JPH1073962A - Irradiation-hardened toner grain - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to produce a toner picture image high in durability against an outside physical influence. SOLUTION: Toner grains characterized to include irradiation hardened toner resin and resin having a Tg of toner resin >=35 deg.C are provided. The resin is favourably UV-resin to be hardened and a member to be selected from a group consisting of an unsaturated polyester/polyurethane acrylate mixture and an unsaturated polyester/polyurethane-vinylether mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION This invention relates to radiation curable
able) compound. The invention also relates to a method for producing a toner image in which the toner image is highly resistant to abrasion.

[0002]

BACKGROUND OF THE INVENTION For example, electro (photo) graphy,
In the case of image forming methods such as magnetography and ionography, a latent image is formed, which is developed by attracting so-called toner particles. The later developed latent image (toner image) is transferred onto the final substrate and fused to this substrate. In the case of DEP, so-called toner particles are deposited image-wise directly on the final substrate and fused to this substrate.

[0003] Toner particles are basically polymer particles containing a polymer resin as a main component and various components mixed with the toner resin. Apart from the colorless toner used, for example, for finishing functions, the toner resin contains at least one black and / or coloring substance, for example a coloring pigment.

[0004] In the various imaging methods described above, the toner particles can be present in a liquid or dry developer composition.

In most cases, it is preferred to use a dry developer composition. The main advantage of using a dry developer composition is that there is no need to remove the liquid phase after development.
The absence of evacuation of (mainly organic) liquids is desirable from both economic and ecological perspectives.

[0006] However, in all methods using dry particulate material to form an image, the image is deposited on a substrate by applying the particulate marking elements as multiple superimposed layers. The problems with the multiply superposed layers of marking particles, which are fixed in some way on the substrate, vary not only with regard to the quality of the image, but also with respect to the stability of the image and the mechanical issues.

For example, EP-A 471 894, EP-
A 554 981, US 4,828,950 and U
S 4,885,603 disclosed the application of a layer of transparent toner particles over the toner image to provide better resistance to physical damage.

For example, in US Pat. No. 3,723,114, the problem of storability of a fused toner image has been proposed, and the main problem is that the toner image becomes sticky after storage depending on storage conditions. The problem has been solved by using a substantial proportion of the thermosetting polymer in the toner resin.

The use of photo-curable toners is described, for example, in U.S. Pat.
S 5,470,683, giving a toner image with better weatherability. That application provides a capsule toner having a core containing a polymerizable compound, a polymerization initiator and other conventional toner components. The wick is surrounded by a hard shell, which is broken during the settling phase. After the fixing step, the polymerizable compound is polymerized by low energy visible light in this particular disclosure. Although the description of these disclosures produces a toner layer that is not easily damaged, the nature of the solution itself limits the variety of resins that can be used to make the toner. Accordingly, further improvements along the lines of the disclosure cited above are desirable.

[0010]

OBJECTS AND SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a toner image which is very resistant to external physical influences.

It is a further object of the present invention to provide a method for forming a toner image that is very resistant to the effects of common organic solvents.

It is a further object of the present invention to provide a method for producing a toner image that is very weather resistant.

Still another object of the present invention is to provide a method for producing a toner image which is very resistant to external physical influences and exhibits uniform gloss.

Further objects and advantages of the present invention will become clear from the detailed description hereinafter.

The object of the present invention is realized by the provision of toner particles comprising a radiation-curable compound, wherein the radiation-curable compound has a Tg of ≧ 35 ° C.

[0016]

DETAILED DESCRIPTION OF THE INVENTION Toner particles used in electrostatographic printing equipment have very high mechanical strength because they can withstand mechanical effects (pressure, friction, etc.) in the printing equipment before and during development. Therefore, it is important to preserve the mechanical strength of the toner particles.

Accordingly, the radiation curable compound to be inserted into the toner particles according to the present invention preferably includes not only a monomer compound but also an oligomer or polymer compound. As long as the mixture of the radiation-curable compounds (ie the radiation-curable composition) itself has a Tg of ≧ 35 ° C.,
The monomer compound can be present in a mixture of the radiation curable compounds. The oligomeric or polymeric radiation curable compound has a Tg of ≧ 35 ° C., where the Tg is 40
Preferably it is higher than ° C.

The radiation curable composition or compound can be added to the toner particles in addition to the toner resin and other toner components. Due to the oligomeric or polymeric nature of the radiation curable compounds, these compounds can also be used as the sole toner resin. Although the toner particles of the present invention can be colored (i.e., contain pigments or dyes), the toner particles of the present invention are particularly useful where the purpose is to form a clear finish on a toner image.
When the transparent toner particles of the present invention are used to provide a transparent finishing layer on an image, an image having a very uniform gloss is obtained. The term "clear" as used herein means not providing a visible diffuse density in the wavelength range from 400 to 700 nm, which is integrated over that wavelength range. Defined as less than 15% light reduction. In the context of the present invention, an "image on a substrate" is a substrate with human-readable or / or machine-readable text, a substrate with figures, a substrate with pictures (both color and monochrome), And a substrate having a combination of at least two of the above.

Although the clear finish layer can be useful on any toner image, it was constructed by overlaying several layers of toner particles showing various thicknesses in the image, as well as various types of toner particles. Most toner images (eg, full-color toner images or black-and-white (monochrome) with a wide tonal range as disclosed in European Application 95202768 filed October 13, 1995)
It is particularly useful when applied over (in images). Such images have a relief structure. The clear finish layer can be made by depositing the transparent toner particles by an image-wise deposition stage, a non-image-wise deposition stage or a reverse-image-like deposition stage. The transparent toner particles are preferably deposited non-image-wise (i.e., as a uniform layer over the surface of the substrate with or without toner particles) or reverse-image-wise. Reverse-image-street means that there is a thicker fixed clear finish in the thinner areas of the image and a thinner fixed clear finish in the thicker areas of the image.

If the image contains both text and, for example, full color photographs, according to the invention the transparent toner particles containing the radiation curable compound are deposited only on the surface of the full color photographs and not on the text parts. Can be beneficial. In such a way, glossy photos are combined with low gloss text.

In the present invention, an electron beam-curable compound can be used.
It is preferably curable by light.

Radiation curable polymer compounds which are very useful in toner particles for use in the present invention are EP-
A UV-curable solid epoxy resin with a Tg of ≧ 35 ° C. as disclosed in A 667 381.
In this application, the solid composition (I) comprises (a) a solid having a Tg higher than 35 ° C., an oligomeric cationically polymerizable polyglycidyl ether or ester (II), or (II) in liquid or crystalline form. A mixture of a monomeric mono-, di- or poly-epoxy resin, or a mixture of (II) and a cyclic acetal; (b) a polyfunctional nucleophilic chain transfer agent;
It is stated to contain 3% by weight of a photoinitiator for the cationic polymerization (in terms of the amount of a), and (d) any customary additives for the coating powder. These compositions (I) are melted together and the cooled mixture is ground. Exemplary compositions have a Tg from 65 ° C to 115 ° C or more.

Other useful UV-curable resins for incorporation into the toner particles of the present invention are powders based on unsaturated polyesters and polyurethane acrylates, typical of such polymeric UV-curable systems. Is Hoec
ht High Chem, Hoechts-Sara
Available through Pero (Mi) Italy. One such system is ALFTALAT VAN 174.
No. 3 including a solid unsaturated polyester resin having a Tg of ≧ 52 ° C., and ADDITOL 03546 a urethane adduct having an acrylic functional group having a Tg of ≧ 47 ° C. The nature of this system is European
Coating Journal n ^o 9/95 60
6-608 (1995). Also useful in the present invention are powders comprising a mixture of a non-acrylate binder system, for example, an unsaturated polyester resin intercalated with maleic or fumaric acid and a polyurethane containing vinyl ether. Such a binder system is available from
and DSM resin, whose properties are Eu
ropean Coating Journaln ^o
3/96 115-117 (1996).

In order to carry out UV curing, it is necessary that a photoinitiator be present. Very useful initiators are sulfonium salts such as triarylsulfonium salts, triarylsulfonium hexafluorophosphate, benzophenone and the like. In the context of the present invention, very useful typical photoinitiators are, for example, 2-hydroxy-2-methyl-1-
Phenyl-propan-1-one, compound I, a mixture of compound I and compound II and compound III:

[0025]

Embedded image

The initiator (photoinitiator) is preferably inserted into the toner particles together with the UV-curable system. However, within the scope of the present invention, it is possible to have radiation-curable compounds and initiator pairs in various combinations: i) UV-curable compounds (or mixtures of UV-curable compounds) and Photoinitiator (or mixture of photoinitiators)
Ii) both the UV-curable compound (or mixture of UV-curable compounds) and the photoinitiator (or mixture of photoinitiators) Inserting the UV-curable compound (or mixture of UV-curable compounds) into the substrate, iii) inserting the UV-curable compound (or mixture of UV-curable compounds) into the toner particles UV-curable compound (or a mixture of UV-curable compounds)
And both a photoinitiator (or a mixture of photoinitiators) are inserted into the substrate; iv) a UV-curable compound (or a mixture of UV-curable compounds) is inserted into the toner particles and the photoinitiator ( Or a mixture of photoinitiators) into the substrate.

If a photoinitiator and / or UV curable compound is inserted into the substrate, the substrate preferably comprises a toner receiving layer.

The toner particles of the present invention are preferably UV-
A radiation-curable resin (radiation-curable compound or composition) that is a curable resin can be included as a single toner resin, or a radiation-curable resin can be mixed with another toner resin. In that case, all toner resins known in the art are useful for producing the toner particles of the present invention. The resin mixed with the radiation-curable resin can be a polycondensate (eg, polyesters, polyamides, co (polyester / polyamide), etc.), an epoxy resin, an addition polymer, or a mixture thereof.

The toner particles contain not only a compound having a radiation-curable group, but also an epoxy group, an aldehyde group, a hydroxyl group, a carboxyl group, a mercapto group,
It may be beneficial to include a reactive group RGA that is a member selected from the group consisting of an amino group and an amide group. In this case, the toner particles can include, for example, a toner resin or epoxy resin selected from the group described in Table 1 and a UV-curable solid resin (composition) having a Tg of ≧ 35 ° C.

[0030]

[Table 1]

* AV: Acid value in mgKOH / g resin ** HV: Hydroxyl value in mgKOH / g resin ⁺ Mn: Number average molecular weight (x1000) † Mw: Weight average molecular weight (x1000) DIANOL 22 is bis-ethoxylated Net for 2,2-bis (4-hydroxyphenyl) propane
Herlands AKZO CHEMIE.

DIANOL 33 is the AKZO CHEM of Etherlands for bis-propoxylated 2,2-bis (4-hydroxyphenyl) propane.
This is the IE product name.

In this embodiment of the invention where the toner particles further comprise a reactive group RGA, epoxy groups, aldehyde groups, hydroxyl groups, carboxyl groups, mercapto groups,
It is preferable to use a substrate containing a reactive group RGB which is a member selected from the group consisting of an amino group and an amide group, and is selected to form a reactive pair with the reactive group RGA. This embodiment has the advantage that the resin contained in the fixed image is not only radiation curable, but can also be thermally crosslinked and chemically linked to the substrate by a chemical bond.

In the embodiment in which the substrate has a reactive group RGB and the toner particles not only contain a radiation-curable compound having a Tg of ≧ 35 ° C. but also a reactive group RGA, either the toner particles or the substrate may be used. , Or both, with a catalyst to promote the reaction between the reactive groups RGA and RGB. These catalysts are, for example, acids (both organic and inorganic) and tertiary amines. Very suitable catalysts are p-toluenesulfonic acid, trimethylamine and triethylamine.

The toner particles of the present invention can be manufactured by any method known in the art. The toner particles contain toner components (for example, toner resin,
(A charge control agent, a pigment, etc.) and the radiation-curable compound. After melt-kneading, the mixture is cooled, the solidified mass is comminuted and ground, and the resulting particles are fractionated. "Emulsion polymerization" and "polymer emulsion" methods for toner production can also be used to produce the toner particles of the present invention. In the case of the "emulsion polymerization" method,
Water-immiscible polymerizable liquids are sheared to form droplets that are emulsified into an aqueous solution, and the polymerization of the monomer droplets occurs in the presence of an emulsifier; such methods are described, for example, in US Pat.
932,629, USP 4,148,741, US
P 4,314,932 and EP-A 255 71
No. 6. In the case of the "polymer emulsion" method, the pre-formed polymer is dissolved in a suitable organic solvent that is immiscible with water, the resulting solution is dispersed in an aqueous medium containing a stabilizer, and the organic solvent is evaporated. Drying the resulting particles; such methods are described, for example, in US Pat.
060.

The toner particles useful in the present invention have a particle size of 1 to 50 μm.
m, preferably 3 to 20 μm. When the toner particles are intended to be used for color image formation, the volume average diameter is preferably 3 to 10 μm, and most preferably 3 to 8 μm. The particle size distribution of the toner particles can be of any type. However, essentially (some positive or negative distortion is allowed, but less positive distortion with less particles less than the undistorted distribution is preferred), by number or volume, less than 0.5, more preferably 0.3 Preferably, it has a Gaussian or normal particle size distribution with a coefficient of variation (standard deviation divided by the average) (v).

The toner particles useful in the present invention can include any conventional toner component, such as charge control agents, both pigmented and black pigments, inorganic fillers, anti-slip agents, waxes, and the like. Other additives useful in charge control agents, pigments and toner particles to be used in the toner compositions of the present invention can be found, for example, in EP-A 601 235.

The toner particles can be used as single-component developers, both magnetic and non-magnetic single-component developers. The toner particles can be used in a multi-component developer where both magnetic carrier particles and toner particles are present. Toner particles can be negatively charged and can be positively charged.

The present invention includes: i) image-wise depositing toner particles comprising a radiation curable resin having a Tg of ≧ 35 ° C. on a substrate; ii) melting said toner particles on said substrate; iii. A) a method of forming a toner image on a substrate, including the step of radiation curing the fused toner particles.

The invention further comprises: i) depositing the toner particles image-wise on a substrate; ii) depositing the transparent toner particles comprising a radiation-curable resin having a Tg of ≧ 35 ° C. Iii) fusing the toner particles on the substrate, and iii) radiatively curing the fused toner particles, the method comprising forming a toner image on the substrate. .

Radiation curing can be performed on-line, for example at the melting station of the electrostatographic apparatus itself, or at a station immediately adjacent to the melting station.

Radiation curing can also be performed off-line in another device, where the molten layer of toner particles is heated again,
Irradiated with curing light. It is important that radiation (UV-) curing be performed on the molten toner particles and while the toner receiving layer has some fluidity. The radiation curing is preferably carried out at a temperature of at most 150 ^° , most preferably at most 120 ^° . Therefore 120
50 to 2000 Pas at 100C, preferably 100 to 2000 Pas
It is preferred to use toner particles containing a radiation curable compound having a Tg of ≧ 35 ° C. having a melt viscosity of 1000 Pas. All melt viscosities referred to herein are measured by RHEOMETRICS dynamic rheometer, RVEM-
200 (One Possumtown Road, P
iscataway, NJ 08854 USA). The viscosity measurement is performed at a sample temperature of 120 ° C. A sample weighing 0.75 g is weighed with a measuring gap (about 1.5 mm) between two parallel plates of 20 mm diameter, one of which oscillates around its vertical axis at 100 rad / s and an amplitude of 10 ^-3 radians. ). The fluidity of the toner receiving layer at the above temperature is determined by waxes, or “thermal solvent” or “thermosolvent”.
Can be improved by inserting a "heat solvent", also called a "heat solvent", into the toner receiving layer on the substrate.

The term "heat solvent" in the present invention is a solid state at a temperature lower than 50 ° C., but when heated above that temperature, it becomes a plasticizer for the binder of the layer into which it is inserted. Organic materials that cannot be hydrolyzed. Useful for that purpose is US-P 3,3
Polyethylene glycol having an average molecular weight in the range of 1,500 to 20,000 described in 47,675. Further, compounds such as urea, methylsulfonamide and ethylene carbonate described in U.S. Pat. No. 3,667,959 can be mentioned as a heat solvent, and tetrahydro-thiophene-1,1-dioxide,
Compounds such as methyl anisate and 1,10-decanediol are used in Research Disclosure, De.
member 1976, (item 15027) pa
ges 26-28, described as a heat solvent. Another example of heat solvent is US
-P3,438,776 and 4,740,446 and in published EP-A 0 119 615 and 0 12
2 512, as well as DE-A 3 339 810.

The toner receiving layer may further comprise a binder or a mixture of binders, as well as stabilizers, toning agents, antistatic agents, spacing particles (polymeric or inorganic). In addition to the components, the toner receiving layer may contain other additives such as free fatty acids, antistatic agents such as F ₃ C (CF ₂ ) ₆ C
Non containing fluorocarbon group as in the case of _{ONH (CH 2 CH 2 O)} -H - ionic antistatic agents, ultraviolet light absorbing compounds,
White light reflective and / or ultraviolet reflective pigments, and / or
Alternatively, an optical brightener can be contained.

The step of depositing the transparent toner particles can be an image-wise deposition step, a non-image-wise deposition step or a reverse-image-wise deposition step, as described above. For methods that include the step of depositing transparent toner particles on an image in addition to the step of image-wise depositing the toner particles on a substrate, all of the toner particles can comprise a radiation curable resin. However, it is sufficient within the scope of the present invention that only the transparent toner particles comprise a radiation-curable resin having a Tg of ≧ 35 ° C.

The present invention includes: i) means for image-wise depositing toner particles comprising a radiation curable resin having a Tg of ≧ 35 ° C. on a substrate; ii) fusing the toner particles on the substrate And an apparatus for forming a toner image on a substrate, characterized in that the apparatus further comprises means for on-line radiation curing of the fused toner particles.

The present invention further provides: i) means for image-wise depositing toner particles on a substrate; ii) transparent toner particles comprising a radiation-curable resin having a Tg of ≧ 35 ° C .; Iii) means for fusing the toner particles on the substrate, and means for on-line radiation curing of the fused toner particles. And an apparatus for forming a toner image on the substrate.

The means for fusing the toner particles to the substrate can be any means known in the art, and the means for fusing the toner particles of the present invention may be contact (eg, Heat-pressure rollers) or non-contact means. However, in the case of the device according to the invention, it is preferred that the melting means is mainly, preferably exclusively, non-contact means. The non-contact fusing means of the present invention includes, for example: (1) an oven heating method in which heat is applied to the toner image by hot air covering a wide portion of the support sheet, and (2) an infrared light in which heat is absorbed in the toner. And / or may be provided by visible light, and may include various embodiments such as radiant heating, where the light source is, for example, an infrared lamp or a flash lamp. According to a particular embodiment of "non-contact" fusing, heat is transferred through the substrate to the non-fixed toner by contacting the support with a heating element, such as a hot metal roller, on the side remote from the toner image. Reach the picture. In the case of the present invention, radiant heating, for example, non-contact melting by infrared rays (IR rays) is preferred.

In the case of the apparatus according to the invention, it is preferred to use toner particles containing a UV-curable resin, so that the means for radiation-curing the toner particles is a means for UV-curing (for example a UV lamp or the like). UV-light emitters). For the device of the present invention, radiation curing preferably proceeds on-line. Thus, the means for fusing the toner image emits infrared light (which is an infrared radiator) and
The means for curing (e.g. one or more UV-emitting lamps, e.g. high-pressure mercury lamps) is installed immediately after the fusing means, and the UV
Preferably, curing proceeds. Infrared radiator (means for melting toner particles) and UV emission lamp (means for radiation curing) in one station (fixing / curing station) so that melting and radiation curing proceed simultaneously Are also desirable design features of the device of the present invention. The apparatus of the present invention can include more than one fusing / curing station if so desired. UV emission means is 20W / cm-150W
It is preferably a UV radiator having a capacity (intensity) of / cm.

In the case of the apparatus of the present invention, the toner particles are
The means for deposition in a direct manner are direct electrostatic printing means (D
EP), where the charged toner particles are attracted to the substrate by an electric field, and the toner flow is modulated by a printhead structure that includes a printing opening and a control electrode.

The means for image-wise depositing toner particles can be a toner deposition means on which a latent image is initially formed. Within such a device, within the scope of the present invention, the means for image-wise depositing toner particles include: means for producing a latent image on the latent image bearing component; Means for developing the latent image by deposition to form a developed image; and means for transferring the developed image onto the substrate.

The latent image can be a magnetic latent image developed by magnetic toner particles (magnetography) or, preferably, an electrostatic latent image. Such an electrostatic latent image is preferably an electrophotographic latent image, and the means for producing the latent image in the present invention is a light emitting means, such as a light emitting diode or a laser, wherein the latent image bearing component is a photoconductor. It is preferred to include

[0053]

【Example】

1. Preparation of Toner Particles and Developer Yellow toner (Y) 49 parts polyester having an acid value AV of 17 mg KOH / g (No. 2 in Table 1) and 49 parts polyester having an AV of 18 mg KOH / g (No. 3 in Table 1) ) To two parts of S
It was melt-blended with ICOECHTGELB D 1355 DD (color index PY13, trade name of BASF AG, Germany) at 110 ° C for 30 minutes in a laboratory kneader.

After cooling, the solidified mass was pulverized and
NE Fliessbettgegenstrahlm
Uhle 100AFG type (trade name), milled using ALPINE multi-plex jig-
It was further separated using a Zag sorter 100MZR (trade name). The average particle size of the separated toner
It was measured with a r Counter model Multisizer (trade name) and found to be 8.0 μm by volume.

In order to improve the fluidity of the toner mass, 0.5% of hydrophobic colloidal silica particles (BE)
(T-value 130 m ² / g).

Magenta Toner (M) The production of the yellow toner was repeated.
ECHTGELB 2 parts PERM instead of PY13
ANENT CARMIN FFB 02 (color index PR146, Hoechst AG, Germany
Trade name).

Cyan Toner (C) The production of the yellow toner was repeated.
ECHTGELB 2 parts HELI instead of PY13
OGEN BLAU D7070DD (color index P
B15: 3, trade name of BASF AG, Germany) was used.

Black toner (K) The production of the yellow toner was repeated.
2 parts CABO instead of ECHTGELB PY13
T REGAL 400 (carbon black, Cabo
t Corp. High Street 125, Bo
ston, U.S.A. S. A. Trade name).

The four toners, Y, M, C and K, are 120
At 250 ° C. (16 Hz
As measured above at a frequency of).

Transparent toner (CT) Hoechst High Chem, Hoechts
-ALF from Sara, Pero (Mi) Italy
Available under the trade name TALAT VAN 1743 ≧
68 parts of a solid unsaturated polyester resin having a Tg of 45 ° C., Horchst High Chem, Hoec
hts-Sara, Pero (Mi) Italy to A
29 parts of an aliphatic urethane adduct having an acrylic functionality having a Tg of ≧ 52 ° C. available under the trade name DDITOL 03546, and Ciba-Geigy, Bas
el, SWITZERLAND to IRGACURE6
3 copies available under 51 trade names

[0061]

Embedded image

At 110 ° C. in a laboratory kneader.
Melted for minutes.

After cooling, the solidified mass is pulverized and
NE Fliessbettgegenstrahlm
Uhle 100AFG model (trade name), and milled using ALPINE composite jig-sag sorting machine 100MZ
It was further separated using an R type (trade name). The average particle size of the separated toner was measured with a Coulter Counter model Multisizer (trade name) and found to be 8.0 μm by volume. The transparent toner CT had a melt viscosity of 195 Pas at 120 ° C.

In order to improve the flowability of the toner mass, the toner particles are made up of 0.3% hydrophobic colloidal silica particles (BE).
(T-value 130 m ² / g).

Developing agent Using each of the toners prepared above, the mixture of toner particles and colloidal silica was added at a ratio of 4% to 55 μm.
Silicon-coated Cu-Z having an average diameter of m
A carrier-toner developer was formed by mixing with the n-ferrite carrier particles.

2. Printing Examples Commercially available CHROMAPRESS (Agfa-Gevae
rt NV, Mortsel, and Belgium) to form a full-color toner image. The image was covered with a layer of clear toner such that 0.9 mg / cm ² of clear toner was present.

Melting is performed by radiant heating (IR-
Immediately after cooling the molten toner layer without cooling, using a high-pressure mercury lamp and irradiating with a UV-lamp at an intensity of 80 W / cm for 0.5 seconds.

A second image without UV-curing was also made.

The resistance of both images to the solvent was tested by rubbing the images 10 times with a cloth soaked in MEK (methyl ethyl ketone). The UV-cured image [missing], but the non-cured image disappeared after one rub.

The UV-cured image was obtained using a gloss measuring device (MINOLTA MULTI-GROSS 268,
When measured under an angle of 60 ^° using Minolta, Osaka, Japan, it showed a uniform high gloss of 90% or more.

Continued on the front page (72) Inventor Sergiu Tavernier Belgium B 2640 Malt Cell Septes Trat 27 Agfa-Gevuert Na Mrose Fennoutjaps (72) Inventor Danny Van Unsel Belgium B 2640 Malt Cell Septes Trat 27, Agfa-Gevert Naar, in Mrose-Fennoutjap

Claims (4)

[Claims] 1. A toner resin, wherein the toner further comprises a radiation curable compound having a Tg of ≧ 35 ° C., the radiation curable compound is a UV-curable resin, and the toner particles Toner particles further comprising a photoinitiator. 2.) i) depositing image-wise toner particles comprising a radiation-curable resin having a Tg of ≧ 35 ° C. on a substrate; ii) fusing the toner particles on the substrate; A method of forming a toner image on a substrate comprising radiation curing the fused toner particles. 3.) i) depositing the toner particles image-wise on a substrate, and ii) applying the transparent toner particles comprising a radiation-curable resin having a Tg of ≧ 35 ° C. to the image-deposited toner. Depositing on the particles, iii) fusing the toner particles on the substrate, and iii) radiatively curing the melted toner particles. 4. means for image-wise depositing toner particles comprising a radiation-curable resin having a Tg of ≧ 35 ° C. on a substrate, and means for fusing said toner particles on said substrate. An apparatus for forming a toner image on a substrate comprising means for on-line radiation curing of the fused toner particles, wherein the means for melting the toner particles comprises an infrared radiator. An apparatus, wherein the means for curing the fused toner particles comprises a UV-light emitter.