Creping adhesive composition

Abstract

The invention relates to a creping adhesive composition and its use in the manufacture of tissue paper.

Description

Title of the invention: Creping adhesive composition Technical field of the invention

[0001] The invention relates to a creping adhesive composition and its use in the manufacture of tissue paper. Prior state of the art

[0002] In the tissue paper manufacturing process, the paper sheet is dried using a steam-heated drying cylinder called a Yankee. An adhesive is used to coat the surface of the Yankee to make the damp sheet adhere to the dryer. This improves heat transfer to the sheet, allowing for more efficient drying, and, most importantly, it ensures the sheet adheres properly for creping. Creping involves compressing the sheet against a blade, called a creping blade, to break the bonds between the fibers and form a micro-folded structure. Creping breaks a large number of fiber-to-fiber bonds in the sheet, giving it properties of bulk, stretch, absorbency, and softness. The degree of adhesion provided by the adhesive therefore plays an important role in the development of the tissue paper's properties.

[0003] The uniformity of the adhesive coating is also important, not only to ensure consistent creping, but also to ensure uniform coverage of the Yankee's surface and thus prevent premature wear of the cylinder and its blade. Indeed, premature wear of the creping blades necessitates their replacement, leading to paper machine downtime and therefore lost production.

[0004] Another important parameter is the durability of the coating. This is characterized by the stability of the coating on the surface of the Yankee. If the coating comes off easily, it does not protect the Yankee and leads to excessive wear. A hard coating causes the blade to chatter, which also leads to excessive wear. It is therefore preferable to use a soft but durable coating.

[0005] A quality Yankee coating corresponds to a uniform, flexible and durable film offering good adhesion for effective creping.

[0006] The most commonly used Yankee adhesives are synthetic polymers such as polyaminoamides, polyamides, polyamines, polyvinyl alcohols, polyvinyl acetates, polyacrylamides, and polyethers. In addition, various additives are used to modify the properties of the Yankee coating. Some examples of compositions, apparatus, and methods useful for obtaining crepe tissue paper are described in US patent documents 5,374,334 and 5,994,449.

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[0008]

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[0010]

[0011] US 6,663,942, US 5,660,687, US 6,207,011, WO 2006 / 048131, WO 2007 / 005577, US 2005 / 028954, US 2005 / 245669 and US 2005 / 006040. Even though many adhesives have been developed, there is still a need for a creping adhesive composition that provides better adhesion to the Yankee, reduces blade wear and is more durable to ensure better execution of the tissue paper manufacturing process. The Plaintiff discovered a new Yankee adhesive composition offering better adhesive properties while maintaining a flexible coating. The use of the creping adhesive composition according to the invention reflects a growing awareness of environmental concerns and the impact of industry and humankind on the planet. The composition offers superior performance compared to commonly used adhesives, thereby reducing the amount of adhesive required in the tissue paper manufacturing process and consequently lowering overall greenhouse gas emissions such as CO2. Description of the invention The present invention relates to a creping adhesive composition comprising: A / at least one PI polymer and at least one P2 polymer; said at least one PI polymer and at least one P2 polymer representing between 10 and 60% by weight of the adhesive composition; and B / at least one hydrophilic solvent representing between 40 and 90% by weight of the adhesive composition; (i) the PI polymer, having a molecular weight between 50,000 and 950,000 g / mol, chosen from the group consisting of: * polyamines obtained by Hofmann rearrangement on a PB1 base polymer of at least one monomer chosen from the group consisting of acrylamide, methacrylamide and their mixtures; * polyamines obtained by hydrolysis of the -N(R2)-CO-R' amide groups of a PB2 base polymer of at least one monomer of formula (I); and [Chem.l]

[0012] (I) in which: R1 and R2 are, independently, a hydrogen atom or an alkyl chain having from 1 to 6 carbon atoms; and * of their mixtures, ii) the P2 polymer, having a molecular weight between 1,500 and 500,000 g / mol, chosen from the group consisting of: * polyethyleneimines obtained by polycondensation of ethylene dichloride with ammonia, * polyethyleneimines obtained by polycondensation of aziridine, and * their mixtures.

[0013] The present invention also relates to a method for manufacturing tissue paper comprising the use of said creping adhesive composition. Description of the invention

[0014] The term "tissue paper" refers to toilet paper, kitchen paper, and other absorbent paper products for household use, for example, toilet paper, facial tissues, hand towels, paper towels, paper napkins, and paper finger wipes. For clarity in describing the invention, the term "tissue paper" is used to refer to "tissue paper and tissue products" as defined by ISO 12625-1.

[0015] The term "polymer" refers to a homopolymer or a copolymer. A homopolymer is a polymer composed of a single identical repeating unit, and a copolymer is composed of two repeating units. The polymer is obtained by polymerizing one or more monomers. The monomer(s) are selected from anionic hydrophilic monomers, cationic hydrophilic monomers, nonionic hydrophilic monomers, zwitterionic hydrophilic monomers, hydrophobic monomers, and mixtures thereof.

[0016] By "hydrophilic monomer" is meant a monomer which has an octanol / water partition coefficient, Kow, less than or equal to 1, in which the partition coefficient Kow is determined at 25 °C in an octanol / water mixture having a volume ratio of 1 / 1, at a pH between 6 and 8.

[0017] By "hydrophobic monomer" is meant a monomer which has an octanol / water partition coefficient, Kow, greater than 1, in which the partition coefficient Kow is determined at 25 °C in an octanol / water mixture having a volume ratio of 1 / 1, at a pH between 6 and 8.

[0018] The octanol / water partition coefficient, Kow, represents the ratio of the concentrations (g / L) of a monomer between the octanol phase and the aqueous phase. It is defined as follows:

[0019] [Math.l] [rnoHowzère] _ , ____ L ~ — \mommère\eau

[0020] By "water-soluble polymer" is meant a polymer which gives an aqueous solution without insoluble particles when dissolved under stirring at 25 °C and with a concentration of 10 gL 1 in deionized water.

[0021] By "X and / or Y" means "X", or "Y", or "X and Y".

[0022] Also part of the invention are all possible combinations of the various disclosed embodiments, whether preferred or given by way of example. Furthermore, where ranges of values ​​are indicated, the bounds are included in those ranges. The disclosure also includes all combinations of the bounds of those ranges of values. For example, the ranges of values ​​"1-20, preferably 5-15" imply the disclosure of the ranges "1-5", "1-15", "5-20", and "15-20", and the values ​​1, 5, 15, and 20.

[0023] The molecular weight is determined by the intrinsic viscosity of the polymer. The intrinsic viscosity can be measured by methods known to those skilled in the art and can be calculated from the reduced viscosity values ​​for different polymer concentrations by a graphical method consisting of plotting the reduced viscosity values ​​(ordinate axis) against the concentration (abscissa axis) and extrapolating the curve down to zero concentration. The intrinsic viscosity value is plotted on the ordinate axis or using the least squares method. The molecular weight can then be determined by the Mark-Houwink equation: [î]] = KM “ [r|] represents the intrinsic viscosity of the polymer determined by the solution viscosity measurement method. K represents an empirical constant. M represents the molecular weight of the polymer, and a represents the Mark-Houwink coefficient. K and a depend on the specific polymer-solvent system. Crepe adhesive composition: Polymer PI

[0024] The PI polymer has a molecular weight between 50,000 and 950,000 g / mol. The PI polymer comprises at least one monomer obtained: by Hofmann rearrangement on a PB1-based polymer of acrylamide, methacrylamide, or mixtures thereof; or by hydrolysis of the N-(R2)-CO-R' amide groups of a PB2-based polymer of at least one monomer of formula (I); and mixtures thereof:

[0025] [Chem.l] (I)

[0026] in which: R1 and R2 are, independently, a hydrogen atom or an alkyl chain having from 1 to 6 carbon atoms.

[0027] The Hofmann rearrangement on the base polymer PB1 and the hydrolysis of the -N(R2)-CO-R' amide groups of the base polymer PB2 produce vinylamine monomer units.

[0028] The amines obtained by Hofmann rearrangement or hydrolysis of amide groups can be in neutral form (i.e. uncharged or ionic) or ionic form (i.e. in ammonium form).

[0029] In other words, the term “amine” encompasses both the neutral form and the ionic form (i.e., ammonium).

[0030] Hofmann rearrangement of the base polymer PB1

[0031] The Hofmann rearrangement consists of converting amide functions into amine functions (for example by forming vinylamine monomer units) by involving two main coefficients (expressed in molar ratios): - Coefficient Alpha = hypohalide (alkali metal hypohalide and / or alkaline earth metal hypohalide) / amide functions; - Beta coefficient = hydroxide (alkali metal hydroxide and / or alkaline earth metal hydroxide) / hypohalide (alkali metal hypohalide and / or alkaline earth metal hypohalide).

[0032] A "hypohalide" is an oxy-anion, for example hypochlorite CIO₃. Preferably, it is sodium hypochlorite.

[0033] An "alkali metal hypohalide" is a hypohalide of at least one alkali metal, for example NaOCl, KOBr or NaOCl+KOBr. The same applies to an alkali-earth hypohalide.

[0034] The alkali metal is advantageously chosen from: lithium, sodium or potassium.

[0035] The alkaline earth metal is advantageously chosen from: calcium or magnesium.

[0036] An "alkali hydroxide" refers to a compound containing a hydroxide anion (OH⁻) and an alkali metal, for example NaOH, KOH, or a mixture thereof (NaOH + KOH). The same applies to an alkaline earth hydroxide. Preferably, this refers to sodium hydroxide.

[0037] The term "hydroxide" used below refers to both an "alkali hydroxide" and an "alkali-earth hydroxide".

[0038] Advantageously, the Hofmann rearrangement comprises at least the following steps: i) dilution, advantageously in water, of the solution comprising the base polymer PB1, in order to form a dilute solution SD1 of the polymer with amide functions; ii) addition of the hypohalide and the hydroxide, in order to form a dilute solution (SD2); iii) reaction between the base polymer PB1, the hypohalide and the hydroxide; iv) obtaining a solution comprising the PI polymer (SD3).

[0039] Advantageously, in step i), the concentration of the base polymer PB1 in the dilute solution SD1 is between 1 and 40% by weight relative to the weight of the solution SD1, preferably between 2 and 30%, more preferably between 5 and 25%.

[0040] Advantageously, in step ii), the Alpha coefficient is between 0.1 and 1.0, preferably between 0.3 and 1.0, and more preferably between 0.5 and 1.0.

[0041] Advantageously, in step ii), the Beta coefficient is between 0.5 and 4.0.

[0042] Advantageously, in step iii), the reaction between the base polymer PB1, the hypohalide and the hydroxide lasts between 10 seconds and 180 minutes, preferably between 1 minute and 120 minutes, more preferably between 10 minutes and 90 minutes, and even more preferably between 30 minutes and 75 minutes.

[0043] Advantageously, in step iii), the reaction between the base polymer PB1, the hypohalide and the hydroxide is carried out at a temperature between 10 and 30 °C, preferably between 15 and 25 °C.

[0044] At the end of step iii), the PI polymer is obtained.

[0045] In order to stabilize the amine functions of the PI polymer obtained following the rearrangement, those skilled in the art may add at least one quaternary ammonium derivative as described in document JP 57077398. This quaternary ammonium derivative is intended to prevent the reaction between the amine functions and the residual amide functions. The addition of these agents may be carried out separately, simultaneously, mixed or not, in any order of introduction, and at one or more injection points. Advantageously, the addition of these agents is carried out in step i).

[0046] During the Hofmann rearrangement, the cationicity of the polymer increases by reuse / consumption, in whole or in part, of an alkali or alkaline earth hypohalide.

[0047] PI advantageously has a percentage of amide functions (acrylamide and / or methacrylamide) rearranged into amine functions of between 1 and 100 mol%, preferably between 10 and 90 mol%, more preferably between 20 and 80 mol%, more preferably between 30 and 70 mol%, and even more preferably between 40 and 60 mol%, relative to the total number of moles of acrylamide and / or methacrylamide of the base polymer PB1.

[0048] Thus the Hofmann rearrangement can be total or partial.

[0049] Thus, in the case of the Hofmann rearrangement, "polyamine" means a polymer comprising amine functions (total Hofmann rearrangement = 100%) or a mixture of residual amine and amide functions.

[0050] Hydrolysis of the monomer of formula (I) of the base polymer PB2

[0051] Advantageously, the monomer(s) of formula (I) are selected from: N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide, N-vinyl-N-ethylacetamide, N-vinylpropanamide, N-vinyl-N-methylpropanamide, N-vinylbutyramide and mixtures thereof. Preferably, it is N-vinylformamide.

[0052] The hydrolysis of the monomer of formula (I) can be carried out under the action of an acid (acid hydrolysis) or a base (basic hydrolysis). Preferably, it is a basic hydrolysis.

[0053] Acid hydrolysis can be carried out using any acid known to a person skilled in the art, by way of example and without limitation, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid may be mentioned in particular.

[0054] Acid hydrolysis is advantageously carried out at a pH between 0 and 2, preferably between 0 and 1.

[0055] Acid hydrolysis is advantageously carried out at a temperature between 60 and 100 °C, preferably between 70 and 90 °C, more preferably between 75 and 85 °C.

[0056] The duration of the acid hydrolysis step is advantageously between 120 minutes and 720 minutes, preferably between 180 minutes and 600 minutes, more preferably between 300 minutes and 540 minutes.

[0057] Basic hydrolysis can be carried out using any base known to a person skilled in the art, by way of example and without limitation, sodium hydroxide, potassium hydroxide, ammonia may be mentioned in particular.

[0058] Basic hydrolysis is advantageously carried out at a pH between 8 and 14, preferably between 8 and 13, more preferably between 9 and 12.

[0059] Basic hydrolysis is advantageously carried out at a temperature between 60 and 100 °C, preferably between 70 and 90 °C, more preferably between 75 and 85 °C.

[0060] The duration of the basic hydrolysis step is advantageously between 60 minutes and 480 minutes, preferably between 120 minutes and 420 minutes, more preferably between 240 minutes and 360 minutes.

[0061] Depending on the amount of acid or base added, the amide groups -N(R2)-CO-R' of the base polymer PB2 are partially or totally converted into amine.

[0062] PI advantageously has a degree of hydrolysis between 1 and 100 mol%, preferably between 10 and 90 mol%, more preferably between 20 and 80 mol%, more preferably between 30 and 70 mol%, and even more preferably between 40 and 60 mol%, relative to the total number of moles of the amide -N(R2)-CO-R' groups of the base polymer PB2.

[0063] Thus the hydrolysis of amide groups into amine can be total or partial.

[0064] Thus, in the case of hydrolysis, "polyamine" means a polymer including amine functions (total hydrolysis = 100%) or a mixture of residual amine and amide functions.

[0065] Once the hydrolysis reaction is complete, the pH is advantageously adjusted between 6 and 9.

[0066] In a particular mode, the PI polymer (and therefore the base polymer PB1 or PB2) comprises at least one monomer having a quaternary amine function.

[0067] Advantageously, the monomer(s) having a quaternary amine function are chosen from monomers derived from vinyl-type units (advantageously acrylamide, acrylic, allylic, or maleic), these monomers having a quaternary ammonium function. In particular, and without limitation, examples include diallyldialkyl ammonium salts such as diallyl dimethyl ammonium chloride (DADMAC); quaternary dialkylaminoalkylacrylamides salts; Quatemized salts of dialkyl-aminoalkyl methacrylamides, such as methacrylamido-propyl trimethyl ammonium chloride (MAPTAC), acrylamido-propyl trimethyl ammonium chloride (APTAC), quatemized salts of dialkyl aminoalkyl acrylates, such as quaternized dimethylaminoethyl acrylate, quaternized salts of dialkyl aminoalkyl methacrylates, such as quaternized dimethylaminoethyl methacrylate, and mixtures thereof. Advantageously, the alkyl groups are in the C1-C3 position.Preferably, the monomer having a quaternary amine function is diallyl dimethyl ammonium chloride (DADMAC).

[0068] A person skilled in the art will know how to prepare the quaternized monomers, for example by means of quaternizing agent of type RX, R being an alkyl group and X being a halogen or a sulfate.

[0069] By “quaternizing agent” is meant a molecule capable of alkylating a tertiary amine.

[0070] The quaternizing agent may advantageously be chosen from dialkyl sulfates comprising from 1 to 6 carbon atoms or alkyl halides comprising from 1 to 6 carbon atoms. Preferably, the quaternizing agent is chosen from methyl chloride, benzyl chloride, dimethyl sulfate, or diethyl sulfate. Furthermore, the present invention also covers DADMAC, APTAC, and MAPTAC type monomers in which the counterion is a sulfate, a fluoride, a bromide, or an iodide instead of a chloride.

[0071] The PI polymer (and therefore the base polymer PB1 or PB2) advantageously comprises at least 25 mol% of monomer having a quaternary amine, preferably at least 35 mol% and more advantageously at most 50 mol%.

[0072] The PI polymer (and therefore the base polymer PB1 or PB2) may also contain at least one monomer A selected from hydrophilic non-ionic monomers, hydrophilic anionic monomers, hydrophilic zwitterionic monomers and hydrophobic monomers.

[0073] Advantageously, the PI polymer (and therefore the base polymer PB1 or PB2) comprises less than 30 mol% of monomer A, preferably less than 20 mol%.

[0074] Advantageously, the non-ionic hydrophilic monomer(s) are chosen, in particular, from the group comprising water-soluble vinyl monomers, such as N-alkylacrylamides, N-alkylmethacrylamides, N,N-dialkyl acrylamides (for example, N,N-dimethylacrylamide or N,N-diethylacrylamide), N,N-dialkylmethacrylamides, alkoxylated esters of acrylic acid, alkoxylated esters of methacrylic acid, N-vinylpyrrolidone, N-methylol(meth)acrylamide, acryloyl chloride, N-vinyl caprolactam, N-vinyl imidazole, N-vinyl succinimide, acryloyl morpholine (ACMO), glycidyl methacrylate, glyceryl methacrylate, the diacetone acrylamide, methacrylic anhydride, maleic anhydride, itaconic anhydride, itaconamide, hydroxyalkyl (meth)acrylates, thioalkyl (meth)acrylates, isoprenol and its alkoxylated derivatives, hydroxyethyl (meth)acrylates and their alkoxylated derivatives,Hydroxypropylacrylate and its alkoxylated derivatives, vinyl acetate, and mixtures thereof. Among these non-ionic monomers, the alkyl groups are advantageously in the C1-C5 position, more advantageously in the C1-C3 position. They are preferentially linear alkyls.

[0075] When the PI polymer is obtained by hydrolysis of the -N(R2)-CO-R' amide groups of the base polymer PB2, the PI polymer (and therefore the base polymer PB2) may further comprise as non-ionic hydrophilic monomers acrylamide, methacrylamide, acrylonitrile and mixtures thereof.

[0076] Advantageously, the other hydrophilic anionic monomer(s) can be chosen from a wide range. These monomers may have a vinyl functional group, in particular acrylic, maleic, fumaric, malonic, itaconic, or allylic. They may also contain a carboxylate, phosphonate, phosphate, sulfonate, or other anionically charged group. Preferred monomers belonging to this class are, for example, acrylic acid, methacrylic acid, dimethylacrylic acid, itaconic acid, the Ci-C3 hemi-esters of itaconic acid, crotonic acid, maleic acid, fumaric acid, 3-acrylamido-3-methylbutanoic acid, strong acid-type monomers exhibiting, for example, a sulfonic acid or phosphonic acid function such as vinylsulfonic acid, vinylphosphonic acid, allylsulfonic acid, methallylsulfonic acid, 2-methylidenepropane-1,3-disulfonic acid, 2-sulfoethyl methacrylate,Sulfopropyl methacrylate, sulfopropyl acrylate, allylphosphonic acid, ethylene glycol methacrylate phosphate, styrene sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid (ATBS), 2-acrylamido-2-methylpropane disulfonic acid, 3-allyloxy-2-hydroxypropane sulfonic acid, diethylallylphosphonate, carboxyethyl acrylate; the water-soluble salts of all these monomers, such as their alkali metal, alkaline earth metal, or ammonium salts; and mixtures thereof. Also included are the hemiesters of maleic acid or itaconic acid, their salts, and mixtures thereof.

[0077] In a particular mode, the anionic hydrophilic monomer(s) may be salified. It may also be a mixture of acidic and salified forms, for example a mixture of acrylic acid and acrylate.

[0078] By salification, we mean the substitution of a proton of at least one acidic functional group of the type -Ra(=O)-OH (with R = P, S, or C) of the anionic monomer by a metal or organic cation to form a salt of the type -Ra(=O)-OX (X being a metal or organic cation). In other words, the unsalified form corresponds to the acidic form of the monomer, for example Rb-C(=O)-OH in the case of the carboxylic acid functional group, while the salified form of the monomer corresponds to the form Rb-C(=O)-0 X+, X+ corresponding to an alkali or organic cation. The salification of the acidic functional groups of the polymer may be partial or complete.

[0079] The salt form is advantageously suited to alkali metal salts (Li, Na, K..of alkaline earth metals (Ca, Mg..and the organic cation is advantageously the ammonium ion or a tertiary ammonium. The preferred salts are sodium salts.

[0080] Salification can take place before or after polymerization.

[0081] The PI polymer (and therefore the base polymer PB1 or PB2) may also include hydrophilic zwitterionic monomers and / or hydrophobic monomers.

[0082] When the PI polymer (and therefore the base polymer PB1 or PB2) comprises one or more hydrophobic monomers, the proportion is less than 5% by moles (relative to the total number of moles of monomers) and their quantity is adjusted so that the polymer remains soluble in water.

[0083] In a preferred mode, the PI polymer (and therefore the base polymer PB 1 or PB2) is devoid of hydrophobic monomer.

[0084] The quantities of the different monomers will be adjusted by a person skilled in the art so as not to exceed 100% molar during the preparation of the PB1 and PB2 base polymers.

[0085] The PI polymer advantageously has an average molecular weight between 50,000 g / mol and 950,000 g / mol, preferably between 100,000 g / mol and 750,000 g / mol, more preferably between 150,000 g / mol and 500,000 g / mol.

[0086] The PI polymer may further comprise at least one branching agent. A branched polymer is a non-linear polymer with side chains. The structuring of the PI polymer is advantageously carried out during the preparation of the base polymer PB1 or PB2.

[0087] The branching agent is advantageously chosen from: - Structuring agents, which may be chosen from the group comprising monomers with polyethylene unsaturation (having at least two unsaturated functions), such as vinyl functions, particularly allylic or acrylic, and examples include methylene bisacrylamide (MBA), triallyamine, tetraallylammonium chloride, 1,2-dihydroxyethylene bis-(N-acrylamide), ethylene glycol (meth)acrylate, - monomers having at least two epoxy functions, - monomers having at least one unsaturated function and one epoxy function, - macroinitiators such as polyperoxides, polyazo compounds, and polytransfer agents such as polymer-capturing polymers and polyols, - functionalized polysaccharides, - water-soluble metal complexes composed of: * of a metal with a valence greater than 3 such as, by way of example and without limitation, aluminium, boron, zirconium or titanium, and * of a ligand bearing a hydroxyl function.

[0088] In a preferred mode, the PI polymer is devoid of a branching agent.

[0089] In a particular mode, the PI polymer (advantageously the PB1 base polymer) or PB2) includes a transfer agent.

[0090] The transfer agent is advantageously selected from methanol, isopropyl alcohol, sodium hypophosphite, calcium hypophosphite, magnesium hypophosphite, potassium hypophosphite, ammonium hypophosphite, formic acid, sodium formate, calcium formate, magnesium formate, potassium formate, ammonium formate, 2-mercaptoethanol, 3-mercaptopropanol, dithiopropylene glycol; thioglycerol; thioglycolic acid; thiohydracrylic acid; thiolactic acid; thiomalic acid; cysteine; aminoethanethiol; thioglycolates; Allyl phosphites; allylic mercaptans; sodium methallysulfonate; calcium methallysulfonate; magnesium methallysulfonate; potassium methallysulfonate; ammonium methallysulfonate; polythiols and mixtures thereof. Preferably, the transfer agent is sodium hypophosphite, sodium formate, or a mixture thereof.

[0091] In a particular mode, the PI polymer is devoid of a transfer agent. P2 Polymer

[0092] The polymer P2 is selected from: polyethyleneimines obtained by polycondensation of ethylene dichloride with ammonia and polyethyleneimines obtained by polycondensation of aziridine, and mixtures thereof.

[0093] Polyethyleneimines obtained by polycondensation of aziridine are advantageously prepared according to US documents 2,182,306 and US 3,251,778.

[0094] Polyethyleneimines are advantageously obtained by polycondensation of ethylene dichloride (EDC) with ammonia in the presence of a Brpnsted base.

[0095] Polycondensation is advantageously carried out by adding to an ammonia solution a flow of ethylene dichloride (EDC) and a Brpnsted base.

[0096] The Brpnsted base can be any base known to a person skilled in the art, in particular sodium hydroxide or potassium hydroxide.

[0097] In a preferred mode, the molar ratio between ethylene dichloride (EDC) and Brpnsted base is advantageously between 1:5 and 1:1, preferably between 1:3 and 1:1, more preferably between 1:2 and 1:1.

[0098] In a preferred mode, the molar ratio between ammonia and ethylene dichloride (EDC) is advantageously between 5:1 and 1:1, preferably between 3:1 and 1:1, more preferably between 2:1 and 1:1.

[0099] The polycondensation temperature is advantageously between 50 and 120 °C, preferably between 80 and 100 °C.

[0100] In a preferred mode, the aqueous ammonia solution is heated to the polycondensation temperature before the start of the pouring of ethylene dichloride (EDC) and Brpnsted base.

[0101] The duration of the polycondensation is advantageously between 60 minutes and 360 minutes, preferably between 120 minutes and 300 minutes, more preferably between 180 minutes and 260 minutes.

[0102] The polymer P2 advantageously has a weight average molecular weight of between 1,500 g / mol and 500,000 g / mol, preferably between 2,000 g / mol and 400,000 g / mol, more preferably between 2,500 g / mol and 300,000 g / mol, more preferably between 5,000 g / mol and 250,000 g / mol, more preferably between 10,000 g / mol and 200,000 g / mol, more preferably between 20,000 g / mol and 150,000 g / mol.

[0103] The polymer P2 may further comprise at least one branching agent.

[0104] Structuring can take place during polymerization or after polymerization on polymer P2. Preferably, structuring takes place after polymerization.

[0105] The branching agent is advantageously chosen from compounds having at least two epoxy groups. Examples include, but are not limited to, polyethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, and ethylene glycol diglycidyl ether. Preferably, it is polyethylene glycol diglycidyl ether.

[0106] The amount of branching agent in the polymer P2 is advantageously between 0.0001 and 1 mol% with respect to the number of amine functions present in the polymer P2, preferably between 0.001 and 0.1 mol%, more preferably between 0.01 and 0.05 mol%.

[0107] Polymer P2 has an amount of tertiary amine advantageously between 1 and 50 mol% relative to the total weight of amine functions in polymer P2, preferably between 2 and 45 mol%, more preferably between 5 and 40 mol%. Creping adhesive composition

[0108] The creping adhesive composition comprises: A / at least one PI polymer and at least one P2 polymer; said at least one PI polymer and at least one P2 polymer representing between 10 and 60% by weight of the adhesive composition; and B / at least one hydrophilic solvent representing between 40 and 90% by weight of the adhesive composition.

[0109] The hydrophilic solvent is advantageously water; it can also be a mixture of water and a water-miscible solvent such as alcohols (advantageously in CrC8) and / or ketones (advantageously in C3-C8). Preferably, the hydrophilic solvent is water.

[0110] When the hydrophilic solvent is a mixture of water and a water-miscible solvent, the miscible solvent advantageously represents less than 30% by weight of the hydrophilic solvent, preferably less than 20% by weight, more preferably less than 10% by weight.

[0111] The weight ratio between polymer PI and polymer P2 in the crepe adhesive composition is advantageously between 5:95 and 95:5, preferably between 10:90 and 90:10, more preferably between 20:80 and 80:20.

[0112] In a preferred mode, the total amount of primary amine in the PI and P2 (P1+P2) polymers is advantageously less than 75 mol% compared to the total amount of amine (primary + secondary + tertiary + ammonium) present in the PI and P2 (P1+P2) polymers, preferably less than 60 mol%, and advantageously greater than 10 mol%, preferably greater than 20 mol%.

[0113] In a preferred mode, the total amount of tertiary amine in the PI and P2 (P1+P2) polymers is advantageously less than 50 mol% compared to the total amount of amine (primary + secondary + tertiary + ammonium) present in the PI and P2 (P1+P2) polymers, preferably less than 45 mol%, and advantageously greater than 2 mol%, preferably greater than 5 mol%.

[0114] The creping adhesive composition according to the invention may further comprise one or more additives conventionally used in the tissue paper manufacturing process, for example, and without limitation, plasticizers, salt-protecting agents, biocides, pH modifiers...

[0115] Water-soluble polyols are particularly suitable plasticizing agents.

[0116] The water-soluble polyol is advantageously chosen from compounds having one or more alkylene groups and up to six hydroxyl groups, the alkylene groups optionally being interrupted by one or more O or NH groups. Preferred polyols include glycerol, ethylene glycol, 1,4-butanediol, diethanolamine, triethanolamine, sorbitol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, and polyethylene glycol. Preferably, the water-soluble polyol is glycerol.

[0117] Advantageously, the amount of water-soluble polyols in the creping adhesive composition is between 1 and 25% by weight relative to the total weight of the creping adhesive composition, preferably between 2 and 20% by weight, more preferably between 3 and 10% by weight.

[0118] Examples of Yankee protective agents against salts include monoammonium or diammonium phosphate.

[0119] Advantageously, the quantity of Yankee salt-protecting agents in the creping adhesive composition is between 1 and 20% by weight relative to the total weight of the creping adhesive composition, preferably between 2 and 15% by weight, more preferably between 3 and 10% by weight.

[0120] Advantageously, the pH of the creping adhesive composition is adjusted between 7 and 8.

[0121] The creping adhesive composition according to the invention is advantageously diluted with water before use, advantageously at a water / adhesive composition ratio of between 1:10 and 10:1.

[0122] The present invention also relates to a method for manufacturing tissue paper comprising the use of the creping adhesive composition according to the invention.

[0123] The process for manufacturing tissue paper includes the following steps: i) preparation of a paper pulp comprising at least virgin and / or recycled fibers; ii) dilution of the paper pulp to form a fiber suspension; iii) formation of a sheet of paper from the fibre suspension using pressure rollers; (iv) drying the sheet of paper on a Yankee cylinder to obtain a dried sheet of paper; v) formation of a sheet of tissue paper by creping the dried sheet of paper using a creping blade.

[0124] The creping adhesive composition according to the invention is applied upstream of the drying of the paper sheet, i.e. between steps iii) and iv).

[0125] The application of the creping adhesive composition can be done by continuous spraying onto the Yankee.

[0126] In a particular mode, the creping adhesive composition is sprayed between 0.5 g / m2 and 100 g / m2, preferably between 1 g / m2 and 50 g / m2, more preferably between 2 g / m2 and 30 g / m2, even more preferably between 5 g / m2 and 20 g / m2 (active material P1+P2).

[0127] The present invention will be described in more detail with reference to the following examples, which merely illustrate the invention and are not limiting. EXAMPLES

[0128] List of polymers used - The counter-example polymer CE Pl-1 corresponds to a polyvinylamine obtained by hydrolysis of a PB2 base polymer of polyvinylformamide (degree of hydrolysis of 50%), CE Pl-1 having a molecular weight of 40,000 g / mol. - The P1-2 polymer corresponds to a polyvinylamine obtained by hydrolysis of a PB2 base polymer of polyvinylformamide (degree of hydrolysis of 50%), Pl-2 having a molecular weight of 50,000 g / mol. - The P1-3 polymer corresponds to a polyvinylamine obtained by hydrolysis of a PB2 base polymer of polyvinylformamide (degree of hydrolysis of 50%), Pl-3 having a molecular weight of 150,000 g / mol. - The P1-4 polymer corresponds to a polyvinylamine obtained by hydrolysis of a PB2 base polymer of polyvinylformamide (degree of hydrolysis of 50%), Pl-4 having a molecular weight of 950,000 g / mol. - The counter-example polymer P1-5 corresponds to a polyvinylamine obtained by hydrolysis of a PB2 base polymer of polyvinylformamide (degree of hydrolysis of 50%), Pl-5 having a molecular weight of 1,000,000 g / mol. - The counter-example polymer CE P2-1 corresponds to a polyethyleneimine obtained by reaction of ethylene dichloride with ammonia, CE P2-1 having a molecular weight of 1000 g / mol. - The P2-2 polymer corresponds to a polyethyleneimine obtained by reaction of ethylene dichloride with ammonia, P2-2 having a molecular weight of 10,000 g / mol. - The P2-3 polymer corresponds to a polyethyleneimine obtained by reaction of ethylene dichloride with ammonia, P2-3 having a molecular weight of 20,000 g / mol. - The P2-4 polymer corresponds to a polyethyleneimine obtained by reaction of ethylene dichloride with ammonia, P2-4 having a molecular weight of 500,000 g / mol. - The counter-example polymer CE P2-5 corresponds to a polyethyleneimine obtained by reaction of ethylene dichloride with ammonia, CE P2-5 having a molecular weight of 550,000 g / mol.

[0129] Obtaining creping adhesive compositions Adhesive composition Cl In a beaker, while stirring, 45 g of a 14% wt. solution of Polymer Pl-2 are mixed with 30 g of a 30% wt. solution of Polymer P2-2. Water and formic acid are added to form 100 g of adhesive composition Cl with a pH between 7 and 8. The same experimental protocol is carried out by modifying the added polymers, and possibly the quantities of water and formic acid to obtain 100 g of C2 to C15 adhesive compositions with a pH between 7 and 8, the compositions are summarized in Table 1. In addition, 5 g of glycerol is added to the C2 adhesive composition.

[0130] [Tables 1] CempositioB adhesive creping Polymer 1 (g) Polymer 2 (g) Olyçsralfg) CI (INV) PI-2 (63) P2-2 19 î C2 ONV) Pl-2 (63) P2-2 (9) 5 C3 (CE) Pl-2 (153) - - C4 (CE) - p 2-2 (153) - C5 (INV) Pl-2 (63) P2-4 (9) - C6 (INV) P1-4 (6 UP 2-2 (9) - C7 (INV) P1-3 (63) P2-3 (9) - C8 (INV) P1-4 (63) P2-4 (9) - C9 (CE) CE P1 -1 (63) P2-2 (9) - CIO (CE) CEP1-1 (63) P2-4 (9) - CU (CE) Pl-2 (63) CE P2-1 (9) - C12 (CE) Pl-2 (63) CE P2-5 (9) - C13 (CE) P1-4 (63) CE P 2 1 (9) - 04 (CE) PI -4 (63) CE P2-5 (9) - C15 (CE) CEP1-5 (63) P2-2 (9) - C16 (CE) CE PI -5 (63) P2-4 (9) - Flexibility Tests

[0131] Coatings that are too hard often result in poor crepe blade durability and chafing, leading to defects on tissue paper and sometimes chafing marks on the Yankee cylinder. Therefore, the dried adhesive must be flexible to protect the Yankee cylinder and improve the crepe blade's lifespan.

[0132] Protocol In a 150 mL beaker, 5 mL of water and 5 mL of crepe adhesive are mixed. The mixture is pipetted onto a 15 cm diameter, 2.5 cm thick aluminum plate. The plate is then heated for 2 hours at 105 °C. The flexibility of the adhesive is rated from 1 to 10 (1 being the lowest and 10 the highest) by bending the aluminum plate, according to the following scale: 1-2: The adhesive peels off completely or partially from the aluminum plate; 3-4: The adhesive does not peel off but many cracks are observed corresponding to the cracking of the adhesive layer; 5-6: Some cracks are observed; 7-9: No cracks are observed, but resistance to bending is felt when bending the aluminum plate; 10: The plate bends in the same way as if there were no adhesive. The results are summarized in Table 2. An acceptable flexibility value starts at 7.

[0133] [Tables2] Adhesive creping composition Cl (IN V) C2 (IN V) C3 (CE ) C4 (CE ) C5 (IN V) C6 (IN V) C7 (IN Al CS (IN Al C9 (CE ) CIO (CE ) en (CE Cl 2 (CE ) Cl 3 (CE ) C14 (CE ) Cl 5 (CE CI 6(CE) Flexibility value 9 4 S 10 9 £ 6 g 5 9 4 g 7 6 Adhesion tests

[0134] The primary objective of Yankee adhesive is to ensure adhesion between the creping cylinder and the fiber tape. However, this adhesion must not be too high to avoid paper defects and insufficient stretching.

[0135] Protocol On a steel plate (Q-Lab A-Panel RS14; 2.5 cm * 10 cm) heated to 150 °C for 5 seconds, 9.18 g / m2 of previously prepared adhesive compositions is sprayed using a Paasche V5 spray, at a pressure of one bar. The steel plate is left to cool until it reaches room temperature. The highly absorbent paper towel strip is soaked in water, then pressed under two sheets of blotting paper with a 2 kg roller, making one pass back and forth, before being placed on the steel plate. Another sheet of blotting paper is then placed on top of the strip and pressed again with a 2 kg roller, making two passes back and forth. Finally, the plate is placed in an oven for 5 minutes at 95°C.

[0136] The adhesion force at 180 °C of the strip on the plate is measured using a peel-off program on Testometric AX, and the values ​​are summarized in Table 3. In the adhesion test, the most appropriate adhesion force is between 0.2 and 0.6 N (i.e., rated 2 or 3 on a scale of 1 to 10).

[0137] [Tables3] Creasing adhesive composition Cl (IN V) C2 (IN Al C3 (CE ) C4 (CE C5 (IN Al C6 (IN Al (IN V) CS (IN Al C9 (CE ) C10 (CE C11 (CE C12 (CE C13 (CE ) C14 (CE ) C15 (CE Cl 6 (CE) Adhesion strength (N) 0.48 0.29 0.40 2.12 P 0.28 0.27 9.42 0.84 2.16 1.74 2.84 0.3 8 1.10 0.21 1.51 Adhesion value 3 7 3 8 3 2 2 1 4 8 7 9 3 N 7 6 Water absorption and dissolution tests

[0138] High water absorption and low dissolution are important characteristics of a Yankee adhesive. High water absorption helps the wet fiber tape penetrate the Yankee coating, while preventing the Yankee coating from hardening. Low dissolution is necessary to prevent the adhesive from migrating into the wet fiber tape, which can lead to a reduction in the surface protection of the Yankee.

[0139] Protocol The previously prepared creping adhesive composition (10 g) is gradually poured onto a 15 cm diameter aluminum plate, then dried for 4 hours at 105 °C. The plate is then left to cool to room temperature, then weighed before being immersed in a container containing 3 L of water for 150 seconds, under sufficient agitation to form a slight vortex. The plate is then drained and weighed again to measure the water absorbed. The plate is then dried for 2 hours at 105 °C and weighed again, after cooling to room temperature, to measure the amount of creping adhesive composition that has dissolved. The results are summarized in Table 4. An acceptable absorption value is classified above 7 on a scale of 1 to 10. An acceptable dissolution value is classified above 7 on a scale of 1 to 10.

[0140] [Tables4] Creasing adhesive composition % of water absorbed Absorption value % of adhesive composition dissolved Dissolution value Cl (INV) 123.4 8 8.4 9 C2 (INV) 124.2 8 14.4 S C3 (CE) 93.2 6 47.2 6 C4 (CE) 70.1 5 77.1 Q C5 (INV) 112.3 “J 17.6 8 C6 (INV) 125.4 8 4.1 10 C7 (INV) 138.9 10 7.9 9 CS (INV) 121.7 S 8.2 9 C9 (CE) 44.2 -s 48.8 6 CI G (CE) 90.1 6 58.1 4 Cil (CE) 52.1 4 29.3 / C12 (EC) gg.4 6 67.9 3 CI 3 (EC) 89.6 6 28.3 CI 4 (EC) 122.2 8 47.8 6 CI 5 (EC) 109.3 7 13.9 8 CI6 (EC) 123.9 8 51.1 6

[0141] All the characteristics of the different tests carried out are summarized in Table 5.

[0142] [Tables5] Creasing adhesive composition Flexibility value Adhesion value Absorption value Dissolution value Cl (INV) ■7 3 S 9 €2 (INV) 9 '7 £ 8 C3 (CE) 4 3 6 6 C4 (CE) 5 8 5 7 C5 (INV) 1Û '4 ■7 8 C6 (INV) T 8 10 CT (INV) 9 2. 10 9 CS (INV) 8 4 8 9 C9 (CE) 6 4 3 6 CIO (CE) 8 8 6 4 Cil (CE) 5 4 '7 C12 (CE) 9 9 6 3 Cl 3 (CE) 4 6 -T? C14 (CE) 8 N 8 6 Cl5 (CE) 2 2 S C16 (CE) 6 6 8 6

[0143] Only the adhesive compositions according to the invention (Cl, C2, C5, C6, C7 and C8) offer satisfactory properties in terms of flexibility, adhesion, water absorption and dissolution in water.

Claims

Demands

1. Creasing adhesive composition comprising: A / at least one polymer PI and at least one polymer P2; said at least one polymer PI and at least one polymer P2 representing between 10 and 60% by weight of the adhesive composition; and B / at least one hydrophilic solvent representing between 40 and 90% by weight of the adhesive composition; i) the polymer PI, having a molecular weight of between 50,000 and 950,000 g / mol, selected from the group consisting of: * polyamines obtained by Hofmann rearrangement on a PB1 base polymer of at least one monomer selected from the group consisting of acrylamide, methacrylamide and mixtures thereof; * polyamines resulting from the hydrolysis of the amide -N(R2)-CO-R' groups of a PB2 base polymer of at least one monomer of formula (I): [Chem.l] R2 Qf P; ~~~~ f'' il --- N CO— (O in which: R1 and R2 are, independently, a hydrogen atom or an alkyl chain having from 1 to 6 carbon atoms, and * mixtures thereof; ii) the polymer P2, having a molecular weight between 1,500 and 500,000 g / mol, chosen from the group consisting of: * polyethyleneimines obtained by polycondensation of ethylene dichloride with ammonia, * polyethyleneimines obtained by polycondensation of aziridine, and * mixtures thereof.

2. Creasing adhesive composition according to claim 1, characterized in that the PI polymer is a polyamine resulting of the hydrolysis of the amide groups -N(R2)-CO-R' of a PB2 base polymer of a monomer of formula (I): [Chem.l] R* — N CO— (i) in which: R1 and R2 are, independently, a hydrogen atom or an alkyl chain having from 1 to 6 carbon atoms.

3. Creping adhesive composition according to claim 2, characterized in that the PI polymer is a polyamine having a degree of hydrolysis between 1 and 100 mol%.

4. Creping adhesive composition according to any one of the preceding claims, characterized in that the PI polymer comprises at least one monomer having a quaternary amine function.

5. Creping adhesive composition according to claim 4, characterized in that the monomer having a quaternary amine function is diallyl dimethyl ammonium chloride.

6. Creping adhesive composition according to any one of claims 4 or 5, characterized in that the monomer having a quaternary amine function is present in an amount of at least 25 mol% and at most 50 mol%.

7. Creping adhesive composition according to any one of the preceding claims, characterized in that the P2 polymer is obtained by polycondensation of ethylene dichloride with ammonia.

8. Creping adhesive composition according to any one of the preceding claims, characterized in that the polymer P2 comprises between 0.0001 and 1 mol% of at least one branching agent, relative to the amount of amines present in the polymer P2.

9. Creping adhesive composition according to any one of the preceding claims, characterized in that the P2 polymer comprises a branching agent selected from polyethylene glycol diglycidic ether, 1,4-butanediol diglycidic ether, ethylene glycol diglycidic ether.

10. Creping adhesive composition according to any one of the preceding claims, characterized in that the creping adhesive composition has a weight ratio between polymer PI and P2 of between 5:95 and 95:

5.

11. A method for manufacturing tissue paper comprising the use of a creping adhesive composition according to any one of claims 1 to 10.