JP2001117264A - Electrostatic developing toner and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner having a spherical toner form, which is hardly influenced by changes in the temperature, humidity or the like and which has uniform and stable electrification property, and to provide a method of producing that toner. SOLUTION: The electrostatic charge image developing toner contains a binder resin, a coloring agent and an organic compound showing >=3.0×10-4 N/cm surface tension when the compound is prepared into a 0.1% solution. The toner has <=3.0 ratio (G1/G2) of the proportion G1 (%) of a pigment exposed to the surface of the toner particles (the ratio of the nitrogen atom content (%) measured by X ray electron spectroscopy (XPS) to the amount of nitrogen atoms in the mol.wt. of one molecule of the pigment) to the proportion G2 (wt.%) of the pigment in the toner. The method of producing the electrostatic charge image developing toner includes processes of mixing a binder resin dispersion liquid, coloring agent dispersion liquid and dispersion liquid of a low softening point material with an org. compound to prepare a dispersion liquid of aggregates consisting of the binder resin and the coloring agent and then of heating and melting. The organic compound is preferably a fluorine-based surfactant and silicone oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge developing toner containing a binder resin and a colorant, which is used for developing an electrostatic latent image in electrophotography, electrostatic recording, and the like, and its production. About the method.

[0002]

2. Description of the Related Art Methods for visualizing image information via an electrostatic image, such as electrophotography, are currently used in various fields. In the electrophotographic method, an electrostatic image is formed on a photoreceptor by a charging and exposure process, and an electrostatic latent image is formed with a developer containing a toner for electrostatic charge development (hereinafter, sometimes simply referred to as “toner”). Is developed and visualized through a transfer step and a fixing step. As the developer used here, a two-component developer composed of a toner and a carrier, and a one-component developer using a magnetic toner or a non-magnetic toner alone are known. Usually, a kneading and pulverizing method is used in which a thermoplastic resin as a binder resin is melt-kneaded together with a releasing agent such as a pigment, a charging aid, and wax, cooled, finely pulverized, and further classified. If necessary, inorganic or organic fine particles may be added to the surface of the toner particles for the purpose of improving fluidity and cleaning properties. Although these methods can produce a toner having good characteristics, there are some problems described below.

In the usual kneading and pulverizing method, the shape of the toner particles and the surface structure of the toner are irregular, and the shape and the surface structure are slightly changed by changing the pulverizability of the material to be used and the conditions of the pulverization process. Although possible, intentional control of shape and surface structure is difficult.

[0004] In the kneading and pulverizing method, the range of materials that can be selected is also limited. Specifically, the dispersion composed of the binder resin and the colorant (resin colorant dispersion) must be sufficiently brittle and a material that can be finely pulverized by an economically usable manufacturing apparatus. However, if the resin colorant dispersion is made brittle to satisfy these requirements, finer toner particles are generated due to mechanical shearing force or the like applied in the developing machine, and the shape of the toner particles is hindered. Sometimes. Due to these effects, in the two-component developer, the charge deterioration of the developer due to the fine toner particles sticking to the carrier surface is accelerated. In the one-component developer, the particle size distribution is increased. Image quality is likely to be deteriorated due to scattering of toner or deterioration of developability due to change in shape of toner particles.

When a large amount of a release agent such as wax is internally added to form a toner, the release agent is exposed on the surface of the toner particles due to the combination with a thermoplastic resin as a binder resin. The impact is great. In particular, in the case of a combination of a binder resin whose elasticity is increased by a high molecular weight component and which is hardly pulverized and a brittle wax such as polyethylene, polyethylene is often exposed on the surface of the toner particles.
Although this is advantageous in the releasability at the time of fixing and the cleaning of the untransferred toner from the photoreceptor, since the polyethylene on the surface of the toner particles is easily transferred by mechanical force, the developing roll or the photosensitive Contamination easily occurs on the body and the carrier, leading to a decrease in the reliability of the toner for electrostatic charge development.

In addition, since the shape of the toner particles is irregular, even if a fluidity aid is added, sufficient fluidity may not be obtained. Is moved to the concave portion of the toner particles, whereby the fluidity decreases over time, or the fluidity aid is buried in the toner, thereby deteriorating the developability, transferability, and cleaning ability. Further, if the toner collected by cleaning after image formation is returned to the developing device and used again, the image quality is likely to be further deteriorated.
If the flow aid is further increased for the purpose of preventing these, black spots are generated on the photoreceptor and scattering of the aid particles occurs.

In recent years, as a means for intentionally controlling the shape and surface structure of toner particles, JP-A-63-28275 has been proposed.
No. 2, JP-A-6-250439 proposes a method for producing a toner by an emulsion polymerization aggregation method. In the emulsion polymerization aggregation method, generally, a resin dispersion is prepared by emulsion polymerization or the like, while a colorant dispersion in which a colorant is dispersed in a solvent is prepared, and these are mixed to correspond to a toner particle size. Aggregates are formed and fused by heating.
This is a manufacturing method in which toner is united.

However, in this method, since the surface of the toner particles and the inside thereof have the same composition, it is difficult to intentionally control the surface composition. Further, although a certain degree of chargeability can be obtained, it is difficult to obtain uniform and stable chargeability. As described above, in the electrophotographic process, the degree of exposure of the colorant on the toner surface is suppressed, or the toner is stably maintained under various mechanical stress conditions in order to maintain the performance. In addition, it is necessary to increase the surface hardness to improve the mechanical strength of the toner itself without impairing the fixing property, and to secure a sufficient charging property.

In recent years, there has been a high demand for higher image quality, and particularly in the formation of color images, there is a remarkable tendency to reduce the size of toner particles in order to realize high-definition images. But,
In the case of simple size reduction with the conventional particle size distribution, the presence of toner on the fine powder side significantly contaminates the carrier and the photoconductor, and the problem of toner scattering becomes prominent, simultaneously improving image quality and improving reliability. It is difficult to achieve. Therefore, means for sharpening the particle size distribution and for reducing the particle size is required.

In digital full-color copying machines and printers, color image documents are represented by B (blue), R (red),
(Green) color separation, and a latent image having a dot diameter of 20 to 70 μm corresponding to the original document is formed into Y (yellow), M (magenta), C (cyan), and Bk (black). It is developed and visualized using a subtractive color mixing action using a developer, but in this case, it is necessary to transfer a larger amount of developer and to cope with a smaller dot diameter compared to a conventional black and white machine. For these reasons, uniform chargeability, durability, toner strength, and sharpness of particle size distribution are becoming increasingly important issues.

Further, in consideration of the speeding up and energy saving of the copying machine and the printer, it is necessary to further improve the low-temperature fixability. From this point of view, the emulsion polymerization aggregation method having the steps of aggregation, fusion, and coalescence is suitable for producing a toner having a sharp particle size distribution and a small particle diameter, and the obtained toner has excellent characteristics.

However, the toner obtained by agglomeration, fusion, and coalescence tends to affect the chargeability due to the presence of a surfactant used as a dispersant and a colorant exposed on the surface of the toner particles, and is stable. There is a problem that it is not possible to maintain the improved chargeability. To solve this problem, see, for example,
JP-A-2-73277 and JP-A-3-35660 propose a method of coating the surface of toner particles with a resin layer. However, in the above method, it is possible to suppress the influence of the colorant on the chargeability.However, when the content of the pigment is large, the mechanical strength of the toner itself is increased or the toner particles are formed into a spherical shape. Cannot be transformed.

In Japanese Patent Application Laid-Open No. 64-62666, a charge control resin powder is adhered mechanochemically.
Although a method of microencapsulation is employed, the production of the toner using the aggregation method is complicated, and the mechanical strength of the toner is also a problem.

As described above, the shape of the toner particles is controlled to be spherical, and a uniform and stable chargeability and a high quality image can be formed without contaminating the photoreceptor or the carrier or deteriorating the fixability. At present, no electrostatic charge developing toner has been provided yet.

[0015]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, an object of the present invention is to provide a toner for electrostatic charge development having spherical toner particles, high chargeability, and uniform and stable chargeability. Another object of the present invention is to provide a method for producing a toner for electrostatic charge development, which can be controlled to be spherical and has uniform and sufficient charge stability.

[0016]

Means for Solving the Problems The present inventors have conducted intensive studies on a manufacturing method capable of improving the charging performance while controlling the spherical shape, and as a result, obtained the following knowledge. That is, (1) when a large amount of the colorant is present on the surface of the toner particles, the charge amount of the toner is liable to fluctuate with changes in the environment, stabilizing the chargeability, and hindering uniformity; It is found that there is a tendency that it is difficult not only to make the toner particles spherical but also to control the colorant to be present inside the toner particles.

The means for solving the above problems are as follows. That is, <1> the surface tension of a 0.1% solution of a toner for electrostatic charge development containing a binder resin and a colorant is adjusted to 3.
Containing an organic compound which can be 0 × 10 ⁻⁴ N / cm or less;
And the colorant is a pigment containing a nitrogen atom, and the content ratio of the pigment exposed on the surface of the toner particles is G ¹ [(%); X
Nitrogen atom content (%) measured by X-ray electron spectroscopy (XPS) / (ratio of atomic weight of nitrogen to molecular weight of one pigment molecule)] and pigment content ratio G ² (%;
The ratio (G ¹ / G ² ) of the toner for electrostatic charge development is 3.0 or less. In the above, the ratio of the atomic weight of nitrogen atoms in the molecular weight of one pigment molecule = (total atomic weight of nitrogen atoms in pigment molecules / molecular weight of pigment molecules).

The following <2> to <7> toners for electrostatic charge development are also preferred embodiments. <2> The electrostatic charge developing toner according to <1>, wherein the organic compound is a fluorinated surfactant or silicone oil. <3> The electrostatic charge development according to <2> or <2>, wherein the content of the organic compound is 0.002 to 1.5% by weight based on the amount (weight) of the binder resin contained in the toner particles. Toner.

<4> The electrostatic charge according to any one of <1> to <3>, wherein the content of the pigment containing a nitrogen atom is 4 to 15% by weight based on the content (weight) of the binder resin. This is a developing toner. <5> Sphericity of toner particles (SF1) is 100 to
125. The electrostatic charge developing toner according to any one of <1> to <4>, wherein the toner is 125.

<6> Volume average particle size distribution (GSDv)
Is the toner for electrostatic charge development according to any one of <1> to <5>, which is 1.28 or less. <7> The above <1 containing an inorganic metal salt as a flocculant.
> To <6>.

<8> A resin fine particle dispersion in which fine particles of a binder resin having a size of at least 1 μm or less are dispersed, a colorant dispersion in which a colorant is dispersed, and a softening substance dispersion in which a low softening point substance is dispersed. Mixing to include the compound, a step of preparing an aggregate dispersion containing an aggregate composed of fine particles of the binder resin and a colorant, and the aggregate dispersion at a temperature equal to or higher than the glass transition point of the binder resin. A method for producing a toner for electrostatic charge development, comprising at least steps of heating, fusing and coalescing.

<9> The method for producing a toner for electrostatic charge development according to <8>, wherein the organic compound is a fluorine-based surfactant or a silicone oil. > The method for producing a toner for electrostatic charge development according to <8> or <9>, wherein the colorant dispersion contains an organic compound.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The electrostatic charge developing toner of the present invention contains an organic compound having a surface tension of at least 3.0 × 10 ⁻⁴ N / cm when a 0.1% solution is prepared, And the content ratio G ^{1 of the} pigment exposed on the surface of the toner particles.
[(%); Nitrogen atom content (%) measured by X-ray electron spectroscopy (XPS) / (ratio of atomic weight of nitrogen to molecular weight of one pigment molecule)], and content ratio of pigment contained in toner The ratio (G ¹ / G ² ) to G ² (%; weight ratio) is set to 3.0 or less. In the method for producing a toner for electrostatic charge development of the present invention, a resin fine particle dispersion in which fine particles of a binder resin having at least 1 μm or less are dispersed, a colorant dispersion in which a colorant is dispersed, and a low softening point substance are used. A step of mixing the dispersed softening substance dispersion liquid so as to contain the organic compound and preparing an aggregate dispersion liquid containing an aggregate composed of fine particles of a binder resin and a colorant (hereinafter, referred to as a “mixing aggregation step”) And a step of heating and fusing and coalescing the aggregate dispersion at a temperature equal to or higher than the glass transition point of the binder resin (hereinafter, sometimes referred to as a “heat fusing step”). Comprising. Hereinafter, the electrostatic charge developing toner of the present invention will be described in detail, and through the description, the details of the manufacturing method will be clarified.

<Electrostatic Development Toner> The electrostatic development toner of the present invention comprises at least a binder resin and a colorant, and further contains an organic compound and a substance having a low softening point. Having the following components: In the present invention, a pigment containing a nitrogen atom is used as the colorant constituting the toner particles, and the amount of the pigment present on the surface of the toner particles to be formed is set in the following range. That is,

Content ratio of pigment exposed on the surface of toner particles G ¹ [(%); Nitrogen atom content (%) measured by X-ray electron spectroscopy (XPS) / (Nitrogen occupying one molecular weight of pigment molecule) Atomic ratio)] and the content ratio G ² (%; weight ratio) of the pigment contained in the toner (G ¹ / G ² ) to 3.0.
The following is assumed. Above all, the G ¹ / G ² value is preferably 1.5 or less. When the G ¹ / G ² value exceeds 3.0, the toner particles may be insufficiently spheroidized in some cases.

The content ratio G ¹ is such that, in a certain amount of toner, the pigment present on the surface of the toner particles,
The ratio (%) to the total amount of the pigment, and the amount (%) of nitrogen atoms that can be detected from the surface of the toner, measured by X-ray electron spectroscopy (XPS), The ratio can be obtained by dividing by the value obtained by the ratio (ratio) of the atomic weight of the atoms, that is, “the total of the atomic weights of the nitrogen atoms in the pigment molecule / the molecular weight of the pigment molecule”. That is, in the present invention, since a pigment containing a nitrogen atom is used as a colorant, the amount of the pigment that is exposed on the surface of the toner particles with respect to the total pigment content in the toner is determined by the amount of the nitrogen atom in the pigment. It can be judged from the amount.

The amount of nitrogen atoms detectable from the surface of the toner can be measured by X-ray electron spectroscopy (XPS), and is generally expressed as an index indicating the state of adsorbed molecules on the toner surface. As an apparatus using X-ray electron spectroscopy, for example, ESCA-lab-220iXL (excitation source: Mg
-Kα (300 W)) and can be measured by the following method.

That is, the sample (toner) is fixed to the sample holder and inserted into the XPS chamber. The degree of vacuum in the chamber is 133 × 10 ⁻⁹ [Pa] (10 ⁻⁹ [Torr]
r]. Mg-Kα was used as the excitation source, and the output was 300 W. Under the above conditions, the XPS spectrum was measured, and the composition ratio of the surface was determined from the peak area intensity of the detected element. The composition ratio of nitrogen was calculated from the peak area intensity of N1s. The surface composition ratio (element concentration) by XPS is obtained by correcting the spectral area intensity of each element by using a relative sensitivity factor unique to the device (a photoionization cross section in consideration of the electron escape depth and the device function), and calculating the percentage. Was.

In addition, the content G ² is the ratio of the pigment content (%; = weight of pigment used / toner) to the same amount of toner as in G ¹ with respect to all components (weight) of the toner. Weight × 100), and can be determined from the amount of pigment based on the total amount of components constituting the toner particles used in the production of the toner.

The toner for electrostatic charge development of the present invention is composed of toner particles having a spherical shape, and has a degree of sphericity (SF1) which is a measure of the shape of the toner particles in the following range. That is, from the viewpoint of image forming properties, the sphericity SF1 is preferably in the range of 100 to 125, and more preferably 100 to 120. The SF
If 1 exceeds 125, the resolution may decrease.

The degree of spheroidization SF1 is determined by determining the S
This is the average value of F1 and can be measured, for example, as follows. That is, an optical microscope image of the toner scattered on the slide glass is taken into an image analyzer (Luzex III, manufactured by Nireco Co., Ltd.) through a video camera, and SF1 ((peripheral length of toner particle) of each of 50 or more toner particles is used. ) ² / projected area)) and can be derived from their average. SF1 of each toner particle is SF1 =
(Maximum length of toner diameter) ² / (surface area of toner particles) × π
/ 4 × 100.

The average particle size of the toner particles in the electrostatic charge developing toner is preferably 2 to 9 μm, more preferably 3 to 8 μm. If the average particle size is less than 2 μm, the chargeability becomes insufficient and the developability may decrease. If the average particle size exceeds 9 μm, the image resolution may decrease. The average particle diameter can be easily measured using, for example, Coulter Counter TAII type (manufactured by Nikkaki Co., Ltd.), Multisizer II (manufactured by Nikkaki Co., Ltd.), or the like.

The volume average particle size distribution (GSDv) of the electrostatic charge developing toner of the present invention is preferably 1.28 or less, and more preferably 1.1 to 1.25. The volume average particle size distribution (GSDv) is, for example, a Coulter counter TAII type (Nikkaki Co., Ltd.)
) And Multisizer II (manufactured by Nikkaki Co., Ltd.) as described below.

That is, first, regarding the particle size distribution measured using the above measuring device, the divided particle size range (channel)
For each of the volume and the number, the cumulative distribution is drawn from the smaller diameter side. The 16% volume average particle diameter occupying 16% of the cumulative volume is defined as D16v, the 16% number average particle diameter is defined as D16p, and 50% of the volume is defined as D16p. 50% volume average particle diameter occupied by D5
The 0v, 50% number average particle diameter is defined as D50p. Further, similarly, the 84% volume average particle diameter and the 84% number average particle diameter are defined as D84v and D84p. The volume average particle size distribution (GSDv) is (D84v / D16v)
^The number average particle size distribution (GSDp) can be calculated from ^1/2 .
(D84p / D16p) ^1/2 can be calculated.

The absolute value of the charge amount of the toner for electrostatic charge development of the present invention is preferably 10 to 40 μC / g, and more preferably 15 to 40 μC / g.
35 μC / g is more preferred. The charge amount is 10 μC
If it is less than / g, background stain (fog) may easily occur, and if it exceeds 40 μC / g, the image density may be easily reduced. The ratio of the charge amount of the toner for electrostatic charge development in a high-temperature and high-humidity environment (summer) to the charge amount in a low-temperature and low-humidity environment (winter) is 0.5 to 1.
5 is preferable, and 0.7 to 1.3 is more preferable. If the ratio is out of the above range, the toner has a large environmental dependence on the charging property, and it may not be possible to stably maintain a constant charging state.

Hereinafter, each component of the electrostatic charge developing toner of the present invention will be described. (Organic compound) The toner for electrostatic charge development of the present invention has a surface tension of 3.0 × 10 ⁻⁴ N / cm when a 0.1% solution is prepared in addition to a colorant and a binder resin described below. Contains an organic compound that can be: The organic compound may be added at any timing of the mixing and aggregation step in the method for producing a toner for electrostatic charge development described below, and may be added before or after the formation of the aggregate, for example, as a colorant, as described below. The organic compound may be previously mixed in the pigment dispersion in which the pigment is dispersed, or may be mixed in the preparation of another resin fine particle dispersion or softening substance dispersion. In particular, an embodiment in which the organic compound is mixed in advance when preparing a pigment dispersion in which a pigment to be used as a colorant is dispersed is preferable, so that the pigment can be effectively adsorbed on the surface of the pigment particles.

As described above, by using an organic compound together with a pigment, the surface of the pigment is coated by adsorbing the organic compound on the particle surface of the pigment, thereby rendering the surface of the pigment hydrophobic. By using this hydrophobic pigment, the pigment itself can be retained inside the finally formed toner particles, and the amount of the pigment present on the surface of the toner particles can be reduced.

Accordingly, it is possible to suppress a change in the charging property due to a change in the environment, and to secure a uniform and stable charging property while having a sufficient charging property. In addition, when the pigment having the hydrophobic surface as described above is used, the shape of the toner particles of the formed toner for electrostatic charge development is easily made spherical.

Examples of the organic compound include a fluorinated surfactant and silicone oil. Particularly, from the viewpoint of adsorbability to a pigment, when a 0.1% solution of the organic compound is prepared, the surface tension of the solution is adjusted. Is selected to be 3.0 × 10 ⁻⁴ N / cm or less.

Examples of the fluorine-based surfactant include nonionics such as perfluoroalkylpolyoxyethylene ethanol, anionics such as perfluoroalkylcarboxylates, and cationics such as perfluoroalkylquaternary ammonium salts. Known ones.
As a commercially available product, for example, Florad FC manufactured by 3M
-129, Florard FC-171, Florard FC-
135 and the like. The silicone oil is not particularly limited, and includes, for example, dimethylpolysiloxane.

The 0.1% solution of the organic compound can be prepared by dissolving 0.1% of the total weight of the organic compound in purified water. It can be measured by appropriately selecting from known surface tension measuring methods such as (vertical plate method) and pendant drop method.

The content of the organic compound is 0.0 to the amount (weight) of the binder resin contained in the toner particles.
02 to 1.5% by weight, preferably 0.005 to 0.05
% Is more preferred. If the content is less than 0.002% by weight, the chargeability of the toner may not be sufficiently stabilized, and if it exceeds 1.5% by weight, aggregation may be unstable.

(Coloring Agent) As the coloring agent, a pigment containing a nitrogen atom is used, and the pigment can be appropriately selected from known pigments. As the yellow pigment, for example, Hansa Yellow 10G, Hansa Brilliant Yellow, Chrome Phthal Yellow 3G, Pigment Yellow 180,
Pigment Yellow 74, Benzidine Yellow G, Benzidine Yellow GR, Chrome Phthal Yellow Permanent Yellow NCG and the like. Examples of the red pigment include permanent red 4R, brilliantamine 3B, brilliantamine 6B, nabopalm carmine, first scarlet and the like.
Examples of the blue pigment include alkali blue lake, fast sky blue, ultramarine blue, phthalocyanine blue, and phthalocyanine green. These pigments can be used alone or as a mixture of two or more kinds, and further, can be used in a solid solution state.

The colorant is appropriately selected from the viewpoints of hue angle, chroma, lightness, weather resistance, OHP permeability, and dispersibility in toner. As the content of the coloring agent, the binder resin 1
The amount is preferably 4 to 15 parts by weight with respect to 00 parts by weight.

(Binder Resin) The binder resin is not particularly limited and may be appropriately selected from known polymers. Examples thereof include styrenes such as styrene, parachlorostyrene and α-methylstyrene, and methyl acrylate. , Ethyl acrylate, n-propyl acrylate, n-butyl acrylate,
Lauryl acrylate, 2-ethylhexyl acrylate,
Esters having a vinyl group such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate;
Vinyl nitriles such as acrylonitrile and methacrylonitrile; vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; polyolefins such as ethylene, propylene and butadiene; Such as a homopolymer of a monomer, a copolymer of a combination of two or more monomers, or a mixture thereof,

Further, non-vinyl condensed resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc., or mixtures of these with the above-mentioned vinyl resins, or vinyl resins in the coexistence thereof. Examples include a graft polymer obtained when polymerizing a monomer.

In the case of the vinyl monomer, emulsion polymerization or seed polymerization is carried out using an ionic surfactant or the like to prepare a resin fine particle dispersion. In addition, in the case of other resins, if the resin is soluble in a solvent that is oily and has relatively low solubility in water, the resin is dissolved in those solvents and is dissolved in water together with an ionic surfactant or a polymer electrolyte. Fine particles are dispersed by a dispersing machine such as a homogenizer, and then the solvent is evaporated by heating or reducing the pressure to prepare a resin fine particle dispersion.

The content of the binder resin in the toner is preferably from 50 to 90% by weight, and more preferably from 75 to 85% by weight.
Is more preferred.

(Low Softening Point Substance) It is preferable that the electrostatic charge developing toner of the present invention contains a low softening point substance for the purpose of improving the fixability at a low temperature. As the low softening point substance, a substance having a main maximum peak at 50 to 140 ° C. measured according to ASTM D3418-8 is preferable. If the main peak is less than 50 ° C., offset may easily occur during fixing,
When the temperature exceeds ℃, the fixing temperature becomes high, and smoothness cannot be obtained on the surface of the fixed image, which may impair the glossiness of the image.

The main maximum peak is, for example, DSC-
7 (manufactured by PerkinElmer). The temperature of the detection unit of the apparatus is corrected using the melting points of indium and zinc, and the calorific value is corrected using the heat of fusion of indium. For the sample, an aluminum pan was used, an empty pan was set as a control, and the measurement was performed at a heating rate of 10 ° C./min.

Examples of the low softening point substance include low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicones having a softening point upon heating; oleamide, erucamide, ricinoleamide, stearamide and the like. Fatty acid amides; carnauba wax, rice wax, candelilla wax, wood wax, jojoba oil and other vegetable waxes; beeswax and other animal waxes; montan wax, ozokerite,
Minerals such as ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax;
Petroleum-based waxes and modified products thereof.

The waxes may include an ionic surfactant,
Dispersed in water together with a polymer electrolyte such as a polymer acid or a polymer base, heated to a temperature higher than the melting point, and finely divided by a homogenizer or a pressure discharge type disperser that can be subjected to strong shearing. Can be created.

The content of the low softening point substance in the toner is preferably 5 to 30% by weight, more preferably 8 to 15% by weight.

(Other Components) As other components, for example, inorganic fine particles, inorganic metal salts, magnetic powder, charging aids, surfactants and the like can be used. In the toner for electrostatic charge development of the present invention, it is preferable to add the inorganic fine particles by a wet method. By adding the inorganic fine particles, the chargeability of the toner can be stabilized.

The inorganic fine particles include, for example, silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, etc., all of which can be used as an external additive on the surface of a toner, and ionic surfactants. , A polymer acid or a polymer base. After drying, inorganic particles such as silica, alumina, titania, and calcium carbonate, and resin particles such as vinyl-based resins and polyesters are dried in the same manner as ordinary toners for the purpose of imparting toner fluidity and improving cleaning properties. It can be added to the surface by shearing in a dry state and used as a flow aid or a cleaning aid.

In the toner for electrostatic charge development of the present invention,
It is preferable to add the inorganic metal salt for the purpose of a flocculant used in the flocculation process in the method for producing the electrostatic charge developing toner. Examples of the inorganic metal salt include aluminum sulfate, zinc chloride, and polyaluminum chloride. The amount of the inorganic metal salt used is preferably from 0.01 to 10% by weight based on the amount of the toner.

The magnetic powder may be contained for the purpose of imparting magnetism to the toner for electrostatic charge development. As the magnetic powder, a substance magnetized in a magnetic field is used, for example,
Examples include ferromagnetic powders such as iron, cobalt, and nickel, and compounds such as ferrite and magnetite.

For the purpose of further stabilizing the charging performance of the toner, a charging aid may be used. Examples of the charging aid include various commonly used charging aids such as a quaternary ammonium salt compound, a nigrosine compound, a dye composed of a complex of aluminum, iron, and chromium, and a triphenylmethane pigment. Can be Among them, a material that is hardly soluble in water is preferable from the viewpoint of controlling ionic strength that affects coagulation and stability at the time of aggregation and reducing wastewater contamination.

In the process for producing a toner for electrostatic charge development of the present invention, a surfactant may be added at the time of emulsion polymerization, dispersion and aggregation of a pigment, a binder resin or a release agent. Examples of the surfactant include anionic surfactants such as sulfate ester type, sulfonate type, phosphate ester type, and soap type; cationic surfactants such as amine salt type and quaternary ammonium salt type; Non-ionic surfactants such as polyethylene glycol-based, alkylphenol-ethylene oxide adduct-based, and polyhydric alcohol-based surfactants can be mentioned, and it is also effective to use them in combination.

In the mixing / aggregation step described below, the dispersion means used for preparing various dispersions can be appropriately selected from known ones such as a rotary shearing homogenizer, a ball mill having a media, a sand mill, and a dyno mill. .

<Manufacturing Method of Electrostatic Developing Toner> As described above, the manufacturing method of the electrostatic developing toner of the present invention includes at least a mixing and aggregating step and a heat fusing step.
In the mixing / aggregation step, the above-mentioned organic compound is introduced. That is, a resin fine particle dispersion in which at least 1 μm or less of binder resin particles are dispersed, a colorant dispersion in which a colorant is dispersed, and a softening substance dispersion in which a low softening point substance is dispersed are mixed so as to contain an organic compound. Then, after preparing an aggregate dispersion in which an aggregate composed of fine particles of a binder resin and a colorant is formed, the aggregate dispersion is heated to a temperature equal to or higher than the glass transition point of the binder resin and fused. And coalescing to obtain the toner for electrostatic charge development of the present invention.

Hereinafter, each step will be described. (Mixing / Aggregating Step) In the mixing / aggregating step, a resin fine particle dispersion in which fine particles of a binder resin of at least 1 μm or less are dispersed, a colorant dispersion in which a colorant is dispersed, and a dispersion in which a low softening point substance is dispersed Are mixed so as to contain an organic compound to prepare an aggregate dispersion liquid containing an aggregate composed of fine particles of a binder resin and a colorant. As described above, the organic compound may be added at any timing as long as it is included in the aggregate dispersion liquid, may be added at the time of preparing each dispersion liquid described above, or may be a plurality of dispersion liquids. It may be added to the liquid at the time of each preparation, or may be added after mixing each of the above dispersions. Among them, an embodiment in which an organic compound is mixed during the preparation of a pigment dispersion in which a pigment as a colorant is dispersed is preferable in that the pigment is effectively adsorbed on the surface of the pigment particles and the particle surface can be sufficiently hydrophobized. .

The colorant dispersion is obtained by dispersing a colorant in an aqueous medium by the above-described dispersing means. When the colorant dispersion is prepared in the presence of an organic compound, the method is as follows: The method may be a method of mixing a colorant dispersion liquid in which a colorant is dispersed and a solution of an organic compound, and adsorbing the organic compound on the particle surface of the colorant, or (b) the organic compound on the particle surface in advance. The method may be a method of dispersing the adsorbed colorant in an aqueous medium to obtain a colorant dispersion, or may be another method.

From the viewpoint of sufficiently adsorbing the organic compound on the surface of the colorant particles and increasing the hydrophobicity of the surface, the colorant dispersion is preferably left for a certain period of time after preparation. As a time for leaving it, 12 hours or more are preferable.

The softening substance dispersion is obtained by dispersing a low softening point substance in an aqueous medium, and preferably dispersing the low softening point substance into fine particles having a particle size of 0.1 μm or less by the above-mentioned dispersing means. I do. In this case, the dispersion diameter of the low softening point substance is preferably 50 to 1000 nm. The use of the low softening point substance can improve the fixability at low temperatures, but by setting the dispersion diameter within the above range, it is also possible to achieve improvements in charge stability and image durability. After preparing each dispersion as described above, they are mixed to form an aggregate in which the binder resin and the colorant are aggregated (aggregate dispersion).

(Heat Fusing Step) In the heat fusing step, the agglomerate is fused and coalesced by heating the aggregate dispersion obtained in the above step at a temperature equal to or higher than the glass transition point of the binder resin. After that, it is washed and dried to obtain toner particles.

That is, in the agglomeration process, after the first-stage matrix aggregation is formed and stabilized below the glass transition point,
As a step, a charging aid and then a resin fine particle dispersion are added, and then the temperature is raised to unite. When the low softening point substance is contained, it is preferable to add it before the addition in the second stage, from the viewpoints of chargeability and durability.

After completion of the coalescence by heating, an optional washing step
After the solid-liquid separation step and the drying step, the toner for electrostatic charge development of the present invention can be obtained. In the washing step, it is preferable to sufficiently perform replacement washing with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but among others, suction filtration, pressure filtration and the like are preferable from the viewpoint of productivity. The drying step is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration type fluidized drying and the like are preferable.

[0069]

[Composition of the pigment dispersion (1)]

 -Pigment dispersion liquid: 100 g (Pigment Yellow 180 (manufactured by Hoechst); 10%)-1% solution of Florad FC-129: 0.6 g (fluorinated surfactant; manufactured by 3M)

<Preparation of Electrostatic Development Toner (1)> The electrostatic charge development toner (1) of the present invention was prepared according to the following composition as follows. [Composition of toner particles] Resin fine particle dispersion liquid 260 g [Styrene-butyl acrylate-acrylic acid copolymer (copolymer ratio 82: 18: 2), Mw = 55000, Tg = 51 ° C.] The above-mentioned pigment dispersion liquid (1) 100 g Release agent dispersion liquid (HNP0190, manufactured by Nippon Seiro Co., Ltd.) 20 g Polyaluminum hydroxide 0.5 g (Paho2S, Asada Chemical Co., Ltd.) )

A round stainless steel flask was charged with the above composition (80% of the resin fine particle dispersion), added with Ultra Turrax T50 (manufactured by IKA), and mixed and dispersed.
The flask was heated to 48 ° C. with stirring in a heating oil bath. After holding at 48 ° C. for 30 minutes, the average particle diameter was measured using a Coulter counter (Multisizer II, manufactured by Coulter), and it was confirmed that an aggregate of about 4.5 μm was formed.

Further, the temperature of the heating oil bath is increased,
It was kept at 51 ° C. for 1 hour. When measuring the particle size,
It was confirmed that an aggregate of about 5.3 μm was formed.
Then, after adding the remaining 10% of the resin fine particle dispersion to the dispersion containing the aggregates, the average particle diameter was measured again and found to be 5.7 μm. After adding 40 g of sodium hydroxide solution (1N) to the dispersion containing the aggregates, the stainless steel flask was sealed and heated to 93 ° C. while stirring with a magnetic seal, and nitric acid (1N) was added.
And adjusted to pH 4 and maintained for 4 hours. Thereafter, the mixture was cooled to obtain a toner particle-containing liquid. When the average particle diameter of the toner particles was measured with a Coulter counter, it was 5.9 μm
Met.

The toner particles were filtered off from the toner particle-containing liquid obtained above, washed with a sodium hydroxide solution having a pH of 12.0, and then washed three times with ion-exchanged water. afterwards,
After 6 hours, the toner particles were freeze-dried, vacuum-dried for 24 hours, and sieved to obtain an average particle size of 5.9 μm.
m, GSDv = 1.21 and SF1 = 120 to obtain the toner (1) for electrostatic charge development of the present invention. Using the toner for electrostatic charge development (1), the amount (%) of nitrogen atoms present on the toner surface was measured by X-ray electron spectroscopy (XPS, manufactured by JEOL Ltd.), and the surface of the toner particles was measured. The content ratio of exposed pigment G ¹ [(%); the amount of nitrogen atoms (%) measured by X-ray electron spectroscopy (XPS) / (the ratio of the atomic weight of nitrogen to the molecular weight of one pigment molecule)] was determined. Was. Next, the G ¹
The ratio (G ¹ / G ² ) of the value to the content ratio G ² (%) of the pigment contained in the toner was determined to be 0.2.

Example 2 <Preparation of Pigment Dispersion (2)> The following components were mixed and allowed to stand for 2 to 3 days. [Composition of pigment dispersion liquid (2)]-Pigment dispersion liquid ... 100 g (Pigment Yellow 74 (manufactured by Dainichi Seika Kogyo Co., Ltd .; 10%)-1% solution of Florard FC-171 ... 1.0 g (Fluorine-based surfactant; manufactured by 3M)

<Preparation of Toner (2) for Electrostatic Development> With the following composition, the toner (2) for electrostatic development of the present invention was prepared as follows. [Composition of Toner Particles] Resin fine particle dispersion liquid 210 g (styrene-butyl acrylate-acrylic acid copolymer, Mw = 80000, Tg = 53 ° C.) Pigment dispersion liquid (2) 100 g Molding agent dispersion liquid (HNP0190, manufactured by Nippon Seiro Co., Ltd.) 20 g Aluminum chloride 0.7 g

The above composition (90% of the resin fine particle dispersion) was placed in a round stainless steel flask, and Ultra Turrax T50 (manufactured by IKA) was added and mixed and dispersed.
The flask was heated to 50 ° C. while stirring in an oil bath for heating. After holding at 50 ° C. for 30 minutes, the average particle diameter was measured by the Coulter counter used in Example 1, and it was confirmed that an aggregate of about 5.4 μm was formed. Thereafter, after adding the remaining 10% of the resin fine particle dispersion to the dispersion containing the aggregates, the average particle diameter was measured again and found to be 6.0 μm. Thereafter, an anionic surfactant (Neogen RK,
After adding 3 g of Daiichi Kogyo Seiyaku Co., Ltd.), the stainless steel flask was sealed, heated to 97 ° C. while continuing to stir using a magnetic seal, and held for 8 hours. Thereafter, the mixture was cooled to obtain a toner particle-containing liquid. When the average particle diameter of the toner particles was measured by a Coulter counter, it was 5.9.
μm.

The toner particles were separated by filtration from the toner particle-containing liquid obtained above, washed with a sodium hydroxide solution having a pH of 12.0, and then washed three times with ion-exchanged water. Thereafter, the toner particles are freeze-dried, and after 6 hours, vacuum drying is performed for 24 hours.
After performing for an hour, the mixture was further sieved and the average particle diameter was 5.9 μm.
m, GSDv = 1.24 and SF1 = 119 to obtain a toner (2) for electrostatic charge development of the present invention. Using this electrostatic charge developing toner (2), G ¹ calculated in the same manner as in Example ¹
The / G ² value was 0.8.

Example 3 <Preparation of Pigment Dispersion Liquid (3)> The following components were mixed and left for 2 to 3 days. [Composition of pigment dispersion liquid (3)]-Pigment dispersion liquid ... 100 g (ECR-184, manufactured by Dainichi Seika Kogyo Co., Ltd .; 10%)-1% solution of Florad FC-129 ... 0.3 g (Fluorine-based surfactant; manufactured by 3M)

<Preparation of Toner (3) for Electrostatic Development> The toner (3) for electrostatic development of the present invention was prepared according to the following composition and as shown below. [Composition of Toner Particles] Resin fine particle dispersion liquid 210 g (styrene-butyl acrylate-acrylic acid copolymer, Mw = 55000, Tg = 52 ° C.) Pigment dispersion liquid (3) 100 g Molding agent dispersion liquid (HNP0190, manufactured by Nippon Seiro Co., Ltd.) 20 g Ferric chloride 1.5 g

A round stainless steel flask was charged with the above composition (90% of the fine resin particle dispersion), added with Ultra Turrax T50 (manufactured by IKA), and mixed and dispersed.
The flask was heated to 51 ° C. while being stirred in a heating oil bath. After holding at 51 ° C. for 30 minutes, the average particle diameter was measured by the Coulter counter used in Example 1, and it was confirmed that an aggregate of about 5.4 μm was formed. After adding the remaining 10% of the resin fine particle dispersion to the dispersion containing the aggregate, the average particle diameter is measured again.
It was 0 μm.

After adding 35 g of sodium hydroxide (1N) to the dispersion containing the aggregates, the mixture was heated to 93 ° C.
The pH was adjusted to 3.8 with nitric acid (1N) and maintained for 4 hours. Thereafter, the mixture was cooled to obtain a toner particle-containing liquid. The average particle size of the toner particles measured by a Coulter counter was 5.9 μm.

The toner particles were separated from the toner particle-containing liquid obtained above by filtration, washed with a sodium hydroxide solution having a pH of 12.0, and then washed three times with ion-exchanged water. Thereafter, the toner particles are freeze-dried, and after 6 hours, vacuum drying is performed for 24 hours.
After conducting for a time, the mixture was further sieved to have an average particle size of 5.9 μm,
The toner (3) of the present invention having GSDv = 1.22 and SF1 = 117 was obtained. G ¹ / G ² calculated in the same manner as in Example 1 using the electrostatic charge developing toner (3).
The value was 1.5.

(Comparative Example 1) Pigment dispersion liquid of Example 1 (1)
Except that no fluorine surfactant was used in the preparation of
The same component composition as in Example 1 was used. After adding and mixing and dispersing Ultra Turrax T50 (manufactured by IKA) to the round stainless steel flask, the flask was heated to 48 ° C. with stirring in a heating oil bath. After holding at 48 ° C. for 30 minutes, the average particle diameter was measured by the Coulter counter used in Example 1, and it was confirmed that an aggregate of about 5.5 μm was formed. Here, after adding the remaining 10% of the resin fine particle dispersion, the average particle diameter was measured. As a result, it was confirmed that an aggregate of about 5.8 μm was formed.

Thereafter, 40 g of sodium hydroxide (1N) was added to the dispersion containing the aggregates, and then the stainless steel flask was sealed and heated to 93 ° C. for 4 hours while continuing to stir using a magnetic seal. Held. Thereafter, the mixture was cooled to obtain a toner particle-containing liquid. When the average particle diameter of the toner particles was measured by a Coulter counter, 5.8 μm was obtained.
m.

The toner particles were separated from the toner particle-containing liquid obtained above by filtration, washed with a sodium hydroxide solution having a pH of 12.0, and then washed three times with ion-exchanged water. Then, after freeze-drying for 6 hours, vacuum drying was carried out for 24 hours, and then sieved to obtain an average particle size of 5.8 μm, GSDv =
1.22, an electrostatic charge developing toner (4) having an SF1 of 125 was obtained. Using this electrostatic charge developing toner (4),
The G ¹ / G ² value calculated in the same manner as in Example 1 was 5.0.

Comparative Example 2 Pigment Dispersion of Example 2 (2)
Except that no fluorine surfactant was used in the preparation of
The same component composition as in Example 1 was used. After adding and mixing and dispersing Ultra Turrax T50 (manufactured by IKA) to the round stainless steel flask, the flask was heated to 50 ° C. for 1 hour while stirring the flask in an oil bath for heating. When the average particle diameter was measured using the Coulter counter used in Example 1, it was confirmed that an aggregate of about 5.4 μm was formed. Here, after adding the remaining 10% of the resin fine particle dispersion, the average particle diameter was measured. As a result, it was confirmed that an aggregate of about 5.8 μm was formed.

Thereafter, an anionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku Co., Ltd.) was added to the dispersion containing the aggregates.
After addition of 3 g, the stainless steel flask was sealed and heated to 97 ° C. while stirring with a magnetic seal, and held for 8 hours. Thereafter, the mixture was cooled to obtain a toner particle-containing liquid. The average particle size of the toner particles measured by a Coulter counter was 6.0 μm.

The toner particles were filtered off from the toner particle-containing liquid obtained above, washed with a sodium hydroxide solution having a pH of 12.0, and then washed three times with ion-exchanged water. Then, after freeze-drying for 6 hours, vacuum drying was performed for 24 hours, followed by further sieving to obtain an average particle size of 6.0 μm and GSDv =
As a result, an electrostatic charge developing toner (5) having a ratio of 1.25 and SF1 = 124 was obtained. Using this electrostatic charge developing toner (5),
The G ¹ / G ² value calculated in the same manner as in Example 1 was 4.0.

<Evaluation of Charging Property> The electrostatic charge developing toners (1) to (3) of the present invention obtained above and the electrostatic charge developing toners (4) to (5) were used as follows. The electrostatic image developers (1) to (3) and the electrostatic image developers (4) to (5) of the present invention were prepared, and their charging characteristics were evaluated. The numbers of the electrostatic charge developing toner and the electrostatic charge image developer are the same.

That is, the obtained electrostatic charge developing toner (1)
For each of (5) to (5), 2.0 g of hydrophobic silica (TS720: manufactured by Cabot) was added to 50 g thereof, and blended by a sample mill. This was weighed so that the toner concentration in a ferrite carrier having an average particle diameter of 50 μm coated with 1% of methacrylate (manufactured by Soken Chemical Co., Ltd.) was 5%, and stirred with a ball mill for 5 minutes.
By mixing, developer (1) to (5) for electrostatic charge development was prepared. The number in parentheses of the obtained developer for electrostatic charge development is
It should be the same as the number of the electrostatic charge developing toner. About the obtained developer for electrostatic charge development, as follows:
The environmental dependence of the charge amount and the charge stability by continuous processing were evaluated.

(Environmental Dependency) Developer for Electrostatic Development (1)
In each of (5) to (5), under a low-temperature and low-humidity environment of 10 ° C. and 15% RH, and in a high-temperature and high-humidity environment of 28 ° C. and 90% RH, the respective toners for electrostatic charge development are sequentially copied to a copier (Able).
1302α modified MC, manufactured by Fuji Xerox Co., Ltd.), and the initial charge amount of the developer on the magnetic roll was measured using a blow-off tribometer (manufactured by Toshiba Chemical Corporation). From this measurement result, the difference ΔE (μC / g) between the charge amounts in both environments was determined and evaluated according to the following criteria. The results of the measurement and evaluation are shown in Table 1 below. [Evaluation Criteria] ○: ΔE ≦ 5 Δ: 5 <ΔE <10 ×: 10 ≦ ΔE

(Charging Stability) For each of the electrostatic charge developing agents (1) to (5), each of the electrostatic charge developing agents is sequentially placed in an environment of 10 ° C. and 15% RH. After measuring the initial charge amount of the developer on the magnetic roll in the same manner as described above, a running test of 10,000 sheets was performed for each. After the test, the charge amount of the developer on the magnetic roll after processing 10,000 sheets was measured in the same manner as above, and the difference ΔE (μC
/ G) and evaluated according to the above criteria. The results of the measurement and evaluation are shown in Table 1 below.

[0093]

[Table 1]

From the results shown in Table 1 above, the amount of the pigment (G ¹ / G ² ) exposed on the surface of the toner particles by adsorbing a fluorine-containing surfactant or silicone oil on the surface of the particles was set within the range specified in the present invention. According to the developer for electrostatic charge development containing the toners (1) to (3) for electrostatic charge development of the present invention, spherical toner particles can be easily obtained, and the charge change width due to the change in the temperature and humidity environment or the continuous processing can be obtained. It was small and excellent in chargeability, and also had sufficient charge stability. On the other hand, an electrostatic charge developing toner including the toners (4) and (5) for electrostatic charge development, which does not use an organic compound such as a fluorine-based surfactant and the amount of the exposed pigment on the surface of the toner particles does not fall within the range specified in the present invention. In the case of the developer for use, the charge amount was significantly reduced particularly in a high-temperature and high-humidity environment, and the change amount of the charge amount before and after the continuous processing was large, so that a uniform and stable charge amount could not be maintained.

[0095]

According to the present invention, it is possible to provide a toner for electrostatic charge development in which toner particles are spherical, have high chargeability, and have uniform and stable chargeability. Further, according to the method for producing a toner for electrostatic charge development of the present invention, it is possible to provide a toner for electrostatic charge development which can be controlled to be spherical and has uniform and sufficient charge stability.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomoko Watanabe 1600 Takematsu, Minami Ashigara City, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Masaaki Suwabe 1600 Takematsu Minami Ashigara City, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Shuji Sato 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture F-Xerox Co., Ltd. F-term (reference) 2H005 AA06 AA15 AA21 AB03 CA11 CA12 CA21 CA23 EA05 EA07 EA10

Claims (2)

[Claims] 1. An electrostatic charge developing toner containing a binder resin and a colorant, containing an organic compound capable of reducing the surface tension to 3.0 × 10 ⁻⁴ N / cm or less when a 0.1% solution is prepared. And the colorant is a pigment containing a nitrogen atom,
Content ratio G of pigment exposed on the surface of toner particles
¹ [(%); Nitrogen atom content (%) measured by X-ray electron spectroscopy (XPS) / (ratio of nitrogen atom weight to molecular weight of one pigment molecule)] and pigment content in toner The ratio (G ¹ / G ² ) of the ratio G ² (%; weight ratio) is 3.0.
A toner for electrostatic charge development, characterized in that: 2. An organic compound comprising: a resin fine particle dispersion in which binder resin fine particles of at least 1 μm or less are dispersed; a colorant dispersion in which a colorant is dispersed; and a softening substance dispersion in which a low softening point substance is dispersed. And a step of preparing an aggregate dispersion including an aggregate composed of binder resin fine particles and a colorant, and heating the aggregate dispersion at a temperature equal to or higher than the glass transition point of the binder resin. And a step of fusing and coalescing.