toner

Abstract

To provide a toner that satisfies low temperature fixability and heat-resistant storage properties in a high-speed machine, and is excellent in hot offset resistance and placement properties.SOLUTION: Toner has a toner particle having a binder resin, and the binder resin contains an amorphous resin A and a crystalline resin C. In viscoelasticity measurement of the toner, when a temperature at which a storage modulus G' becomes 3.0×107 Pa is defined as T1(°C), a temperature at which the storage modulus G' becomes 1.0×107 Pa as T2(°C), and a temperature at which the storage modulus G' becomes 3.0×106 Pa as T3(°C), the T1, the T2, and the T3 satisfy specific relationships. The storage modulus G'(100) at 100°C is within a specific range. When a cross section of the toner is observed, a matrix-domain structure having a matrix formed of the crystalline resin C and domains formed of the amorphous resin A is observed, and an area ratio and the number-based average area of the domains are within specific ranges.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to toner used in electrophotography and electrostatic recording. [Background technology]

[0002] Traditionally, energy conservation has been considered a major technical challenge in electrophotographic equipment, and significant reductions in the amount of heat required for the fuser have been explored. In particular, there is a growing need for so-called "low-temperature fixing" toners, which enable fixing with lower energy consumption.

[0003] As a method to enable fixing at low temperatures, for example, Patent Document 1 describes the study of toner with added plasticizers. Plasticizers have the effect of accelerating the softening rate of the binder resin while maintaining the glass transition temperature (Tg) of the toner, and can improve low-temperature fixing performance. However, since the toner softens through the step of plasticizing the binder resin after the plasticizer has melted, there is a limit to the melting rate of the toner, and further improvement in low-temperature fixing performance is desired.

[0004] Therefore, methods using crystalline resins as binders are being considered. Amorphous resins, which are commonly used as binders for toners, do not show a clear endothermic peak in differential scanning calorimeter (DSC) measurements, but when crystalline resin components are included, an endothermic peak (melting point) appears in DSC measurements.

[0005] Crystalline resins possess the property of hardly softening at temperatures below their melting point due to the regular arrangement of their molecular chains. Furthermore, above the melting point, the crystals melt rapidly, resulting in a sharp decrease in viscosity. For these reasons, they are attracting attention as materials exhibiting excellent sharp-melt properties and low-temperature fixability. In Patent Document 2, there is proposed a toner having toner particles containing a binder resin and a colorant, wherein the binder resin contains an amorphous resin A and a crystalline resin C, the melting point Tm(C) of the crystalline resin C is 50°C or higher and 110°C or lower, and in cross-sectional observation of the toner particles, a sea-island structure composed of a sea portion mainly composed of the crystalline resin C and an island portion mainly composed of the amorphous resin A is observed.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] The toner described in Patent Document 2 can be fixed with low energy and can form an image that is resistant to external forces such as rubbing and scratching. However, it has been found that it is difficult to achieve both hot offset resistance while satisfying particularly the low-temperature fixing property and heat-resistant storage property in high-speed machines. Also, problems have been found regarding the stacking property in high-speed machines (characteristics related to the adhesion between papers that occurs when printed papers are placed in a state where they overlap while having heat). The present disclosure provides a toner that satisfies low-temperature fixing property and heat-resistant storage property in high-speed machines, and further has excellent hot offset resistance and stacking property.

Means for Solving the Problems

[0008] The present disclosure is a toner having toner particles having a binder resin, the binder resin contains an amorphous resin A and a crystalline resin C, The amorphous resin A has a monomer unit (c) represented by the following formula (7), in viscoelastic measurement of the toner, the storage elastic modulus G' is [3.0×10] 7Let T1 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 1.0 × 10⁻⁶. 7 Let T2 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 3.0 × 10⁻⁶. 6 When the temperature at which Pa is obtained is T3 [°C], T1, T2, and T3 are given by the following formulas (1) and (2): T3 - T1 ≤ 10.0 (1) 50.0 ≤ T2 ≤ 70.0 (2) Satisfied, In the viscoelasticity measurement of the toner, the storage modulus G'(100) at 100°C was 1.0 × 10⁻⁶. 4 ~1.0×10 6 Pa, When the cross-section of the toner was observed using a scanning transmission electron microscope, In the cross-section, a matrix-domain structure having a matrix of crystalline resin C and domains of amorphous resin A was observed. The area ratio of the domain in the cross-section of the toner is 60~90 This is an area percentage. The average area of ​​the domains in the cross-section of the toner, based on the number of domains, is 200 to 3,000 nm. 2 This concerns toner. TIFF0007911892000001.tif56153 (In formula (7), R 2 (where m represents a hydrogen atom or methyl group, and m represents an integer between 7 and 35.) [Effects of the Invention]

[0009] This disclosure makes it possible to provide a toner that satisfies low-temperature fixing performance and heat-resistant storage requirements in high-speed machines, and further exhibits excellent resistance to hot offsetting and load capacity. [Brief explanation of the drawing]

[0010] [Figure 1] Example of sample mounting during viscoelasticity measurement [Modes for carrying out the invention]

[0011] In the present disclosure, descriptions such as "XX or more and YY or less" and "XX to YY" representing numerical ranges mean numerical ranges including the lower limit and the upper limit, which are the endpoints, unless otherwise specified. When numerical ranges are described stepwise, the upper and lower limits of each numerical range can be arbitrarily combined. (Meta)acrylic ester means acrylic ester and / or methacrylic ester.

[0012] "Monomer unit" refers to the reacted form of the monomer substance in the polymer. For example, in the main chain of the polymerized vinyl monomer in the polymer, one section of the carbon-carbon bond is regarded as one unit. The vinyl monomer can be represented by the following formula (C). [Chemical formula]

[0013] [In formula (C), R A represents a hydrogen atom or an alkyl group (preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group), and R B represents an arbitrary substituent.] Crystalline resin refers to a resin that shows a distinct endothermic peak in differential scanning calorimetry (DSC) measurement.

[0014] The inventors of the present invention have found that the above problems can be solved by appropriately controlling the matrix domain structure having a matrix by the crystalline resin C and a domain by the amorphous resin A when observing the cross-section of the toner in the viscoelastic measurement of the toner. The present disclosure is a toner having toner particles having a binder resin, where the binder resin contains an amorphous resin A and a crystalline resin C, in the viscoelastic measurement of the toner, let the temperature at which the storage modulus G' becomes 3.0×10 7 Pa be T1 [°C], the temperature at which the storage modulus G' becomes 1.0×10 7 Pa be T2 [°C], and the storage modulus G' be 3.0×10 6 ​When the temperature at which Pa is obtained is T3 [°C], The values ​​of T1, T2, and T3 are given by the following equations (1) and (2) T3 - T1 ≤ 10.0 (1) 50.0 ≤ T2 ≤ 70.0 (2) Satisfied, In the viscoelasticity measurement of the toner, the storage modulus G'(100) at 100°C was 1.0 × 10⁻⁶. 4 ~1.0×10 6 Pa, When the cross-section of the toner was observed using a scanning transmission electron microscope, In the cross-section, a matrix-domain structure having a matrix of crystalline resin C and domains of amorphous resin A was observed. The area ratio of the domain in the cross-section of the toner is 45-95 area%, The average area of ​​the domains in the cross-section of the toner, based on the number of domains, is 100 to 100,000 nm. 2 This concerns toner.

[0015] To achieve both low-temperature fixability and heat-resistant storage, the storage modulus must be high up to the temperature required for heat-resistant storage, and then rapidly decrease at temperatures higher than that, i.e., exhibit sharp melt properties (Equations (1) and (2)). Furthermore, controlling the storage modulus at high temperatures provides resistance to hot offsetting. To control these properties, it is important to appropriately control the matrix-domain structure (sea-island structure) which consists of a matrix (sea area) made of crystalline resin C and domains (island areas) made of amorphous resin A when observing the cross-section of the toner. This also makes it possible to improve the load-bearing capacity.

[0016] The following provides a detailed explanation of toner. In the viscoelasticity measurement of toner, the storage modulus G' is 3.0 × 10⁻⁶. 7 Let T1 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 1.0 × 10⁻⁶. 7 Let T2 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 3.0 × 10⁻⁶. 6Let T3 [°C] be the temperature at which Pa is obtained. In this case, T1, T2, and T3 satisfy the following equations (1) and (2). T3 - T1 ≤ 10.0 (1) 50.0 ≤ T2 ≤ 70.0 (2)

[0017] By satisfying equations (1) and (2), it is possible to achieve both low-temperature fixing, stacking, and heat-resistant storage of toner in high-speed machines. If T3-T1 is greater than 10.0°C, low-temperature fixing and stacking performance in high-speed machines will decrease. Preferably, the temperature is 8.0°C or lower, and more preferably 7.0°C or lower. The lower limit is not particularly limited, but preferably 1.0°C or higher, 3.0°C or higher, and 5.0°C or higher. For example, preferred ranges include 1.0-8.0°C, 3.0-8.0°C, 5.0-8.0°C, 3.0-7.0°C, and 5.0-7.0°C.

[0018] T3-T1 can be controlled by factors such as the proportion of crystalline resin C in the toner, the proportion of crystalline regions in crystalline resin C, the shape of the domains in the matrix domain structure, the ratio of matrix to domains, and the composition of the matrix domains. T1 is preferably 46.0 to 65.0°C, and more preferably 52.0 to 56.0°C. T3 is preferably 54.0 to 71.0°C, and more preferably 58.0 to 62.0°C.

[0019] Furthermore, if T2 is less than 50.0°C, it is advantageous for low-temperature fixing performance, but the stackability and heat resistance of the toner decrease. On the other hand, if T2 is greater than 70.0°C, it exhibits excellent heat resistance, but the low-temperature fixing performance decreases. T2 is preferably 55.0 to 65.0°C, more preferably 56.0 to 60.0°C, and even more preferably 57.0 to 59.0°C.

[0020] T2 can be controlled by the length of the long-chain alkyl group and the proportion of the long-chain alkyl group in the crystalline resin when the crystalline resin C is a vinyl resin having a long-chain alkyl group. Furthermore, when the crystalline resin C is a polyester resin, T2 can be controlled by the number of carbon atoms in the diol and dicarboxylic acid components used.

[0021] Next, in the viscoelasticity measurement of the toner, the storage modulus G'(100) at 100°C was 1.0 × 10⁻⁶. 4 ~1.0×10 6 The storage modulus G'(100) is 1.0 × 10⁻⁶. 4 When the value is less than Pa, the resistance to hot offset decreases. Also, the storage modulus G'(100) at 100°C is 1.0 × 10⁻⁶. 6 When the value exceeds Pa, the ability to fixate at low temperatures decreases. The storage modulus G'(100) at 100°C can be controlled by the shape of the domains in the matrix-domain structure, the ratio of matrix to domains, the composition of matrix and domains, crosslinking, etc. The storage modulus G'(100) is preferably 4.0 × 10⁻⁶ 4 ~6.0×10 5 Pa is more preferably 8.0 × 10 4 ~3.0×10 5 It is Pa.

[0022] Next, when the cross-section of the toner is observed using a scanning transmission electron microscope, a matrix-domain structure (sea-island structure) is observed in the cross-section, which has a matrix (sea region) made of crystalline resin C and domains (island regions) made of amorphous resin A. Materials added as needed, such as colorants, may be dispersed in the domains and matrix. Furthermore, the domain area ratio in the toner cross-section is 45-95% area, and the average area based on the number of domains is 100-100,000 nm. 2 That is the case.

[0023] When crystalline resin C is present as the matrix and amorphous resin A as the domains, it becomes easier to maintain sharp melt properties and shape after fixing, thus satisfying low-temperature fixing and loadability requirements for high-speed machines. The reason is that if the matrix is ​​crystalline resin C, the influence of the matrix during fixing can be greatly increased, allowing for the development of sharp melt properties. Furthermore, the presence of amorphous resin A in domains makes it easier to maintain the shape after fixing, thus satisfying the load-bearing requirements.

[0024] If the matrix is ​​an amorphous resin and the domains are crystalline resin C, the sharp melt properties decrease, and it becomes difficult to maintain the shape after fixing, making it impossible to satisfy the low-temperature fixing and loading requirements for high-speed machines. The matrix domain structure can be controlled by factors such as the compatibility of crystalline resin C and amorphous resin A, the ratio of crystalline resin C to amorphous resin A, and the conditions for the formation of amorphous resin A (polymerization rate and temperature). For example, even when the amount of crystalline resin C is less than the amount of amorphous resin A, the polymerization rate can be improved and the average area of ​​the islands can be controlled to be smaller by controlling the compatibility of crystalline resin C and amorphous resin A, as well as the monomer units and formation conditions (polymerization rate and temperature) of amorphous resin A, thereby enabling the formation of a matrix by crystalline resin C.

[0025] If the domain area ratio in the cross-section is less than 45%, the domains will not be able to contact each other during fixing, which will reduce elasticity and decrease hot offset resistance and load capacity. If the domain area ratio in the cross-section is greater than 95%, the relative ratio of the matrix will decrease, which will reduce sharp melt properties during fixing and decrease low-temperature fixing properties.

[0026] The area ratio of domains in the cross-section of the toner can be controlled by factors such as the compatibility of crystalline resin C and amorphous resin A, the ratio of crystalline resin C to amorphous resin A, and the conditions for the formation of amorphous resin A (polymerization rate and temperature conditions). Furthermore, the area ratio of domains in the cross-section is preferably 60-90 area%, more preferably 70-90 area%, and even more preferably 70-80 area%.

[0027] Next, the average area based on the number of domains is 100 nm. 2As the size decreases, the elasticity tends to decrease during fixing, resulting in reduced load capacity. Furthermore, the average area based on the number of domains is 100,000 nm. 2 As the size increases, the domains can no longer make contact with each other, leading to a decrease in elasticity during anchoring. This, in turn, reduces resistance to hot offset and load capacity.

[0028] The average area based on the number of domains can be controlled by factors such as the compatibility of crystalline resin C and amorphous resin A, the ratio of crystalline resin C to amorphous resin A, and the conditions for the formation of amorphous resin A (polymerization rate and temperature conditions). The average domain area is 100-10,000 nm. 2 Preferably, the wavelength is 200-3,000 nm. 2 It is more preferable that the wavelength be 250-500nm. 2 It is even more preferable that this be the case.

[0029] The toner contains toner particles that include a binder resin. The binder resin contains crystalline resin C. Examples of crystalline resin C include crystalline vinyl resins, polyester resins, polyurethane resins, epoxy resins, etc., but crystalline vinyl resin is preferred. When the crystalline resin C is a vinyl resin having crystalline properties, it is preferable that it has monomer units (a) represented by the following formula (3).

[0030] In formula (3), R 4 represents a hydrogen atom or a methyl group, and n represents an integer between 15 and 35. [ka]

[0031] Having monomer unit (a) represented by formula (3) makes it easier for the crystalline resin C to form a side-chain crystalline structure, thus enabling both sharp melting and rapid crystallization. This makes it easier to improve low-temperature fixing performance and load capacity during high-speed fixing. When n in equation (3) is 15 or greater, the melting point tends to be higher, which improves heat resistance for storage and load capacity. When n in formula (3) is 35 or less, crystallinity is improved, and sharp melt properties and stackability tend to improve. The value of n in formula (3) is preferably 17 to 29, and more preferably 19 to 23.

[0032] One method for introducing monomer unit (a) is to polymerize (meth)acrylic acid esters as follows: For example, (meth)acrylic acid esters having a linear alkyl group with 16 to 36 carbon atoms [stearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, octacosyl (meth)acrylate, myricyl (meth)acrylate, dotriacontyl (meth)acrylate, etc.] and (meth)acrylic acid esters having a branched alkyl group with 18 to 36 carbon atoms [2-decyltetradecyl (meth)acrylate, etc.]. The monomers forming the monomer unit (a) may be one type alone or two or more types in combination.

[0033] If the crystalline resin C is a vinyl resin having crystalline properties, it is possible to have other monomer units in addition to monomer unit (a). One method for introducing other monomer units is to polymerize the (meth)acrylic acid ester with other vinyl monomers.

[0034] Other vinyl monomers include the following: (Meth)acrylic acid esters such as styrene, α-methylstyrene, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Monomers having a urea group: For example, monomers obtained by reacting a carbon 3-22 amine [primary amines (n-butylamine, t-butylamine, propylamine, and isopropylamine, etc.), secondary amines (di-normal ethylamine, di-normal propylamine, di-normal butylamine, etc.), aniline, and cycloxylamine, etc.)] with a carbon 2-30 isocyanate having an ethylenically unsaturated bond by known methods. Monomers having a carboxyl group; for example, methacrylic acid, acrylic acid, and 2-carboxyethyl (meth)acrylate. Monomers having a hydroxyl group; for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc. Monomers having an amide group; for example, acrylamide, monomers obtained by reacting an amine having 1 to 30 carbon atoms with a carboxylic acid having 2 to 30 carbon atoms having an ethylenically unsaturated bond (such as acrylic acid and methacrylic acid) by known methods. In particular, styrene, methacrylic acid, acrylic acid, methyl (meth)acrylate, and t-butyl (meth)acrylate are preferred.

[0035] In crystalline resin C, the content of monomer unit (a) represented by formula (3) is preferably 50.0 to 100.0% by mass. When the content is 50.0% by mass or more, the melting point tends to be higher, and heat resistance, low-temperature fixation, and stackability tend to be improved. The lower limit is more preferably 60.0% by mass or more, even more preferably 65.0% by mass or more, and even more preferably 70.0% by mass or more. The upper limit is more preferably 95.0% by mass or less, even more preferably 90.0% by mass or less, and even more preferably 85.0% by mass or less. For example, preferably 60.0 to 95.0% by mass, and 65.0 to 90.0% by mass. 70.0 to 85.0% by mass is a possible range. Furthermore, if crystalline resin C contains two or more monomer units (a), the content ratio of monomer unit (a) is the sum of those units.

[0036] The crystalline resin C preferably has monomer units made of styrene represented by the following formula (A). Furthermore, the crystalline resin C preferably has monomer units made of (meth)acrylic acid represented by the following formula (B). [ka] In formula (B), R 3 R represents a hydrogen atom or a methyl group. 3 Preferably, it is a methyl group.

[0037] In crystalline resin C, the content of monomer units made of styrene is preferably 1.0 to 50.0% by mass, more preferably 10.0 to 30.0% by mass, and even more preferably 15.0 to 25.0% by mass. In crystalline resin C, the content of monomer units by (meth)acrylic acid (preferably methacrylic acid) is preferably 0.5 to 5.0% by mass, more preferably 1.0 to 3.0% by mass, and even more preferably 1.5 to 2.5% by mass.

[0038] When crystalline resin C is a polyester resin, any polyester resin that exhibits crystalline properties can be used, which can be obtained by the reaction of a divalent or higher polycarboxylic acid with a polyhydric alcohol.

[0039] Examples of polycarboxylic acids include the following compounds: dibasic acids such as succinic acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, malonic acid, and dodecenylsuccinic acid, and their anhydrides or lower alkyl esters, as well as aliphatic unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, and citraconic acid. Other examples include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and their anhydrides or lower alkyl esters. These may be used individually or in combination of two or more.

[0040] Examples of polyhydric alcohols include the following compounds: alkylene glycols (ethylene glycol, 1,2-propylene glycol, and 1,3-propylene glycol); alkylene ether glycols (polyethylene glycol and polypropylene glycol); alicyclic diols (1,4-cyclohexanedimethanol); bisphenols (bisphenol A); and alkylene oxide (ethylene oxide and propylene oxide) adducts of alicyclic diols. The alkyl portions of alkylene glycols and alkylene ether glycols may be linear or branched. Furthermore, examples include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These may be used individually or in combination of two or more.

[0041] Furthermore, monohydric acids such as acetic acid and benzoic acid, and monohydric alcohols such as cyclohexanol and benzyl alcohol may be used as needed to adjust the acid value and hydroxyl value. The method for producing the polyester resin is not particularly limited, but for example, the transesterification method or the direct polycondensation method can be used alone or in combination.

[0042] The content of crystalline resin C in the toner is preferably 10.0 to 60.0% by mass. Being within this range further promotes the crystallization of the toner, allowing for a better balance between sharp meltability and high-speed crystallization, and further improving low-temperature fixing and stackability during high-speed fixing.

[0043] The lower limit of the content of crystalline resin C is more preferably 15.0% by mass or more, even more preferably 20.0% by mass or more, even more preferably 25.0% by mass or more, and particularly preferably 30.0% by mass or more. The upper limit is more preferably 55.0% by mass or less, even more preferably 50.0% by mass or less, even more preferably 40.0% by mass or less, and particularly preferably 35.0% by mass or less. The content of crystalline resin C is preferably, for example, 15.0 to 55.0% by mass, 20.0 to 50.0% by mass, 25.0 to 40.0% by mass, or 30.0 to 35.0% by mass.

[0044] The binder resin contains amorphous resin A in addition to crystalline resin C. Examples of amorphous resin A include vinyl resin, polyester resin, polyurethane resin, epoxy resin, etc., but vinyl resin and polyester resin are preferred. Amorphous resin A is more preferably vinyl resin. Amorphous resin A preferably has monomer units (b) represented by the following formula (4).

[0045] In formula (4), R 1 R represents a hydrogen atom or a methyl group. 5 represents an alkyl group having 1 to 4 carbon atoms (preferably either a methyl group or a t-butyl group). [ka]

[0046] Having monomer units (b) shown in formula (4) below makes it easier to reduce the domain area. Therefore, the contact area between domains can be improved during fixation, making it easier to improve load capacity. The monomers forming the monomer unit (b) may be one type alone or two or more types in combination.

[0047] If amorphous resin A is a vinyl resin, one method for introducing monomer unit (b) is to polymerize a vinyl monomer capable of adopting the monomer unit (b) structure. Furthermore, if amorphous resin A is a vinyl resin, it is possible to have other monomer units in addition to the monomer unit (b) mentioned above. One method for introducing other monomer units is to polymerize vinyl monomers that can take on other monomer unit structures.

[0048] Preferred vinyl monomers that can take the monomer unit (b) structure include methyl acrylate, methyl methacrylate, t-butyl acrylate, and t-butyl methacrylate. By selecting these vinyl monomers, the reactivity between vinyl monomers tends to increase, allowing for the control of a smaller domain area.

[0049] In amorphous resin A, the content of monomer unit (b) is preferably 5.0 to 60.0% by mass. The lower limit is more preferably 10.0% by mass or more, even more preferably 20.0% by mass or more, even more preferably 30.0% by mass or more, and particularly preferably 35.0% by mass or more. The upper limit is more preferably 55.0% by mass or less, even more preferably 50.0% by mass or less, even more preferably 45.0% by mass or less, and particularly preferably 40.0% by mass or less. For example, preferred values ​​are 10.0 to 55.0% by mass, 20.0 to 50.0% by mass, 30.0 to 45.0% by mass, and 35.0 to 40.0% by mass. Furthermore, if amorphous resin A contains two or more monomer units (b), the content ratio of monomer units (b) will be the sum of those units.

[0050] For example, amorphous resin A is R in formula (4). 5 It is preferable to have at least one monomer unit b1 selected from the group consisting of monomer units in which is a methyl group or a t-butyl group. In amorphous resin A, the content of monomer unit b1 is preferably 25.0 to 50.0% by mass, more preferably 30.0 to 45.0% by mass, and even more preferably 35.0 to 40.0% by mass. Furthermore, amorphous resin A also contains R in formula (4). 5 The monomer unit b2 may be an n-butyl group. The content of monomer unit b2 in amorphous resin A is preferably 3.0 to 20.0% by mass, and more preferably 7.0 to 11.0% by mass.

[0051] The amorphous resin A preferably has monomer units (c) represented by the following formula (7). In formula (7), R 2 represents a hydrogen atom or a methyl group, and m represents an integer between 7 and 35. [ka]

[0052] The presence of monomer units (c) allows for control over compatibility with crystalline resin C, making it easier to improve adhesion at the interface between crystalline resin C and amorphous resin A in the toner, and thus improving the durability of the toner. Furthermore, the presence of monomer units (c) makes it easier to control the entanglement of resins in the matrix, thus making it easier to increase the storage modulus G'(100). A preferred range for m is 7 to 29, more preferably 7 to 19, even more preferably 7 to 15, even more preferably 7 to 14, especially preferably 9 to 14, and particularly preferably 9 to 13.

[0053] In addition to the (meth)acrylic acid esters usable for monomer unit (a), methods for introducing monomer unit (c) include polymerizing the following (meth)acrylic acid esters: for example, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, and palmityl (meth)acrylate. The monomers forming the monomer unit (c) may be one type alone or two or more types in combination.

[0054] Amorphous resin A may also contain other monomer units in addition to monomer unit (c). Methods for introducing other monomer units include polymerizing the (meth)acrylic acid ester mentioned above and vinyl monomers that can be used in crystalline resin C. For example, amorphous resin A may contain 25.0 to 50.0% by mass of monomer units made of styrene. Furthermore, amorphous resin A may have monomer units formed by known crosslinking agents such as hexanediol diacrylate, which have multiple vinyl groups, acryloyl groups, methacryloyl groups, etc.

[0055] The monomer unit (c) content in amorphous resin A is preferably 5.0 to 40.0% by mass. The lower limit is more preferably 10.0% by mass or more, and even more preferably 15.0% by mass or more. The upper limit is more preferably 35.0% by mass or less, even more preferably 30.0% by mass or less, and even more preferably 25.0% by mass or less. For example, preferred amounts include 10.0 to 35.0 mass%, 15.0 to 30.0 mass%, and 15.0 to 25.0 mass%.

[0056] When amorphous resin A is a polyester resin, any polyester resin that does not exhibit crystallinity can be used, which can be obtained by the reaction of a divalent or higher polycarboxylic acid with a polyhydric alcohol as described above.

[0057] The content of amorphous resin A in the binder resin is preferably 20.0 to 90.0% by mass, more preferably 50.0 to 80.0% by mass, and even more preferably 60.0 to 75.0% by mass.

[0058] The weight-average molecular weight (Mw) of the tetrahydrofuran (THF) soluble portion of the toner, as measured by gel permeation chromatography (GPC), is preferably between 10,000 and 200,000. The lower limit is more preferably 30,000 or higher, and even more preferably 50,000 or higher. The upper limit is more preferably 180,000 or lower. Having Mw within the above range makes it easier to improve the low-temperature fixability and durability of the toner.

[0059] The toner may contain a release agent. The release agent may be a hydrocarbon wax or an ester wax. It is preferable that the wax be at least one selected from the group consisting of waxes. Using hydrocarbon waxes and / or ester waxes makes it easier to ensure effective release properties.

[0060] There are no particular limitations on hydrocarbon waxes, but examples include the following: Aliphatic hydrocarbon waxes: low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymers, Fischer-Tropsch waxes, or waxes obtained by oxidation or acid addition of these materials.

[0061] Ester waxes only need to have at least one ester bond in each molecule, and either natural or synthetic ester waxes may be used. There are no particular limitations on ester waxes, but examples include the following: Esters of monohydric alcohols and monocarboxylic acids, such as behenyl behenate, stearyl stearate, and palmityl palmitate; Esters of divalent carboxylic acids and monoalcohols, such as dibehenyl sebacate; Esters of dihydric alcohols such as ethylene glycol distearate and hexanediol dibehenate with monocarboxylic acids; Esters of trihydric alcohols such as glycerol tribehenate and monocarboxylic acids; Esters of tetrahydric alcohols such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate with monocarboxylic acids; Esters of hexahydritol alcohols such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabéhenate with monocarboxylic acids; Esters of polyfunctional alcohols such as polyglycerin behenates and monocarboxylic acids; natural ester waxes such as carnauba wax and rice wax;

[0062] Among these, esters of hexavalent alcohols and monocarboxylic acids, such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabéhenate, are preferred.

[0063] The release agent may be a hydrocarbon wax or an ester wax alone, or a combination of hydrocarbon wax and an ester wax, or a mixture of two or more types. However, it is preferable to use a hydrocarbon wax alone or two or more types. It is more preferable that the release agent is a hydrocarbon wax.

[0064] In toner, the content of the release agent in the toner particles is preferably 1.0% by mass or more and 30.0% by mass or less, and more preferably 2.0% by mass or more and 25.0% by mass or less. Having the release agent content in the toner particles within this range makes it easier to ensure release properties during fixing. The melting point of the release agent is preferably between 60°C and 120°C. A melting point within this range allows the release agent to melt during fixing and easily seep onto the toner particle surface, thus facilitating release properties. More preferably, the melting point is between 70°C and 100°C.

[0065] The toner may contain a colorant. Examples of colorants include known organic pigments, organic dyes, inorganic pigments, carbon black as a black colorant, and magnetic particles. Other colorants conventionally used in toners may also be used. Examples of yellow colorants include: condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, CI Pigment Yellows 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, and 180 are preferably used.

[0066] Examples of magenta colorants include: condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolon compounds, thioindigo compounds, and perylene compounds. Specifically, CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254 are preferably used. Examples of cyanide colorants include: copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specifically, CI pigment blues 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66 are preferably used.

[0067] The colorants are selected based on their hue angle, saturation, brightness, lightfastness, OHP transparency, and dispersibility in toner. The coloring agent content is preferably 1.0 part by mass or more and 20.0 parts by mass or less per 100.0 parts by mass of the binder resin. When magnetic particles are used as the coloring agent, their content is preferably 40.0 parts by mass or more and 150.0 parts by mass or less per 100.0 parts by mass of the binder resin.

[0068] A charge control agent may be incorporated into the toner particles as needed. Alternatively, the charge control agent may be added externally to the toner particles. By incorporating a charge control agent, the charge characteristics can be stabilized, and the optimal amount of triboelectric charge can be controlled according to the developing system. Known charge control agents can be used, and charge control agents that have a fast charging speed and can stably maintain a constant amount of charge are particularly preferred.

[0069] Examples of charge control agents that control the toner's charge to match the load charge include the following: Organometallic compounds and chelate compounds are effective, and examples include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, and oxycarboxylic acid and dicarboxylic acid-based metal compounds. Examples of substances that control the toner's positive charge include: nigrosine, quaternary ammonium salts, metal salts of higher fatty acids, diorganosucroses, guanidine compounds, and imidazole compounds. The charge control agent content is preferably 0.01 parts by mass to 20.0 parts by mass, and more preferably 0.5 parts by mass to 10.0 parts by mass, per 100.0 parts by mass of toner particles.

[0070] The toner particles can be used as is as toner, or, if necessary, external additives can be mixed in and attached to the surface of the toner particles to create toner. Examples of external additives include inorganic fine particles selected from the group consisting of silica fine particles, alumina fine particles, and titania fine particles, or composite oxides thereof. Examples of composite oxides include silica-aluminum fine particles and strontium titanate fine particles. The content of the external additive is preferably 0.01 parts by mass or more and 8.0 parts by mass or less per 100 parts by mass of toner particles, and more preferably 0.1 parts by mass or more and 4.0 parts by mass or less.

[0071] The weight-average particle size (D4) of the toner is not particularly limited, but is preferably 4.0 to 12.0 μm, and more preferably 6.0 to 8.0 μm.

[0072] Toner particles may be manufactured by any known method, such as suspension polymerization, emulsification and agglutination, dissolution and suspension, or pulverization, as long as they are within the scope of the present configuration, but are preferably manufactured by suspension polymerization.

[0073] I will now describe the suspension polymerization method in detail. For example, polymerizable monomers that produce a pre-synthesized crystalline resin C and amorphous resin A, along with other materials such as colorants, release agents, and charge control agents as needed, are mixed and uniformly dissolved or dispersed to prepare a polymerizable monomer composition. Subsequently, the polymerizable monomer composition is dispersed in an aqueous medium using a stirrer or the like to prepare suspended particles of the polymerizable monomer composition. Then, toner particles are obtained by polymerizing the polymerizable monomers contained in the particles with an initiator or the like. After polymerization is complete, the toner particles may be filtered, washed, and dried by known methods, and external additives may be added as needed to obtain toner.

[0074] As a polymerization initiator, known polymerization initiators can be used. Examples of azo or diazo polymerization initiators include 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonnitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobisisobutyronitrile; and peroxide polymerization initiators such as benzoyl peroxide, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutylate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumenehydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide. In addition, known chain transfer agents and polymerization inhibitors may be used.

[0075] The aqueous medium may contain an inorganic or organic dispersion stabilizer. As a dispersion stabilizer, known dispersion stabilizers can be used. Examples of inorganic dispersion stabilizers include phosphates such as hydroxyapatite, tricalcium phosphate, dicalcium phosphate, magnesium phosphate, aluminum phosphate, and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; metal hydroxides such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide; sulfates such as calcium sulfate and barium sulfate; calcium metasilicate; bentonite; silica; and alumina.

[0076] On the other hand, examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salts of carboxymethylcellulose, polyacrylic acid and its salts, and starch.

[0077] When using inorganic compounds as dispersion stabilizers, commercially available compounds may be used as is, but in order to obtain finer particles, the inorganic compounds may be generated in an aqueous medium before use. For example, in the case of calcium phosphate such as hydroxyapatite or tricalcium phosphate, it is best to mix the phosphate aqueous solution with the calcium salt aqueous solution under high stirring.

[0078] The aqueous medium may contain a surfactant. Known surfactants can be used as the surfactant. Examples include anionic surfactants such as sodium dodecylbenzene sulfate and sodium oleate; cationic surfactants; amphoteric surfactants; and nonionic surfactants.

[0079] The calculation and measurement methods for various physical properties are described below. <Method for measuring the storage modulus G'> The storage modulus G' is measured using a viscoelasticity measuring device (rheometer) called ARES (Rheometric). Measurements will be performed using a Rheometrics Scientific instrument. The general procedure for the measurement is described in the ARES operating manuals 902-30004 (August 1997 edition) and 902-00153 (July 1993 edition) published by Rheometrics Scientific, and is as follows: • Measuring jig: Torsion rectangular • Measurement sample: For the toner, a rectangular parallelepiped sample with a width of 12 mm, a height of 20 mm, and a thickness of 2.5 mm is prepared using a pressure molding machine (maintaining 25 kN for 30 minutes at room temperature). The pressure molding machine used is the NPa Systems 100kN press NT-100H.

[0080] After leaving the jig and sample at room temperature (23°C) for 1 hour, attach the sample to the jig. See Figure 1. Fix the jig so that the measuring section is 12 mm wide, 2.5 mm thick, and 10 mm high, as shown in the figure. After adjusting the temperature to 30°C over 10 minutes, perform the measurement with the settings below. ·Measurement frequency: 6.28rad / s • Setting the measurement distortion: Set the initial value to 0.1% and perform the measurement in automatic measurement mode. • Sample elongation correction: Adjusted in automatic measurement mode • Measurement temperature: The temperature is raised from 30°C to 150°C at a rate of 2°C per minute. • Measurement interval: Viscoelastic data is measured every 30 seconds, i.e., every 1°C. Data is transferred via an interface to RSI Orchestrator (control, data acquisition, and analysis software) (manufactured by Rheometrics Scientific), which runs on Microsoft Windows 2000. Of the measurement data, the storage modulus G' is 3.0 × 10⁻⁶. 7 Let T1 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 1.0 × 10⁻⁶. 7 Let T2 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 3.0 × 10⁻⁶. 6 Let T3 [°C] be the temperature at which Pa is obtained. Furthermore, the storage modulus G' at 100°C is defined as G'(100).

[0081] <Method for measuring the molecular weight of toner> The molecular weight (weight-average molecular weight Mw) of the THF-soluble component of toner is measured by gel permeation chromatography (GPC) as follows. First, the toner is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. The resulting solution is then filtered through a solvent-resistant membrane filter, "Myshoridisk" (manufactured by Tosoh Corporation), with a pore diameter of 0.2 μm, to obtain the sample solution. The sample solution is adjusted so that the concentration of THF-soluble components is 0.8% by mass. This sample solution is then used for measurement under the following conditions. • Equipment: HLC8120 GPC (Detector: RI) (Manufactured by Tosoh Corporation) • Columns: Shodex KF-801, 802, 803, 804, 805, 806, 807 (7 columns, manufactured by Showa Denko) • Eluent: Tetrahydrofuran (THF) ·Flow rate: 1.0ml / min Oven temperature: 40.0℃ • Sample injection volume: 0.10 ml To calculate the molecular weight of the sample, a molecular weight calibration curve created using standard polystyrene resin (for example, "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used.

[0082] <Method for separating crystalline resin C and amorphous resin A from toner> The separation of crystalline resin C and amorphous resin A from toner can be done by known methods, one example of which is shown below. Gradient LC is used as a method for separating resin components from toner. This analysis allows for separation based on the polarity of the resin in the binder resin, regardless of molecular weight.

[0083] First, the toner was dissolved in chloroform. The sample was adjusted to a sample concentration of 0.1% by mass using chloroform, and the solution was filtered through a 0.45 μm PTFE filter before being used for measurement. The measurement conditions for gradient polymer LC are shown below. Equipment: UlTIMATE3000 (manufactured by Thermo Fisher Scientific) Mobile phase: A. Chloroform (HPLC), B. Acetonitrile (HPLC) Gradient: 2 min (A / B = 0 / 100) → 25 min (A / B = 100 / 0) (Note: The gradient of the mobile phase change was made to be a straight line.) Flow rate: 1.0mL / min Injection: 0.1% by mass x 20μL Column: Tosoh TSKgel ODS (4.6mmφ x 150mm x 5μm) Column temperature: 40℃ Detector: Corona Charged Particle Detector (Corona-CAD) (manufactured by Thermo Fisher Scientific)

[0084] The time-intensity graph obtained from the measurement shows that the resin component can be separated into two peaks depending on its polarity. Subsequently, by repeating the above measurement and sampling at the time of the trough of each peak, it is possible to separate the resin into two types. DSC measurement is performed on the separated resins, and the resin with a melting point peak is designated as crystalline resin C, and the resin without a melting point peak is designated as amorphous resin A.

[0085] Furthermore, if the toner contains a release agent, it is necessary to separate the release agent from the toner. The release agent is separated by recycled HPLC, which separates components with a molecular weight of 2000 or less as the release agent. The measurement method is as follows. First, a chloroform solution of the toner is prepared using the method described above. Then, the obtained solution is filtered through a solvent-resistant membrane filter "Myshoridisk" (manufactured by Tosoh Corporation) with a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of components soluble in chloroform is 1.0 mass%. This sample solution is used for measurement under the following conditions. ·Equipment: LC-Sakura NEXT (manufactured by Nippon Analytical Industry Co., Ltd.) • Columns: JAIGEL2H, 4H (manufactured by Nippon Analytical Engineering Co., Ltd.) • Eluent: Chloroform ·Flow rate: 10.0ml / min Oven temperature: 40.0℃ • Sample injection volume: 1.0 ml To calculate the molecular weight of the sample, a molecular weight calibration curve created using standard polystyrene resin (for example, "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used. From the molecular weight curve obtained in this way, components with a molecular weight of 2000 or less are repeatedly separated, and the release agent is removed from the toner.

[0086] <Method for measuring the content ratio of various monomer units in resin> The measurement of the content ratio of various monomer units in the resin is performed by 1 The procedure is performed by 1H-NMR under the following conditions. Crystalline resin C and amorphous resin A, separated by the method described above, can be used as the measurement samples. Measuring device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.) Measurement frequency: 400MHz Pulse condition: 5.0 μs Frequency range: 10500Hz Total number of times: 64 Measurement temperature: 30℃ Sample: Place 50 mg of the sample to be measured into a sample tube with an inner diameter of 5 mm, add deuterated chloroform (CDCl3) as a solvent, and dissolve in a constant temperature bath at 40°C to prepare the sample. 1 The H-NMR chart is analyzed to identify the structure of each monomer unit. Here, as an example, the measurement of the content of monomer unit (a) in crystalline resin C is described. 1 In the H-NMR chart, a peak independent of the peaks attributed to the components of monomer unit (a) is selected from among the peaks attributed to the components of the other monomer units, and the integral value S1 of this peak is calculated. The integral values ​​are similarly calculated for the other monomer units contained in the crystalline resin C.

[0087] When the monomer units constituting the crystalline resin C consist of monomer unit (a) and one other monomer unit, the content ratio of monomer unit (a) is determined as follows using the integral value S1 and the integral value S2 of the peak of the other monomer unit. Note that n1 and n2 are the number of hydrogen atoms in the constituent element to which the peak of interest belongs for each part. Percentage of monomer unit (a) (mol %) = {(S1 / n1) / ((S1 / n1)+(S2 / n2))}×100 Similarly, even if there are two or more other monomer units, the content ratio of monomer unit (a) can be calculated (using S3···Sx and n3···nx).

[0088] Furthermore, if a polymerizable monomer is used in which no hydrogen atoms are present in any component other than the vinyl group, 13 The atomic nuclei to be measured using C-NMR 13 Let C be used, and the measurement will be performed in single-pulse mode. 1 The same calculation is performed using 1H-NMR. The percentage (mol%) of each monomer unit calculated by the above method is multiplied by the molecular weight of each monomer unit to convert the content of each monomer unit into mass%. The same method is used for measurements of amorphous resin A.

[0089] <Observation of matrix domain structure in toner cross-section, domain area ratio, and average area based on domain number> The presence of matrix domain structures (sea-island structures) in the cross-section of toner is confirmed by observing the cross-section of the toner using a scanning transmission electron microscope. The cross-sectional observation of the toner is performed after ruthenium staining. That is, the cross-sectional image of the toner is a cross-sectional image of ruthenium-stained toner. The procedure for observing the cross-section of the toner is as follows:

[0090] The toner is dispersed as much as possible, embedded in a visible light-curable resin (D-800, manufactured by Nisshin EM Co., Ltd.), and then cut to a thickness of 100 nm using an ultrasonic ultramicrotome (UC7, manufactured by Leica). The obtained thin section samples were stained using a vacuum staining apparatus (VSC4R1H, Philgen) in a RuO4 gas atmosphere at 500 Pa for 15 minutes, and STEM images were acquired using a scanning transmission electron microscope (JEM2800, JEOL). Under the above staining conditions, a difference in the degree of staining occurs between crystalline resin C and amorphous resin A, and the presence or absence of the matrix domain structure can be confirmed by the difference in contrast. In other words, crystalline resin C is stained with ruthenium more effectively than amorphous resin A, resulting in clearer contrast and easier observation. Because the amount of ruthenium atoms differs depending on the intensity of the staining, strongly stained areas have a higher concentration of these atoms, preventing electron beams from penetrating and appearing black in the observed image, while weakly stained areas allow electron beams to penetrate easily and appear white in the observed image. Yes. For observation, the acceleration voltage was set to 200kV, the STEM probe size to 1nm, the image size to 1024×1024 pixels, and the magnification to 30000, and dark-field (STEM-DF) images were acquired. Contrast and Brightness are adjusted so that the brightness in the luminance histogram from IMAGE J below is 150 when the portion with the maximum number of pixels mainly composed of resin is present.

[0091] If the brightness is between 140 and 160, you can adjust the brightness in Microsoft Photos. If the brightness is different from the above, change the staining conditions again and obtain the STEM image again. In this process, when selecting cross-sectional images of the toner, the weight-average particle size (D4) of the toner is measured using the measurement method described later. Then, 10 cross-sections of toner with a major axis diameter of 0.8 to 1.1 times D4 are arbitrarily selected. Furthermore, images are acquired in such a way that no more than one toner is contained within the field of view of a single image.

[0092] The luminance histogram is obtained by analyzing the STEM image of the toner cross-section obtained by the above method using the image processing software Image J (developed by Wayne Rashand). In other words, the luminance histogram is the luminance histogram obtained when the luminance spectrum of 256 levels is measured for the image obtained from the image analysis of the toner cross-section. The specific procedure is shown below.

[0093] First, convert the backscattered electron image to be analyzed to 8-bit using the Type option in the Image menu. Next, specify the analysis range to be limited to the area inside the toner contour. Here, the toner contour is defined as the interface between the visible light-curable resin and the toner cross-section. Clear the area outside the analysis range using the "Clear Outside" option in the Edit menu. In the Process menu, under Filters, set the Median diameter to 2.0 pixels to reduce image noise. Next, from the Image menu's Adjust section, select Threshold, set the bottom bar to 150, and select Apply. Display the List and calculate the white ratio from the number of zero pixels relative to the total number of pixels. This white ratio will be used as the area ratio of the domain (island). Next, using a similar binarized image, we select scale matching, Binary, and Watershed, and calculate the average area of ​​the white regions by taking measurements. This average area based on the number of white regions is then used as the average area based on the number of domains. For 10 STEM images of each toner cross-section, the same image analysis is performed to calculate the above values. The arithmetic mean of the obtained values ​​for each of the 10 images is taken as the physical property value of each toner.

[0094] (Confirmation of domain matrix structure) A domain-matrix structure is a state in which, for example, in a toner cross-sectional image, the matrix is ​​interconnected within the image, while the domains are separated by the matrix. In the STEM image of the toner cross-section, the black-stained and interconnected areas represent the matrix made of crystalline resin C. Furthermore, in the STEM image of the toner cross-section, the fragmented areas that are not stained black are considered to be domains of amorphous resin A. Regarding the matrix domain structure, specifically, in the 10 STEM images of the toner cross-section mentioned above, one or more domains separated by the matrix were observed, as described above. If this occurs, it is determined that the matrix domain structure is present.

[0095] <Measurement of weight-average particle size (D4) of toner> The weight-average particle size (D4) of the toner is calculated as follows. The measuring device used is the "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.), a precision particle size distribution analyzer using the pore electrical resistance method equipped with a 100 μm aperture tube. The measurement conditions are set and the measurement data is analyzed using the included dedicated software, "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.). The measurement is performed using 25,000 effective measurement channels. The electrolytic aqueous solution used for measurement is prepared by dissolving special grade sodium chloride in deionized water to a concentration of 1.0%, for example, "ISOTON II" (manufactured by Beckman Coulter, Inc.). Before performing measurements and analysis, configure the dedicated software as follows. In the dedicated software's "Change Standard Measurement Method (SOMME)" screen, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (manufactured by Beckman Coulter, Inc.). Press the "Measure Threshold / Noise Level Button" to automatically set the threshold and noise level. Also, set the current to 1,600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flush aperture tube after measurement". In the dedicated software's "Pulse to Particle Size Conversion Settings" screen, set the bin spacing to logarithmic particle size, the particle size bins to 256 particle size bins, and the particle size range from 2 μm to 60 μm. The specific measurement method is as follows:

[0096] (1) Place 200.0 mL of electrolytic solution into a 250 mL round-bottom glass beaker specifically designed for the Multisizer 3, set it on the sample stand, and stir the mixture with the stirrer rod at 24 revolutions per second in a counterclockwise direction. Then, use the "Aperture Tube Flash" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) Place 30.0 mL of the electrolytic solution into a 100 mL flat-bottomed glass beaker. Add 0.3 mL of a diluted solution of "Contaminon N" (a 10% aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) diluted three times by mass with deionized water as a dispersant. (3) Prepare an "Ultrasonic Dispersion System Tetra150" (manufactured by Nikko Bios Co., Ltd.) with an electrical output of 120W, which incorporates two oscillators with an oscillation frequency of 50kHz, with their phases shifted by 180 degrees. Add 3.3L of deionized water to the water tank of the ultrasonic disperser, and add 2.0mL of Contaminon N to this water tank. (4) Place the beaker from (2) above into the beaker fixing hole of the ultrasonic disperser and operate the ultrasonic disperser. Then, adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic solution inside the beaker is maximized. (5) While irradiating the electrolytic aqueous solution in the beaker described in (4) above with ultrasound, add 10 mg of toner particles to the electrolytic aqueous solution in small amounts and disperse them. Continue the ultrasonic dispersion treatment for another 60 seconds. During ultrasonic dispersion, adjust the water temperature in the tank to be between 10°C and 40°C as appropriate. (6) Using a pipette, add the electrolytic aqueous solution (5) containing the dispersed toner particles to the round-bottom beaker (1) placed in the sample stand, adjusting the concentration to 5%. Continue measuring until the number of particles reaches 50,000. (7) The measurement data is analyzed using the dedicated software provided with the device, and the weight-average particle size (D4) is calculated. Note that the "Average Diameter" on the "Analysis / Volume Statistics (Arithmetic Mean)" screen when the dedicated software is set to Graph / Volume % is the weight-average particle size (D4).

[0097] <Measurement of the content ratio of crystalline resin C in toner> In the method for separating crystalline resin C and amorphous resin A from the toner described above, chloroform The proportion of crystalline resin C in the toner is calculated based on the mass of the toner before dissolving in the toner and the mass of the separated crystalline resin C. [Examples]

[0098] The present invention will be described in detail below with reference to examples, but these examples are not intended to limit the present invention in any way. In the following formulations, parts are by mass unless otherwise specified. below, Examples 5-6, 16-20, and 23 are reference examples 5-6, 16-20, and 23, respectively. Let's assume that.

[0099] (Preparation of crystalline resin C-1) The following materials were added to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube under a nitrogen atmosphere. • Toluene 100.0 parts • Monomer composition 100.0 parts (The monomer composition shall be a mixture of the following monomers in the proportions shown below.) (Behenyl acrylate (monomer (a)) 80.0 parts) (Styrene 18.0 parts) (Methacrylic acid 2.0 parts) • Polymerization initiator t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 0.5 parts The reaction vessel was heated to 70°C while stirring at 200 rpm, and the polymerization reaction was carried out for 12 hours to obtain a solution in which the monomer polymer was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain crystalline resin C-1.

[0100] (Preparation of crystalline resins C-2 to C-10) Crystalline resins C-2 to C-10 were prepared in the same manner as in the preparation of crystalline resin C-1, except that the amount of monomer composition added was changed to that shown in Table 1. [Table 1]

[0101] <Example of Toner 1 manufacturing> [Manufacturing of toner using suspension polymerization method] (Manufacturing of toner particles 1) Methyl methacrylate (monomer (b)) 38.0 parts • Lauryl acrylate (monomer (c)) 20.0 parts • n-butyl acrylate 9.0 parts • Coloring agent: Carbon black 8.0 parts A mixture consisting of the above was prepared. The above mixture was placed in an attritor (manufactured by Nippon Coke Co., Ltd.) and dispersed using 5 mm diameter zirconia beads at 200 rpm for 2 hours to obtain a raw material dispersion.

[0102] On the other hand, in a container equipped with a high-speed stirring device homomixer (manufactured by Primix) and a thermometer, 735.0 parts of ion-exchanged water and 16.0 parts of trisodium phosphate (dodecahydrate) were added, and the mixture was heated to 60°C while stirring at 12000 rpm. Then, a calcium chloride aqueous solution, prepared by dissolving 9.0 parts of calcium chloride (dihydrate) in 65.0 parts of ion-exchanged water, was added, and the mixture was stirred at 12000 rpm for 30 minutes while maintaining the temperature at 60°C. Then, 10% hydrochloric acid was added to adjust the pH to 6.0, obtaining an aqueous medium in which an inorganic dispersion stabilizer containing hydroxyapatite was dispersed in water.

[0103] Next, the above raw material dispersion was transferred to a container equipped with a stirring device and a thermometer, and the temperature was raised to 60°C while stirring at 100 rpm. ·Crystalline resin C1 33.0 parts • Release agent 9.0 parts (Release agent: DP18 (Dipentaerythritol stearate wax, melting point 79°C, manufactured by Nippon Seiro Co., Ltd.) The above materials were added and stirred at 100 rpm for 30 minutes while maintaining a temperature of 60°C. Then, 5.0 parts of t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) were added as a polymerization initiator and stirred for another minute. Finally, the mixture was added to an aqueous medium being stirred at 12,000 rpm in the high-speed stirring device. Stirring was continued at 12,000 rpm for 20 minutes while maintaining a temperature of 60°C in the high-speed stirring device to obtain a granulated liquid. The granulated liquid described above was transferred to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube, and heated to 70°C while stirring at 150 rpm under a nitrogen atmosphere. The polymerization reaction was carried out at 150 rpm for 12 hours while maintaining the temperature at 70°C to obtain a toner particle dispersion. The obtained toner particle dispersion was cooled to 45°C while being stirred at 150 rpm, and then heat-treated for 5 hours while maintaining the temperature at 45°C. After that, while maintaining stirring, dilute hydrochloric acid was added until the pH reached 1.5 to dissolve the dispersion stabilizer. The solid components were filtered off, thoroughly washed with deionized water, and then vacuum-dried at 30°C for 24 hours to obtain toner particles 1.

[0104] (Preparation of Toner 1) For the above toner particles in a 1:98.0 ratio, silica microparticles (hydrophobized with hexamethyldisilazane, primary particle number average particle size: 10 nm, BET specific surface area: 170 m²) are used as an external additive. 2 2.0 parts of ( / g) were added and mixed using a Henschel mixer (manufactured by Nippon Coke Co., Ltd.) at 3000 rpm for 15 minutes to obtain Toner 1. The physical properties of the obtained Toner 1 are shown in Table 3.

[0105] <Manufacturing examples for toners 2-23> In the manufacturing example of toner 1, toner particles 2 to 23 were obtained by following the same procedure except for changing the type and amount of materials used and the reaction temperature as shown in Table 2. Furthermore, toners 2-23 were obtained by performing the same external additive procedure as with toner 1. The physical properties of the toners are shown in Table 3.

[0106] <Manufacturing examples of comparative toners 1-9> In the manufacturing example of toner 1, comparative toner particles 1 to 9 were obtained by keeping all other aspects the same except for changing the type and amount of materials used and the reaction temperature as shown in Table 2. Furthermore, the same external additive process as for Toner 1 was performed to obtain comparative toners 1-9. The physical properties of the toners are shown in Table 3.

[0107] [Table 2] In the table, butyl acrylate in other monomer 3 is n-butyl acrylate. HDDA represents hexanediol diacrylate.

[0108] [Table 3] Furthermore, in toners 1-23 and comparative toners 1-5 and 7-9, cross-sectional observation of the toner confirmed a matrix-domain structure consisting of a matrix made of crystalline resin C and domains made of amorphous resin A. The analysis described above revealed that crystalline resin C was present in toners 1-23 and comparative toners 1-5 and 7-9 in the same proportion as in the formulations described in Table 2. Furthermore, in toners 1-23 and comparative toners 1-9, each monomer unit forming crystalline resin C and each monomer unit forming amorphous resin A were present in the same proportion as in the formulations described in Table 2. The weight-average particle size D4 is in μm.

[0109] <Examples 1-23, Comparative Examples 1-9> Evaluation tests were conducted on toners 1-23 and comparison toners 1-9. The evaluation method and criteria are described below. The evaluation results are shown in Table 4.

[0110] <Toner Evaluation Method> <1> Low-temperature fixation For evaluating the low-temperature fixation properties of toner, a laser beam printer (commercial) is used as an image forming apparatus. A modified Canon LBP-7700C printer was used. The modifications included enabling operation even with the fuser unit removed and allowing the fuser temperature to be freely set. White paper (Red Label 90g paper) was used for printing the images. First, the toner was removed from the cartridge, cleaned with compressed air, and then 300g of the toner to be evaluated was filled into the cartridge. The cartridge was then left for 48 hours in an environment of 25°C and 40% RH. Under these conditions, it was installed in the cyan station of the printer, while dummy cartridges were installed in the other units. The evaluation was then carried out under the same conditions as above. Using the removed fuser, the process speed was set to 300 mm / s, and the initial temperature was set to 90°C. The temperature was then gradually increased by 5°C at each temperature while fixing the unfixed image described above, and fixed images were obtained at each temperature. The fixed image was visually inspected, and the lowest temperature at which no cold offset occurred was defined as the fixing start temperature. Low-temperature fixing performance was then evaluated according to the following criteria. [Evaluation Criteria] A: Fixation start temperature is 100°C or lower B: Fixation start temperature is between 105°C and 110°C. C: Fixing start temperature is between 115°C and 120°C. D: Fixing start temperature is 125°C or higher

[0111] <2> Heat resistant storage stability To evaluate the stability during storage, a heat resistance evaluation was conducted. 5g of toner was placed in a 100ml plastic cup and left for 3 days at a temperature of 50°C and a humidity of 40RH. The degree of toner aggregation was then measured as follows and evaluated according to the following criteria. As the measuring device, a "Powder Tester" (manufactured by Hosokawa Micron Corporation) was used, with a digital display vibration meter "DigiVibro MODEL 1332A" (manufactured by Showa Sokki Co., Ltd.) connected to the side of the vibration table. Then, on the vibration table of the Powder Tester, sieves with a mesh size of 38 μm (400 mesh), 75 μm (200 mesh), and 150 μm (100 mesh) were stacked in that order from bottom to top. The measurements were performed in a 23°C, 60% RH environment as follows. (1) The vibration amplitude of the vibration table was pre-adjusted so that the displacement value of the digital display vibration meter was 0.60 mm (peak-to-peak). (2) The toner that had been left for 10 days as described above was first left for 24 hours in an environment of 23°C and 60% RH, and 5.00 g of the toner was accurately weighed and gently placed on the top sieve with a mesh size of 150 μm. (3) After vibrating the sieves for 15 seconds, the mass of toner remaining on each sieve was measured, and the degree of cohesion was calculated based on the following formula. The evaluation results are shown in Table 4. Degree of aggregation (%) = {(Sample mass on a sieve with a mesh size of 150 μm (g)) / 5.00 (g)} × 100 +{(Sample mass on a sieve with a mesh size of 75 μm (g)) / 5.00(g)}×100×0.6 +{(Sample mass on a sieve with a mesh size of 38 μm (g)) / 5.00(g)}×100×0.2 [Evaluation Criteria] A: Cohesion level is less than 20% B: Cohesion level 20% or more but less than 25% C: Cohesion level between 25% and less than 30% D: Cohesion level of 30% or higher

[0112] <3> Hot offset resistance The highest temperature at which no hot offset was observed under the same conditions as for low-temperature fixing was defined as the maximum fixing temperature, and the difference between the maximum fixing temperature and the fixing start temperature was defined as the fixable region. The evaluation criteria for the fixable region were: It is as follows: A: The temperature at which hot offset does not occur is above the fixing start temperature + 60°C. B: The temperature at which hot offset does not occur is between the fixing start temperature and the fixing start temperature (50°C or higher, but less than 60°C). C: The temperature at which hot offset does not occur is between the fixing start temperature and the fixing start temperature (40°C or higher, but less than 50°C). D: The temperature at which hot offset does not occur is less than the fixing start temperature + 40°C.

[0113] <4> Load capacity The following evaluation was performed on image paper fixed at a temperature 20°C higher than the fixing start temperature. The image portion of the image paper was placed face down, and an unused sheet of paper (Canon Office Planner 64g / m²) was used. 2 500 sheets were placed on top of the fixing image paper, and then 500 sheets of the same type of unused paper were placed on top of the fixing image paper, sandwiching the fixing image paper. This was then left to stand in a constant temperature bath heated to 45°C for 72 hours before being removed from the constant temperature bath. The reflectance of the portion of unused paper that was in contact with the image paper was measured, and the reflectance of the portion of the unused paper that was not in contact with the image was subtracted to measure the color transfer of the image. Based on this, the image stackability was evaluated according to the following criteria. The reflectance was measured using a TC-6DS (manufactured by Tokyo Denshoku). A: The color transfer area has a density of less than 0.5%. B: The color transfer area has a density of 0.5% or more but less than 1.0%. C: The density of the color-transferred area is between 1.0% and less than 2.0%. D: The color density of the affected area is 2.0% or higher.

[0114] <5> Durable Kaburi To evaluate the low-temperature fixability of the toner, a laser beam printer (product name: LBP-7700C, manufactured by Canon) was used as the image forming apparatus. Under high temperature and high humidity conditions (temperature 32.5°C, humidity 80%RH), the initial toner amount on the evaluation paper was 0.40 mg / cm². 2 A solid image was created to achieve the desired result, and 3000 copies of the image with a print density of 2% were printed using the printer. After leaving it for one day, one image with a white background was printed out. The reflectance of the obtained image was measured using a reflectometer (Reflectometer Model TC-6DS, manufactured by Tokyo Denshoku Co., Ltd.). An amber filter was used as the filter for the measurement. The worst-case reflectance of the white area, Ds(%), and the reflectance of the transfer material before image formation, Dr(%), were used as the reflectance, and Dr-Ds was defined as the haze. The evaluation was performed according to the following criteria. The evaluation results are shown in Table 4. [Evaluation Criteria] A: Coverage is less than 1.0% B: Coverage is between 1.0% and less than 3.0% C: Overlap is between 3.0% and less than 5.0% D: Overlap rate is 5.0% or higher

[0115] [Table 4] In the table, the hot offset resistance value represents the value of XX in the evaluation criteria, which is "fixing start temperature + XX°C".

[0116] This disclosure relates to the following configuration. (Composition 1) A toner having toner particles with a binder resin, The binder resin contains amorphous resin A and crystalline resin C, In measuring the viscoelasticity of the toner, Storage modulus G' is 3.0 × 10⁻⁶ 7 Let T1 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 1.0 × 10⁻⁶. 7 Let T2 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 3.0 × 10⁻⁶. 6 When the temperature at which Pa is obtained is T3 [°C], The values ​​of T1, T2, and T3 are given by the following equations (1) and (2) T3 - T1 ≤ 10.0 (1) 50.0 ≤ T2 ≤ 70.0 (2) Satisfied, In the viscoelasticity measurement of the toner, the storage modulus G'(100) at 100°C was 1.0 × 10⁻⁶. 4 ~1.0×106 Pa, When the cross-section of the toner was observed using a scanning transmission electron microscope, In the cross-section, a matrix-domain structure having a matrix of crystalline resin C and domains of amorphous resin A was observed. The area ratio of the domain in the cross-section of the toner is 45-95 area%, The average area of ​​the domains in the cross-section of the toner, based on the number of domains, is 100 to 100,000 nm. 2 That is, A toner characterized by the following features. (Configuration 2) The toner according to configuration 1, wherein the area ratio of the domain in the cross-section is 60 to 90 area %. (Composition 3) The average area of ​​the aforementioned domain is 100 to 10,000 nm 2 The toner described in configuration 1 or 2. (Composition 4) The toner according to any one of configurations 1 to 3, wherein the crystalline resin C has monomer units (a) represented by the following formula (3). TIFF0007911892000011.tif56153 In formula (3), R 4 represents a hydrogen atom or a methyl group, and n represents an integer between 15 and 35. (Composition 5) The toner according to configuration 4, wherein the content of the monomer unit (a) represented by formula (3) in the crystalline resin C is 50.0 to 100.0% by mass. (Composition 6) The content of the crystalline resin C in the toner is 10.0 to 60.0% by mass. The toner specified in one of configurations 1-5. (Composition 7) The toner according to any one of configurations 1 to 6, wherein the amorphous resin A has monomer units (b) represented by the following formula (4). In formula (4), R 1 R represents a hydrogen atom or a methyl group. 5 This represents an alkyl group with 1 to 4 carbon atoms. TIFF0007911892000012.tif50153 (Composition 8) The aforementioned R 5 The toner according to configuration 7, wherein the toner is either a methyl group or a t-butyl group. (Composition 9) The toner according to any one of configurations 1 to 8, wherein the amorphous resin A has monomer units (c) represented by the following formula (7). In formula (7), R 2 represents a hydrogen atom or a methyl group, and m represents an integer between 7 and 35. TIFF0007911892000013.tif56153 (Composition 10) The crystalline resin C is a vinyl resin, The toner according to any one of configurations 1 to 9, wherein the amorphous resin A is a vinyl resin.

Claims

1. A toner having toner particles with a binder resin, The binder resin contains amorphous resin A and crystalline resin C, The amorphous resin A has a monomer unit (c) represented by the following formula (7), In the viscoelasticity measurement of the toner, the storage modulus G' was 3.0 × 10⁻⁶. ７ Let T1 [°C] be the temperature at which it reaches Pa, and let the storage modulus G' be 1.0 × 10⁻⁶. ７ Let T2 [°C] be the temperature at which Pa is obtained, and let the storage modulus G' be 3.0 × 10⁻⁶. ６ When the temperature at which Pa is reached is T3 [°C], T1, T2, and T3 are given by the following formulas (1) and (2): T3-T1≦10.0 (1) 50.0 ≤ T2 ≤ 70.0 (2) Satisfied, In the viscoelasticity measurement of the toner, the storage modulus G'(100) at 100°C was 1.0 × 10⁻⁶. ４ ~1.0 x 10 ６ Pa is, When the cross-section of the toner was observed using a scanning transmission electron microscope, In the cross-section, a matrix-domain structure having a matrix of crystalline resin C and domains of amorphous resin A is observed. The area ratio of the domain in the cross-section of the toner is 60 to 90 area %. The average area of ​​the domains in the cross-section of the toner, based on the number of domains, is 200 to 3,000 nm. ２ That is, A toner characterized by the following features. (In formula (7), R² represents a hydrogen atom or a methyl group, and m represents an integer from 7 to 35.)

2. The toner according to claim 1, wherein the crystalline resin C has monomer units (a) represented by the following formula (3). (In formula (3), R ４ (where n represents a hydrogen atom or a methyl group, and n represents an integer between 15 and 35.)

3. The toner according to claim 2, wherein the amorphous resin A has monomer units (b) represented by the following formula (4). (In formula (4), R １ represents a hydrogen atom or a methyl group, and R ５ represents an alkyl group having 1 to 4 carbon atoms.)

4. The toner according to claim 2, wherein the content of monomer unit (a) represented by formula (3) in the crystalline resin C is 50.0 to 100.0% by mass.

5. The toner according to claim 1, wherein the content of the crystalline resin C in the toner is 10.0 to 60.0% by mass.

6. The toner according to claim 1, wherein the amorphous resin A has monomer units (b) represented by the following formula (4). (In formula (4), R １ R represents a hydrogen atom or a methyl group. ５ (This represents an alkyl group with 1 to 4 carbon atoms.)

7. The aforementioned R ５ The toner according to claim 6, wherein the group is a methyl group or a t-butyl group.

8. The crystalline resin C is a vinyl resin, The toner according to claim 1, wherein the amorphous resin A is a vinyl resin.

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