating the mixture of the fibrous material and the mixture containing at least one polymer and a polar aprotic solvent for at least a period of 15 seconds, in particular 30 seconds, 1 minute, 5 minutes, 15 minutes, 30 Minutes, 45 minutes, 1 hour, 5 hours, 10 hours, 15 hours or 24 hours and at most for a period of 150 hours, in particular 144 hours, 120 hours, 100 hours, 96 hours, 90 hours or 85 hours. Optimal results were obtained when the treatment in step c. over a period of 24 to 85 hours, in particular 50 to 80 hours or 65 to 75 hours or 72 hours. As a result, a slow attachment of the polymer to the fibers of the material containing fibers is achieved.

Advantageously, the treatment of the mixture of the fibrous material and the mixture containing at least one polymer and a polar aprotic solvent by contacting with a nonpolar solvent, in particular the immersion in a non-polar solvent, in particular hexamethyldisiloxane, over a period of 65 to 75 hours , especially 72 hours.

The process according to the invention may preferably also be carried out after the treatment in step c. the additional step of drying in step c. obtained fibrous material encompassed.

The drying of the step c. The fibrous material obtained by the process according to the invention is preferably carried out at 20 ° C to 100 ° C, in particular 30 ° C to 90 ° C, 40 ° C to 80 ° C, or 45eC to 65 ° C. The step c. The fibrous material obtained by the process according to the invention is preferably dried for 1 to 25 hours, in particular for 5 to 20 hours, 8 to 16 hours, 9 to 15 hours, 10 to 14 hours or 11 to 13 hours.

The method according to the invention can also be carried out before step a. the further step, that the material containing fibers, in particular paper, at a temperature of 40 to 80 ° C, in particular 45 to 70 ° C or 45 to 65 ° C is pre-dried. The predrying can be carried out for a period of 1 minute to 60 hours, in particular 1 hour to 50 hours or 12 to 48 hours.

The mixture containing at least one polymer and a polar aprotic solvent can be prepared in different ways. For example, the mixture may be prepared at room temperature or at lower or higher temperature, for example at 10 ° C to 150 ° C. The mixture can also be produced in several fonts. If the polar aprotic solvent contains an ionic liquid or if the polar aprotic solvent is a mixture of an ionic liquid and at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, acetone, gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea, dimethylpropyleneurea , Sulfolane, dimethyl carbonate and ethylene carbonate, in particular at least one of dimethylacetamide, dimethylsulfoxide and acetonitrile, the mixture containing at least one polymer and a polar aprotic solvent can be prepared in particular by first dissolving the polymer in the ionic liquid and then dissolving the resulting solution with at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, acetone,

Gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate and ethylene carbonate, in particular at least one of dimethylacetamide, dimethyl sulfoxide and acetonitrile, is diluted. Alternatively, the ionic liquid may first be treated with at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethyl sulfoxide, acetone,

Gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate and ethylene carbonate, in particular dimethyl sulfoxide, are mixed and then added the desired amount of the polymer.

The mixture containing at least one polymer and a polar aprotic solvent can in particular 1 to 30 wt.%, In particular 3 to 30 wt.%, 5 to 30 wt.%, 10 to 30 wt.%, 12 to 25 wt.% Or 15 to 20% by weight or 17 to 19% by weight of ionic liquid, in each case based on the total weight of the mixture. Mixtures with the above-mentioned contents of ionic liquids can be prepared well, in particular, solutions can easily be obtained in this way, which allow effective processing of the fibrous material.

The mixing, in particular the swelling, dissolving or dissolving, of the polymer and / or the subsequent dilution can take place at temperatures from 10 ° C to 150 ° C, in particular from 20 ° C to 140 ° C, 30 ° C to 130 ° C, 40 ° C to 120 ° C, 50 ° C to 110 ° C or 60 ° C to 100 ° C are performed. In this way, first a mixture, in particular a solution, with a concentration of the polymer of 5 to 20 wt.%, In particular from 7 to 15 wt.%, 8 to 13 wt.% Or 9 to 11 wt.%, Respectively on the total weight of the polymer and the ionic liquid in which ionic liquid is produced. This solution can then be treated in particular with at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethyl sulphoxide, acetone,

Gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate and ethylene carbonate, in particular at least one of dimethylacetamide, dimethyl sulfoxide and acetonitrile, are diluted to the desired concentration. Furthermore, the ionic liquid may also be mixed with at least one of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, acetone, at the abovementioned temperatures.

Gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea,

Dimethylpropyleneurea, sulfolane, dimethyl carbonate and ethylene carbonate, in particular dimethyl sulfoxide, with a concentration of the ionic liquid of 1 to 30 wt.%, In particular 3 to 30 wt.% Or 5 to 30 wt.% Or 10 to 30 wt.% Or 12 to 25 % By weight or 15 to 20% by weight or 17 to 19% by weight, in each case based on the total weight of the mixture, in particular of the ionic liquid and dimethyl sulfoxide. This solution can then be added to the polymer in the desired amount. In this way, the mixture containing at least one polymer and a polar aprotic solvent can be easily prepared. Furthermore, the concentration of the polymer in the mixture can thus be adjusted well.

Advantageously, the mixture containing at least one polymer and a polar aprotic solvent 0.1 to 10 wt.%, In particular 0.5 to 8 wt.% Or 1 to 5 wt.%, Based in each case on the total weight of the mixture of polymer. Solutions with these concentrations have in particular a suitable viscosity for the process according to the invention.

The invention further provides a material containing fibers, in particular paper, which is obtainable by the process according to the invention.

The invention further provides a system comprising at least two materials containing fibers obtainable by the process according to the invention, in particular a book.

The materials of the system of the invention may be the same or different. The fiber-containing materials may have been processed simultaneously or at different times by the process of the present invention. The system may further comprise materials, in particular materials containing fibers, which have not been processed by the method according to the invention.

The system may, in particular, be a book, a magazine, a journal or a newspaper. The fiber-containing material may in particular be paper. In particular, in a book, in addition to the paper, other fibers containing material, in particular cardboard, cardboard, textiles or wood, may be included.

If the system according to the invention contains materials containing various fibers, these can be processed separately or together by the process according to the invention. For example, in the case of a book, the paper can be edited separately from the rest of the book, especially separately from the cover. However, the book can also be edited without separating components beforehand, especially with its cover. Whether a separate processing of the components takes place can be decided in particular on the basis of how the fibers containing materials in the system, especially in the book, are held together. Examples of ways in which the fiber-containing materials can be held together in the system include thread stitching and adhesive binding.

The invention also provides the use of a mixture comprising at least one polymer and a polar aprotic solvent for processing material containing fibers, in particular paper, in particular in the process according to the invention.

For the use of the mixture, what has been said above for the polar aprotic solvent, for the material containing fibers and / or for the polymer, applies analogously.

The invention further provides the use of dimethyl sulfoxide as an antioxidant for processing paper, in particular in the process according to the invention.

The invention also provides the use of an ionic liquid containing a quaternary ammonium cation, in particular an ionic liquid containing a Dialkylimidazoliumkation, especially 1-butyl-3-methylimidazoliumchlorid or 1-butyl-3-methylimidazoliumacetat, as an antimicrobial agent for processing paper, especially in inventive method.

The attached figures show:

1 shows a fluorescence micrograph of a layer of a paper which has been processed according to the invention, wherein the polymer is fluorescently labeled

Cellulose was used and wherein the treatment was carried out by immersion of the paper soaked in the mixture in a mixture of hexamethyldisiloxane containing 1 vol.% Ethanol. The cellulose fibers of the substrate stand out very contrasty from the dark background.

FIG. 2 shows a fluorescence micrograph of a layer of a paper which has been processed according to the invention, wherein the polymer is fluorescence-marked

Cellulose was used and wherein the treatment was carried out by dipping the paper impregnated with the mixture in hexamethyldisiloxane. The cellulose fibers of the substrate stand out very contrasty from the dark background.

3 shows as a reference a fluorescence micrograph of a layer of unprocessed paper. The cellulose fibers of the substrate are to be distinguished from the background, but do not stand out as contrastingly from the background as the cellulose fibers in FIG. 1 or FIG. 2.

Fig. 4 shows a fluorescence micrograph of a layer of paper processed with a mixture containing no polymer. The cellulose fibers of the substrate are to be distinguished from the background, but do not stand out as contrastingly from the background as the cellulose fibers in FIG. 1 or FIG. 2.

The invention will be described in more detail below with reference to exemplary embodiments, which, however, serve only as an illustration and are not restrictive.

embodiments

Chemicals 1-Butyl-3-methylimidazolium chloride (BMIM-CI), Sigma-Aldrich; 1-butyl-3-methylimidazolium acetate (BMIM-OAc) obtained by anion exchange from BMIM-CI; Viscose (danufil, 3.3 dtex / 0.3 mm, hereafter: "Danufil"), Kelheim Fibers GmbH; Dimethylacetamide (DMAc), CSC Jäklechemie GmbH & Co. KG; Dimethyl sulfoxide (DMSO), CSC Jäklechemie GmbH & Co. KG; Hexamethyldisiloxane (HMDO), Chemische Fabrik Karl Bucher GmbH; microcrystalline cellulose (MCC), Sigma-Aldrich; Pulp (ENO PINE ECF); Stora Enso Oyj; alpha-cellulose, Sigma-Aldrich.

measurement methods

Measurements were made according to the following table.

Table 1: Measurement methods

All substrates were heated in an upstream step at 55 ° C for 24 hours unless otherwise stated. Since various papers have been used in the various examples, the papers used in various examples may have deviations in the measured values from each other, and therefore, only the values within an example can be directly compared with each other.

Example 1 (Processing of paper with viscose in a mixture of DMAc and BMIM-OAc)

First, a solution containing 10% by weight Danufil in BMIM-OAc was prepared, which was then diluted to a viscose content of 2% by weight based on the total weight of the solution by adding DMAc, the solution of BMIM-OAc and DMAc 18 wt% BMIM-OAc and 82 wt% DMAc, each based on the weight of BMIM-OAc and DMAc. The viscosity of the solution was 10 mPa-s. Subsequently, the paper to be processed was soaked in the prepared solution for one minute and then rinsed with DMAc for 30 seconds. The resulting paper was then immersed in HMDO (500 g) for 72 hours, whereby the viscose adhered to the paper fibers. After treatment in HMDO, the paper was heated at 55 ° C for 12 hours. The breaking force, elongation at break and pH of the treated paper 1 were then determined and compared to unprocessed paper for reference.

Table 2: Mechanical properties and pH value

Table 2 shows that the fracture strength, the elongation at break and the pH can be significantly increased when using mixtures containing viscose and mixtures of BMIM-OAc and DMAc by the inventive treatment compared to unprocessed paper. The processed paper was the optical and haptic impression equivalent to unprocessed paper. In particular, no bleeding of the ink was observed.

Example 2 (Processing of paper with viscose in a mixture of DMAc and BMIM-CI)

First, a solution containing 10% by weight of Danufil in BMIM-CI was prepared, which was subsequently diluted to a viscose content of 2% by weight, based on the total weight of the solution, of DMAc, the solution of BMIM-CI and DMAc 18 wt% BMIM-CI and 82 wt% DMAc, each based on the weight of BMIM-CI and DMAc. The viscosity of the solution was 10 mPa-s. Subsequently, the paper to be processed was soaked in the prepared solution for one minute and then rinsed with DMAc for 30 seconds. The resulting paper was then immersed in HDMO (500 g) for 72 hours, whereby the viscose was attached to the paper fibers. After treatment in HDMO, the paper was heated at 55 ° C for 12 hours. The breaking force, elongation at break and pH of the processed paper 2 were then determined and compared to unprocessed paper for reference.

Table 3: Mechanical properties and pH value

Table 3 shows that the breaking strength and the elongation at break when using mixtures containing viscose and mixtures of BMIM-CI and DMAc can be significantly increased by the inventive treatment compared to unprocessed paper. The processed paper was the optical and haptic impression equivalent to unprocessed paper. In particular, no bleeding of the ink was observed. Furthermore, the pH of the processed paper increased.

Example 3 (Processing of paper with MCC in 5% LiCl in DMAc)

First, a solution containing 2% by weight of microcrystalline cellulose in DMAc (containing 5% by weight of LiCl based on the total weight of LiCl and DMAc) based on the total weight of the solution was prepared. The viscosity of the solution was 13 mPa-s. Subsequently, the paper to be processed was soaked in the prepared solution for five minutes. The resulting paper was then immersed in HMDO (500 g) for 72 hours, whereby the viscose adhered to the paper fibers. After treatment in HMDO, the paper was heated at 55 ° C for 12 hours. The breaking force and elongation at break of the treated paper 3 were then determined and compared with a reference paper soaked in DMAc (containing 5% by weight of LiCl based on the total weight of LiCl and DMAc) for one minute, then for 72 hours in HMDO (500 g) was immersed and last heated at 60 ° C for 12 hours.

Table 4: Mechanical properties

Table 4 shows that the breaking strength as well as the elongation at break when using mixtures containing MCC and DMAc (containing 5% by weight LiCl) by the inventive treatment compared to paper that has not come into contact with a polymer such as MCC, is significantly higher. The processed paper was the optical and haptic impression equivalent to unprocessed paper. In particular, no bleeding of the ink was observed.

Example 4 (attachment by different treatments (step c.))

Test papers were impregnated with a solution according to Example 1 using MCC instead of viscose. After soaking in the solution, the papers were rinsed with DMAc as in Example 1 and dipped in the solvents listed in Table 5 for the indicated time.

Table 5: Treatments

After immersion in the solvents listed in Table 5, Test Papers 4 to 6 were heated at 55 ° C for 12 hours. While test paper 4 had a matte appearance, was flexible and was still stable even after repeated folding, test papers 5 and 6 partially showed a gloss. This indicates that in test paper 4, the MCC was deposited as above on the paper fibers, whereas in test papers 5 and 6 an inhomogeneous, rather superficial deposition of the MCC took place. Thus, by the choice of treatment, in particular by the choice of the solvent is immersed in it, the duration of the treatment and the addition of the polymer can be influenced.

Example 5 (comparison of different polymers)

Solutions were prepared according to Example 2, wherein the polymer specified in Table 6 were used as the polymer. Test papers were first soaked in the solution for five minutes. The respective test papers were then for 72

Hours immersed in HMDO (500 g), whereby the polymers indicated in Table 6 were each attached to the paper fibers. After treatment in HMDO, the test papers were heated at 55 ° C for 12 hours. The breaking force and breaking elongation of the processed papers were then determined.

Table 6: Mechanical properties

The reference sample in Table 6 was soaked in a mixture of BMIM-CI and DMAc without the polymer for five minutes and then dipped in HMDO for 72 hours and then heated at 55 ° C for 12 hours. It can be seen from Table 6 that the breaking strength has increased significantly as a result of the processing according to the invention in comparison to the reference paper, while the breaking elongation has fallen somewhat. Thus, the polymers mentioned above are suitable for the consolidation of paper in the process according to the invention.

Example 6 (combinability with deacidification method)

Solutions were prepared according to Example 1, in each of which a paper deacidified by the papersave process and a non-deacidified paper were soaked for one minute. After impregnation, the papers were rinsed with DMAc for 30 seconds, and the resulting papers were each immersed in HMDO (500 g) for 72 hours, whereby the viscose adhered to the paper fibers. After treatment in HMDO, the papers were heated at 55 ° C for 12 hours. The breaking force and elongation at break of the treated papers ("consolidated" or "deacidified / solidified" in Table 7) and a paper deacidified paper ("deacidified" in Table 7) were then determined. Also, the breaking force and elongation at break of the starting paper were determined ("reference" in Table 7), which was thus neither deacidified by the papersave method nor processed according to the inventive method.

Table 7: Mechanical properties

In the direct comparison, in the deacidification according to the papersave method, the breaking strength increases while the elongation at break decreases. In the method according to the invention no significant change in the breaking force was observed in this experiment, while the elongation at break increased significantly. In the sample, which was both deacidified and solidified, both the breaking force and the elongation at break increased significantly. Table 6 shows that the process according to the invention can be combined with deacidification processes such as the papersave process. In this case, in particular the increase in the elongation at break by the method according to the invention is of importance, since in this way the brittleness of papers can be reduced.

Example 7 (Application of various polymers to deacidified and non-deacidified substrate)

Solutions were prepared according to Example 1, wherein in each case the polymers indicated in Table 8 (non-deacidified papers) and Table 9 (papers deacidified by the papersave process) were used and the ionic liquid BMIM-CI was used. The test papers were soaked for one minute in each solution and then rinsed for 30 seconds with DMAc. The papers thus obtained were immersed in HMDO for 72 hours, whereby the polymers shown in Table 8 and 9, respectively, were attached to the paper fibers. After treatment in HMDO, the papers were heated at 55 ° C for 24 hours. The breaking force and breaking elongation of the processed papers were then determined. The reference paper was subjected to substantially the same processing as the other papers, except that the solution in the first step contained no polymer but only dimethylacetamide and BMIM-CI.

Table 8: Mechanical properties of processed non-deacidified papers

Table 9: Mechanical properties of processed, deacidified papers

Tables 8 and 9 show that, in particular, a higher breaking strength for deacidified and non-deacidified papers can be achieved by processing according to the process of the invention. For starch, an increase in elongation at break is also observed in the case of non-deacidified paper (see Table 8). The same applies to chitin in the case of deacidified paper (see Table 9). In addition to being able to be combined with the papersave process, it is therefore apparent from Tables 8 and 9 that the mechanical properties of the papers can be improved by the process according to the invention.

Example 8 (processing of wood)

It was prepared according to Example 2, a solution. This solution was applied to one side of a wooden board with a brush, rinsed with water and dried at 25 ° C for 16 hours. The surface of the wood shows at the machined places a clear smoothing of the surface. Paints can also be applied well on the processed areas.

Example 9 (Fluorescence Micrographs)

A solution containing 2% by weight of fluorescently labeled cellulose in a mixture of DMSO and BMIM-OAc, wherein the DMSO contained 20% by weight of BMIM-OAc, was prepared. Fluorescently labeled cellulose is known, for example, from W. Helbert et al. Biomacromolecules 2003, 4, 481-471, known. As a fluorescent marker, a DTAF marker was used, which is excited at 488 nm, the emission being measured at 515 nm. Two test papers were soaked in this solution for one minute and then rinsed with DMSO for 30 seconds. The first of these papers (Test Paper 7) was then dipped for 72 hours in HMDO containing 1 vol.% Ethanol (total 500 g). The second of these papers (Test Paper 8) was dipped in FIMDO (500 g) for 72 hours.

After treatment in HDMO or HMDO / ethanol, the papers were heated at 55 ° C for 12 hours. A blank was also prepared by first soaking a third test paper (Test Paper 9) in a mixture of DMSO containing 13% by weight BMIM-OAc without polymer, then immersing it in HMDO (500 g) for 72 hours and then at 55 ° C ° C was heated for 12 hours. The reference was a fourth test paper (test paper 10) which was not processed.

Of the test papers 7 to 10, several layers were successively removed with adhesive film at one point, wherein eight layers could be removed from the unprocessed reference and ten layers could be removed from the remaining processed test papers. The images were taken under the same microscope (Nikon FN-C LWD with Nikon lens 10x / 0.25) at 488 nm with the same exposure time (220 ms with Q-IMAGING RETIGA 200 RV). Representative images of the layers are shown in FIGS. 1 to 4.

Fig. 1 shows a recording of layer 3 of test paper 7. It can be clearly seen that the fibers of the paper stand out in a very high contrast from the background. FIG. 2 shows a photograph of layer 3 of test paper 8. It can be clearly seen that the fibers of the paper stand out in a very high contrast from the background. Fig. 3 shows a recording of layer 3 of the reference. The cellulose fibers are to be distinguished from the background, but do not stand out as contrastingly from the background as in Fig. 1 and Fig. 2. Fig. 4 shows a recording of layer 3 of the blank. Here, too, the cellulose fibers are to be distinguished from the background, but they do not stand out as contrastingly from the background as in FIG. 1 and FIG. 2.

The figures are consistent with an attachment of the fluorescently-labeled cellulose from the mixture to the fibers of the paper. So there was a kind of sheathing of paper fibers by the fluorescence-labeled cellulose, whereby the paper fibers and thus the paper are strengthened.

Example 10 (Editing a book)

A solution containing 1% by weight of alpha-cellulose in a mixture of DMSO and BMIM-OAc, wherein the DMSO contained 6.5% by weight of BMIM-OAc, and a solution containing 2% by weight of alpha-cellulose in a mixture from DMSO and BMIM-OAc, wherein the DMSO contained 11.3 wt% BMIM-OAc.

The substrate used was a 16-page 1943 book titled "Metalworking Table Book" which had been dried in a desiccator over orange gel over a period of one week, the moisture content of the book being 6.9% by weight. had fallen to 1.2 wt.%. The book was divided into three nearly equal parts by two horizontal cuts.

The middle part of the book was then fanned out in a vessel, after which the vessel was filled and closed with the solution described above containing 1% by weight of alpha-cellulose. The middle part of the book would be soaked in solution for 1 minute. The middle section of the book was then fanned out in a second vessel and rinsed with DMSO for 30 seconds. Subsequently, the middle part of the book was fanned out in a third vessel, after which the vessel was filled with HMDO and sealed. After 72 hours, the middle part of the book was taken, 6 hours at 55 ° C and dried for a week over orange gel in a desiccator.

The upper part of the book was processed like the middle part of the book with the difference that instead of the solution containing 1% by weight of alpha-cellulose, the solution containing 2% by weight of alpha-cellulose was used. The lower part of the book was not edited and served as a reference.

In analyzing the edited parts of the book, the following components of the parts of the book were examined: the cover sheet, which is the sheet forming the first and the last page; a center leaf, which in this case is the arch, which forms the 4th side from the front and the 4th side from the rear; the inner leaf, which is the arch that forms the two innermost sides. None of the components of the parts of the edited book showed any impairments due to the processing according to the invention. The color impression was almost unchanged. The mechanical properties of the various components of the processed book and the reference (lower unprocessed portion of the book) are listed in Tables 10 below (1% by weight of alpha-cellulose) and 11 (2% by weight of alpha-cellulose).

Table 10: Mechanical properties of the components of the middle part of the processed book (1% by weight of alpha-cellulose) and of the unprocessed lower part of the book (reference)

Table 11: Mechanical properties of the components of the upper part of the processed book (2% by weight of alpha-cellulose) and of the unprocessed lower part of the book (reference)

Tables 10 and 11 show more than a doubling of both breaking strength and elongation at break for all components of the machined parts of the book as compared to the unprocessed reference. Thus, books can be processed as a whole with the method according to the invention.

Example 11 (Comparison of DMSO and DMAc)

A solution containing 1% by weight of Danufil in a mixture of DMSO and BMIM-CI, wherein the DMSO contained 9.9% by weight of BMIM-Cl, (hereinafter: "DMSO solution") and a solution containing 1% by weight of water. % Danufil in a mixture of DMAc and BMIM-CI, wherein the DMAc contained 9.9 wt% BMIM-CI (hereinafter: "DMAc solution").

Test paper 11 was soaked in the DMSO solution for one minute, then rinsed with DMSO for 30 seconds, dipped in HMDO (500 g) for 72 hours, and then heated at 55 ° C for 12 hours.

Test paper 12 (blank test without Danufil) was soaked for one minute in DMSO containing 9.9 wt.% BMIM-CI, then rinsed with DMSO for 30 seconds, immersed in HMDO (500 g) for 72 hours and then at 55 ° C. for Heated for 12 hours.

Test paper 13 was soaked in DMSO for 1.5 minutes, then immersed in HMDO (500 g) for 72 hours and then heated at 55 ° C for 12 hours.

Test paper 14 was soaked in the DMAc solution for one minute, then rinsed with DMAc for 30 seconds, dipped in HMDO (500 g) for 72 hours and then heated at 55 ° C for 12 hours.

Test paper 15 (blank test without Danufil) was soaked for one minute in DMAc containing 9.9 wt.% BMIM-CI, then rinsed with DMAc for 30 seconds, immersed in HMDO (500 g) for 72 hours and then at 55 ° C for Heated for 12 hours.

Test paper 16 was soaked in DMAc for 1.5 minutes, then immersed in HMDO (500 g) for 72 hours and then heated at 55 ° C for 12 hours.

The reference was an unprocessed test paper.

The mechanical properties of the test papers 11 to 16 and the reference were determined and are listed in Tables 12 below.

Table 12: Mechanical properties of test papers 11 to 13 and the reference

From Table 12 it can be seen that test papers 11 and 14, which were contacted with a solution containing Danufil, had a higher breaking strength than test papers 12, 13, 15 and 16 and the reference not containing a solution containing Danufil® Were brought in contact. The values of the elongation at break of the test papers 11 to 16 differed only slightly. Furthermore, the test paper 11 to 16 compared to the reference both a significantly increased breaking strength and a significantly increased

Elongation at break, wherein the increase in the breaking force in the test papers 11 and 14, in which the test paper in each case with a solution containing Danufil was brought into contact, turned out to be the highest. Thus, this example also shows that by machining with the method according to the invention, the mechanical properties can be improved.

Furthermore, Table 12 shows that the breaking strength of test paper 11 is slightly higher than that of test paper 14. Accordingly, DMSO, in particular in combination with BMIM-CI and Danufil, appears to be somewhat better suited than DMAc in the process according to the invention, especially in combination with BMIM-CI and Danufil. For the elongation at break there was no significant difference between the test papers 11 and 14.

The above embodiments show that the mechanical properties of substrates such as paper can be improved by the method according to the invention. Furthermore, the pH of paper can be increased. Thus, the inventive method is, for example, for the preservation of books. Furthermore, other substrates such as wood can be subjected to the method according to the invention. This can be achieved, inter alia, a smoothing of surface irregularities, especially in massive material application. In addition, various polymers can be used in the process according to the invention. Furthermore, the process of the invention can be combined with paper deacidification processes such as the papersave process. Finally, the method is also suitable for editing books as a whole.

L

Claims (24)

A method of processing a material containing fibers, comprising the steps of: a. Providing a mixture containing (i) at least one polymer and (ii) a polar aprotic solvent, b. bringing the material to be processed into contact with the material in step a. provided mixture to a mixture of the material and in step a. to obtain the mixture obtained, c. Treat the in step b. obtained mixture so that at least a part of the polymer attaches to the fibers of the material. 2. The method according to claim 1, characterized in that the material contains cellulose, microcrystalline cellulose, cellulose, hemicellulose, viscose, chitin, chitosan, alginate, starch, lignin, polyvinyl alcohol, proteine or mixtures thereof. 3. The method according to claim 1 or 2, characterized in that the material is a cellulose-containing material, in particular paper, cardboard, textiles or wood, especially paper. 4. The method according to any one of the preceding claims, characterized in that the polymer is at least one hydroxyl group, at least one amine group, at least one acid group, in particular a carboxyl group, at least one amide group, at least one thiol group , at least one ether group, in particular a C 1 -C 4 -alkyl ether group, at least one ester group and / or at least one urethane group, in particular at least one hydroxyl group, and / or is selected from the group consisting cellulose, alpha-cellulose, microcrystalline cellulose, cellulose, hemicellulose, viscose, chitin, lignin, chitosan, alginate, starch, silk, natural silk, silk biopolymers, polyvinyl alcohol, polyvinyl acetate, polyurethanes, polyamides, proteins, polymers or copolymers based on acrylic acid and / or their ester and / or amide derivatives, methacrylic acid and / or their ester and / or amide derivatives, vinyl acetate, itaconic acid, maleic acid, fumaric acid, Acryloxypropionic acid, methacryloxypropionic acid, styrenesulfonic acid, ethylmethacrylate-2-sulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, phosphoethyl methacrylate, cellulose ethers and mixtures thereof. 5. The method according to any one of the preceding claims, characterized in that the polymer is selected from the group consisting of cellulose, alpha-cellulose, microcrystalline cellulose, pulp, viscose and mixtures thereof. 6. The method according to any one of the preceding claims, characterized in that the polymer is viscose, in particular substantially non-derivatized viscose. 7. The method according to any one of the preceding claims, characterized in that the polar aprotic solvent is selected from the group consisting of acetonitrile, dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, acetone, gamma-butyrolactone, N-methyl-2-pyrrolidone, tetramethylurea, dimethylpropyleneurea , Sulfolane, dimethyl carbonate, ethylene carbonate, ionic liquids and mixtures thereof. ) 8. The method according to any one of the preceding claims, characterized in that the polar aprotic solvent is selected from the group consisting of dimethylacetamide, dimethyl sulfoxide, acetonitrile, ionic liquids and mixtures thereof. 9. The method according to any one of the preceding claims, characterized in that polar aprotic solvent contains an ionic liquid. 10. The method according to any one of the preceding claims, characterized in that> the polar aprotic solvent is a mixture of an ionic liquid and at least one of dimethylacetamide, dimethyl sulfoxide and acetonitrile. 11. The method according to any one of claims 7 to 10, characterized in that the ionic liquid is a cation selected from a 1,3-Dialkylimidazoliumkation,> an alkylpyridinium cation, a tetraalkylammonium cation and a phosphonium cation, and an anion selected from fluoride, chloride, bromide, iodide, formate, acetate, propionate, butyrate, hydrogensulfate, tosylate, trifluoromethanesulfonate, bis (trifluoromethanesulfonyl) imide, hexafluorophosphate, tetrafluoroborate, benzoate, glycolate, thioglycolate, lactate and glycinate, or consists thereof. 12. The method according to any one of claims 7 to 11, characterized in that the ionic liquid contains a Dialkylimidazoliumkation and an anion selected from chloride, bromide and acetate or consists thereof. 13. The method according to any one of the preceding claims, characterized in that the treatment of the mixture in step c. selected from the group consisting of contacting the mixture with an ionic compound, especially a salt, contacting the mixture with a nonionic compound, contacting the mixture with an acid, contacting the mixture with a base contacting the mixture with a polar solvent, contacting the mixture with a non-polar solvent, contacting the mixture with a mixed solvent, freeze-drying, lowering the temperature, evaporating the solvent, increasing the temperature, depressurising and combinations thereof. 14. The method according to any one of the preceding claims, characterized in that the treatment of the mixture in step c. which comprises contacting or comprising a non-polar solvent, in particular dipping in a non-polar solvent, in particular hexamethyldisiloxane. 15. The method according to any one of the preceding claims, characterized in that the method after the treatment in step c. the additional step of drying in step c. obtained fibrous material. 16. The method according to any one of claims 9 to 15, characterized in that the mixture containing (i) at least one polymer and (ii) a polar aprotic solvent is prepared by first the polymer is dissolved in the ionic liquid and then the thus obtained Solution with at least one of dimethylacetamide, dimethyl sulfoxide and acetonitrile, especially dimethylacetamide, is diluted. 17. The method according to any one of claims 9 to 16, characterized in that the mixture containing (i) at least one polymer and (ii) a polar aprotic solvent 1 to 30 wt.%, In particular 3 to 30 wt.% Or 5 to 30 % By weight or 10 to 30% by weight or 12 to 25% by weight or 15 to 20% by weight or 17 to 19% by weight of ionic liquid, in each case based on the total weight of the mixture. 18. The method according to any one of the preceding claims, characterized in that the mixture containing (i) at least one polymer and (ii) a polar aprotic solvent 0.1 to 10 wt.%, In particular 0.5 to 8 wt.% Or 1 to 5 wt.%, Based in each case on the total weight of the mixture of polymer. 19. Material containing fibers, in particular paper, obtainable by a process according to one of claims 1 to 18. 20. System comprising at least two materials containing fibers according to claim 19, in particular a book. 21. Use of a mixture comprising (i) at least one polymer and (ii) a polar aprotic solvent for processing material containing fibers, in particular paper, in particular in a process according to one of claims 1 to 18. 22. Use according to claim 21, characterized in that the polar aprotic solvent is characterized by at least one feature of claims 7 to 12 and / or the polymer is characterized by at least one feature of claims 4 to 6. 23. Use of dimethyl sulfoxide as an antioxidant for processing paper, in particular in a method according to one of claims 1 to 18. 24. Use of an ionic liquid containing a quaternary ammonium cation, in particular an ionic liquid containing a Dialkylimidazoliumkation, in particular 1-butyl-3-methylimidazoliumchlorid or 1-butyl-3-methylimidazoliumacetat, as an antimicrobial agent for processing paper, in particular in a method according to one of claims 1 to 18. [λ.