JPS60248711A - Nonaqueous resin dispersion - Google Patents

Abstract

PURPOSE:The titled dispersion useful as a liquid developing agent for electrostatic photography, printing ink, coating compound, etc., controlling easily viscosity, having no variability of product, obtained by polymerizing specific two (meth) acrylate monomers in an aliphatic hydrocarbon solvent. CONSTITUTION:At least (A) a monomer (e.g., lauryl methacrylate, etc.) shown by the formula I [X is H, or CH3; R is -COOCmH2m+1, or -OCOCmH2m+1 (m is 6-20)] and (B) a monomer (e.g., compound shown by the formula III, etc.) shown by the formula II (R1-R4 are H, COOH, OH, or 1-4C alkyl; n is 1-20) in a weight ratio of the monomer A/B of preferably = 50-99.5/0.5-50 are polymerized in an aliphatic hydrocarbon solvent (e.g., kerosine, etc.) in the presence of a polymerization initiator (e.g., benzoyl peroxide, etc.), to give the aimed dispersion. Preferably addition of silica powder during preparation process improves further dispersion stability.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD This invention relates to non-aqueous resin dispersions useful in applications such as electrostatographic liquid developers, printing inks, adhesives, and coatings.

Conventional technology Non-aqueous resin dispersions can be used for various purposes such as electrostatographic liquid developers and printing inks. As is well known, in a liquid developer, a toner mainly composed of a colorant and a resin is dispersed in a carrier liquid such as an aliphatic hydrocarbon solvent.A wet development transfer method using such a liquid developer It is known that it is preferable to use a cross-linked resin as a toner resin in order to increase the transfer efficiency.Also, this cross-linked resin is polymerized with a heptamer having two or more vinyl groups in one molecule. It has the advantage that it can be produced in one step. Conventionally, such crosslinked Ishiba has been produced by solution polymerization of vinyl group-containing monomers in the presence of a polymerization initiator according to a conventional method, or Because it is difficult to control the crosslinked resin, it is difficult to stably produce a crosslinked product in solution, and there is also a large degree of unevenness in the product between manufacturing lofts. However, when pigments such as carbon black were dispersed, stability and redispersibility were insufficient.

Objective The first objective of the present invention is to provide a non-aqueous resin dispersion whose viscosity can be easily controlled and which causes less unevenness of the product between manufacturing lofts.

The second object of the present invention is to provide a non-aqueous resin dispersion having a large number of polar groups in the pattern 8H molecule, which has excellent dispersion stability and redispersibility when pigments are dispersed therein.

Composition The non-aqueous resin dispersion of the present invention is prepared in an aliphatic hydrocarbon solvent in the presence of a polymerization initiator with at least the general formula % [where X is -H or -CH, and R is -C000fflH]
! ! Tl+1 or -0000mH, m+1 (m is 6~
(an integer of 20)] and a monomer A represented by the general formula ■ (where X is as described above, and R1, R3, R,, R4 are))
rogene, -H1-C0OH, -OH or a C8 to C4 alkyl group, n is an integer of 1 to 20].

The inventors of the present invention have conducted various studies on what kind of properties the resin (polymer) should have in order to achieve all of the above objects, and have reached the following conclusion. That is, the properties of this polymer are: 1) A solvate component is present in the polymer, and this polymer has a uniform crosslinking structure; 2) A crosslinking monomer component that does not undergo a rapid crosslinking reaction is important. , 3) It contains a 7-mer component that causes copolymerization and crosslinking reactions to occur separately, 4) It has an affinity for pigments, and 5) It does not dissolve in non-aqueous solvents and (
It is simply that it can be dispersed in a non-aqueous solvent. Therefore, the present inventors investigated various polymers from these viewpoints, and as a result, they found that they can be solvated both before and after polymerization, and that they can be polymerized with a 7-mer A such as an unsaturated compound of the general formula (1). Subsequently, it was discovered that a copolymer obtained by copolymerizing and crosslinking monomer B of the general formula n with a monomer B that can serve as a crosslinking component is optimal.The present invention is based on such knowledge. It is based on

To prepare the copolymer resin dispersion of the present invention, monomer A and monomer B as described above are generally mixed in a nonaqueous solvent mainly composed of petroleum-based aliphatic hydrocarbons with penzoyl monooxide, azobisisobutylene oxide, The polymerization may be carried out by heating in one or two stages in the presence of a polymerization initiator such as nitrile. here"
``One step'' means heating monomer A and monomer B to a relatively high temperature of about 60 to 150°C in the presence of a polymerization initiator such as benzoyl peroxide that causes polymerization at a relatively high temperature. Sumire means to cause a polymerization reaction.
"Two-step" means that monomer A, monomer B and 8 are first heated to a relatively low temperature of about 60 to 90°C in the presence of a polymerization initiator such as azobisisobutyronitrile that causes polymerization at a relatively low temperature. After the polymerization reaction was carried out, the above-mentioned high temperature polymerization initiator was added to the reaction solution, and in the presence of this rich temperature initiator, 9
Either perform the polymerization reaction again by heating to a relatively high temperature of about 0 to 150°C, or first polymerize only Nanatsuma-B under similar low-temperature conditions, and then add monomer A and high-temperature polymerization to the reaction solution. This means that the polymerization reaction is carried out again under the same high temperature conditions in the presence of this room temperature polymerization initiator. In any case, in both the one-stage polymerization reaction and the two-stage polymerization reaction, it is thought that a copolymerization reaction and an equipment reaction are involved.

Note that wvv, tt memomer A/monomer B ratio is 50~
Approximately 99.5 to 10.5 to so (by weight), and the polymerization initiator is the monomer (weight) used in each polymerization step.
In the case of one stage, 0.1 to s% (weight) of the total amount
The degree is appropriate.

Further, in the present invention, other polymerizable monomers, silica fine particles, wax or polyolefin having a softening point of about 60 to 130°C can be added to the copolymer manufacturing process. When fine silica particles are used, it is thought that the copolymer is obtained with fine silica particles incorporated into its crosslinked structure.

In this case, it is thought that the silica itself will not undergo physical changes such as dissolution during the reaction. By doing so and preventing gelation of the copolymer, dispersion stability can be significantly improved. On the other hand, when wax or polyolefin is used, these are either dissolved in the reaction system by heating during the polymerization reaction, or precipitated into particles by cooling after the reaction, resulting in the copolymer being adsorbed on these fine particles. It is considered that the Here, wax or polyethylene has a specific gravity similar to that of the dispersion medium, prevents gelation of the copolymer, and has a molecular structure similar to that of the dispersion medium, so it not only helps improve dispersion stability but also has a low softening point. Therefore, it also helps improve adhesion. The amount of silica, wax or polyolefin added is approximately 5 to 50 parts by weight per 100 parts by weight of the copolymer.

Next, the materials used in the present invention will be explained as specific examples of the monomer A of the general formula 0. hexyl acrylate, dodecyl methacrylate, dodecyl acrylate,
Examples include cyclohexyl acrylate, cyclohexyl methacrylate, hexyl methacrylate, hexyl acrylate, octyl methacrylate, octyl acrylate, cetyl methacrylate, cetyl acrylate, vinyl laurate, and vinyl stearate.

Specific examples of the monomer B of the general formula (2) include the following.

Structural formula Compound OOH Structural formula Compound 4 Polymerization initiators for low-temperature polymerization include azobisisobutyronitrile, benzoyl peroxide dimethylaniline,
Diethyl zinc, water storage peroxide, etc., and those for high temperature polymerization include benzoyl peroxide, lauryl peroxide, t-butyl oxide, di-t-butyl peroxide, cumene hydro/zo oxide, dicumyl. There are peroxides, etc.

Aliphatic hydrocarbons used as reaction solvents include kerosene, ligroin, cyclohexane, n-hexane, n
-Pentane, n-hebutane, n-octane, inoctane, indodecane, isononane (the above commercial products -(
are Exxon's Isopar E, G, L, K:
Naphtha rot 6 and Shell Sol made by Shell Oil Co., Ltd.),
Examples include carbon tetrachloride, perchloroethylene, and fluoroethylene. These aliphatic hydrocarbons have high insulating properties (electrical resistance of 1010 Ω·α or more) and can be added with a small amount of an aromatic solvent such as benzene or toluene to achieve a low dielectric strength.

In the present invention, other polymerizable monomers,
Wax-like substances, etc. can be used; other synthetic compounds such as styrene, vinyltoluene, nitrostyrene, vinyl acetate, vinylpyrrolidone, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, diethylamino Examples include ethyl acrylate.

Specific examples of commercially available waxes or polyolefins with a softening point of 60 to 130°C are as follows.

Example of polyethylene Union car Aite @) DYNI 102DYNF 1
02 DYNH102 DYNJ 102 DYNK 102 Monsanto Rest) ORLIZON 805 116tt
705 116 # 50 126 F i Ritsu System@) MARLEX 1005 9
2 Du Pont (USA) ALATHON-3103/
/ 10 96 //12 84 // 14 80 〃16 95 1/ 20 86 /' 22 84 tt 25 96 Allied Chemica AQIF) AC-4 Lietelen 170
2 98 Manufacturer Product Name Softening Point (f for olfactory chemical) AC-yjr Liethylene 6&
6A 102# 615 105 Sanyo Chemical Sunwax 131-P 108I
151-P 107 tt 161-P 111 tt 165-P 107 tt 171-P 195 〃 E-20095 Genuine Kagaku Nozo Rough In Wax 6 To 48 Small
Hayashi Kako Exposed Beeswax 65 Setanol 80 Nagai Kako Exposed Beeswax 65 Iron Chemicals Frozen 110 Examples of the present invention are shown below.

Example 1 3t equipped with stirrer, thermometer, cooling pipe, and dripping port
50 of kerosene in a flask, 85
C. While stirring, monomer B502 (lauryl acrylate) 1001F, /761 and 5 tons of azobisisobutyronitrile were added dropwise to the mixture via a dropping funnel over 2 hours. Thereafter, the polymerization reaction was carried out at this temperature for 4 hours with stirring, then di-t-butyl peroxide 32 was added, and the molding reaction was further carried out at 111)'C for 6 hours, resulting in a polymerization rate of 96% and a viscosity of 300 cp. A resin dispersion was prepared.

Example 2 400f of n-hexane was placed in the flask used in Example 1, heated to 60°C, and while stirring, lauryl methacrylate 95F, monomer B25f of 44, and azobisisobutyronitrile 2flj were added using a dropping funnel for 1 hour. The mixture was added dropwise, and then the polymerization reaction was carried out at this temperature for 6 hours. Next, add 4f of benzoyl peroxide and
By further carrying out a polymerization reaction under stirring at 4 o'clock i=J,
A resin dispersion with a polymerization rate of 99.0 and a viscosity of 260 cp was obtained.

Example 3 Isopar G 4001F was added to the flask used in Example 1.
The mixture was heated to 90° C., and stearyl meccrylate 200f, A6 monomer BIOP, and benzoyl peroxide 32 were added dropwise over 4 hours using a dropping funnel while stirring. Next, styrene 309 and benzoyl peroxide 3f were added and a polymerization reaction was carried out at the above temperature for 4 hours with stirring to obtain a non-aqueous resin dispersion with a polymerization rate of 93.8% and a viscosity of 390 cp.

Example 4 2 oor of n-hebutane and 50 r of polyethylene (AC polyethylene 1106 manufactured by Allied Chemical Co., Ltd.) were placed in the flask used in Example 1, and heated to 90°C to dissolve the polyethylene.

In this, monomer B200f of 應9 and azobisiso,
Butyronitrile (1t)ff was added dropwise over a period of 2 hours using a dropping funnel, and the reaction was carried out at the same temperature for 6 hours with stirring.Next, 100f of cetyl methacrylate and 5f of t-butyl chloride oxide were added, and the mixture was further heated to 130°C. By carrying out a polymerization reaction under stirring for 6 hours, a polyethylene-containing resin dispersion having a polymerization rate of 964 cm and a viscosity K of 530 cp was obtained.

Example 5 13F of ACJ IJ ethylene 610 was added to the resin dispersion obtained in Example 2 (dissolved by heating at 90° C. for 2 hours, then left to cool to produce a polyethylene-containing resin dispersion having a viscosity of 120 cp).

Example 6 40 l of Sunwax 131-P was added to the polyethylene-containing 1a4 k1 dispersion obtained in Example 4, and the mixture was heated at 90°C for 2
After heating and dissolving for a period of time, the mixture was allowed to cool to produce a wax and polyethylene-containing resin dispersion having a viscosity of 330 ep.

Effects As described above, according to the present invention, by using the 281 specific seven-mers in combination, the viscosity can be easily controlled, and there is little variation in the product between manufacturing lofts.
A non-aqueous resin dispersion having excellent dispersion stability and redispersibility when a pigment is dispersed can be obtained.

Claims (1)

[Claims] L In an aliphatic hydrocarbon solvent, in the presence of a polymerization initiator, the general formula ■ cH,=c-x [where X is -H or -CH, R is -OOOCmHzm +, Or -〇〇〇〇mH2m+,
(m is an integer from 6 to 20)] Seven-dimensional A and general formula B [However, as mentioned above, Monomer B represented by a C4 alkyl group, n is an integer of 1 to 20)
A non-aqueous resin dispersion obtained by polymerizing.