EP1002033B1 - Low viscosity dispersion for paper or textile processing - Google Patents

Description

The present invention relates to concentrated, low-viscosity aqueous dispersions for the treatment of paper and textiles, a production process for this dispersion and the use of the dispersion for softening paper and textiles.

Softness plays an important role in many paper and textile technology products. The consumer expects that textiles or paper products, such as paper handkerchiefs, household tissues or hygiene articles, feel as soft as possible. A large number of suitable compounds and compositions are therefore already known for softening paper and textiles. From US 3,594,224 it is known that certain quaternary ammonium compounds are suitable. to improve the softness of cellulose fibers. WO 96/08601 proposes a polysiloxane-containing treatment agent for tissue products. wherein the agent contains a polyhydroxy compound such as polyethylene glycol or glycerin in addition to polysiloxanes. WO 94/10381 describes mixtures of quaternary ammonium compounds and polyethylene glycol or polypropylene glycol for the softening of paper products and cellulose-containing fibers. EP 569 847 A1 describes alkoxylated natural oils and fats as active ingredient components for fabric softener formulations. EP 494 769 A2 describes textile plasticizers based on pentaerythritol esters. EP 698 140 B1 claims tissue paper. which is treated with a tricomponent plasticizer. Sorbitan fatty acid esters are used as the softening component. These compounds are formulated in the form of aqueous dispersions and applied to the products in a suitable manner. EP 698 140 B1 proposes a suitable emulsifier system nonionic emulsifiers, such as alkyl (oligo) glycosides or ethoxylated or propoxylated sorbitan esters in combination with selected polyhydroxy compounds. EP 691 396 describes plasticizer concentrates which, in combination with 0.1 to 25% by weight of an ester of a C _1-22 carboxylic acid with mono- or polyhydric alcohols and polyols, contain 5-40% by weight of cationic plasticizer.

However, these agents often only contain up to 10% by weight of active substances, since more highly concentrated dispersions can also have a significantly increased viscosity, which means direct processing. e.g. by spraying onto the textile or paper web, makes it difficult or impossible. Such highly concentrated dispersions also tend to separate or break more quickly and have a reduced storage stability.

It was therefore the object of the present invention. to provide concentrated but low-viscosity agents in the form of aqueous dispersions for the softening treatment of paper and textiles.

It has been found that dispersions. which contain a selected combination of plasticizers based on glycerin and its derivatives. meet the above requirements for low viscosity and high stability.

• a) eine nichtionische Weichmacherkomponente die aus Mono- oder Diestern des Glycerins mit C_8-22-Fettsäuren und Mischungen hiervon ausgewählt ist.
• b) eine Polyolverbindung
• c) kationische und nichtionische Emulgatoren
• d) 70 bis 90 Gew.-% Wasser

und gegebenenfalls weiteren Hilfs- und Zusatzstoffen, wobei das Gewichtsverhältnis der Komponenten a) und b) zwischen 2.5 : 1 und 1 : 2.5 beträgt und die kationischen Emulgatoren in Mengen zwischen 0,5 und 3,0 Gew.% enthalten sind.The present application therefore relates to concentrated, low-viscosity, aqueous dispersions for the finishing of paper and textiles which contain

• a) a nonionic plasticizer _component which is selected from mono- or diesters of glycerol with C _8-22 fatty acids and mixtures thereof.
• b) a polyol compound
• c) cationic and nonionic emulsifiers
• d) 70 to 90 wt .-% water

and optionally further auxiliaries and additives, the weight ratio of components a) and b) being between 2.5: 1 and 1: 2.5 and the cationic emulsifiers being present in amounts between 0.5 and 3.0% by weight.

The dispersions according to the invention are of low viscosity, ie they preferably have a Brookfield viscosity, measured at 20 ° C. with a spindle of 1 and 20 rpm, between 1 and 100 mPa s and in particular between 1 and 50 mPa s. Dispersions whose viscosity is below 10 mPas are particularly preferred. The water content is between 70 and 90% by weight, dispersions with less than 80% by weight water being preferred. The dispersions are finely divided and stable in storage and can be applied directly to the paper or textiles. Additional dilution or other conditioning is not necessary.

The dispersions are generally suitable for the softening treatment of paper or textiles. They can be used for permanent equipment as well as for temporary equipment. So it is possible. to use the dispersions in the manufacture or refinement of paper products or textiles or as post-treatment or fabric softener in machine or industrial laundry or as tumble aids.

In the context of the present application, textiles are understood to mean all textile piece goods. the synthetic or natural fibers. eg wool, cotton. Contain polyamide polyester or polyacrylic fibers or mixtures of these fibers. However, the textile fibers themselves can also be treated with the dispersions.
In addition to paper and paper products, cellulose-containing fibers, for example cell and wood pulp fibers and nonwovens made from these fibers, can also be treated with the dispersions. The use of the dispersions for the softening of paper or paper products is preferred. This includes, for example, tissue paper. which is used in the manufacture of handkerchiefs, kitchen and household towels. as well as hygiene items such as tampons. Toilet paper and diapers are used.

All methods known to those skilled in the art for applying liquid treatment agents can be used in the treatment of paper or textiles. eg by printing, spraying. Splashing, padding. Size presses, air nozzles, squeegees, rollers or engraving. As a rule, textile or paper webs are brought into contact with the dispersions in suitable machines and the dispersion is applied to the textile material or paper in suitable amounts. In the treatment of textile goods, pulling-on processes are also possible, in which the textile goods remain in the aqueous dispersion and the active substances are pulled onto the fibers. The dispersions can if necessary also in hot condition. ie used at temperatures up to 80 ° C.

Such methods are described for paper finishing, for example in the Handbook of Paperboard and Board, RRA Higham, BB Ltd., London 1970, pages 142 to 169 or for textile technology in finishing of textiles, VEB Fachbuchverlag Leipzig 1990, pages 193 to 228 .

The dispersions contain mono- or diesters of glycerol with C _8-22 fatty acids as nonionic softening component a). where the C _8-22 fatty acids can be linear or branched, saturated or unsaturated. Glycerol esters based on saturated, linear fatty acids, such as lauric acid, are particularly suitable. Myristin, palmitin, stearin. Arachinic or behenic acid or mixtures of these acids. The mono- or diglycerides can also be used in the form of mixtures as they arise due to the technical production process. The glycerides can also be contained in any mixtures of mono- and diglycerides. However, dispersions which, based on the plasticizer component a), contain at least 60% by weight of diglycerides are preferred. The dispersions preferably contain the nonionic plasticizer component a) in amounts of between 1 and 14% by weight. such dispersions are preferred. which contain the plasticizer in amounts between 5 and 10 wt .-%.

As a further essential ingredient, the dispersions contain at least one polyol compound b) in amounts such that the weight ratio between the nonionic plasticizer component and the polyol compound is in the range from 2.5: 1 to 1: 2.5 and preferably in the range from 2.0: 1 to 1: 1. Polyol compound is understood to mean organic compounds with at least two carbon atoms and at least two hydroxyl groups in the molecule, the hydroxyl group not being derivatized. Suitable poly compounds are, for example, glycerol and its dimers or trimers. Glycols and their polymers, pentaerythritol, di- and trimethylolpropane, sorbitan, manitol, xylitol, glucose, mannose or fructose.

The dispersions preferably contain glycerol, diethylene glycol, polyethylene glycol or 1,2-propylene glycol and mixtures thereof as the polyol compound. Also preferred are those dispersions which contain polyethylene glycol with an average molecular weight between 200 and 1000 and preferably between 200 and 600.

The proportion of polyol compounds b) is preferably in the range from 1.0 to 12.0% by weight and in particular in the range from 5 to 10% by weight. Mixtures of glycerol with polyethylene glycol and in particular mixtures in which the weight ratio between glycerol and polyethylene glycol is between 10: 1 and 6: 1 are particularly suitable. The glycols are preferably present in amounts between 0.1 and 2.0% by weight and in particular between 0.1 and 1.0% by weight.

As emulsifiers c) for the nonionic plasticizers, the dispersions according to the invention contain a system of cationic and nonionic emulsifiers. Particularly suitable nonionic emulsifiers are fatty acids and fatty alcohols or their derivatives, in particular their reaction products with alkoxides such as ethylene oxide, propylene oxide and / or butylene oxide. Cationic emulsifiers are preferably compounds with at least one cationically charged nitrogen atom.

Suitable cationic emulsifiers are preferably selected from the group of the quaternary ammonium compounds of the formulas (I) and (II) where R is an acyclic alkyl radical having 12 to 24 carbon atoms, R ^{1 is} a saturated C ₁ -C ₄ alkyl or hydroxyalkyl radical, R ^{2 is} either R or R ¹ and COR ^{3 is} is an aliphatic acyl radical having 12 to 22 carbon atoms with 0, 1, 2 or 3 double bonds and R ⁴ is hydrogen or OH, where n is 1, 2 or 3 and X is either a halide, methosulfate, metophosphate or Is phosphate ion. as well as mixtures of these compounds. Compounds which contain alkyl radicals having 16 to 18 carbon atoms are particularly preferred.

Examples of cationic emulsifiers of the formula (I) are didecyldimethylammonium chloride, ditallow dimethylammonium chloride or dihexadecydimethylammonium chloride. Examples of compounds of the formula (II) are methyl-N, N-bis (acyloxyethyl) -N- (2-hydroxyethyl) ammonium methosulfate. Methyl-N- (2-hydroxyethyl) -N, N-di (tallow acyloxyethyl) ammonium methosulfate and bis (palmitoyl) ethyl hydroxyethyl methyl ammonium methosulfate or. In addition to the compounds of the formulas (I) and (II), it is also possible to use short-chain, water-soluble, quaternary ammonium compounds, such as, for example, trihydroxyethyl methyl ammonium methosulfate or cetyl trimethyl ammonium chloride. Also protonated alkylamine compounds. which have a softening effect. are suitable.
If quaternized compounds of formula (II) are used which have unsaturated alkyl chains. preference is given to the acly groups whose corresponding fatty acids have an iodine number between 5 and 25, preferably between 10 and 25 and in particular between 15 and 20 and which have a cis / trans isomer ratio (in% by weight) of 30:70. preferably greater than 50: 50 and in particular greater than 70: 30.

In addition to the quaternary compounds described above, other known compounds can also be used, such as quaternary imidazolinium compounds of the formula (III) where R ^{5 is} a saturated alkyl radical having 12 to 18 carbon atoms. R ^{6 represents} an alkyl radical with 1 to 4 carbon atoms or hydrogen and Z represents an NH group or oxygen and A is an anion.

Further suitable quaternary compounds are described by formula (IV) where R ⁷ is independently selected for a C _1-4 alkyl, alkenyl or hydroxyalkyl group. R ⁸ each independently represents a C _8-28 alkyl group and n is a number between 0 and 5. X stands for an anion, for example a halide. Methosulfate. Metophosphate or phosphate ion. The dispersions according to the invention contain the cationic emulsifiers in amounts between 0.5 and 3.0% by weight and in particular between 1.0 and 2.0% by weight.

The dispersions also contain nonionic emulsifiers, preferably from the group of the alkoxylated fatty acids with 8 to 22 C atoms, the alkoxylated fatty acid esters from fatty acids with 8 to 22 C atoms with monohydric alcohols with 1 to 10 C atoms and the alkoxylated fatty alcohols with 8 to 22 carbon atoms, the alkoxylated compounds having HLB values between 3 and 20 and preferably between 8 and have 16. The HLB value (hydrophilic-lipophilic balance) is a measure of the water or oil solubility of nonionic surfactants (cf. Römpp Chemie Lexikon, Volume 3, 9th edition 1990, page 1812-13). It is defined by the following equation: where SZ stands for the acid number and VZ for the saponification number of the corresponding compound.

The fatty acid ester alkoxylates are known compounds which are described, for example, in US 2,678,935, US 3,539,518, US 4,022,808 or GB 1,050,497 .

The alkoxylated fatty acid esters can be prepared by all methods known to the person skilled in the art, for example by esterifying fatty acids with alkoxylated methanol, as described, for example, in US Pat . No. 3,539,518 . Another possibility is the direct reaction of fatty acid esters with alkylene oxides in the presence of transition metal catalysts, as described in US Pat . No. 4,022,808 . However, the fatty acid alkyl ester alkoxylates are preferably prepared by heterogeneously catalyzed direct alkoxylation of fatty acid alkyl esters with ethylene oxide and / or propylene oxide on hydrophobicized hydrotalcites. This synthesis method is described in detail in the laid-open publications WO 90/13533 and WO 91/15441 . The resulting products are characterized by a low OH number. the reaction is carried out in one step and light-colored products are obtained. The fatty acid alkyl esters used as starting materials can be obtained from natural oils and fats as well as produced synthetically.

Examples of particularly suitable nonionic emulsifiers are C _12-18 fatty alcohols with 7 to 14 moles of ethylene oxide per mole of alcohol or cetyl / stearyl alcohol with 20 moles Ethylene oxide and C _12-18 fatty acids or fatty acid esters with C _1-4 alcohols, which contain between 8 and 16 moles of ethylene oxide per mole of fatty acid or ester.

Further suitable nonionic emulsifiers are selected from the group of the alkyl (oligo) glycosides of the formula RO- [Z] _x in which R is an alkyl radical having 8 to 22 carbon atoms, Z is a sugar radical having 5 or 6 carbon atoms and x stands for a number between 1 and 10. Alkyl (oligo) glycosides, their preparation and use as surface-active substances are known, for example, from DE 19 43 689 A1 or from DE 38 27 543 A1 .

Regarding the glycoside residue applies. that both monoglycosides. in which a sugar residue is glycosidically bound to the fatty alcohol, and oligomeric glycosides with an average degree of oligomerization of up to about 2 are particularly suitable. The glycoside residue contained in the commercially available alkyl oligoglycosides is the glucoside residue.

The proportion of nonionic emulsifiers is preferably between 0.1 and 3.0% by weight and in particular between 0.5 and 1.5% by weight.

The dispersions contain, as solvent d), water in amounts between 70 and 90% by weight. Desalinated water is preferably used. Tap water can also be used. The pH of the dispersions is preferably in the range from 4.5 to 7.5 and in particular in the range between 5.0 and 6.5 and can be achieved by adding suitable acids. e.g. HCl or bases, such as aqueous sodium hydroxide solution, are adjusted.

In addition to the ingredients a) to d) described, the dispersions according to the invention may also contain other auxiliaries and additives customary in paper or textile technology. These include, for example, biocides. Preservatives, dyes, pearlescent agents, defoamers. Soil-release compounds, UV absorbers, perfume oils or fragrances and other additives obtained from native sources, such as vitamins or plant extracts.

The dispersions described can be prepared in any manner known to those skilled in the art. However, it is preferred to add the nonionic plasticizer and the cationic emulsifier together to a mixture of the remaining components (nonionic emulsifier. Glycerol and water and, if appropriate, auxiliaries and additives), which may be necessary depending on the melting points of the individual components to heat the mixtures, usually to temperatures between 40 and 80 ° C. The raw dispersion is then mixed intensively.

The dispersions are finely divided and contain at least 90% (number distribution) particles. which are smaller than 1000 nm. preferably smaller than 500 nm. Therefore only such homogenizers can be used. which transmit sufficiently large shear forces. to obtain the desired finely divided dispersions. Suitable devices are, for example, high-pressure or ultrasonic homogenizers.

It has been shown that the use of certain homogenizers leads to dispersions with particularly advantageous properties.
Another object of the present application therefore relates to a method for producing the dispersions described above. components a) to c) and any auxiliary substances which may be present are first dispersed in water and this crude dispersion is then mixed with a high-pressure homogenizer known to the person skilled in the art, such as that from APV Homogenizator GmbH. Lübeck, is produced, is homogenized at pressures between 10 and 600 bar. In this case, it is particularly preferred to carry out the homogenization at pressures between 25 and 250 bar.
As usual when using high pressure homogenizers. the raw dispersion is first at low pressures, ie in the range from 10 to 50 bar and then at higher pressures, above 50 bar. homogenized. It may be advantageous to homogenize the dispersions several times at different pressures. It is further preferred to carry out the homogenization at temperatures between 20 and 100 ° C., preferably between 25 and 70 ° C. Depending on the auxiliary and Additives may therefore also be preferred. add these to the dispersions only after homogenization.

Examples

Three different dispersions were made. by first melting the nonionic plasticizer with the cationic emulsifier at 70 ° C. This melt was then added to the remaining components, which were placed in a stirred kettle at 70 ° C., and stirred for 15 minutes. The crude dispersion obtained in this way was cooled to room temperature and then homogenized at 40 ° C. using a high-pressure homogenizer from APV Homogenizator GmbH, Luebeck, model LAB 60/60 once at 50 bar and twice at 200 bar. The pH of the dispersion was 5.5.
Only the dispersion 1 according to the invention has the desired low viscosity, while the comparative dispersions 2 and 3 showed a viscosity that can no longer be determined.
The composition of concentrates 1 to 3 is shown in Table 1:

Claims (14)

1. A concentrated low-viscosity aqueous dispersion for the softening of textiles and paper containing

   a) a nonionic softener component selected from monoesters or diesters of glycerol with C_8-22 fatty acids and mixtures thereof,

   b) a polyol compound,

   c) cationic and nonionic emulsifiers,

   d) 70 to 90% by weight water and optionally other auxiliaries and additives, the ratio by weight of component a) to component b) being from 2.5:1 to 1:2.5,

   characterized in that cationic emulsifiers are present in quantities of 0.5 to 3.0% by weight.
2. A dispersion as claimed in claim 1, characterized in that it has a Brookfield viscosity, as measured at 20°C (spindle 1, 20 r.p.m.), in the range from 1 to 100 mPa·s and preferably in the range from 1 to 50 mPa·s.
3. A dispersion as claimed in claim 1 or 2, characterized in that the polyol compound is selected from glycerol, diethylene glycol, polyethylene glycol and 1,2-propylene glycol or mixtures thereof.
4. A dispersion as claimed in any of claims 1 to 3, characterized in that the cationic emulsifiers used are quaternary ammonium compounds corresponding to formulae (I) and (II): in which R is an acyclic alkyl group containing 12 to 24 carbon atoms, R¹ is a saturated C_1-4 alkyl or hydroxyalkyl group, R² has the same meaning as R or R¹ and COR³ stands for an aliphatic acyl group containing 12 to 22 carbon atoms and 0, 1, 2 or 3 double bonds and R⁴ is hydrogen, or OH, n has a value of 1, 2 or 3 and X is a halide, methosulfate, methophosphate or phosphate ion.
5. A dispersion as claimed in any of claims 1 to 4, characterized in that the nonionic emulsifiers present are alkoxylated fatty acids containing 8 to 22 carbon atoms, alkoxylated fatty acid esters of fatty acids containing 8 to 22 carbon atoms with alcohols containing 1 to 10 carbon atoms and/or alkoxylated fatty alcohols containing 8 to 22 carbon atoms, the alkoxylated compounds having HLB values of 3 to 20.
6. A dispersion as claimed in any of claims 1 to 5, characterized in that the nonionic softener component a) is present in quantities of 1 to 14% by weight and preferably in quantities of 5 to 10% by weight.
7. A dispersion as claimed in any of claims 1 to 6, characterized in that the nonionic emulsifier is present in quantities of 0.1 to 3.0% by weight.
8. A dispersion as claimed in any of claims 1 to 7, characterized in that a mixture of glycerol and polyethylene glycol is present as component b).
9. A dispersion as claimed in claim 8, characterized in that the ratio by weight of glycerol to polyethylene glycol is between 10:1 and 6:1.
10. A process for the production of the dispersions claimed in claim 1, characterized in that components a) to c) and the auxiliaries present, if any, are dispersed in water and the crude dispersion obtained is subsequently homogenized under pressures of 10 to 600 bar in a high-pressure homogenizer.
11. A process as claimed in claim 10, characterized in that the crude dispersion is homogenized under pressures of 25 to 250 bar.
12. The use of the dispersions claimed in claim 1 for the softening of paper.
13. The use of the dispersions claimed in claim 1 for the softening of textile piece goods.
14. The use of the dispersions claimed in claim 1 as fabric softeners.