JP2003231744A - Catalyst for production of polyester for use in toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst for production of a polyester for use in a toner showing such a steep rise in a charge as to resist to fogging, to provide a polyester resin composition containing the catalyst, and to provide the toner containing the polyester resin composition. <P>SOLUTION: The catalyst is provided for the production of the toner comprising an inorganic tin (II) compound, the polyester resin composition comprising the polyester and the catalyst, and the toner containing the polyester composition. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention contains a catalyst for producing a polyester for a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like, and the catalyst. The present invention relates to a polyester resin composition and a toner containing the polyester resin composition.

[0002]

2. Description of the Related Art In recent years, it has been demanded to improve the charge rising property of a two-component toner mainly from the viewpoint of increasing the speed of a copying machine and the non-magnetic one-component toner from the viewpoint of downsizing. Therefore, improvement of various charge control agents has been studied, and for example, many organotin (IV) compounds have been reported in Patent Document 1, Patent Document 2, Patent Document 3, and the like. However, even if such an organic tin compound is used, a sufficient charge rising property is not obtained and fog is observed, so further improvement is desired.

On the other hand, as a catalyst in the production of polyester used as a binder resin for toner, an organic tin (IV) compound such as dibutyltin oxide, a titanium compound such as tetra-n-butyl titanate and a germanium compound such as germanium oxide are used. However, manganese compounds such as manganese oxide are used, but the effect of these catalysts on the chargeability of toner has not been sufficiently studied.

[0004]

[Patent Document 1] JP-A-63-101856 (claim 1)

[Patent Document 2] Japanese Patent Laid-Open No. 61-272758 (Claim 1)

[Patent Document 3] Japanese Patent Laid-Open No. 62-287260 (claim 1)

[0005]

DISCLOSURE OF THE INVENTION The present invention comprises a catalyst for producing polyester which is used in a toner having excellent charge rising property and less likely to cause fogging, a polyester resin composition containing the catalyst, and the polyester resin composition. The purpose of the present invention is to provide the toner.

[0006]

Means for Solving the Problems The inventors of the present invention have considered that the catalyst used in the production of polyester for toner may have an influence on the charge build-up property of polyester, and as a result of investigation, The present invention has been completed.

The present invention relates to (1) a catalyst for producing a polyester for a toner, which comprises an inorganic tin (II) compound, (2) the inorganic tin (II) compound is a tin compound having a Sn--O bond, (3) An inorganic tin (II) compound is a carboxylate tin (II) having a carboxylic acid group having 2 to 28 carbon atoms, a dialkoxy tin (II) having an alkoxy group having 2 to 28 carbon atoms, and oxidation. The catalyst according to (1) or (2), which is at least one selected from the group consisting of tin (II), (4) the polyester, and the catalyst according to any one of (1) to (3) above. (5) The polyester resin composition as described above, wherein the polyester is a resin obtained by using a dihydric or higher valent secondary alcohol and / or a divalent or higher valent aromatic carboxylic acid compound as at least a raw material monomer. Of polyester Fat composition, and (6) above (4) or (5) a toner comprising a polyester resin composition.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a completely new finding that an inorganic tin (II) compound which functions as a catalyst for polyester production is very effective in improving the charge rising property required for toner polyester. It has a feature in the point found. In the present invention, the inorganic tin compound means S
It refers to a tin compound having no n-C bond.

Although the mechanism by which such a remarkable effect is exhibited by the inorganic tin (II) compound is unknown, the inorganic tin (II) compound
Inorganic tin (II), which is greatly affected by deviation of electron density between bonds of Sn (tin) and O (oxygen), halogen atom, etc. which the compound has, and by further improving compatibility with polyester
It is presumed that the uniform dispersion of the particles has further improved the charge rising property.

The inorganic tin (II) compound is preferably a compound having a Sn--O bond, a compound having a Sn--X (X represents a halogen atom) bond, and the like, and more preferably a compound having a Sn--O bond.

As the compound having a Sn--O bond,
Tin (II) oxalate, tin (II) diacetate, tin dioctoate (I
I), tin (II) dilaurate, tin distearate (I
I), tin (II) dioleate, etc., having 2 to 28 carbon atoms
Tin (II) carboxylate having a boric acid group; Dioctyloxy
Tin (II), dilauroxy tin (II), distearoxy tin
(II), dioleyloxy tin (II), etc., having 2 to 28 carbon atoms
Dialkoxy tin (II) having an alkoxy group; tin oxide
(II); tin (II) sulfate or the like is Sn--X (X is a halogen source)
As a compound having a bond (indicating a child), tin chloride (I
I), tin (II) halides such as tin (II) bromide, etc.
Among them, among these, the charge rising effect and the catalytic ability
From the point, (R¹COO)₂Sn (where R¹Has 5 carbon atoms
~ 19 alkyl or alkenyl groups)
Fatty acid tin (II), (R²O)₂Sn (where R ²Is charcoal
Indicating an alkyl group or an alkenyl group having a prime number of 6 to 20)
Dialkoxy tin (II) represented and acid represented by SnO
Tin (II) oxide is preferable, and (R¹COO)₂Represented by Sn
More preferred are fatty acid tin (II) and tin (II) oxide.
Tin (II) octoate, Tin (II) distearate and oxidation
Tin (II) is particularly preferred.

In the catalyst for producing polyester of the present invention, a conventionally known organic tin compound such as dibutyltin oxide may be appropriately used in combination as long as the effect of the present invention is not impaired.

The polyester resin composition containing the catalyst for producing polyester of the present invention and the polyester can be used as a binder resin for toner, and the polyester can be obtained by producing in the presence of such catalyst.

In the production of polyester, an alcohol component composed of a divalent or higher polyhydric alcohol and a carboxylic acid component composed of a divalent or higher polycarboxylic acid compound are mainly used as raw material monomers. A small amount of monohydric alcohol and monocarboxylic acid compound may be appropriately used from the viewpoint of adjusting the molecular weight and improving the offset resistance.

Examples of the divalent polyhydric alcohol include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.2).
Alkylene (C2-4) oxide adduct of bisphenol A such as -2,2-bis (4-hydroxyphenyl) propane (average number of moles added 1.5-6), ethylene glycol, propylene glycol, neopentyl glycol , 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol and the like.

Examples of the trihydric or higher polyhydric alcohols include sorbitol, pentaerythritol, glycerol and trimethylolpropane.

Examples of the divalent carboxylic acid compound include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid and isophthalic acid, sebacic acid, fumaric acid, maleic acid, adipic acid,
Aliphatic dicarboxylic acids such as azelaic acid, dodecenyl succinic acid, dodecyl succinic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and anhydrides of these acids, and derivatives such as alkyl (C 1 to C 3) esters .

Examples of trivalent or higher polyvalent carboxylic acid compounds include aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid and pyromellitic acid. And derivatives of such acid anhydrides and alkyl (C1 to C3) esters.

In the present invention, among the above-mentioned raw material monomers, a dihydric or higher valent secondary alcohol and / or a divalent or higher valent aromatic carboxylic acid compound is preferable. Examples of the dihydric or higher secondary alcohol include propylene oxide adducts of bisphenol A, propylene glycol, 1,3-butanediol, glycerol and the like. Among these, propylene oxide adducts of bisphenol A are preferable and dihydric alcohols are preferable. As the above aromatic carboxylic acid compounds, terephthalic acid, isophthalic acid, phthalic acid and trimellitic acid are preferable, and terephthalic acid and trimellitic acid are more preferable.

The content of the dihydric or higher secondary alcohol and the aromatic carboxylic acid compound, when either one is contained, is preferably 50 to 100 mol% in the alcohol component or the carboxylic acid component, and more preferably 80-100
When both of them are contained, they are preferably 20 to 100 mol%, and more preferably 50 to 100 mol% in all the raw material monomers. The use of either one of the secondary alcohol and the aromatic carboxylic acid compound is preferable, but it is more preferable that both are used in combination. In addition,
In the present invention, the dihydric or higher alcohol is a dihydric or higher alcohol in which at least one hydroxyl group is bonded to the secondary carbon.

In particular, when a propylene oxide adduct of bisphenol A and terephthalic acid are used in combination, due to the resonance effect of the benzene ring contained in both compounds,
It is preferable because the electric charges can be stably present. However, even if two kinds of resins obtained by using any one of them as a raw material monomer are mixed, such an effect by the combined use of both can be obtained.

The polyester may be used in the presence of the catalyst of the present invention,
It can be produced by polycondensing an alcohol component and a carboxylic acid component in an inert gas atmosphere at a temperature of 180 to 250 ° C., if necessary under reduced pressure.

Inorganic tin (II) in the production of polyester
The amount of the compound used is 100 as a raw material monomer for polyester.
0.001 to 5 parts by weight is preferable with respect to parts by weight,
0.05 to 2 parts by weight is more preferable. Therefore, the content of the inorganic tin (II) compound in the polyester resin composition of the present invention obtained by using the inorganic tin (II) compound as a catalyst is also
0.001 to 5 parts by weight is preferable, and 0.05 to 2 parts by weight is more preferable, relative to 100 parts by weight of polyester.

The softening point of polyester is 90 to 170 ° C.
Are preferable, and 95-150 degreeC is more preferable. Further, the glass transition point is preferably 50 to 130 ° C., and 50 to 80 ° C.
C is more preferred.

The polyester content in the polyester resin composition is preferably 50 to 100% by weight, and 80 to 1
00 wt% is more preferable, and 100 wt% is particularly preferable.

Examples of the resin that may be blended with the polyester include addition polymerization resins such as styrene-acrylic resin, epoxy resin, polycarbonate, polyurethane and the like.

The polyester may be contained in the polyester resin composition by mixing with another resin, but when used in combination with another resin, two or more resin components are partially chemically mixed. It is preferably contained as one of the resin components in the combined hybrid resin. That is, the polyester resin composition of the present invention may be composed of a hybrid resin in which the polyester component obtained by using the catalyst of the present invention and the addition polymerization resin component are partially chemically bonded. It should be noted that the hybrid resin may be one obtained from two or more kinds of resins as a raw material, one obtained from a raw material monomer of one kind of resin and another kind of resin, or two or more kinds of hybrid resins. It may be one obtained from a mixture of resin raw material monomers, but one obtained from a mixture of two or more resin raw material monomers is preferable in order to efficiently obtain a hybrid resin.

The softening point of the polyester resin composition is 90.
-170 degreeC is preferable and 95-150 degreeC is more preferable. The glass transition point is preferably 50 to 130 ° C, more preferably 50 to 80 ° C.

Further, the present invention provides a toner containing the polyester resin composition of the present invention as a binder resin.

In the toner of the present invention, in addition to the polyester resin composition, a colorant, a charge control agent, a release agent,
Additives such as a fluidity improver, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, an antiaging agent, and a cleaning property improver may be appropriately blended.

As the colorant, all the dyes and pigments used as the colorant for toner can be used. Carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine- B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow, and the like. These can be used alone or in combination of two or more, and in the present invention, the toner is black. It may be toner, color toner, or full-color toner. The content of the colorant is preferably 1 to 40 parts by weight, more preferably 3 to 10 parts by weight, based on 100 parts by weight of the binder resin.

As the charge control agent, nigrosine dye, 3
-Charged charge control agents such as triphenylmethane dyes containing a quaternary amine as a side chain, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives and metal-containing azo dyes, copper phthalocyanine dyes, metal complexes of alkyl derivatives of salicylic acid And a negatively chargeable charge control agent such as a boron complex of benzylic acid. The toner of the present invention may have either a positive charging property or a negative charging property, and a positive charging control agent and a negative charging control agent may be used in combination.

Examples of the releasing agent include natural ester waxes such as carnauba wax and rice wax, synthetic waxes such as polypropylene wax, polyethylene wax and Fischer Tropsch, coal waxes such as montan wax, and waxes such as alcohol wax. These may be contained alone or in combination of two or more.

The method for producing the toner of the present invention may be any conventionally known method such as a kneading and pulverizing method and an emulsion phase inversion method. For example, in the case of a pulverized toner by the kneading and pulverizing method, a binder resin is used. , A colorant and the like are uniformly mixed with a mixer such as a Henschel mixer or a ball mill, and then melt-kneaded with a closed kneader or a single-screw or twin-screw extruder and the like, followed by cooling, pulverizing and classifying. In the emulsion phase inversion method, the binder resin, the colorant and the like are dissolved or dispersed in an organic solvent, and then water is added to form an emulsion, which is then separated and classified for production. The volume average particle diameter of the toner is
3 to 15 μm is preferable. On the surface of the toner,
A fluidity improver such as hydrophobic silica may be added as an external additive.

The toner of the present invention is used alone as a developer when it contains magnetic fine powder, as a non-magnetic one-component developer when it does not contain magnetic fine powder, or as a mixture with a carrier. It can be used as a component-based developer.

[0036]

[Example] [Softening point] Enhanced flow tester "CFT-"
500D "(manufactured by Shimadzu Corporation), while heating 1 g of the sample at a temperature rising rate of 6 ° C./min, a load of 1.96 MPa is applied by a plunger to obtain a diameter of 1 mm and a length of 1 m.
The nozzle of m is pushed out to draw the plunger drop amount (flow value) -temperature curve of the flow tester, and when the height of the S-shaped curve is h, the temperature corresponding to h / 2 (half of the resin) Is the softening point.

[Glass Transition Point] Differential Scanning Calorimeter “DSC
210 "(manufactured by Seiko Denshi Kogyo Co., Ltd.) was used to raise the temperature to 200 ° C., and the temperature of the sample cooled to 0 ° C. at the temperature decreasing rate of 10 ° C./minute was measured at the temperature increasing rate of 10 ° C./minute. The glass transition point is defined as the temperature at the intersection of the extension line of the baseline below the peak temperature and the tangent line showing the maximum slope from the rising portion of the peak to the peak of the peak.

Production Example of Polyester Resin Compositions A to H and O to Q A propylene oxide adduct of bisphenol A (2.
2 mol) 71.3 parts by weight (54 mol%), terephthalic acid 28.7 parts by weight (46 mol%) and the tin compound shown in Table 1 are reacted under a nitrogen atmosphere at 235 ° C. until a desired softening point is reached. And the polyester resin compositions A to H,
O-Q were obtained.

Production Example of Polyester Resin Composition I The raw materials shown in Table 2 were reacted in a nitrogen atmosphere at 160 ° C. for 5 hours, then heated to 200 ° C. and reacted for 1 hour,
Further, the reaction was carried out at 8.3 kPa for 1 hour to obtain a polyester resin composition I.

[0040] BPA-PO usage shown in Production Examples in Table 2 of the polyester resin composition J, BPA-EO, terephthalic acid and di octane tin (II), under a nitrogen atmosphere, 2
After reacting at 30 ° C. for 8 hours, the temperature was lowered to 185 ° C., and Table 2
The fumaric acid, trimellitic anhydride, and hydroquinone shown in (1) were added and reacted for 1 hour. Next, the temperature was raised stepwise to 210 ° C. over 5 hours, and the reaction was carried out under reduced pressure at 8.3 kPa until the desired softening point was reached to obtain a polyester resin composition J.

Production Example of Polyester Resin Composition K BPA-PO, BPA-EO, terephthalic acid, trimellitic anhydride and tin dioctanoate (I
A mixture of styrene, acrylic acid, 2-ethylhexyl acrylate and di-t-butyl peroxide shown in Table 2 was added dropwise to the mixture of I) at 160 ° C. under a nitrogen atmosphere over 1 hour, and the mixture was further added for 2 hours. After carrying out the polymerization reaction,
The temperature was raised to 230 ° C. and the polycondensation reaction was performed until the desired softening point was reached to obtain a polyester resin composition K.

Production Example of Polyester Resin Composition L The raw materials shown in Table 2 were reacted in a nitrogen atmosphere at 235 ° C. for 7 hours, and then reacted at 8.3 kPa until a desired softening point was reached to obtain a polyester resin composition. A composition L was obtained.

Production Example of Polyester Resin Composition M Raw materials other than trimellitic anhydride shown in Table 2 were heated from 180 ° C. to 230 ° C. for 8 hours in a nitrogen atmosphere,
After reacting for another 2 hours, trimellitic anhydride was added at 200 ° C., and the reaction was continued until the desired softening point was reached.
A polyester resin composition M was obtained.

Production Example of Polyester Resin Composition N After heating raw materials other than trimellitic anhydride shown in Table 2 from 180 ° C. to 210 ° C. for 4 hours in a nitrogen atmosphere, trimellitic anhydride was added, and further 8 The reaction was carried out at 0.3 kPa until the desired softening point was reached to obtain a polyester resin composition N.

Tables 1 and 2 below show the softening point and glass transition point of the polyester resin composition.

[0046]

[Table 1]

[0047]

[Table 2]

Examples 1 to 20 and Comparative Examples 1 and 2 Binder resins, waxes, colorants, charge control agents and tin compounds shown in Table 3 were put into a Henschel mixer and stirred at a bath temperature of 40 ° C. for 3 minutes. Mix to obtain a mixture. The obtained mixture is melt-kneaded using a co-rotating twin-screw extruder with a heating temperature of 100 ° C. in a roll, and the resulting kneaded product is cooled and coarsely pulverized, then pulverized and classified by a jet mill to obtain a volume average. A powder having a particle size of 7.5 μm was obtained.

100 parts by weight of the obtained powder and hydrophobic silica "TS-530" (manufactured by Cabot Co., average particle size: 8 n)
m) 0.7 part by weight was mixed with stirring by a Henschel mixer for 3 minutes to obtain a toner.

Comparative Example 3 Using the raw materials shown in Table 3, in the same manner as in Example 1, powder having a volume average particle size of 7.5 μm was obtained. 100 parts by weight of the obtained powder, 2 parts by weight of tin (II) distearate and hydrophobic silica "TS-530" (manufactured by Cabot Co., average particle size:
(8 nm) 0.7 part by weight was mixed with a Henschel mixer for 3 minutes with stirring to obtain a toner.

The toners of all Examples and Comparative Examples are negatively chargeable toners, except that the toner obtained in Example 11 is a positively chargeable toner.

Test Example 1 [Evaluation of Charge Rising Property] 0.6 g of toner and silicone-coated ferrite carrier (Kanto Denka Kogyo KK, average particle size: 90 μm) 19.4
g with a ball mill at 250 r / min for a mixing time of 15 seconds, 30 seconds, 60 seconds, 120 seconds,
The electrification amount in 300 seconds is q / m meter (EPPI
(Manufactured by NG). The charge rising property was evaluated using the relative value of the charge amount at the mixing time of 15 seconds with respect to the maximum charge amount throughout. The results are shown in Table 3.

Test Example 2 [Evaluation of Underground Fogging of Solid Image] "Page Presto N-4" (manufactured by Casio Computer Co., Ltd.) equipped with a developing roll made of stainless steel (roll diameter: 2.3 cm) as a non-magnetic one-component developing device. ) Was mounted with toner, transfer was performed, and fixing was performed by an external fixing machine under the condition that offset did not occur. The negatively chargeable toner obtained in any other than Example 11 was mounted in this apparatus, and the printing test shown below was performed. The positively chargeable toner obtained in Example 11 was subjected to a printing test by an apparatus obtained by similarly modifying the facsimile "TF-58HW" (manufactured by Toshiba Corp.) modified for positive charge.

First, a 2 cm square solid image was formed at a position 2 cm from the center of the upper end of A4 blank paper. Next, (1) In the portion where the fog is seen by a solid image 2 cm below the circumference of the developing roller from the center of the upper end of 2 cm further from the center of the upper end, a square of 2 cm square and 0.5 cm inside each of the four corners and the width and width. Image density of 4 points of L ^*
It was measured by a color difference meter "CR-321" (manufactured by Minolta Co., Ltd.) by the a ^* b ^* method, and the average value was calculated. And (2)
Image densities at a total of 4 points were similarly measured on white paper portions at distances of 4 cm and 8 cm to the left and right from the center at a distance of 10.2 cm from the upper end of the center of the image, and the average value was calculated. The difference (ΔE) between the two values (1) and (2) was determined by the following formula, and the degree of fog generation was evaluated according to the following evaluation criteria. The results are shown in Table 3.

[0055]

[Equation 1]

[In the formula, L ₁ , a ₁ and b ₁ represent each measured value in (1), and L ₂ , a ₂ and b ₂ represent each measured value in (2). ]

[Evaluation Criteria] ⊚: ΔE is less than 0.5 ○: ΔE is 0.5 or more and less than 1 ×: ΔE is 1 or more and less than 3 XX: ΔE is 3 or more

[0058]

[Table 3]

From the above results, it is clear that, in comparison with the toners of the examples, all the toners of the comparative examples lack the charge rising property and are apt to cause fog. As a result, the effect of improving the charge buildup cannot be obtained with organic tin such as dibutyltin oxide, and even when an inorganic tin (II) compound is used, the effect cannot be obtained by external addition to the toner surface. I understand.

[0060]

According to the present invention, there are provided a catalyst for producing polyester, which is used in a toner having excellent charge rising property and hardly causing fog, a polyester resin composition containing the catalyst, and a toner containing the polyester resin composition. can do.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Eiji Shirai             1334 Minato Minato, Wakayama Kao Corporation             Within (72) Inventor Masayuki Maruta             1334 Minato Minato, Wakayama Kao Corporation             Within F-term (reference) 2H005 AA01 AB02 CA08 CB08                 4J029 AE18 BA08 BA09 BF26 CB04A                       CB05A CB06A FC03 FC36                       JA091 JB131 JB171 JF23                       JF371

Claims (6)

[Claims] 1. A catalyst for producing a polyester for toner, which comprises an inorganic tin (II) compound. 2. The catalyst according to claim 1, wherein the inorganic tin (II) compound is a tin compound having a Sn—O bond. 3. The inorganic tin (II) compound has 2 to 28 carbon atoms.
Carboxylic acid tin (II) with 2 carbon atoms
The catalyst according to claim 1 or 2, which is at least one member selected from the group consisting of dialkoxy tin (II) and tin oxide (II) having an alkoxy group of ~ 28. 4. A polyester resin composition containing polyester and the catalyst according to claim 1. 5. The polyester resin composition according to claim 4, wherein the polyester is a resin obtained by using a dihydric or higher valent secondary alcohol and / or a divalent or higher valent aromatic carboxylic acid compound as at least a raw material monomer. 6. A toner containing the polyester resin composition according to claim 4 or 5.