JP2019204031A - Binder resin composition for toner - Google Patents

Abstract

To provide a binder resin composition with which a toner excellent in fixability to a polypropylene film and fixability to a polyethylene terephthalate film is obtained, and a toner for electrostatic charge image development containing the binder resin composition.SOLUTION: There are provided (1) a binder resin composition for a toner that contains an amorphous polyester resin A, wherein the amorphous polyester resin A has a constitutional part derived from a polyester resin, and a constitutional part derived from a modified polypropylene polymer A having a carboxylic acid group or a carboxylic acid anhydride group; the constitutional part derived from the polyester resin and the constitutional part derived from the modified polypropylene polymer A are bonded through covalent bond; the polymer A is a polypropylene polymer modified by a carboxylic acid compound having an unsaturated bond or an anhydride thereof; the ester group concentration of the constitutional part derived from a polyester resin in the amorphous polyester resin A is 6 mmol/g or more, and (2) a toner for electrostatic charge image development containing the binder resin composition according to (1).SELECTED DRAWING: None

Description

  The present invention relates to a binder resin composition for toner, an electrostatic charge image developing toner containing the binder resin composition, and the like.

In the field of electrophotography, with development of an electrophotographic system, development of a toner for developing an electrostatic image corresponding to high image quality and high speed printing is required.
For example, Patent Document 1 describes a toner binder resin composition containing a polyester resin containing as a constituent unit a compound (X) that satisfies the following conditions (i) to (iii).
(I) The number of functional groups (f) capable of reacting with an acid or alcohol is 1.0 (mmol / g) or more.
(Ii) including a branched long-chain alkyl group (r) having 30 or more carbon atoms.
(Iii) The endothermic amount upon melting is 100 (J / g) or less.
Thus, it is described that a toner having good fixing performance, non-offset property, image stability and durability and a binder resin composition for toner are provided.

Patent Document 2 contains a polyester-based resin and a polypropylene-based wax (W-1). Formula (1): endothermic ratio ΔH _{CW / W} = ΔH _CW / ΔH _W (1) (ΔH _CW : Endothermic amount of melting endothermic peak per 1 g of polypropylene wax (W-1) when measured as a resin composition, ΔH _W : Polypropylene wax when measured alone with polypropylene wax (W-1) (W-1) The endothermic amount ratio ΔH _{CW / W} expressed by (endothermic amount of melt endothermic peak per gram) is 0.10 or more and 0.80 or less, and the binder resin composition for electrostatic charge image developing toner is described. . It is described that the binder resin composition can provide a binder resin composition for an electrostatic charge image developing toner and the like that can obtain a toner excellent in fixability to a PP film.

JP 2009-14820 International Publication WO2016 / 186129

On the other hand, with the diversification of print media, electrophotographic printing on print media other than paper has begun to be demanded. One of the main media is polypropylene film (hereinafter also referred to as “PP film”), which is used for PET bottle labels and various packages. On the other hand, paper and polypropylene have greatly different characteristics as printing media, such as the polarity of the material and the state of the surface. Therefore, for example, the conventionally developed toner described in Patent Document 1 has a problem that it does not fix to the PP film.
Further, in the toner disclosed in Patent Document 2, since the polypropylene resin dispersed in a very fine size is contained in the binder resin, further improvement has been desired from the viewpoint of stability and manufacturability.
From the viewpoint of diversification of printing media, printing on polyethylene terephthalate film (hereinafter also referred to as “PET film”) is also required. Polypropylene and polyethylene terephthalate also have greatly different print media characteristics such as material polarity and surface condition. Therefore, a toner capable of printing on various print media is required.
The present invention relates to a binder resin composition from which a toner excellent in fixability to a polypropylene film and fixability to a polyethylene terephthalate film can be obtained, and an electrostatic charge image developing toner containing the binder resin composition.

The present invention relates to the following [1] to [2].
[1] A binder resin composition for toner containing amorphous polyester resin A,
The amorphous polyester resin A has a constituent part derived from a polyester resin and a constituent part derived from a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group, and a constituent part derived from the polyester resin. And the component part derived from the modified polypropylene polymer A are linked via a covalent bond,
The polymer A is a polypropylene polymer modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof,
A binder resin composition for toner, wherein an ester group concentration of a constituent site derived from the polyester resin of the amorphous polyester resin A is 6 mmol / g or more.
[2] An electrostatic charge image developing toner comprising the binder resin composition according to [1].

  According to the present invention, a binder resin composition from which a toner excellent in fixability to a polypropylene film and fixability to a polyethylene terephthalate film can be obtained, and an electrostatic charge image developing toner containing the binder resin composition, etc. Can be provided.

[Binder resin composition]
The binder resin composition for toner according to an embodiment of the present invention (hereinafter also simply referred to as “binder resin composition”) contains amorphous polyester resin A.
The amorphous polyester resin A has a constituent part derived from a polyester resin and a constituent part derived from a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group.
And the structural site derived from the polyester resin and the structural site derived from the modified polypropylene polymer A are linked via a covalent bond.
In addition, the polymer A is a polypropylene polymer modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof.
Furthermore, the ester group density | concentration of the structural site derived from the polyester resin of the amorphous polyester-type resin A is 6 mmol / g or more.

The reason why an electrostatic charge image developing toner (hereinafter, also simply referred to as “toner”) having excellent fixability to a PP film and fixability to a PET film can be obtained by the binder resin composition according to an embodiment is obvious. Although not, it is thought as follows.
The binder resin composition according to an embodiment contains a polyester resin A having a constituent part derived from a polyester resin and a constituent part derived from a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group. . The constituent part derived from the polyester resin and the constituent part derived from the polymer A are linked via a covalent bond and have a structure in which they are combined at the molecular level. Then, due to the fixing heating when printing on the PP film by electrophotography, the constituent part derived from the polymer A of the polyester resin A is oriented in the PP film direction, and the intermolecular interaction between the PP film and the polyester resin. It is considered that the fixability to the PP film can be achieved by the expression of.
In addition, the binder resin composition according to one embodiment has an ester group concentration of 6 mmol / g or more in the component part derived from the polyester resin of the amorphous polyester resin A, and the ester group concentration is relatively high. High polarity. Then, by fixing heating when printing on the PET film by electrophotography, the constituent part derived from the polyester resin of the polyester resin A is oriented in the direction of the PET film, and intermolecular interaction occurs between the PET film and the polyester resin. By exhibiting, it is considered that the fixing property to the PET film can be achieved.

Definitions of various terms and the like in this specification are shown below.
Whether the resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is the ratio between the softening point of the resin and the highest endothermic peak temperature derived from the polyester constituent site (softening point (° C) / highest endothermic peak temperature (° C)) in the measurement methods described in the examples below. ). The crystalline resin is a resin having a crystallinity index of 0.65 or more and less than 1.4, preferably 0.7 or more, more preferably 0.9 or more, and preferably 1.2 or less. An amorphous resin is a resin having a crystallinity index of 1.4 or more or less than 0.65. The crystallinity index can be appropriately adjusted according to the production conditions such as the type and ratio of the raw material monomers, the reaction temperature, the reaction time, and the cooling rate. Although the peak derived from the polyester resin constituent site can be assigned by a conventional method, it usually appears on the lower temperature side than the endothermic peak derived from the constituent site derived from the modified polypropylene polymer A. When it is unclear which peak should be attributed, the polyester resin alone and the modified polypropylene polymer A alone are measured under the above conditions using a differential scanning calorimeter. An endothermic peak is attributed to an endothermic peak derived from each constituent site.
“Carboxylic acid compound” includes not only the carboxylic acid but also an anhydride that decomposes during the reaction to produce an acid, and an alkyl ester of the carboxylic acid (for example, an alkyl group having 1 to 3 carbon atoms). It is.
When the carboxylic acid compound is an alkyl ester of carboxylic acid, the carbon number of the carboxylic acid compound does not include the carbon number of the alkyl group that is the alcohol residue of the ester.
The “binder resin” means a resin component contained in the toner including the polyester resin A.

<Polyester resin A>
The polyester resin A has, for example, a constituent part derived from a polyester resin and a constituent part derived from the modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group, and the constituent part derived from the polyester resin and the modified polypropylene. A polyester resin that is linked to a constituent site derived from the polymer A via a covalent bond, and a polyester resin that has been modified to such an extent that its properties are not substantially impaired. Examples of the modified polyester resin include a urethane-modified polyester resin in which a constituent site derived from a polyester resin is modified with a urethane bond, and an epoxy-modified polyester resin in which a constituent site derived from a polyester resin is modified with an epoxy bond. It is done.
The constituent site derived from the polyester resin and the constituent site derived from the addition polymerization resin are linked via a covalent bond.
Being linked via a covalent bond means that the constituent parts are linked via a covalent bond.
Examples where the constituent sites are linked via a covalent bond include, for example, an ester bond, an ether bond, an amide bond, a urethane bond, and a bond having these bonds and a linking group.
Examples of the linking group include divalent or higher hydrocarbon groups having 1 to 6 carbon atoms. Examples of the linking group include a methylene group, an ethylene group, a propylene group, and a phenyl group.
Especially, it is preferable to connect through an ester bond, and it is more preferable to connect directly with an ester bond.

[Ester group concentration]
The ester group concentration (hereinafter also simply referred to as “ester group concentration”) of the constituent part derived from the polyester resin of the amorphous polyester resin A is 6 mmol / g from the viewpoint of obtaining a toner having excellent fixability to a PET film. That's it.
The ester group concentration is preferably 7 mmol / g or more, more preferably 8 mmol / g or more, and preferably 15 mmol / g or less, more preferably from the viewpoint of further improving the fixability to the PET film. It is 13 mmol / g or less, More preferably, it is 11 mmol / g or less.
The ester group concentration of the constituent part derived from the polyester resin of the amorphous polyester resin A is calculated by the following equation.

[In the formula, A is the total ester bond amount (mol) produced when all of the raw material monomer (E) of the polyester resin is reacted, and B is the total mass (g of raw material monomer (E) of the constituent site derived from the polyester resin) ). In addition, the inside of () in a formula means the unit of each numerical value. ]

[Component parts derived from polyester resin]
Hereinafter, the structural part derived from the polyester resin will be described.
The “constituent part derived from the polyester resin” means a constituent part of the resin in which a part of the polyester resin is bonded to other molecular groups.
The polyester resin is, for example, a polycondensate of an alcohol component and a carboxylic acid component.
The alcohol component is preferably an aliphatic alcohol having 2 to 6 carbon atoms from the viewpoint of obtaining a toner excellent in fixability to a PET film.
The carbon number of the aliphatic alcohol is preferably 2 or more and 4 or less, more preferably 2 or 3.
Examples of the aliphatic alcohol having 2 to 6 carbon atoms include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol is mentioned. Among these, ethylene glycol, 1,2-propanediol, and neopentyl glycol are preferable, and ethylene glycol and 1,2-propanediol are more preferable. A combination of ethylene glycol and 1,2-propanediol is more preferred.
The content of the aliphatic alcohol having 2 to 6 carbon atoms is preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, and still more preferably 95 mol% or more in the alcohol component. And 100 mol% or less, more preferably 100 mol%.

Examples of other alcohol components include aliphatic diols having 7 or more carbon atoms such as 1,8-octanediol, polyoxypropylene adducts of 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis Examples include aromatic diols such as polyoxyethylene adducts of (4-hydroxyphenyl) propane and trihydric or higher alcohols such as glycerin.
The content of other alcohol components is preferably 30 mol% or less, more preferably 20 mol% or less, and still more preferably 10 mol% or less.

Examples of the carboxylic acid component include aromatic dicarboxylic acid compounds, aliphatic dicarboxylic acid compounds, and trivalent or higher carboxylic acid compounds.
Among these, the carboxylic acid component preferably contains an aromatic dicarboxylic acid compound.
Examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, and terephthalic acid. Among these, from the viewpoint of low-temperature fixability, at least one selected from terephthalic acid and isophthalic acid is more preferable, and terephthalic acid is more preferable.
The content of the aromatic dicarboxylic acid compound is preferably 20 mol% or more, more preferably 40 mol% or more, still more preferably 60 mol% or more, and still more preferably 80 mol% from the viewpoint of low-temperature fixability in the carboxylic acid component. % Or more, and 100 mol% or less, and preferably 100 mol%.

Examples of other carboxylic acid components include aliphatic dicarboxylic acids.
Examples of the aliphatic dicarboxylic acid compound include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, an alkyl group having 1 to 20 carbon atoms, or an alkenyl group having 2 to 20 carbon atoms. And aliphatic dicarboxylic acids such as succinic acid and adipic acid which may be substituted with.
Succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms is preferably succinic acid substituted with an alkyl group or alkenyl group having 6 to 14 carbon atoms, More preferred is succinic acid substituted with an alkyl group or alkenyl group having 8 to 12 carbon atoms. Specific examples include octyl succinic acid and dodecenyl succinic acid (tetrapropenyl succinic acid).
Among these, fumaric acid is preferable.
The content of the aliphatic dicarboxylic acid compound is preferably 30 mol% or less, more preferably 20 mol% or less, and still more preferably 10 mol% or less in the carboxylic acid component.

Examples of the trivalent or higher carboxylic acid compound include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Mellitic acid or acid anhydride thereof (hereinafter also referred to as “trimellitic acid compound”) is preferable.
The content of the trivalent or higher carboxylic acid compound is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 12 mol% or more, from the viewpoint of low-temperature fixability in the carboxylic acid component, and Preferably, it is at most 50 mol%, more preferably at most 40 mol%, still more preferably at most 30 mol%.
The alcohol component may contain a monovalent alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound as appropriate.

The ratio of the carboxyl group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group / OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, more preferably 1.2 or less. .
From the viewpoint of increasing the softening point of the resulting polyester resin, the equivalent ratio of COOH groups to OH groups in the raw materials of the polyester resin (alcohol component and carboxylic acid component) is excessive (the above ratio [COOH group / OH group] Is preferably greater than 1.0). Further, from the viewpoint of lowering the softening point of the obtained polyester resin, it is preferable that the OH group is excessive (the ratio [COOH group / OH group] is less than 1.0).

[Polymer A]
The polyester-based resin A is a component derived from the modified polypropylene-based polymer A having a carboxylic acid group or a carboxylic anhydride group from the viewpoint of obtaining a toner having excellent fixability to PP film, storage stability, and chargeability. Have.
The polymer A is a polypropylene polymer modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof from the viewpoint of excellent fixability to PP film, storage stability, and chargeability. (Hereinafter also referred to as “acid-modified polypropylene polymer”).

Examples of the polypropylene-based polymer before modification include polypropylene and a copolymer of propylene and other olefins.
Polypropylene is, for example, a method obtained by polymerization of general propylene, a method obtained by thermally decomposing polypropylene used for general molding containers, and the like, and is produced as a by-product during the production of polypropylene used for general molding containers. And polypropylene obtained by a method of separating and purifying low molecular weight polypropylene.
Examples of the copolymer of propylene and other olefins include copolymers obtained by polymerizing propylene and other olefins having an unsaturated bond copolymerizable with propylene. The copolymer may be either a random copolymer or a block copolymer.
Examples of other olefins include ethylene and olefins having 4 to 10 carbon atoms. Examples of other olefins include ethylene, butene, pentene, hexene, and 2-ethylhexene.

Examples of the acid-modified polypropylene polymer include a polypropylene polymer terminal-modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof (hereinafter also simply referred to as “terminal-modified polypropylene polymer”), unsaturated. Examples thereof include a polypropylene polymer obtained by random graft modification of a carboxylic acid compound having a bond or an anhydride thereof (hereinafter also simply referred to as “random graft modified polypropylene polymer”).
Among these, a polypropylene polymer terminal-modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof is preferable. The terminal-modified polypropylene polymer is preferably a polypropylene polymer modified with a carboxylic acid compound having an unsaturated bond only at one end or its anhydride (hereinafter referred to as “one-end-modified polypropylene polymer”). Say).
Examples of the carboxylic acid compound having an unsaturated bond or an anhydride thereof include maleic anhydride, fumaric acid, and itaconic acid. Of these, maleic anhydride is preferred.
Examples of the polypropylene polymer terminal-modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof include, for example, a polypropylene polymer having an unsaturated bond at the terminal, a carboxylic acid compound having an unsaturated bond or an anhydride thereof. It can be obtained by subjecting a product to an En reaction. The one-end-modified polypropylene polymer can be obtained, for example, by subjecting a polypropylene polymer having an unsaturated bond at one end to a carboxylic acid compound having an unsaturated bond or its anhydride. A polypropylene polymer having an unsaturated bond at one end can be obtained by a known method, and can be produced using, for example, a vanadium catalyst, a titanium catalyst, a zirconium catalyst or the like.

Examples of the polymer A include terminal maleic anhydride-modified polypropylene, and copolymers of terminal maleic anhydride-modified propylene and other olefins.
Among these, from the viewpoint of improving fixability to polypropylene film, storage stability, and chargeability, terminal-maleic anhydride-modified polypropylene is preferable, and one-terminal maleic anhydride-modified polypropylene is more preferable. By introducing a maleic anhydride site into the polypropylene polymer, the constituent sites derived from the two polyester resins can be linked via an ester bond. In particular, by using a one-terminal maleic anhydride-modified polypropylene polymer, a polyester resin having a structure in which constituent parts derived from two polyester resins are linked by a maleic anhydride moiety at the terminal of the polypropylene polymer is obtained. it is conceivable that. Therefore, it is considered that by using a one-terminal maleic anhydride-modified polypropylene-based polymer, the fixability to a polypropylene film can be further improved, and the storability and chargeability of the toner can be further improved.

  Examples of commercially available end-modified polypropylene-based polymers include one-end maleic anhydride-modified polypropylene “X-10065” (Mn = 1,000), one-end maleic anhydride-modified polypropylene “X-10088” (Mn = 2,500), One-end maleic anhydride-modified polypropylene “X-10082” (Mn = 8,000), One-end maleic anhydride-modified propylene / hexene copolymer “X-10087” (Mn = 800), One-end maleic anhydride-modified propylene / hexene Examples thereof include a copolymer “X-10053” (Mn = 2,000) and a one-terminal maleic anhydride-modified propylene / hexene copolymer “X-10052” (Mn = 4,000) (manufactured by BAKER HUGHES).

The random graft-modified polypropylene polymer is preferably a polypropylene polymer in which maleic anhydride is randomly grafted and modified (hereinafter also referred to as “random graft maleic anhydride-modified polypropylene polymer”).
The random graft maleic anhydride-modified polypropylene polymer is preferably modified by grafting one or more maleic anhydrides in one molecule. Whether it is modified by maleic anhydride can be defined by general spectral measurement. When modified with maleic anhydride, the double bond of maleic anhydride changes to a single bond, which can be defined by measuring the spectral change.
The random graft-modified polypropylene polymer can be obtained, for example, by generating a radical in the polypropylene polymer molecule and reacting with a carboxylic acid compound having an unsaturated bond or an anhydride thereof.

  Commercially available products of random graft modified polypropylene polymers include, for example, random graft maleic anhydride modified polypropylene polymers such as “M-100”, “M-300”, “M-310” of “TOYO-TAC” series. ", PMA H1000A", "PMA H1100A", "PMA H3000A", "PMA-T", "PMA-F2", "PMA-L" (above, manufactured by Toyobo Co., Ltd.), "UMEX" series "1001" ”,“ 1010 ”,“ 100TS ”,“ 110TS ”(above, manufactured by Sanyo Chemical Industries, Ltd.),“ 003 ”,“ 006 ”(above, manufactured by Akzo Nobel Co., Ltd.) of“ Kayabrit ”series.

  The melting point of the polymer A is preferably 10 ° C. or higher, more preferably 20 ° C. or higher, further preferably 40 ° C. or higher, more preferably 60 ° C. or higher, more preferably, from the viewpoint of further improving the fixability to the PP film. 70 ° C or higher, more preferably 80 ° C or higher, and preferably 170 ° C or lower, more preferably 150 ° C or lower, still more preferably 140 ° C or lower, still more preferably 120 ° C or lower, still more preferably 100 ° C or lower. .

  The acid value of the polymer A is preferably 200 mgKOH / g or less, more preferably 150 mgKOH / g or less, further preferably 100 mgKOH / g or less, more preferably 80 mgKOH / g, from the viewpoint of further improving the fixability to PP film. And preferably 0.1 mgKOH / g or more, more preferably 1 mgKOH / g or more, still more preferably 5 mgKOH / g or more, and further preferably 10 mgKOH / g or more.

The hydroxyl value of the polymer A is preferably 70 mgKOH / g or less, more preferably 30 mgKOH / g or less, still more preferably 10 mgKOH / g or less, and 0 mgKOH / g from the viewpoint of further improving the fixability to the PP film. g or more, preferably 0 mg KOH / g.
The measuring method of melting | fusing point, an acid value, and a hydroxyl value is based on the method as described in an Example.

The number average molecular weight of the polymer A is preferably 300 or more, more preferably 500 or more, further preferably 700 or more, more preferably 1,000 or more, and preferably from the viewpoint of further improving the fixability to the PP film. Is 50,000 or less, more preferably 15,000 or less, still more preferably 8,000 or less, still more preferably 4,000 or less, and still more preferably 3,000 or less.
The number average molecular weight is measured by gel permeation chromatography using polystyrene as a standard sample.

In the polyester resin A, the amount of the constituent part derived from the polymer A is preferably 3% from the viewpoint of improving fixability to polypropylene film, storage stability, and chargeability, and increasing toner productivity. % Or more, more preferably 5% by mass or more, still more preferably 8% by mass or more, and from the viewpoint of fixability to PP film, it is preferably 40% by mass or less, more preferably 30% by mass or less, and still more preferably 25%. It is not more than mass%, more preferably not more than 15 mass%.
In the above amount, the amount of the polyester resin A is the total amount of the polymer A and the raw material monomer, and is an amount excluding the amount of dehydration by polycondensation.

[Method for Producing Binder Resin Composition Containing Polyester Resin A]
The binder resin composition contains a polyester resin A.
The polyester resin A is, for example,
(A) a method comprising polycondensing a raw material monomer containing an alcohol component and a carboxylic acid component in the presence of a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group, or (b) a polyester resin , Or a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group.
Examples of the reaction (b) include dehydration condensation and transesterification. The reaction conditions are preferably such that the carboxylic acid group or carboxylic anhydride group of the polymer A and the alcohol component, carboxylic acid component, etc. are dehydrated or transesterified.

  The polycondensation of the alcohol component and the carboxylic acid component is performed at a temperature of about 180 ° C. or higher and 250 ° C. or lower in the presence of an esterification catalyst, a polymerization inhibitor, or the like, if necessary, in an inert gas atmosphere. Can do. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropylate bistriethanolamate. Examples of the esterification cocatalyst that can be used together with the esterification catalyst include gallic acid and the like. The amount of esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1 part by mass or less, with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.8 mass part or less. The amount of esterification cocatalyst used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less.

[Physical properties of polyester resin A]
The softening point of the polyester-based resin A is preferably 80 ° C. or higher, more preferably 85 ° C. or higher from the viewpoint of further improving the storage stability, and preferably 170 ° C. or lower from the viewpoint of further improving the low-temperature fixability. More preferably, it is 150 ° C. or less, and further preferably 120 ° C. or less.

  The glass transition temperature of the polyester-based resin A is preferably 40 ° C. or higher, more preferably 50 ° C. or higher from the viewpoint of further improving the storage stability, and preferably 80 ° C. from the viewpoint of further improving the low-temperature fixability. Hereinafter, it is more preferably 70 ° C. or less, further preferably 60 ° C. or less, and further preferably 58 ° C. or less.

  According to the binder resin composition according to one embodiment, a toner having excellent fixability to a PP film and fixability to a PET film can be obtained. Therefore, it is used as a binder resin composition for polypropylene film printing toner.

[toner]
The toner contains the above-described binder resin composition. According to the binder resin composition, since a toner excellent in fixability to a polypropylene film can be obtained, a polypropylene film printing toner is provided. That is, it is used as an electrostatic charge developing toner for polypropylene film printing.

  From the viewpoint of further improving the low-temperature fixability, the toner preferably contains two or more polyester resins having a softening point of 15 ° C. or more, and more preferably at least one is the above-described polyester resin A. When either one is the polyester resin A, the polyester resin having a low softening point is more preferably the polyester resin A from the viewpoint of further improving the PP film fixing property.

  The softening point of the polyester resin H having the higher softening point (hereinafter also simply referred to as “resin H”) is preferably 110 ° C. or higher, more preferably 130 ° C. or higher, from the viewpoint of further improving the hot offset resistance. In view of further improving the low-temperature fixability, it is preferably 170 ° C. or lower, more preferably 150 ° C. or lower.

  The softening point of the polyester resin L having a lower softening point (hereinafter also simply referred to as “resin L”) is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, from the viewpoint of further improving the hot offset resistance. In view of further improving the low-temperature fixability, it is preferably 120 ° C. or lower, more preferably 110 ° C. or lower.

  The difference in softening point between the resin H and the resin L is preferably 15 ° C. or more, more preferably 20 ° C. or more, from the viewpoint of further improving the low temperature fixability, and preferably from the viewpoint of further improving the low temperature fixability. Is 60 ° C. or lower, more preferably 50 ° C. or lower.

  The softening point of the polyester resin can be adjusted by the degree of crosslinking and the like. From this viewpoint, the resin H contains a trivalent or higher carboxylic acid compound as the carboxylic acid component. The content of the trivalent or higher carboxylic acid compound in the carboxylic acid component is preferably 10 mol% or more, more preferably 15 mol% or more, and preferably 35 mol from the viewpoint of further improving the low-temperature fixability. % Or less, more preferably 30 mol% or less.

  On the other hand, from the viewpoint of further improving the hot offset resistance, the resin L preferably contains a trivalent or higher carboxylic acid compound, and the content of the trimellitic acid compound in the carboxylic acid component is low-temperature fixing. From the viewpoint of further improving the properties, it is preferably 10 mol% or less, more preferably 8 mol% or less, still more preferably 5 mol% or less, still more preferably 3 mol% or less, and 0 mol%.

  The mass ratio of resin H to resin L (resin H / resin L) is preferably 20/80 or more, more preferably 30/70 or more, and even more preferably 40/60 or more, from the viewpoint of further improving hot offset resistance. In view of further improving the low-temperature fixability, it is preferably 90/10 or less, more preferably 80/20 or less, and still more preferably 70/30 or less.

  The content of the polyester-based resin A is preferably 20% by mass or more, more preferably 30% in the binder resin from the viewpoint of further improving the fixability to PP film, storage stability, printing durability, and offset resistance. It is at least mass%, more preferably at least 40 mass%, and preferably at most 80 mass%, more preferably at most 70 mass%, still more preferably at most 60 mass%.

  For example, a colorant, a release agent, a charge control agent, a magnetic powder, a fluidity improver, a conductivity modifier, a reinforcing filler such as a fibrous substance, an antioxidant, and a cleaning property improver are added to the toner. An agent may be contained, and a colorant, a release agent and a charge control agent are preferably contained.

<Colorant>
As the colorant, all of dyes and pigments used as toner colorants can be used, such as carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow and the like can be used, and the toner 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. Part or less, more preferably 20 parts by weight or less, more preferably 10 parts by weight or less.

<Release agent>
Examples of the release agent include polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax; aliphatic hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, sazol wax, or oxides thereof; Uwa wax, montan wax or ester waxes such as deoxidized wax and fatty acid ester wax; fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts, and the like. These may be used alone or in combination of two or more. Can be used.

  The melting point of the release agent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher from the viewpoint of further improving the hot offset resistance of the toner, and preferably 160 ° C. from the viewpoint of further improving the low-temperature fixability. ° C or lower, more preferably 140 ° C or lower, still more preferably 120 ° C or lower, still more preferably 110 ° C or lower.

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

<Charge control agent>
The charge control agent may be either a positive charge control agent or a negative charge control agent.
Examples of positively chargeable charge control agents include nigrosine dyes such as “Nigrosine Base EX”, “Oil Black BS”, “Oil Black SO”, “Bontron N-01”, “Bontron N-04”, “Bontron N-07 ”,“ Bontron N-09 ”,“ Bontron N-11 ”(manufactured by Orient Chemical Industry Co., Ltd.), etc .; triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as“ Bontron P-51 "(manufactured by Orient Chemical Co., Ltd.), cetyltrimethylammonium bromide," COPY CHARGE PX VP435 "(manufactured by Clariant Co., Ltd.), etc .; Imidazole derivatives such as “PLZ-2001”, “PLZ-8001” (manufactured by Shikoku Kasei Kogyo Co., Ltd.) and the like; styrene-acrylic resins such as “FCA-701PT” (Fujikura Kasei Co., Ltd.); For example).

  In addition, as the negatively chargeable charge control agent, metal-containing azo dyes such as “Varifast Black 3804”, “Bontron S-31”, “Bontron S-32”, “Bontron S-34”, “Bontron S-36” (Above, manufactured by Orient Chemical Co., Ltd.), “Eisenspiron Black TRH”, “T-77” (above, manufactured by Hodogaya Chemical Co., Ltd.), etc .; metal compounds of benzylic acid compounds such as “LR- 147 "," LR-297 "(manufactured by Nippon Carlit Co., Ltd.), etc .; metal compounds of salicylic acid compounds, such as" Bontron E-81 "," Bontron E-84 "," Bontron E-88 "," Bontron " "E-304" (made by Orient Chemical Co., Ltd.), "TN-105" (made by Hodogaya Chemical Co., Ltd.), etc .; copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE NX VP434" (Clariant) Product), Nitroimidazole Derivatives and the like; organometallic compounds and the like.

  The content of the charge control agent is preferably 0.01 parts by mass or more, more preferably 0.2 parts 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. Part or less, more preferably 5 parts by weight or less, still more preferably 3 parts by weight or less, and still more preferably 2 parts by weight or less.

[Toner Production Method]
The toner may be a toner obtained by any known method such as a melt-kneading method, an emulsion phase inversion method, a polymerization method, and an agglomeration fusion method, but from the viewpoint of productivity and dispersibility of the colorant, A pulverized toner obtained by a melt kneading method is preferred. In the case of pulverized toner by the melt-kneading method, for example, a raw material such as a binder resin, a colorant, a release agent, and a charge control agent is uniformly mixed with a mixer such as a Henschel mixer, and then a sealed kneader, uniaxial or biaxial It can be manufactured by melt-kneading with a shaft extruder, open roll type kneader or the like, cooling, pulverizing and classifying.

The volume median particle size (D ₅₀ ) of the toner particles 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 at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size.

An external additive is preferably used for the toner in order to improve the storage stability. 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 resin fine particles and polytetrafluoroethylene resin fine particles. These may be used alone or in combination of two or more.
Examples of the silica include hydrophobic silica that has been subjected to a hydrophobic treatment.
Examples of the hydrophobizing agent for hydrophobizing the surface of silica fine particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. Can be mentioned. One or more of these may be used.
Among these, silica is preferable, and hydrophobic silica subjected to hydrophobic treatment is more preferable from the viewpoint of toner transferability.
The average particle diameter of the external additive is preferably 10 nm or more, more preferably 15 nm or more, and preferably 250 nm or less, more preferably 200 nm or less, from the viewpoint of chargeability, fluidity, and transferability of the toner. Preferably it is 150 nm or less, More preferably, it is 90 nm or less.

  The content of the external additive is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass with respect to 100 parts by mass of the toner before being processed with the external additive, from the viewpoint of chargeability, fluidity, and transferability of the toner. Part or more, more preferably 0.3 part by weight or more, and preferably 5 parts by weight or less, more preferably 3 parts by weight or less.

  The toner can be used as a one-component developing toner or as a two-component developer mixed with a carrier.

[Printing on PP film]
Printing on a PP film using toner is performed using a normal electrophotographic system.
Examples of the PP film include an untreated biaxially stretched PP film, a corona-treated PP film, a chemically treated PP film, a plasma-treated PP film, and a stretched film of a composite resin of PP and other resins and additives. From the viewpoint of cost, an untreated biaxially stretched PP film and a corona-treated PP film are preferable.
As the fixing temperature of the binder resin, it is preferable to set the fixing temperature to be equal to or higher than the melting point of the polymer A from the viewpoint of effectively generating an interaction between the polymer A and the PP film.

  In the electrophotographic method, the fixing temperature is preferably 180 ° C. or lower, more preferably 160 ° C. or lower, more preferably 140 ° C. or lower, from the viewpoint of heat resistance of the PP film, and preferably from the viewpoint of fixing properties. It is 70 ° C or higher, more preferably 80 ° C or higher, and still more preferably 90 ° C or higher.

  Each property was measured by the following method.

[Measuring method]
[Melting point of polymer A (Mp)]
Using a differential scanning calorimeter “DSC210” (manufactured by Seiko Instruments Inc.), the sample was heated to 200 ° C and cooled to 0 ° C at a temperature decrease rate of 10 ° C / min. Raise the temperature. The maximum peak temperature of heat of fusion is taken as the melting point.

[Acid Value of Binder Resin, Polyester Resin A, and Polymer A]
Measured according to the method of JIS K 0070: 1992. However, only the measurement solvent was changed from a mixed solvent of ethanol and ether specified in JIS K 0070: 1992 to a mixed solvent of chloroform and dimethylformamide (hereinafter also referred to as “DMF”) (chloroform: DMF = 7: 3 (volume ratio)). change.

[Softening point, maximum peak temperature, and glass transition temperature of binder resin, polyester resin A, and polymer A]
(1) Softening point Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), a 1 g sample was heated at a heating rate of 6 ° C./min. Extrude from a 1mm long 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 taken as the softening point.
(2) Maximum endothermic peak temperature of the constituent parts derived from polyester resin Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), the temperature drop rate from room temperature (20 ° C.) to 10 ° C. / The sample cooled to 0 ° C. for 1 minute is held for 1 minute as it is, and then measured while the temperature is raised to 180 ° C. at a heating rate of 10 ° C./min. Of the endothermic peaks derived from the constituent parts derived from the polyester resin, the peak temperature appearing on the highest temperature side is defined as the highest endothermic peak temperature.
Although the peak of the constituent site derived from the polyester resin can be attributed from a conventional method, it usually appears on the lower temperature side than the endothermic peak derived from the constituent site derived from the modified polypropylene polymer A. When it is unclear which peak should be attributed, the polyester resin alone and the modified polypropylene polymer A alone are measured under the above conditions using a differential scanning calorimeter. An endothermic peak is attributed to an endothermic peak derived from each constituent site.
(3) Glass transition temperature Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of a sample is weighed into an aluminum pan and heated to 200 ° C. Cool from temperature to 0 ° C at a temperature drop rate of 10 ° C / min. Next, measurement is performed while the temperature is increased to 150 ° C. at a temperature increase rate of 10 ° C./min.
The glass transition temperature is defined as the temperature at the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent line indicating the maximum slope from the peak rising portion to the peak apex.

[Volume-median particle diameter of toner particles (D ₅₀ )]
The volume median particle size (D ₅₀ ) of the toner particles is measured by the following method.
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 50μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen “109P” (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) 5% by weight electrolyte Dispersion condition: Add 10 mg of measurement sample to 5 mL of dispersion and use ultrasonic disperser for 1 minute Disperse, and then add 25 mL of electrolyte, and further disperse for 1 minute with an ultrasonic disperser.
Measurement conditions: 100 mL of electrolyte and dispersion were added to a beaker, and 30,000 particles were measured at a concentration that could measure the particle size of 30,000 particles in 20 seconds. determine the D _50).

[Ester group concentration]
The ester group concentration (mmol / g) is represented by the number (substance amount) of ester groups contained per 1 g of the constituent site derived from the polyester resin. For example, the ester group concentration of the constituent part derived from the polyester resin of the polyester resin A is calculated by the following formula.

[In the formula, A is the total ester bond amount (mol) produced when all of the raw material monomer (E) of the polyester resin is reacted, and B is the total mass (g of raw material monomer (E) of the constituent site derived from the polyester resin) ). In addition, the inside of () in a formula means the unit of each numerical value. ]

[Production of resin]
Production Example A1 (Production of Resin A-1)
The polyester resin raw material monomer and esterification catalyst shown in Table 1 were placed in a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser equipped with a dehydrating tube, and a nitrogen inlet tube. Then, the mixture was heated to 180 ° C. in a nitrogen atmosphere, then heated to 230 ° C. by 5 ° C. every hour, and after confirming that all the solid monomers had melted, the pressure was reduced to 60 torr and dehydration condensation was performed for 1 hour. After cooling to 160 ° C under normal pressure and adding polymer A, the reaction was further continued for 1 hour at 220 ° C, followed by a condensation reaction at 220 ° C and 60 torr, and the softening point shown in Table 1 It was made to react until it reached | attained the point and resin A-1 was obtained.

Production Examples A2 to A8, A51 to A53 (Production of Resins A-2 to A-8, A-51 to A-53)
Resins A-2 to A-8 and A-51 to A-53 were obtained in the same manner as in Production Example A1, except that the raw materials were of the types and amounts shown in Table 1.

Production Examples A9 and A54 to 55 (Production of Resins A-9 and A-54 to A-55)
10 liters equipped with raw material monomers and esterification catalyst of polyester resin other than trimellitic anhydride shown in Table 1 and cocatalyst thermometer, stainless steel stirring rod, flow-down condenser with dehydration tube and nitrogen introduction tube In a four-necked flask, heat to 180 ° C in a nitrogen atmosphere, then raise the temperature to 230 ° C by 5 ° C every hour, confirm that all the solid monomer has melted, and then reduce the pressure to 60 torr for 1 hour. It was dehydrated and condensed. After cooling to 160 ° C under normal pressure and adding polymer A and trimellitic anhydride, the reaction was further continued for 1 hour at 220 ° C, followed by a condensation reaction at 220 ° C and 60 torr, and the softening point. Were reacted until the softening point shown in Table 1 was reached, to give resins A-9 and A-54 to A-55.

[Production of toner]
Examples 1 to 8 and Comparative Examples 1 to 3 (Production of Toners 1 to 8, 51 to 53)
100 parts by weight of the binder resin shown in Table 2 in total, 1 part by weight of negatively chargeable charge control agent “Bontron E-81” (manufactured by Orient Chemical Co., Ltd.), colorant “Pigment blue 15: 3” (Daiichi Seika) 5 parts by mass of Kogyo Co., Ltd. and 2 parts by mass of release agent “HNP-9” (manufactured by Nippon Seiwa Co., Ltd., paraffin wax, melting point: 80 ° C.) are thoroughly mixed with a Henschel mixer, and then the total length of the kneaded part Using a co-rotating twin screw extruder of 1560 mm, screw diameter 42 mm, barrel inner diameter 43 mm, melt kneading was performed at a roll rotation speed of 200 r / min and a heating temperature of 100 ° C. in the roll. The feed rate of the mixture was 20 kg / h, and the average residence time was about 18 seconds. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized with a jet mill and classified to obtain toner particles having a volume-median particle size (D ₅₀ ) of 8 μm.

  To 100 parts by mass of the obtained toner particles, 2.0 parts by mass of an external additive “Aerosil R-972” (hydrophobic silica, manufactured by Nippon Aerosil Co., Ltd., number average particle size: 16 nm) is added, and 3600 r / min with a Henschel mixer. By mixing for 5 minutes, the external additive treatment was performed to obtain toners 1 to 8, 51 to 53.

[Evaluation methods]
[Fixability to PP film]
The toner is mounted on a non-magnetic one-component developing device "OKI MICROLINE 5400" (manufactured by Oki Data Corporation), by adjusting the amount of toner adhesion to 0.45 ± 0.03mg / cm ^2, non-solid image 4.1 cm × 13.0 cm It was printed on a treated biaxially stretched polypropylene film “Torphan Industrial Type 2500” (manufactured by Toray Industries, Inc., 60 μm thick) and fixed at a fixing temperature of 130 ° C.
The obtained solid image fixed on the untreated biaxially stretched polypropylene film was traced with a needle, and the toner layer peeling on the solid surface was evaluated. At this time, the mass applied to the needle was changed to 20 g, 50 g, and 100 g.
(Evaluation criteria)
A: No toner layer peeling at 100 g load B: No toner layer peeling at 50 g load, but toner layer peeling at 100 g load C: Toner layer peeling at 20 g load No, but the toner layer peels off at a load of 50 g D: The toner layer peels off at a load of 20 g

[Fixability to PET film]
Except for changing the untreated biaxially stretched polypropylene film to the untreated biaxially stretched PET film “FE2000” (Futamura Chemical Co., Ltd., thickness 70 μm) Based on the evaluation criteria, the fixability to a PET film was evaluated.

  As described above, it can be seen that the toners of the examples exhibit excellent fixability to the PP film and the PET film as compared with the toners of the comparative examples.

Claims (6)

A binder resin composition for toner containing amorphous polyester resin A,
The amorphous polyester resin A has a constituent part derived from a polyester resin and a constituent part derived from a modified polypropylene polymer A having a carboxylic acid group or a carboxylic anhydride group, and a constituent part derived from the polyester resin. And the component part derived from the modified polypropylene polymer A are linked via a covalent bond,
The polymer A is a polypropylene polymer modified with a carboxylic acid compound having an unsaturated bond or an anhydride thereof,
A binder resin composition for toner, wherein an ester group concentration of a constituent site derived from the polyester resin of the amorphous polyester resin A is 6 mmol / g or more.   The binder resin composition according to claim 1, wherein the constituent site derived from the polyester resin and the constituent site derived from the modified polypropylene polymer A are linked by an ester bond.   The binder resin composition according to claim 1 or 2, wherein the carboxylic acid compound having an unsaturated bond or an anhydride thereof is maleic anhydride.   The constituent site derived from the polyester resin is a polycondensate of an alcohol component and a carboxylic acid component, and the aliphatic alcohol having 2 to 6 carbon atoms in the alcohol component is 50% by mass or more. 4. The binder resin composition according to any one of 3 above.   The binder resin composition according to any one of claims 1 to 4, wherein the number average molecular weight of the polymer A is 500 or more and 8,000 or less.   An electrostatic charge image developing toner comprising the binder resin composition according to claim 1.