JP2003122057A - Display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display on which an image section and a background section are to be formed by an electrophotographic system, and which decreases the pinholes in the image section and the background section and does not disturb the images at a high temperature of about 100 deg.C. SOLUTION: This display obtained by respectively forming the image section and the background section with a color toner and a black toner by an electrophotographic system on an image recording medium, is characterized in that the color toner and the black toner respectively satisfy a number average molecular weights of 1,000 to 6,000 and a mass average molecular weights of 30,000 to 150,000 by gel permeation chromatography in solution of tetrahydrofuran (THF) and have peaks in the molecular weight distributions respectively of the region of the molecular weight 1,000 to 10,000 and the region of the molecular weight 100,000 to 1,500,000 and the ratio occupied by the pinholes per unit area is <=1×10<-3> % in the image sections and the background section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display body on which an image is formed (recorded) by an electrophotographic method. Further, the present invention particularly relates to a display body which is characterized in that only the image portion is allowed to transmit light for display by backlight illumination. In the present invention, the image area means an image area formed by color toner, and the background area means an image area formed by black toner.

[0002]

2. Description of the Related Art In recent years, it has become widespread to form a color toner image on a transparent film by an electrophotographic method, provide a transparent film having the toner image to an OHP and use it as a projection image. By developing this technology, a panel of a type that forms an image portion and a background portion with a color toner or black toner on a transparent film and displays only the image portion through backlight illumination, that is, The use as a backlight type display has been considered.

In the case of such a backlight type display body,
The image part is required to have some transparency, and the background part is required to be concealed. The transparency in the image area is achieved by keeping the colorant concentration in the toner within an appropriate range, as in the case of the conventional OHP image area. On the other hand, with respect to the hiding property of the background portion, an extremely high hiding property with a transmission density of 3 or more may be required depending on the type of display body. Therefore, in order to improve the hiding property, that is, as a method of increasing the transmission density of the background portion formed of black toner, adjustment has been made by increasing the content of carbon black which is a black colorant. The transmission density here is the common logarithm of the reciprocal of the transmittance (T) when irradiated with visible light (log (1 / (
T)).

[0004]

However, even if most of the area of the image portion or the background portion satisfies the preferable transmission density, there is a pinhole in which the toner is not fixed, and the light is emitted from the pinhole. The leakage may result in a defective display body. More specifically, in the current electrophotographic system, the electrophotographic toner is usually heated and melted at 140 ° C. to 170 ° C. to be fixed on the image recording medium, so that the toner is contained in the toner layer during fixing. It has been clarified that air escapes and pinholes having a circle equivalent diameter of about 0.2 mm or less are generated in the toner image after fixing. In a normal print image,
The existence of pinholes does not pose any problem in terms of image quality, but it is a fatal defect in a backlight type display body, and therefore a technique for reducing pinholes is required.

[0005] In addition, home appliances, automobiles, building materials, outdoor POPs, etc. can be considered as fields to which the display is applied. In these usage environments, light resistance, heat resistance, water resistance, and cold / heat resistance cycle are generally used. It is required to have resistance corresponding to each use condition such as resistance, acid resistance and alkali resistance. For example, in the case of a vehicle-mounted meter panel, 90-
A durability of about 1000 hours is required in the range of 100 ° C. The term "durability" as used herein means that no defects are observed with respect to cracking, deformation, discoloration, and the like. In the Assy body test, the vehicle-mounted meter panel is sandwiched between the case plate and the decorative plate while being in contact with each other, and heat and stress simultaneously act as a load, which is a severe test.

However, the toner for electrophotography is usually 140 to
Since the binder resin contained in the toner for electrophotography is designed so that it is heated and melted in the range of 170 ° C. and fixed on a paper or the like, the toner may be removed when stress acts at high temperature. There is a concern that the image may flow and the image may be disturbed. As a means for making the toner hard to flow at high temperature, that is, for increasing the viscosity of the toner, increasing the molecular weight of the binder resin may be considered, but if it is too high, the pulverizability deteriorates during the production of the toner. Therefore, there is a problem that the productivity is lowered.

Therefore, the present invention has been made to solve the above problems, and more specifically, in a display body in which an image portion and a background portion are formed by an electrophotographic method, the image portion and the background portion Reduces pinholes and further 100 ℃
An object of the present invention is to provide a display body in which an image is not disturbed even at a high temperature.

[0008]

The above object can be achieved by the present invention described below. That is, the present invention is

<1> A display member in which an image portion and a background portion are formed by a color toner and a black toner on an image recording medium by an electrophotographic method, wherein the color toner and the black toner are respectively , By gel permeation chromatography in THF solubles,
Satisfying that the number average molecular weight is 1000 to 6000 and the weight average molecular weight is 30,000 to 150,000, and
Molecular weight range of 1,000 to 10,000 and molecular weight of 10,000
0 to 1500000 regions each have a peak in the molecular weight distribution, and in the image portion and the background portion,
The ratio of pinholes per unit area is 1 × 10 ^-3 %
It is a display body characterized by the following.

<2> After fixing both images of the image portion and the background portion by the color toner and the black toner on the image recording medium, the melt viscosity of both toners is 1 × 10 ⁷ to
The display body according to <1>, which is heat-treated at a temperature in the range of 1 × 10 ³ Pa · s.

<3><1> or <wherein the image recording medium is a transparent plastic film
2> is a display body.

<4> Both the color toner and the black toner have at least a binder resin, and the binder resin is a polyester resin, a polystyrene resin, a styrene-acrylic resin, an epoxy resin, a silicone resin, a polyurethane resin, The display body according to any one of <1> to <3>, which is at least one resin selected from a polyamide resin and a polyolefin resin.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. The display body of the present invention is formed by forming an image portion and a background portion on the image recording medium by an electrophotographic method using color toner and black toner, respectively. Hereinafter, the color toner and the black toner will be appropriately referred to as electrophotographic toners or simply toners.

<Electrophotographic Toner> The electrophotographic toner used in the present invention is prepared by using the tetrahydrofuran (hereinafter,
The number average molecular weight of the soluble component (referred to as “THF”) measured by gel permeation chromatography is 1,000 to
6000, weight average molecular weight 30,000 to 150,000
And the molecular weight is 1000 to 1000
It is necessary to have a peak in the molecular weight distribution in each of the 0 region and the molecular weight range of 100,000 to 15,000,000. Here, the “number average molecular weight”, the “weight average molecular weight”, and the “peak in the molecular weight distribution” by gel permeation chromatography in the THF soluble content of the electrophotographic toner used in the present invention are respectively “ "Specific number average molecular weight", "specific weight average molecular weight", and "specific molecular weight peak".

As described above, the specific number average molecular weight of the electrophotographic toner used in the present invention is 1000 to 6000, and more preferably 1500 to 5000.
The toner for electrophotography used in the present invention has a specific weight average molecular weight of 30,000 to 150,000,
It is more preferably 000 to 130,000. When the specific number average molecular weight is less than 1000 and / or the specific weight average molecular weight is less than 30,000, (1) the mechanical strength of the toner itself becomes weak, and the toner becomes fine particles when agitated during development, causing fog and the like. (2) The strength of the fixed image is weak, and the toner is likely to fall off when the image is bent. (3) The viscosity of the toner at 100 ° C. is as low as 1 × 10 ⁵ Pa · s or less. Therefore, there is a problem in that heat resistance is a concern.
In particular, the problem of heat resistance in (3) above is that when the display body of the present invention is used in a vehicle-mounted meter panel, the viscosity at 100 ° C. is low because it comes into contact with a case plate or a decorative plate when the Assy body is attached, There was further concern that the toner would flow and the image would be disturbed. In addition, the specific number average molecular weight is 6000
Larger and / or specific weight average molecular weight of 150
If it is greater than 000, the pulverizability during toner production deteriorates.

As described above, the specific molecular weight peak of the electrophotographic toner used in the present invention has a molecular weight of 1,000 to 1.
00000 region and molecular weight 100,000 to 15,000,000
And preferably has a molecular weight of 20.
Region of 00-8000 and molecular weight 200,000-1400
Present in each of the 000 areas. The specific molecular weight peak indicates the maximum value in the molecular weight distribution curve.
By containing the specific molecular weight peak in the upper two regions, particularly excellent performances are exhibited in various properties such as fixability (property whether fixable temperature is high or low), heat resistance, and pulverizability. Further, the low molecular weight component of the electrophotographic toner used in the present invention refers to one having a molecular weight of 50,000 or less in the THF soluble component, and the ratio of the low molecular weight component is 50 with respect to the total amount of the THF soluble component. ~ 95% by weight
Is preferable, and more preferably 60 to 95% by weight.

The electrophotographic toner used in the present invention is
A gel component insoluble in THF may be included. The amount of the gel component is preferably 20% by weight or less, and more preferably 15% by weight or less based on the total amount of the electrophotographic toner. When the amount of the gel component is 20% by weight or more, the dispersibility of the gel is deteriorated, and as a result, a toner containing no colorant is generated or the pulverizability is deteriorated.

The electrophotographic toner used in the present invention is
It is composed mainly of a binder resin and a colorant. Examples of the binder resin used in the toner include styrenes such as styrene and chlorostyrene; monoolefins such as ethylene, propylene, butylene and isoprene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl acetate; acrylic. Α-methylene aliphatic monocarboxylic acid esters such as methyl acidate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate; Examples include vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether; homopolymers or copolymers of vinyl ketone such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone. As a typical binder resin, polystyrene, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-anhydrous can be used. Maleic acid copolymer, polyethylene, polypropylene can be mentioned.

Further, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin and waxes can be mentioned. Among these, polyester is particularly suitable as the binder resin. The polyester resin used in the present invention is synthesized from a polyol component and an acid component by polycondensation.
Examples of the polyol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4
-Butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol, bisphenol A / ethylene oxide adduct, bisphenol A
-Propylene oxide adduct and the like can be mentioned. Examples of the acid component include maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, dodecenylsuccinic acid, trimellitic acid, pyromellitic acid, cyclohexanetricarboxylic acid, 1,5-cyclohexanedicarboxylic acid, and 2,5. , 7-naphthalene tricarboxylic acid, 1, 2,
4-naphthalene tricarboxylic acid, 1,2,5-hexane tricarboxylic acid, 1,3-dicarboxyl-2-methylene carboxypropane tetramethylene carboxylic acid and their anhydrides can be mentioned. Further, a blend of a plurality of resins may be used.

As the colorant, black is carbon black, and magenta is C.I. I. Pigment Red 48:
1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 57: 1 and C.I. I. Pigment Yellow 97, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 180, and Cyan for Cyan. I. Pigment Blue 15: 1, C.I. I. Pigment Blue 15: 3 and the like can be given as representative examples, but the present invention is not limited to these.

Further, in the backlight type display body of the present invention, white is often used in the image portion. Examples of the white colorant include titanium oxide, silica, tin oxide, aluminum oxide, magnesium oxide and the like, but titanium oxide is preferable from the viewpoint of light resistance. As titanium oxide,
The rutile type, the anatase type, and the brookite type are well known, but the rutile type is preferable from the viewpoint of hiding property. Further, those whose surface is treated with alumina or silica for the purpose of improving light resistance are preferable.

Magenta, yellow used in the image section,
In the case of cyan and white toners, since they are displayed by backlight illumination, transparency is required to some extent, and the transmission density is preferably 0.1 to 1, and 0.3 to 0.
More preferably, it is 7. Therefore, the content of the colorant in the toner is usually 4 to 40% by weight, preferably 6 to 3%.
It is 5% by weight. Further, the toner weight TMA per unit area on the image recording medium is preferably 0.3 to 1 mg / cm ² .

On the other hand, in the case of the black toner used in the background portion, the concealing property is required, and the transmission density is preferably 3 or more. To increase the transmission density, increase the content of carbon black, which is a coloring agent, and increase the T of black toner.
It is possible to raise MA. However, since carbon black is electrically conductive, if it is added too much, the electrical resistance of the toner decreases, and as a result, the charge amount decreases and fogging and toner scattering occur. Further, BCO is generated because the developer resistance is also lowered. Also, T
If MA is too high, transfer failure to the image recording medium will occur,
Image unevenness occurs. Therefore, fogging, toner scattering, B
In order to satisfy the transmission density of 3 or more without causing CO and image unevenness, it is preferable that the content of carbon black is 4 to 15% by weight and the TMA of the black toner is 1 to ² mg / cm ^2. .

The electrophotographic toner used in the present invention may optionally contain known additives such as a charge control agent and wax. Examples of the charge control agent include azo metal complexes, metal complexes of salicylic acid or alkyl salicylic acid, and metal salts. As the wax, various waxes such as olefinic waxes such as low molecular weight polyethylene and low molecular weight polypropylene, plant waxes such as carnauba, other animal waxes and mineral waxes can be used.

The method for producing the electrophotographic toner used in the present invention is not particularly limited, but for example, the melt pulverization method is preferable. According to the melt pulverization method, a toner can be produced by mixing the above toner materials with a Banbury mixer, a kneader coater, a continuous mixer, an extruder, etc., melt-kneading, pulverizing, and classifying. The average particle diameter of the toner is 30 μm or less, preferably 4 to 20 μm.

The electrophotographic toner used in the present invention may further contain a fluidizing agent and the like. Examples of the fluidizing agent include silica, titanium oxide, aluminum oxide and the like.

The electrophotographic toner used in the present invention is
Used as a two-component developer by mixing with a suitable carrier. Any known carrier can be used. Specifically, ferrite, magnetite, iron powder,
There are also those whose surfaces are coated with a styrene resin, a fluorine resin, a silicone resin, an epoxy resin, or the like. It is also possible to add carbon black or a metal oxide-based conductive powder to the coating resin and use it as a semi-conductive or conductive carrier. The particle size of the carrier is generally set in the range of 20 to 100 μm.

The weight mixing ratio of the toner in the two-component type developer controls the charge amount of the toner and further determines the limit of the toner development amount, and is an important factor for determining TMA. It is set to 12% by weight. If it is less than 2% by weight, the charge amount is too high, or the upper limit of the toner development amount is small, so that it is difficult to obtain a desired TMA. On the other hand, if it is more than 12% by weight, the amount of charge is too low and fog and toner scattering are likely to occur.

<Image Recording Medium> As the image recording medium used in the present invention, a transparent plastic film is used. As the plastic film, polyethylene terephthalate film, polysulfone film, polyphenylene oxide film, polyimide film,
There are polycarbonate film, cellulose ester film, polyamide film and the like. Among them, a polyethylene terephthalate film is particularly preferable in terms of heat resistance and transparency. The thickness of the plastic film must be such that wrinkles do not occur when the film becomes soft due to heating during heat fixing, and that it can be cut and punched after image formation, generally 100 μm or more, Preferably, a thickness of 125 μm or more is required. The upper limit of the thickness of the plastic film is preferably 200 μm or less in consideration of a decrease in light transmittance.

The display of the present invention requires that the proportion of pinholes per unit area in the formed image portion and background portion is 1 × 10 ⁻³ % or less. for that reason,
The display according to the present invention has a melt viscosity of 1 × 10 ⁷ to 1 × 10 ³ Pa · toner with respect to a toner image (image portion and background portion) thermally fixed on an image recording medium by an electrophotographic method.
It is preferable to perform the heat treatment at a temperature in the range of s.

The melt viscosity of the toner is 1 × 10 ⁷ to 1 × 10 ^3.
In the range of Pa · s, the intermolecular cohesive force of the binder resin, which is the main component of the toner, is weak and viscous flow occurs relatively easily, so the toner flows appropriately (to the extent that the image is not disturbed). , The pinhole that existed before the process is filled. That is, by performing such heat treatment, pinholes can be reduced. The melt viscosity is 1 × 10 ⁷ Pa ·
If it is s or more, the flow is not sufficient, and if it is 1 × 10 ³ Pa · s or less, the toner image is easily disturbed. In such heat treatment, the heating time is about 10 minutes to 1 hour.

The melt viscosity of the electrophotographic toner is determined as follows. Shimadzu Corporation Flow Tester C
FT-500C type is used, and the die (nozzle) diameter is 0.
Extrusion load of 100 kg with a thickness of 5 mm and a thickness of 1.0 mm was applied, with an initial setting temperature of 70 ° C. and after a preheating time of 300 seconds, 5
The melt viscosity at each temperature when the temperature is raised at a constant rate of ° C / min is measured. Further, the evaluation of the ratio of the pinholes of the display body (pinhole ratio) is obtained as follows. Luzex FT, image processing analyzer manufactured by Nireco Corporation
The image is taken from a TV camera with a field of view of about 500 mm ² by using, and the total area of the pinholes is obtained. Then, the pinhole ratio is obtained by calculating the percentage of the total area of the pinholes with respect to the field-of-view area.

Thus, when the display body of the present invention is manufactured, the above heat treatment is performed so that the ratio of pinholes per unit area of the image portion and the background portion is 1 × 1.
It can be reduced to 0 ^-3 % or less, and can be suitably used as a backlight type display.

[0034]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

[0035] [Toner A for electrophotography] (Composition of toner A for electrophotography) ・ Polyester resin (A: terephthalic acid / b: fumaric acid / c: bisphenol A propylene oxide Deadduct / d: Polycondensation product of bisphenol A ethylene oxide adduct, Polycondensation molar ratio; a: b: c: d = 80: 20: 50: 50, number average molecular weight 300 0, weight average molecular weight 5000, molecular weight peak 5000) ... 60% by weight ・ Polyester resin (A: terephthalic acid / b: trimellitic anhydride / c: dodecenyl succinic acid / d: Bisphenol A propylene oxide adduct / e: Bisphenol A ethylene Polycondensation product of oxide adduct, polycondensation molar ratio; a: b: c: d: e = 85 : 10: 5: 50: 50, number average molecular weight 6000, weight average molecular weight 60000, Molecular weight peak 10000, gel component 35% by weight) ... 34% by weight ・ Carbon black (# 25B, Mitsubishi Chemical): 6% by weight

(Production Method of Toner A for Electrophotography) Each of the above
Pre-mix the ingredients thoroughly with a Henschel mixer and mix.
Melt and knead with a strander, cool and put in a jet mill.
Perform finer pulverization and then classify twice with a wind-powered classifier
A black toner A having a volume average particle size of 8.0 μm was obtained. This
100 parts by weight of black toner A particles and BE as an external additive
T specific surface area 100 m ²/ G of hydrophobic titanium oxide fine particles
Mix 0.6 parts by weight with a Henschel mixer and charge.
A toner A for child photography was prepared.

(Physical Properties of Toner A for Electrophotography) By dissolving the obtained toner A for electrophotography in a THF-soluble component and measuring by gel permeation chromatography,
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
Specific number average molecular weight is 2000, specific weight average molecular weight is 4
0000, specific molecular weight peaks are 2500 and 20000
It was 0. The ratio of the low molecular weight component in the electrophotographic toner A was 70% by weight, and the amount of the gel component insoluble in THF was 8% by weight. Furthermore, the melt viscosity at 100 ° C. was 2 × 10 ⁵ Pa · s, and the melt viscosity at 110 ° C. was 5 × 10 ⁴ Pa · s.

[0038] [Toner B for electrophotography] (Composition of toner B for electrophotography) ・ Polyester resin (A: terephthalic acid / b: fumaric acid / c: bisphenol A propylene oxide Deadduct / d: Polycondensation product of bisphenol A ethylene oxide adduct, Polycondensation molar ratio; a: b: c: d = 80: 20: 50: 50, number average molecular weight 300 0, weight average molecular weight 5000, molecular weight peak 5000) ... 10% by weight ・ Polyester resin (A: terephthalic acid / b: trimellitic anhydride / c: dodecenyl succinic acid / d: Bisphenol A propylene oxide adduct / e: Bisphenol A ethylene Polycondensation product of oxide adduct, polycondensation molar ratio; a: b: c: d: e = 85 : 10: 5: 50: 50, number average molecular weight 6000, weight average molecular weight 60000, Molecular weight peak 10000, gel component 35% by weight) ... 84% by weight ・ Carbon black (# 25B, Mitsubishi Chemical): 6% by weight

(Method for producing electrophotographic toner B) Each of the above
Pre-mix the ingredients thoroughly with a Henschel mixer and mix.
Melt and knead with a strander, cool and put in a jet mill.
Perform finer pulverization and then classify twice with a wind-powered classifier
A black toner B having a volume average particle diameter of 8.0 μm was obtained. This
100 parts by weight of black toner B particles and BE as an external additive
T specific surface area 100 m ²/ G of hydrophobic titanium oxide fine particles
Mix 0.6 parts by weight with a Henschel mixer and charge.
A toner B for child photography was prepared.

(Physical Properties of Toner B for Electrophotography) The toner B for electrophotography thus obtained was dissolved in a THF-soluble component and measured by gel permeation chromatography.
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
The specific number average molecular weight is 5000, and the specific weight average molecular weight is 1
30,000, specific molecular weight peaks are 9000 and 1400
It was 000. The ratio of the low molecular weight component in the electrophotographic toner B was 60% by weight, and the amount of the gel component insoluble in THF was 20% by weight. Furthermore, 100 ℃
The melt viscosity at 5 ° C. was 5 × 10 ⁶ Pa · s, and the melt viscosity at 110 ° C. was 8 × 10 ⁵ Pa · s.

[0041] [Toner C for electrophotography] (Composition of toner C for electrophotography) ・ Polyester resin (A: terephthalic acid / b: fumaric acid / c: bisphenol A propylene oxide Deadduct / d: Polycondensation product of bisphenol A ethylene oxide adduct, Polycondensation molar ratio; a: b: c: d = 80: 20: 50: 50, number average molecular weight 300 0, weight average molecular weight 5000, molecular weight peak 5000) ... 45% by weight ・ Polyester resin (A: terephthalic acid / b: trimellitic anhydride / c: dodecenyl succinic acid / d: Bisphenol A propylene oxide adduct / e: Bisphenol A ethylene Polycondensation product of oxide adduct, polycondensation molar ratio; a: b: c: d: e = 85 : 10: 5: 50: 50, number average molecular weight 6000, weight average molecular weight 60000, Molecular weight peak 10000, gel component 35% by weight) ... 25% by weight ・ Titanium oxide (CR60, Ishihara Sangyo) ... 30% by weight

(Method of Manufacturing Toner C for Electrophotography) Each of the above
Pre-mix the ingredients thoroughly with a Henschel mixer and mix.
Melt and knead with a strander, cool and put in a jet mill.
Perform finer pulverization and then classify twice with a wind-powered classifier
A white toner C having a volume average particle diameter of 8.0 μm was obtained. This
100 parts by weight of white toner C particles and BE as an external additive
T specific surface area 100 m ²/ G of hydrophobic titanium oxide fine particles
Mix 0.6 parts by weight with a Henschel mixer and charge.
A toner C for child photography was prepared.

(Physical Properties of Toner C for Electrophotography) The toner C for electrophotography thus obtained was dissolved in a THF-soluble component and measured by gel permeation chromatography.
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
Specific number average molecular weight is 2000, specific weight average molecular weight is 4
0000, specific molecular weight peaks are 2500 and 20000
It was 0. The ratio of the low molecular weight component in the electrophotographic toner C was 70% by weight, and the amount of the gel component insoluble in THF was 8% by weight. Furthermore, the melt viscosity at 100 ° C. was 2 × 10 ⁵ Pa · s, and the melt viscosity at 110 ° C. was 2 × 10 ⁴ Pa · s.

[0044] [Toner D for electrophotography] (Composition of electrophotographic toner D) ・ Polyester resin (A: terephthalic acid / b: fumaric acid / c: bisphenol A propylene oxide Deadduct / d: Polycondensation product of bisphenol A ethylene oxide adduct, Polycondensation molar ratio; a: b: c: d = 80: 20: 50: 50, number average molecular weight 300 0, weight average molecular weight 5000, molecular weight peak 5000) ... 56% by weight ・ Polyester resin (A: terephthalic acid / b: trimellitic anhydride / c: dodecenyl succinic acid / d: Bisphenol A propylene oxide adduct / e: Bisphenol A ethylene Polycondensation product of oxide adduct, polycondensation molar ratio; a: b: c: d: e = 85 : 10: 5: 50: 50, number average molecular weight 6000, weight average molecular weight 60000, Molecular weight peak 10000, gel component 35 wt%) 32 wt% -C. I. Pigment Red 122 / C.I. I. Pigment Red 57: 1 = 3/2 ... 12% by weight

(Preparation Method of Toner D for Electrophotography) The above components are sufficiently premixed with a Henschel mixer, melt-kneaded with an extruder, cooled and then finely pulverized with a jet mill, and further 2 with a wind classifier. Batch classification was performed to obtain a magenta toner D having a volume average particle diameter of 8.0 μm. 100 parts by weight of the magenta toner D particles and 0.6 parts by weight of hydrophobic titanium oxide fine particles having a BET specific surface area of 100 m ² / g as an external additive are mixed in a Henschel mixer to prepare an electrophotographic toner D. did.

(Physical Properties of Toner D for Electrophotography) The toner D for electrophotography thus obtained was dissolved in a THF-soluble component and measured by gel permeation chromatography.
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
Specific number average molecular weight is 2000, specific weight average molecular weight is 4
0000, specific molecular weight peaks are 2500 and 20000
It was 0. The ratio of the low molecular weight component in the electrophotographic toner D was 70% by weight, and the amount of the gel component insoluble in THF was 8% by weight. Furthermore, the melt viscosity at 100 ° C. was 4 × 10 ⁵ Pa · s, and the melt viscosity at 110 ° C. was 9 × 10 ⁴ Pa · s.

[0047] [Toner E for electrophotography] (Composition of electrophotographic toner E) ・ Polyester resin (A: terephthalic acid / b: fumaric acid / c: bisphenol A propylene oxide Deadduct / d: Polycondensation product of bisphenol A ethylene oxide adduct, Polycondensation molar ratio; a: b: c: d = 80: 20: 50: 50, number average molecular weight 300 0, weight average molecular weight 5000, molecular weight peak 5000) ... 94% by weight ・ Carbon black (# 25B, Mitsubishi Chemical): 6% by weight

(Method of Manufacturing Toner E for Electrophotography) Each of the above
Pre-mix the ingredients thoroughly with a Henschel mixer and mix.
Melt and knead with a strander, cool and put in a jet mill.
Perform finer pulverization and then classify twice with a wind-powered classifier
A black toner E having a volume average particle diameter of 8.0 μm was obtained. This
100 parts by weight of black toner E particles and BE as an external additive
T specific surface area 100 m ²/ G of hydrophobic titanium oxide fine particles
Mix 0.6 parts by weight with a Henschel mixer and charge.
A toner E for child photography was prepared.

(Physical Properties of Electrophotographic Toner E) By dissolving the obtained electrophotographic toner E in a THF-soluble component and measuring by gel permeation chromatography,
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
Specific number average molecular weight is 2500, specific weight average molecular weight is 4
500, the specific molecular weight peak was 4500. Also,
The ratio of the low molecular weight component in the electrophotographic toner E is 9
The amount of the gel component insoluble in THF was 0% by weight.

[0050] [Toner F for electrophotography] (Composition of toner F for electrophotography) ・ Polyester resin (A: terephthalic acid / b: trimellitic anhydride / c: dodecenyl succinic acid / d: Bisphenol A propylene oxide adduct / e: Bisphenol A ethylene Polycondensation product of oxide adduct, polycondensation molar ratio; a: b: c: d: e = 85 : 10: 5: 50: 50, number average molecular weight 6000, weight average molecular weight 60000, Molecular weight peak 10000, gel component 35% by weight) ... 94% by weight ・ Carbon black (# 25B, Mitsubishi Chemical): 6% by weight

(Method of Manufacturing Toner F for Electrophotography) Each of the above
Pre-mix the ingredients thoroughly with a Henschel mixer and mix.
Melt and knead with a strander, cool and put in a jet mill.
Perform finer pulverization and then classify twice with a wind-powered classifier
A black toner F having a volume average particle size of 8.0 μm was obtained. This
100 parts by weight of black toner F particles and BE as an external additive
T specific surface area 100 m ²/ G of hydrophobic titanium oxide fine particles
Mix 0.6 parts by weight with a Henschel mixer and charge.
A toner F for child photography was prepared.

(Physical properties of electrophotographic toner F) The obtained electrophotographic toner F is dissolved in a THF-soluble component and measured by gel permeation chromatography.
The specific number average molecular weight, the specific weight average molecular weight, and the specific molecular weight peak in the THF-soluble matter were determined. as a result,
Specific number average molecular weight is 5500, specific weight average molecular weight is 5
The peak was 5000 and the specific molecular weight was 9500. The ratio of the low molecular weight component in the electrophotographic toner F was 50% by weight, and the amount of the gel component insoluble in THF was 30% by weight.

[Evaluation of pulverizability of electrophotographic toner] The pulverizability of the above-mentioned electrophotographic toners A to F during production was evaluated. The pulverizability can be expressed by the amount of toner that can be pulverized per unit time. For each of the electrophotographic toners A to F, an air pressure of 588 Pa (6 kgf / c
The pulverizability in m ² ) was evaluated, and a case of 20 kg / h or more was judged as good (◯), and a case of 20 kg / h or less was judged as bad (x). The results are shown in Table 1.

[0054]

[Table 1]

[Examples 1 to 4 and Comparative Examples 1 to 5] Two-component developers A to F were prepared on the image recording medium using the above electrophotographic toners A to F and the carriers shown below. Was prepared, and an image part and a background part were formed from the two-component developers A to F to obtain display bodies of Examples 1 to 4 and Comparative Examples 1 to 5. Electrophotographic toner A used for forming image portion and background portion
F is as shown in Table 2 below.

[Production of Carrier] (Carrier Composition) Ferrite Particles (Electrical Resistance: 1 × 10 ⁹ Ω · cm) 100 parts by weight Toluene 14 parts by weight Perfluorooctylethyl acrylate / methyl Methacrylate copolymer (copolymerization ratio 40:60, weight average molecular weight Mw: 50,000) ... 1.6 parts by weight-carbon black (VXC-72; manufactured by Cabot Corporation) ... 0.12 parts by weight-crosslinking Melamine resin (volume average particle size; 0.3 μm) ... 0.3 parts by weight

(Production Method of Carrier) The above components except ferrite particles were dispersed by a sand mill for 1 hour to prepare a film forming liquid, and the film forming liquid and ferrite particles were put in a vacuum degassing type kneader, and 60 After stirring at 30 ° C. for 30 minutes, the pressure was reduced and toluene was distilled off to form a film on the surface of the ferrite particles to prepare a carrier.

[Preparation of Two-Component Developer] Two-component developer A was prepared by mixing 6 parts by weight of the electrophotographic toner A and 94 parts by weight of the carrier. With respect to the electrophotographic toners B to F, the two-component developer B to
F was produced.

Using a two-component developer A to F, an electrophotographic copying machine (manufactured by CDT60 Fuji Xerox Co., Ltd.) under the TMA conditions shown in Table 2 on a polyethylene terephthalate film having a thickness of 150 μm as an image recording medium. The image portion and the background portion as the display bodies A to F for the vehicle-mounted meter panel were formed.

The transmission densities of the image portion and the background portion were measured by a reflectance / transmittance meter HR100 manufactured by Murakami Color Research Laboratory. Immediately after the image formation, and by mounting the vehicle-mounted meter panel formed as described above on the Assy body, at 20 ° C. at 20 ° C.
After the 0-hour high temperature storage test, the image quality of both images was visually evaluated. The results are also shown in Table 2.

Further, the display bodies A to F on which the toners of the image portion and the background portion are fixed were subjected to heat treatment at a predetermined temperature and time in a constant temperature bath. Table 2 shows the conditions for the heat treatment. In addition, the pinhole ratios of the displays A to F were evaluated by the same method as described above, and the evaluation results are also shown in Table 2.

[0062]

[Table 2]

According to Table 2, the display bodies of Examples 1 to 4 are
The excellent effect that the pinhole ratio was small and the image quality was good both at the beginning of the test and after the test was observed. On the other hand, since the display bodies of Comparative Examples 2 to 5 were not subjected to the heat treatment, they had a large pinhole ratio and had a problem in practical use of the display bodies. Further, in Comparative Example 1, since the heat treatment is performed, the pinhole ratio is small, but the black toner E used for forming the background portion has a specific molecular weight peak only in the low molecular weight region. , The image quality after the test was distorted. Similarly, in the display body of Comparative Example 4 using the black toner E, the image quality after the test was also distorted.

[0064]

According to the present invention, in a display body in which an image portion and a background portion are formed by an electrophotographic method, pinholes in the image portion and the background portion are reduced, and the image is formed even at a high temperature of about 100 ° C. It is possible to provide a display body which does not disturb.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI Theme Coat (reference) G03G 9/08 333 (72) Inventor Yoshifumi Iida 1600 Takematsu, Minamiashigara-shi, Kanagawa Fuji Xerox Co., Ltd. ( 72) Inventor Teruhiko Iwase 1-1, Showa-cho, Kariya city, Aichi F-term in DENSO CORPORATION (reference) 2H005 AA01 AA21 CA03 CA04 CA07 CA08 CA09 CA12 CA13 CA15 EA06 2H033 AA03 AA10 AA47 BA11 BA12 BA25 BA26 BA27 BA59 BB18 CA30 CA44

Claims (4)

[Claims] 1. A display body comprising an image portion and a background portion formed by color toner and black toner on an image recording medium by electrophotography, wherein the color toner and the black toner are respectively TH
According to gel permeation chromatography in the F-soluble content, satisfying that the number average molecular weight is 1000 to 6000, the weight average molecular weight is 30,000 to 150,000, and the molecular weight range of 1,000 to 10,000 and the molecular weight range of 100,000 to 1500000 are satisfied. A display having a peak in the molecular weight distribution in each, and the ratio of pinholes per unit area in the image portion and the background portion is 1 × 10 ⁻³ % or less. 2. The color toner on the image recording medium
-And both images of the image part and background part with the black toner
After fixing, the melt viscosity of both toners is 1 × 10. ⁷~ 1 x 1
0³It is heat-treated at a temperature in the range of Pa · s.
The display according to claim 1, wherein: 3. The display according to claim 1, wherein the image recording medium is a transparent plastic film. 4. The color toner and the black toner are both
At least one binder resin, which is selected from polyester resin, polystyrene resin, styrene-acrylic resin, epoxy resin, silicone resin, polyurethane resin, polyamide resin, and polyolefin resin. It is a resin, The display body in any one of Claims 1-3.