JPH0150267B2 - - Google Patents

Description

[Detailed description of the invention]

This invention relates generally to improved printing ink compositions and methods of making the same, and more particularly to printing inks suitable for high speed printing operations. The production of materials suitable for printing inks by dispersing finely divided pigments, ie ink colorants, in organic ink vehicles is a highly complex technique. The type of surface being printed on, the specific printing press used, operating speed and drying time all depend on
It is the fundamental factor that determines the working characteristics required for a satisfactory ink. As the circulation of modern newspapers greatly expanded, high-speed presses were developed and used in the printing industry. This required printing inks that set rapidly. Resin systems that can be dried by water, steam or hot air are increasingly replacing the previously used drying oils. Modern high-speed presses require ink to set in seconds rather than minutes. For high speed printing, inks must maintain the proper balance of tack, penetration and flow control. If the tack is too high, the paper will tear or the ink will blur at high press speeds. Inks with insufficient tack will not transfer properly during printing runs. If the ink is too penetrating, the print will show through the back side of the paper or the picture will become unclear.
The permeability is poorly controlled, causing smearing even after the ink is thought to be fixed. The ink must have flow properties to prevent centrifugation at high press speeds. On the other hand, if the viscosity is too high, it will not flow properly from the ink dispenser to the rollers. These factors and conditions required are such that the ink industry has to rely on a large number of compositions. For example, U.S. Pat. No. 2,750,296 contains a colorant dispersed in a vehicle consisting of an oil-soluble resin binder dissolved in mineral oil;
and a long-chain aliphatic amine bentonite having 34 carbon atoms in the aliphatic chain. In contrast, U.S. patent no.
No. 2754219 discloses a blur-proofing ink prepared by adding a finely divided organic component of montmorillonite containing a chain of at least 12 carbon atoms to an ink in which the main vehicle component is a hydrocarbon containing an aromatic component. Printing ink compositions are disclosed. In addition to these U.S. patents, additional U.S. patents no.
No. 2,739,067 discloses a printing ink containing a modified clay that forms a gel in an organic vehicle and exhibits substantial gel properties therein. However, all conventional compounds have various drawbacks. For example, some require the use of undesirable organic dispersing additives that react with other ink composition components and eliminate essential ink properties; others increase viscosity during storage. It is necessary to apply a lot of shear through the roll kneader in order to obtain a raw material of stable viscosity that is labor intensive and does not involve production stoppages. In marked contrast to these prior art applications, U.S. Pat. A method for producing a shelf-stable printing ink comprising an organic ink vehicle and an organophilic clay gelling agent comprising a reaction product with a methylbenzylalkylammonium compound or a dibenzyldialkyl ammonium compound is disclosed. This U.S. patented printing ink differs significantly from conventional viscosity-increasing control gelling agents;
It is stated that sufficient viscosity can be obtained by passing through a three-roll kneader once. Although the printing ink of this patent raises the state of the art to a new level, further advances and improvements need to be made such that initial high shear effects do not have to be exerted to obtain acceptable viscosity levels. In view of the above, according to the present invention, a reaction product of a smectite-type clay having a cation exchange capacity of at least 75 milliequivalents per 100 g of viscosity and a methyltrialkyl quaternary compound or a benzyltrialkyl quaternary compound [however, The quaternary compound is ammonium or phosphonium,
the alkyl group contains 12 to 22 carbon atoms,
The amount of the quaternary compound to be reacted with the clay is
A printing ink composition comprising an organic ink vehicle in which an organophilic clay gelling agent (100 to 130 milliequivalents per 100 g of clay on a 100% active clay basis) and an ink coloring substance are dispersed. is provided. The clay used to make the organophilic clay gelling agent of this invention is a smectite type clay having a cation exchange capacity of at least 75 milliequivalents per 100 grams of clay. Particularly desirable types of clays are clays such as naturally occurring Wyoming species swellable bentonite and hectorite or swellable magnesium-lithium silicate clays. Clays, especially bentonite type clays, are preferably converted to the sodium form if they are not already in the sodium form. This can be conveniently accomplished by making an aqueous clay slurry and passing this slurry through a bed of cation exchange resin in the sodium form. Alternatively, the clay can be mixed with water and soluble sodium compounds such as sodium carbonate, sodium hydroxide, etc. and the mixture sheared in a kneader or extruder. The organophilic clays of this invention can also be prepared using synthetic or natural smectite type clays, either by pneumatic or preferably by hydrothermal synthesis. Representative examples of such clays are montmorillonite, bentonite, beidellite, hectorite, saponite and steppensite. These clays contain mixed aqueous oxides or hydroxides of the desired metals, optionally with or without sodium fluoride (or an alternative mixture of exchangeable cations), in the desired ratio of specific synthetic smectites. It can be synthesized hydrothermally by forming an aqueous reaction mixture in the form of a slurry. Put this slurry into an autoclave and under autogenous pressure about 100-325
C., preferably in the range of 274 DEG to 300 DEG C., for a sufficient period of time to form the desired product. The cation exchange capacity of smectite clay can be measured by the well-known ammonium acetate method. A quaternary compound reacted with smectite clay,
Namely, ammonium compounds and phosphonium compounds include methyltrialkylammonium salts, methyltrialkylphosphonium salts, benzyltrialkylammonium salts, benzyltrialkylphosphonium salts and mixtures thereof (the alkyl group of which is a straight alkyl group containing 12 to 22 carbon atoms). chain or branched alkyl group selected from the group consisting of saturated or unsaturated and mixtures thereof. Preferably the alkyl groups contain 16-18 carbon atoms, and most preferably 20-35% of the alkyl groups contain 16 carbon atoms and 60-75% contain 18 carbon atoms. It contains. The salt anion is preferably selected from the group consisting of chloride ions, bromide ions, and mixed ions thereof, and more preferably chloride ions. However, other anions such as acetate, hydroxide, nitrite, etc. can also neutralize quaternary cations. These quaternary salts have the formula [Wherein, X is nitrogen or phosphorus, and R ₁ is CH ₃
or _{C6H5CH2 and R2} , _R3 and _{R4 are} 12~
is a long chain alkyl group having 22 carbon atoms,
M ^- is chlorine, bromine, nitrite, hydroxyl, acetic acid,
selected from the group consisting of each ion of methyl sulfate and mixtures thereof]. Long chain alkyl groups can be derived from various natural vegetable oils such as corn oil, coconut oil, soybean oil, cottonseed oil, and castor oil, and various animal fats and oils such as beef tallow. They can also be derived from petrochemicals such as alkyl groups or alpha-olefins. It should be added that representative alkyl groups are stearin and oleyl groups. Preferred quaternary ammonia salts are benzyl trihydride talloammonium chloride and methyl trihydride talloammonium chloride. Industrially produced hydrogenated taro typically contains 2.0% _C14 , 0.5
% _C15 , 20.0% _C16 , 1.5% _C17 , 66.0% _C18 and 1.0
It has an analysis value of % C ₂₀ alkyl groups. The organophilic clay of the present invention can be prepared by mixing clay, an organic quaternary compound, and water for a sufficient period of time, preferably at a temperature in the range of 20 to 80°C, particularly preferably in the range of 65 to 75°C. It can be produced by coating with a quaternary compound, followed by filtering, washing, drying and grinding. When using organophilic clay in the form of an emulsion, the drying and milling steps can be omitted. The filtering and washing steps can be omitted if the clay, quaternary compound, and water are mixed at concentrations that do not form a slurry. The clay is dispersed in water at a concentration of about 1-80%, preferably 2-7% by weight, and the slurry is optionally centrifuged to remove non-clay impurities, which constitute about 10-15% by weight of the starting clay composition. It is preferable to do so. The slurry is stirred and heated to a temperature ranging from 140°C (60°C) to 170°C (77°C), and the quaternary ammonium salt or quaternary phosphonium salt is added in the desired milliequivalent ratio, preferably in isopropanol or water. Add as a dispersion and continue stirring to allow reaction to occur. The amount of quaternary compound added to the clay for purposes of this invention must be sufficient to impart the desired enhanced dispersion properties to the clay. The milliequivalent ratio is
It is defined as the number of milliequivalents of quaternary compounds in the organophilic clay per 100 grams of clay on a 100% active basis.
The organophilic clay of the present invention has a meliquivalent ratio of 100 to 130. At lower milliequivalent ratios, organophilic clays are ineffective gelling agents even though they can be effective gelling agents when dispersed with polar additives by conventional methods. At higher milliequivalent ratios, organophilic clays are poor gelling agents. However, suitable milliequivalent ratios within the range of 100-130 will vary depending on the properties of the organic system to be gelled by the organophilic clay. Printing inks are produced economically and practically by simply incorporating an organophilic clay gelling agent into a base ink composition containing an ink colorant and an organic ink vehicle. The ink compositions of the present invention achieve high clay levels with simple stirring during ink preparation, without the need for passing through a three-roll mill or using other similar methods to enhance clay. It can be easily dispersed when used as a rheology additive and, in the absence of a three-roll mill, can be passed through a conventional dispersion machine to obtain a product with the highest viscosity structure. The ink composition in which the organophilic clay of the present invention is appropriately dispersed has sufficiently fine particles and can be used immediately without the need for filtering or grinding. The use of a three roll mill is generally required to aid in the dispersion of the ink coloring pigments or ingredients to ensure sufficient ink coverage on the press, but is not required for clay buildup. In the case of an ink system in which hard small particles are produced unless air is entrained during dispersion to cause oxidation, it may be necessary to pass the ink through a gentle three-roll kneader. The invention can also be carried out by adding an organophilic clay gelling agent to a pre-prepared finished printing ink. These inks can be prepared by any conventional method that provides good dispersion of the ink pigments in the organic ink vehicle due to the high shear used in processing such as colloid mills, roller mills, ball mills, etc. This dispersion of pigment in the vehicle constitutes a conventional ink and exhibits a conventional tendency to blur. The organophilic clay gelling agent is used in an amount sufficient to obtain the desired clay value and tack in the printing ink. If desired, the viscosity can be further adjusted by adding viscosity reducing agents, such as naphthenic oils or solvents. Generally, when used in high-speed press printing operations, 0.1~
An amount of 10% by weight is sufficient, but a preferred amount is 0.5-
4% by weight, most preferably 1-3% by weight.
Gelling agent less than 0.1% by weight of printing ink,
Or, if used in a concentration greater than 10% by weight, properties such as consistency and fluidity, which affect the critical properties of the ink, are significantly impaired. That is, the desired increase in viscosity and stickiness is not achieved. The printing inks of the invention can contain the customary ink additives used in printing inks of this type. For example, oil-soluble toning agents used to suppress the browning of mineral oils and carbon black pigments can be used as well as small amounts of waxes or greases to impart special properties to printing inks. Printing inks that can be used with the gelling agents of the present invention include, but are not limited to, for example thermosetting or newsprint inks, water or steam fixed inks or lithographic inks. Newsprint ink dries primarily by penetration and absorption, but some heat is applied to accelerate drying and prevent smearing. By suitably adjusting the viscosity, tack and yield point for this type of ink, the organophilic clay of the present invention effectively achieves proper penetration without centrifugation or blurring. When the organophilic clay of the present invention is used in thermosetting type printing inks, such as premium inks for periodicals, containing additives such as binders and solvents, the inks become extremely elastic;
Prints well without smearing, and fixes quickly at high temperatures. The use of gelling agents in water vapor or water fixed inks imparts a characteristic shortness to the ink and significantly affects viscosity and tack. Lithographic inks, on the other hand, are very similar in composition to type printing inks, except for a slightly higher viscosity and higher pigment concentration. In this case too, the benefits of using organophilic clays as indicated above are obtained. EXAMPLES This invention will be described below with reference to Examples, but the invention is not limited to these Examples. All percentages shown in this specification are weight percentages unless otherwise specified. In the examples, the following test method was used: Dispersion The test ink was poured into both grooves of an NPIRI G-1 attrition meter and then examined for grind size and scratch. The instrument scale goes from 10 to 0. 10 is 1 mil (1 inch/
1000), and 0 is depth 0. Samples are drawn and measured a minimum of four times and averaged. A clean reading for the sample should be "0" for both grind size and scratch. Viscosity Viscosity was measured using a Swing-Albert falling rod viscometer at a closure temperature of 78〓 (25.6°C). The air was removed by a simple spatula spreading method, and the rod was then completely covered with the sample ink. Three weights were used to measure the fall time: 700, 500, and 200 g.
These weights are repeated and the data is
The expected Bingham viscosity at 1000 sec ^-1 poise was obtained by the Parkard computer. The viscosity values chosen for each table are determined by the Bingham formula f _B = T - D _B M _B (where f _B is the yield value, T is the shear stress, D _B is the shear rate, and M _B is the viscosity. ) is obtained using data containing the minimum value of the root of the mean squared deviation from the straight line, i.e., the value corresponding to the intercept on the shear stress axis when the shear rate is 0. It is. Example 1 A heatset blue base ink formulation for an offset rotary press was prepared with the ingredients shown in Table A and passed through a three roll mill to obtain a fine ink dispersion. The rheology additive was slowly added to the base ink with minimal agitation to avoid spillage. Dispersion was performed at 300 rpm using a 0.5 horsepower premier disperser unit with Cowles blades. Proper speed was maintained for 15 minutes. Viscosity measurement is further performed during dispersion.
I went 24 hours later and a week later. Each sample ink was treated with different organophilic clay derivatives and comparison materials at a level of 2% by weight. Comparative Test A did not use rheology additives, and Comparative Test B used the same silica particles as the product Aerosil R.972 (manufactured by De Gusa Company). Tests 1 to 3 according to the present invention used a product obtained by reacting Wyoming bentonite with methyl trihydride talloammonium chloride and benzyl trihydride talloammonium chloride in the indicated milliequivalent ratios. The results are shown in Table 1. The results show that compared to the formulation of the present invention, the comparative test rheology additive has poorer particle size grinding and lower gelling efficiency.

[Table] * Dior is a subsidiary of Lauda Chemical.

[Table] Example 2 A heatset red base ink formulation for an offset rotary press was prepared with the ingredients shown in Table B,
Then, a fine ink dispersion was obtained through a three-roll kneading machine. The indicated amount of rheology additive was added and dispersed for 5 minutes by simple mixing with a spatula. The results are shown in Table 2. The quaternary compound was prepared as described in Example 3. Comparative Test C is an example in which no rheology additive is used, and Comparative Test D is an example in which, like Comparative Test B, fine silica powder is used. Comparative Test E is an example in which the rheology additive described in US Pat. No. 4,193,806, ie, methylbenzyl dihydrogenated taloammonium bentonite containing 112 milliequivalents, was used. According to the data presented in Table 2, the rheology additive of the present invention using the quaternary compound of the present invention achieves good dispersion and efficiency at low mixing conditions without excessively increasing viscosity. It was done.

[Table] * Dior is a subsidiary of Lauda Chemical.

[Table] Example 3 0.5 using the same base ink as in Table B and adding rheology additives to it and then providing Cowles wings.
1000 ~ using the horsepower premier disperser unit
The treatment was carried out in the same manner as in Example 2 except that the dispersion was carried out under the condition of 3000 rpm. The results are shown in Table 3 (1000 rpm) and Table 4 (3000 rpm). During the test at 3000 rpm, the sample ink was
S.I.G. (gauge pressure, pound/ ^inch2 )
I passed it through a three-roll kneader once underneath. The viscosity at that time was measured, and the measurement was repeated 24 hours later. The results are shown in Table 4.

【table】

Table B Example 4 The method of Example 2 was repeated using the same base ink shown in Table B. Add 294g of base ink to a (friction lid pint can) container without a lid, and add wings to the bottom of the can for laboratory use.
6 g (2%) of additive was added under light shear using a 0.5 horsepower Cowles disperser. When the additives were thoroughly mixed, the mixing speed was set to 3000 rpm, the ink was mixed at 5 minute intervals, and the sampled grinds were tested for particle size and scratches. Temperature and dispersion measurements were taken every 5 minutes. Typical cases in which mixing was stopped were when good dispersion was obtained or when 20 minutes, the critical time for mixing, had elapsed. The control test was mixed for 15 minutes as long as the other samples followed approximately the same course. The results are shown in Table 5. This data shows that comparative feedstocks that provide poor particle size through grinding have difficulty dispersing with high speed mixing and problems with viscosity stability after ink aging. On the contrary, the formulations of the present invention exhibited good particle size for grinding and a highly stable viscosity without the need for passing through a three-roll mill or similar shearing device.

[Table] Although this invention has been explained above, this invention is not limited to these explanations only, and various changes can be made within the scope of the claims without departing from the spirit of this invention. I hope you understand.

Claims (1)

[Scope of Claims] 1. An organophilic clay comprising a reaction product of a smectite-type clay having a cation exchange capacity of at least 75 milliequivalents per 100 g of clay and a methyltrialkyl quaternary compound or a benzyltrialkyl quaternary compound. It consists of an organic ink vehicle in which a gelling agent and an ink coloring substance are dispersed;
The quaternary compound is ammonium or phosphonium, and its alkyl group contains 12 to 22 carbon atoms, and the amount of the quaternary compound to be reacted with the clay is based on 100% active clay and per 100 g of clay.
A printing ink composition characterized in that it has a weight of 100 to 130 milliequivalents. 2. The printing ink composition according to claim 1, wherein the clay is hectorite or sodium bentonite. 3. The printing ink composition according to claim 1 or 2, wherein the alkyl group contains 16 or 18 carbon atoms. 4 Organophilic clay gelling agent is 0.1~
Printing ink composition according to any one of claims 1 to 3, comprising 10% by weight. 5 Organophilic clay gelling agent is 1.0~
Claims 1 to 3 consisting of 3.0% by weight
The printing ink composition according to any one of the above items. 6 The quaternary compound has the formula (wherein, X is nitrogen or phosphorus, and R ₁ is CH ₃
or _{C6H5CH2 and R2} , _R3 and _{R4 are} 12~
is an alkyl group containing 22 carbon atoms, and M ^- is chlorine, bromine, nitrite, hydroxyl,
The printing ink composition according to any one of claims 1 to 5, which is represented by ions of acetic acid, methyl sulfate, and mixtures thereof. 7. The printing ink composition according to claim 6, wherein the organophilic clay is a reaction product of sodium bentonite and methyltrihydrogenated talloammonium chloride or benzyltrihydrogenated talloammonium chloride. 8 Forming a dispersion of an ink colorant and an organic ink vehicle; a smectite-type clay having a cation exchange capacity of at least 75 milliequivalents per 100 g of clay and a methyltrialkyl quaternary compound or a benzyltrialkyl quaternary compound; (However, the quaternary compound consists of ammonium or phosphonium, and its alkyl group is 12
an organophilic clay gelling agent containing ~22 carbon atoms (the amount of said quaternary compound reacted with said clay is 100-130 milliequivalents per 100 g of clay on a 100% active clay basis); A method for producing a printing ink, characterized in that it is mixed with the dispersion to form a mixture; and the mixture is dispersed to form a viscous printing ink. 9. The manufacturing method according to claim 8, wherein the clay is hectorite or sodium bentonite. 10 The organophilic clay gelling agent is 0.1% of the printing ink.
9. The manufacturing method according to claim 8 or 9, comprising ~10% by weight.