JPS6165261A - Capsule toner - Google Patents

Abstract

PURPOSE:To obtain a capsule toner which exhibits excellent developability and transferability under high humidity by forming a shell contg. the resultant product of reaction of a polymer or copolymer reactable with reaction activity modified polyorganosiloxane and reaction activity modified polyorganosiloxane having a reactive functional group. CONSTITUTION:The shell of the capsule toner constituted of the core material and the shell coating the core material contains the resultant product of reaction of the polymer or copolymer reactable with the reaction activity modified polyorganosiloxane and the reaction activity modified polyorganosiloxane having the reactive functional group. The undesirable tendency to make ununiform the electrostatic chargeability of a toner such as the poor affinity to other resins owing to the high release property of polyorganosiloxane and the high transferability owing to the low surface tension thereof are suppressed and the high fluidity, non-tackiness and moisture resistance are provided to the toner by securing the polyorganosiloxane to the surface layer of the toner. The excellent developability and transferability are exhibited even in high- humidity environment and the welding of the toner to a member in contact with the toner is suppressed.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a capsule toner used to develop an electrical latent image in electrophotography, electrostatic printing, etc. 1' to capsule toner suitable for
A.

[Prior Art] Conventionally, as an electrophotographic method, U.S. Patent No. 2,297,89
As described in the specification of No. 1, Japanese Patent Publication No. 42-23910, Japanese Patent Publication No. 43-24748, etc., many people? Jr. is known, but generally IT1 uses a photoconductive material to generate electrical H3 onto a photoreceptor by various means.
After forming an image and then developing the latent image using toner and optionally transferring the toner image to a transfer material such as paper,
Copies are obtained by fixing by heat, pressure, or solvent vapor.6 The developed toner image is fixed by heating and melting it with an infrared heater or a heated roller to fuse and solidify it to the support. However, a pressure fixing method using a rigid roller has been proposed for reasons such as preventing fire hazards, reducing power consumption, and simplifying the fixing device.

However, with conventional pressure fixing toner, the development operation
In order to withstand various forces and to prevent caking during storage, a material that can be fixed at a slightly higher pressure was selected.As a result, the fixing support such as paper becomes transparent and does not wrinkle. It has problems in terms of quality, such as bunching, curling, and becoming glossy.

As a method for improving these conventional pressure fixing toners, several proposals have been made for pressure fixing toners that can be fixed at a lower pressure and have high durability and stability.

For example, Japanese Patent Publication No. 54-8104 (U.S. Patent No. 37
There are capsule-type toners with a soft material core and hard resin ridges, as seen in Japanese Patent Application No. 88994), and soft resin warm Iα core capsule toners. Disadvantages of pressure-fixable toners, such as adhesion to developing sleeves and photoreceptor surfaces, have not necessarily been resolved, and it has been found that shell materials suitable for encapsulation have properties desired as electrophotographic materials. However, there are few that exhibit stable charging characteristics, especially in humid environments ranging from low humidity to high humidity.
It has not yet been put into practical use.

[Problem that the invention attempts to solve] The present invention has been made in view of the above points.

An object of the present invention is to provide a capsule toner that solves the above-mentioned drawbacks.

The object of the invention is to provide a capsule toner that exhibits excellent developability and transferability even in a high humidity environment.

A further object of the present invention is to provide a capsule toner that suppresses toner adhesion to members that come into contact with the toner, such as a photoreceptor, a developing sleeve, a carrier, and a pressure roller.

A further object of the present invention is to provide a pressure-fixable capsule toner that exhibits good fixability at a lower pressure than conventional toners and also has excellent durability and stability.

[Means and effects for solving the problems] According to the present invention, in a capsule toner comprising a core material and an outer shell covering the core material, the outer shell reacts with a reactively modified polyorganosiloxane. (A polymer or copolymer capable of
A capsule toner containing a reaction product of a reactively modified polyorganosiloxane having a reactive functional group is provided.

The key point of the present invention is to fix the polyorganosiloxane to the surface layer of the toner, thereby eliminating the poor compatibility with other resins due to the high releasability of the polyorganosiloxane, and the low 1. % It is possible to suppress bad habits such as high migration caused by surface tension that make toner charging properties uneven, and to give toner high 1,1 fluidity, non-adhesiveness, and moisture resistance. be.

A method for fixing polyorganosiloxane to the toner surface layer is to include reactive activity 1 as a functional group in the polyorganosiloxane chain, and to cause so-called modified silicone oil to react with the functional group of the resin of the shell material. It is done.

Reactively modified silicone oils include amino-modified silicone oil, epoxy-modified silicone oil, alcohol-modified silicone oil, carboxylic acid-modified silicone oil, mercapto-modified silicone oil, and incyanate-modified silicone oil. group, incyanate group, and amino group. Among them, amine-modified silicone oil is preferred because it has appropriate reactivity.

Amino-modified silicone oils include those with pendant amine groups attached to polyorganosiloxane chains, such as Wa (A) or structure (B), or diamines with 7-mino groups at both ends, such as structure (C). Types can be used.

Amino-modified silicone oils having these structures are commercially available and can be easily obtained.

The polymer or copolymer (hereinafter abbreviated as "reactive poly") that can react with the reaction-activity-modified polyorganosiloxane described in 1- above is a polymer or copolymer that can be reacted with the reaction-activity-modified polyorganosiloxane when the reaction-activity-modified silicone oil is a 7-mino-modified silicone oil. When the reactively modified silicone oil is an epoxy-modified silicone oil, a reactive polymer containing a hydroxyl group, a carboxyl group, an acid anhydride rli position, an acid anhydride group, an amine group, an epoxy group, an acid halide group, an isocyanate group, etc. is used. When the reactively modified silicone oil is an alcohol-modified silicone oil, a reactive polymer containing an epoxy group, an acid halide, an incyanate group, etc. is used; In the case of acid-modified silicone oil, a reactive polymer containing epoxy groups, isocyanate groups, etc. is used; in the case of mercapto-modified silicone oil, a reactive polymer containing epoxy groups, isocyanate groups, etc. is used: isocyanate-modified silicone In the case of oil, it is an amine group.

- is used as a reactive polyester containing hydroxyl groups, carboxyl groups, etc.

Among the above-mentioned combinations of the reaction-activated modified polyorganosiloxane and the reactive polymer, a combination of an amine-modified silicone oil and an acid anhydride, and a copolymer containing maleic anhydride in the unit of 1,000 units is particularly preferred. be. The amino group and the acid anhydride intermediate have good reactivity, and
It is easy to handle because it does not easily undergo hydrolysis and lose its reaction activity unlike acid chlorides and incyanates.

Polymers or copolymers containing maleic anhydride as one unit include acrylic acid, methacrylic acid and/or styrene, copolymers with α-olefins, natural resin-modified maleic resins, maleic acid, etc. Modified phenolic resins and the like are known, and any of them can be preferably used.

The method for producing the capsule toner of the present invention can utilize Katsura's known encapsulation techniques.9 For example, spray drying method, interfacial polymerization method, coacervation method, phase separation method, 1n-situ method, etc. , U.S. Patent No. 3,
No. 338,981 IrJ1 Specification, No. 3.328,84
Methods such as those described in Specifications No. 8, Shim 3 , 502, and 582 can be used.

The reactive polymer and reactively modified polyorganosiloxane can be present in the shell material solution from the beginning of the encapsulation reaction, but the heat source of the shell material containing the reactive polymer surrounds the core, and to some extent Although the shape is adjusted,
When the shell material is still in a swollen state, or after the shell has been formed, the shell material is re-injected into a liquid that disturbs it. The reaction-activated modified polyorcasiloxane can be introduced into the system and reacted, and these methods can produce greater effects with fewer doses.

The reactive polymer can be used in excess of the reactively modified polyorganosiloxane and can be used within a range that does not change the physical properties of the desired toner. is effective at only 0.01% in nail thickness, and 0.1%
A sufficient effect can be obtained with the above steps. However, it is economical to use more than 5% of resin (IJ-?) Generally known resins can be used as the shell material, such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, etc. , styrene-butadiene copolymer, styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, and other polymers or copolymers of styrene or its substituted products; epoxy resins, polyester resins, acrylic resins,
Acrylic 0 = tolyl resin, xylene resin, polyurethane, polyurea, melamine resin, polyamide resin, ionomer resin, furan resin, ketone resin, terpene resin,
Phenol-modified terpene resin, rosin, rosin-modified pentaerythritol ester, natural resin-modified phenolic resin, coumaron indene resin, alicyclic hydrocarbon resin, petroleum resin.

Phthalic acid vinegar, ugly cellulose, starch graft nail coalescence, polyvinyl butyral, polyvinyl alcohol, polyvinylpyrrolidone, polyvinylpyridine, polyvinylidene chloride,
Polyvinylidene fluoride, polyvinylimidazole, polypyrrole, chlorinated paraffin, wax, fatty acids, etc. can be used in combination with Sino-German or Jl'lj. Furthermore, styrene-maleic anhydride copolymers, natural resin-modified maleic acid resins, maleic-modified phenol resins, and the like can be used alone or in combination.

In the case of a solid core, the core material used in the present invention includes low molecular weight fast polyethylene wax, paraffin wax,
Fatty alcohols and their esters, metal soaps, fatty alcohols, polyhydric alcohols, and (1) their metal salts and (1)
! Chemicals, fluorides, amides, bisamides, 11M products are sold as microcrystalline wax and amide wax, and natural products include castor wax, wood wax, beeswax, Karnahe wax, and rice wax. , soft materials such as montan wax, and releasable materials such as polypropylene, polyvinyl fluoride, polyfluoroethylene, and polytetrafluoroethylene.

Further, to improve adhesion, ethylene-based co-ester polymers such as ethylene-vinyl acetate, ethylene-vinyl ether, etc. can be used in combination. To prevent the elongation of the fixed image, the addition of a releasing substance improves the surface slippage, and the addition or use of sticky substances such as rubbery substances such as cyclized rubber and polynotadiene is also recommended. effective.

In the case of a liquid core, a general-purpose resin can be used in addition to the double resin. In the case of liquid cores, it is important to maintain a suitable level of viscosity, as soaking, bleeding, blending, and repellency into the fixing paper or synthetic paper slag, such as transparent range, will affect the quality of fixing. It is. For this purpose, it is effective to use a mixture of high boiling point solvents, or to use liquid polymers such as polybutene, plasticizers such as phthalic acid diesters, and unsaturated drying oils such as soybean oil and castor oil.

As the coloring agent contained in the core material of the capsule toner of the present invention, known dyes and pigments can be used. Examples include various carbon blacks, aniline blanks, naphthol yellow, molybdenum orange, rhodamine lake, alizarin lake, methyl violet lake, phthalocyanipple, nigrosine methylene blue, rose bengal, and quinoline yellow.

When the capsule toner of the present invention is used as a magnetic toner, magnetic powder can be contained in the core material.

Examples of magnetic powder include ferromagnetic elements such as iron, cobalt, ferromagnetic elements, and manganese, and alloys containing these elements such as magnetite and ferrite.

Compounds, etc. This magnetic powder may also be used as a coloring agent. The content of this magnetic powder is 10% of all the resin in the core material.
It is 15 to 70 tonne parts per 0 parts by weight.

Furthermore, the toner of the present invention may be mixed with carrier particles such as iron powder, Gates beads, nickel powder, ferrite powder, etc., as required, and used as a developer for electrical latent images.

In addition, it can be used in combination with hydrophobic colloidal silica powder for the purpose of improving the flowability of the powder, and abrasive particles such as cerium oxide to prevent toner sticking.

[Example] The present invention will be described in detail below with reference to Examples.

Example 1 The core material was prepared by melt-mixing 40 parts by weight of polyethylene wax, 13 Qli parts of paraffin wax (155°p), and 80 ffi parts of magnetite at 150°C, granulating the mixture with a spray dryer, and then determining the particle size by dry classification. But, 5p,
A spherical product with a diameter of 1I to 20 JLm was obtained.

100 parts by weight of the core particles were mixed with 15 parts by weight of styrene-maleic anhydride (80:20) copolymer, amino-modified silicone oil [trade name: X-22-3880 (amines i 8800, structure in the specification) B) Equivalent): Shin-Etsu Chemical E-gyo] 0.3 parts by weight of IPA/MEK (1:1)
The mixed solution was dispersed in 1000 mfL, sprayed with a spray dryer, and dried to obtain a capsule toner having a coating layer of about 0.3 JJ and 11 thickness.

When 9 g of iron powder (200 to 300 mesh) was added to 1 g of this toner and the friction <y was measured using the known J11 method, it was found to be -10.5 g c/g.

Next, add hydrophobic colloidal silica (product name:
R-972: 0.4% publication of IJ Hon Aerosil)
ij was added externally, and the image was printed by placing it in a copying machine NP-120 (manufactured by Canon). When an unfixed image was taken out and passed through a pressure fixing device consisting of two pressure rollers that can be applied pressure from both ends, it showed almost perfect constant li properties at a linear pressure of 16 kg/cm. Ta. Next, the copying machine was brought into a high humidity environment of 35° C. and 85% RH, and continuous image printing was performed. From the beginning, the image quality was as high as normal humidity, and the image remained unchanged even after printing 30,000 copies.There was no toner adhesion to the surface of the CdS photoreceptor, and it was pressed against the pressure roller of the pressure fixing device. The amount of dirt on the cleaning web was within an acceptable range and was sufficiently cleaned, with no stains on the fixed image. Moreover, no deterioration phenomenon was observed even after leaving it in this state for one month.

Comparative Example 1 A toner was prepared in the same manner as in Example 1, except that the amino-modified silicone oil was not added. The amount of triboelectric charge was -11.21 Lc/g.

Next, 0.4% by weight of hydrophobic colloidal silica was externally added to this toner, and image formation was carried out in the same manner.

At normal humidity, an image similar to Example 1 was obtained, but at 35°C18
In a high humidity environment of 5% RH, the toner coating on the developing sleeve became thinner and the image density also decreased.

After that, when continuous image printing was performed, although the C degree had recovered somewhat, dust was visible on the image during transfer, and when the 3B image printing was completed, black spots were seen on the photoreceptor. Ta.

Further, the recovered toner spilled from the cleaning web, causing stains on the fixed image.

Example 2 The core material was prepared by melt-mixing 70 parts by weight of Caruna wax, 30 parts by weight of aminated polyethylene, and 7 parts by weight of magnetite at 120°C, and suspending the mixture in warm water at 95°C with silica fine particles as a dispersant. 1 station and 1 grain size is 3~2oJLffi
After confirming that the spherical particles are
is.

100 parts of this core particle was dissolved in 400ml of a DMF solution containing 15 parts by weight of styrene-dimethylamine ethyl methacrylate (90:10) copolymer and 1 part by weight of α-olefin-maleic anhydride (t:t) copolymer. When the shell material droplets surround the core particles, amino-modified silicone oil [trade name: KF857 (11'L830 per amine, equivalent to structure (A) in the specification)] : A portion of 10.2 Irr manufactured by Shin-Etsu Chemical Co., Ltd. was added, and further water was added to proceed with curing. After drying and drying, a capsule toner having a coating layer of about 0.37L+11 thickness was obtained.

9 g of iron powder (200 to 300 mesh) was mixed with 1 g of this toner, and the amount of triboelectric charge was measured by a known measuring method and found to be ÷15.8 g c/g.

Next, 0.6% by weight of wet synthetic silica was externally added to this toner, and an image was printed using a copying machine PC-20 (manufactured by Canon Inc.) with the heat fixing device removed.

When the unfixed image was passed through a separately prepared pressure fixing device, it showed almost complete fixation at a linear pressure of 12 kg/cm.

Next, I brought the copying machine into a high humidity environment of 35°C and 85% RH, and i! [I made an image. From the beginning, the image density was as high as that at normal humidity, and the image remained unchanged even after running on 10,000 sheets.

There was no toner adhesion to the surface of the OPC photoreceptor and no image deletion.

Moreover, even if it was left in this state for one month, no deterioration phenomenon was observed.

Comparative Example 2 A toner was prepared in the same manner as in Example 2, except that the amino-modified silicone oil was not added. The amount of triboelectric charge was +11.31 Lc/g.

Next, 0.6% wet synthetic silica was externally added to this toner, and image formation was carried out in the same manner. Even at normal humidity, the image density was somewhat low, but in a high-temperature environment of 35° C. and 85% RH, a decrease in the transfer rate was observed, the image density decreased, and the image quality was affected by many scatterings. Significant recovery was observed in the transfer paper immediately after removal from the moisture-proof packaging, but as the paper absorbed moisture, the transfer worsened. Further, when images were printed continuously, if the surface of the OPC photoreceptor was scratched by paper powder, magnetic powder in the toner, etc., black dot-like fusion of the toner occurred after about 3,000 to 4,000 sheets were printed.

Comparative Example 3 A toner was prepared in the same manner as in Example 2, except that the α-olefin-maleic anhydride copolymer was not useful. The amount of triboelectric charge was ÷14.9 pc/g.

Next, when 0.6% wet synthetic silica was externally added to this toner and an image was produced in the same manner, an image with the same cutout as in Example 2 was obtained, but it was left as it was. However, gradually a shadow appeared on the image of III. Further, when images were continuously printed in a high humidity environment of 35° C. and 185% RH, the images on the drum were disturbed and appeared to flow.

Example 3 A toner was prepared in the same manner as in Example 2, except that the amount of amino-modified silicone was reduced to 0.05 parts by weight.

The amount of triboelectric charge was +14.5 lc/g.

The same results as in Example 2 were obtained.

Table 1 Image density tree 1 Toner fused onto photoconductor 2 Image blur χ Example 4 3 parts by weight of carbon black, 10 parts by weight of hexamethylene diink, 10 parts by weight of TIF, 20 parts by weight of dibutyl phthalate, 10 parts by weight of cyclized rubber part, polyethylene wax 40
Parts by weight, 70 parts by weight of magnetite, and 50 parts by weight of toluene were mixed and dispersed in a P4 Pall mill, and the resulting paste-like core material was put into 5% polyvinyl alcohol IfL, and mixed with a high-speed stirrer for 5 to 50 parts by weight. 20 layers of suspended grains were obtained.

11 weight of amino-modified silicone oil [trade name: KF857] was stirred and added to DMF lOmJlj at room temperature, the temperature was raised to 80°C, and 150ml of a 10% aqueous solution of hexamethylene diamine was added, and the reaction was continued for 2 hours. . After cooling, 10 times the amount of water was added, the mixture was allowed to stand, the supernatant liquid was discarded, water was added, the mixture was washed, and the process of filtration was repeated three times.

The particles obtained after drying were smooth, and were similar to those of Example 2.
Similarly, the amount of frictional charge is I! lII added +7
．． It was 91 Lc/g.

Next, 0.6% by weight of wet synthetic silica was externally added to this toner, and an image was produced in the same manner as in Example 2, resulting in a clear and fog-free image. This toner weighs 8 kg
It was fixed with a linear pressure of /cm and exhibited good abrasion resistance and bending resistance.

Even when this toner was brought to a high humidity environment of 35° C. and 185% R1, it maintained a high image density. Even after running for 10,000 sheets, no background fogging or the like of the image occurred.

Comparative Example 4 Example 4 except that it does not contain amino-modified silicone oil
I did the same thing. b1) Some of the 2 particles collected were seen to be agglomerated. Friction a;) Electric φ is +3.81L
c/g. Immediately after drying, this toner produced an image with a high density, but when images were printed continuously at room temperature and humidity, the image density rapidly decreased, and in a high humidity environment of 35°C and 85% RH, the image density was completely reduced. Didn't get a picture.

Example 5 10 parts by weight of Carna wax, 40 parts by weight of polybutene oil, 2 parts by weight of lecithin, and 5 parts by weight of phthalocyanine blue were mixed and dispersed in a Pall mill. This dispersed ink was coated with liquid epoxy, and 10 parts by weight of liquid epoxy (trade name: Epicor) 815 (epoxy weight: 183-193) manufactured by Nigel Chemical Co., Ltd. and a curing agent consisting of an adduct of an aliphatic amine and an epoxy compound [trade name: Ebikyu 7T manufactured by Niji Koru Chemical] 2 parts by weight and epoxy modified silicone oil [Product name: 5F
8411 (epoxy equivalent: 3,000): 12 parts by weight of Toshi Silicone Co., Ltd. were dissolved in 20 parts by weight of dibutyl phthalate, and the mixture was moderately dispersed in an attritor while cooling to around 0°C. Next, 2% of gum arabic
Aqueous solution 19. Add and disperse the mixture while keeping it cool at 20°C or less, mix and stir with a high-speed dispersion machine, and mix for 5~
η particles were obtained with a suspension of 20 lm. Next, the liquid temperature was raised to 80°C, and the reaction was carried out at this temperature for 8 hours. The obtained slurry was washed several times with water and then dried to obtain a blue toner.

Apply this blue toner to the Canon Mini Copia PC-22.
When I replaced the contents with the contents of the n-color color kit and printed the image, I obtained a clear i-color image.When I passed the 6 unfixed images through a 15 kg/cm pressure fixing device, they were sufficiently fixed. showed his sexuality. When the triboelectric charge amount of this toner was measured in the same manner as in Example 2, it was +35.51 Lc/g.

When this toner was brought into a high-humidity environment of 35° C. and 85% RH for image printing, a slight decrease in density was observed.

When the amount of epoxy-modified silicone oil was increased to 5 parts by weight, the decrease in concentration was suppressed.

Table 2 [Effects of the Invention] As described above, the capsule toner of the present invention has an outer shell containing a polymer or copolymer capable of reacting with the reactively modified polyorcasiloxane and a reactive functional group. Contains a reaction product with reactively modified polyorganosiloxane, and since the polyorganosiloxane exists chemically bonded to the toner surface layer, it has the moisture resistance and anti-fusing properties of polyorganosiloxane, and has a high It exhibits excellent developability and transferability even in a humid environment, and prevents the toner from adhering to members that come into contact with the toner, such as the photoreceptor, developing sleeve, carrier, and pressure roller.

Although the example of pressure fixing was described in the non-experimental example, the toner of the present invention can be suitably used not only for pressure fixing but also for heat fixing, and can be used for fixing at an extremely low temperature and with low energy compared to conventional toners. becomes possible. In this case as well, the presence of polyorganosiloxane can prevent toner offset, especially in contact type systems such as hot roll fixing.
Shows good resistance.

Claims (1)

[Claims] In a capsule toner composed of a core material and an outer shell covering the core material, the outer shell contains a polymer or copolymer capable of reacting with a reactively modified polyorganosiloxane, and a reactively modified polyorganosiloxane having a reactive functional group. A capsule toner characterized by containing a reaction product with a polyorganosiloxane.