DE19512399A1 - Paper sizing mixtures - Google Patents

Abstract

Paper sizing agent mixtures of: (A) finely divided aqueous dispersions of C14 to C22 alkyl diketenes obtainable by dispersing the alkyl diketenes in water in the presence of cationic starch with an amylopectin content of at least 95 wt.%, and (B) finely divided aqueous polymer dispersions forming a paper sizing agent, process for producing the paper sizing agent mixtures by mixing th e components (A) and (B) and the use of the paper sizing agent mixtures as mass and surface sizing agents for paper, pasteboard and cardboard.

Description

The invention relates to paper sizing mixtures

• (A) finely divided, aqueous dispersions of C₁₄ to C₂₂ alkyldi ketenes by dispersing the alkyldiketenes in water are available in the presence of cationic starch and
• (B) polymer dispersions that are a sizing agent for paper,

Process for the production of the named paper sizes mixtures by mixing components (A) and (B) or by Emulsifying C₁₄ to C₂₂ alkyl diketenes in a mixture aqueous suspensions of cationic starches and finely divided, aqueous polymer dispersions containing a sizing agent for paper are, at temperatures of at least 70 ° C and using the Pa sizing mixtures as mass and surface sizing medium for paper, cardboard and cardboard.

The above-mentioned paper sizing mixtures as well as their Production and use are known from WO-A 94/05855.

The aqueous dispersions indicated under (A) and (B) belong the state of the art. For example, from the US-A-3 130 118 aqueous alkyl diketene dispersions known by dispersing the alkyldiketenes in water in the presence of cationic starch are available. Fatty alkyl diketene Dispersions in the presence of cationic condensates and where appropriate, cationic starch are produced at for example from DE-A-30 00 502 and DE-A-33 16 179 be knows. Stabilized aqueous alkyldi are known from EP-B-0 437 764 ketene dispersions known to contain up to 40 wt .-% alkyl diketene can contain dispersed and as a stabilizer in addition to cat ionic starch long chain fatty acid esters and / or urethanes contain.

Aqueous polymer dispersions that are a sizing agent for paper are, for example, in the following references wrote: JP-A-58/115 196, EP-B-0 257 412, EP-B-0 267 770, EP-B-0 051 144, EP-A-0 058 313 and EP-A-0 150 003. These References are given in WO-A-94/05855 mentioned above riert.  

From DE-A-32 35 529 paper sizing mixtures are be knows from emulsions of C₁₄ to C₂₀ alkyldiketenes and polymerized finely divided, nitrogen-containing monomers ent holding polymer dispersions consist of the above EP-B-0 051 144 are known. These sizing mixes who by combining a fatty alkyl diketene emulsion with a aqueous, finely divided polymer dispersion produced or only in Formed paper stock before sheet formation by that emulsified fatty alkyl diketene and the finely divided aqueous disper addition to the paper stock and the system well mixed up. Mixtures that are only added by stirring cat Ionic fine-particle aqueous polymer dispersions in fatty alkyl diketene dispersions are not sufficient stable in storage.

From EP-B-0 353 212 sizing agents are in the form of aqueous Emulsions known to have a hydrophobic cellulose-reactive lei means, e.g. B. fatty alkyl diketene, and a cationic starch with an amylopectin content of at least 85% and a catio Degree of degree (D.S.) from 0.045 to 0.40 included. The share of Amylopectin in the cationic starch is preferably 98 until 100%. Starch which is preferably used is waxy corn starch.

EP-B-0 369 328 discloses aqueous alkyl diketene dispersions knows that contain up to 30 wt .-% ketene dimer. Eat more Partial components of these alkyldiketene dispersions are cat ionic starch, preferably cationic waxy maize starches, Aluminum sulfate, carboxylic acids with 1 to 10 carbon atoms, and Sulfonates such as lignin sulfonic acid or condensation products from Formaldehyde and naphthalene sulfonic acids.

The present invention has for its object a ver improved paper sizing agent containing fatty alkyl dike to provide that when used as a mass sizing agent results in sufficient instant sizing and that does not affect the whiteness of the paper and an improved shear and compared to the known mixtures Has storage stability.

The object is achieved with paper sizing agents mixtures

• (A) finely divided, aqueous dispersions of C₁₄ to C₂₂ alkyldi ketenes by dispersing the alkyldiketenes in water Are available in the presence of cationic starch and  
• (B) finely divided, aqueous polymer dispersions containing a sizing are medium for paper,

if the amylopectin content of the cationic starch of the compo nente (A) is at least 95%. The amylopectin content of the cat Ionic strength is preferably 98 to 100%. Suitable Starches of this type are preferably cationic waxy maize starch ken.

The invention also relates to a method of manufacture development of paper sizing mixtures by mixing

• (A) finely divided, aqueous dispersions of C₁₄ to C₂₂ alkyldi ketenes by dispersing the alkyldiketenes in water are available in the presence of cationic starch with
• (B) finely divided, aqueous polymer dispersions containing a sizing are medium for paper,

or by emulsifying C₁₄ to C₂₂ alkyl diketenes in one Mixture of aqueous suspensions of cationic starches from finely divided, aqueous polymer dispersions containing a sizing agent are for paper at temperatures of at least 70 ° C. The The process is characterized in that the amylopectin content the cationic strengths is at least 95%.

The invention also relates to the use of the above be wrote paper sizing mixtures as mass and top surface sizing agent for paper, cardboard and cardboard.

For the production of component (A) one goes from C₁₄ to C₂₂-alkyldiketenes or mixtures of such alkyldiketenes. Alkyldiketenes are known and commercially available. you will be for example from the corresponding carboxylic acid chlorides Elimination of hydrogen chloride with tertiary amines. Suitable fatty alkyl diketenes are, for example, tetradecyl dike ten, hexadecyldiketene, octadecyldiketene, alkosyldiketene, docosyl diketen, palmityldiketen, stearyldiketen and behenyldiketen. Ge diketenes with different alkyl groups are also suitable, e.g. B. stearylpalmithyldiketene, behenylstearyldiketene, behenyl oleyldiketene or palmithylbehenyldiketene. Preferably used stearyldiketene, palmithtyldiketene, behenyldiketene or Mixtures of stearyl diketene and palmithyl diketene or Mixtures of behenyldiketene and stearyldiketene. The Diketen are in concentrations of 5 to 60, preferably 10 to Contain 40% by weight in the aqueous emulsions.  

The alkyldiketenes become more cationic in water in the presence of Starch emulsifies, which according to the invention have an amylopectin content of has at least 95, preferably 98 to 100%. Such strengths ken can, for example, by fractionating common na strengths or through breeding measures from such plants are obtained, which produce practically pure amylopectin starch ren, cf. Günther Tegge, Starch and Starch Derivatives, Hamburg, Bers-Verlag 1984, pages 157 to 160. Cationic strengths with an amylopectin content of at least 95, preferably 98 to 100% by weight are available on the market. The amylopectin strength have a branched structure and have a high polymer degree of risk. The molecular weights (number average) are at for example 200 million to 400 million. For waxy corn starch with an amylopectin content of 99 to 100% are in the Literature average molecular weights (number average) of about Stated 320 million. According to the invention, cationized Starches used, the amylopectin content be at least 95% wearing. The degree of cationization of the starch is determined with the help of the sub degrees of stitution (D.S.) specified. This value gives the number the cationic groups per monosaccharide unit in the cat ionic strength again. The degree of substitution (D.S. value) of the cationic starches is, for example, 0.010 to 0.150. In in most cases it is below 0.045, e.g. B. have the possible cationic starches preferably one Degree of substitution (D.S.) from 0.020 to 0.040.

The cationization of the at least 95% by weight of amylopectin contains Tending strength comes through the introduction of groups that are tertiary or contain quaternary nitrogen atoms, e.g. B. by implementation the starches in question, in particular waxy corn starch, with dialkylaminoalkyl epoxides of the formula

or with dialkylaminoalkyl chlorides of the formula

or preferably with quaternary ammonium containing epoxide groups salt the formula

or the corresponding halohydrins of the formula

In the formulas I to IV, the substituents R², R³ and R⁴ are Alkyl, aryl, aralkyl or hydrogen, R¹ represents an alkylene group, e.g. B. C₁-C₆ alkylene. Examples of such connections are 3-chloro-2-hydroxypropyltrimethylammonium chloride or glycidyltri methylammonium chloride.

In addition to the preferred preferred waxy maize starch wax potato starch, wax wheat starch or mixtures the mentioned strengths in cationized form.

The cationic starches with amylopectin levels of at least 95% are 0.5 to 5, preferably 1 to 3 wt .-% in the aqueous contain gene alkyldiketene dispersion. Usually the finely divided, aqueous dispersions of component (A) in the Made in such a way that first the at least 95% amylo starches containing pectin into a water-soluble form leads. This can be done, for example, using an oxidative or hydrolytic degradation in the presence of acids or by mere Heating the cationic starches are done. Unlocking the Starch is preferred in a jet cooker at temperatures in the Range from 100 to 150 ° C made. In the so obtainable aq solution of the cationic starch with a minimum content Amylopectin of at least 95% by weight is then dispersed least a C₁₄ to C₂₂ alkyl diketene at temperatures above 70 ° C, e.g. B. in the range of 70 to 85 ° C. The Alkyldiketen-Dis persion is then cooled so that the alkyldiketenes are solid Form. Finely divided aqueous alkyldiketene is obtained. Dispersions with an average particle diameter of for example 0.5 to 2.5, preferably 0.8 to 1.5 microns. The disper yaw of the alkyldiketenes in water can optionally additionally in the presence of lignin sulfonic acid, condensates of formaldehyde and naphthalenesulfonic acids containing styrenesulfonic acid groups  Polymers or the alkali metal and / or ammonium salts of the ge called compounds containing sulfonic acid groups. These substances act as dispersants and stabilize them resulting alkyl diketene dispersions. If this dispersing used in the manufacture of the alkyl diketene dispersions the amounts used are, for example, 0.01 to 1, preferably 0.02 to 0.2 wt .-%, based on the alkyldi ketene dispersion.

In the preparation of the alkyl diketene emulsions the cationic wax may also strengthen other common ones Protective colloids used in the manufacture of alkyldi ketene emulsions have been used so far, e.g. B. water-soluble cellulose ethers, polyacrylamides, polyvinyl alcohols, polyvinyl pyrrolidones, polyamides, polyamidoamines and mixtures of ge called connections. Component (A) can optionally be white tere substances that are common in alkyldiketene dispersions are, e.g. B. C₁- to C₁₀ carboxylic acids, for. B. formic acid, acetic acid or propionic acid. The acids will, if in the alkyldike dispersions are contained, in amounts of 0.01 to 1 wt .-% used. The alkyldiketene dispersions can optionally still contain common biocides, in amounts up to 1 wt .-% can be turned.

Component (B) of the paper sizes according to the invention mixtures consists of finely divided, aqueous polymer dispersions that are a sizing agent for paper. Such Polymer dispersions are known, for example, from EP-B-0 051 144, EP-B-0 257 412, EP-B-0 276 770, EP-B-0 058 313 and known from EP-B-0 150 003. We as paper sizing agents kenden polymer dispersions are obtained for example Lich that from 1 to 32 parts by weight of a mixture

• (a) styrene, acrylonitrile and / or methacrylonitrile,
• (b) Acrylic acid and / or methacrylic acid esters from C₁ to C₁₈ Alko get and / or vinyl esters of saturated C₂ to C₄ carbon acids and optionally
• (c) other monoethylenically unsaturated copolymerizable Mo nomeren

in aqueous solution in the presence of 1 part by weight of a solution co polymer from

• (1) Di-C₁ to C₄ alkylamino C₂ to C₄ alkyl (meth) acrylates, the can optionally be protonated or quaternized,
• (2) nonionic, hydrophobic, ethylenically unsaturated mono mer, with these monomers, if they poly alone be merized, form and give hydrophobic polymers otherwise
• (3) monoethylenically unsaturated C₃ to C₅ carboxylic acids or ih ren anhydrides, the molar ratio of (1): (2): (3) = Is 1: 2.5 to 10: 0 to 1.5, copolymerized.

A solution copolymer is first prepared in which the Monomers of groups (1) and (2) and optionally (3) in one with Water-miscible organic solvents copolymerized. Yeah gnete solvents are, for example, C₁ to C₃ carboxylic acids, such as Formic acid, acetic acid and propionic acid or C₁- to C₄-Alko get like methanol, ethanol, n-propanol or isopropanol and Ke tone like acetone. The monomers of group (1) are used before preferably dimethylaminoethyl acrylate, dimethylaminoethyl methacrylic lat, dimethylaminopropyl methacrylate and dimethylaminopropylacry lat. The monomers of group (1) are preferably in proto nated or used in quaternized form. Suitable quater Native agents are, for example, methyl chloride, dimethyl sulfate or benzyl chloride.

The group (2) monomers used are nonionic, hydro phobe, ethylenically unsaturated compounds that, when used for polymerize themselves, form hydrophobic polymers. These include, for example, styrene, methylstyrene, C₁ to C₁₈ alkyl esters of acrylic acid or methacrylic acid, for example Methyl acrylate, ethyl acrylate, N-propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate and isobutyl acrylate and iso butyl methacrylate, n-butyl methacrylate and tert-butyl methacrylate. Acrylonitrile, methacrylonitrile, vinyl acetate, Vinyl propionate and vinyl butyrate. Mixtures of Mo. Use group 2 nomers in the copolymerization, e.g. B. Wed. mixtures of styrene and isobutyl acrylate. The emulsifier Solution copolymers may optionally also contain monomers of Polymerized group (3) contain, for. B. monoethylenic saturated C₃ to C₅ carboxylic acids or their anhydrides, e.g. B. Acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic acid drid or itaconic anhydride. The molar ratio of (1): (2): (3) is 1: 2.5 to 10: 0 to 1.5. The so get The copolymer solutions are diluted with water and serve in this form as a protective colloid for the polymerization of Monomer mixtures from components (a) and (b) given above  and optionally (c). The monomers of group (a) are Sty rol, acrylonitrile, methacrylonitrile or mixtures of styrene and Acrylonitrile or styrene and methacrylonitrile. As Monomers of group (b) use acrylic acid and / or meth acrylic esters of C₁ to C₁₈ alcohols and / or vinyl esters of saturated C₂ to C₄ carboxylic acids. This group of monomers corresponds to the monomers of group (2), which are already above was written. Preferably used as the monomer Group (b) butyl acrylate and butyl methacrylate, e.g. B. acrylic acid isobutyl acrylate, acrylic acid n-butyl acrylate and Methacrylic acid isobutyl acrylate. Monomers of group (c) are in for example C₃- to C₅-monoethylenically unsaturated carboxylic acids, Acrylamidomethylpropanesulfonic acid, sodium vinyl sulfonate, vinyl imidazole, N-vinylformamide, acrylamide, methacrylamide and N-vinyl imidazoline. 1 is used per 1 part by weight of the copolymer up to 32 parts by weight of a monomer mixture of components (a) to (c). The monomers of components (a) and (b) can be copolymerized in any ratio, e.g. B. in Molar ratio 0.1: 1 to 1: 0.1.

The monomers of group (c) become Modifi if necessary Adornment of the properties of the copolymers used.

Preferably, they are described as sizing agents for paper NEN finely divided, aqueous dispersions used from the EP-0 257 412 and EP-B-0 276 770 are known. This disper ions are obtained by copolymerizing

• (a) 20 to 65% by weight of styrene, acrylonitrile and / or methacrylni tril,
• (b) 80 to 35% by weight of acrylic acid and / or methacrylic acid esters of monohydric saturated C₃ to C₈ alcohols and
• (c) 0 to 10% by weight of other monoethylenically unsaturated copoly merizable monomers

prepared in the presence of free radical initiators in the manner of an emulsion polymerization in an aqueous solution of a degraded starch as a protective colloid. The degraded starch preferably has viscosities η _i = 0.04 to 0.50 dl / g. These starches have been subjected to oxidative, thermal, acidolytic or enzymatic degradation. All native strengths can be used for this degradation, e.g. B. starches from potatoes, wheat, rice, tapioca and corn and starches with amyl lopectin content of at least 95, preferably 98 to 100 wt .-%, z. B. waxy corn starch, waxy potato starch, zen starch wax or mixtures of the starches mentioned. In addition, chemically modified starches can be used, such as starches containing hydroxyethyl, hydroxypropyl or quaternized aminoalkyl groups and having viscosities in the range given above. Oxidative degraded potato starches, cationized, degraded potato starches or hydroxyethyl starch are particularly suitable. The mixture of size-acting copolymer dispersion and an undigested starch is preferably stirred for at least 10 minutes at 85.degree. This unlocks the strength.

The degraded starches act as emulsifiers in the copolymer sation of the monomers (a) to (c) in an aqueous medium of the type ei emulsion polymerization. The monomers are in an aq copolymerized gene solution that 1 to 21, preferably 3 to Contains 15% by weight of degraded starch. In 100 parts by weight of a sol Chen solution is usually polymerized 10 to 140, preferably 40 to 100 parts by weight of the monomer mixture from (a) and (b) and possibly (c). The diameter of the dispersed polymer particles is 50 to 350, preferably 100 to 250 nm. As the monomer of Group (b) also have vinyl esters from C₂ to C₄ sown taken into account carboxylic acids. Suitable monomers of Group (c) are, for example, acrylamide, methacrylamide, Stearyl acrylate, stearyl methacrylate, palmity acrylate, acrylic acid, Methacrylic acid, maleic acid, maleic anhydride, itaconic acid, Vinylsulfonic acid, actylamidopropanesulfonic acid and acrylic acid and Methacrylic acid esters of amino alcohols, e.g. B. Dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropylacry lat and dimethylaminomethacrylate.

The paper size mixtures according to the invention are after known methods, see. DE-A-32 35 529 and WO-A-94/05855. One proceeds, for example, in such a way that (A) finely divided, aqueous dispersions of C₁₄- to C₂₂-alkyldi ketenes, which are obtained by dispersing the alkyldiketenes in water Presence of cationic starch with an amylopectin content of at least 95% are available with (B) finely divided, aqueous Polymer dispersions, which are a sizing agent for paper with mixes each other or C₁₄- to C₂₂-alkyldiketenes in a mixture from aqueous solutions of cationic starches with an amylo pectin content of at least 95%, the strengths being in what water-soluble form and finely divided, aqueous Polymer dispersions that are a sizing agent for paper Emulsified temperatures of at least 70 ° C. The emulsification takes place here preferably under the influence of high shear forces, e.g. B. in so called homogenizers. The resulting emulsions are preferably rapidly cooled to room temperature. That accrue The dispersions of paper sizing mixtures have one  pH in the range from 2 to 4, preferably the pH is at 3. The paper sizing mixtures can also in the Be prepared by components (A) and (B) mixes, e.g. B. in a stirred tank and this mixture given if under the action of high shear forces at temperatures of homogenized for example 20 to 70 ° C. The invention Paper sizing mixtures contain, for example, 1 to 55, preferably 10 to 30% by weight of alkyl diketenes and 1 to 60, preferably 3 to 25% by weight of finely divided polymer dispersions, each based on the solids.

For the production of the paper sizes according to the invention for example, 1 part by weight (diketene) component (A) 0.1 to 1.2, preferably 0.3 to 0.9% by weight Parts of polymer dispersion of component (B), based on the Solids. One can, for example, a single finely divided water polymer dispersion or a mixture of 2 or more Use polymer dispersions, each a sizing agent for Are paper. The particle diameter of the finely divided aqueous Polymer dispersions is preferably 50 to 400, for example as 100 to 250 nm. The sizing agents according to the invention Schungen are stable in storage, d. that is, they do not tend to segregate and don't get stuck either. You also have a very low viscosity (e.g. after storage of The viscosities are below 90 days at room temperature 100 mPas, measured in a Brookfield viscometer 100 rpm, and a temperature of 25 ° C with spindle No. 1) and are also characterized by a high stability against the Influence of shear forces, such as those in the pump pen occur. The sizing mixtures are called bulk and Surface sizing agent used for paper, cardboard and cardboard. Use as a mass sizing agent is preferred in the manufacture provision of paper.

The percentages in the examples mean% by weight, the parts are parts by weight.

Examples Polymer dispersion 1

In a 1 liter four-necked flask equipped with a stirrer, reflux condenser, Do siervorrichtung and a device for working under stick atmosphere, 34.0 g of starch A and 8.4 g of starch B suspended in 148 g of water and stirred on Heated to 85 ° C.

Starch A is a degraded cationic potato starch with a viscosity η _i of 0.47 dl / g, a degree of substitution of 0.015-COOH and 0.027 N mol / mol glucose units and a solids content of 83%.

Starch B is a degraded, cationic potato starch with a viscosity η _i of 1.16, a degree of substitution of 0.07 N mol / mol glucose units and a solids content of 83%.

After 30 minutes at 85 ° C, 2.6 g of an aqueous 10% Cal cium acetate solution and 10 g of a 1% enzyme solution (α-amylase A) added. After another 20 minutes at 85 ° C the enzymatic Starch degradation stopped by adding 1.5 g of glacial acetic acid. Then 16.5 g of a 1% iron (II) sulfate solution and 1.75 g 30% hydrogen peroxide added. After 20 minutes it is Hydrogen peroxide decomposes and the oxidative starch degradation has ended det. The intrinsic viscosity of the starch mixture is then 0.08 dl / g. Then 1.8 g of 30% hydrogen peroxide are added and begins immediately with an emulsion consisting of 93.7 g acrylonitrile, 76.4 g of n-butyl acrylate and a solution of 0.2 g of Na-C₁₄ alkylsul fonat in 50 g of water, evenly within 1 hour and 50 g of 3.12% water separately at the same time Add peroxide solution within 1.75 hours. While this time and 60 minutes after the end of the monomer dose tion, the temperature of the reaction mixture is kept at 85 ° C. A dispersion with a solids content of 41.0% is obtained. and a particle diameter (without starch shell) of 100-150 nm. The dispersion is added to egg by adding water diluted solids content of 33%.

Polymer dispersion 2

A mixture of 20 parts (1.92 mol) styrene, 7 parts (0.41 mol) dimethylaminopropyl methacrylamide, 3.5 parts (0.486 mol) acrylic acid and 10 parts acetic acid was added inside of 1 hour using a pump in a heated to 90 ° C Pumped boiler. Simultaneously and also within 1 hour  you added 2 parts of Azo using another dosing device isobutyronitrile and 10 parts of acetic acid. The mixture was heated to a temperature of 90 ° C for 30 min and then in Dissolved 180 parts of water. Then 0.01 part of iron sulfate was added and polymerized a Mi therein at a temperature of 85 ° C 32 parts of styrene and 32 parts of isobutyl acrylate. Sepa Of these, 33 parts of a 6% hydrogen peroxide solution were given continuously to the prepolymer within 2 hours.

After post-polymerization for 1 hour at a temperature of 85 ° C resulted in a finely divided dispersion with a solids content of 31.4% and a particle diameter of 150-250 nm Dispersion is achieved by adding water to a solids content diluted by 20%.

example 1

A 2.80% aqueous solution of a commercially available solution is prepared cationic waxy maize starch (D.S. 0.03, amylopectin content <98%) by putting the required amount of starch in water suspended and the suspension at a temperature for 15 minutes at 95 ° C. Adds to 85 parts of the starch solution available in this way 15 parts of the polymer dispersion 1 are obtained at a temperature of 85 ° C. to. The mixture is stirred for 10 minutes.

To 84 parts of the mixture of waxy corn starch described above and polymer dispersion 1 are 16 parts of a C₁₆ / C₁₈ alkyldike melt and treat the mixture briefly with an ultratur rax. This mixture is then in twice at 150 bar homogenized using an intensive mixer. The emulsion then becomes rapid cooled to room temperature. The properties of the sizing agent tle dispersion are given in Table 1.

Example 2

A 3.66% aqueous solution of a commercially available solution is prepared cationic waxy maize starch (D.S. 0.03, amylopectin content <98%) by adding the required amount of starch in What water suspended and the suspension in the jet cooker at a Temperature of 125 ° C. To 65 parts of the so available Starch solution is added at a temperature of 85 ° C 35 parts of the Polymer dispersion 2 too. The mixture is then 10 min. touched.

84 parts of the mixture described above from the aqueous solution the digested cationic starch and the polymer dispersion 2 gives 16 parts of a C₁₆ / C₁₈ alkyldiketenschmelze and briefly treated the mixture with an Ultraturrax. These  Mixture is then twice in a homogenizer at 150 bar acts and then quickly cooled to room temperature. The own Properties of the paper size mixture are shown in Table 1 give.

Example 3

A 4.17% aqueous solution of a commercially available solution is prepared cationic waxy maize starch (D.S. 0.04, amylopectin content <98%) in which the starch is first suspended in water and in a jet cooker at a temperature of 125 ° C closes. Then add 0.1 part of the starch solution Sodium salt of a lignosulfonic acid and then 20 parts a C₁₆ / C₁₈ alkyl diketene melt and treats the mixture with an Ultraturrax. The initially coarse suspension twice through a homogenizer at a temperature of 85 ° C and a pressure of 150 bar and then quickly cooled to room temperature.

90 parts of the alkyldiketene dispersion described above then together with 10 parts of polymer dispersion 1 with stirring which is mixed and twice in a homogenizer under one Treated pressure of 150 bar. The properties of paper Mixtures of agents are given in Table 1.

Example 4

A commercially available cationic waxy maize starch (D.S. 0.04, Amy lopectin content 100%) is in such an amount in water worn that a 4.17% aqueous suspension is formed. These Suspension is then in a jet cooker at a temperature of Opened 125 ° C, so that an aqueous starch solution is obtained which is 0.15 parts of the sodium salt of a lignosulfonic acid and then adds 25 parts of a C₁₆ / C₁₈ alkyl diketene melt. The Mix first with an Ultraturrax and then twice in a homogenizer under a pressure of 150 bar and one Treated temperature of 85 ° C and then quickly to room temperature temperature cooled.

70 parts of the alkyl diketene emulsion described above are added Add 30 parts of polymer dispersion 2 and homogenize the resulting Mix twice in a homogenizer at a pressure of 150 bar. The properties of the paper sizing agents available in this way Table 1 shows the mixture.  

Comparative Example 1

A 5.13% aqueous suspension of a han is first prepared standard cationic starch (D.S. 0.02, amylopectin content 70%), gave 50 parts of this suspension to 50 parts of the Polymer dispersion 1 and closed the starch by 10 minutes Heat in the mixture with the polymer dispersion 1 to one Temperature of 85 ° C.

To 78 parts of the mixture of the digested starch and the Polymer dispersion 1 was given a melt heated to 90 ° C. 20 parts of stearyl diketene and 2 parts of stearic acid oleate and The mixture was then homogenized as in Example 1 wrote. A stable, 20% strength aqueous stearyl dike was obtained tenemulsion, which apart from stearyl diketene 2% starch, 2% stearic acid reole ester as stabilizer and 12.9% of the polymer dispersion 1 contained. The properties of the dispersion are shown in Table 1 given.

Comparative Example 2

Example 1 was repeated with the changes that one 5.13% aqueous suspension of a commercially available cationic Starch (degree of substitution 0.02, amylopectin content 75%) , mixed with 50 parts of polymer dispersion 2 and die Starch by heating the mixture to 85 ° C for a total of 10 minutes unlocked. To 78 parts of the mixture thus obtained from closed strength and polymer dispersion 2 were then given up 90 ° C heated melt from 20 parts of stearyl diketene and 2 parts Stearic acid oleylester and emulsified the melt in it as in Example 1 given. The properties of sizing agents are given in Table 1.  

Table 1

The shear stability of those in the examples and comparative sizing agent mixtures described in examples were determined, by passing the mixtures through with a centrifugal pump 400 µm filter pumped. 500 ml of the paper egg was used in each case mixture and kept the temperature of the mixture during of the test at 25 ° C. The times are given in Table 2 after which the filter becomes blocked or the experiment is stopped has been.

Table 2

Shear stability test (pump test)

Claims (13)

1. Paper sizing mixtures

• (A) finely divided, aqueous dispersions of C₁₄- to C₂₂- alkyldiketenes, which can be obtained by dispersing the alkyldiketenes in water in the presence of cationic starch, and
• (B) finely divided, aqueous polymer dispersions which are a size for paper,

characterized in that the amylopectin content of the cat ionic starch of component (A) is at least 95%. 2. paper sizing mixtures according to claim 1, characterized ge indicates that the amylopectin content of the cationic Thickness is 98 to 100%. 3. paper sizing mixtures according to claim 1, characterized ge indicates that the cationic strength is a cationic Is waxy corn starch. 4. paper sizing mixtures according to one of claims 1 to 3, characterized in that in the manufacture of the compo nente (A) dispersing the alkyldiketenes in water additionally in the presence of lignosulfonic acid, condensates Formaldehyde and naphthalene sulfonic acids, styrene sulfonic acid group-containing polymers or the alkali metal and / or contain ammonium salts of the sulfonic acid groups mentioned tendency connections. 5. Process for making paper sizing mixtures by mixing

• (A) finely divided, aqueous dispersions of C₁₄- to C₂₂- alkyldiketenes, which can be obtained by dispersing the alkyldiketenes in water in the presence of cationic starch
• (B) finely divided, aqueous polymer dispersions which are a size for paper,

or by emulsifying C₁₄ to C₂₂ alkyl diketenes in one Mixture of aqueous suspensions of cationic starches and finely divided, aqueous polymer dispersions that have a lei are for paper, at temperatures of at least 70 ° C, characterized in that the amylopectin content of cationic strengths is at least 95%. 6. The method according to claim 5, characterized in that the Amylopectin content of the cationic starches 98 to 100% wearing. 7. The method according to claim 5 or 6, characterized in that one uses cationic waxy maize starches. 8. The method according to any one of claims 5 to 7, characterized records that the degree of substitution (D.S.) of the cationic Thicknesses is 0.010 to 0.150. 9. The method according to claim 8, characterized in that the Degree of substitution (D.S.) of the cationic strengths below of 0.045. 10. The method according to claim 8, characterized in that the Degree of substitution (D.S.) of the cationic starches 0.020 to Is 0.040. 11. Use of the paper size mixtures according to the An sayings 1 to 4 as mass and surface sizing for Paper, cardboard and cardboard.