JPH048560B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a paper coating composition containing a specific dispersant, more specifically, it uses a dispersant containing a sulfonic acid group to improve dispersion stability, water resistance, coatability at high speed coating, and coating layer. The present invention relates to a paper coating composition with excellent properties. Conventionally, aqueous dispersion compositions comprising pigments, fillers, pigment binders, and dispersants have been widely used as paper coating compositions. As for the performance required for this paper coating composition, it is necessary that the dispersion stability of pigments, fillers, etc. in the paper coating composition be excellent. If the dispersion stability of pigments and fillers is poor, the pigments and fillers will not be dispersed uniformly or will separate, resulting in non-uniform compositions, resulting in the inability to obtain coated paper with the desired performance, or in some cases. In some cases, coating may become impossible, which is undesirable.(2) There is a tendency for coating speeds to increase in order to improve productivity. Therefore, it has become necessary to have excellent coating properties and coated layer properties in high-speed coating. Conventional methods for improving the dispersion stability of pigments, fillers, etc. in paper coating compositions include adding sodium polyacrylate, sodium hexametaphosphate, sodium tripolyphosphate, surfactants, etc. However, the improvement in dispersion stability is not sufficient, and a large amount must be used to obtain sufficient dispersion stability. If a large amount is used, the viscosity of the coating composition liquid increases, making it difficult to handle and causing problems in workability. As described above, paper coating compositions using conventional dispersants have not been satisfactory in terms of dispersion stability and viscosity of the coating composition liquid. Furthermore, the coating properties, appearance and performance of the coated layer when coated at high speed using conventional paper coating compositions were not satisfactory, and the water resistance was also insufficient. As a result of extensive research aimed at obtaining a paper coating-like composition with excellent dispersion stability and water resistance, no increase in viscosity, high-speed coating properties, and coating layer properties, the present inventors found that The use of a sulfonic acid group-containing dispersant resulted in a completely unexpected result that a paper coating-like composition having the above-mentioned excellent performance could be obtained, and based on this knowledge, the present invention was completed. That is, the present invention provides that (A) a high condensate of naphthalene sulfonate, a condensate of alkylaryl sulfonate, a condensate of triazine sulfonate, a condensate of anthracene sulfonate, lignin, based on 100 parts by weight of the pigment. At least one dispersant selected from the group of sulfonates, cocondensates of lignin and naphthalene sulfonates, and compounds that essentially contain a tricyclodecane or tricyclodecene skeleton and a sulfonic acid group in the molecule.
The present invention provides a paper coating composition characterized in that it contains 0.005 to 5 parts by weight (B) and 1 to 40 parts by weight of a pigment binder. The pigment of the present invention is a pigment for paper, such as light calcium carbonate, heavy calcium carbonate, clay,
Examples include inorganic pigments such as satin white, titanium dioxide, aluminum hydroxide, and talc, and organic pigments such as polystyrene. The dispersant of the present invention includes a high condensate of naphthalene sulfonate, a condensate of triazine sulfonate, a condensate of alkylarisulfonate, a condensate of anthracene sulfonate, lignin sulfonate, lignin and naphthalene. Examples include co-condensates of sulfonate salts and compounds that essentially have a tricyclodecane or tricyclodecene skeleton and a sulfonic acid group in the molecule. The above-mentioned dispersants also include those obtained by copolymerization or cocondensation with other copolymerizable or cocondensable compounds. As a sulfonate constituting a high condensate of naphthalene sulfonate, a condensate of triazine sulfonate, a condensate of anthracene sulfonate, a condensate of lignin sulfonate, or a co-condensate of lignin and naphthalene sulfonate. Examples include sodium salts, potassium salts, and ammonium salts. Further, as the compound containing a tricyclodecane or tricyclodecene skeleton and a sulfonic acid group in the molecule, at least one compound selected from the following () to () is used. In the present invention, the tricyclodecane skeleton or tricyclodecene skeleton is shown as follows. ((a), (b)) (i.e. tricyclo [5.2.1.0 ^2.6 ] decane or decene) () A sulfonated product obtained by sulfonating a polymer obtained by polymerizing cyclopentadiene or a cyclopentadiene derivative represented by general formula (a) or general formula (b) as shown in JP-A-58-152861. . (In the formula, R ₁ is a hydrogen atom or a carbon atom number of 1 to
3 represents an alkyl group. ) (In the formula, R ₂ and R ₃ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.) () General formula (a) as shown in JP-A-58-152862 or a sulfonated product obtained by sulfonating a reaction product mixture obtained by reacting cyclopentadiene or a cyclopentadiene derivative represented by general formula (b) with a compound represented by general formula (c); condensate. (In the formula, R ₄ and R ₅ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.) A condensate obtained by condensing the sulfonated cyclopentadiene derivative shown below. (In the formula, R ₆ , R ₇ and R ₈ are the same or different,
represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ₉ and R ₁₀ are the same or different,
It represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, n represents 1 or 2, and M represents hydrogen, an alkali metal, an alkaline earth metal, ammonium, or ammonium selected from amines. ) () A polymer or copolymer of a sulfonated dicyclopentadiene represented by the general formula (e) as shown in Japanese Patent Application No. 175,666/1982. (In the formula, n and M are the same as in formula (d).) () A polymer of the sulfonated hydroxydicyclopentadiene represented by the general formula (f) as shown in Japanese Patent Application No. 58-43729. Coalescence or copolymer. (In the formula, n and M are the same as in the formula (d).) () Condensation of a disulfonated dicyclopentadiene derivative represented by the general formula (g) as shown in the specification of Japanese Patent Application No. 58-42205. condensate obtained by (In the formula, R ₁₁ and R ₁₂ are the same or different,
It represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, and M and n are the same as in formula (d). ) In the above (), specific compounds that can be represented by general formula (a) or general formula (b) include cyclopentadiene, alkylcyclopentadiene such as methylcyclopentadiene, ethylcyclopentadiene, and propylcyclopentadiene. , or any combination thereof, such as dicyclopentadiene, and preferred examples include cyclopentadiene, dicyclopentadiene, or a mixture of both. Specific compounds that can be represented by the general formula (c) in the above () include, for example, benzene, toluene, xylene (o-, m-, p-),
Ethylbenzene, n-propylbenzene, iso-
Propylbenzene, methylethylbenzene (o
-, m-, p-), n-butylbenzene, sec-butylbenzene, tert-butylbenzene, iso-propyltoluene (o-, m-, p-), amylbenzene, hexylbenzene, amyltoluene (o
Benzene derivatives such as mono- or dialkyl-substituted benzenes such as -, m-, p-), particularly preferred are benzene, toluene,
Examples include xylene, propylbenzene, and butylbenzene. Next, a method for producing the dispersant used in the present invention will be explained. However, the manufacturing methods of the dispersants () to () above are described in JP-A-58-152861, JP-A-58-152862, JP-A-58-152860, and JP-A-Sho 57-, respectively. Specification No. 175666, patent application 1983-
It is described in detail in the specification of No. 43729 and the specification of Japanese Patent Application No. 1983-42205. As an example, the production of a dispersant (2) will be explained. Cyclopentadiene or a cyclopentadiene derivative (general formula (a) or (b)) is treated with an acidic compound catalyst (for example, sulfuric acid, phosphoric acid, hydrogen fluoride, boron trifluoride and its complexes, aluminum chloride, aluminum bromide, tetrafluoride, etc.). tin chloride, zinc chloride, titanium trichloride, etc.) and, if necessary, a solvent such as hydrocarbons or halogenated hydrocarbons, usually at a reaction temperature of -20 to 150°C for several hours. A polymer is obtained by a polymerization reaction. The polymer is preferably treated in the presence of an inorganic oxidizing agent (e.g., nitrates, nitrites, etc.) and a solvent (e.g., water, methyl alcohol, ethyl alcohol, etc.), usually at a reaction temperature of 50 to 200°C, at normal pressure or under elevated pressure. A sulfonation reaction is carried out under pressure using a sulfonating agent such as an acidic sulfite, metasulfite, or sulfite of an alkali metal alone or in a mixture to obtain a sulfonated product. From the viewpoint of ease of sulfonation of the polymer, the preferred number average molecular weight is 10,000.
Below, it is particularly preferably 300 to 5000. The sulfonated product is usually one in which 20 to 100% of the remaining double bonds in the polymer are sulfonated, and the degree of sulfonation is determined by converting the obtained sulfonated product into an acid form by an ion exchange method. It can be determined by alkaline titration. Further, the sulfonated product can be mutually converted into an acid form or a salt of an alkali metal, an alkaline earth metal, ammonium, ammonium selected from amines, etc. by an ion exchange method or a neutralization reaction. An example of the production of the dispersant () will be explained. Cyclopentadiene or a cyclopentadiene derivative (general formula (a) or (b)) and the compound of general formula (c) are reacted in the presence of the above-mentioned acidic compound catalyst and solvent at a reaction temperature of usually -20 to 150°C. A product mixture is obtained. The reaction product mixture is a reaction product obtained by adding one molecule of the compound represented by the general formula (c) to one molecule of dicyclopentadiene, or a reaction product obtained by adding one molecule of the compound represented by the general formula (c) to two molecules of dicyclopentadiene. In addition to several types of adducts such as reaction products to which one molecule of a compound is added, polymers of cyclopentadienes and/or dicyclopentadienes, and compounds represented by the general formula (c) added to the polymers It is a mixture of various compounds such as reaction products (the number average molecular weight of the reaction product mixture is preferably 10,000 or less from the viewpoint of ease of the sulfonation reaction described below). This reaction product mixture is sulfonated by the same method as the polymer sulfonation method described in the above-mentioned method for producing the dispersant (2) to obtain a sulfonated reaction product mixture. The sulfonated product is used as a condensation monomer, and if necessary, other condensation monomers such as benzene, toluene, xylene, and phenol are used in combination, and an acid catalyst (for example, sulfuric acid) is used to dissolve all of the condensation monomers. A condensate is obtained by condensing with an aldehyde (for example, formaldehyde, acetaldehyde, propionaldehyde, etc.) using usually 0.0004 to 10 times the number of moles. The number average molecular weight of the condensate is determined from the viewpoint of dispersion effect,
Preferably it is 500-30000. An example of the production of the dispersant () will be explained. Compounds represented by the following general formula (h) (e.g. benzene, toluene, xylene, propylbenzene, butylbenzene, etc.) and compounds represented by the general formula (i) (e.g. cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene, etc.) mer) in the presence of a catalyst (e.g. sulfuric acid, phosphoric acid, hydrogen fluoride, boron trifluoride and its complexes, aluminum chloride, aluminum bromide, etc.), preferably at 0 to 100°C for 1 to 5 hours. A Kraft reaction is carried out to obtain a compound represented by general formula (j). (R ₆ , R ₇ and R ₈ are the same as in the general formula (d) above) (R ₉ and R ₁₀ are the same as in the general formula (d) above) (R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ are the same as in the general formula (d) above) The compound represented by the general formula (j) is added to the dispersant ()
Sulfonation is carried out in the same manner as the sulfonation method of the polymer explained in the production method, and then, if necessary, an alkali metal, an alkaline earth metal, ammonium, amines, etc. are used to form a sulfonate. A sulfonated product of the cyclopentadiene derivative represented by the general formula (d) is obtained. The sulfonated product is subjected to a condensation reaction in the same manner as the method for producing the condensate explained in the method for producing the dispersant (2) to obtain a condensate. In the general formula (d), n=1 when M is hydrogen, alkali metal, ammonium or ammonium selected from amines, and n=2 when M is an alkaline earth metal. Examples of the alkali metal include sodium and potassium, and examples of the amine include alkylamines such as methylamine, ethylamine, propylamine, dimethylamine, diethylamine, trimethylamine, triethylamine, butylamine, dibutylamine, and tributylamine, ethylenediamine, and diethylenetriamine. ,
Examples of the alkaline earth metal include polyamines such as triethylenetetramine, morpholine, and piperidine, and examples of the alkaline earth metal include calcium, magnesium, and zinc. These metals can also be interchanged with other metals by ion exchange techniques or neutralization reactions. An example of the production of the dispersant () will be explained. The compound of general formula (e) is obtained by sulfonating dicyclopentadiene in the same manner as the polymer sulfonation method explained in the method for producing the dispersant (2), and then converting it into a sulfonate as necessary. It will be done. The compound is subjected to a polymerization reaction in the same manner as the method for producing the polymer explained in the method for producing the dispersant (2) to obtain a polymer. In addition, in the polymerization reaction, if a copolymerizable monomer such as an aliphatic, alicyclic, or aromatic hydrocarbon having an olefinic double bond is present, a copolymer can be obtained. The number average molecular weight of the polymer or copolymer is preferably 500 or more, most preferably 1,500 to 50,000, from the viewpoint of dispersion effect. An example of the production of the dispersant () will be explained. The process is the same as the production of the dispersant (2) except that hydroxydicyclopentadiene is used instead of dicyclopentadiene, which is the starting material for the production of the dispersant (2). The number average molecular weight of the polymer or copolymer is preferably 500 or more, most preferably 1,500 to 50,000, from the viewpoint of dispersion effect. An example of the production of the dispersant () will be explained. Dicyclopentadienes and benzene or benzene derivatives are, for example, in the presence of a boron fluoride catalyst,
The compound of general formula (k) can be obtained by adding, for example, sodium hydrogen sulfite to the reaction product reacted by Friedel-Crafts reaction to form a sulfonate, if necessary. (R ₁ , R ₂ , M are the same as in the general formula (g),
m is 1 or 2. ) The compound of general formula (k) is mixed with a sulfuric acid such as sulfuric acid, sulfuric anhydride, or fuming sulfuric acid using an organic solvent as necessary (the amount of sulfuric acid used is based on the number of moles of the compound of general formula (k)). Preferably 0.1 to 5 times the number of moles) Preferably
When the reaction is carried out at 50 to 150°C, a disulfonated product of general formula (g) is obtained. A condensate is obtained by condensing the disulfonated product using the same condensation method as explained in the production of the dispersant (2). The dispersants listed above can be used alone or in combination of two or more. The amount of dispersant is 0.005 to 5 parts by weight per 100 parts by weight of pigment.
Parts by weight, preferably 0.01 to 2 parts by weight. If the amount of the dispersant is less than 0.005 parts by weight per 100 parts by weight of the pigment, the desired dispersion stability, high-speed coating properties, and coated layer properties cannot be obtained, which is undesirable.
On the other hand, if it exceeds 5 parts by weight, the viscosity increases, and handling workability, high-speed coating properties, and properties of the coated layer are significantly deteriorated, which is not preferable. As the pigment binder of the present invention, any binder used in common paper coating solutions can be used. For example, starch, modified starch, natural binders such as casein, styrene-butadiene copolymer latex, carboxy-modified styrene-butadiene copolymer latex, polyvinyl acetate emulsion, acrylic ester (co)polymer latex , methacrylic acid ester (co)polymer latex, polychloroprene latex, polyvinyl alcohol, and other synthetic binders. The amount of binder used is 1 to 100 parts by weight of pigment.
It is 40 parts by weight. Preferably it is 230 parts by weight. If the amount of the binder used is less than 1 part by weight per 100 parts by weight of the pigment, the adhesive effect as a binder will not be obtained, and if it exceeds 40 parts by weight, the viscosity of the coating composition will increase, making handling difficult. The properties and coatability are significantly reduced.
Undesirable. Additives commonly used in the paper coating composition of the present invention, such as fillers, water-retaining agents, anti-aging agents, water-resistant agents, antifoaming agents, and mold release agents, to the extent that they do not impair the performance aimed at by the present invention. can contain. The components of the present invention are mixed and prepared according to a conventional method and applied to a paper substrate using a conventional coating method such as an air knife coater, a blade coater, or a roll coater. As described above, the paper coating composition of the present invention has a number of advantages listed below. () The pigment has excellent dispersion stability and is difficult to separate. () Since the composition is uniform, coated paper with stable performance and good quality can be obtained. () Good coating properties due to uniform composition. () Compared to coating composition liquids using conventional dispersants, the viscosity is lower and the pigment dispersion stability is excellent. () Excellent coating properties at high speed coating, and good appearance and performance of the coating layer. () Suitable for high solidity differentiation, and particularly superior in coating workability compared to conventional high solidity paper coating compositions. Moreover, coated paper with stable quality can be obtained. High solidity fractionation of paper coating compositions has great effects in terms of coating productivity, such as speeding up coating, shortening drying time, improving productivity, and saving energy. () Excellent water resistance. EXAMPLES The present invention will be explained in more detail by showing Examples and Comparative Examples below. Note that % and parts in Examples and Comparative Examples are weight % and parts by weight, respectively. Reference Examples 1 to 15 Reference Example of Dispersant Manufacturing Method 1 Capacity 1 equipped with a reflux condenser and a stirring device
Put 400 g of n-hexane and 4 g of boron trifluoride/phenol complex into a three-necked flask and bring to a temperature of 50.
After raising the temperature to ℃, 140 g of dicyclopentadiene with a purity of 95% was added dropwise over about 1 hour while stirring.
The reaction was further continued at this temperature for 2 hours. After the reaction was completed, the catalyst was decomposed with an aqueous sodium carbonate solution and washed with water, and then the oil layer was distilled under reduced pressure to remove n-hexane and unreacted dicyclopentadiene. The weight of the obtained residue was 78 g, and the number average molecular weight of this residue was 2100. Further, when the remaining double bonds in the residue were determined by iodometric titration, it was found that 0.83 equivalents of double bonds remained per mole of reacted dicyclopentadiene. Next, capacity 1 is equipped with a stirring device and a thermometer.
The above residue in a stainless steel autoclave of 20
g, toluene 30g, sodium bisulfite 20g,
Potassium nitrate 2g, isopropyl alcohol 300g
ml and 50 g of distilled water, and air was supplied at room temperature until the internal pressure in the autoclave reached 1.0 Kg/cm ² (gauge pressure), then the valve was sealed and the autoclave was heated to 110°C for 5 minutes while mixing under strong stirring. The reaction was allowed to take place over a period of time. After that, let it cool to room temperature, remove most of the isopropyl alcohol by distillation, and then distilled water 1
Add 1.5% of petroleum ether and mix well.
The aqueous layer obtained by removing the separated petroleum ether layer and precipitate was concentrated and evaporated to dryness. This was dissolved in glacial acetic acid, and the acetic acid insoluble portion consisting of inorganic salts was separated. By concentrating the obtained acetic acid soluble portion, 18.7 g of a white-yellow solid was obtained. This will be referred to as "Sample 1". Reference Example 2 The same procedure as in Reference Example 1 was carried out except that cyclopentadiene was used instead of dicyclopentadiene and the reaction was carried out at a temperature of 30°C to obtain 68 g of a residue. The number average molecular weight of this residue was 5,600. Further, when the remaining double bonds in this residue were quantified in the same manner as in Reference Example 1, it was found that 0.90 equivalents of double bonds remained with respect to 1 mole of reacted cyclopentadiene. Next, sulfonation treatment was carried out in the same manner as in Reference Example 1 to obtain 14.3 g of a white-yellow solid. This will be referred to as "Sample 2." Reference example 3 Capacity 3 equipped with a reflux condenser and a stirring device
Put 1270 g of toluene and 12 g of boron trifluoride/phenol complex into a three-necked flask, raise the temperature to 50°C, and add dicyclopentadiene while stirring.
A mixed solution of 417 g and 320 g of toluene was added dropwise over about 1 hour, and the reaction was further continued at this temperature for 2 hours. After the reaction was completed, the catalyst was decomposed with a sodium carbonate solution and washed with water, and then the oil layer was distilled under reduced pressure to remove 1360 g of unreacted toluene and 35 g of dicyclopentadiene, yielding 601 g of a residue.
When the remaining double bonds in this residue were examined by iodometric titration, it was found that 0.96 equivalents of double bonds remained per mole of reacted dicyclopentadiene. In addition, when the molecular weight distribution of the residue was examined by GPC (gel permeation chromatography), the lower limit of the molecular weight was 224 for a compound (approximately 63% by weight) in which 1 mol of toluene was added to 1 mol of dicyclopentadiene. Polystyrene equivalent molecular weight 8000
There were compounds with various molecular weights up to . Next, capacity 3 is equipped with a stirring device and a thermometer.
Said residue in stainless steel autoclave
20 g, sodium bisulfite, 20 g of potassium nitrate, 300 ml of isopropyl alcohol, and 50 g of distilled water, and the internal pressure in the autoclave was adjusted at room temperature.
After supplying air until the pressure reached 1.0 Kg/cm ² (gauge pressure), the valve was sealed, and the mixture was reacted at a temperature of 110° C. for 3 hours with vigorous stirring. After that, it was allowed to cool to room temperature, and after removing most of the isopropyl alcohol by distillation, 1 part of distilled water and 1.5 parts of petroleum ether were added and thoroughly mixed, and the separated petroleum ether layer and precipitate were removed to obtain the aqueous layer. Concentrate and evaporate to dryness. This was dissolved in glacial acetic acid, and the acetic acid insoluble portion consisting of inorganic salts was separated. By concentrating the obtained acetic acid soluble portion, 25.8 g of a yellow solid was obtained. This will be referred to as "Sample 3." Reference Example 4 In Reference Example 3, the toluene initially charged
1590 g of unreacted ethylbenzene and 52 g of cyclopentadiene were reacted in the same manner as in Reference Example 3, except that 1510 g of ethylenebenzene was used instead of 1270 g, and 320 g of ethylbenzene was used instead of 320 g of dropped toluene.
was distilled off to obtain 588 g of residue. When the remaining double bonds in this residue were examined by iodometric titration, it was found that 0.95 equivalents of double bonds remained per mole of reacted dicyclopentadiene. In addition, when the molecular weight distribution of the residue was investigated in the same manner as in Reference Example 3, the lower limit was the molecular weight of 238 for a compound in which 1 mole of ethylbenzene was added to 1 mole of dicyclopentadiene (approximately 58% by weight), and a compound with a polystyrene equivalent molecular weight of 11,000. Compounds with various molecular weights existed up to . Next, sulfonation treatment was performed in the same manner as in Reference Example 3 to obtain 23.8 g of a yellow solid. This will be referred to as "Sample 4." Reference Example 5 Sample 3 obtained in Reference Example 3 was placed in a 3-neck flask with a capacity of 0.2 and equipped with a stirrer and a thermometer.
mmol, formaldehyde 30 mmol, sulfuric acid 30
mmol and 270 mmol of distilled water were charged, and a condensation reaction was carried out at a temperature of 80°C for 24 hours. After adding 100 g of distilled water to the obtained reaction product, calcium carbonate was added with stirring until the pH reached 7, and then the obtained mixture was filtered to obtain a liquid. Further, soda carbonate was added to this liquid while stirring until the pH reached 9, and then filtered to obtain a liquid. This liquid was dried to obtain 11.6 g of brown powder. This will be referred to as "Sample 5." When the molecular weight distribution of this sample 5 was measured by aqueous GPC (gel permeation chromatography), it was found that compounds with a molecular weight of 500 or less
% or less, and a large peak occurred at a molecular weight of 4300. Reference example 6 Capacity 3 comprising a reflux condenser and a stirring device
Put 1270 g of toluene and 12 g of boron trifluoride/phenol complex into a three-necked flask, raise the temperature to 50°C, and add dicyclopentadiene while stirring.
A mixed solution of 417 g and 320 g of toluene was added dropwise over about 1 hour, and the reaction was further continued at this temperature for 2 hours. After the reaction was completed, the catalyst was decomposed with an aqueous sodium carbonate solution and washed with water, and the oil layer was distilled under reduced pressure to obtain 423 g of toluene adduct of dicyclopentadiene. Next, capacity 3 is equipped with a stirring device and a thermometer.
200 g of the toluene adduct of dicyclopentadiene, 97.8 g of sodium bisulfite, 8.0 g of potassium nitrate, 1360 ml of isopropyl alcohol, and 200 ml of distilled water were placed in a stainless steel autoclave, and the internal pressure in the autoclave was adjusted to 1.0 kg/kg at room temperature.
After supplying air to cm ² (gauge pressure), close the valve and adjust the temperature while stirring vigorously.
The reaction was carried out at 110°C for 5 hours. Then, after cooling to room temperature, the reaction mixture was taken out, 50 ml of distilled water and 1,500 ml of petroleum ether were added, and mixed thoroughly. The separated petroleum ether layer and the precipitate were removed, and the remainder was concentrated and distilled to dryness to give 139 g of pale yellow powder. was gotten. This powder was extracted with petroleum ether for 1 hour using a Soxhlet extractor to remove the reactants, and the remaining liquid was dried and dissolved in 300 ml of glacial acetic acid to separate the acetic acid insoluble portion consisting of inorganic salts. By concentrating the obtained acetic acid soluble portion, 129 g of a white-yellow solid was obtained. This solid was purified by ethanol extraction to obtain the sodium salt of the sulfonated toluene adduct of dicyclopentadiene. Capacity 0.2, then equipped with a stirring device and a thermometer
30 mmol of the above sodium salt, 30 mmol of formaldehyde, 30 mmol of acetic acid, and 270 mmol of distilled water were placed in a three-necked flask, and the temperature was 80°C.
The condensation reaction was carried out at ℃ for 24 hours. After adding 100 g of distilled water to the obtained reaction product, calcium carbonate was added with stirring until the pH reached 7, and then the obtained mixture was filtered to obtain a liquid. Sodium carbonate was added to this solution with stirring until the pH reached 9, and then filtered to obtain a solution. This liquid was dried to obtain 11.2 g of brown powder. This will be referred to as "Sample 6". When the molecular weight was measured by aqueous GPC (gel permeation chromatography), the number average molecular weight was 4900. Reference example 7 In reference example 6, xylene was used instead of toluene.
Using 1060g, this and 350g of dicyclopentadiene
g was reacted in the same manner as in Reference Example 6 to obtain 340 g of a xylene adduct of dicyclopentadiene. 124 g of the sodium salt of the sulfonated xylene adduct of dicyclopentadiene was obtained in the same manner as in Reference Example 6, except that 200 g of this xylene adduct was used. This will be referred to as "sample 7." Next, using this sodium salt, a condensation reaction was carried out in the same manner as in Reference Example 6 to obtain 10.3 g of brown powder.
In addition, when the molecular weight was measured by aqueous GPC,
The number average molecular weight was 5,400. Reference Example 8 3000 g of dicyclopentadiene, 1888 g of sodium bisulfite, 91.7 g of potassium nitrate, 12 g of isopropyl alcohol, and 3000 g of distilled water were placed in a stainless steel autoclave with a capacity of 30 and equipped with a stirring device and a thermometer, and the mixture was heated in the autoclave at room temperature. After nitrogen was supplied until the internal pressure reached 1.0 Kg/cm ² (gauge pressure), the valve was sealed and the reaction was carried out at 110° C. for 5 hours while mixing under strong stirring.
After that, it was left to cool to room temperature, most of the isopropyl alcohol was removed by distillation, then distilled water and petroleum ether were added and thoroughly mixed, the separated petroleum ether layer and precipitate were removed, and the resulting aqueous layer was concentrated. , distilled to dryness. Dissolve this in glacial acetic acid,
The acetic acid-insoluble portion consisting of inorganic salts was separated using a centrifuge. By concentrating the obtained acetic acid soluble content, 2800 g of white solid was obtained (this was converted into sulfonated compound A).

[Formula]). After this aqueous solution of sulfonated compound A was exchanged into the acid form using an ion exchange resin, the water was concentrated to dryness to obtain the acid form of the sulfonated compound (this was converted into the acid form of sulfonated compound B).

[Formula]). Next, 15 g of the sulfonated compound B and 6.88 g of sulfuric acid were placed in a 300 ml three-necked flask equipped with a reflux condenser and a stirring device, and the mixture was heated at 120°C.
The polymerization reaction was carried out for 26 hours. After the reaction was completed, liming with calcium carbonate and sodation with sodium carbonate were performed, and the solid content obtained was 15.5 g, and the number average molecular weight of this polymer was 10,000. This will be referred to as "Sample 8." Reference Example 9 In Reference Example 8, except that sulfonated compound A was used, the same treatment was carried out, and the number average molecular weight of the polymer was 1600.
I got something. This will be referred to as "Sample 9." Reference Example 10 In Reference Example 8, the polymerization reaction was performed using a sulfonated product.
Using 30g of A, add 125g of sulfuric acid and 11.4g of water, and
A polymer having a number average molecular weight of 8,000 was obtained by performing the same treatment except that the reaction was carried out at 170°C for 28 hours, and this was designated as "Sample 10". Reference example 11 Capacity with reflux condenser and stirring device
13g of sulfonated compound A in a 300ml three-neck flask,
Add 2g of dicyclopentadiene and 6.88g of sulfuric acid,
A copolymerization reaction was carried out at a temperature of 120°C for 20 hours.
After the reaction, liming was performed using calcium carbonate and sodation was performed using sodium carbonate, and the solid content obtained was 15.0 g. This will be referred to as "Sample 11." Reference example 12 300ml capacity with reflux condenser and stirring device
In a three-neck flask, a sulfonated product of hydroxydicyclopentadiene (in the general formula (f) above, M
=H compound) and 6.88 g of sulfuric acid were added and polymerized at a temperature of 120°C for 23 hours. After the reaction was completed, liming was performed using calcium carbonate (SO ₃ was removed and M=H became M=Ca), and sodation was performed using sodium carbonate (M=Ca became M=Na). , the solid material obtained was 15.5 g, and the number average molecular weight of this polymer was
It was 10,000. This will be referred to as "Sample 12." Reference example 13 Capacity 300ml with reflux condenser and stirring device
In a three-neck flask, a sulfonated product of hydroxydicyclopentadiene (in the general formula (f) above, M
8 g of a compound in which =H) and a sulfonated product of dicyclopentadiene (structural formula:

[Formula]) and 6.88 g of sulfuric acid were added and polymerized at a temperature of 120°C for 23 hours.
After the reaction, liming and sodation were performed in the same manner as in Reference Example 12, and the solid content obtained was 15.5 g.
It was hot. This will be referred to as "Sample 13." Reference example 14 300ml capacity with reflux condenser and stirring device
In a three-neck flask, a sulfonated product of hydroxydicyclopentadiene (in the general formula (f) above, M
=H compound), 2 g of acrylic acid, and 6.88 g of sulfuric acid were added, and a copolymerization reaction was carried out at a temperature of 120° C. for 2 hours. After the reaction, liming and sodation were performed in the same manner as in Reference Example 12, and the solid content obtained was 15.4 g. This will be referred to as "Sample 14." Reference example 15 Capacity 3 comprising a reflux condenser and a stirring device
Put 1270 g of toluene and 12 g of boron trifluoride/phenol complex into a three-necked flask and bring to a temperature of 50°C.
After raising the temperature to , a mixed solution of 417 g of dicyclopentadiene and 320 g of toluene was added dropwise over about 1 hour while stirring, and the reaction was further continued at this temperature for 2 hours. After the reaction was completed, the catalyst was decomposed with an aqueous sodium carbonate solution and washed with water, and the oil layer was distilled under reduced pressure to obtain 423 g of toluene adduct of dicyclopentadiene. Next, capacity 3 is equipped with a stirring device and a thermometer.
200 g of the toluene adduct of dicyclopentadiene, 97.8 g of sodium bisulfite, 8.0 g of potassium sulfate, 1360 ml of isopropyl alcohol, and 200 ml of distilled water were placed in a stainless steel autoclave, and the internal pressure of the autoclave was 1.0 Kg/cm ² at room temperature.
After supplying air until the pressure reaches (gauge pressure), close the valve and mix under strong stirring until the temperature reaches 110.
The reaction was carried out at ℃ for 5 hours. Then, after cooling to room temperature, the reaction mixture was taken out, 50 ml of distilled water and 1,500 ml of petroleum ether were added, and mixed thoroughly. After removing the separated petroleum ether layer and precipitate, the remainder was concentrated and evaporated to dryness to give 139 g of pale yellow powder. was gotten.
This powder was extracted with petroleum ether for 1 hour to remove unreacted substances using a Soxhlet extractor, and the remaining liquid was dried and dissolved in 300 ml of glacial acid to separate acetic acid insoluble components consisting of inorganic salts. By concentrating the obtained acetic acid soluble portion, 129 g of a white-yellow solid was obtained. This solid was purified by ethanol extraction to obtain the sodium salt of the sulfonated dicyclopentadiene-toluene adduct. The sodium salt of the sulfonated dicyclopentadiene-toluene adduct is designated as product A'. Next, the capacity is equipped with a stirring device and a thermometer.
60 mmol of the above product A' and 80 mmol of sulfuric acid were placed in a 0.2 mm three-necked flask and reacted at a temperature of 100° C. for 3 hours. Thereafter, the reaction was carried out at a temperature of 110℃ for 2 hours, and then 10ml of n-heptane was added.
was added and further heated under reduced pressure at a temperature of 80°C.
Heptane and water were removed azeotropically. The product obtained by this reaction is designated as B'. Next, 6.3 g of water was added to this product B′, and the temperature was 80°C.
5.35 g of 37% formaldehyde aqueous solution (66
mmol) was added dropwise over 3 hours, and then
When the temperature was raised to 100℃ and the condensation reaction was carried out for 20 hours,
A viscous reaction product was obtained. This is called product C'. After adding 100 g of water to this product C′ and dissolving it,
Add 11g of calcium carbonate to bring the solution to pH 7,
Separate the formed white precipitate, add 3.2 g of sodium carbonate to the liquid, and separate the formed white precipitate. Then, the obtained liquid was dried to solidify, and this was called “sample”.
15". The number average molecular weight of this sample was 6300 as measured by GPC. Test Methods Used in Examples and Comparative Examples (2) Method for Measuring Viscosity of Coating Composition Liquid Viscosity was measured using a B-type viscometer at 25° C. and a 60 rpm No. 3 rotor. () Apparent viscosity measurement method for high-speed fluidity Using a Hercules high shear viscometer manufactured by Riki Kumagaya, rotation speed 8800 r.pm, Bob F torque range 2
Calculate from the following formula using Tmax (dyne.cm) measured under the following conditions. Apparent viscosity = 9.55×8×10 ^-5 ×Tmax880×
100 This is an indicator of coatability in high-speed coating, and the higher the value, the worse the coatability tends to be. () High-speed coating property and coating layer property evaluation method Using a high-speed single-fed blade coater manufactured by Riki Kumagaya, speed of 300 m/min, blade contact angle of 30°,
The coating composition liquid was applied to a paper substrate under the condition of an air pressure of 1.5 Kg/cm ² , and the ease of application and the surface quality of the coated paper were visually evaluated and judged according to the following evaluation criteria. ○ (Good) △ (Slightly poor) × (Poor) () Mechanical stability measurement method Using a Marlon stability tester,
Measurement was performed at 1000 rpm, pressure 10 kg, time 10 minutes, and coating composition liquid temperature 70°C. This is an index of the dispersion stability of the pigment, and the larger the value, the poorer the dispersion stability. () Water resistance strength test of coated paper A coating composition liquid was applied to a paper substrate using a high-speed single-fed blade coater manufactured by Kumagaya Riki Co., Ltd. to obtain coated paper. Next, use a hot air dryer at a temperature of 120℃ for a period of time.
The coated paper was dried for 30 seconds and then dried using a super calender at a roll temperature of 70°C and a rotation speed of 450 r.p.
Finishing was carried out with a linear pressure of 70 Kg/cm and two passes of paper. The obtained coated paper was manufactured by Mei Seisakusho R-
Toyo Ink SMX TV using a mold printing machine = 15
Printed using ink. Coated paper was evaluated using the following evaluation criteria. ○ (Good) No picking occurred △ (Slightly poor) A small amount of picking occurred × (Poor) A large amount of picking occurred Examples 1 to 2, Comparative Examples 1 to 4 The solid content concentration of the coating composition was the concentration shown in Table 1. Prepare water in advance in a container equipped with a Coles disperser so that Stir for 10 minutes,
Add 30 parts of heavy calcium carbonate in the same way and add 2000 r.p.
Stir for 10 minutes at m. Subsequently, 5 parts of starch were added, and after stirring for 10 minutes, 12 parts of a carboxy-modified styrene-butadiene copolymer was further added and stirred at 2000 rpm to prepare a coating composition. Using this coating composition, the dispersion stability, high-speed coating properties, and coating layer performance of the coating composition, which are the objectives of the present invention, were evaluated using the test methods shown above. are summarized in Table 1. Examples 1 to 15 are examples in which the dispersant of the present invention was used with a compound that essentially contains a tricyclodecane or tricyclodecene skeleton and a sulfonic acid group in the molecule, and was used for paper coating as the object of the present invention. A composition was obtained. Examples 20 to 22 are examples in which Sample 9 was used as a dispersant, but the amount used was varied, and paper coating compositions aimed at the present invention were also obtained. Example 20 uses a high condensate of naphthalene sulfonate as a dispersant, Example 21 uses a condensate of triazine sulfonate as a dispersant, Example 22
Examples are examples in which sodium ligninsulfonate was used as a dispersant, and in each example, the paper coating composition targeted by the present invention was obtained. Comparative Examples 1 to 3 are examples in which dispersants conventionally used in paper coating compositions were used. Compared to the paper coating composition using the dispersant of the present invention, () the dispersion stability is poor despite the large amount of dispersant used, () the viscosity is high and it is difficult to handle, and () the high-speed apparent viscosity is high. Poor high-speed coating properties,
Actual high-speed coating shows a similar tendency; () It can be seen that the appearance and water resistance of the coated layer coated at high speed are poor and undesirable. Comparative Example 4 is an example in which the dispersant of the present invention was used beyond the scope of the present invention, which is not preferred because the viscosity increases and the coating properties at high speed coating are poor.

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Claims (1)

[Scope of Claims] 1 Based on 100 parts by weight of pigment (A) High condensate of naphthalene sulfonate, condensate of alkylaryl sulfonate, condensate of triazine sulfonate, condensate of anthracene sulfonate , lignin sulfonate, a cocondensate of lignin and naphthalene sulfonate, and at least one dispersant selected from the group of compounds that essentially contain a tricyclodecane or tricyclodecene skeleton and a sulfonic acid group in the molecule.
A paper coating composition characterized in that it contains 0.005 to 5 parts by weight (B) and 1 to 40 parts by weight of a pigment binder.