JP2003005432A - Electrophotographic full color toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a full color toner having gloss and transparency and realizing both of low temperature fixing property and hot offset resistance. SOLUTION: The electrophotographic full color toner contains at least a resin A, a resin B and wax. These components form a sea-island phase separation structure in an insoluble state with one another and satisfy the following conditions (1) to (5). (1) The sea-island phase separation structure has the island- like resin B dispersed in the sea-like resin A as a continuous phase, and the wax is substantially encapsulated in the island-like resin B. (2) The binder resin in the toner does not have a THF insoluble component. (3) The resin A is essentially a polyester and/or polyol and the resin B is a copolymer resin of styrene and methylacrylate and/or methylmethacrylate. (4) The contents of the resin A, B and wax are in the relation of resin A>resin B>=wax. (5) The wax content ranges from 2 wt.% to 15 wt.%.

Description

Detailed Description of the Invention

[0001]

2. Description of the Related Art In electrophotographic toner, a contact heating fixing method is widely adopted in order to fix the visualized toner on a recording medium. In this fixing method, it is desired that the fixing is sufficiently performed at a low temperature and the offset does not occur even at a high temperature. Further, in the case of full-color toner, it is desired that the toners of respective colors are sufficiently melted to mix colors and have gloss and transparency. In response to such requirements, a vinyl resin represented by a styrene-acrylic copolymer, which has been widely used in the past, can be easily obtained as a low molecular weight one having excellent low-temperature fixability, and further, offset resistance. Polyester resin and polyol resin, which have excellent storage stability, are used. In particular, polyester resins and polyol resins are widely used in full-color toners in which a lower molecular weight is desired in terms of gloss and transparency.

In recent years, from the tendency of space saving and cost reduction, as a means for preventing an offset phenomenon at the time of fixing, a method is provided in which a releasing oil tank is provided and oil is supplied to the surface of the fixing member from there. However, the method has changed to a method in which a substitute for a releasing oil such as wax is contained in the toner.

The releasability when a wax is contained in the toner is greatly affected by the dispersed state of the release agent in the toner. When the wax is compatible with the binder resin, it does not exhibit the original melting point of the wax and the releasability cannot be expressed. Therefore, it is necessary that the wax that is incompatible with the binder resin exists in a dispersed state.

When the release agent has a large dispersion diameter, stress is likely to be concentrated on the interface between the wax and the binder resin during pulverization, and the probability of the presence of the wax on the surface of the toner particles increases. Therefore, in terms of releasability, a larger wax dispersion diameter is more advantageous. However, when the wax dispersion diameter becomes large, problems such as deterioration of developability due to deterioration of toner fluidity and deterioration of transferability are likely to occur. In addition, problems with developability and transferability are more likely to occur, such as the wax fusing to the carrier or the photoreceptor over time, and the external additive on the toner surface being easily embedded.

Polyester resins and polyol resins have a poor compatibility with general waxes as compared with styrene-acrylic copolymers, so that the dispersed state of the wax is likely to be large. In particular, a low molecular weight resin suitable for a full-color toner cannot be expected to have a dispersion effect due to the resin shearing force at the time of kneading, and the dispersed state of wax tends to be larger than that of a monochrome toner. Further, the polyester resin and the polyol resin have a strong internal cohesive force and are inferior in pulverizability as compared with the styrene-acrylic copolymer. Therefore, of course, the productivity tends to deteriorate, but even if the wax dispersion state is the same, as in the case of the styrene-acrylic copolymer resin, the portion other than the interface between the wax and the resin is the crushed surface. Is less likely to occur, and the wax is more likely to be present on the surface of the toner particles.

[0006] Examples of conventional techniques aimed at addressing the above-mentioned problems include JP-A-5-188636, JP-A-6-250432, and JP-A-9-127718. A toner having a function of improving the dispersion of the wax is contained in the toner. Although the wax dispersion diameter can be reduced by the above-mentioned technique, if the dispersion diameter is so small that there is no side effect due to the wax dispersion, the amount of wax existing in the vicinity of the surface of the toner particles becomes small, and it is difficult to obtain a sufficient releasing effect. .

A toner containing a wax produced by a polymerization method has also been proposed (Japanese Patent Laid-Open No. 07-084407). According to this toner, problems such as deterioration of developability, transferability, and durability do not easily occur even if the dispersed diameter of the wax is large, but when the wax does not exist near the particle surface, the wax exudes from the toner. It is difficult to obtain releasability.

On the other hand, as a heat fixing method, a belt heating fixing method has been proposed in addition to the heat roller fixing method which has been frequently used. In this fixing method, there was a wait time until the heat roller reached a predetermined temperature, which was a problem of the heat roller fixing method, heating to maintain the temperature of the heating roller against passage of recording material and external factors There is no need for a large heat capacity of the body or heating roller. Further, since the belt does not have a large curvature like a roller, offset and winding at the time of paper discharge are reduced. Further, since there is a distance between the position of the heating body of the belt and the position of the paper discharge, it is possible to lengthen the nip time and preheat the toner, so that the fixing temperature can be lowered. However, there is a case in which the releasability is insufficient in the belt fixing due to the preheating of the toner and the long nip time, which are in the above techniques. In the case of JP-A-11-072956 containing an incompatible petroleum resin having a low molecular weight, there is no problem in heat roller fixing, but an incompatible petroleum resin having a low molecular weight tends to be offset in belt heat fixing. Further, the belt is thin in order to take advantage of the small heat capacity, and the pressure at the time of fixing is low in order to prevent the belt from becoming more wrinkled. Therefore, if the amount of wax existing near the surface is small, even if the wax is sufficiently exuded by roller fixing with a high fixing pressure, it may be insufficient by the belt (JP-A-7-084407).

Since the styrene resin disperses the wax more easily than the polyester resin, there is an example in which the styrene resin is used as a wax dispersant in the polyester resin (JP-A-7-28725). Further, there is also a toner using a toner obtained by polymerizing a styrene resin or a resin in which a wax is further dispersed in a polyester resin in the same system by some reaction (Japanese Patent Application Laid-Open No. HEI 7-18753).
-098518, JP-A-11-352720, etc.).

In such a case, a resin in which wax is uniformly dispersed is obtained, but when this is kneaded with other materials, the dispersed wax may re-aggregate, in which case the dispersed state. Becomes uneven. However, in general, when a non-compatible toner is contained in a full-color toner, gloss and transparency are deteriorated. Although it does not pose a problem for monochrome toners, it may cause problems for gloss and transparency for full-color toners depending on the type and content of the styrene resin described in the above examples.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and its object is to provide a full color toner for electrophotography having the following characteristics. 1. A toner that has both low-temperature fixability and hot offset resistance, and can obtain gloss and transparency suitable for full-color toner,
To provide a toner with gloss and transparency suitable for full-color toner, especially in belt heating and fixing. 2. Provided is a toner containing a wax-containing toner, in which the fluidity is not deteriorated, the developability and transferability are good, and a good image is obtained. 3. Also for wax-containing toners, a toner that has a small amount of wax spent on a charging member such as a carrier or a developing roller, has good developability and transferability for a long period of time, and can provide a good image. 4. Providing toner with good heat resistance and storage stability. 5. Providing a toner that has good pulverizability but does not become over-pulverized and is not easily pulverized even in a developer, so that the generation of fine powder causes less background stain.

[0012]

[Means for Solving the Problems] By using a styrene-acrylic resin to disperse a wax in a polyester resin that easily achieves both low-temperature fixability and offset resistance, the release agent exhibits releasability. It has been found that the toner can be made in a size that is easy to use and has few side effects due to the inclusion of a release agent. Furthermore, by using a specific acrylic type of the resin, there is little deterioration in gloss and transparency. Based on this, the present invention could be reached.

That is, the present invention comprises at least resin A, resin B and wax, which are incompatible with each other and have a sea-island phase-separated structure, and the following conditions (1) to (5): By providing a full-color toner for electrophotography, the above-mentioned problems can be solved. (1) The sea-island phase-separated structure is a structure in which a resin B is dispersed in an island-like resin A that is a continuous phase and the wax is substantially included in the island-shaped resin B. thing. (2) The binder resin in the toner has no THF insoluble content. (3) The resin A is mainly polyester and / or polyol, and the resin B is a copolymer resin of styrene and methyl acrylate and / or methyl methacrylate. (4) The content of resin A, resin B, and wax is resin A>
Resin B ≧ wax. (5) The wax content is 2 to 15% by weight.

The toner is formed by visualizing an electrostatic latent image on a photoconductor with toner and transferring the obtained toner image onto a transfer medium, and then the toner image is formed by contacting the toner image with an endless belt or an endless belt. It is a toner used in an image forming method for fixing. In the toner, the content of the resin B is 20% by weight or less, preferably 15% by weight or less, the resin B has a glass transition point higher than that of the resin A,
The toner has a peak molecular weight in the molecular weight distribution by GPC of THF-soluble content of 5000 or more and a ratio of the weight average molecular weight to the number average molecular weight of 4 or less, preferably 2 to 3.5.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. One of the characteristics of the toner of the present invention is that it contains at least two kinds of resins and waxes, and they are incompatible with each other and have a sea-island phase separation structure. In other words, the other resin B is dispersed in a state of being substantially contained in the island-shaped resin B. Generally, if there is an incompatible interface in the crushing, the crushing stress is likely to be concentrated there. In many toners, the resin and the wax are incompatible so that the wax exudes from the toner, and is easily crushed at the interface between the resin and the wax. As a result, the wax is exposed to the surface of the crushed toner more than the added wax, which causes a decrease in transferability and durability.

In the toner of the present invention, the resin B is dispersed like islands in the sea-like resin A, and the wax is included in the island-shaped resin B, so that the resin A and the resin B are incompatible with each other. The crushing stress can be concentrated also on the interface, the amount of wax exposed on the crushed toner surface can be reduced, and the toner having excellent transferability and durability can be obtained. Even if the wax is not exposed on the surface of the toner, it is present in the vicinity of the surface, so that the offset resistance is hardly deteriorated. The wax in the toner of the present invention is substantially included in the island-shaped resin B. If a small number of waxes are contained in the resin B and are dispersed in the resin A, the presence of the wax on the particle surface is not increased.

In the above-mentioned island-shaped toner,
The resin A constituting the sea is a polyester and / or polyester (hereinafter referred to as a polyester resin) having a relatively poor grindability, and the resin B constituting an island is a styrene-acryl copolymer (hereinafter referred to as a polyester) having a better grindability than the polyester resin. By using a styrene resin), not only the interface between incompatible substances but also pulverization inside the styrene resin occurs. Therefore, the pulverizability is further improved. However, since the content of the styrene-based resin is smaller than the content of the polyester-based resin, over-pulverization does not occur and it is possible to suppress the generation of a large amount of fine powder. Further, since the pulverization occurs inside the resin forming the islands, the amount of wax present on the surface is further reduced. However, as compared with the case where the wax is crushed at the interface between the resin that constitutes the island and the resin that constitutes the sea, the wax will be present closer to the surface.

In order to surely form the structure of the present invention and achieve the object, the content of resin and wax in the toner is such that resin A> resin B ≧ wax. When the content of the resin B is less than the wax content, the wax dispersion diameter tends to be large, and the transferability and durability are deteriorated. If the amount of resin A is less than that of resin B, the toner structure of the present invention may not be formed. In addition, the good characteristics of the polyester resin are not easily expressed. It is important that the wax content is 2 to 15% by weight based on the total amount of the resin and wax in the toner. If the amount of wax is less than 2% by weight, the releasing effect is insufficient. If the amount of wax is more than 15% by weight, the wax dispersion diameter becomes large, and the gloss and transparency are lowered. To some extent, the wax dispersion diameter becomes smaller as the amount of resin B is larger than the amount of wax. However, the addition of the incompatible resin B lowers the transparency and gloss, and the resin B has a good pulverizability, so if it is too much, it is over-pulverized. The more preferable resin B content is 20% by weight or less based on the total amount of the resin and wax in the toner.

Generally, when incompatible substances are mixed, gloss and transparency are deteriorated. Since the polyester-based resin and the styrene-based resin are incompatible with each other, gloss and transparency are likely to be lowered. In the present invention, S is used among general styrene resins.
By setting the acrylic value to be methyl acrylate and / or methyl methacrylate, which has a P value close to that of polyester resin, gloss can be obtained even if incompatible substances are included.
A decrease in transparency can be suppressed. When the acrylic species is methyl acrylate and / or methyl methacrylate, the thermal characteristics of the polyester are likely to be approximated, and the low-temperature fixability and internal cohesive force of the polyester are not significantly impaired.

In the present invention, the probability that the styrene resin will come to the surface of the particles is high. Therefore, preservability can be improved by making the glass transition point of this styrene resin higher than that of the polyester resin. However, when the glass transition point of the styrene resin is high and the molecular weight is too high, the low temperature fixability of the polyester resin is impaired and the gloss and transparency are lowered. In order not to impair the fixing properties of the polyester resin, it is preferable not to include a high molecular weight component. On the other hand, when the nip time is long such as belt heating and fixing, or the toner is preheated, the offset tends to occur if there is a low molecular weight component incompatible with the polyester resin.
Therefore, when a styrene-based resin with a high glass transition point is contained, it should have a molecular weight that is not too low and a sharp molecular weight distribution to improve storage stability without impairing the low-temperature fixability of the polyester-based resin. Can be made. Such a styrene resin has a peak molecular weight of 500.
0 or more, preferably 5000 to 9000, and the ratio of the weight average molecular weight to the number average molecular weight is 4 or less, preferably 2
~ 3.5.

Further, the toner of the present invention contains T in the binder resin.
It is preferable that there is no HF insoluble matter. T at the raw resin stage
Even if there is HF insoluble matter, T
It is sufficient if there is no HF insoluble matter. When THF is insoluble, it is difficult to obtain gloss and transparency suitable for full-color toner. The THF-insoluble matter in the present invention was measured as follows. 1.0 g of the toner is weighed, 50 g of THF is added thereto, and the mixture is allowed to stand at 20 ° C. for 24 hours. This is JIS standard (P
3801) Filter at room temperature using a quantitative filter paper of Type 5C.
The dry back paper residue is weighed and expressed as a ratio (% by weight) of the used toner and filter paper residue. In the filter paper residue, solids such as pigments and waxes if the wax is insoluble in THF are present. Therefore, they are separately determined by thermal analysis.

In the toner of the present invention, THF is used.
It is preferable that there is no insoluble matter, but a THF insoluble matter of about wt% may be present.

The toner has a softening point of 105 to 135.
C is preferred. More preferably, it is 110-130 degreeC. If it is higher than this, it is difficult to obtain gloss and transparency, and if it is lower than this, the margin for offset tends to be small. For the same reason, the toner THF
The weight average molecular weight Mw of the soluble component by GPC is 8000.
~ 40,000, more preferably 12,000 to 30,000
Is. Further, the glass transition point Tg of the toner is 55 to 75 ° C.
Is preferred. If it is lower than this, it is difficult to obtain a sufficient storability, and if it is higher than this, fixing at low temperature is difficult.

The softening temperature is the elevated flow tester (CT
F-500: manufactured by Shimadzu Corporation), the diameter of the die pores is 0.5 mm, the pressure is 10 kg / cm ² , and the heating rate is 3 ° C./m.
The temperature corresponds to 1/2 of the height from the outflow start point to the outflow end point when 1 cm ³ of the sample is melted and flowed out under the condition of in.

The peak molecular weight Mp of the molecular weight distribution and the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn are measured by GPC as follows. Stabilize the column in a 40 ° C. heat chamber and allow THF as solvent to flow through the column at this temperature at a flow rate of 1 ml / min.
The measurement is performed by injecting 200 μl of a THF sample solution of the toner base adjusted to a sample concentration of 0.05 to 0.6% by weight. Before injecting the THF sample solution, a THF insoluble component is removed with a 0.45 μm liquid chromatography filter. In measuring the molecular weight of the toner sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value and the count number of a calibration curve prepared using several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for creating a calibration curve, for example,
Pressure Chemical Co. Alternatively, the molecular weight manufactured by Toyo Soda Kogyo Co., Ltd. is 6 × 10 ² , 2.1.
× 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 1
0 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ ,
It is suitable to use 2 × 10 ⁶ , 4.48 × 10 ⁶ and use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

The Tg of the binder resin is Rig manufactured by Rigaku Denki Co., Ltd.
It is measured by an aku THRMOFLEX TG8110 at a temperature rising rate of 10 ° C./min.

The volume average particle diameter of the toner base particles is 4 to.
It is preferably 10 μm. If the particle size is smaller than this, it may cause scumming at the time of development, deteriorate fluidity, and hinder toner replenishment and cleaning properties. Further, the toner may be fused to the developing roller or the developer coating blade. On the contrary, if the particle size is larger than this, dust during development, deterioration of resolution, etc. may become a problem. The volume average particle diameter is the Coulter Counter Model TA- manufactured by Coulter Electronics Co.
It is the value measured by II.

The material of the toner used in the present invention is polyester resin and / or polyol resin as the resin A constituting the sea, and styrene-resin B as the resin B constituting the island.
All of the known acrylic copolymers can be used except that the acrylic species is methyl acrylate and / or methyl methacrylate.

As the polyester resin used in the present invention, all the resins obtained by the polycondensation reaction of a generally known alcohol and acid can be used. For example, as alcohol, polyethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-propylene glycol, neopentyl glycol, 1,4
-Diols such as butenediol, 1,4-bis (hydroxymethyl) cyclohexane, bisphenol A,
Etherified bisphenols such as hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxypropyleneized bisphenol A, etc., and divalent alcohol units obtained by substituting these with a saturated or unsaturated hydrocarbon group having 3 to 22 carbon atoms. , Other dihydric alcohol units, sorbitol, 1,2,3,6-hexanetetrol, 1,4-salbitan, pentaethritol dipentaethritol, tripentaethritol, sucrose, 1,
2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3.
Highly trivalent or higher alcohol monomers such as 5-trihydroxymethylbenzene.

The carboxylic acid used to obtain the polyester resin includes, for example, palmitic acid, stearic acid, oleic acid and other monocarboxylic acids, maleic acid, fumaric acid, mesaconic acid, citraconic acid, terephthalic acid, cyclohexanedicarboxylic acid. Acid, succinic acid, adipic acid, sebacic acid, malonic acid, these have 3 to 22 carbon atoms
Divalent organic acid monomers substituted with saturated or unsaturated hydrocarbon groups, anhydrides of these acids, dimers of lower alkyl esters and linoleic acid, 1,2,4-benzenetricarboxylic acid, 1 , 2,5-benzenetricarboxylic acid,
2,5,7-naphthalene tricarboxylic acid, 1,2,4-
Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,
Trivalent compounds such as 3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid embol trimer acid, and anhydrides of these acids. The polyvalent carboxylic acid monomers described above are used.

As the polyol resin, various types can be used, and as the one used in the present invention,
The following are particularly preferred. Particularly, as a polyol resin, an epoxy resin, an alkylene oxide adduct of a dihydric phenol or a glycidyl ether thereof, a compound having one unique active hydrogen that reacts with an epoxy group in the molecule, and an active hydrogen that reacts with an epoxy group in the molecule It is preferable to use a polyol obtained by reacting a compound having two or more of the above.

The acrylic component of the styrene-acrylic copolymer is methyl acrylate and / or methyl methacrylate. As styrene, styrene and its derivatives, for example, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene,
Examples thereof include alkyl styrenes such as octyl styrene, fluorostyrenes, chlorostyrenes, bromostyrenes, dibromostyrenes, halogenated styrenes such as iodostyrenes, and nitrostyrenes, acetylstyrenes, methoxystyrenes and the like.

As the resin used in the present invention, one of these monomers or a polymer of two or more of them can be used. Other resins can be mixed and used as long as they are compatible with the resin A to the extent that the characteristics of the polyester resin of the resin A are not impaired.

Examples of the wax as a release agent include low molecular weight polyolefin wax such as low molecular weight polyethylene and low molecular weight polypropylene, synthetic hydrocarbon wax such as Fischer-Tropsch wax, beeswax, carnauba wax and candelilla wax. , Natural waxes such as rice wax and montan wax, petroleum waxes such as paraffin wax and microcrystalline wax, higher fatty acids such as stearic acid, palmitic acid and myristic acid, metal salts of higher fatty acids, higher fatty acid amides and the like. Examples include various modified waxes.

These may be used alone or in combination of two or more, but it is preferable to use one having a melting point in the range of 70 to 125 ° C. When the melting point is 70 ° C. or higher, a toner having excellent transferability and durability can be obtained, and when the melting point is 125 ° C. or lower, the toner is rapidly melted at the time of fixing and a reliable releasing effect can be exhibited. The amount of these release agents used is preferably 2 to 15% by weight with respect to the toner. If the amount is less than 2% by weight, the offset prevention effect is insufficient, and if the amount is more than 15% by weight, the transferability and durability are deteriorated.

The dispersion diameter of the wax in the toner is preferably at most ½ or less of the major axis diameter of the toner from the viewpoint of transferability and durability. However, when the maximum dispersed particle diameter of the wax is 0.5 μm or less in the major axis diameter, the wax is less likely to exude at the time of fixing and the offset prevention effect becomes insufficient.

Examples of the colorant include carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow and poly. Azo Yellow, Oil Yellow, Hansa Yellow (GR, A,
RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Balkan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Red iron oxide, red lead,
Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline Red, Resor Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carn Min BS, Permanent Red (F2R, F4R, FRL,
FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G,
Resor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B,
Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil. Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkali Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine, Navy Blue, Anthraquinone Blue, Fast Ioretto B, methyl violet lake, cobalt violet, manganese violet, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, viridian, emerald green, Pigment Green B, Naphthol Green B, green gold, acid green lake,
Malachite green lake, phthalocyanine green,
Anthraquinone green, titanium oxide, zinc oxide, lithobon and mixtures thereof can be used. The amount used is generally 0.1 to 50 parts by weight with respect to 100 parts by weight of the binder resin.

In the present invention, the toner may optionally contain a charge control agent. Specific examples of the charge control agent include metal complex salts of monoazo dyes, nitrohumic acid and its salts, quaternary ammonium salts, imidazole metal complexes and salts, salicylic acid, naphthoate salts, dicarboxylic acid Co, Cr, and Metal complex amino compounds such as Fe, organic boron salts, calixarene compounds, organic dyes, etc. can be used, but from these, a transparent to white substance that does not impair the color tone of the color toner is added to obtain a negative polarity. Alternatively, it is preferable to stabilize and impart the toner to the positive polarity.

The amount of the charge control agent used in the present invention is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. However, it is preferably 0.1 to 100 parts by weight of the binder resin.
Used in the range of 10 parts by weight. The preferred range is 2 to 5 parts by weight. If the amount is less than 0.1 parts by weight, the toner is insufficiently charged, which is not practical. When the amount is more than 10 parts by weight, the chargeability of the toner is too large and the electrostatic attraction with the carrier is increased, so that the fluidity of the developer is lowered and the image density is lowered.

To introduce the magnetic material into the toner particles, iron oxides such as ferrite, magnetite and maghematite, metals such as iron, cobalt and nickel, or magnetic components such as alloys of these with other metals are used. They can be used alone or in combination. Also in this case, it is preferable to select a white substance from a transparent color that does not impair the color tone of the color toner.

In the toner of the present invention, fine particles of hydrophobized silica, titanium oxide or the like are preferably externally added to the toner base, but in addition to these, hydrophobized alumina or resin fine particles, or A lubricant such as an aliphatic metal salt or polyvinylidene fluoride fine particles can also be used together. In particular, by using both hydrophobized silica and hydrophobized titanium oxide in combination, by increasing the externally added amount of hydrophobized titanium oxide to be greater than the externally added amount of hydrophobized silica, transferability and humidity can be improved. It is possible to obtain a toner excellent in the stability of charging with respect to.

The following are typical examples of the hydrophobizing agent used here. Dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, allyldimethyldichlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, p-chloroethyltrichlorosilane,
Chloromethyldimethylchlorosilane, chloromethyltrichlorosilane, p-chlorophenyltrichlorosilane,
3-chloropropyltrichlorosilane, 3-chloropropyltrimethoxysilane, vinyltriethoxysilane,
Vinylmethoxysilane, vinyl-tris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinyldichlorosilane, dimethylvinylchlorosilane, octyl-trichlorosilane, decyl-trichlorosilane,
Nonyl-trichlorosilane, (4-t-propylphenyl) -trichlorosilane, (4-t-butylphenyl)
-Trichlorosilane, dipentyl-dichlorosilane, dihexyl-dichlorosilane, dioctyl-dichlorosilane, dinonyl-dichlorosilane, didecyl-dichlorosilane, didodecyl-dichlorosilane, dihexadecyl-
Dichlorosilane, (4-t-butylphenyl) -octyl-dichlorosilane, dioctyl-dichlorosilane, didecenyl-dichlorosilane, dinonenyl-dichlorosilane, di-2-ethylhexyl-dichlorosilane, di-
3,3-Dimethylbenzyl-dichlorosilane, trihexyl-chlorosilane, trioctyl-chlorosilane, tridecyl-chlorosilane, dioctyl-methyl-chlorosilane, octyl-dimethyl-chlorosilane, (4-t
-Propylphenyl) -diethyl-chlorosilane, octyltrimethoxysilane, hexamethyldisilazane, hexaethyldisilazane, diethyltetramethyldisilazane, hexaphenyldisilazane, hexatolyldisilazane and the like. In addition to these, titanate-based coupling agents and aluminum-based coupling agents can also be used.

The toner of the present invention can be used for both one-component development and two-component development. When the toner is used as a two-component developer, it is used as a mixture with carrier powder. As the carrier in this case, all known carriers can be used, and examples thereof include iron powder, ferrite powder, magnetite powder, nickel powder, glass beads and the like, and those whose surfaces are coated with a resin or the like.

A conventionally known method can be applied to the method for producing the toner of the present invention. As a device for kneading the toner constituent materials, a batch type twin roll, a Banbury mixer or a continuous type twin screw extruder, for example, a KTK type twin screw extruder manufactured by Kobe Steel, a TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd. Machine, KCK
A twin-screw extruder manufactured by Ikegai, a PCM-type twin-screw extruder manufactured by Ikegai Iron Works, a KEX-type twin-screw extruder manufactured by Kurimoto Iron Works, and a continuous single-screw kneader such as Co-Kneader manufactured by Buss Used.

The obtained melt-kneaded product is cooled and then pulverized. For the pulverization, for example, coarse pulverization is performed using a hammer mill or a rotoplex, and further, a fine pulverizer using a jet stream or a mechanical fine pulverizer is used. A crusher or the like can be used.
It is desirable to carry out the pulverization so that the average particle diameter becomes 3 to 15 μm. In addition, the crushed product can be
The particle size is adjusted to 5 to 20 μm. If necessary, the external additive is externally added to the base toner.By mixing and stirring the base toner and the external additive with a mixer, the external additive is crushed and coated on the toner surface. It

When used in belt heat fixing, the toner of the present invention can be fixed at a temperature lower than that of heat roller fixing. In the toner of the present invention, since the wax is present in the vicinity of the surface with a certain dispersion diameter, the wax sufficiently exudes and the releasing effect can be exhibited even at a pressure lower than that of roller fixing such as belt heating fixing. Therefore, the toner of the present invention is particularly effective when fixing with a belt heat fixing device.

FIG. 1 shows an example of an apparatus for fixing the toner of the present invention. Here, R1 is made of metal (aluminum, iron, etc.)
A fixing roller in which a cored bar is coated with an elastic body (silicone rubber, etc.), and R3 is metallic (aluminum, iron, copper,
A pipe made of stainless steel or the like) A heating roller having a hollow cylindrical core metal and a heating source H inside. S is a temperature sensor for measuring the surface temperature of the fixing belt B in contact with the heating roller R3. The fixing belt B is stretched between the fixing roller R1 and the heating roller R3. The fixing belt B has a small heat capacity, and has a release layer (50 to 30 made of silicone rubber) on a substrate (having a thickness of 30 to 150 μm of nickel or polyimide).
A thickness of 0 μm or a thickness of about 10 to 50 μm made of a fluororesin) is provided. Further, R2 is a pressure roller in which a metal cored bar is covered with an elastic body, and by pressing the fixing roller R1 from below via the fixing belt B, a nip between the fixing belt B and the pressure roller R2 is obtained. Forming a part. Further, R4 is an oil application roller impregnated with oil for applying oil (silicone oil or the like) to the fixing belt. And G is
It is a guide that supports a print sheet P (paper or the like) carrying an unfixed toner image T. Further, the dimensions of each member are set according to various necessary conditions.

These are examples, and it is possible to provide a heating source inside the fixing roller R1 and the pressure roller R2. In the present invention, fixing using a fixing belt with a configuration other than this example is used. Equipment also applies.

[0049]

EXAMPLES The present invention will now be described in more detail by way of examples.

Evaluation items in this embodiment In this embodiment, the toner is yellow, magenta, or cyan.
Black and black are created, but the evaluation is magenta tona
-I did it. Crushability Toner that is roughly crushed to an average particle size of 1 mm or less
Pulverized under certain conditions with a Pneumatic IDS grinder
It was determined by the amount of treatment per unit time when crushed. ⊚: 4 kg or more, ∘: 3 to 4 kg, Δ: 1 to 3 kg,
×: less than 1 kg, black △: 4 kg or more, but a large amount of fine powder
(Allowable range except for × and black △) Wax dispersion diameter Toner particles are ultrathin sliced to 100 nm and ruthenium tetraoxide is added.
After staining with um, use a transmission electron microscope (TEM)
It was observed at a magnification of 10,000 times and photographed. ⊚: 0.5 μm to 1 μm, ◯: 1 μm to 1/3 of particle size,
Δ: 1/3 to 1/2 of particle size, x: larger than 2/1 of particle size,
Black △: smaller than 0.5 μm (x, allowable range other than black △) Heat resistant storage Put about 20g of toner in a 20ml glass bottle and tap 50 times.
After the toner is packed and the toner is hardened, the temperature is kept constant at 50 ℃.
It was left in the tank for 24 hours, and then the penetration was measured. ⊚: through, ∘: larger than 25 mm, Δ: 15 to 25 mm,
X: 15 mm or less (other than x is an allowable range) Fixability By modifying the Ricoh copier Puritail 550,
You can remove the fixing device and attach another fixing device.
And made it possible to change the fixing temperature. This
Set Ricoh type 6000 70W paper on it and
Solid images of yellow, magenta, cyan, and black,
And solid colors of green, blue, and red as intermediate colors
An image-fixed image was obtained. In addition, this copier has a solid color solid section.
0.8 ± 0.1 mg / cm²Toner will be developed
Has been adjusted. There are two types of fixing devices:
However, from fixing device A at 110 ° C., and fixing device B at 12 ° C.
Images were obtained at each temperature by increasing the temperature from 0 ° C to every 5 ° C.
Fixing device A: The fixing device shown in FIG. 1 is set under the following conditions.
What I did. Belt tension: 1.5 kg / piece Belt speed: 200 mm / sec Fixing nip width: 10 mm Fixing roller: Roller diameter: Φ38, surface material and hardness:
About 30 degrees with silicone foam (Asker C hardness) Pressure roller: Roller diameter: Φ50, surface material and hardness:
PFA tube + silicone rubber 1mm thickness about 75 degrees
(Asker C hardness), core metal diameter: Φ48 (iron, wall thickness 1 m
m) Heating roller: Roller diameter: Φ30, (aluminum, wall thickness 2
mm) Fixing belt: Belt diameter: Φ60, Base: About 40 μm thick
Nickel, release layer: Silicone rubber about 150 μm, front
Surface roughness Rz 4.1 μm, belt width: 310 mm, oil
Coating roller: Oil coating amount 0.5mg / A4 size
Tari -Fixing device B: The fixing device shown in FIG. 2 is set under the following conditions.
What I did. Linear velocity ... 140mm / sec Fixing roller: Roller diameter 60mmφ, thickness 2mm
Recon rubber is coated with 30 μm thick PFA, core metal diameter 5
6 mmφ (iron, wall thickness 2 mm), surface roughness Rz 4.5 μm Pressure roller: Roller diameter 60 mmφ, thickness 1 mm
Recon rubber is coated with 30 μm thick PFA, core metal diameter 5
8mmφ (iron, thickness 1mm) Surface pressure: 4.8 kgf / cm² Fixing nip width: 7 mm Oil application roller: Oil application amount 0.5 mg / A4 size
Per is Cold offset generation temperature: 110 ° C or less in fixing device A
Under the fixing device B, the allowable range is 120 ° C or lower Hot offset generation temperature: Cold offset generation temperature
+ 60 ° C or above is acceptable Gloss Of the images whose fixing properties were examined, 140 ° C for fixing device A,
In fixing device B, the intermediate colors blue and gray at 150 ° C
3 Density levels, Lean and Red
Measured at an incident angle of 60 ° with a gloss meter manufactured by the company.
Average out. If the glossiness is 10 or more, it is assumed to be glossy.
It transparency When the glossiness of the same image as the glossiness is checked
Of the OHP sheet (Ricoh type
A fixed image was obtained on PPC-DX). A neutral blue,
The transparency of three points, green and red, was examined. The measurement is Suga
Direct reading haze computer HGM- manufactured by Testing Machine Co., Ltd.
2DP type was used. First, the OHP with the image fixed
Insert the sheet and measure the haze, then
The value obtained by subtracting the haze factor of the toner is the toner haze factor.
And If the haze is 30% or less, it is transparent
And durability Under the same setting conditions as when examining the glossiness, 10,000 sheets of continuous
Did lint.

[0051] Example 1Toner constituent material Resin A: Polyol resin 60 parts by weight (Tg 60 ° C, no THF insoluble matter) Resin B: Styrene-methyl acrylate-methyl methacrylate copolymer (Tg59 ° C, Mp8200, Mw / Mn4.2, THF insoluble matter)                                               32 parts by weight Release agent: Ester wax (mp 75 ° C) 8 parts by weight Colorant for yellow toner ... Disazo yellow pigment (C.I. Pigment Yellow 17)                                                 5 parts by weight For magenta toner ... Quinacridone magenta pigment (C.I. Pigment Red 122)                                                 4 parts by weight For cyan toner ... Copper phthalocyanine blue pigment (C.I. Pigment Blue 15)                                                 2 parts by weight For black toner ... Carbon black 6 parts by weight Charge control agent: Salicylic acid derivative zinc salt 2 parts by weight

The above toner constituent materials were sufficiently agitated and mixed for each color with a Henschel mixer, and then melt-kneaded with a twin-screw extruder heated to 100 to 110 ° C. After allowing the kneaded product to cool, it is roughly crushed with a cutter mill, crushed with a fine crusher using a jet stream, and the volume average particle size of the base toner is adjusted to 7 ± 1 μm using a wind classifier, and each color is colored with the base. The particles were obtained. The pulverizability of this toner was good. Even so, the amount of fine powder generated was small, the loss due to classification was small, and the base colored particles having a small amount of fine powder were obtained. 0.5 parts by weight of hydrophobic silica and 0.6 parts by weight of titanium oxide were mixed with 100 parts by weight of the base colored particles by a Henschel mixer to obtain toners of yellow, magenta, cyan and black colors. From the TEM image of the thin film section of the toner, wax having a particularly large dispersion diameter could not be observed, and it was confirmed that the wax was in a good dispersion state. The storability was also good. Further, 5 parts by weight of this toner and 95 parts by weight of a carrier having an average particle size of 50 μm are mixed and stirred by a turbuler mixer to obtain a properly charged developer, and this developer is put in a developing part of a remodeling machine of Ricoh copier pretail 550. Various evaluations were performed. A fixing device B is attached to the fixing unit. The image obtained with this toner was free of background stains and density unevenness, was clear and glossy suitable for full-color images, and had good transparency. In addition, there was a sufficient margin until the offset was fixed at the low temperature. Also in the durability evaluation, a good image condition without generation of background stains and reduction in image density was maintained until 10,000 sheets were printed. The evaluation results are shown in Table 1.

Example 2 Using the same toner as in Example 1, the developer prepared in the same manner as in Example 1 was put in the developing section of a Ricoh copier Pleter 550 remodeled machine to which the fixing device A was attached and various evaluations were made. Was done. By changing the fixing method from roller fixing to belt fixing, fixing was performed at a lower temperature than in the case of Example 1.
The gloss and transparency were lower than those in Example 1, but not so much as to impair the clear image quality of the full-color toner.

[0054] Example 3Toner constituent material Resin A: Polyester resin 76 parts by weight (Tg 61 ° C, no THF insoluble matter) Resin B: the same as in Example 1 20 parts by weight Release agent: polyethylene wax (mp 100 ° C) 4 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. This toner is
Compared to the toners of Examples 1 and 2, the dispersed wax
The number of waxes is small, but they have similar wax dispersion diameters.
there were. The image obtained using this toner is
The gloss and transparency were higher than in the case of 2. Wack
The content of resin B has decreased, but the content of resin B has decreased.
It is considered that the effect obtained is great.

[0055] Example 4Toner constituent material Resin A: Polyester resin 80 parts by weight (Tg 62 ° C, no THF insoluble matter) Polyester resin 5 parts by weight (Tg 62 ° C, THF insoluble content: less than 1%) Resin B: Styrene-methyl acrylate 10 parts by weight (Tg59 ° C, Mp6400, Mw / Mn3.5, THF insoluble matter) Release agent: Carnauba wax (mp 82 ° C) 5 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. This toner is a tree
A resin with a THF insoluble content is used as part of fat A
However, there is no THF insoluble matter in the resin in the toner after kneading.
It was. The image obtained using this toner has a real Tm.
Although higher than in the case of Example 3, the gloss and transparency are the same as in Example 3.
It is a good thing. Because the content of resin B is low
Conceivable.

[0056] Example 5Toner constituent material Resin A: Polyester resin 85 parts by weight (Tg 60 ° C, no THF insoluble matter) Resin B: Styrene-methyl acrylate 10 parts by weight (Tg63 ° C, Mp10200, Mw / Mn2.9, THF insoluble matter) Release agent: Carnauba wax (mp 82 ° C) 5 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. The result of this toner
The Tg of the resin A having a high proportion in the coating resin is the resin A of Example 4.
Although it is lower than that of Tg, the storage stability is better than that of Example 4.
It was Resin T, which has a high probability of existing on the toner surface, has a high Tg
It is thought that it depends. In addition, even if Tg is high, shear
Low molecular weight distribution, low temperature fixability, gloss and transparency
Clear effect suitable for full-color images.
was gotten.

[0057] Example 6Toner constituent material Resin A: the same resin as Resin A of Example 5 87 parts by weight Resin B: Styrene-methyl acrylate 8 parts by weight (Tg 62 ° C, Mp8000, Mw / Mn3.1, THF insoluble matter) Release agent: ester wax (mp 80 ° C) 5 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. However,
In the evaluation to be used, the fixing device B is used as the fixing device.
The thing which removed the oil application roller was used. Got
The resulting image is glossy and sharp, suitable for full-color images.
Therefore, the transparency was also good. Also, there is no oil application
Even when fixing at low temperature, there is a margin before offset occurs.
It was something.

Comparative Example 1 Resin B of Example 3 was prepared by using a styrene-butyl acrylate copolymer (Tg 60 ° C., Mp6400, Mw / Mn3.6, T).
Toner was evaluated in the same manner as in Example 3 except that the content was changed to HF insoluble matter). The dispersion state of the wax of this toner was a little worse than that of Example 3, but it was a size without any problem. The low-temperature fixability and the offset allowance were also the same as in the case of Example 3. However, the image was slightly low in gloss, particularly low in transparency and insufficient in sharpness.

[0059] Comparative example 2Toner constituent material Resin A: the same resin as the resin A of Example 1 86 parts by weight Resin B ... Hydrogenated petroleum resin 10 parts by weight (Tg82 ° C, Mp1500, Mw / Mn2.1, no THF insoluble matter) Release agent: polyethylene wax (mp 90 ° C) 4 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. Use this toner
When the fixability was evaluated by using the
However, the offset generation temperature was also low. Also durable
In the property evaluation, scumming was confirmed around 9000 sheets.

[0060] Comparative Example 3Toner constituent material Resin A: the same resin as the resin A of Example 1 86 parts by weight Resin B: Styrene-butadiene copolymer 10 parts by weight (Tg74 ° C, Mp13000, Mw / Mn3.2, THF insoluble matter) Release agent: polyethylene wax (mp 90 ° C) 4 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. This toner is
The pulverizability was worse than that of the conventional toner. Suchi
The pulverizability of the len-butadiene copolymer is poor, and
For most other toners with similar wax dispersion diameter
The amount of wax present on the surface is larger than that on the surface.
The liquidity of Na was poor. Obtained using this toner
The image shows uneven density and the developability or transferability is not good.
It was confirmed. The durability test shows that this image quality is poor.
It got worse.

[0061] Comparative Example 4Toner constituent material Resin A: Polyester resin 44 parts by weight (Tg 62 ° C, no THF insoluble matter) Resin B: Styrene-methyl acrylate-methyl methacrylate copolymer (Tg59 C, Mp8200, Mw / Mn4.2, THF insoluble matter)                                               50 parts by weight Release agent: Ester wax (mp 80 ° C) 6 parts by weight Colorant, charge control agent ... Same as in Example 1 The above toner constituent materials are made into toner by the same method as in Example 1.
Then, the same evaluation as in Example 2 was performed. This toner manufacture
The pulverizability at that time is very good, but there are many fine powders,
It could not be removed completely. Styrene-acrylic resin content
It is thought that this is due to the large amount. Because it is easily crushed
In the durability evaluation, the amount of fine powder in the developing section was large.
Scratch on the armpit causes continuous printing around 6000 sheets
did. Also, the dispersed state of the wax is not bad and the Tm is high.
It was not too much, but the transparency was poor.

[0062]

[Table 1]

[0063]

EFFECTS OF THE INVENTION According to the present invention, it has gloss and transparency suitable for full color, has both low-temperature fixing property and hot offset resistance, and contains wax, which is a side effect of deterioration of transferability, deterioration of storage stability, and durability. Suppressed the deterioration of
It has good pulverizability, but since it does not over-mill, it has good production efficiency
A toner having no problem of image quality deterioration due to the fine powder was obtained.

[Brief description of drawings]

FIG. 1 is a schematic diagram of the structure of belt heating and fixing.

FIG. 2 is a schematic view of the structure of roller fixing.

[Explanation of symbols]

R1 fixing roller R2 pressure roller R3 heating roller R4 oil application roller B fixing belt T Unfixed toner image P print sheet S temperature sensor G guide H heating source

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoichiro Watanabe             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Masahide Yamashita             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Kazuto Watanabe             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Mitsuteru Kato             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Maiko Kondo             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh F-term (reference) 2H005 AA01 AA06 AA15 AA21 CA04                       CA08 CA14 EA03 EA06 EA07                 2H033 AA11 BA11 BA58

Claims (4)

[Claims] 1. A resin containing at least resin A, resin B and wax, which are incompatible with each other and have a sea-island phase-separated structure, and which satisfy the following conditions (1) to (5): A full-color toner for electrophotography, which is characterized in that (1) The sea-island phase-separated structure is a structure in which a resin B is dispersed in an island-like resin A that is a continuous phase and the wax is substantially included in the island-shaped resin B. thing. (2) The binder resin in the toner has no THF insoluble content. (3) The resin A is mainly polyester and / or polyol, and the resin B is a copolymer resin of styrene and methyl acrylate and / or methyl methacrylate. (4) The content of resin A, resin B, and wax is resin A>
Resin B ≧ wax. (5) The wax content is 2 to 15% by weight. 2. An electrostatic latent image on a photoconductor is visualized with toner, the obtained toner image is transferred to a transfer medium, and then the toner image is fixed while contacting the toner image with an endless belt or an endless belt. The full-color toner for electrophotography according to claim 1, which is used in an image forming method. 3. The full color toner for electrophotography according to claim 1, wherein the content of the resin B is 20% by weight or less. 4. The glass transition point of the resin B is higher than that of the resin A, the THF-soluble component of the resin B has a peak molecular weight distribution of 5,000 or more by GPC, and the weight average molecular weight and the number average molecular weight are The full-color toner for electrophotography according to claim 1, wherein the ratio is 4 or less.