JP2003287924A - Toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner improved in pulverizing property in the manufacturing stage and improved in fixing strength to a recording medium such as paper while keeping low temperature fixing property and offset resistance. <P>SOLUTION: The toner contains a polymer as a binder resin which is obtained by bulk polymerization of a compound having two or more isocyanate groups and a compound having two or more functional groups having active hydrogen and which has a urethane coupling or urea coupling in the main chain and 1,500 to 20,000 number average molecular weight (Mn) basing on polystyrene as a reference. The compound having two or more functional groups having active hydrogen comprises at least an aliphatic polyol having a branched structure or an aliphatic polyamine having a branched structure. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner used for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing and the like by heat fixing.

[0002]

2. Description of the Related Art As a toner, usually, a releasing agent, a colorant, a charge control agent, etc. are dispersed in a binder resin, and then the particles are pulverized and classified by a finely pulverizing means into toner particles. Depending on the developing method, it is a one-component toner particle or a two-component toner composed of toner particles and carrier particles.

Recently, in electrophotography, further higher speed and lower temperature fixing are required, and it is essential to characterize the binder resin constituting the toner particles at a low temperature. Therefore, JP-A-63-174061 discloses that a binder resin in a toner has a reaction product of a compound having at least one isocyanate group and a monoalcohol and / or at least two hydroxyl groups. It is disclosed that the reaction product of the compound and monoisocyanate is contained, and that the reaction product is a low molecular weight compound having a low melting point, but the low melting point has an effect of lowering the fixing temperature. On the other hand, there is a problem that offset resistance is lowered, durability as a toner is lowered, filming on a transfer roller or the like is likely to occur, and storage stability and blocking resistance are deteriorated.

Further, Japanese Patent Laid-Open No. 63-
Japanese Patent No. 66564 discloses a toner having as a binder a reaction product of a compound having at least one hydroxyl group or amino group and a monoisocyanate compound or a polyisocyanate compound, and the reaction product has a substantially single molecular weight. It is disclosed that the compound is a compound having a molecular weight of 500 or less and a melting point of 50 to 150 ° C. However, although it has the effect of lowering the fixing temperature due to the low melting point as described above, on the contrary, the same as above. Have the problem of.

In order to meet the demand for higher speed and lower temperature fixing, there are internally dispersed toner particles for oilless fixing in which wax is dispersed in a binder resin. For example, in JP-A-9-34170, a binder resin, a colorant and a lubricant are exemplified, and a urethane resin is exemplified as the binder resin, the binder resin has a weight average molecular weight of 50,000 or more, and the melting point of the lubricant is It is disclosed that a toner having excellent low-temperature fixing property, anti-offset property, and anti-blocking property can be obtained by using a specific toner. However, as the internal cohesive force at the time of melting the binder resin decreases due to the addition of wax, it is necessary to prevent offset such as adhesion to the fixing roller, and at present the wax content must be increased. Yes, there is a problem that not only the durability of the toner is deteriorated, but also it is difficult to optimize the dispersion condition of the release agent or the pulverization condition, and by adding more release agent than necessary, When the color toner is used, there is a problem that the transparency is lowered.

Further, a styrene-acrylic copolymer is generally used as a toner binder. For example, Japanese Patent Laid-Open No. 6-27731 discloses a twin-screw extrusion reactor for the polymerization reaction for the purpose of continuous production. However, there is a problem in continuous production because the residual amount of unreacted monomer increases and a removal process is required. Further, even in the case of a polyester resin used as a toner binder like a styrene-acrylic copolymer, it is necessary to take out components such as water from the reaction system in order to control the reaction in the polymerization reaction step. There are problems with productivity.

Further, the present applicant has previously filed Japanese Patent Application No. 2001-2001.
No. 112588, obtained by bulk polymerization of a polyisocyanate and a polyactive hydrogen compound, having a urethane bond or a urea bond in the main chain, and having a number average molecular weight (Mn) of 1,500 to 20, based on polystyrene.
A toner containing 000 polymers as a binder resin has excellent low-temperature fixability and excellent offset resistance and is particularly useful as a color toner. However, a resin having a urethane bond or a urea bond is used. It has been found that the elasticity is high, and there are certain problems in pulverizability during manufacturing and fixing strength of the toner image fixed on the recording medium.

[0008]

SUMMARY OF THE INVENTION The present invention is a toner for improving pulverizability at the manufacturing stage while maintaining low-temperature fixing property and anti-offset property, and improving fixing strength on a recording medium such as paper. Is an issue.

[0009]

The toner of the present invention is obtained by bulk polymerization of a compound containing two or more isocyanate groups and a compound containing two or more functional groups having active hydrogen, and has a urethane bond or a urea bond. A toner containing a polymer having a bond in the main chain and having a number average molecular weight (Mn) of 1,500 to 20,000 based on polystyrene as a binder resin has two functional groups having active hydrogen. The compound contained above is characterized in that it comprises at least an aliphatic polyol having a branched structure or an aliphatic polyamine having a branched structure.

The compound having two or more functional groups having active hydrogen is further represented by the following formula (1)

[0011]

[Chemical 2]

(Wherein R is an ethylene group or a propylene group, which may be the same or different, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 1).
It is 2. ) It is characterized by containing the compound shown by.

The above-mentioned polymer is characterized in that the weight average molecular weight (Mw) / number average molecular weight (Mn) is 1.5 to 20.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Conventionally, as a binder resin for toner, a binder resin composed of a high molecular weight polyester resin is known,
Toner particles are obtained by kneading and finely pulverizing a resin with a colorant and a charge control agent. The binder resin holds the colorant particles and the like in the toner particles, and at the time of fixing, has the function of being softened by the heat and pressure of the fixing roller and adhering the toner particles to the transfer material such as paper. For the purpose of lowering the molecular weight of the binder resin and lowering the softening temperature, the glass transition temperature and the strength are lowered, and the retention of the colorant, the anti-offset property, the strength of the fixed image, and the preservability are lowered. To do.

The resin having a urethane bond or a urea bond is a urethane bond (-A-NHCOO-B-, where A is a polyisocyanate residue, B is a polyactive hydrogen compound residue) formed as a result of the reaction between a hydroxyl group and an isocyanate group. ), Or a urea bond (-NHCONH-) formed as a result of the reaction between an amino group and an isocyanate group, as an binding element, and its intermolecular cohesive energy is 8.74 kcal / m.
and 0.68 kc of methine bond (—CH ₂ —)
al / mol, 1.0 kca of ether bond (-O-)
l / mol, benzene-bonded 3.9 kcal / mol,
It is remarkably large as compared with 2.9 kcal / mol in the ester bond, and its glass transition point is high due to its high crystallinity. However, the number average molecular weight (Mn) of 1,500 to 20,000 based on polystyrene can have a flow softening point of 140 ° C. or lower at a low temperature due to the lowering of the molecular weight. It has excellent fixability, and its glass transition temperature can be 55 ° C. or higher despite its softening point being lowered, and the degree of glass transition temperature and strength reduction are small, and it is colored as a binder resin in toner. Although a binder resin having excellent agent retention, heat resistance, storability, and the like can be obtained, it is required to have a higher fixed image strength.

The resin having a urethane bond or a urea bond can be obtained by bulk polymerization of polyisocyanates and a polyactive hydrogen compound. As the polyisocyanates, ethane diisocyanate, propane diisocyanate, butene diisocyanate, which are aliphatic diisocyanates, butane diisocyanate, thiodiethyl diisocyanate, pentane diisocyanate, β-methylbutane diisocyanate, hexane diisocyanate,
ω, ω′-dipropyl ether diisocyanate, thiodipropyl diisocyanate, heptane diisocyanate, 2,2-dimethylpentane diisocyanate, 3-
Methoxyhexane diisocyanate, octane diisocyanate, 2,2,4-trimethylpentane diisocyanate, nonane diisocyanate, decane diisocyanate, 3-butoxyhexane diisocyanate, 1,4
-Butylene glycol-dipropyl ether-ω, ω '
-Diisocyanate, undecane diisocyanate, dodecane diisocyanate, thiodihexyl diisocyanate and the like.

As the aliphatic diisocyanate having a cyclic group, ω, ω'-1,3-dimethylbenzene diisocyanate, ω, ω'-1,2-dimethylbenzene diisocyanate, ω, ω'-1,2-dimethyl Cyclohexane diisocyanate, ω, ω′-1,4-dimethylcyclohexane diisocyanate, ω, ω′-1,4-
Diethylbenzene diisocyanate, ω, ω′-1,4
-Dimethylnaphthalene diisocyanate, ω, ω'-
1,5-dimethylnaphthalene diisocyanate, 3,5
-Dimer cyclohexane-1-methyl isocyanate-
2-propyl isocyanate, ω, ω′-n-propyl-biphenyl diisocyanate and the like can be mentioned.

1,3 as the aromatic diisocyanates
-Phenylene diisocyanate, 1,4-phenylene diisocyanate, 1-methylbenzene-2,4-diisocyanate, 1-methylbenzene-2,5-diisocyanate, 1-methylbenzene-3,5-diisocyanate, 1,3-dimethylbenzene -2,4-diisocyanate, 1,3-dimethylbenzene-4,6-diisocyanate, 1,4-dimethylbenzene-2,5-diisocyanate, 1-ethylbenzene-2,4-diisocyanate, 1-isopropylbenzene-2, 4-diisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate and the like can be mentioned.

The naphthalene diisocyanates include naphthalene-1,4-diisocyanate and naphthalene-
1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1′-dinaphthyl-2,2′-diisocyanate and the like can be mentioned.

The biphenyl diisocyanates include biphenyl-2,4'-diisocyanate and biphenyl-diisocyanate.
4,4'-diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 2-
Examples thereof include nitrobiphenyl-4,4'-diisocyanate.

Examples of di- or triphenylmethane diisocyanate and di- or triphenylethane diisocyanate include diphenylmethane-4,4'-
Diisocyanate, 2,2'-dimethyldiphenylmethane-4,4'-diisocyanate, diphenyldimethylmethane-4,4'-diisocyanate, 2,5,2 ',
5'-tetramethyldiphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxydiphenylmethane-4,4'-diisocyanate, 4,4'-dimethoxyphenyl-3,3'-diisocyanate, 4,4'-diisocyanate Ethoxyphenylmethane-3,3'-diisocyanate, 2,2'-dimethyl-5,5'-dimethoxydiphenylmethane-4,4'-diisocyanate, 3,3-dichlorodiphenyldimethylmethane-4,4'-diisocyanate, benzophenone -3,3'-diisocyanate, α, β-diphenylethane-2,4-diisocyanate, 3-nitrotriphenylmethane-4,4'-diisocyanate, 4-nitrotriphenylmethane-4,
4'-diisocyanate and the like, or derivatives thereof.

Examples of triisocyanates include 1-methylbenzene-2,4,6-triisocyanate, 1,3
5-trimethylbenzene-2,4,6-triisocyanate, naphthalene-1,3,7-triisocyanate,
Biphenyl-1,3,7-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, 3-
Examples include methyldiphenylmethane-4,6,4'-triisocyanate, triphenylmethane-4,4 ', 4 "-triisocyanate, diphenyl-4,4'-diisocyanatocarbamic acid chloride and the like, and derivatives thereof. It

The polyisocyanate has the following formula

[0024]

[Chemical 3]

(In the formula, R ¹ is a methylene group, an ethylene group,
-C (CH _{3) 2} - represents an alkylene group selected from the group, R ² and R ³ is a group selected alkyl group having 4 or less carbon atoms, an alkoxy group, a halogen. By using the diisocyanates represented by the formula (1), a polymer having excellent pulverizability can be obtained, and productivity in the pulverization step for producing a toner can be improved. Specific examples of the diisocyanate represented by the above formula include diphenylmethane-4,4'-diisocyanate, 2,2'-dimethyldiphenylmethane-4,4'-diisocyanate, 2,2 ', 5,5'-
Tetramethyldiphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxydiphenylmethane-4,
4'-diisocyanate, 2,2'-dimethyl-5,
5'-dimethoxydiphenylmethane-4,4'-diisocyanate, 3,3'-dichlorodiphenylmethane-
4,4'-diisocyanate, α, β-diphenylethane-4,4'-diisocyanate and the like, or derivatives thereof can be mentioned, and it is preferable to use a mixture of these polyisocyanates.

The polyisocyanate represented by the above formula has a structure in which two aromatic rings are bonded through an alkylene group as a basic skeleton, and by using this component as a hard segment, a binder polymer is obtained. It is considered that the pulverizability is excellent because the flexibility of the molecular chain in can be reduced and the structure becomes rigid.

When an alicyclic diisocyanate compound is used as the polyisocyanate, it has excellent light resistance when used as a toner and does not fade when stored for a long time. Since the alicyclic diisocyanate compound has a cycloaliphatic hydrocarbon structure, it is considered that deterioration by light or heat can be suppressed. Further, the binder polymer obtained has a rigid structure and is excellent in pulverizability, and can improve the productivity in the pulverization and classification steps when forming a toner.

The alicyclic diisocyanate compound has a structure in which two isocyanate groups are bonded to a cycloaliphatic hydrocarbon or a polycyclic aliphatic hydrocarbon directly or via an alkylene group.

[0029]

[Chemical 4]

An isophorone diisocyanate represented by:
Further, ω, ω′-1,2-dimethylcyclohexane diisocyanate, ω, ω′-1,4-dimethylcyclohexane diisocyanate, and 3,5-dimercyclohexane-1-methylisocyanate-2-propylisocyanate are exemplified.

The following equation

[0032]

[Chemical 5]

(In the formula, R ¹ is selected from a single bond, a methylene group, an ethylene group and a —C (CH ₃ ) ₂ — group, and l and m
Is an integer of 1 to 5, and n is an integer of 0 to 2. ) Is also preferable, for example, a polycyclic aliphatic diisocyanate represented by the following structural formula

[0034]

[Chemical 6]

An example is norbornane diisocyanate represented by:

In the present invention, diphenylmethane-4,4'-diisocyanate (MDI) and isophorone diisocyanate (IPD) are used from the viewpoints of pulverizability at the time of producing a toner and fixing strength on a recording medium.
I), norbornane diisocyanate (NBDI), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), p-xylylene diisocyanate,
m-xylylene diisocyanate (XDI), p-phenylene diisocyanate, p-tetramethyl xylylene diisocyanate, m-tetramethyl xylylene diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, 1,3-bis (isocyanate) Natomethyl) cyclohexane (hydrogenated XD
I), diisocyanates having alicyclic hydrocarbons such as 2,4-tolylene diisocyanate (TDI) and aromatic hydrocarbons are preferable, and a mixture of these polyisocyanates may be used.

Next, the polyols and polyamines that are reacted with polyisocyanates will be described. The present invention improves the pulverizability in the production stage while maintaining the low-temperature fixability and offset resistance of the urethane resin toner,
Further, for the purpose of improving the fixing strength to a recording medium such as paper, an aliphatic polyol having a branched structure as a bulky component having a low degree of freedom, which disturbs the crystallinity of the urethane resin as a multi-active hydrogen compound, or An aliphatic polyamine having a branched structure is used.

Examples of the aliphatic polyol having a branched structure include 2-ethyl-1,3-hexanediol,
2,2-dimethyl-1,3-propanediol, 1,3
-Butanediol, 2,3-butanediol, 1,2-
Propanediol, 2-methyl-2,4-pentanediol and the like are exemplified, and as the aliphatic polyamine having a branched structure, for example, 2-ethyl-1,3-hexanediamine, 2,2-dimethyl-1 , 3-propanediamine, 1,3-butanediamine, 2,3-butanediamine, 1,2-propanediamine, 2-methyl-2,4-
Pentane diamine etc. are illustrated. The aliphatic polyol having a branched structure and the aliphatic polyamine having a branched structure may have a smaller molecular weight than the compound represented by the above formula (1).

Examples of the polyoxyalkylene bisphenol A ether compound represented by the above formula (1) include ethylene oxide 2 to 12 mol adduct of bisphenol A (hereinafter referred to as EO adduct) and propylene oxide 2 to 12 of bisphenol A. Examples thereof include molar adducts (hereinafter referred to as PO adducts), and these may be used alone or as a mixture of both. Furthermore, EO group or PO
Two or more compounds having different numbers of repeating units may be mixed and used. When both are used as a mixture, the mixing ratio (molar ratio) is EO adduct / PO adduct = 8: 2
It is 1: 9, preferably 8: 2 to 2: 8, and more preferably 7: 3 to 4: 6. Moreover, R may be the same or different, and one may be an ethylene group and the other may be a propylene group. Further, the physical properties of the EO group and the PO group change depending on the number of repeating units when they are used as a binder polymer. x
The average value of + y is 2 to 12, preferably 2 to 4, and if the number of repeating units is larger than this, it is not preferable because it causes a decrease in glass transition temperature and deterioration of pulverizability. Peeling strength decreases. Further, the fixing strength (break-off strength) can be improved by increasing the composition ratio of the EO component, but it lowers the glass transition temperature and deteriorates the pulverizability. On the contrary, increasing the composition ratio of the PO component causes pulverization. However, the fixing strength (break-off strength) is reduced. The hydroxyl value of the polyoxyalkylene bisphenol A ether compound is 100.
~ 350 KOHmg / g, preferably 200-290 K
OH mg / g. By using bisphenol A as a basic skeleton, the polyoxyalkylene bisphenol A ether compound has a small molecular chain flexibility and a rigid structure when used as a binder polymer which is a reaction product with polyisocyanate. Conceivable.

The aliphatic polyol having a branched structure or the polyamine having a branched structure is a polyoxyalkylene bisphenol A ether 1 represented by the above formula (1).
It may be 1 mol to 900 mol, preferably 5 mol to 100 mol, and more preferably 10 mol to 60 mol with respect to 00 mol. As a result, the pulverizability during toner production, low-temperature fixability, offset resistance at high temperatures, and fixing strength are superior, and the required softening point (Tm) and glass transition temperature (Tg) can be adjusted easily. Become.

Further, other polyols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (caprolactone polyol), poly (hexamethylene carbonate) are used as long as the properties of the toner due to the above-mentioned polyactive hydrogen compound are not impaired. ), Bis (2-hydroxyethyl) terephthalate, etc. may be added.

In general, in a resin having a urethane bond or a urea bond, it is considered that a portion having a high density of urethane bonds or urea bonds existing in the polymer chain behaves as a hard segment, and has a microscopic structure. As
It is presumed that the structure has both a crystal structure composed of hard segments in the molecular chain and an amorphous structure composed of soft segments in the molecular chain surrounding the hard segment. In the crystal structure, it is considered that the molecular chains are regularly arranged and the intermolecular distance is short, so that the internal cohesive force becomes strong. In a resin having such a urethane bond or a urea bond, a portion having a high density of urethane bonds or urea bonds in its molecular chain,
By placing a component with a bulky structure that has less freedom to inhibit crystallization, the incomplete aggregation / crystallization state in which the molecular chains are properly aligned without excessively suppressing its aggregation or crystallinity Therefore, it is considered that this may improve the pulverizability during the production of the toner, the offset resistance at high temperature, and the fixing strength.

The reaction ratio between the polyisocyanate and the polyactive hydrogen compound is 0.5 to the ratio of the number of active hydrogen groups in the polyactive hydrogen compound to the number of isocyanate groups in the polyisocyanate {NCO / active hydrogen (equivalent ratio)}.
1.0, preferably in the range of 0.7 to 1.0, temperature 3
Bulk polymerization may be performed at 0 ° C. to 180 ° C., preferably 30 ° C. to 140 ° C. under atmospheric pressure and without solvent for several minutes to several hours. Examples of the catalyst include dibutyltin dichloride, dimethyltin dichloride, tin octylate, triphenylammonium dichloride, triethylamine, N, N-dimethylcyclohexylamine, triethylenediamine, dimethylaminoethanol, dioctyltin dilaurate, dioctyltin dineodecanoate, Examples thereof include dibutyltin bis (mercapto acid ester).

The reaction between the polyisocyanate and the polyactive hydrogen compound can be carried out in the absence of a solvent, a solvent is not required as in the case of solution polymerization, and a by-product is not generated as in a polycondensation reaction, which is efficient. Continuous production is possible.

As the binder resin in the toner of the present invention, a resin having a urethane bond or a urea bond as a main component is used in the range of less than 50% by weight in the binder resin, and the property of the main component is not impaired. Other binder resin may be contained. The other binder resin may be coexistent at the time of producing the binder resin, or may be kneaded after the production. When the binder resin of the present invention is made to coexist during production, a resin containing no reactive group with polyisocyanates is preferable. Examples of other binder resins include polystyrene, poly-α-methylstyrene, chloropolystyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer. , Styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-acrylic acid ester-methacrylic acid ester copolymer, styrene- A styrene resin such as α-chloromethyl acrylate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, etc., a homopolymer or copolymer containing styrene or a styrene substituent, a polyester resin, an epoxy resin, a urethane-modified epoxy resin. , Silicone modified epoxy resin, Vinyl chloride resin, rosin-modified maleic acid resin, phenyl resin, polyethylene, polypropylene, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin, polyvinyl butyral resin, terpene resin, phenol resin, Aliphatic or alicyclic hydrocarbon resins can be used alone or in combination.

The binder resin and toner of the present invention have a number average molecular weight (Mn) of 1,500 to 20,000 when measured by gel permeation (GPC) based on polystyrene.
0, preferably 2,000 to 10,000, more preferably 3,000 to 8,000. When the number average molecular weight (Mn) is less than 1,500, the low-temperature fixability is excellent, but the colorant retention, filming resistance, offset resistance, fixed image strength, and storage stability are poor. If it is more than 20,000, the low-temperature fixability will be poor, and the binder resin cannot be used alone. The weight average molecular weight (Mw) is 3,000 to 30.
50,000, preferably 5,000 to 50,000, more preferably 8,000 to 20,000, and Mw /
Mn is 1.5-20, preferably 1.8-10, more preferably 1.8-8, and most preferably 1.8-5.

To control the molecular weight of the binder resin,
Ratio of the number of active hydrogen groups in the polyactive hydrogen compound to the number of isocyanate groups in the polyisocyanate (NC
O / active hydrogen) can be reduced to lower the molecular weight,
Since the molecular weight can be made higher by approaching the equivalent amount, it can be easily controlled by appropriately controlling the reaction mole number of polyisocyanate. In addition, a chain extender may be appropriately used within a range that does not affect the physical properties of the binder resin of the present invention. Examples of the chain extender include ethylene glycol, propylene glycol, 1,4-butanediol, bis- (β-hydroxy) benzene and trimethylolpropane.

In order to achieve both offset resistance and melting characteristics, the Mw / Mn of the resin is usually increased, that is, the resin is designed to have a broad molecular weight distribution, or a low molecular weight material and a high molecular weight material are used. The method of making and blending separately is taken, but increasing Mw / Mn,
The blended product does not melt sharply, so that the transparency is deteriorated, and in particular, the image quality of a color image is deteriorated. On the other hand, the binder resin of the present invention has a narrow molecular weight distribution, exhibits sharp melting characteristics, is excellent in transparency, and can provide a high-quality color image.

The toner of the present invention has a flow softening point (Tm).
Is in the range of 80 ° C to 150 ° C, preferably 90 ° C to 140 ° C, and more preferably 100 ° C to 130 ° C. When the flow softening point (Tm) is lower than 80 ° C., the filming resistance is poor, and when it is higher than 150 ° C., the low temperature fixing property is poor.

The glass transition temperature (Tg) is 45 ° C.
It is in the range of 100 ° C, preferably 50 ° C to 80 ° C, and more preferably 55 ° C to 75 ° C. Glass transition temperature (T
If g) is lower than 45 ° C, the storage stability will be poor, and if it is higher than 100 ° C, the Tm will increase accordingly, and the low temperature fixability will be poor.

The binder resin in the present invention can reduce the decrease width of Tg when the molecular design is made to lower the molecular weight and lower Tm, and can achieve both low Tm and high Tg. Also, the melt viscosity at the 50% outflow point is 3 ×
It can be 10 ^{3 to} 1.5 × 10 ⁴ Pa · s, and can be suitable as an oilless fixing toner.

The toner of the present invention may contain a colorant, a charge control agent, and if necessary, a release agent, a dispersant, magnetic particles and the like.

As the colorant, various organic or inorganic pigments and dyes of various colors as described below can be used. Examples of black pigments include carbon black, copper oxide, ferrosoferric oxide, manganese dioxide, aniline black and activated carbon. Examples of yellow pigments include yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, bunzer yellow G, bunzer yellow 10G, benzidine yellow G, benzidine yellow GR, There are quinoline yellow rake, permanent yellow NCG and tartrazine rake. Orange pigments include red yellow lead, molybdenum orange, permanent orange GTR,
Examples include pyrazolone orange, vulcan orange, induslen brilliant orange RK, benzidine orange G and induslen brilliant orange GKM. The red pigment, red iron oxide, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, resole red, pyrozolone red, watching red, calcium salt, lake red D, brilliant carmine 6B,
Eosin Rake, Rhodamine Rake B, Alizarin Rake, Brilliant Carmine 3B and others. Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake. As the blue pigment, dark blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partial chlorinated compound,
First Sky Blue, Induslen Blue BC, etc. Examples of green pigments include chrome green, chrome oxide, pigment green B, malachite green lake, and final yellow green G. White pigments include zinc white, titanium oxide, antimony white, and zinc sulfide. Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Various dyes such as basic dyes, acid dyes, dispersion dyes, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

When used as a light-transmitting color toner, various kinds of pigments and dyes of the following colors can be used as the colorant. As a yellow pigment, C.I.
I.10316 (Naphthol Yellow S), CI11710 (Hansa Yellow 10G), CI11660 (Hansa Yellow 5G), CI1167
0 (Hansa Yellow 3G), CI11680 (Hansa Yellow G),
CI11730 (Hanza Yellow GR), CI11735 (Hanza Yellow A), CI11740 (Hanza Yellow NR), CI12710 (Hanza Yellow R), CI12720 (Pigment Yellow L), CI21090 (Benzidine Yellow), CI21095 (Benzidine Yellow G), CI21100 (Benzine Yellow G)
R), CI20040 (Permanent Yellow NCG), CI21220
(Vulcan Fast Yellow 5), CI21135 (Vulcan Fast Yellow R) and others. As the red pigment, C.I.
I.12055 (Stalin I), CI12075 (Permanent Orange), CI12175 (Resor Fast Orange 3G
L), CI12305 (Permanent Orange GTR), CI117
25 (Hansa Yellow 3R), CI21165 (Vulcan Fast Orange GG), CI21110 (Benzidine Orange G),
CI12120 (Permanent Red 4R), CI1270 (Para Red), CI12085 (Fire Red), CI12315
(Brilliant Fast Scarlet), CI12310
(Permanent Red F2R), CI12335 (Permanent Red F4R), CI12440 (Permanent Red FRL),
CI12460 (Permanent Red FRLL), CI12420 (Permanent Red F4RH), CI12450 (Light Fast Red Toner B), CI12490 (Permanent Carmine FB), CI15850 (Brilliant Carmine 6B). Examples of blue pigments include CI74100 (metal-free phthalocyanine blue), CI74160 (phthalocyanine blue), and CI74180 (fast sky blue).

These colorants may be used alone or in combination of two or more, but it is desirable to use 1 to 20 parts by weight, preferably 2 to 10 parts by weight, based on 100 parts by weight of the binder resin. If it is more than 20 parts by weight, the fixability and transparency of the toner will be deteriorated, while if it is less than 1 part by weight, the desired image density may not be obtained.

The charge control agent is not particularly limited as long as it can give positive or negative charge by frictional charging, and various organic or inorganic charge control agents can be used.

Examples of the positive charge control agent include nigrosine base EX (manufactured by Orient Chemical Industry Co., Ltd.), quaternary ammonium salt P-51 (manufactured by Orient Chemical Industry Co., Ltd.),
Nigrosine Bontron N-01 (Orient Chemical Co., Ltd.), Sudan Chief Schwarz BB (Solvent Black 3: Colr Index 26150), Fett Schwarz HB
N (CINO.26150), Brilliant Spirits Schwarz TN (manufactured by Farben-Fabricken Bayer), Savong Schwarz X (manufactured by Farberke Hoechst), alkoxylated amines, alkylamides, molybdic acid chelate pigments and the like. Among them, the quaternary ammonium salt P-51 is preferable.

Examples of negative charge control agents include oil black (Color Index 26150) and oil black B.
Y (Orient Chemical Co., Ltd.), Bontron S-22
(Produced by Orient Chemical Industry Co., Ltd.), salicylic acid metal complex E-81 (produced by Orient Chemical Industry Co., Ltd.), thioindigo pigment, sulfonylamine derivative of copper phthalocyanine,
Spyron Black TRH (Hodogaya Chemical Co., Ltd.), Bontron S-34 (Orient Chemical Co., Ltd.), Nigrosine SO (Orient Chemical Co., Ltd.), Celes Schwarz (R) G (Farben Fabricen Bayer), Chromogen Schwarz ETOO (CINO.14645),
Examples thereof include Azo Oil Black (R) (manufactured by National Aniline Co.). Among them, salicylic acid metal complex E
-81 is preferable.

These charge control agents can be used alone or in combination of two or more kinds. The addition amount of the charge control agent added to the binder resin is 0.001 with respect to 100 parts by weight of the binder resin. To 5 parts by weight, preferably 0.00
It is 1 to 3 parts by weight.

Further, in the toner of the present invention, the resin having a urethane bond or a urea bond has excellent heat-melting property due to its molecular weight range, and the release agent is unnecessary due to its viscoelastic property in the fixing temperature range. If added, binder resin 1
It is about 0 to 3 parts by weight with respect to 00 parts by weight.

Specific examples of the releasing agent include paraffin wax, polyolefin wax, modified wax having an aromatic group, hydrocarbon compound having an alicyclic group, natural wax, and a long-chain hydrocarbon chain having 12 or more carbon atoms. Examples thereof include long-chain carboxylic acids having CH ₃ (CH ₂ ) ₁₁ or CH ₃ (CH ₂ ) ₁₂ or more aliphatic carbon chains], their ester fatty acid metal salts, fatty acid acids, and fatty acid bisacids. Different low softening point compounds may be mixed and used. Specifically, paraffin wax (manufactured by Nippon Oil Co., Ltd.), paraffin wax (manufactured by Nippon Seiro Co., Ltd.), microwax (manufactured by Nippon Oil Co., Ltd.), microcrystalline wax (manufactured by Nippon Seiro Wax Co., Ltd.), hard paraffin wax (manufactured by Nippon Seiro Wax Co., Ltd.), PE-130 (Hoechst), Mitsui High Wax 110P (Mitsui Petrochemical), Mitsui High Wax
220P (Mitsui Petrochemical), Mitsui High Wax 660P (Mitsui Petrochemical), Mitsui High Wax 210P (Mitsui Petrochemical), Mitsui High Wax 320P (Mitsui Petrochemical), Mitsui High Wax 410P (Mitsui Petrochemical) ), Mitsui High Wax 420P (Mitsui Petrochemical), modified wax JC-1141 (Mitsui Petrochemical), modified wax JC-2130 (Mitsui Petrochemical), modified wax JC-4020 (Mitsui Petrochemical), modified Wax JC-1142 (Mitsui Petrochemical), modified wax JC
-5020 (manufactured by Mitsui Petrochemical), beeswax, carnauba wax, montan wax and the like can be mentioned. Examples of fatty acid metal salts include zinc stearate, calcium stearate, magnesium stearate, zinc oleate, zinc palmitate, magnesium palmitate and the like.

Examples of the polyolefin wax include low molecular weight polypropylene, low molecular weight polyethylene, oxidized polypropylene, oxidized polyethylene and the like. Specific examples of the polyolefin wax include, for example, Hoechst Wax PE520 and Hoechst Wax PE1.
30, Hoechst Wax PE190 (Hoechst), Mitsui High Wax 200, Mitsui High Wax 210, Mitsui High Wax 21
Non-oxidizing such as 0M, Mitsui High Wax 220, Mitsui High Wax 220M (Mitsui Petrochemical Industry Co., Ltd.), Sun Wax 131-P, Sun Wax 151-P, Sun Wax 161-P (Sanyo Kasei Co., Ltd.) Type polyethylene wax, Hoec
hst Wax PED121, Hoechst Wax PED153, Hoechst Wax PE
D521, Hoechst Wax PED522, Ceridust 3620, Ceri
dust VP130, Ceridust VP5905, Ceridust VP9615
A, Ceridust TM9610F, Ceridust 3715 (Hoechst), Mitsui High Wax 420M (Mitsui Petrochemical Co., Ltd.), Sun Wax E-300, Sun Wax E-250P
Oxidized polyethylene wax such as (Sanyo Chemical Co., Ltd.), Hoechist Wachs PP230 (Hoechst), Viscole 330-P, Viscole 550-P, Viscole 660P
(Sanyo Kasei Kogyo Co., Ltd.) and other non-oxidizing polypropylene waxes, and Viscole TS-200 (Sanyo Kasei Kogyo Co., Ltd.) and other oxidizing polypropylene waxes. These release agents can be used alone or in combination of two or more kinds. As the releasing agent added as necessary, the softening point (melting point) which is the endothermic main peak value in the DSC endothermic curve measured by "DSC120" manufactured by Seiko Instruments Inc. is 40 to 13.
It is recommended to use one having a temperature of 0 ° C, preferably 50 to 120 ° C.

The toner mother particles in the present invention are obtained by kneading and melting the composition obtained above and then pulverizing and classifying with a fine pulverizing means. In order to improve the fluidity,
A fluidity improver may be added externally.

As the fluidity improver, organic fine powder or inorganic fine powder can be used. For example, fluorine-based resin powder, that is, vinylidene fluoride fine powder, polytetrafluoroethylene fine powder, acrylic resin-based fine powder, or the like; or fatty acid metal salt, that is, zinc stearate, calcium stearate, lead stearate, or the like; or metal oxide. That is, iron oxide, aluminum oxide, titanium oxide, zinc oxide, or the like; or fine powder silica, that is, wet process silica, dry process silica, and the silica is surface-treated with a silane coupling agent, a titanium coupling agent, silicon oil, or the like. Treated silica, etc.,
These are used alone or in a mixture of two or more.

A preferable fluidity improver is a fine powder produced by a vapor phase oxidation method of a silicon halogen compound, which is so-called dry process silica or fumed silica, and produced by a conventionally known technique. Is. For example, the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxyhydrogen flame is utilized, and the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl Further, in this manufacturing process, by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound, a fine powder of a composite of silica and another metal oxide is obtained. It is possible to obtain the body, and it includes them. The particle size is 0.001 to an average primary particle size.
It is desirable that it is within a range of 2 μm, and particularly preferably,
It is preferable to use fine silica powder in the range of 0.002 to 0.2 μm. Examples of commercially available silica fine powders produced by the vapor phase oxidation method of a silicon halogen compound used in the present invention include those commercially available under the following trade names. "AEROSIL 130" manufactured by Nippon Aerosil Co., Ltd., 200, 300, 380, TT600, MOX170, MOX80, C
OK84 and the like, and "Ca-OS" manufactured by CABOT Co.
iL M-5 ", the same as MS-7, MS-75, HS-5, EH-5
, WACKER-CHEMIE GMBH's "Wac
ker HDK N 20 V15 ", the following N20E, T30, T40, Dow Corning Co.'s" DC Fine Silica ", Fransil
The company's "Fransol" etc. are mentioned.

Further, it is more preferable to use a treated silica fine powder obtained by subjecting the silica fine powder produced by vapor-phase oxidation of the silicon halogen compound to a hydrophobic treatment. Among the treated silica fine powders, those obtained by treating the silica fine powder so that the degree of hydrophobicity measured by the methanol titration test is in the range of 30 to 80 are particularly preferable. As a method of hydrophobizing, it is imparted by reacting with silica fine powder or chemically treating with an organic silicon compound which physically adsorbs. As a preferred method, the silica fine powder produced by the above vapor phase oxidation of a silicon halogen compound is treated with an organosilicon compound.

Examples of such organosilicon compounds are hexamethylenedisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, Benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethyl Ethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisi Rhoxane, 1,3-diphenyltetramethyldisiloxane and 2 to 12 siloxane units per molecule, one for each terminally located unit
For example, there is dimethyl polysiloxane having a hydroxyl group bonded to Si for individual pieces. These are used alone or as a mixture of two or more.

The particle diameter of the treated silica fine powder is 0.
It is preferable to use those having a range of 003 to 0.1 μm and 0.005 to 0.05 μm. Commercially available products include Taranox-500 (Tarco) and AEROSIL R-972 (Japan Aerosil).

The fluidity improver is added in an amount of 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the toner mother particles. If it is less than 0.01 part by weight, the fluidity is not improved, and if it exceeds 5 parts by weight, fog and bleeding of characters and scattering in the machine are promoted.

As described above, the toner manufacturing method of the present invention basically comprises the following steps. (1) Uniform mixing step of raw materials A predetermined amount of binder resin, colorant, charge control agent, and other additives are added.
The mixture is put into a mixer such as Henschel Mixer 20B (Mitsui Mining Co., Ltd.) and mixed uniformly. (2) Dispersion and Immobilization Step of Each Additive in Binder Resin After uniformly mixing, the mixture was melt-kneaded using a twin-screw kneading extruder (PCM-30 manufactured by Ikegai Kasei Co., Ltd.) to obtain a binder resin. Each additive is dispersed and fixed therein. As the melt-kneading means, there are other batch-type kneaders such as "TEM-37" (Toshiba Machinery Co., Ltd.) and "KRC Kneader" (Kurimoto Iron Works Co., Ltd.) and heating / pressurizing kneaders. A kneader or the like can be used. (3) Crushing step After coarsely crushing the kneaded product to adjust the particle size, a jet crusher "200AFG" (Hosokawa Micron Co., Ltd.) or "IDS-2" (Japan Pneumatic Mfg. Co., Ltd.) is used to jet. Finely pulverized by collision pulverization with air to have an average particle size of 1 to 8 μm. Other examples of the crushing means include a mechanical crusher turbo mill (Kawasaki Heavy Industries, Ltd.) and a super rotor (Nissin Engineering Co., Ltd.). (4) Classifying process For the purpose of removing fine powder and sharpening the particle size distribution, the particle size adjustment by wind power or rotor rotation is performed by the wind power classifier "1.
00ATP "(Hosokawa Micron Corporation) or" DSX
-2 "(Nippon Pneumatic Mfg. Co., Ltd.) or" Elbow Jet "(Nittetsu Mining Co., Ltd.). (5) External Addition Treatment Step A predetermined amount of the obtained colored resin particles and the fluidizing agent are put into a Henschel mixer 20B (Mitsui Mining Co., Ltd.) and uniformly mixed to obtain a toner.

The toner thus obtained has an average particle size of 3 to 10 μm, preferably 5 to 8 μm, which enables high definition. Further, for example, the circularity may be adjusted to 0.93 to 0.99, preferably 0.94 to 0.98 by hot air treatment or the like, and the fluidity and the cleaning property may be excellent.

Next, a fixing device to which the toner of the present invention is applied will be described with reference to FIG. In the figure, 1 is a fixing roller, 2 is a backup roller, 3 is a separation claw, and 4 is a recording medium such as paper.

The fixing roller 1 may be either a single layer type or a multilayer type. In the case of the single layer type, 0.1 to 20 is provided on the peripheral surface of a core metal having a diameter of 15 to 50 mm with a built-in heating means.
mm, preferably 0.5-3 mm thick silicone rubber layer,
Alternatively, it is a laminate of fluororubber layers. Further, in the case of the multi-layer type, it has a built-in heating means and is 15 to 50 mm.
0.1 to 20 mm, preferably 0.5 on the circumference of the core metal
An elastic layer having a thickness of ˜3 mm and a coat layer having a thickness of 0.05 to 2 mm, preferably 0.1 to 1 mm, which are sequentially laminated, and examples of the combination of the elastic layer and the coat layer include (1) an elastic layer made of a silicone resin. A coating layer made of fluororesin, (2) an elastic layer made of silicon rubber, a coating layer made of fluororubber, (3) an elastic layer made of silicon rubber, a coating layer made of silicon rubber and fluororubber And the like. The rubber layer of the single-layer type and the elastic layer of the multi-layer type have a rubber hardness of 30 degrees or less, preferably 15 degrees or less in JISA hardness.

The backup roller 2 may be either a single layer type or a multilayer type. For the single layer type, 0.1 to 20 mm on the peripheral surface of the core metal with a diameter of 15 to 50 mm,
Preferably, a 0.5 to 3 mm thick silicone rubber layer or a fluororubber layer is laminated. Also, in the case of the multi-layer type, the peripheral surface of the core metal having a diameter of 15 to 50 mm has a thickness of 0.1 to 2
0 mm, preferably 0.5-3 mm thick elastic layer, 0.0
A coating layer having a thickness of 5 to 2 mm, preferably 0.1 to 1 mm is sequentially laminated, and the combination of the elastic layer and the coating layer is, for example, (1) an elastic layer made of silicon sponge, and made of highly releasable silicon. Coat layers sequentially laminated, (2) Silicon rubber elastic layer, fluororubber coat layer sequentially laminated, (3) Silicon rubber elastic layer, fluororubber latex, fluororesin coat Layers laminated in sequence, (4)
Elastic layer made of silicone sponge rubber, fluororesin (P
FA tubes) include those in which coating layers are sequentially laminated. The rubber layer of the single-layer type and the elastic layer of the multi-layer type have a rubber hardness of 30 degrees or less, preferably 15 degrees or less in JISA hardness.

The pressing force (linear pressure) between the fixing roller 1 and the backup roller 2 is 0.2 to 2 kgf / cm, preferably 0.3 to 1 kgf / cm, and the nip width is 1 to 20.
mm, preferably 4 to 10 mm. The speed is set appropriately, but the nip passage time is 10 to 150 mse.
c, preferably 30 to 100 msec. At least one of the fixing roller and the backup roller may be a belt fixing device.

[0077]

EXAMPLES The present invention will be described below with reference to examples. Various evaluation methods described in the specification and examples are as follows.

(1) Softening point (Tm) The softening point (Tm) is measured under the following conditions using a "constant load extrusion type thin tube rheometer flow tester CFT-500D" manufactured by Shimadzu Corporation.

Preparation of measurement sample: As a measurement sample, about 1 g of toner was compression-molded to obtain a columnar sample in conformity with the inner diameter of the cylinder of the flow tester.

Measurement conditions Load: 20 Kgf, die hole: 1 mm, die length: 1 mm Measurement method: 1/2 method (2) Fixability measurement method "Color Laser Printer KL-20" manufactured by Konica Corporation.
10 "was used to image. However, for the fixing operation, the fixing device (fixing unit) consisting of a heat roller is removed from the printer, and it can be driven independently by an external drive device.
A fixing device modified so that the fixing nip time can be adjusted was used. The surface temperature of the roller (fixing roller) on the side in contact with the toner image on the paper was modified so that it could be controlled from 100 ° C to 200 ° C.

The application means for applying silicone oil to the surface of the fixing roller is removed, 1,000 unprinted A4 size blank sheets are passed, and the surface of the fixing roller is cleaned with isopropyl alcohol.
Silicone oil was removed from the roller surface. After that, each time the fixing property evaluation image was passed through the fixing device, the surface of the fixing roller was cleaned with isopropyl alcohol and further wiped with a cotton cloth to keep the fixing roller surface free of silicone oil.

An image for fixing property evaluation was fixed under the conditions of a nip width of 8 mm and a passage time of 50 msec using a fixing device in which silicone oil was removed from the surface of the fixing roller.

The fixing evaluation image is a so-called solid image in which toner is evenly attached to a 20 mm square area at a position 10 mm from the front end of the paper (PPC paper "P paper" manufactured by Fuji Xerox Office Supply Co., Ltd.). Yes, the toner adhesion amount was adjusted to 0.4 mg / cm ² .

Non-offset area While the surface temperature of the fixing roller is changed stepwise, the unfixed image sample is passed through the sheet, and the image or a part of the image is transferred to the fixing roller at the time of passing the sheet, and then is transferred to the succeeding sheet. It was visually determined whether or not the transition had occurred. The temperature range in which the offset did not occur was determined by setting the one having the transition to paper with the offset and the one without the offset.

Good fixing strength area After confirming the above-mentioned non-offset area, the fixed image of the fixed sample is erased (sandbox eraser "LI
ON 261-11 ") was rubbed 5 times with a pressing load of 1 Kgf, and the residual ratio of the image density was measured by X-Rite Inc." X ".
-Rite model 404 ". The temperature range in which the image density residual rate was 70% or more was defined as the good fixing strength range. (3) Measurement of molecular weight distribution Toner (5 mg) was dissolved in 5 g of THF, and in order to remove THF-insoluble matters other than resin components and contaminants, G was passed through a membrane filter having a pore size of 0.2 μm
A sample for PC was prepared. The sample thus prepared is measured using GPC under the following conditions. Column: Showa Denko KK-made "Shodex (GPC) KF806M + KF802.5" Column temperature: 30 ° C. Solvent: THF (tetrahydrofuran) Flow rate: 1.0 ml / min. Detector: UV detector (detection wavelength 254 nm) Standard sample: Monodisperse polystyrene standard sample (weight average molecular weight 580 to 3.9 million) (4) Glass transition point (Tg) 10 mg of toner is packed in an aluminum cell,
The measurement is performed under the following conditions using "DSC120" manufactured by Seiko Instruments Inc. Measurement temperature: 0 to 200 ° C. Temperature rising rate: 10 ° C./min Tg: Read from the DSC curve during the second temperature increase. (5) "Particle size" means "average particle size", and "Multisizer type III" (manufactured by Beckman Coulter, Inc.) is used to measure the relative weight distribution by particle size with an aperture tube of 100 μm. Ask. The particle size of the external additive such as silica particles was determined by electron microscopy.

(Example 1) Diphenylmethane-4,4 '
-As a diisocyanate and an isocyanate component,
Polyoxyethylene bisphenol A ether (manufactured by NOF CORPORATION, Uniol DA-400: OH group value 273K)
OHmg / g) / 2,2-dimethyl-1,3-propanediol = 64.5 / 35.5 (molar ratio)
It melt | dissolved by heating at 20 degreeC and it was set as the polyol component.

Isocyanate component / polyol component = 1
/1.15 (equivalent ratio) and mixed as a catalyst dioctyl tin laurate (Neostan U-81 manufactured by Nitto Kasei Co., Ltd.).
0 ") was added at 20 ppm, mixed under heating at 120 ° C., immediately poured into a 200 mm × 300 mm tray, charged into an atmospheric furnace, and held at 120 ° C. for 1 hour, and then at 130 ° C. for 5 hours. Hold the time to complete the reaction,
A polyurethane resin was obtained.

The obtained polyurethane resin had a weight average molecular weight (Mw) of 1.82 × 10 ⁴ and a number average molecular weight (Mw).
n) is 0.72 × 10 ⁴ , Mw / Mn = 2.5,
The Tg was 76 ° C and the Tm was 120 ° C. -The obtained polyurethane resin--93.0 parts by weight-Cyan pigment (CI Pigment Blue 15: 3) -6.0 parts by weight-Charge control agent (Orient Chemical Co., Ltd. "BONTRON E-84"・ ・ ・ ・ 1.0 part by weight was kneaded using a twin-screw kneader, cooled, and then pulverized by a hammer mill and a jet mill, and the volume average particle size after classification was 8.5 μm, which was excellent in pulverizability. Was fine.

To 100 parts by weight of the obtained toner mother particles, 1.0 part by weight of hydrophobic silica (particle size 20 nm) was added and mixed and stirred using a Henschel mixer to obtain a blue toner.

When the fixing property of the obtained toner was evaluated, the non-offset range of 120 to 180 ° C.
The good fixing strength range was 140 to 180 ° C. The fixing strength of the obtained fixed image was 87%.

Example 2 A polyurethane resin was obtained by polymerizing under the same conditions as in Example 1 except that no catalyst was used.

The obtained polyurethane resin had a weight average molecular weight (Mw) of 1.83 × 10 ⁴ , and a number average molecular weight (Mw).
n) is 0.73 × 10 ⁴ , Mw / Mn = 2.5,
The Tg was 76 ° C and the Tm was 119 ° C.

Using the obtained polyurethane resin, a blue toner was prepared in the same manner as in Example 1, and the fixing property of the obtained toner was evaluated.
The temperature was 180 ° C. and the fixing strength was in a good range of 140 to 180 ° C.
The fixing strength of the obtained fixed image was 89%.

Example 3 Polyurethane resin obtained in Example 2 93.0 parts by weight Cyan pigment (CI pigment blue 15: 3) 6.0 parts by weight Charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) 1.0 part by weight Purified carnauba wax 1.0 part by weight was kneaded using a twin-screw kneader, and after cooling, a hammer mill and further It was pulverized by a jet mill, and the volume average particle size after classification was 7.5 μm, and there was no problem in pulverization.

To 100 parts by weight of the obtained toner mother particles, 1.0 part by weight of hydrophobic silica (particle size 20 nm) was added and mixed and stirred using a Henschel mixer to obtain a blue toner.

When the fixing property of the obtained toner was evaluated, the non-offset range of 120 to 190 ° C.
The good fixing strength range was 140 to 190 ° C. The fixing strength of the obtained fixed image was 92%.

Examples 4 to 8 Diphenylmethane-4,4'-diisocyanate (MDI) in Example 1,
Polyoxyethylene bisphenol A ether (DA4
00) in the use amount (mol) shown in Table 1 below,
As the aliphatic hydrocarbon compound having a branched chain, the compounds shown in Table 1 were used in the same amounts (moles) as in Example 1, and the pigment and the charge control agent (C
CA) was used in the addition amount shown in Table 1 below (parts by weight based on 93.0 parts by weight of the obtained polyurethane resin).
A toner was prepared in the same manner.

[0098]

[Table 1]

The characteristics of the toner of each of the examples obtained above were measured in the same manner as in Example 1, and the results are shown in Table 2 below.

[0100]

[Table 2]

(Comparative Example 1) Diphenylmethane-4,4 '
-Diisocyanate / polyoxyethylene bisphenol A ether (Uniol DA-40 manufactured by NOF CORPORATION)
0: OH group number 273 KOH mg / g) = 1 / 1.1 (molar ratio), and the mixture was dissolved by heating at 120 ° C.
Pour into a 0 mm x 300 mm tray, put in an atmospheric furnace, hold at 120 ° C for 1 hour, and then at 130 ° C for 5 hours.
The reaction was completed by holding for a period of time to obtain a polyurethane resin.

The obtained polyurethane resin has a weight average molecular weight (Mw) of 2.23 × 10 ⁴ , and a number average molecular weight (M
n) is 0.89 × 10 ⁴ , Mw / Mn = 2.5,
The Tg was 64 ° C and the Tm was 118 ° C.

Using the obtained polyurethane resin, a toner was prepared in the same manner as in Example 1. The volume average particle size after classification is 12.1 μm, the amount of treatment per unit time in the jet mill during pulverization is about half that of Example 1, and the toner adherence in the mill is large. There was a problem that it was difficult to clean the mill.

When the fixing property of the obtained toner was evaluated, the non-offset range was 120 to 190 ° C., but the good fixing strength range was 170 to 190 ° C., which was insufficient.

[0105]

INDUSTRIAL APPLICABILITY The toner of the present invention can maintain low-temperature fixability and anti-offset property, and can improve pulverizability in the production stage and fixing strength to a recording medium.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a fixing device used in the present invention.

[Explanation of symbols]

1 is a fixing roller, 2 is a backup roller, 3 is a separating claw, and 4 is a recording medium such as paper.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Mikito Nakajima             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation (72) Inventor Kanji Katagiri             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation F-term (reference) 2H005 AA01 AB02 CA15 EA06                 4J034 BA02 BA05 BA06 CA04 CA15                       CB03 CB08 CC02 CC12 CC67                       CD04 HA01 HC01 HC12 HC22                       HC64 JA01 QA05 QA07 QC10                       RA07 RA14

Claims (3)

[Claims] 1. A polystyrene obtained by bulk polymerization of a compound containing two or more isocyanate groups and a compound containing two or more functional groups having active hydrogen, having a urethane bond or a urea bond in the main chain, The number average molecular weight (Mn) of the standard is 1,500 to 20,000.
In a toner containing the polymer of as a binder resin,
A compound containing two or more functional groups having active hydrogen is
A toner comprising at least an aliphatic polyol having a branched structure or an aliphatic polyamine having a branched structure. 2. A compound having two or more functional groups having active hydrogen, which is further represented by the following formula (1): (In the formula, R is an ethylene group or a propylene group, which may be the same or different, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 12.)
A compound represented by the formula (1) is contained.
The toner described. 3. The weight average molecular weight (M
The toner according to claim 1 or 2, wherein w) / number average molecular weight (Mn) is 1.5 to 20.