JPS6128433A - Pigment dispersant - Google Patents

Abstract

PURPOSE:To obtain a stable dispersion, by preparing the same by using an ester compound obtained by reacting monohydric alcohol represented by formula ROH with a piperylene/maleic anhydride adduct represented by a specific general formula. CONSTITUTION:A pigment dispersant is prepared from a carboxyl group-containing ester compound obtained by reacting monohydric alcohol represented by formula R-OH (wherein R is 4-20C alkyl, alkoxyalkyl, aralkyl, aryloxyalkyl or cycloalkyl) with 5-(2,5-dioxotetrahydro-3-furyl)-methyl-3-cyclohexene-1,2-dicarboxylic anhydride represented by formula. The relative ratio of this dispersant in a dispersion is 0.1-100%, pref., 0.1-10% on the basis of a pigment component and the content of the pigment in the dispersion is 5-80%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides particularly improved fluidity and monodispersion stability for dispersions of inorganic or organic pigments in organic liquids. It relates to a compound that has the property of imparting properties, and its scope of application extends to the general field of various printing inks and paints such as lithographic inks, gravure inks, 7-lexo inks, and metal inks.

[Problems that the invention helps solve]

In general, practically useful pigments that exhibit high coloring power and vivid color tone in various coating compositions such as printing inks and paints are composed of fine particles.

However, when fine pigment particles are dispersed in non-aqueous vehicles such as offset inks, gravure inks, and paints, it is difficult to obtain stable dispersions, which may affect the manufacturing process and the quality of the resulting products. In many cases, they cause various problems without having a significant impact.

That is, dispersions containing pigments consisting of fine particles often have a high viscosity, which makes handling difficult when removing the product from the dispersion machine or during transport, and in some cases significantly increasing the viscosity during storage. It is known that undesirable phenomena such as increased viscosity and difficulty in use, fussiness, floating, loss of gloss, and discoloration over time occur.

Non-aqueous printing inks or coatings are pigment dispersions in organic liquids containing vehicle polymers and other auxiliaries.

A fundamental part of their rheological properties depends on the nature of the pigment.

In other words, it may be extremely viscous and show almost no fluidity, or it may have poor wettability with organic liquids and not disperse at all.
In systems exhibiting significant chicken-like properties, the pigment may be present substantially completely or in a highly agglomerated state;
This type of colorant not only has poor fluidity, but also tends to have a lower color density in the paint film than colorants with good dispersibility, and the gloss tends to be significantly lower because the painted surface lacks smoothness. Ru.

[Conventional technology]

Many attempts have been made to prevent the above-mentioned agglomeration of pigments, and these attempts have been found to be effective to some extent.

For example, British Patent No. 949.759 describes a cyanine group of the following formula, R8 represents hydrogen or an aliphatic group,
R3 represents an aliphatic group, or R3 and R1 together with the nitrogen atom to which they are bonded represent a heterocyclic group, and n is 1
~4 is shown. The use of agglomeration-inhibiting phthalocyanine derivatives represented by ) has been reported, but of course this can only be applied when the pigments treated therewith have similar color tones.

Furthermore, JP-A-55-112273 discloses that polyurea derivatives of the type are effective for dispersing pigments, and British Patent No. 542,746 and U.S. Patent No. 3. No. 778゜287 reports a dispersant related to a polyester or a salt thereof obtained by dehydrating a hydroxycarboxylic acid such as 12-hydroxystearic acid. British Patent No. 1.375.660 describes that esters or amides containing amino groups or ammonium salts are effective for dispersing pigments.

[Failure to solve the problem]

The present inventors have now discovered that fine powdery solids are present in organic liquids.
In particular, when dispersing organic or inorganic pigments, we have discovered a new group of compounds that are extremely effective in preventing agglomeration of pigments in the dispersion and forming a stable dispersion.

The pigment dispersant of the present invention has 5-(2,5-
Carboxyl obtained by reacting monohydric alcohol represented by RoH with dioxo-3-furyl)-6-methyl-3-cyclohexene-1,2 dicarboxylic anhydride (hereinafter referred to as piperylene maleic anhydride adduct). It consists of a group-containing ester compound.

OCR, 0 Piperylene maleic anhydride adduct is
As stated in the 1955 BAm book, transformer,
or 3-methyl-4-cyclohexene-1,2 obtained by the reaction of cis-1,3-pentadiene and maleic anhydride.
- Manufactured by reacting maleic anhydride with dicarboxylic anhydride, this product is not only used as a raw material for heat-resistant polyamide resin, but also
As described in No. 214, it is a compound that is useful as a curing agent for epoxy resins, but it has been previously known that carboxy-containing ester compounds obtained by reacting with -hydric alcohols are useful as pigment dispersants. It wasn't.

The monohydric alcohol used in the present invention includes aliphatic-
Alcohols such as n-butanol, lso-butanol, set, butanol, aluminum alcohol, ig
o-amyl alcohol, lauryl alcohol, n- and iso-stearyl alcohol, etc.), alicyclic alcohols such as cyclohexanol, cyclopentanol, Schifftetraoctatool, cyclododecanol, etc., phenyl substituted alcohols Examples include benzyl alcohol, β-phenylethyl alcohol, etc. Furthermore, alkoxy-substituted alcohols such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, etc., and phenoxy-substituted alcohols include, for example, 1-
(4-4ertbutylphenoxy)-2-butanol can be mentioned, and these alcohols may be used alone or as a mixture in any molar ratio.

The reaction ratio of these acid components and alcohol components is preferably 2 to 3 moles of the sea alcohol alone or as a mixture per 1 mole of piperylene maleic anhydride adduct. In short, it is sufficient that the carboxyl group is contained in a proportion that allows the desired effect of the present invention to be obtained. When the alcohol component decreases by 2 moles and the carboxylic acid anhydride increases (by 9.6 moles), esterification progresses excessively and the carboxyl group content decreases, and in both cases, the desired performance decreases. Therefore, it is difficult to say that it is suitable.

The esterification reaction of piperylene maleic anhydride adduct and -hydric alcohol can be carried out using known catalysts such as phosphoric acid, P-
) Ruenesulfonic acid, methanesulfonic acid, tetra-
120 to 200°C in the presence of n-butyl titanate, etc.
, preferably by removing the produced water from the system while heating to 140-185° C., preferably by passing nitrogen gas over the reaction mixture or by forming an azeotrope with water. aromatic hydrocarbons such as toluene,
It is advantageous to azeotropically remove the water produced in the presence of xylene.
It goes without saying that when less than a molar amount of monohydric alcohol is added, esterification by the L1 addition reaction only occurs and water cannot be distilled out).

The degree of progress of the esterification reaction can be determined by measuring the acid value or measuring the residual degree of raw material alcohol using high performance liquid chromatography.

Examples of the organic liquid used in the dispersant of the present invention include aromatic hydrocarbons such as toluene and xylene, petroleum hydrocarbons such as mineral spirit and mineral turpentine, and halogenated hydrocarbons such as chloroform and chlorobenzene.
7) Y, Ketones such as methyl ethyl ketone, methyl imbutyl ketone, and isophorone, and esters such as ethyl acetate, butyl acetate, amyl acetate, and cellosolve acetate, but of course two or more of these types may be used. It may be a mixed solvent of 1, or a mixed solvent with known alkyd resins, epoxy ester resins, melamine resins, acrylic resins, polyamide resins, polyurethane resins, vinyl resins, nitrocellulose resins, etc.

Fine powder solids, usually less than 20 microns in diameter, to be dispersed in organic liquids include titanium dioxide, red and yellow iron oxides, barium sulfate, Merck, clay, lead chromate, strontium tetramate, carbon. Examples include inorganic pigments such as black, organic pigments such as azo pigments, azo lake pigments, 7-thalocyanine pigments, isoindolinone pigments, and quinacridone pigments.

The relative proportion of the dispersant according to the invention in the dispersion liquid is 0.1 to 100%, preferably 0.1% to the pigment content.
The pigment content in the dispersion is preferably 5 to 80%, preferably 10 to 70%.

〔Effect of the invention〕

The pigment dispersions according to the invention exhibit particularly good color strength, film gloss and fluidity, storage stability when used in surface coating applications, for example in the production of non-aqueous paints, lacquers and printing inks; Toshiwake epoxy ester/melamine resin vehicle not only improves the fluidity of shochu-type metal inks, but also reduces the adhesion of the paint film to metal, which is often seen with conventional dispersant formulations. It has the advantage that it is not recognized.

Furthermore, the application advantages include that compared to ordinary printing inks, it has a much higher pigment concentration and can be milled in a shorter time, reducing labor, electricity, and consumable costs required for milling. In addition, good fluidity is maintained even when the pigment concentration in the dispersion is increased, making it possible to reduce storage and transportation costs.

(1) The advantages of the pigment dispersant according to the present invention are: (1) efficiency of pigment dispersion time, stabilization of the pigment dispersion state in the finished printing ink or paint, and flocculation. You can improve the prevention, leveling improvement, color separation prevention, etc.

〔Example〕

The present invention will be explained in more detail with reference to Examples below.

Of course, the gist and scope of the present invention are not limited to these examples.

Note that parts in the examples mean parts by weight.

Example 1 Polyester A Epicron ■B-4400 (Dainippon Ink Chemical Co., Ltd. = 5-
2.5-dioxotetrahydrogen-4-5-7lyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride) 264.219.2-4thylhexylalco-h
390.71 'F Tetra-n in a mixture of 60 g of silene
-Butyl titanate α5It″ added to 165% in nitrogen stream
The mixture was heated under reflux at -170°C for 6 hours, and 17.9 JiF of water was separated using a Dean-Stark trap.

Reaction solution t-150°C/20. The low boilers were removed by keeping at HIi for 2 hours to give 634.5.9, a pale reddish-brown, clear, viscous oil.

Acid value of this thing #l; i: 85.3th f! KOH/77
Met. , Example 2 Polyester B Epicron B-4400132, 130.2 g of 1,9,2-ethylhexyl alcohol, 3oI of xylene
Add iK Tetra n-butyl titanate α19, 14
The mixture was heated and stirred at 0'C for 4 hours. Reaction product f150℃
It was kept under reduced pressure of 720 wHg for 3 hours to remove low boiling point substances.
A pale reddish-brown, transparent and extremely viscous oily ester compound of 260.7.9 was obtained.

The oxidation of this product was 205.419 KOH/7.

Example 3 A mixture of polyester C Epiclon B-4400132, 1jl, n-octyl alcohol 195.3L The water produced was separated in a Dean-Stark trap. Water from the esterification reaction 911 was collected and removed.

The reaction mixture was heated to 160”C under a vacuum of 20wHJii.
As a result of keeping it for a long time and removing low boiling point substances, the acid value was 795 KOH.
/I! Pale reddish brown, transparent, viscous polyester compound 51
Obtained on 5.511.

Example 4 Polyester D Epicron B-440066, 1,7 Ein Oxocol ■ 180 (Nissan Chemical: Instearyl Alcohol Molecular Weight 270.5) 202.9N, Xylene 30.9, Tetra n Butyl Titanium) 0.2 # The mixture was heated to reflux at 170-175°C in a nitrogen stream to separate and remove water, resulting in 5g of water in a Dean-Stark trap.
of water separated.

The reaction product was kept at 160° C. under a reduced pressure of 20 mHI for 6 hours to remove low-boiling substances to obtain polyester 265.5 II, which was a light reddish-brown, transparent, and extremely viscous oil. Acid value 48.8
m9KOH/I.

Example 5 Polyester E Epiclon B-4400:132.1.9. Cyclohexanol 150.2. V, xylene 40g, Tet:)n
Butyl titanate 0.4. A mixture of P in a nitrogen stream at 1
The mixture was heated under stirring and refluxed at 70 to 175° C. for 10 hours, and 8.8 I of water was separated in a Dean-Stark trap.

The reaction product was kept at 160°C under a vacuum of 30wH# for 3 hours to remove low-boiling substances, and the product became pale reddish-brown, transparent, and extremely viscous.
Polyester compound 268 that solidifies like starch syrup at room temperature
．． 8g was obtained.

The acid value of this product was 102.1 qKOH/Ii.

Example 6 Polyester F EpicoyB-440066,0! A mixture of 0.3Ji1, lauryl alcohol 139.8N, xylene 409N, and tetra-n-butyl titanium was heated to 18
4.5.9 Heat and stir at 0 to 185°C for 4 hours and reflux.
water was distilled off.

The reaction product anastomoses and is kept at 160°C for 3 hours under reduced pressure of 20 mHI to produce a pale reddish brown, transparent, and viscous polyester compound 20.
11 g was obtained. The acid value of this thing is 65.7ve￥:(
%/I.

Example 7 Polyester G Epiclon B-440066,019, lauryl alcohol q5.21. A mixture of 0.2 g of xylene 3011 tetra-2n-butyl titanate was heated and stirred at 170° C. for 2 hours in a nitrogen stream.

The reaction product was maintained at 160° C. for 3 hours under a reduced pressure of 20 wHJ to remove low boiling point substances. Pale reddish-brown transparent, viscous polyester compound 15B, 1 whole culm. The acid value of this thing is 17
It was 2.5 wings gK OH/11.

Example 8 Polyester H Epicron B-□4400 66.0#, 2-ethylhexylurethane 8 (L61% stearyl alcohol-A/
36.0 f' A mixture of 30 g of Φ silene and 0.21 i of tetra n-butyl titanate was heated under reflux at 170°C in a nitrogen stream for 4 hours to distill off moisture.
4.5 g of water separated in the Dean and Stark traps.

When the reaction product was kept under a reduced pressure of 30 mm Hg for 6 hours to remove low boiling point substances, pale reddish brown transparent viscous oily polyesters 17B and 8JF were obtained.

The acid value of this product was 76.7 qKom/I.

Example 9 l-(2/-sulfo-4'-methylphenylazo)-2
- A mixture of 6 parts of calcium lake of naphthol-3-carboxylic acid, 5.5 parts of polyester AtS, and 5.5 parts of xylene was shaken with 10 parts of 6-day diameter steel balls for 3 hours in a Red Devil paint shaker to deflocculate the mixture. I let it happen.

The dispersion was suitable for use in gravure printing inks and showed no tendency to flocculate or settle for at least one week.

Example 10 A mixture of rutile-type titanium white 5R-IA (5 parts of Sakai Kagaku Co., Ltd., 81 parts of polyester, and 4 parts of isophorone) was prepared in a diameter of 3 m.
The mixture was shaken for 6 hours with 10 parts of steel balls in a Red Devil paint shaker to peptize and disperse.

The dispersion exhibited good fluidity and was suitable for use in Gutsubya printing inks, without agglomeration or sedimentation for at least one week.

Example 11 A mixture of 6 parts of Thioxide R-CR (rutile titanium white coated type manufactured by BTP), 1 part of polyester 0, and 3 parts of mineral spirit was mixed with 10 parts of a steel ball having a diameter of 3 m in a paint shaker manufactured by Red Devil for 6 hours. The mixture was thoroughly deflocculated and dispersed by shaking.

The dispersion was suitable for the production of gravure printing inks and showed no tendency to flocculate or settle for at least one week.

Example 12 Barium lake of 1-(2'-sulfo-41-methyl-5'-chlorophenylazo)-2-naphthol-3-carboxylic acid (C,1, Pigment Red 48 1
), 0.1 part of polyester, and 5.5 parts of xylene were shaken together with 10 parts of a steel ball with a diameter of 3 in a paint shaker for 4 hours to sufficiently deflocculate and disperse.

The dispersion liquid was suitable for producing gravure printing ink and had good starvation dispersion stability.

Example 16 10 parts of steel balls with a diameter of 3w11 were added to 5 parts of rutile-type titanium white 5R-IA (manufactured by Sakai Chemical Co., Ltd.), 10.5 parts of polyester, and 4.5 parts of xylene, and the mixture was thoroughly dissolved by shaking with a paint shaker for 4 hours. Glue, dispersed.

The dispersion exhibits good fluidity and lasts for at least - weeks.
It showed no tendency to coagulate and settle, and was suitable for producing gravure printing inks.

Example 14 Lake Red C (C, 1, P1gm@nt Red 5
5) 4 parts, 11 parts of polyester, toluene/ME
10 parts of steel balls with a diameter of 3+ m were added to 5 parts of K(I/1), and the mixture was sufficiently deflocculated and dispersed by shaking in a paint shaker for 4 hours. The dispersion had good fluidity and showed no tendency to coagulate and settle for at least 1 week, and was suitable for producing a gravure printing ink.

Claims (1)

[Scope of Claims] R-OH (R is , alkyl having 4 to 20 carbon atoms, alkoxyalkyl, aralkyl,
A pigment dispersant comprising a carboxyl group-containing ester compound obtained by reacting a monohydric alcohol represented by aryloxyalkyl or cycloalkyl groups. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) 2. Claim No. 1, which is obtained by reacting 2 to 3 moles of monohydric alcohol with 1 mole of acid anhydride (I). Pigment dispersant according to item 1.