JPS60218662A - Electrostatic photographic liquid developer - Google Patents

Abstract

PURPOSE:To impart continuous gradation and affinity to printing ink grease by dissolving a specified copolymer in a solvent. CONSTITUTION:A toner essentially consisting of a resin is dispersed into a nonaq. solvent having >=10<9>OMEGA.cm resistivity, and a dielectric constant of <=3.5, and it is mixed with a monomer capable of polymerizing to form a soluble polymer, and further with a monomer represented by formula I or II in which R1, R2, R3, R4 may be same or different, and each is H, alkyl, carboxy, or -COOL, L being a hydrocarbon group; X1 and X2 are each a bonding group; and Y1 and Y2 are each a group combining -CONH- with COOH through a <=6 or 5-atomic group to obtain a liquid developer contg. a copolymer. This copolymer has electrostatic charge controlling function, and sharp images can be obtained after making a large number of copies, and this developer can be used for an offset printing plate with advantage.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a developer for electrostatic latent images, and more specifically, it relates to a developer for developing electrostatic latent images. The present invention relates to an improved liquid developer for converting into images. This improved developer is particularly suitable for developing electrostatic latent images on insulating surfaces with positively charged toner particles.

(Prior Art) In the process of electrophotography, for example, the surface of a recording material, such as one in which a photosensitive layer made of photoconductive zinc oxide is provided on a relatively highly conductive support, is uniformly coated in a dark place. is negatively charged. By projecting the optical image of the original image onto the charged photosensitive layer, a uniform partial discharge is generated on the charged surface depending on the intensity of the irradiated light, and the electrostatic latent image is to form ゛.

A visible image is created by applying electroscopic toner particles to this electrostatic latent image. This visible image is fixed directly to the photoconductive surface in the Nilecrodrofax method.

Alternatively, the electrostatic latent image or visible image is transferred and fixed onto the surface of a desired support through a transfer process such as charge transfer, suppression transfer, or magnetic transfer.

Further, in normal copying, it is required to obtain a positive copy from a positive original. Therefore, when the surface of the photosensitive layer is used with a negative charge, the electrodetectable toner particles are required to have a strong and stable positive charge. A liquid developer comprising positively charged toner particles is
Many types are already on the market.

However, all of these commercially available developers are designed for copying line or halftone image originals and are not suitable for continuous tone image reproduction. In other words, when a continuous tone image is copied using these developers, sufficient image density cannot be obtained, running defects (so-called streaks) are likely to occur in the image, and furthermore, non-image areas may be affected. It was found that toner deposition (fogging) was likely to occur.

In order to improve these problems and obtain good continuous tone images, a semi-alkylamide compound of diisobutylene-maleic acid copolymer is used as a charge control agent as a developer. Publication (U.S. Patent No. 110
6.27r), etc.

However, according to the experimental results of the present inventors, the positive charge of the toner particles in the developer is strongly maintained and there is no change in polarity. Develop at 7,000 yen while replenishing this developer as needed.
It has been found that when the copying machine is used repeatedly for many times, the sharpness of the obtained copy image gradually decreases. This has resulted in the problem that the amount of toner particles adhering to the image surface is reduced, causing the above-mentioned drawbacks and that the strength of the formed image after fixing is not sufficient. Therefore, when these developers are used to form images on zinc oxide photosensitive paper and used as offset printing plates, problems arise in that the oil sensitivity to printing inks and the number of printing sheets are insufficient.

Furthermore, the quality of the copied image obtained through the transfer process was also significantly degraded.

(Objective of the Invention) The present invention aims to improve the problems of the conventional liquid developer as described above.

An object of the present invention is to provide an excellent liquid developer that provides excellent image quality with good continuous tone images and does not cause image quality deterioration such as a decrease in density, lack of thin lines, or increase in fog even when used continuously for a long time. The goal is to provide the following.

Another object of the present invention is to provide a liquid developer that enables the continuous production of a very large number of offset printing plates by electrophotography, which have excellent printing ink sensitivity and printing durability. .

Another object of the present invention is to provide a liquid developer suitable for various types of electrostatic photography and various types of transfer such as charge transfer in addition to the above-mentioned uses.

(Structure of the Invention) The present invention has an electrical resistance of io Ω・α or more and a dielectric constant of 3
．． A monomer capable of polymerizing in the non-aqueous solvent to form a soluble polymer in an electrostatographic liquid developer in which a toner containing at least a resin as a main component is dispersed in a non-aqueous solvent as follows: It is characterized by containing a copolymer consisting of at least 7 or more types of (A) and a monomer (β) represented by the following general formula CI) or a monomer (C) represented by the following general formula (II). This is a liquid developer for electrostatic photography.

General formula (I) cH=c or -COOL(
L represents a hydrocarbon group), Xl represents an unsaturated bond group and -CON)l-? The atomic groups to be connected, and Y1 is -CON
Each represents a group that connects H- and -COO)T within the number of atoms. Also, without going through X1, -CON)1-Y
, 4:00) (may be directly bonded to the unsaturated bond group.

In formula (II), R3 and R4 are R1 and R in formula (1)
2, X2 represents an unsaturated bond group and -N)T
CO-'e represents an atomic group that connects, and Y2 represents a group that connects. Also, -N)TCO-y2- without passing through X2
COOH may be directly bonded to the unsaturated bond group.

The monomer (A) capable of forming a polymer soluble in a non-aqueous solvent constituting the copolymer of the present invention refers to monopolymerizable alkenes,
Cycloalkenes, styrenes.

Vinyl ethers, allyl ethers, vinyl esters or allyl esters of carboxylic acids.

These include esters of unsaturated carboxylic acids such as methacrylic acid, acrylic acid, itaconic acid, and maleic acid.

To explain further, the monomer has a total carbon number of t. Alkenes which may be substituted (e.g. hexene, octene, -monoethylhexene, decene, dodecene, tetradecene, hexadecene, octadecene, tocosene, eicosene,
10-hexyl undecenoate, ω-phenyl-l-propane, etc.), total carbon number! ~μQ optionally substituted cycloalkenes lJt cyclointene, cyclohexene,
Hisiclo [λ, 2-]-hebutene-24,! -cyanobicyclo [λ9.2. /]-hebutene-2, etc.), optionally substituted styrenes having a total carbon number of t to μO (e.g. styrene, 4t-methylstyrene, μ-n octylstyrene,
Hexyloxystyrene, etc.) aliphatic group-substituted vinyl ethers or allyl ethers having a total carbon number of 2 to 0% [an alkyl group that may be substituted as an aliphatic group (for example, a methyl group).

Ethyl group, butyl group, hexyl group, octyl group, decyl group, dodecyl group, hexadecyl group, octadecyl group, docosanyl group, chloroethyl group, λ-ethylhexyl group,
≠-methoxybutyl group, etc.), an optionally substituted aralkyl group (e.g., benzyl group, phenethyl group, etc.), an optionally substituted cycloalkyl group (e.g., cyclo is a methyl group, s'/C1hexyl group, etc.), or , optionally substituted alkenyl & (e.g., tbano-4-tenyl group, μm propyl-2-pentenyl group, oleyl group, lylyl group, etc.)
etc.], aromatic group-substituted vinyl ethers or allyl ethers having a total carbon number of 6 to ≠0 (e.g., phenyl group, ≠-butoxyphenyl group, goo-octylphenyl group, etc.).

Vinyl esters or allyl esters of optionally substituted aliphatic carboxylic acids having a total number of carbon atoms of t-μ0 (e.g. caproic acid, capric acid, lauric acid).

esters of myristic acid, /ξluminic acid, stearic acid, oleic acid, sorbic acid, linoleic acid, etc.), vinyl esters or allyl esters of aromatic carboxylic acids with a total number of carbon atoms exceeding Benzoic acid, co-butylbenzoic acid m, a- to *esters of siloxybenzoic acid, etc.)% or total carbon number a-po of unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, crotonic acid, etc. Examples include optionally substituted aliphatic group esters (eg, methyl group, ethyl group, propyl group, hexyl group, decyl group, λ-hydroxyethyl group, N,N-dibutylaminoethyl group, etc.).

Next, the monomer (B) K represented by the general formula (I) which is copolymerized with these monomers will be explained. sR in general formula (I)
1 and R2 may be the same or different and may be a hydrogen atom, a methyl group, -COOH or (group, phenethyl group, etc.).

Xl represents a group that connects the polymer main chain and -CONH- with a carbon atom, which may be via a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom; to give more specific examples, (- C-)-(R, R' are hydrogen atoms, alkyl groups, bar-N)TSO2-1-N)ICON)T-, -NHcO
O.

-802-, -CO-s -o -, S -s -N
-R'' (R represents a hydrogen atom, an alkyl group, etc.).

In addition, Yl represents a group that connects -CON)I- and -COO)( with up to a carbon atom, which may be through a heteroatom such as an oxygen atom, a nitrogen atom, or an ionic atom. %
C-CONH-yl-COO) without passing through X1
J) may be directly bonded to the polymer main chain.

Furthermore, the general formula (n
) In general formula (II), R3 and R4 are R1 and R2 of formula (I)
represents the same symbol as , and X2 represents an unsaturated bond group and -NH
CO- is an oxygen atom.

X
Represents the same thing as l. Y2 is -N) (CO- and -CO
represents a group that connects ON and up to 5 carbon atoms, which may be via a heteroatom such as an oxygen atom, a nitrogen atom, or a sulfur atom.

In addition, [-NHCO-Y2-CO
O)I) may be directly bonded to an unsaturated bond group.

Each monomer represented by the above general formula (I) and general formula (II) will be more specifically exemplified, but is not limited to the following compound examples.

(1) CH3 CH2=c C0NHC)T2COO)T (2) CH3 cH2=c C0NHC)ICOOH ■ 6H13 (3) CH3 ■ C) I=C) J Sad CH3 co2==[ C0NHCCHz)4COOH (5) (6 ) C) 13 CH3 1 Ql) t”H2,=cH 0CO(CH2)2CONH(CH2) 2cOOH(
11) CH2=C)( CH20CO(CH2)2CONHCI(2COOHI
Js 3 CH3 (14 CH,2=CH (CH2)4CONH(CH2)3COO)T(le CH2=CH COO(CHz )2NHCOCH2COOHaη c)12=cl(C)12NHCO(C)T2)2COOI(Q (11 c H2,: C) (NHCO(CHz)acOO)1 In order to produce the above-mentioned soluble copolymer resin used in the present invention, the above-mentioned monomer (A) and the monomer are generally combined. CB) or monomer (C) in an organic solvent,
In the presence of a polymerization initiator such as benzoyl peroxide, azobisisobutyronitrile, butyl lithium, etc.
At izo'c.

What is necessary is to carry out the reaction for a certain period of time.

In the present invention, by further adding other monomers to the reaction system and carrying out the polymerization reaction, ternary or more copolymerization can be achieved. It can be done. In any case, monomer (A) and monomer (B) 4
Alternatively, the composition ratio with the monomer (C) is 1O:RIO to Tata#:0. jC weight ratio), preferably 30Nia0~
yo:i.

(weight ratio). Moreover, the molecular weight of the copolymer is 1000~
Ioo, preferably zooo~! It is 00,000.

Specific examples of the copolymers obtained as described above are shown below, but the content of the present invention is not limited thereto.

(a) (b) CH3CH3 1 COOC18)T37 C0NHCH-(,”0086
H13 (c) CH3 ■ (f) CH3 It has been found that the above-described soluble resin of the present invention adjusts the electrodetectable toner particles in the liquid developer to a strong and stable positive charge. Furthermore, the aforementioned Tokko Sho≠2-JAt
Compared to the diisobutylene-maleic acid semi-alkylamide compound described in the Rino publication, the liquid developer using all the compounds of the present invention has a dramatically increased number of times of development and is also stable even when stored for a long period of time. They found that there was almost no change in performance.

Used in the present invention. Electrical resistance is IO-me or more.

Dielectric constant is 3. ! As the following nonaqueous solvent, preferably linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, or the like can be used. Preferred in terms of volatility, stability, toxicity, odor, etc. are octane, isooctane, decane, isodecane, nonane, dodecane, isododecane, decalin, isoparaffin-based petroleum solvents such as Isopar E, Isopar G, Isopar H, Iso, e-L (trade name of Exxon Corporation), Shell Silua/ (trade name of Shell Corporation), Amsco OMS, Amsco ato (trade name of Spirits Corporation), etc. are used alone or in combination.

The toner particles used in the present invention are not particularly specified; conventionally known toner particles can be used. For example, the resin that is the main component of the toner particles may be any resin that is substantially insoluble in the organic solvent, such as acrylic resin, ester resin, amide resin, alkylene IUIL, phenol-modified alkyd resin, and epoxy resin. , rosin, synthetic rubber, and other synthetic or natural resins.

The resin dispersion that can be used in the liquid developer is
It can be produced according to a known method.

For example, a desired resin is dispersed in a non-polar solvent.

There is a method of manufacturing by kneading with a ball mill or high-speed stirrer. In addition, for monomers, a so-called polymerization granulation method is known in which a monomer that is dissolved in a nonpolar solvent and polymerized to become a resin becomes insoluble in the solvent is polymerized to obtain a resin dispersed in the solvent. It is being for example.

K., E., and Barrett, “Dispersio.
nPolymerization in Organi
c MediajJohn Willey and 5
ons, London.

127≠, U.S. Patent No. JGJ7jA, U.S. Patent No. 3
It can be produced according to the method described in No. 713760 and the like.

The particle size of the resulting dispersed resin product is! It is desirable to have a diameter of less than microns, especially less than 2 microns, in order to obtain a continuous tone image.

The coloring agent, which is the other main component of the toner particles, is not particularly specified; any conventionally known pigment or dye can be used. The colorant may be used alone or dispersed in the non-aqueous solvent in combination with a dispersion accelerator, etc., or it may be used by dispersing it in the non-aqueous solvent in combination with a dispersion accelerator, etc., or it may be used as a graft-type particle (te IJ mom) chemically bonded to the surface of the colorant. For example grafted carbon:
(Product name manufactured by Mitsubishi Gas Chemical Co., Ltd.) may also be used. A coloring agent may also be incorporated into the above-mentioned resin.

As a method for coloring the dispersion resin, for example, Japanese Patent Application Laid-Open No.
Dispersion machine (paint shaker, colloid mill, vibration mill) which is a known method such as J, 244u, etc.

There is a method of physically dispersing it in the resin using a ball mill, etc., and there are many known pigments and dyes.For example, magnetic iron oxide iron powder, carbon black,
Examples include nigrosine, alkali-dull, Hansa yellow quinacridone red, futa, russianine-dull, phthalocyanine black, and benzidine yellow.

Another method for coloring is to thermally dye a monodispersed resin material with a preferred dye, as described in JP-A-17-4'173.

Examples include Hansa Yellow Crystal Violet, Victoria Blue, Malachite Green, Seriton Fast Red, Desperse Yellow, Tesno ξ-Thread, Desperse Sprue, and Solvent Red.

Still another method of coloring is a method of chemically bonding a dispersion resin and a dye. For example, JP-A-Shojj-jtlAO
In the second method, a method of reacting a resin and a dye, or
A method is known in which a dye is previously bonded to a resin monomer that can be made insolubilized and dispersed by polymerization, and these methods can be used.

In order to stably disperse the above-mentioned resin or colorant in the non-aqueous solvent, a conventionally known dispersion stabilizer can be used. That is, various synthetic resins or natural resins can be used alone or in combination of two or more. For example, an alkyl chain having a total carbon number of μ to 30 [may contain substituents such as halogen atoms, hydroxyl groups, amino groups, alkoxy groups, etc., or carbon-carbon atom bonds in the main chain with hetero atoms such as oxygen atoms] alkyl esters of acrylic acid or methacrylic acid, vinyl esters of fatty acids, or vinyl alkyl ethers or tutadiene, isoprene.

Polymers of monomers such as olefins such as diynbutylene, or copolymers of two or more in combination.

Copolymers of monomers forming polymers soluble in aliphatic hydrocarbon solvents as described above and one or more of the following various monomers can be used.

For example, vinyl acetate, acrylic acid, or methacrylic acid,
Crotonic acid methyl, ethyl, n-pyl acetate
s o-propyl ester, styrene, vinyltoluene, α-methylstyrene derivatives, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, or their anhydrides, hydroxyethyl acrylate, Diethylaminoethyl methacrylate SN-vinylpyrrolidone, acrylamide.

Acrylonitrile, λ-chloroethyl methacrylate 1
．． 21λ, 2-) Hydroxy group, amino group, amide group, such as lyfluoroethyl methacrylate.

Examples include monomers containing various polar groups such as cyano groups, sulfonic acid groups, carbonyl groups, halogen atoms, and heterocycles.

Alternatively, in addition to the synthetic resins mentioned above, alkyd resins and alkyd resins modified with various fatty acids.

Resins such as linseed oil modified polyurethane resins can also be used.

The amounts of each main component of the liquid developer of the present invention are explained below.

The toner particles mainly composed of resin and colorant contain 0.1 parts by weight or more per 1,000 parts by weight of the carrier liquid! O parts by weight are preferred. If it is less than 0.1 parts by weight, the image density will be insufficient, and if it is more than 0.1 parts by weight, fogging will tend to occur in non-image areas. A carrier liquid soluble resin such as the above-mentioned dispersion stabilizer is also used if necessary, and can be added in an amount of about 0.2 parts by weight to 100 parts by weight based on 7000 parts by weight of the carrier liquid.

The novel compound of the present invention, which is a charge control agent, produces a remarkable effect in a very small amount on the carrier liquid, and the best amount is 0.00/0.1 parts by weight per 100 parts by weight of the carrier liquid.

Below this lower limit, the positive charge retention of the toner particles becomes unstable, while above the upper limit, the electrical resistance of the developer decreases, resulting in a lower image density.

Various other additives may be added as necessary. For example, specific examples are given in Yuji Harasaki, "Electronic Photography", Vol. 74, No. 2, p. Dahiro. The upper limit of the total amount is regulated by the electrical resistance of the developer. That is, if the electrical resistance of the liquid developer with toner particles removed becomes less than io Ω·a, it becomes difficult to obtain a high-quality continuous tone image, so the amount of each additive added should be determined.

It is necessary to control within this limit.

Examples of the present invention are presented below, but the present invention is not limited thereto.

Soluble Resin Production Example 1: Specific Example (a) A mixture of stearyl methacrylate 3o, Ag, N-carboxymethylmethacrylamide r, tg, toluene log and methanol λOg was heated to a temperature of 700C while stirring under a nitrogen atmosphere.

At that temperature, 0.11 j of azobisisodutyloethryl was added and stirred for 3 hours, and further azobisisobutyronitrile O1≠gt- was added and stirred for 3 hours. After cooling, the reaction solution was added to 200M methanol with stirring for 30 minutes, and the mixture was further stirred for 1 hour. Sediment ftF collection・
After drying, 31 g of white solid was obtained.

The weight average molecular weight measured by high performance liquid chromatography was 3 x 10.

Soluble resin production example 2: Specific example (c) Stearyl methacrylate 3o, 4. fil, N-(cocarboxyphenyl)methacrylamide 12, J9.
) A mixture of 100% toluene and 309% ethanol was stirred under a nitrogen atmosphere at a temperature of 7! Ocrc was heated. At that temperature, 0 tg of benzoyl peroxide was added and stirred for 3 hours, and then 0.0 tg of indiyl peroxide was added. Add El/f and μ
Stir for hours. After cooling, 1 reaction solution was mixed with methanol.
t while stirring for 30 minutes, then add another 1
Stir for hours. Collect the precipitate tF and dry it to form a white solid JJ
I got 1if.

The weight average molecular weight measured in the same manner as in Production Example 1 was Hiro!
×10 Atsushi.

Example 1 Poly(lauryl methacrylate) 71g% vinyl acetate 1
A mixed solution of 009 and isododecane Jlrjf/ was heated to a temperature of 70°C while stirring under a nitrogen stream. Ko,
λ'-Azobis(isobutylnitrile)/71 was added and reacted during the day, and then cooled.

Passed through λOO mesh nylon cloth.

A white resin dispersion with a polymerization rate of 13% and an average particle size of o and it μm was obtained.

10g poly(lauryl methacrylate), 1 nigrosine
0 g and 30 g of isododecane were placed in a paint shaker with glass beads and dispersed for 2 hours to obtain a fine dispersion of nigrosine.

32g of the above white resin dispersion, the above nigrosine dispersion,! g, polymer o obtained in resin production example 1, ot
A liquid developer for electrostatic photography was prepared by dispersing it in g-@indodecane il.

The obtained liquid developer was transferred to Fuji fully automatic plate making machine ELP2ZO (
Using ELP master (manufactured by Fuji Photo Film) as an electrophotographic photosensitive material for printing masters, an image is formed on the ELF master from a positive original with continuous gradation to create a master. Get a plate.

The resulting master plate image is a good continuous tone image, and the maximum optical density of the image is /,! /, the minimum (fog) was 0.01. The color tone of the image was warm. Similarly, 2000 ELP master sheets are processed and 20
When I checked the optical density of the image on the 00th master plate, the maximum was 1.

(at), there was little decrease in concentration, and the minimum was 0.0t, with no change. Also, the first processed and 200
When the 0th image was observed, all images were very clear.

Next, the non-image areas of the seventh and 2000th master plates were desensitized, and each was used as a printing plate, and 3000 sheets were printed. No matter which plate was used, the 3,000th print was clear, with no broken thin lines, and no fog.

(Comparative Example A) In the preparation of the liquid developer of Example 1, the following polymer (A) was used instead of the polymer [charge control agent] of Resin Production Example 1 of the present invention.

A liquid developer for electrostatography was prepared in the same manner as in Example 1.

Polymer (A) Copolymer composition ratio: 7/J (molar ratio) The obtained liquid developer was tested in the same manner as in Example 1, and when the image on the first master plate was observed, it was found that the solid area and It was a book whose image parts were impossible to identify. This was due to the fact that the toner particles in the liquid developer used had no electrodetection properties.

From the above results, in order to maintain positive charge in toner particles, one method is to use the compound of the present invention.

[-CON)I-] or [-N)ICO-] and (-CO
OH] are required to be close to each other within the number of atoms.

Examples 2 to 6 In preparing the liquid developer of Example 1, a liquid developer for electrostatography was prepared in the same manner as for the polymer (charge control agent) of Resin Production Example 1 of the present invention.

For comparison, a sample was also prepared using a known charge control agent, diisobutylene-maleic acid half-octadecylamide copolymer. The obtained liquid developer was tested in the same manner as in Example 1, and the maximum density of the image on the first master plate and the maximum density of the 2000th master plate in the same image area were measured. The rate of change was determined by the following 2.

As is clear from Table 7, in Examples 2 to 5 in which the polymer of the present invention was used, the maximum image density of the obtained master plates was high, and there was little decrease in density even after processing 500 sheets. However, in Example 6, which was carried out for comparison, the master density on the 7th sheet was high, but the density on the 2000th sheet was greatly reduced, and the printed matter printed using this had noticeable breaks in the fine lines of the printed image. Fog was observed in the non-image area (20
0.10al) has been increased from the first one fc).

Example 7 To 700 g of the white resin dispersion obtained in Example 1, finely powdered Sumikalon Navy Blue (manufactured by Sumitomo Chemical ■) zy was added and stirred at a temperature of 1000C for 5 hours. %20 after cooling
A blue resin dispersion was obtained through a 0 mesh nylon cloth. This material has an average particle size of 0. /Ittm resin.

A liquid developer was prepared by dispersing 31 g of the blue resin dispersion described above and 0.01 Aj9 of the polymer obtained in Resin Production Example 2 in 1 l of isodecane.

Using this liquid developer, a test was conducted according to the method described in Example 1.

The images obtained from the first master plate and the 2q00th master plate are good continuous tone images, and the maximum optical density of the images is fL/, ≠
O and/or 31. Moreover, the minimum (fog) was 0.01 in both cases.

3000 copies of each of the 7th and xoooth master plates were printed using the conventional method.

Even after printing 3000 sheets, clear printed matter could be obtained.

Claims (1)

[Claims] Electrical resistance is 109Ω・α or more and dielectric constant is 3°! In an electrostatographic liquid developer in which a toner containing at least a resin as a main component is dispersed in the following non-aqueous solvent, a monomer capable of polymerizing in the non-aqueous solvent to form a total soluble polymer is added. An electrostatic photographic liquid developer characterized by containing a copolymer consisting of at least seven or more species and a monomer represented by the following general formula CI) or a monomer represented by the following general formula (If) agent, general formula (I) cH=c x 1-CON) (-y 1-COo) 1 general formula (II
) C) (=C
L represents a hydrocarbon group), Xl represents an atomic group connecting an unsaturated bond group and -CONH-, and Yl represents -CONH-
) Each represents a group that connects T- and -COOH with up to 6 atoms. Moreover, -CON)1- without passing through Xl
Yl-COOH may be directly bonded to the unsaturated bond group. In formula (II), %R3 and R4 are R in formula CI). and represents the same symbol as R2, and X2 represents an unsaturated bond group and -
The atomic group connecting NHCO-, and Y2 is -Nf(C
Each represents a group that connects o- and -cooi-t using up to 5 atoms. Also, -NHCO-Y without going through sX2
2-COOH may be directly bonded to the unsaturated bond group.