CS256868B1 - Paper size and method of preparation - Google Patents

Abstract

The present invention relates to the composition and method of preparing water-soluble sizing agents based on natural and synthetic resins. Its purpose is to increase the long-term stability of sizing agents and the mechanical properties and durability of their wetted paper products. This is accomplished by refolding the basic binder component of the sizing agent consisting of salts derived from inorganic and / or organic bases and mixtures of specified polymeric carboxylic acids with resin acids and / or derivatives thereof in weight. on the other hand, a preferred process for the preparation of these sizing agents by melting and homogenizing the resin components, neutralizing the mixture with said bases and optionally further treating the resulting salts with the addition of water and other additives.

Description

SUMMARY OF THE INVENTION The present invention relates to paper sizing agents based on mixed, water-dilutable alkaline salts of polymeric carboxylic acids, resin acids and / or derivatives thereof and a process for their preparation. They can be applied when sizing paper in the mass and during glueing. Sizing agents based on natural and synthetic materials are used in the paper industry (V. Hnětkovský et al.: Paper Handbook. Prague, SNTL 1983). Natural sizing agents are traditionally represented by waxes, proteins, starches, especially rosin and its derivatives (German Patent No. 1,467,545, U.S. Pat. No. 3,400,117; 3,565,755; 3,817,768; British Patent 1,026,945). More recently, synthetic sizing agents include aldoketene dimers (NSR Patent 2,848,194, U.S. Pat. No. 4,243,481, 4,382,129), hydrocarbon resins (U.S. Pat. No. 226,224, Japanese Patent No. 8,100,399, 8,238,838). , U.S. Patent No. 2,434,216, U.S. Patent No. 3,953,407) and various high molecular weight compounds.

Said sizing agents, in the form of aqueous solutions or pastes, come mainly as aqueous dispersions, optionally also as dry products. They are used to size paper either in the mass (internal sizing) or its surface (surface sizing). Sizing the paper achieves its resistance to the penetration of liquids, especially water and ink. However, the most commonly used rosin is not available in sufficient quantities worldwide, and its composition and purity according to provenance are very varied. Synthetic sizing does not have these drawbacks and allows them to produce well-defined products. However, these are often only applicable to a particular method of sizing some special types of paper. Their synthesis, for example dimeraldoketenes, is very difficult and expensive. Most macromolecular substances have only a low size and are more suitable as a binder for papermaking compositions. The present invention removes the above drawbacks of paper sizing agents in large part and further improves their properties. It relates to the composition of paper-based sizing agents based on mixed, water-soluble salts of natural and synthetic resins and optionally additives and a process for their preparation. The sizing agents of the present invention consist of 20 to 99 parts by weight of a water-soluble resin component, 1 to 80% by weight. parts of water and optionally up to 25 wt. parts of additives, particularly supportive sizing agents, wherein the sizing agent comprises, as a water-soluble resin component, salts of inorganic and / or organic bases and mixtures of polymeric carboxylic acids having an average molecular weight of 500 to 20,000 and a carboxyl group content of 45 to 40% 125 g / 1000 g with resin acids and / or derivatives thereof, especially with adducts of alpha-beta-unsaturated carboxylic acids with 3 to 6 carbon atoms or their anhydrides, with a softening point of 50 to 120 ° C and carboxylic acid groups of 40 to 180 g / 1000 g in a 0.95: 0.05 to 0.05: 0.95 weight ratio. The essence of the preparation of these sizing agents is that they are melted individually or together at a temperature of 90 to 210 ° C and then a total of 1000 wt. parts of a mixture of polymeric carboxylic acids having an average molecular weight of 500 to 20,000 and containing 45 to 125 gCOOH / 1000 g with resin acids and / or derivatives thereof, in particular with alpha; beta - unsaturated carboxylic acids with 3 to 6 carbon atoms or their % anhydride, with a softening temperature of 50 to 120 ° C and a content of 40 to 180 g COOH / 1000 g in wt. from 0.95 to 0.05 to 0.05: 0.95, the mixture obtained is partially or completely neutralized by the addition of 10 to 180 wt. inorganic and / or organic bases.

The resulting salts are optionally dissolved in about 5,900 wt. optionally, up to 25 wt. parts of additives. The polymeric carboxylic acids and / or carboxylic acid derivatives of the resins are preferably prepared in the first stage of the preparation of sizing agents by reacting the .alpha.,. Beta.-unsaturated carboxylic acids with 3-6 carbon atoms or their anhydrides with unsaturated polymers and / or resin acids. temperature of 150 to 210 ° C. . Paper sizing agents according to the invention have some advantages over known sizing agents. They can be produced in a very wide range of polymeric carboxylic acid compositions, resin acids and / or derivatives thereof. Their alkaline salts are water-dilutable and the aqueous solutions are stable over the long term. 3 256868

They do not exclude crystalline fractions and do not tend to foam. They can be applied to normal internal and surface sizing, where a high degree of squeezing of almost all kinds of paper, cardboard and cardboard is achieved. At the same time, their mechanical properties, especially wet resistance, increase.

The major constituents of the papermaking sizing agent of the present invention are the alkali salts of mixtures of polymeric carboxylic acids, resin acids, and / or derivatives thereof. The polymeric carboxylic acids have an average molecular weight of 500 to 20,000 and a content of 45 to 125 gCOOH / 1000 g. They are primarily 3 to 6 carbon atom alpha, beta-unsaturated carboxylic acid copolymers or their anhydrides or their adducts with unsaturated polymers. acids include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, pyrlcinchonic acid, mesaconic acid, and itaconic acid. Of the anhydrides, maleic anhydride is most important. Their comonomers are monoolefins (for example, ethylene, propylene, butenes, pentenes, hexenes, heptenes, vinyl chloride, vinylidene chloride, vinyl acetate, (meth) acrylic and allyl compounds, cyclopentenes, cyclohexenes, styrene, vinyltoluene, cumene, indenes) and diolefins (butadiene , isoprene, p.perylene, dimethylbutadiene, chloroprene, penta-dienes, hexadienes, cyclopentadiene, cyclohexadiene, dicyclopentadiene). For copolymerization with unsaturated acids, either single monomers with one or two double bonds, or different mixtures thereof, may be used. Instead of said comonomers, their liquid oligomers, co-oligomers or low molecular weight homopolymers and copolymers containing double bonds can be used for copolymerization or addition.

Thus, the described types of polymeric carboxylic acids are either copolymers which are prepared by Friedel-Crafts (ionic) polymerization at temperatures of 10 to 70 ° C under the catalysis of the BF-1 complex and the like, or may be alpha, beta-adducts of unsaturated carboxylic acids having from 3 to 6 carbon atoms or their anhydrides with unsaturated polymers. The adducts are prepared at temperatures of 150 to 230 ° C.

The latter acid component comprises resin acids (rosin). Obtained from wood, balsamic resin and crude tall oil. They are mainly based on unsaturated abietic acid and levopimaric acid, further on neoabietic, dehydroabietic, hydro-agetic, palustric, dextropimaric and isodextropimaric acids. Among the technically important derivatives of resin acids are in particular their adducts with the abovementioned alpha, beta-unsaturated carboxylic acids or their anhydrides, mainly with maleic anhydride. Further, reaction products with formaldehyde, hydrogenated and polymerized resin acids are suitable. Products having a softening point of 50 to 120 ° C and a content of 40 to 180 gCOOH / 1000 g are used. They are combined with polymeric carboxylic acids in mass. a ratio of 0.05: 0.95 to 0.95: 0.05.

Both inorganic and organic bases are suitable for the formation of salts of the described polymeric carboxylic acids and resin acids or their derivatives. The most widely used are hydroxides and carbonates of alkali metals (lithium, sodium, potassium and cesium), mainly sodium hydroxide and potassium hydroxide. Further, ammonium hydroxide and water-soluble amines (ethylamine, propylamine, butylamine, secondary and tertiary amines, aminoalcohols, etc.) are suitable. Said bases are added in an amount which is equivalent or also greater or less than the carboxyl groups present. The full or partial salts are then mixed with 1-80 wt. parts of water. Usually, the water used is softened, demineralized or deionized.

Optionally, up to 25 wt. parts of additives, particularly sizing agents. These include wax substances (beeswax, carnauba, montan, ozokerite, ceresin, paraffin), protein (casein, gelatin, soy protein), starch (starch, dextrin, iodized, hydroxyethylated and cationic starch) and cellulose (methylcellulose, hydroxyethylcellulose, carboxymethylcellulose and other cellulose derivatives). Synthetic sizing agents are aldoketene dimers (mainly tetradecylketene and hexadecyl ketene), some macromolecular compounds and the like. Other additives 256868 4 can be surfactants, protective colloids, defoamers, biocides, dyes, pigments, fillers and additives. The preparation of the papermaking sizing agent according to the invention preferably comprises a process in which a total of 1000 wt.% Is melted and homogenized individually or together at 90-150 ° C. parts of a mixture of polymeric carboxylic acids with resin acids and / or derivatives thereof. They are mixed in a weight ratio of 0.95: 0.05 to 0.05: 0.95. The mixture is partially or completely neutralized with 10 to 180 wt. parts of alkali hydroxides, preferably sodium or potassium hydroxide, and the resulting salts are dissolved in deionized water, if necessary, with additives. This gives a 20% water-dilutable product with a pH of 6 to 11, which is suitable for both internal and surface sizing of all kinds of paper, cardboard and paperboard. it can also be prepared by obtaining the starting polymeric carboxylic acids and / or carboxylic acid derivatives of the resin acids only in the first phase of the self-technological process. In this case, they react at 150 DEG-210 DEG C. with the .alpha., .Beta.-unsaturated carboxylic acids or their anhydrides with unsaturated polymers and / or acid acids. The invention is further illustrated by the following examples. The softening temperatures of the resin acids and their derivatives were determined according to CSN 65 7060. The examples used are characterized as follows:

Polymeric Carboxylic Acid I

It was prepared by reaction according to Friedl-Craft from pentene-hexene-cyclopentadiene-piperylene-indene-maleic anhydride. It has a molecular weight of 4,000 and contains 125 g of COOH / 1000 g of polymeric acid.

Polymeric Carboxylic Acid II

It was prepared by reaction according to Friedl-Craft from pentene-hexene-butadiene-indene-cyclo-pentadiene-maleic anhydride. It has a molecular weight of 500 and contains 50 g COOH / 1000 g polymeric acid.

Polymeric Carboxylic Acid III

It was prepared by anionic polymerization of 1,3-butadiene and acrylic acid. It has a molecular weight of 20,000 and contains 110 g of COOH / 1000 g of polymeric acid.

Polymeric Carboxylic Acid IV

It was prepared by radical polymerization of styrene, methyl methacrylate and acrylic acid to a molecular weight of 15,000 and a content of 80 g COOH / 1000 g polymeric acid.

Resin Acid A

Partially hydrogenated rosin with a softening point of 85 ° C and a content of 120 g COOH / 1000 g resin; .

Resin acid. B

It was obtained by fractionated distillation of crude tall oil with a softening point of 55 ° C and a content of 40 g of COOH / 1000 g of resin.

Resinic acid C

Adduct 90 wt. parts of resin acid A and 10 wt. parts of maleic anhydride with a softening point of 95 ° C and a content of 160 g of COOH / 1000 g of resin. 5 256868

Resinic acid D. .

Adduct 85 wt. parts of resin acid A and 15 wt. parts of maleic anhydride at a temperature of 110 ° C and a content of 180 g COOH / 1000 g resin. Example 1

The resin size consists of 95 wt. parts of potassium salts of polymeric carboxylic acid I and 5 wt. parts of the potassium salt of the resin acid A. In the preparation, 950 wt. parts of polymeric carboxylic acid I and 50 wt. The mixture was heated to 150 ° C under nitrogen and 157 wt. solid KOH. The temperature was kept constant with stirring for 2 h, then the mass was cooled, diluted with 2 167 wt. parts of demineralized water and 167 wt. parts of bleached beeswax. The dose of absolutely dry sizing for absolutely dry fiber (ash in paper 9.6% w / w) is 4.0% w / w, the final degree of caving according to Cobb is 28 gm.

The paper size consists of 5 wt. parts of sodium salts of polymeric carboxylic acid II, 15 wt. parts of the sodium salts of resin acid A and 80 wt. 50% by weight of resin acid C parts. parts of polymeric carboxylic acid II, 150 wt. parts of resin acid A and 800 wt. The mixture was heated to 150 ° C under nitrogen and 132 wt. The solids were kept under stirring for 2 h, then the mass was cooled and diluted with 1 273 wt. parts of demineralized water. The dose of absolutely dry sizing agent for absolute dry fiber (paper ash 9.6% -2 wt.) Is 1.2 wt.%. and the resulting Cobb staging step is 20 g.m Example 3

The paper size consists of 10 wt. parts of potassium salts, polymeric carboxylic acids III and 90 wt. parts of the potassium salt of resin acid B are prepared by adding 100 wt. parts of polymeric carboxylic acid III, 809 wt. parts of resin acid B and 91 wt. The mixture was heated to 200 ° C under nitrogen flow and 87 wt. parts of solid COH. While stirring, the temperature is maintained for 2 h, then the mass is cooled and diluted with 333 wt. parts of demineralized water. The dose of absolutely dry sizing agent for absolute dry fiber ("-2 in paper 9.6% by weight") is 1.6% by weight. and the resulting Cobb staging degree is 19 g.m Example 4

The paper size consists of 20 wt. parts of ammonium salts of polymeric carboxylic acid IV and 80 wt. 200 parts by weight of ammonium salts of resin acid D are added. parts of polymeric carboxylic acid IV and 800 wt. The mixture is heated to 150 ° C under an inert atmosphere, then cooled to 100 ° C and 50 wt. parts of 25% ammonia and 323 wt. parts of triethylamine for continuous stirring. It is left for 2 h and then diluted with 3000 wt. parts of demineralized water. The dose of absolutely dry sizing agent for absolutely dry fiber (9.6% w / w paper) is -21.2% w / w. and the resulting Cobb staging degree is 21 g.m

Claims (3)

256868 6 OBJECT OF THE INVENTION 1. Paper glue based on mixed, water-soluble salts of natural and synthetic resins and additives, consisting of 20 to 99 wt. parts of a water-dilutable resin component, 1 to 80 wt.% of water and optionally up to 25 wt. parts of additives, in particular supportive sizing agents, characterized in that they contain, as the water-soluble resin component, saline and / or organic bases and mixtures of polymeric carboxylic acids having an average molecular weight of 500 to 20,000 and a carboxyl content of 45 to 125 g / 1000 g with resins acids and / or derivatives thereof, especially with adducts of alpha, beta-unsaturated carboxylic acids with 3 to 6 carbon atoms or anhydrides, with a softening point of 50 to 120 ° C and a carboxyl content of 40 to 180 g / 1000 g , in a weight ratio of 0.95: 0.05 to 0.05: 0.95. 2. A process for preparing papermaking sizing agents according to claim 1, characterized in that a total of 1000 parts by weight of a mixture consisting of polymeric carboxylic acids having an average molecular weight of 500 to 20,000 and a content of polymeric carboxylic acids is individually or together melted together and then homogenized. 45 to 125 g of COOH / 1000 g and resin acids and / or their derivatives, in particular adducts with alpha, beta-unsaturated carboxylic acids with 3 to 6 carbon atoms or their anhydrides, with a softening point of 50 to 120 ° C and a content of 40 to 180 g COOH / 1000 g in wt. from 0.95: 0.05 to 0.05: 0.95 and partially or completely neutralized by addition of 10 to 180 wt. parts of inorganic and / or organic bases are then dissolved in up to 5,900 wt. and up to 250 parts by weight of additives are optionally added to the solution. 3. Process according to claim 2, characterized in that the polymeric carboxylic acids and / or the carboxylic acid derivatives of the resin acids are only prepared in the first stage of the preparation of the paper inlays by reacting the .alpha.,. Beta.-unsaturated carboxylic acids with 3 to 6 carbon atoms or their anhydrides. unsaturated polymers and / or resin acids at 150 to 210 ° C.