JP6854189B2 - Toner manufacturing method - Google Patents

Description

The present invention relates to a method for producing toner used for developing a latent image formed by an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.

In recent years, toner having excellent low-temperature fixability has been demanded from the viewpoint of speeding up the printing apparatus and saving energy.

Crystalline polyester has crystallinity and contributes to improvement of low-temperature fixability, but since it is partially compatible with the amorphous resin when it is melted, the compatible part becomes thermally weak and is easily broken when crushed. It becomes easy to appear on the surface. If a large amount of crystalline polyester is present on the surface of the toner, the charging member (carrier, developing roller) is likely to be contaminated, and the durability is deteriorated.

In response to such problems, for example, Patent Document 1 describes an electrophotographic toner containing a crystalline resin, an amorphous resin, and a mold release agent, wherein the crystalline resin contains a specific component. The amorphous composite resin C is contained, the amorphous resin contains the amorphous composite resin A containing a specific component, the average circularity of the toner is 0.940 or more, and the particle size in the toner is It is disclosed that an electrophotographic toner having a particle content of 3 μm or less of 5.0% by number or less is an electrophotographic toner having excellent low-temperature fixability and durability and suppressing paper wrapping during fixing. ..

Japanese Unexamined Patent Publication No. 2016-114829

However, the toner produced by the method described in Patent Document 1 still cannot be said to have sufficient low-temperature fixability and durability, and further improvement is desired.

The present invention relates to a method for producing a toner having excellent low temperature fixability and durability.

The present invention relates to a method for producing a toner, which comprises a spheroidizing step of spheroidizing toner particles containing a crystalline polyester resin and an amorphous polyester resin with a mechanical surface modifier equipped with a hammer and a liner. ..

By the method of the present invention, a toner having excellent low temperature fixability and durability can be obtained.

It is the schematic sectional drawing of one Embodiment of the surface modification apparatus used in this invention. It is a top view of one Embodiment of the rotating body in FIG. It is the schematic sectional drawing of one Embodiment of the surface modification apparatus used in this invention.

A major feature of the method of the present invention is that it includes a spheroidizing step of spheroidizing toner particles containing a crystalline polyester resin and an amorphous polyester resin with a mechanical surface modifier equipped with a hammer and a liner. Has. The crystalline polyester-based resin has crystallinity and contributes to the improvement of low-temperature fixability, but since it is partially compatible with the amorphous resin at the time of melting, the compatible portion becomes thermally weakened, and it is broken during pulverization. Easy to form corners. If the crystalline polyester resin is excessively exposed on the toner surface, the charged members (carriers, developing rollers) are likely to be contaminated, and the durability is deteriorated. Therefore, in the present invention, the area of the crystalline polyester resin on the surface of the toner particles can be reduced by subjecting the toner particles to a spherical treatment using a mechanical surface modifier equipped with a hammer and a liner. A toner with excellent durability can be obtained. In the spheroidizing process in which heat is applied to the surface of the toner particles, such as the mechanical crusher using friction and the thermal spheroidizing process that have been widely used in the past, the phase between the crystalline polyester resin and the amorphous polyester resin While the area of the crystalline polyester resin newly exposed on the surface increases with the spheroidization due to the dissolution of the melted portion, in the present invention, particularly the corner portion of the toner particle surface can be efficiently scraped. The area of the crystalline polyester resin on the surface of the toner particles can be reduced.

The toner particles to be subjected to the spheroidizing treatment contain a crystalline polyester-based resin and an amorphous polyester-based resin as the binder resin. The crystallinity of a resin is represented by the crystallinity index defined by the ratio of the softening point to the maximum endothermic temperature measured by the differential scanning calorimeter, that is, the value of [softening point / maximum endothermic temperature]. The crystalline resin is an amorphous resin having a crystallinity index of 0.6 or more, preferably 0.7 or more, more preferably 0.9 or more, and 1.4 or less, preferably 1.2 or less, more preferably 1.1 or less. Is a resin having a crystallinity index of more than 1.4, preferably more than 1.5, more preferably 1.6 or more, or less than 0.6, preferably 0.5 or less. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers, the production conditions (for example, reaction temperature, reaction time, cooling rate) and the like. The maximum endothermic temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks. In the crystalline resin, the maximum peak temperature of endothermic is defined as the melting point.

The crystalline polyester resin contains a crystalline polyester resin which is a polycondensate of an alcohol component containing a divalent or higher alcohol and a carboxylic acid component containing a divalent or higher carboxylic acid compound, and contains 90 mol of an aliphatic monomer. It is preferably a polycondensate of the raw material monomer containing% or more. The content of the aliphatic monomer is more preferably 95 mol% or more, still more preferably 100 mol%, in the raw material monomer of the crystalline polyester resin.

The alcohol component of the crystalline polyester resin preferably contains an aliphatic diol having 9 or more and 14 or less carbon atoms from the viewpoint of compatibility with the amorphous polyester resin.

Examples of the aliphatic diol having 9 or more and 14 or less carbon atoms include 1,9-nonane diol, 1,10-decane diol, 1,11-undecane diol, and 1,12-dodecane diol.

The carbon number of the aliphatic diol is preferably 9 or more, more preferably 10 or more from the viewpoint of lowering the compatibility with the amorphous polyester, and preferably 14 or less, more preferably from the viewpoint of low temperature fixability. Is 12 or less.

Further, the aliphatic diol having 9 or more and 14 or less carbon atoms preferably has a hydroxyl group at the end of the carbon chain from the viewpoint of improving the low temperature fixability of the toner, and is an α, ω-linear alkane diol. Is more preferable.

The alcohol component may contain alcohols other than the aliphatic diol having 9 or more and 14 or less carbon atoms, but the content of the aliphatic diol having 9 or more and 14 or less carbon atoms is from the viewpoint of low temperature fixability and durability. Therefore, the alcohol component is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, still more preferably 100 mol% or more.

As alcohol components other than aliphatic diols having 9 or more and 14 or less carbon atoms, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1, Examples thereof include aliphatic diols having 2 to 8 carbon atoms such as 7-heptanediol and 1,8-octanediol, aromatic diols such as alkylene oxide adducts of bisphenol A, and trihydric or higher alcohols such as glycerin.

The carboxylic acid component of the crystalline polyester resin preferably contains an aliphatic dicarboxylic acid compound having 9 or more and 14 or less carbon atoms.

Aliphatic dicarboxylic acid compounds having 9 or more and 14 or less carbon atoms include azelaic acid (carbon number: 9), sebacic acid (carbon number: 10), dodecanedioic acid (carbon number: 12), and tetradecanedioic acid (carbon number: 12). : 14), succinic acid having an alkyl group or an alkenyl group in the side chain, anhydrides of these acids, alkyl esters having 1 to 3 carbon atoms thereof and the like. In the present invention, the carboxylic acid compound includes not only free acids, but also anhydrides that decompose during the reaction to generate acids, and alkyl esters having an alkyl group having 1 or more and 3 or less carbon atoms. However, the carbon number of the alkyl group in the alkyl ester portion is not included in the carbon number of the aliphatic dicarboxylic acid compound.

The chain hydrocarbon group in the aliphatic dicarboxylic acid compound may be a straight chain or a branched chain, and the carbon number of the aliphatic dicarboxylic acid compound is preferably 9 or more from the viewpoint of durability. And, from the viewpoint of low temperature fixability, it is preferably 14 or less, more preferably 12 or less.

The content of the aliphatic dicarboxylic acid compound having 9 or more and 14 or less carbon atoms is preferably 70 mol or more, more preferably 80 mol or more, and more preferably 80 mol or more, based on 100 mol of the alcohol component, from the viewpoint of heat storage stability. From the viewpoint of low-temperature fixability, it is preferably 130 mol or less, more preferably 120 mol or less.

The carboxylic acid component may contain a carboxylic acid compound other than the aliphatic dicarboxylic acid compound having 9 or more and 14 or less carbon atoms, but the content of the aliphatic dicarboxylic acid compound having 9 or more and 14 or less carbon atoms. Is preferably 85 mol% or more, more preferably 87 mol% or more, still more preferably 90 mol% or more, still more preferably 100 mol% or more in the carboxylic acid component.

Other carboxylic acid compounds include aromatic dicarboxylic acid compounds such as terephthalic acid and isophthalic acid, aliphatic dicarboxylic acid compounds having 2 to 8 carbon atoms, trimellitic acid, pyromellitic acid and other trivalent or higher carboxylic acids. Acid compounds and the like can be mentioned.

The polycondensation reaction with the carboxylic acid component and the alcohol component is carried out at 180 ° C. or higher in an inert gas atmosphere, preferably in the presence of an esterification catalyst and, if necessary, in the presence of an esterification co-catalyst or the like. It can be carried out at a temperature of 250 ° C. or lower. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropyrate bistriethanolamite. Examples of the esterification co-catalyst that can be used together with the esterification catalyst include gallic acid and the like. The amount of the esterification catalyst used is preferably 0.01 part by mass or more, more preferably 0.1 part by mass or more, and preferably 1 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. It is preferably 0.6 parts by mass or less. The amount of the esterification co-catalyst used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less.

In the present invention, the crystalline polyester resin is preferably a crystalline composite resin containing the crystalline polyester resin and the styrene resin from the viewpoint of durability.

The styrene-based resin is an addition polymer of a raw material monomer containing at least styrene or a styrene derivative such as α-methylstyrene or vinyltoluene (hereinafter, styrene and styrene derivative are collectively referred to as “styrene compound”).

The content of the styrene compound, preferably styrene, is preferably 50% by mass or more, more preferably 70% by mass, from the viewpoint of improving the dispersion stability of the toner particles and improving the storage stability in the raw material monomer of the styrene resin. The above is more preferably 80% by mass or more, and from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 95% by mass or less, more preferably 93% by mass or less, still more preferably 90% by mass or less.

Further, the styrene resin may contain a (meth) acrylic acid alkyl ester having 7 or more carbon atoms as an alkyl group as a raw material monomer. Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid (iso) octyl, (meth) acrylic acid (iso) decyl, and (meth) acrylic acid (iso) stearyl. Can be mentioned. It is preferable to use one or more of these. In addition, in this specification, "(iso)" means including both the case where this group is present and the case where this group is not present, and is normal when these groups are not present. Show that. Further, "(meth) acrylic acid" indicates acrylic acid, methacrylic acid, or both.

The carbon number of the alkyl group in the (meth) acrylic acid alkyl ester as the raw material monomer of the styrene resin is preferably 7 or more, more preferably 8 or more, and preferably 8 or more, from the viewpoint of improving the low temperature fixability of the toner. Is 12 or less, more preferably 10 or less. The carbon number of the alkyl ester refers to the number of carbon atoms derived from the alcohol component constituting the ester.

Examples of the raw material monomer of the styrene resin other than the styrene compound and the (meth) acrylic acid alkyl ester include ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; and halovinyls such as vinyl chloride; Vinyl esters such as vinyl acetate and vinyl propionate; Ethylene monocarboxylic acid esters such as dimethylaminoethyl (meth) acrylate; Vinyl ethers such as vinyl methyl ether; Vinylidene halides such as vinylidene chloride; N-vinylpyrrolidone and the like N-vinyl compounds and the like.

The addition polymerization reaction of the raw material monomer of the styrene resin is carried out, for example, in the presence of a polymerization initiator such as dicumyl peroxide, a polymerization inhibitor, a cross-linking agent, etc., in the presence of an organic solvent or in the absence of a solvent, if necessary. Although it can be carried out by a conventional method, the temperature conditions are preferably 110 ° C. or higher, more preferably 140 ° C. or higher, and preferably 200 ° C. or lower, more preferably 170 ° C. or lower.

When an organic solvent is used in the addition polymerization reaction, xylene, toluene and the like can be used. The amount of the organic solvent used is preferably 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the raw material monomer of the styrene resin.

In the crystalline composite resin, the crystalline polyester resin and the styrene resin are chemically bonded via both reactive monomers capable of reacting with both the raw material monomer of the crystalline polyester resin and the raw material monomer of the styrene resin. Is preferable.

The bireactive monomer contains at least one functional group selected from the group consisting of a hydroxyl group, a carboxy group, an epoxy group, a primary amino group and a secondary amino group, preferably a hydroxyl group and / or a carboxy group. A group, more preferably a compound having a carboxy group and an ethylenically unsaturated bond, is preferable, and at least one selected from the group consisting of acrylic acid, methacrylic acid, fumaric acid, maleic acid and maleic anhydride is more preferable. From the viewpoint of the reactivity of the polycondensation reaction and the addition polymerization reaction, at least one selected from the group consisting of acrylic acid, methacrylic acid and fumaric acid is more preferable. However, when used together with a polymerization inhibitor, a polyvalent carboxylic acid compound having an ethylenically unsaturated bond such as fumaric acid functions as a raw material monomer for a polyester resin. In this case, fumaric acid and the like are not bireactive monomers but raw material monomers of polyester resin.

From the viewpoint of low-temperature fixability, the amount of both reactive monomers used is preferably 1 mol or more, more preferably 2 mol or more, and styrene-based, with respect to a total of 100 mol of the alcohol component of the crystalline polyester resin. From the viewpoint of enhancing the dispersibility between the resin and the crystalline polyester resin and improving the durability of the toner, the amount is preferably 30 mol or less, more preferably 20 mol or less, and further preferably 10 mol or less.
From the viewpoint of low-temperature fixability, the amount of both reactive monomers used is preferably 1 part by mass or more, more preferably 2 parts by mass or more, based on 100 parts by mass of the total raw material monomers of the styrene resin. Then, from the viewpoint of enhancing the dispersibility between the styrene resin and the crystalline polyester resin and improving the durability of the toner, the content is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and further preferably 10 parts by mass or less. is there. Here, the polymerization initiator is included in the total of the raw material monomers of the styrene resin.

Specifically, the crystalline composite resin is preferably produced by the following method. When bireactive monomers are used, the bireactive monomers are used in the addition polymerization reaction together with the raw material monomers of the styrene resin from the viewpoint of improving the durability of the toner, the low temperature fixability of the toner and the heat storage stability. Is preferable.

(i) A method in which the step (A) of the polycondensation reaction using the raw material monomer of the polyester resin is followed by the step (B) of the addition polymerization reaction using the raw material monomer of the styrene resin and the bireactive monomer. The step (A) is carried out under the reaction temperature condition suitable for the above, the reaction temperature is lowered, and the step (B) is carried out under the temperature condition suitable for the addition polymerization reaction. The raw material monomer of the styrene resin and the bireactive monomer are preferably added into the reaction system at a temperature suitable for the addition polymerization reaction. Both reactive monomers undergo an addition polymerization reaction and also react with a polyester resin.
After the step (B), the reaction temperature is raised again, and if necessary, a raw material monomer of a polyester resin having a valence of 3 or more as a cross-linking agent is added to the polymerization system, and the polycondensation reaction and both reactions in the step (A) are carried out. The reaction with the sex monomer can be further advanced.

(ii) A method of carrying out a polycondensation reaction step (A) using a polyester resin raw material monomer after an addition polymerization reaction step (B) using a styrene resin raw material monomer and a bireactive monomer In this method, an addition polymerization reaction is performed. The polycondensation reaction of the step (A) is carried out under the temperature conditions suitable for the polycondensation reaction by raising the reaction temperature by carrying out the step (B) under the reaction temperature conditions suitable for the above. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.
The raw material monomer of the polyester resin may be present in the reaction system during the addition polymerization reaction, or may be added to the reaction system under temperature conditions suitable for the polycondensation reaction. In the former case, the progress of the polycondensation reaction can be adjusted by adding an esterification catalyst at a temperature suitable for the polycondensation reaction.

(iii) The reaction is carried out under the condition that the step (A) of the polycondensation reaction using the raw material monomer of the polyester resin and the step (B) of the polycondensation reaction using the raw material monomer of the styrene resin and the bireactive monomer proceed in parallel. Method of performing In this method, the steps (A) and (B) are performed in parallel under the reaction temperature conditions suitable for the polycondensation reaction, the reaction temperature is raised, and the temperature conditions suitable for the polycondensation reaction are used. If necessary, it is preferable to add a raw material monomer of a trivalent or higher valent polyester resin as a cross-linking agent to the polymerization system to further carry out the polycondensation reaction in the step (A). At that time, under temperature conditions suitable for the polycondensation reaction, a polymerization inhibitor may be added to proceed only with the polycondensation reaction. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.

In the method (i) above, a pre-polymerized polycondensation resin may be used instead of the step (A) in which the polycondensation reaction is carried out. In the method (iii) above, when the reaction is carried out under the condition that the steps (A) and (B) proceed in parallel, the raw material monomer of the styrene resin is contained in the mixture containing the raw material monomer of the polyester resin. The mixture containing the above can also be dropped and reacted.

The above methods (i) to (iii) are preferably performed in the same container.

The mass ratio of the crystalline polyester resin to the styrene resin (crystalline polyester resin / styrene resin) in the crystalline composite resin is preferably 98/2 or less, more preferably 95/5 or less, and further, from the viewpoint of pulverizability. It is preferably 90/10 or less, and from the viewpoint of low temperature fixability, it is preferably 60/40 or more, more preferably 70/30 or more, and further preferably 80/20 or more. In the above calculation, the mass of the polyester resin is the amount obtained by subtracting the amount of reaction water (calculated value) dehydrated by the polycondensation reaction from the mass of the raw material monomer of the polyester resin used, and is a bireactive monomer. Is included in the amount of raw material monomer of the polyester resin. The amount of the styrene resin is the amount of the raw material monomer of the styrene resin, but the amount of the polymerization initiator is included in the amount of the raw material monomer of the styrene resin.

The softening point of the crystalline polyester resin is preferably 80 ° C. or higher, more preferably 85 ° C. or higher from the viewpoint of toner durability, and preferably 110 ° C. or lower, more preferably from the viewpoint of low temperature fixability. Is below 100 ° C.

The melting point of the crystalline polyester resin is preferably 70 ° C. or higher, more preferably 80 ° C. or higher from the viewpoint of toner durability, and preferably 110 ° C. or lower, more preferably 110 ° C. or lower from the viewpoint of low temperature fixability. It is 100 ° C or less.

The content of the crystalline polyester resin is preferably 3% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and the toner in the binder resin from the viewpoint of low-temperature fixability. From the viewpoint of durability, it is preferably 35% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less.

The amorphous polyester resin contains an amorphous polyester resin which is a polycondensate of an alcohol component containing a divalent or higher alcohol and a carboxylic acid component containing a divalent or higher carboxylic acid compound.

Examples of the divalent alcohol include an aliphatic diol, preferably an aliphatic diol having 2 or more and 20 or less carbon atoms, and more preferably 2 or more and 15 or less carbon atoms, or the formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is ethylene and / or propylene group, x and y indicate the average number of moles of alkylene oxide added, which are positive numbers, respectively, of x and y. The value of the sum is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, more preferably 6 or less, still more preferably 4 or less).
Examples thereof include an alkylene oxide adduct of bisphenol A represented by, bisphenol A, hydrogenated bisphenol A and the like. Specific examples of the aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, and 1,6-hexanediol.

As the alcohol component, an alkylene oxide adduct of bisphenol A represented by the formula (I) is preferable from the viewpoint of toner durability. The content of the alkylene oxide adduct of bisphenol A represented by the formula (I) is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol% or more, still more preferably 90 mol% or more in the alcohol component. It is 95 mol% or more, more preferably 100 mol%.

Examples of the divalent carboxylic acid compound include dicarboxylic acids having 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, and more preferably 3 to 10 carbon atoms, anhydrides thereof, or alkyl groups. Examples thereof include derivatives such as alkyl esters having 1 or more and 3 or less carbon atoms. Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, fumaric acid, maleic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, and alkyl having 1 to 20 carbon atoms. Examples thereof include aliphatic dicarboxylic acids such as succinic acid substituted with a group or an alkenyl group having 2 or more and 20 or less carbon atoms.

Examples of the trivalent or higher carboxylic acid compound include trivalent or higher carboxylic acids having 4 or more and 20 or less carbon atoms, preferably 6 or more and 20 or less carbon atoms, their anhydrides, or an alkyl group having 1 or more carbon atoms. Examples thereof include derivatives such as alkyl esters of 3 or less. Specific examples thereof include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid), and acid anhydrides thereof.

The alcohol component may contain a monohydric alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound as appropriate from the viewpoint of adjusting the molecular weight and softening point of the polyester resin.

The equivalent ratio (COOH group / OH group) of the carboxylic acid component and the alcohol component in the polyester resin is preferably 0.6 or more, more preferably 0.7 or more, still more preferably 0.75 or more from the viewpoint of adjusting the softening point of the polyester resin. Yes, and preferably 1.2 or less, more preferably 1.15 or less.

The polyester resin preferably contains, for example, an alcohol component and a carboxylic acid component in an inert gas atmosphere, preferably in the presence of an esterification catalyst, and if necessary, in the presence of an esterification co-catalyst, a polymerization inhibitor, or the like. It can be produced by polycondensation at a temperature of 130 ° C. or higher, more preferably 170 ° C. or higher, and preferably 250 ° C. or lower, more preferably 240 ° C. or lower.

Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropyrate bistriethanolaminate, and tin compounds are preferable. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1.5 parts by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. It is preferably 1 part by mass or less. Examples of the esterification co-catalyst include gallic acid and the like. The amount of the esterification co-catalyst used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less. Examples of the polymerization inhibitor include t-butylcatechol and the like. The amount of the polymerization inhibitor used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. It is preferably 0.1 parts by mass or less.

In the present invention, the amorphous polyester resin may be a polyester resin modified to such an extent that its characteristics are not substantially impaired. Examples of the modified polyester resin include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636 and the like. Examples of the modified polyester resin include a modified polyester resin, and among the modified polyester resins, a urethane-modified polyester resin obtained by urethane-extending the polyester resin with a polyisocyanate compound is preferable.

In the present invention, the amorphous polyester resin is preferably an amorphous composite resin containing the amorphous polyester resin and the styrene resin from the viewpoint of low temperature fixability. The composite resin is the same as the crystalline composite resin except that the polyester resin is an amorphous polyester resin instead of a crystalline polyester resin.

The softening point of the amorphous polyester resin is preferably 80 ° C. or higher, more preferably 85 ° C. or higher from the viewpoint of storage stability, and preferably 130 ° C. or lower, more preferably from the viewpoint of low temperature fixability. Is below 120 ° C.

When the amorphous polyester resin is composed of two or more kinds of resins, the weighted average value thereof is preferably within the above range, and in the present invention, the amorphous polyester resin is used from the viewpoint of fixability. Preferably contains two types of amorphous polyester resins having different softening points. The difference in softening points between the two amorphous polyester resins is preferably 5 ° C. or higher, more preferably 10 ° C. or higher.

The softening point of the amorphous polyester resin H having the higher softening point is preferably 110 ° C. or higher, more preferably 120 ° C. or higher, and the toner, from the viewpoint of improving the durability and heat-resistant storage stability of the toner. From the viewpoint of improving the low temperature fixability, the temperature is preferably 160 ° C. or lower, more preferably 150 ° C. or lower, and further preferably 140 ° C. or lower. Further, the softening point of the amorphous polyester resin L having the lower softening point is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, and the low temperature of the toner, from the viewpoint of improving the durability of the toner. From the viewpoint of improving the fixability, the temperature is preferably 135 ° C. or lower, more preferably 120 ° C. or lower, and further preferably 115 ° C. or lower.

The mass ratio of the amorphous polyester resin H to the amorphous polyester resin L (amorphous polyester resin H / amorphous polyester resin L) is preferably 5/95 or more, more preferably 10/90. The above, and preferably 45/55 or less, more preferably 42/58 or less. Of the resin having a high softening point and the resin having a low softening point, the resin having a low softening point is more easily cracked, and usually, if there are many resins having a low softening point, the durability is disadvantageous. Since the interface of the crystalline polyester resin is more easily cracked than the quality polyester resin, even if a large amount of the amorphous polyester resin L having a low softening point is contained, the durability is not deteriorated. The effect of the invention is more prominent.

The glass transition temperature of the amorphous polyester resin is preferably 40 ° C. or higher, more preferably 50 ° C. or higher from the viewpoint of storage stability, and preferably 80 ° C. or lower, more preferably from the viewpoint of low temperature fixability. It is preferably 70 ° C. or lower.

The acid value of the amorphous polyester resin is preferably 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, still more preferably 5 mgKOH / g or more, and from the viewpoint of hygroscopicity, from the viewpoint of the rising property of charging. Therefore, it is preferably 20 mgKOH / g or less, and more preferably 15 mgKOH / g or less.

The content of the amorphous polyester resin is preferably 65% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and from the viewpoint of low-temperature fixability in the binder resin. From the viewpoint of durability, it is preferably 97% by mass or less, more preferably 95% by mass or less.

The mass ratio of the crystalline polyester resin to the amorphous polyester resin (crystalline polyester resin / amorphous polyester resin) in the binder resin is preferably 3/97 or more from the viewpoint of storage stability. It is preferably 5/95 or more, and from the viewpoint of low-temperature fixability, it is preferably 35/65 or less, more preferably 30/70 or less, and further preferably 20/80 or less.

As the binder resin, a known resin other than the above-mentioned crystalline polyester resin and amorphous polyester resin may be used in combination as long as the effect of the present invention is not impaired, but the content of both resins is , 90% by mass or more, more preferably 93% by mass or more, still more preferably 95% by mass or more, still more preferably 100% by mass, in the binder resin.

The toner particles are preferably obtained by a method including a kneading step of melt-kneading a composition containing a crystalline polyester-based resin and an amorphous polyester-based resin, and a crushing step of pulverizing the obtained kneaded product.

Compositions to be subjected to melt-kneading include colorants, mold release agents, charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, and cleanability improvers. Etc. may be contained.

As the colorant, dyes, pigments, magnetic substances and the like used as colorants for toner can be used. For example, carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmin 6B, isoindoline, disazoero, etc. .. In the present invention, the toner particles may be either black toner or color toner.

The content of the colorant is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and preferably 40 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of improving the image density of the toner. Parts or less, more preferably 20 parts by mass or less, still more preferably 10 parts by mass or less.

As the release agent, hydrocarbon waxes such as polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystallin wax, paraffin wax, Fishertropch wax, sazole wax and their oxides; carnauba wax, montan Waxes and ester waxes such as deoxidizing waxes and fatty acid ester waxes; fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts and the like can be mentioned, and these can be used alone or in combination of two or more. Among these, carnauba wax is preferable from the viewpoint of durability.

The melting point of the release agent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher from the viewpoint of toner transferability, and preferably 160 ° C. or lower, more preferably 140 ° C. or higher from the viewpoint of low temperature fixability. Below, it is more preferably 130 ° C. or lower, still more preferably 120 ° C. or lower.

The content of the release agent is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the binder resin from the viewpoint of low temperature fixability and offset resistance of the toner and dispersibility in the binder resin. It is preferably 1 part by mass or more, more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass or less, still more preferably 7 parts by mass or less.

The charge control agent is not particularly limited, and may contain either a positive charge control agent or a negative charge control agent.

Positive charge control agents include niglosin dyes such as "niglosin base EX", "oil black BS", "oil black SO", "bontron N-01", "bontron N-04", and "bontron N-07". , "Bontron N-09", "Bontron N-11" (all manufactured by Orient Chemical Industry Co., Ltd.), etc .; Triphenylmethane dyes containing a tertiary amine as a side chain, a quaternary ammonium salt compound, for example. "Bontron P-51" (manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant), etc .; (Manufactured), etc .; imidazole derivatives such as "PLZ-2001", "PLZ-8001" (all manufactured by Shikoku Kasei Kogyo Co., Ltd.), etc .; styrene-acrylic resin, for example "FCA-701PT" (Fujikura Kasei Co., Ltd.) (Manufactured) and the like.

As the negative charge control agent, metal-containing azo dyes such as "Varifast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", and "Bontron S-36" (Above, manufactured by Orient Chemical Industry Co., Ltd.), "Eisenspiron Black TRH", "T-77" (manufactured by Hodoya Chemical Industry Co., Ltd.), etc .; 147 ”,“ LR-297 ”(above, manufactured by Nippon Carlit Co., Ltd.); metal compounds of salicylic acid compounds, for example,“ Bontron E-81 ”,“ Bontron E-84 ”,“ Bontron E-88 ”,“ Bontron E-304 "(above, manufactured by Orient Chemical Industry Co., Ltd.)," TN-105 "(manufactured by Hodoya Chemical Industry Co., Ltd.), etc .; copper phthalocyanine dye; quaternary ammonium salt, for example," COPY CHARGE NX VP434 " (Manufactured by Clariant), nitroimidazole derivatives and the like; organic metal compounds and the like.

The content of the charge control agent is preferably 0.01 part by mass or more, more preferably 0.2 part by mass or more, and preferably 10 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of charge stability of the toner. Parts or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, still more preferably 2 parts by mass or less.

The composition to be subjected to melt-kneading may be subjected to kneading all at once or divided and subjected to kneading, but it is preferable that the composition is mixed in advance with a mixer such as a Henschel mixer or a ball mill and then supplied to the kneader.

The melt kneading can be performed by using a known kneader such as a closed kneader, a single-screw or two-screw extruder, or an open roll type kneader. From the viewpoint of reducing the temperature during melt kneading and improving the durability of the toner, it is preferable to use an open roll type kneader, and the open roll type kneader is kneaded with a supply port along the axial direction of the roll. It is preferable that a substance discharge port is provided.

The open roll type kneader is one in which the kneading portion is not sealed and is open, and the kneading heat generated during kneading can be easily dissipated. Further, the continuous open roll type kneader is preferably a kneader having at least two rolls, and the continuous open roll type kneader used in the present invention has two rolls having different peripheral speeds. That is, it is preferable that the kneader is provided with two rolls, a high rotation side roll having a high peripheral speed and a low rotation side roll having a low peripheral speed. In the present invention, the rotation speed is high from the viewpoint of improving the dispersibility of the release agent in the binder resin, reducing the mechanical force during melt-kneading and suppressing heat generation, and improving the durability of the toner. It is preferable that the side roll is a heating roll and the low rotation side roll is a cooling roll.

The temperature of the roll can be adjusted by, for example, the temperature of the heat medium passed through the inside of the roll, and the inside of the roll may be divided into two or more and heat media having different temperatures may be passed through each roll.

The temperature at the end of the high-speed roll on the raw material input side is preferably 80 ° C. or higher and 160 ° C. or lower from the viewpoint of reducing mechanical force during melt-kneading and suppressing heat generation and improving the durability of the toner. From the same viewpoint, the temperature at the end of the low rotation side roll on the raw material input side is preferably 30 ° C. or higher and 100 ° C. or lower.

In the high-speed roll, the difference in set temperature between the end on the raw material input side and the end on the discharge side of the kneaded material reduces the mechanical force during melt-kneading from the viewpoint of preventing the kneaded material from coming off from the roll and suppresses heat generation. From the viewpoint of improving the durability of the toner, the temperature is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, and preferably 60 ° C. or lower, more preferably 50 ° C. or lower. The low rotation side roll reduces the mechanical force during melt kneading from the viewpoint of improving the dispersibility of the release agent in the binder resin due to the difference in the set temperature between the raw material input side end and the kneaded material discharge side end. From the viewpoint of suppressing heat generation and improving the durability of the toner, the temperature is preferably 0 ° C. or higher, and preferably 50 ° C. or lower.

The peripheral speed of the roll on the high rotation side is from the viewpoint of improving the dispersibility of the release agent in the binder resin, from the viewpoint of reducing the mechanical force during melt kneading and suppressing heat generation, and from the viewpoint of improving the durability of the toner. Therefore, it is preferably 2 m / min or more, more preferably 10 m / min or more, further preferably 25 m / min or more, and preferably 100 m / min or less, more preferably 75 m / min or less, still more preferably 50 m / min. It is as follows. From the same viewpoint, the peripheral speed of the low rotation side roll is preferably 1 m / min or more, more preferably 5 m / min or more, further preferably 15 m / min or more, and preferably 90 m / min or less, more preferably. Is 60 m / min or less, more preferably 30 m / min or less. Further, the ratio of the peripheral speeds of the two rolls (low rotation side roll / high rotation side roll) is preferably 1/10 or more, more preferably 3/10 or more, and preferably 9/10 or less. More preferably, it is 8/10 or less.

The structure, size, material, etc. of each roll are not particularly limited. The surface of the roll has a groove used for kneading, and the shape thereof includes a linear shape, a spiral shape, a corrugated shape, and an uneven shape.

After melt-kneading, it is preferable that the kneaded product is appropriately cooled until it reaches a pulverizable hardness, and a pulverization step and, if necessary, a classification step are performed to obtain toner particles. Here, cooling means cooling the kneaded product to 0 ° C. or higher and 50 ° C. or lower, or cooling the kneaded product to a glass transition temperature or lower of the binder resin in the kneaded product.

The pulverization step is a step of pulverizing the obtained kneaded product to obtain toner particles, and in the present invention, the kneaded product is preferably pulverized by a jet mill. The kneaded product may be pulverized at once or stepwise to a desired particle size, but from the viewpoint of efficient and more uniform pulverization, it is carried out in two stages of coarse pulverization and fine pulverization. It is preferable to use a jet mill for grinding.

Examples of the crusher used for coarse crushing include a hammer mill, an atomizer, and a rotoplex.

In coarse pulverization, it is preferable to pulverize until the maximum diameter becomes 3 mm or less. For a pulverized product having a maximum diameter of 3 mm or less, the kneaded product is appropriately roughly pulverized until the particle size is 0.05 mm or more and 3 mm or less, and then passed through a sieve having a mesh opening of 3 mm to obtain a pulverized product that has passed through the sieve. Can be done.

Examples of the pulverizer used for fine pulverization include a fluidized bed type jet mill, a jet mill such as an air flow type jet mill, a mechanical type mill, and the like. The formula jet mill is more preferable. A fluidized bed type jet mill having at least a crushing chamber in which a plurality of jet nozzles are arranged so as to face each other is more preferable because the fluidity is easily maintained because the toners are crushed by the collision of the toners.

In the fluidized bed type jet mill, a fluidized bed of particles supplied into the pulverization vessel is formed by a high-speed gas jet ejected from a jet nozzle, and the particles are repeatedly accelerated and collided with each other in the fluidized bed. It has a structure / principle in which particles are finely pulverized.

In the fluidized bed type jet mill having the above structure, the number of jet nozzles is not particularly limited, but from the viewpoint of the balance of air volume, flow rate, flow velocity, collision efficiency of particles, etc., a plurality of jet nozzles, preferably 3 to 4 jet nozzles are used. , It is preferable that they are arranged so as to face each other.

Further, a classification rotor may be provided in the upper portion of the crushing chamber to collect the particles having a small particle size which has been reduced by crushing and the increased small particle size. The particle size distribution can be easily adjusted by the rotation speed of the classification rotor. By classification with a classification rotor, a pulverized product from which coarse powder has been removed (upper limit classification powder) can be obtained.

The classification rotor may be arranged vertically or horizontally with respect to the vertical direction, but is preferably arranged vertically from the viewpoint of classification performance.

Specific examples of the fluidized bed type jet mill provided with a plurality of jet nozzles and further having a classification rotor include the crushers disclosed in JP-A-60-166547 and JP-A-2002-35631.

Examples of commercially available fluidized bed jet mills preferably used in the present invention include the "TFG" series and "AFG" series manufactured by Hosokawa Micron Co., Ltd.

The degree of fine pulverization is preferably adjusted as appropriate according to the particle size of the target toner.

Examples of the classifier used in the classification process include an airflow type classifier, an inertial type classifier, and a sieve type classifier.

Subsequently, a spheroidization step is performed in which the obtained toner particles are spheroidized by a mechanical surface modifier equipped with a hammer and a liner. The mechanical surface modifier used in the present invention is preferably a batch type surface modifier. The batch type surface modification device includes a classification means for continuously discharging and removing fine powder to the outside of the device, a surface treatment means provided with a hammer and a liner, and a first space for introducing an object to be treated into the classification means. An apparatus having a guide means for partitioning the inside of the apparatus with a second space for introducing the object to be treated into the surface treatment means is preferable.

The sphericalization (also referred to as surface modification) treatment using the batch type surface modification device will be specifically described with reference to the drawings.

FIG. 1 shows an example of a surface modifying apparatus used in the present invention, and FIG. 2 shows an example of a top view of a rotating body rotating at high speed in FIG.

The surface modifier shown in FIG. 1 is
Casing 13,
Jacket that allows cooling water or antifreeze to pass through (not shown),
Dispersion rotor 6, which is a surface treatment means, is a rotating body on a disk that has a plurality of hammers 10 on the upper surface and is attached to a central rotating shaft in a casing 13 and rotates at high speed.
Liner 4 (fixed body) having a large number of grooves on the surface of the dispersion rotor 6 arranged at regular intervals (there may be no grooves on the liner surface),
Classification rotor 1, which is a means for classifying a surface-modified object to be treated into a predetermined particle size,
Fine powder discharge port 2 for discharging and removing fine powder with a predetermined particle size or less selected by a classification rotor,
Cold air inlet for introducing cold air 5,
Raw material supply port 3 for introducing the object to be processed into the first space 11,
Discharge valve 8 installed so that it can be opened and closed so that the surface modification time can be adjusted freely.
The powder discharge port 7 for discharging the processed powder and the space between the classification zone and the surface modification zone in the apparatus are the first space 11 for introducing the object to be treated into the classification rotor 1. A cylindrical guide ring (guide plate) 9 which is a guide means for partitioning the object to be processed into a second space 12 for introducing the object to be processed into the dispersion rotor 6.
It is composed of and. The classification rotor 1 and the peripheral portion of the rotor are the classification zones, and the gap portion between the dispersion rotor 6 and the liner 4 is the surface modification zone.

The installation direction of the classification rotor 1 may be not only the vertical type as shown in FIG. 1 but also the horizontal type. Further, the number of the classification rotors 1 is not limited to a single unit as shown in FIG. 1, but may be a plurality.

The toner particles to be subjected to the spheroidizing treatment may be introduced into the first space as shown in FIG. 1 or may be introduced into the second space as shown in FIG. When the toner particles are introduced into the second space, they are introduced into the second space to perform surface modification treatment, then introduced into the first space, classified, and then introduced into the second space again. By circulating the toner particles in the first space and the second space, the classification treatment and the surface modification treatment are repeated to obtain spherical toner particles.

More specifically, the steps of the surface modification treatment and the classification treatment in the surface modification apparatus having the above configuration will be described. When the toner particles are introduced into the second space as in the apparatus of FIG. 3, the discharge valve 8 is used. When a certain amount of toner particles are charged from the raw material supply port 3 in the closed state, the charged toner particles are first sucked by a blower (not shown) and introduced into the second space. The toner particles are guided to the surface modification zone by riding on the circulating flow generated by the dispersion rotor 6 along the inner circumference (second space 12) of the guide ring (guide plate) 9. The toner particles guided to the surface modification zone receive a mechanical impact force between the hammer 10 and the liner 4 of the dispersion rotor 6 and undergo surface modification treatment. The surface-modified surface-modified particles are guided to the classification zone along the outer circumference (first space 11) of the guide ring 9 by the cold air passing through the machine. The surface-modified particles are classified into fine powder having a predetermined particle size or less and coarse powder having a predetermined particle size or more by the classification rotor 1, and the fine powder is discharged to the outside of the machine. It is returned to the space 12 and repeatedly subjected to the surface modification action in the surface modification zone. After a lapse of a certain period of time, the discharge valve 8 is opened, and the spherical toner particles are collected from the powder discharge port 7.

By using a surface modification device that can repeat the surface modification process while discharging and removing fine powder, it is possible to perform the surface modification process in good yield while preventing an increase in the amount of fine powder during surface modification. it can.
Further, by arbitrarily setting the time for opening the discharge valve, the residence time of the toner in the apparatus can be adjusted, the surface shape of the toner particles can be arbitrarily controlled, and the toner particles having a high circularity can be obtained.

The surface shape of the toner particles depends on the residence time of the toner particles in the surface modifier. That is, in order to control the surface shape of the toner particles, it is important to control the circulation time of the toner particles in the surface modifier. In the present invention, the surface modification device used in the surface modification step is a batch type surface modification device as shown in FIG. 1, so that the time until the discharge valve is opened, the tooth shape and rotation of the upper surface of the dispersion rotor are rotated. By controlling the peripheral speed, the distance between the dispersion rotor and the liner, the distance between the guide ring and the dispersion rotor, etc. in an appropriate state, it is possible to prevent the increase of fine powder during surface modification and to prevent the increase of fine powder during surface modification in the toner particle surface modification device. The residence time of the toner can be controlled, and the surface shape of the toner can be arbitrarily controlled. In addition, since it has a built-in classification rotor that classifies surface-modified toner to a predetermined particle size, by controlling the rotational peripheral speed of the classification rotor to an appropriate state, fine powder below the specified particles can be continuously discharged to the outside of the device. Since the coarse powder can be surface-modified again, surface-modified particles from which fine powder has been removed can be obtained.

The circulation time for repeating the surface modification treatment and the classification treatment in the surface modification apparatus is preferably 5 seconds or more, more preferably 10 seconds or more, and the length of the surface modification time is long, from the viewpoint of obtaining the surface modification effect. It is preferably 720 seconds or less, more preferably 600 seconds or less, from the viewpoint of avoiding surface deterioration of the toner due to heat generated during surface modification due to aging, occurrence of in-machine fusion, and deterioration of processing capacity.

From the viewpoint of preventing surface deterioration of toner due to heat generated during surface modification and fusion in the machine, it is preferable to control the temperature inside the device by sending cold air or passing a refrigerant through the jacket. ..

In the present invention, the average circularity is used as an index as an indicator of the degree of sphericalization of the sphericalized toner particles.

The average circularity of the spherical toner particles is preferably 0.945 or more, more preferably 0.955 or more, from the viewpoint of toner durability and transferability. The average circularity is an index showing the degree of unevenness of the toner particles, and the circularity when the toner particles are completely spherical, that is, the upper limit of the average circularity is 1.000. On the other hand, the larger the unevenness of the particle surface, the smaller the value of circularity.

In the present invention, it is preferable to further include a step of mixing the spherical toner particles with the external additive in order to improve the transferability.

Examples of the external additive include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide, and zinc oxide, and organic fine particles such as resin particles such as melamine-based resin fine particles and polytetrafluoroethylene resin fine particles. Two or more types may be used together. Among these, silica is preferable, and from the viewpoint of toner transferability, hydrophobicized silica is more preferable.

Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octylliethoxysilane (OTES), and methyltriethoxysilane. Be done.

The average particle size of the number of external additives is preferably 6 nm or more, more preferably 8 nm or more, and preferably 250 nm or less, more preferably 200 nm or less, from the viewpoint of toner chargeability, fluidity, and transferability. More preferably, it is 150 nm or less.

From the viewpoint of toner chargeability, fluidity, and transferability, the amount of the external additive used is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, based on 100 parts by mass of the spherical toner particles. It is more preferably 0.3 parts by mass or more, and preferably 10 parts by mass or less, more preferably 7 parts by mass or less.

A mixer such as a Henschel mixer can be used for mixing the spherical toner particles with the external additive.

_{The volume median particle diameter (D 50} ) of the toner obtained by the method of the present invention is preferably 3 μm or more, more preferably 4 μm or more, and preferably 15 μm or less, more preferably 10 μm or less. In the present specification, the volume median particle size (D ₅₀ ) means a particle size in which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size. When the toner particles are treated with an external additive, the volume median particle diameter of the toner particles before being treated with the external additive is defined as the volume median particle diameter of the toner.

The toner obtained by the method of the present invention can be used as a one-component developing toner or as a two-component developing agent by mixing with a carrier.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. The physical properties of the resin and the like were measured by the following methods.

[Resin softening point]
Using the flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating a 1 g sample at a heating rate of 6 ° C / min, a load of 1.96 MPa was applied by a plunger, and the diameter was 1 mm and the length was 1 mm. Push out from the nozzle. The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is used as the softening point.

[Maximum peak temperature of endothermic resin]
Using the differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample in an aluminum pan, and 0 at a temperature lowering rate of 10 ° C / min from room temperature. Cool to ° C and hold at 0 ° C for 1 minute. Then, the temperature is measured at a heating rate of 10 ° C./min. Among the observed endothermic peaks, the temperature of the peak on the highest temperature side is defined as the maximum endothermic temperature.

[Resin glass transition temperature]
Using the differential scanning calorimeter "DSC Q20" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample in an aluminum pan, raise the temperature to 200 ° C, and lower the temperature from that temperature. Cool to 0 ° C at a rate of 10 ° C / min. Next, the sample is heated at a heating rate of 10 ° C./min, and the endothermic peak is measured. The temperature at the intersection of the extension of the baseline below the maximum endothermic peak temperature and the tangent line indicating the maximum slope from the rising portion of the peak to the peak of the peak is defined as the glass transition temperature.

[Acid value of resin]
Measure based on the method of JIS K0070. However, only the measurement solvent is changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Melting point of mold release agent]
Using the differential scanning calorimeter "DSC Q20" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample in an aluminum pan, and heat up to 200 ° C at a temperature rise rate of 10 ° C / min. The temperature is raised and cooled from that temperature to -10 ° C at a temperature lowering rate of 5 ° C / min. Next, the sample is heated to 180 ° C. at a heating rate of 10 ° C./min and measured. The maximum peak temperature of the endothermic observed from the melted endothermic curve obtained there is taken as the melting point of the release agent.

[Medium particle size of toner (D ₅₀ ) and content of particles with a particle size of 3 μm or less or 4 μm or less]
Measuring machine: Coulter Multisizer II (manufactured by Beckman Coulter Co., Ltd.)
Aperture diameter: 100 μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (manufactured by Beckman Coulter Co., Ltd.)
Electrolyte: Isoton II (manufactured by Beckman Coulter Co., Ltd.)
Dispersion solution: Emulgen 109P (manufactured by Kao Co., Ltd., polyoxyethylene lauryl ether, HLB (griffin): 13.6) was dissolved in an electrolytic solution to adjust to 5% by mass. Was added and dispersed with an ultrasonic disperser (machine name: US-1, manufactured by SND Co., Ltd., output: 80 W) for 1 minute, then 25 mL of the electrolytic solution was added, and the mixture was further added to the ultrasonic disperser. Disperse for 1 minute to prepare a sample dispersion.
Measurement conditions: To 100 mL of the electrolytic solution, add the sample dispersion so that the particle size of 30,000 particles can be measured in 20 seconds, measure 30,000 particles, and measure the volume from the particle size distribution. The medium particle size (D ₅₀ ) and the content of particles having a particle size of 3 μm or less (3 μm ≧) or 4 μm or less (4 μm ≧) are determined.

[Average circularity of toner]
Measuring machine: FPIA-3000 (manufactured by Sysmex Corporation)
Standard unit (objective lens 10x)
Measurement mode HPF mode Dispersion: Emargen 109P (manufactured by Kao Co., Ltd., polyoxyethylene lauryl ether, HLB13.6) 5% by mass Electrolyte dispersion Condition: Add 10 mg of the measurement sample to 10 ml of the dispersion and use it as an ultrasonic disperser. Disperse for 1 minute, then add 10 ml of distilled water, and further disperse for 2 minutes with an ultrasonic disperser.
Measurement conditions: The circularity of the toner dispersed in the dispersion is measured at 20 ° C. at a concentration of 1800 to 2200 particles, and the number average value is calculated.

[Number of external additives, average particle size]
The particle size (average value of major axis and minor axis) of 500 particles is measured from a scanning electron microscope (SEM) photograph, and the average value thereof is taken as the number average particle size.

Resin production example 1
The raw material monomer and esterification catalyst of the polyester resin other than trimellitic anhydride shown in Table 1 were placed in a 10 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and placed in a nitrogen atmosphere. The temperature was raised to 200 ° C. and the reaction was carried out for 6 hours. After the temperature is further raised to 210 ° C., trimellitic anhydride is added, and the mixture is reacted at normal pressure (101.3 kPa) for 1 hour, and further reacted at 40 kPa until the desired softening point is reached, and the amorphous polyester resin (amorphous polyester resin). Resin A1) was obtained. Table 1 shows the physical characteristics of the obtained resin.

Resin production example 2
The raw material monomer of the polyester resin shown in Table 1 and the esterification catalyst are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and the temperature rises to 235 ° C. under a nitrogen atmosphere. The reaction was carried out by warming until the reaction rate reached 80%, and then the reaction was carried out at 8 kPa until the desired softening point was reached to obtain an amorphous polyester resin (resin A2). Table 1 shows the physical characteristics of the obtained resin. The reaction rate refers to the value of the amount of reaction water produced / the amount of theoretically produced water x 100.

Resin production example 3
The raw material monomer and esterification catalyst of the polyester resin other than trimellitic anhydride shown in Table 1 are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and placed in a nitrogen atmosphere. After the temperature was raised to 230 ° C. and the reaction was carried out for 12 hours, the pressure was reduced to 8.3 kPa and the reaction was carried out for 1 hour. Then, the pressure was returned to normal pressure and the temperature was lowered to 160 ° C., and a mixed solution of the raw material monomer of the styrene resin, the bireactive monomer and the polymerization initiator was added dropwise from the dropping funnel over 1 hour. The addition polymerization reaction was carried out for 1 hour while maintaining the temperature at 160 ° C., the temperature was raised to 210 ° C., and the temperature was maintained at 8.3 kPa for 1 hour. Further, at 210 ° C., trimellitic anhydride was added and reacted until a desired softening point was reached to obtain an amorphous composite resin (resin A3). Table 1 shows the physical characteristics of the obtained resin.

Resin production example 4
The raw material monomer and esterification catalyst of the polyester resin shown in Table 2 are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 130 ° C. in a nitrogen atmosphere. After that, the temperature was raised from 130 ° C. to 200 ° C. over 10 hours, and the temperature was further reduced to 8 kPa while maintaining the temperature at 200 ° C. and reacted for 1 hour to obtain a crystalline polyester resin (resin C1). Table 2 shows the physical characteristics of the obtained resin.

Resin production example 5
The polyester resin raw material monomers and esterification catalysts shown in Table 2 are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 160 ° C. in a nitrogen atmosphere. It was allowed to react for 6 hours. Then, a mixed solution of the raw material monomer of the styrene resin shown in Table 2, the bireactive monomer and the polymerization initiator was added dropwise over 1 hour. After the addition polymerization reaction was carried out for 1 hour while keeping the temperature at 160 ° C., the pressure was reduced to 8.3 kPa and the mixture was held for 1 hour. Further, the temperature was raised to 200 ° C. over 8 hours and reacted at 8.3 kPa for 2 hours to obtain a crystalline composite resin (resin C2). Table 2 shows the physical characteristics of the obtained resin.

Examples 1, 2 and 7 and Comparative Example 1 (Example 1 is a reference example)
The binding resin shown in Table 3 and the negative charge control agent "T-77" (manufactured by Hodogaya Chemical Co., Ltd.) 1.0 part by mass, carbon black "MOGUL-L" (manufactured by Cabot Corporation) 6.0 parts by mass, and release. 5.0 parts by mass of the mold "SP-105" (manufactured by Hiroyuki Kato, Fisher Tropschwax, melting point: 105 ° C.) was stirred and mixed with a Henschel mixer for 1 minute, and then melt-kneaded under the following conditions.

A continuous double open roll type kneader "Kneedex" (manufactured by Mitsui Mining Co., Ltd., roll outer diameter: 14 cm, effective roll length: 80 cm) was used. The operating conditions of the continuous double open roll type kneader are high rotation side roll (front roll) rotation speed 75r / min (peripheral speed 32.97m / min), low rotation side roll (back roll) rotation speed 50r / min ( The peripheral speed was 21.98 m / min), and the roll gap at the end on the side of the kneaded material supply port was 0.1 mm. The heating medium temperature and cooling medium temperature in the roll are 135 ° C on the raw material input side of the high rotation side roll and 90 ° C on the kneaded material discharge side, 35 ° C on the raw material input side of the low rotation side roll and 35 ° C on the kneaded material discharge side. there were. The supply rate of the raw material mixture was 10 kg / h, and the average residence time was about 6 minutes.

The obtained melt-kneaded product was cooled to 20 ° C. or lower while being rolled with a cooling roll, and the cooled melt-kneaded product was roughly pulverized to 3 mm with Rotoplex (manufactured by Toa Kikai Co., Ltd.). Then, fine pulverization was performed using a fluidized bed type jet mill "400 type TFG" (manufactured by Hosokawa Micron Co., Ltd.).

The obtained finely pulverized product was classified using a TTSP classifier (manufactured by Hosokawa Micron Co., Ltd.).

The obtained graded product was modified so that the raw material input port of the surface modifier Faculty "F430 type" (manufactured by Hosokawa Micron) equipped with a hammer and liner was introduced into the second space. Using, the conditions of dispersion rotation speed 5100r / min, classification rotation speed 5200r / min, air volume 20Nm ³ , and 12 hammers are fixed, and the input amount and stirring time are changed to make them spherical so as to have a predetermined circularity. To obtain toner particles.

100 parts by mass of the obtained toner particles, 1.5 parts by mass of hydrophobic silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., average particle size 40 nm), and hydrophobic silica "R972" (manufactured by Nippon Aerosil Co., Ltd.) 0.7 parts by mass (average particle size 16 nm) was mixed with a Henschel mixer for 3 minutes to obtain toner.

Examples 3-5
As raw materials to be used for melt-kneading, the binder resin shown in Table 3, 1.0 part by mass of the negative charge control agent "Bontron E-84" (manufactured by Orient Chemical Co., Ltd.), and the copper phthalocyanine pigment "ECB-301" (Dainichiseika) Except that 5.0 parts by mass of (manufactured by Kogyo Co., Ltd.) and 5.0 parts by mass of mold release agent "SP-105" (manufactured by Hiroyuki Kato, Fisher Tropsch wax, melting point: 105 ° C.) were used, the outside was the same as in Example 1. Toner was obtained by performing the addition treatment.

Example 6
As the release agent, 5.0 parts by mass of "Carnauba Wax No. 1" (manufactured by Hiroyuki Kato, melting point 85 ° C.) was used instead of "SP-105" in the same manner as in Example 3. , Obtained toner.

Example 8
Same as Example 7 except that the same-direction rotating twin-screw extruder "PCM-30" (manufactured by Ikegai Iron Works) was used for melt kneading instead of the continuous double open roll type kneader "Kneedex". Then, the external addition treatment was performed to obtain toner. The operating conditions of the biaxial extruder rotating in the same direction were a barrel set temperature of 100 ° C., a shaft rotation speed of 200 r / min (peripheral speed of shaft rotation 0.30 m / sec), and a mixture supply speed of 10 kg / h.

Comparative Example 2
In the same manner as in Example 1, after rough pulverization using Rotoplex, the fluidized bed type jet mill "400 type TFG" and the surface modifier faculty "F430 type" were not used, and the turbo mill "T-400RS" was used. "(Freund Turbo Co., Ltd.) was used to pulverize and spheroidize. Then, in the same manner as in Example 1, classification and external addition treatment were performed to obtain toner.

Comparative Example 3
In the spheroidization process, instead of the surface modifier faculty "F430 type", a surface modifier "MR-10" (manufactured by Nippon Pneumatic Co., Ltd.) is used, and the temperature and input are adjusted to a predetermined circularity. Toner was obtained by performing an external addition treatment in the same manner as in Example 1 except that the amount was changed to form a sphere.

Comparative Example 4
Toner was obtained in the same manner as in Example 1 except that the spheroidization step was not performed and the classified product was externally added.

Test Example 1 [Low temperature fixability]
Toner is mounted on the non-magnetic one-component developing device "OKI MICROLINE 5400" (manufactured by Oki Data Corporation), the amount of toner adhered ^{is adjusted to 0.50 mg / cm 2} , and a solid image of 20 mm x 30 mm is printed on "Color Copy 90 paper" (Oki Data Corporation). Printed on Fuji Xerox Office Supply Co., Ltd.). A solid image was taken out before passing through the fixing machine to obtain an unfixed image. The paper with the obtained unfixed image was set to 110 ° C and the fixing roll temperature was set to 110 ° C with an external fixing machine modified from the fixing machine of the non-magnetic one-component developing device "OKI MICROLINE 3020c" (manufactured by Oki Data Corporation), and 150 mm. It was fixed at a fixing speed of / sec. After that, the fixing roll temperature was set to 115 ° C., and the same operation was performed. While raising this by 5 ° C., the unfixed image was fixed at each temperature to obtain a fixed image.
Wrap a blank sheet of paper "L paper" (manufactured by Xerox) around a 1000g weight with a bottom surface of 50φ, place this weight on the image part obtained at each fixing temperature, reciprocate 5 times with the width of the image part, and before and after rubbing. Image density was measured using an image density measuring device "SPM-50" (manufactured by Gretag), and the ratio before and after rubbing ([image density after rubbing / image density before rubbing] x 100) was initially 90%. The temperature of the fixing roll exceeding the above was set as the minimum fixing temperature and used as an index of low temperature fixability. The smaller the value, the better the low temperature fixability. The results are shown in Table 3.

Test Example 2 [Durability]
Toner is mounted on the ID cartridge of the non-magnetic one-component developing device "OKI MICROLINE 5400" (manufactured by Oki Data Corporation), and 70r / min (equivalent to 36 sheets / minute) in a low temperature and low humidity (10 ° C, 20%) environment. The development roll surface was visually observed for the occurrence of shavings, and the time until the shavings were generated was measured and used as an index of durability. The larger the value, the better the durability. The results are shown in Table 3.
Note that the sizzle refers to a state in which the amount of toner adhering to the developing roll varies, and the occurrence of the sizzle causes shading in the image density during printing.

From the above results, the toners obtained in Examples 1 to 8 have good low-temperature fixability and durability.
On the other hand, the toner of Comparative Example 1 which does not use the crystalline polyester resin lacks low temperature fixability, and the toners of Comparative Examples 2 to 4 which have not been sphericalized by using a predetermined device have durability. Lack of sex.

The toner obtained by the method of the present invention is suitably used for developing a latent image formed by an electrostatic charge image developing method, an electrostatic recording method, an electrostatic printing method, or the like.

1 Classification rotor 2 Fine powder discharge port 3 Raw material supply port 4 Liner 5 Cold air introduction port 6 Dispersion rotor 7 Powder discharge port 8 Discharge valve 9 Guide ring 10 Hammer 11 First space 12 Second space 13 Casing

Claims (5)

Toners including a spheroidizing step of spheroidizing toner particles containing a crystalline polyester resin and an amorphous polyester resin with a batch type mechanical surface modifier equipped with a hammer and a liner and a classification means. The crystalline polyester-based resin contains an alcohol component containing an aliphatic diol having 9 or more and 14 or less carbon atoms and an aliphatic dicarboxylic acid-based compound having 9 or more and 14 or less carbon atoms. A method for producing a toner, which is a crystalline composite resin containing a polycondensation resin component which is a polycondensation product of and a styrene resin component . The production method according to claim 1, wherein the amorphous polyester resin contains two types of amorphous polyester resins having different softening points. The mass ratio (amorphous polyester resin H / amorphous polyester resin L) of the amorphous polyester resin H having a higher softening point and the amorphous polyester resin L having a lower softening point is 5 The manufacturing method according to claim 2, wherein it is / 95 or more and 45/55 or less. The pulverization step includes a step of obtaining toner particles by a method including a kneading step of melt-kneading a composition containing a crystalline polyester resin and an amorphous polyester resin and a pulverization step of pulverizing the obtained kneaded product. The production method according to any one of claims 1 to 3 , wherein the kneaded product is pulverized by a jet mill. A batch type surface modifier continuously discharges and removes fine powder to the outside of the apparatus, a surface treatment means equipped with a hammer and a liner, and a first space and a cover for introducing an object to be treated into the classification means. The manufacturing method according to any one of claims 1 to 4, wherein the apparatus has a guiding means for partitioning the inside of the apparatus with a second space for introducing the processed material into the surface treatment means.

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