JP4067706B2 - Emulsion ink composition for offset printing - Google Patents

Description

【００４３】
【表２】

【００４４】
【発明の効果】
本発明の特定の高級アルコール及び非イオン系界面活性剤、及び特定量の水を含むオフセット印刷用エマルジョンインキ組成物は、網点再現性、着肉性、及び、汚れに対する適性等の基本的な印刷適性を有するとともに、つぼ方式特有のつぼからの垂れ防止、つぼからの吐出性、キーレス方式特有のインキパン内の流動性、ブレード上の流動性を有し、つぼ方式及びキーレス方式のオフ輪印刷機での共用が可能になった。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an emulsion ink composition for offset printing that can be used in both a pot type and a keyless type printing press.
[0002]
[Prior art]
In recent years, machines with different ink supply methods have emerged and used in offset printing. Typical ink supply methods include the pump method (plunger pump method, digital pump method, etc.), jar method, and keyless method. The common use between the pump method and jar method and between the pump method and keyless method is offset. What is possible with ink is a well-known matter.
[0003]
Recently, the printing industry (newspaper companies, etc.) has been focused on simplifying the printing environment and saving labor, and there has been a demand for a new ink composition for offset printing that can be shared between the vase method and the keyless method. Yes. However, the ink composition for offset printing used in the vase method has a relatively low fluidity to prevent dripping from the vase when printing is stopped, while it is used in the keyless method. As the ink composition for offset printing, those having relatively high fluidity are used from the viewpoint of ensuring fluidity in the ink pan and fluidity on the blade. As described above, the offset printing ink compositions used in the pot method and the keyless method are required to have contradictory properties, and thus cannot be shared by both methods.
[0004]
[Problems to be solved by the invention]
The present invention realizes the ink composition for offset printing that can be shared by the pot type and keyless type printing machines in response to the above-mentioned demands, that is, the basics such as halftone dot reproducibility, fillability, and suitability for dirt. Provide an ink composition for offset printing that has a suitable aptitude, satisfies dripping prevention specific to the vase, discharge from the vase, fluidity in the ink pan specific to the keyless method, and fluidity on the blade. This is the issue.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have found that the higher alcohol represented by the following general formula (1) is 0.1 to 5.0% by weight in the total ink composition, and the following general formula ( 2) The nonionic surfactant represented by 2) is contained in the total ink composition in an amount of 0.1 to 3.0% by weight, and the water is included in the total ink composition in an amount of 1 to 15% by weight, thereby shearing. It has been found that the agglomeration rate of the pigment with respect to the speed can be adjusted, thereby satisfying both the suitability peculiar to the vase method and the suitability peculiar to the keyless method, and the present invention has been completed. .
[0006]
That is, the present invention is an emulsion ink composition for offset printing comprising a colorant, a binder resin, a vegetable oil and / or mineral oil, and water as main components. 0.1 to 5.0% by weight of a higher alcohol represented by the formula (1) and 0.1 to 3.0% by weight of a nonionic surfactant represented by the general formula (2), and water It is related with the emulsion ink composition for offset printing characterized by including 1 to 15weight% in all the ink compositions.
[0007]
R ¹ —OH (1)
_{^{R 2 -O- (CH 2 -CH 2}} -O) n-H (2)
(Wherein R ¹ is a saturated hydrocarbon group having 8 to 24 carbon atoms or may contain an unsaturated bond, and R ² is a saturated hydrocarbon group having 4 to 24 carbon atoms, or A hydrocarbon group which may contain an unsaturated bond and / or an aromatic ring, n represents an integer in the range of 1 to 16, and k represents the carbon number of R ² , k and n are 1.5n ≦ k ≦ 6n relationship is satisfied)
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the emulsion ink composition for offset printing of the present invention will be described in detail.
[0009]
In the emulsion ink composition for offset printing of the present invention, 0.1 to 5.0% by weight of the higher alcohol represented by the general formula (1) and the general formula (2) are represented in the total ink composition. The nonionic surfactant is contained in an amount of 0.1 to 3.0% by weight, and the total ink composition contains 1 to 15% by weight of water.
[0010]
The emulsion ink composition for offset printing according to the present invention has the above-mentioned specific composition, so that in the vase method, the ink does not drip from the vase when printing is stopped, and the discharge property from the vase is good at the time of printing. Sometimes it has fluidity in the ink pan and fluidity on the blade, and both can be shared.
[0011]
The higher alcohol used in the emulsion ink composition for offset printing of the present invention is represented by the general formula (1).
[0012]
In the general formula (1), the hydrocarbon group having 8 to 24 carbon atoms represented by R ¹ is a linear or branched saturated aliphatic hydrocarbon group or unsaturated aliphatic hydrocarbon group. can give.
[0013]
Examples of the higher alcohol represented by the general formula (1) include saturated or unsaturated in the range of 8 to 24 carbon atoms such as nonyl alcohol, lauryl alcohol, tridecanol, cetanol, stearyl alcohol, isostearyl alcohol, oleyl alcohol and the like. Monohydric alcohol. These higher alcohols can be used alone or in combination of two or more.
[0014]
The higher alcohol is contained in an amount of 0.1 to 5.0% by weight in the total amount of the emulsion ink composition for offset printing. When the content of the higher alcohol is less than the above range, water separation does not occur sufficiently under a high shear rate such as a nip between rollers of a printing press, resulting in a problem that good printability cannot be obtained. When the content of exceeds the above range, emulsification becomes unstable, and water separation occurs over time.
[0015]
The nonionic surfactant used in the ink composition for offset printing of the present invention is represented by the general formula (2).
[0016]
In the general formula (2), the hydrocarbon group having 4 to 24 carbon atoms represented by R ² is a linear or branched saturated aliphatic hydrocarbon group or unsaturated aliphatic hydrocarbon. Group, or an aromatic hydrocarbon group having a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. If the carbon number of R ^2, the number of n, and the relationship between k and n are out of the above ranges, the desired surface active effect cannot be obtained.
[0017]
Examples of the nonionic surfactant represented by the general formula (2) include polyoxyethylene alkylphenyl ethers such as ethylene oxide polyaddition product of nonylphenol, ethylene oxide polyaddition product of octylphenol, and ethylene oxide of lauryl alcohol. And polyoxyethylene alkyl ethers such as polyaddition products. These nonionic surfactants can be used alone or in combination of two or more.
[0018]
The nonionic surfactant is contained in an amount of 0.1 to 3.0% by weight in the total amount of the emulsion ink composition for offset printing. If the content of the nonionic surfactant is less than the above range, sufficient surface activity cannot be obtained, so that there is a problem that water separation occurs over time in the ink pan and the pot, while emulsification occurs when the content exceeds the above range. There is a problem in that good printability cannot be obtained because of being too stable.
[0019]
As the binder resin component used to obtain the emulsion ink composition for offset printing of the present invention, rosin-modified phenol resin, various alkyd resins, petroleum resins, rosin ester resins, polyester resins, gilsonite, or modified products thereof are used. can do. These resin components may be gelled using a gelling agent. These resin components can be used alone or in combination of two or more.
[0020]
As the colorant for obtaining the emulsion ink composition for offset printing of the present invention, colorless or colored, inorganic or organic pigments generally used for offset printing inks can be used, specifically, titanium dioxide, sulfuric acid. Inorganic pigments such as barium, calcium carbonate, and magnetic iron oxide, azo pigments, lake pigments, phthalocyanine pigments, isoindoline pigments, anthraquinone pigments, organic pigments such as quinacridone pigments, and carbon black can be used. These colorants can be used alone or in combination of two or more.
[0021]
Examples of the vegetable oil for obtaining the emulsion ink composition for offset printing of the present invention include soybean oil, cottonseed oil, linseed oil, safflower oil, tung oil, tall oil, dehydrated castor oil, canola oil and the like. As the mineral oil for obtaining the emulsion ink composition for offset printing of the present invention, those used as offset printing ink solvents can be used without particular limitation. Specific examples include petroleum solvents such as n-paraffin solvents, isoparaffin solvents, naphthene solvents, aromatic solvents, α-olefin solvents, spindle oil, machine oil, and cylinder oil. Specific examples of other solvents that can be used in combination include light oil, turpentine oil, mineral spirit, alcohols, ketones, esters, and the like. These vegetable oils and mineral oils can be used alone or in combination of two or more.
[0022]
Furthermore, in order to obtain the emulsion ink composition for offset printing of the present invention, a pigment dispersant, a drying retarder, an antioxidant, a surface conditioning aid, an anti-backing agent and the like can be appropriately used.
[0023]
The ratio of the colorant, binder resin, vegetable oil and / or mineral oil in the emulsion ink composition for offset printing of the present invention is 8 to 30% by weight of the colorant and 8 to 45% by weight of the binder resin in the total ink composition. The range of 0 to 60% by weight of vegetable oil and 0 to 60% by weight of mineral oil (the total amount of vegetable oil and / or mineral oil is preferably in the range of 25 to 60% by weight) is appropriate.
[0024]
As water for obtaining the emulsion ink composition for offset printing of the present invention, ion-exchanged water, distilled water, natural water, tap water and the like can be used.
[0025]
The water is contained in an emulsion ink composition for offset printing in an amount of 1 to 15% by weight. If the water content is less than the above range, if the ink supply method is a basin method, there will be a problem of dripping from the jar. On the other hand, if it exceeds the above range, if the ink supply method is a basin method, There arises a problem that smooth ink supply cannot be performed.
[0026]
In order to produce the emulsion ink composition for offset printing of the present invention, a conventionally known method can be used. Below, the general manufacturing method used in order to obtain the emulsion ink composition for offset printing of this invention is demonstrated.
[0027]
A base for offset printing ink is obtained by dispersing a resin varnish, a colorant, a vegetable oil, a mineral oil and, if necessary, a pigment dispersant with a bead mill, a three-roll mill or the like.
[0028]
To the base for offset printing ink, a higher alcohol and a nonionic surfactant specified in the present invention, a resin varnish that can be used as necessary, and other additives as necessary are added, such as vegetable oil and mineral oil. An offset printing ink composition is obtained by adjusting to a predetermined viscosity.
[0029]
Water is added to the ink composition for offset printing and stirred to obtain an emulsion ink composition for offset printing.
[0030]
The emulsion ink composition for offset printing of the present invention can also be used in a plunger pump type and digital pump type offset printing machine having different ink supply methods.
[0031]
【Example】
Hereinafter, the emulsion ink composition for offset printing of the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to these without departing from the spirit and scope of application. In the following description, “parts” indicates parts by weight.
[0032]
[Manufacture of varnish for ink for offset printing]
(Production of rosin-modified phenolic resin gel varnish)
Four-necked flask equipped with a condenser, thermometer, and stirrer is rosin-modified phenolic resin (manufactured by Hitachi Chemical Co., Ltd., acid value 20, softening point 162 ° C.) 38.5 parts, soybean oil 30 parts, No. 6 solvent 30 parts (manufactured by Nippon Petrochemical Co., Ltd.), charged to 230 ° C., stirred at the same temperature for 30 minutes, allowed to cool, and 1.5 parts ethylacetoacetate aluminum diisopropoxide as a gelling agent ( Kawaken Fine Chemical Co., Ltd. ALCH) was added and stirred at 175 ° C. for 30 minutes to obtain a rosin-modified phenolic resin gel varnish.
[0033]
(Manufacture of Gilsonite Varnish)
A four-necked flask equipped with a condenser, a thermometer, and a stirrer was charged with 20 parts of Gilsonite Select (manufactured by American Gilsonite Co., Ltd.) and 80 parts of No. 6 Solvent. And stirred for 4 hours to obtain a gilsonite varnish.
[0034]
(Manufacture of petroleum resin varnish)
A four-necked flask equipped with a condenser, a thermometer, and a stirrer was charged with 55 parts of maleated petroleum resin (manufactured by Nippon Oil Co., Ltd.) and 45 parts of No. 6 solvent, heated to 140 ° C., and then heated to 30 at the same temperature. A petroleum resin varnish was obtained by stirring for a minute.
[0035]
[Production of emulsion ink composition for offset printing]
Examples 1-9, Comparative Examples 1-7
40 parts of rosin-modified phenolic resin varnish, 12 parts of gilsonite varnish, 12 parts of petroleum resin varnish, 20 parts of carbon black # 32 (Mitsubishi Chemical Co., Ltd.), 1 part of anti-drying agent and kneaded in a bead mill. A black ink base was obtained. Next, with respect to the black ink base, a higher alcohol, a nonionic surfactant, a petroleum resin varnish, and No. 6 solvent are added and diluted with the composition shown in Table 1, and the viscosity is offset from 6.0 to 6.5 Pa · s. A printing ink composition was obtained, and then each offset printing ink composition obtained above and water were stirred and mixed so as to have the composition shown in Table 1, and Examples 1 to 9 and Comparative Examples 1 to 7 An emulsion ink composition for offset printing was obtained.
[0036]
[Performance evaluation test]
The offset printing emulsion ink compositions obtained in Printing Test Examples 1 to 9 and Comparative Examples 1 to 7 were offset printed under the following printing conditions, and ink dripping from the vase type vase, ink ejection from the vase (Judgment is based on whether or not the required amount of ink has been discharged from the fountain for a certain period of time.) Investigated about dirt. The results are shown in Table 2.
[0037]
(Evaluation)
<Drip of ink from the pot>
3: The ink is not dripping from the jar 2: The ink is slightly dripping from the jar 1: The ink is dripping a lot from the jar [0038]
<Ink ejection from the pot>
3: Good ink discharge from ink fountain 2: Slightly good ink discharge from ink fountain 1: Bad ink discharge from ink fountain
<Ink fluidity on ink pan and blade>
3: With good ink fluidity 2: With slightly poor ink fluidity 1: With poor ink fluidity
<Status of printed paper>
3: When the printing paper surface is not dirty 2: When the printing paper surface is slightly dirty 1: When the printing paper surface is conspicuous
<Printing conditions>
Vase type printing machine: Vase type newspaper-off-wheel printing press Plate Material: PS plate dampening water: Alkaline dampening water Paper: Newspaper printing speed: 24,000 copies / hour to 140,000 copies / hour Keyless printing Machine: Keyless newspaper-off-wheel printing press Plate Material: PS plate dampening water: Alkaline dampening water Paper: Newspaper printing speed: 24,000 copies / hour to 140,000 copies / hour [0042]
[Table 1]

[0043]
[Table 2]

[0044]
【The invention's effect】
The emulsion ink composition for offset printing containing a specific higher alcohol and a nonionic surfactant of the present invention and a specific amount of water is fundamental in terms of halftone dot reproducibility, fleshing property and suitability for stains. It has printability and prevents dripping from the vase specific to the vase, discharge from the vat, fluidity in the ink pan specific to the keyless method, and fluidity on the blade. Sharing on the machine became possible.

Claims (1)

An emulsion ink composition for offset printing comprising a colorant, a binder resin, a vegetable oil and / or mineral oil, and water as main components, and represented by the following general formula (1) in the entire ink composition 0.1 to 5.0% by weight of a higher alcohol and 0.1 to 3.0% by weight of a nonionic surfactant represented by the general formula (2), and water in the total ink composition An emulsion ink composition for offset printing, comprising 1 to 15% by weight.
R ¹ —OH (1)
_{^{R 2 -O- (CH 2 -CH 2}} -O) n-H (2)
(Wherein R ¹ is a saturated hydrocarbon group having 8 to 24 carbon atoms or may contain an unsaturated bond, and R ² is a saturated hydrocarbon group having 4 to 24 carbon atoms, or A hydrocarbon group which may contain an unsaturated bond and / or an aromatic ring, n represents an integer in the range of 1 to 16, and k represents the carbon number of R ² , k and n are 1.5n ≦ k ≦ 6n relationship is satisfied)