JPH01173067A - Photoconductive toner - Google Patents

Abstract

PURPOSE:To obtain a photoconductive toner which exhibits photoconductivity with visible light by incorporating a polymer component having a rhodanine deriv. in the side chain of a chain high polymer. CONSTITUTION:The photoconductive toner is obtd. by incorporating the polymer component having the rhodanine deriv. expressed by formula I into the side chain of the chain high polymer and dispersing or compatibilizing a charge generating material into a fixing resin medium. The polymer has a rhodanine ring in the molecular chain and the quinoline group introduced via a 2-butyl diiridine group in the 5th position of the rhodanine group. The rhodanine ring part of the polymer is considered to be an electron acceptor and the quinoline group part to be an electron donor to form an intra-molecular charge transfer type complex, thereby forming the color. Carrier are generated by light absorption in a visible light region of the polymer so that the toner exhibits the excellent photoconductivity in the visible light region. In formula, R1 denotes a lower alkyl group of 1-6C, substd. or unsubstd. aryl group, hydrogen atom, hydroxyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a photoconductive toner, and more particularly to a photoconductive toner in which each particle has uniform photosensitive characteristics and coloring properties.

(Prior art) A typical image forming method applying electrophotographic technology is to visualize an electrostatic latent image formed on a photoreceptor with toner to form a toner image, and then print this toner image on plain paper. Examples include the xerography method, which obtains a copy by transferring the photosensitive material to a transfer material, and the electrofox method, which produces a copy by directly developing the photosensitive material, but all of these methods require a development step. The disadvantage is that the equipment for its implementation is complex and expensive.

To solve this problem, a photoconductive toner is uniformly deposited on a conductive substrate to form a toner layer, and this toner layer is charged and imagewise exposed to charge the photoconductive toner in the exposed area. An image forming method is known in which, after forming an electrostatic latent image by eliminating or weakening the electrostatic latent image, only the charged photoconductive toner in the unexposed area is transferred to the transfer material. The photoconductive toner used in this method is generally resin fine particles in which a photoconductive substance is dispersed together with a coloring agent in a binder resin. Organic photoconductors such as conductors, photoconductive polymers such as polyvinylcarbazole (PVC) and hydrazone, and low-molecular photoconductive compounds are used. In practical use, aggravating agents such as organic dyes and pigments are used together with photoconductors without reducing photosensitivity and sensitization to visible light.In this way, photoconductive toners have a high sensitivity to both hue and light. These are fine resin particles that have the functions of conductivity and photosensitivity, and in order to exhibit good development characteristics, each additive is uniformly dispersed in the binder resin and is present on the toner surface, so that each toner particle has the following functions: It is necessary to make the surface characteristics uniform.

(Problems to be Solved by the Invention) However, the components of the colorant, the photoconductor, and the pigment as a sensitizer are finely and uniformly dispersed in the binder resin of each toner particle and are present on the particle surface. It is difficult to
In particular, pigments as sensitizers tend to exist as aggregates in the binder resin, causing fine dispersion, making it difficult to make the development characteristics of individual toner particles constant. In the case of photoconductive color toners, the photoconductor and sensitizer also have the disadvantage that the toner has a poor hue, resulting in images that lack vividness.

Therefore, an object of the present invention is to provide a photoconductive toner that exhibits photoconductivity in visible light without containing a carrier-generating pigment as a sensitizer.

Another object of the present invention is to provide a photoconductive toner comprising as few components as possible and having uniform photosensitive characteristics of each particle.

Still another object of the present invention is to provide a photoconductive color toner with a vivid hue.

(Means and effects for solving the problem) (1) A rhodanine derivative of the following structural formula is regularly added to the side chain of a chain polymer (in the formula, R8 is a lower alkyl group having 1 to 6 carbon atoms, substituted or unsubstituted). The above-mentioned problems are solved by dispersing or dissolving a charge generating material in a fixing resin medium containing a polymer component having a substituted aryl group, a hydrogen atom, or a hydroxyl group to obtain a photoconductive toner, The objectives of the invention are achieved.

The polymer of the present invention has a rhodanine ring in its molecular chain and a quinoline group introduced at the 5-position of the rhodanine ring via a 2-butyldiylidene group. In the above polymer, the rhodanine ring portion is considered to be an electron acceptor, and the quinoline group is considered to be an electron donor, forming an intramolecular charge transfer type complex to develop color.

That is, when the π electrons delocalized in the electron donor in the ground state are transferred to the empty orbit of the electron acceptor through the group r=C=CH-CH=J, light energy is absorbed and color is generated.

The polymer according to the present invention generates carriers by absorbing light in the visible light region, and exhibits excellent photoconductivity in the visible light region without requiring the addition of a sensitizer. Furthermore, as mentioned above, the polymer of the present invention has good photoconductivity because it regularly has polymerized units containing a rhodanine derivative2, and it can be used to form toner particles by dispersing or dissolving the polymer in a fixing resin medium. A photoconductive toner in which each particle has uniform photosensitive properties can be obtained by simply oxidizing the particles.

Further, the polymer of the present invention itself exhibits a bright blue color, and a photoconductive color toner can be obtained without containing a colorant.

(Preferred correspondence of the invention) The i-form of rhodanine used in the present invention has the following general formula, S (where B is a reactive substituent, (C) is a divalent organic group, and R is a lower alkyl group, hydroxyl group). Examples of C include alkylene groups having 4 or less carbon atoms, arylene groups such as phenylene groups, and carbonyloxyalkylene groups such as carbonyloxyethyl and carbonyloxypropylene groups.

Examples of alkyl groups for R include lower alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, and hexylyl groups, and examples of aryl groups that may have substituents include phenyl, naphthyl, anthryl, Examples include phenanthryl and fluorenyl, and examples of substituents include lower alkyl groups having 1 to 4 carbon atoms, alkoxy groups such as methoxy, ethoxy, and propoxy, amino groups, dimethylamino,
Examples include alkylamino groups such as diethylamino and dipropylamino groups, and halogen atoms.

in particular, can be raised.

As shown in the above specific example, the reactive substituent B is -C
Examples include OOH-CH2C1-OH-COCI-Nl2.

These rhodanine derivatives can be synthesized by various methods, such as the following reaction formula.

(In the formula, B, (C), p, and R are the same as above.) That is, rhodanine M is obtained by reacting 3-substituted rhodanine and 2-β-acetanilide vinylquinoline alkyl iodide in alcohol. Can be done.

In order to obtain a polymer having rhodanine derivatives regularly in side chains, the radically polymerizable monomer to which the rhodanine derivative is bonded is easily produced by polymerizing in the presence of a radical initiator. be able to.

The radically polymerizable monomer having a substituent having reactivity with the rhodanine derivative to become the radically polymerizable monomer bonded with the rhodanine derivative is, for example, the following general formula 〇H,... CH (CH,).

An olefinic monomer represented by Nl2 (in the formula, m represents an integer of O to 3), the following general formula, CH2=CH (in the formula, R2 is -CH2Cl, -Nl2, -so□C1,
-COOH), a styrenic monomer represented by the following general formula: R8 represents a hydrogen atom or a methyl group, and m is the same as above) An acrylic or methacrylic monomer is exemplified.

The reaction between the monomer and the rhodanine derivative is achieved, for example, by the following reaction formula.

S C00H11 S As the alkali used in these reactions, pyridine, triethylamine, etc. are used.

These monomers can be mixed with azo compounds such as azobisisobutylnitrile, benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, lauroyl peroxide, etc. in solvents such as tetrahydrofuran, benzene, dimethylformamide, and dichloromethane. Polymerization can be easily carried out by heating in the presence of a radical initiator such as peroxide.

The radical initiator concentration was 0°1 per 484 bodies.
It is preferable that it is 10% by weight. The polymerization temperature varies depending on the type of radical initiator used, but is usually 2
0 to 100°C is preferred. , and the polymerization time is 1 to 5
0 hours is preferred. The weight average molecular weight of the obtained polymer can be adjusted within a wide range of 10,000 to 40,000 by selecting the monomer concentration, radical initiator concentration, and polymerization temperature.

As the resin medium for fixing in which the above polymer is blended, resins used in the manufacturing method of this type of toner are used, and particularly preferred ones include various mono- or diethylene-based unsaturated monomers. (a) vinyl aromatic monomer,
(b) Homopolymers, copolymers, etc. of acrylic monomers are used.

Examples of the monomer (a) above include styrene, vinyltoluene, α-methylstyrene, α-chlorostyrene, vinylxylene, vinylnaphthalene, etc.
Monomers (b) include methacrylic acid, ethyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate,
2-ethylhexyl methacrylate, 3-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 3-aminopropyl acrylate, 3-N,N-
Examples include diethylaminopropyl acrylate and acrylamide.

Other monomers used in combination with these monomers (a) or (b) or alone include butadiene,
In addition to isoprene, chloroprene, etc., maleic anhydride,
Other ethylenically unsaturated carboxylic acids or their esters such as fumaric acid, crotonic acid, itaconic acid, vinyl esters such as vinyl acetate, vinylpyridine, vinylpyro,
Examples include lydone, vinyl ethers, acrylonitrile, vinyl chloride, and vinylidene chloride. The molecular weight of these resins is preferably in the range of 3,000 to 300,000, particularly 5,000 to 200,000.

When the aforementioned polymer of the present invention is used in an amount of 50 to 200 parts by weight per the fixing resin medium, a toner with good photosensitivity, photoconductivity, and fixing properties can be obtained.

Furthermore, the polymer of the present invention can be directly contained in the fixing resin medium by copolymerizing the radically polymerizable monomer having the rhodanine derivative described above with the monomer serving as the fixing resin medium.

Further, when the toner is a heat fixable toner, the softening point of the polymer is 50 to 200°C, preferably 70 to 200°C.
One having a temperature of 170°C is preferred.

With the polymer of the present invention to increase photoconductivity in visible light,
A charge transport material may be used, and as the charge transport material to be added, known electron transport substances and hole transport substances can be used. Specifically, electron-accepting substances having an electron-accepting group such as a nitro group, a nitroso group, or a cyano group, such as fluorenone-based compounds such as tetracyanoethylene, 2,4.7-)limtro-9 fluorenone, and dinitroanthracene , 2.4.8-trinidrothioxanthone, and other nitro compounds; electron-donating substances such as N, N-
Diethylaminobenzaldehyde N, N-diphenylhydrazone, N-methyl-3-rubazolaldehyde
Hydrazone compounds such as N,N-diphenylhydrazone, 2,5-di(4-N,N-dimethylaminophenyl)
-1゜3.4-oxadiazole, 2.5-di(4-N
.

Oxadiazole compounds such as N-diethylaminophenyl)-1,3,4-oxadiazole, schel compounds such as 9-(4-diethylamistyryl)anthracene, carbazole compounds such as N-ethylcarbazole, l -Phenyl-3-3(4-dimethylaminophenyl)pyrazoline, 1-phenyl-3-(4-dimethylaminostyryl)-5-(4-dimethylaminophenyl) birapurine, 1-phenyl-3-(4-diethylamino Pyrazoline compounds such as styryl)-5-(4-diethylaminophenyl)pyrazoline, 2-(4-diethylaminophenyl)-4-(4-dimethylaminophenyl)-
Oxacin compounds such as 5-(2-chlorophenyl)oxazole, isoxazole compounds, thiazole compounds such as 2-(4-diethylaminostyryl)-6-dinithylaminobenzothiazole, triphenylamine, 4.4-bis (Amine derivatives such as N-(3-methylphenyl)-N-phenylaminocobiphenyl, stilbene compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, indole compounds,
Nitrogen-containing cyclic compounds such as triazole compounds, fused polycyclic compounds such as anthracene, pyrene, phenanthrene,
Examples include poly-N-vinylcarbazole, polypropylene, polyvinylanthracene, and ethylcarbazole-formaldehyde resin. One or more of the above charge transport substances are used, and are added to the polymer in consideration of the fixing properties and cohesive properties of the toner.
0 to 50 parts by weight, preferably 30 to 40 parts by weight are used.

In addition, examples of colorants that color the photoconductive toner black or other hues include carbon black, lamp black (C, 1, No. 77266), and chrome yellow (
C, I, No, 14090), Hansa Yellow (C
, 1, No. 11660.11680, etc.), benzidine yellow (C, 1, No.

21100 etc.), Suren Yellow G (C, I, N
o, 70600), quinoline yellow (C, 1, No.
, 47005), Permanent Orange GTR (C, 1
, No. 12305), Plasticine Orange (C, 1,
No. 21160), Watch Young Red (C, 1,
No.

15868), permanent red (C, 1, No, 1
23LO, etc.), brilliant carmine 3B (C, 1, N
o, 16105), brilliant carmine 6B (C,
1, No. 15850), DuPont Oil Red (C
, 1, No. 26105), Pyrazolone Red (C.

1, No. 21120), Lysole Red (C, 1, N
o, 15630), Rhodamine B Lake (C, 1, No.
, 45170), Lake Red C (C, 1, No. 4
5435), Aniline Blue (C, 1, No.

77103), Calco Oil Blue (C, 1, No, a
zoec Blue3), methylene blue chloride (
C, 1, No. 52015), Phthalocyanine Blue (
C,1, No. 74260), malachide green oxalay) (C,1, No. 42000), etc., or nigrosine dye, Subiron black, etc., and C,1,S.

1vent Yellow 60, C, 1,5ol
vent Red 27, C, 1, S.

1vent Blue 35, C, 1,5olven
t Green 15, C, 1, S.

Examples include oil-soluble dyes such as 1vent Brown 5, and oil-soluble dyes are particularly preferred from the viewpoint of photoconductivity and colorability.

These colorants may be used singly or in combination of two or more, for example, 1 to 30 parts by weight, preferably 2 to 20 parts by weight, per 100 parts by weight of the binder resin.

Note that in order to control the charge of the toner as necessary, the above toner may contain a charge control agent such as nigrosine dye (C, 1, No. 50415B) and oil black (C, 1, No. 50415B) as other additives. , 26150), oil-soluble dyes such as Spiron black, and metals such as naphthenic acid, salicylic acid, octylic acid, fatty acids mentioned below, and metal salts of resin acids such as manganese, iron, cobalt, lead, zinc, cerium, calcium, and nickel. In addition, the above-mentioned toner may contain an offset inhibitor, such as a low molecular weight polypropylene, to prevent the toner from adhering to the fixing roller.
Low molecular weight polyethylene, various waxes such as paraffin wax, low molecular weight olefin polymers of olefin monomers having 4 or more carbon atoms, fatty acid amides, silico,
If necessary, the toner may be surface-treated with an external additive such as a silane coupling agent, silicone, or a fluorine compound in order to improve the fluidity of the toner.

Further, the method for producing a photoconductive toner of the present invention includes mixing a chain polymer having a rhodanine derivative in its side chain, a charge transporting material, and optionally a coloring agent and other additives.
After kneading, this is pulverized. Alternatively, a toner having a particle size of 5 to 50 μm is produced by mixing and dispersing the mixture in a suitable solvent and spray-drying the resulting solution.

For image formation using the toner of the present invention, in addition to metal plates such as aluminum plates and tin plates and drums thereof, transparent conductive substrates such as Nesa glass are used. Any means known per se can be used to form the toner phase on the substrate, for example by mixing the toner composition described above with a magnetic carrier to form a two-component composition, which The magnetic brush is supplied onto a sleeve having a magnet therein, and the magnetic brush rubs against the conductive substrate to form a toner layer on the substrate. Further, the charged toner is supported on a Noah brush, and the conductive substrate is rubbed with the brush, thereby forming a toner layer on the substrate. In this case, if a bias voltage is applied between the conductive substrate and the sleeve or fanaprush, the toner layer can be formed more easily.

The toner layer formed on the conductive substrate has already been charged itself, but if necessary, it may be forcibly charged using a corotron or the like. The thickness of the toner layer is such that toner particles are formed in one layer to several layers, and the coating amount is 8 to 50 g/m'' in terms of weight per unit area.

Image exposure includes uniform exposure of the entire surface using a flash lamp,
This can be performed by slit exposure using a halogen lamp or the like. The exposure amount varies greatly depending on the sensitivity of the photoconductive toner, but it ranges from 50 to 2001 ux-se at -g.
The range c is the mortgage.

As the transfer means, corona discharge transfer or roller electrode transfer, which are known per se, can be used, and the fixing operation can be performed using a per se known coercive heat roller in a heater or an oven heater.

Generally, a suitable fixing temperature is in the range of 160 to 200°C.

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

(Example 1) [Synthesis of rhodanine] Synthesis of 3-carboxymethyl-5-(2-(1-ethylquinoline)dimethine)rhodanine 19.1 g of 3-carboxymethylrhodanine and 2-β-acetanilide The above compound was obtained by refluxing 46.6 g of vinylquinoline ethiodide and 12.1 g of triethylamine in ethanol for 930 minutes, and recrystallizing the product from pyridine (yield: 4
9%).

[Synthesis of monomer having rhodanine derivative] 15.2 g of P-chloromethylstyrene, 37.2 g of 3-carboxymethyl-5-(2-(1-ethylquinoline)dimethine) rhodanine obtained above and 16 ml of triethylamine were added. Dissolve in 79ml of dimethylformamide and react at 90"C for 3 hours.

After the reaction, the reaction solution was poured into water, the resulting precipitate was washed with water, and recrystallized with acetone to obtain the above monomer.

[Solution polymerization]

Add α to 4.3 g of the monomer obtained above as a polymerization initiator.
, 6 mg of α゛-azobisisobutyronitrile and 5 ml of tetrahydrofuran as a solvent were added, the above mixture was dissolved and sufficiently dispersed, and then charged into a polymerization tube and degassed several times to seal the tube and create an ampoule in a vacuum state. did. This was reacted for 300 hours in a 60°C constant temperature bath to obtain 4.0 g of the polymer of the present invention.

[Manufacture of toner]

Thoroughly mix and disperse a solution consisting of 100 parts by weight of a styrene-acrylic copolymer as a fixing resin, 90 parts by weight of polystyrene having the rhodanine derivative obtained above in its side chain, 2500 parts by weight of toluene and 500 parts by weight of THF as a solvent, A photoconductive toner having a center particle of 12 μm was obtained by a spray drying method. This toner is a toner having photosensitivity to red light around 650 nm. Next, the toner obtained above was mixed with an electrophotographic carrier (ferrite carrier, average particle size: 80 μm) and negatively charged (toner concentration: 8%). When this toner was deposited on an aluminum substrate and an image was formed using red light, a bright blue image was obtained with no missing characters and no background fog.

(Example 2) ' 100 parts by weight of the polymer having the rhodanine derivative in the side chain obtained in Example 1, 90 parts by weight of styrene-acrylic copolymer, 40 parts by weight of 4-diethylaminobenzaldehyde 1,2-diphenylhydrazone as a charge transport material. parts by weight, 25 parts by weight of spironoblack, 2500 parts by weight of toluene as a solvent
A solution consisting of 50 parts by weight of THF and 50 parts by weight of THF was thoroughly mixed, and a photoconductive toner having a center particle size of 11 μm was obtained by spray drying.

The above-obtained toner and electrophotographic carrier (ferrite carrier, average particle size 80 μm). This toner was deposited on an aluminum substrate and imagewise exposed to white light to obtain a black toner image corresponding to the original image. The obtained image was clear with no background fog.

(Example 3) [Synthesis of rhodanine] Synthesis of 3-amino rhodanine 5- (2-(1-ethylquinoline)dimethine) rhodanine 17.3 g and 45 g of 2-β-acetanilide vinylquinoline ethiodide゜2g1 12.4g of triethylamine was refluxed in ethanol for 30 minutes, and the product was recrystallized from pyridine to obtain the above compound.

[Synthesis of monomer having rhodanine derivative] 10.5 g of methacrylic acid chloride and 3-amino-5 obtained above
-(2-(3-ethylbenzthiazoline)dimethine) 32.9 g of rhodanine is dissolved in 100 ml of dimethylformamide and reacted at 80° C. for 3 hours.

After the reaction, the reaction solution was poured into water, the resulting precipitate was washed with water, and recrystallized with acetone to obtain the above monomer.

[Solution polymerization]

Add α to 4.6 g of the monomer obtained above as a polymerization initiator.
, 6 mg of α°-azobisisobutyronitrile, ? 5 ml of tetrahydrofuran was added as a medium to dissolve and sufficiently disperse the above mixture, which was then charged into a polymerization tube and degassed several times to seal the tube and create an ampoule in a vacuum state. This was reacted for 300 hours in a constant temperature bath at 60° C. to obtain 4.5 g of the polymer of the present invention.

[Manufacture of toner]

A solution consisting of 100 parts by weight of a styrene-acrylic copolymer as a fixing resin, 100 parts by weight of polymethacrylic acid chloride having the rhodanine derivative obtained above in its side chain, 2500 parts by weight of toluene as a solvent, and parts by weight of THF5QO were thoroughly mixed. A photoconductive toner having a center particle of 11 μm was obtained by dispersing and spray drying. This toner is 6
This toner is sensitive to red light around 50 nm. Next, the toner obtained above was mixed with an electrophotographic carrier (ferrite carrier, average particle size: 80.crm) and negatively charged (toner concentration: 8%). When this toner was deposited on an aluminum substrate and an image was formed using red light, a bright blue image was obtained with no missing characters and no background fog.

(Example 4) [Synthesis of rhodanine] 3-(P-chloromethylphenyl)-5-(2-(1
-Methylquinoline)dimethine]Rhodanine synthesis 3-(P-chloromethylphenyl)rhodanine 19.3
g and 18.3 g of 2-β-acetanilide vinylquinoline methiodide were reacted in DMF at 100°C. 3
After a period of time, the reaction solution was added to water, and the resulting precipitate was washed with water.
The above compound was obtained by recrystallizing with acetone.

[Synthesis of monomer having rhodanine derivative] 8.5 g of methacrylic acid and the 3-amino-5-(2-(1
-Methylquinoline) rhodanine (39.5 g) dissolved in 12 ml of triethylamine in dimethylformamide lQ
Dissolve in Qml and react at 100°C for 3 hours.

After the reaction, the reaction solution was poured into methanol, and the resulting precipitate was reprecipitated with THF/methanol and dried under reduced pressure to obtain the above monomer.

[Solution polymerization]

Add α to 3.8 g of the monomer obtained above as a polymerization initiator.
, 5 mg of α゛-azobisisobutyronitrile
After adding 5 ml of tetrahydrofuran as a solvent to dissolve and sufficiently disperse the above mixture, the mixture was charged into a polymerization tube and degassed several times to seal the tube and create an ampoule in a vacuum state. 3.4g of this was reacted for 300 hours in a 60℃ constant temperature bath.
A polymer of the present invention was obtained.

[Manufacture of toner]

100 parts by weight of a styrene-acrylic copolymer as a fixing resin, 110 parts by weight of polymethacrylic acid having the rhodanine derivative obtained above in its side chain, and 20 parts by weight of 4-ni-diethylaminobenzalde-5-2-diphenylhydrazone as a charge transport material. A solution consisting of 2,500 parts by weight of toluene and 500 parts by weight of THF as a solvent was sufficiently mixed and dispersed, and a photoconductive toner having center particles of 10 μm was obtained by spray drying. This toner is a toner having photosensitivity to red light around 650 nm. Next, the toner obtained above was mixed with an electrophotographic carrier (ferrite carrier, average particle size 80 μm) and negatively charged (toner concentration 80 μm).
%). When this toner was deposited on an aluminum substrate and an image was formed using red light, a bright blue image was obtained with no missing characters and no background fog.

(Effects of the Invention) As is clear from the above examples, the photoconductive toner obtained by the present invention does not contain a sensitizer and exhibits excellent photoconductivity in the visible light region, so A photoconductive toner is obtained with the constituent materials, and a uniform dispersion of each additive in the toner is possible, resulting in uniform properties of the individual toner particles. Therefore, a clear image without background fog can be obtained during image formation.

In addition, since the binder resin is a photoconductor and does not turn bright blue, a photoconductive blue toner with excellent translucency can be obtained without containing a colorant.

Claims (2)

[Claims] (1) Rhodanine derivatives with the following structural formula are regularly distributed on the side chains of chain polymers ▲ Numerical formulas, chemical formulas, tables, etc. A photoconductive toner comprising a polymer component having an aryl group, a hydrogen atom, or a hydroxyl group. (2) 1 charge transport material per 100 parts by weight of fixing resin
The photoconductive toner according to claim 1, characterized in that 0 to 50 parts by weight are used.