JP2662420B2 - Elastic rotating body having addition reaction type silicone rubber composition and fixing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an alkylsilane compound, dimethylsilicone oil or a mixture thereof, and a silane compound containing an unsaturated group reactive to an addition-reactive silicone. An elastic rotating body having an elastic body having a surface layer formed of a dimethyl silicone rubber composition produced from an addition-reaction dimethyl silicone composition containing a synthetic silicic acid surface-treated with A fixing device having the fixing device. In particular, the present invention relates to an elastic rotating body used as a transport roller for transporting a sheet-like transfer material or a recording material or a fixing roller for fixing in an electrophotographic copying apparatus, a printer, and various other image forming apparatuses. It is suitable for the elastic covering material.

[Conventional technology]

2. Description of the Related Art In an image forming apparatus such as an electronic copying apparatus, a transport roller that transports a sheet-like transfer material such as plain paper or a recording material along a predetermined path is generally required to have transportability, release properties, and durability.

In particular, a fixing roller and a heat roller which must apply heat to the unfixed toner image on the transfer paper under a pressurized condition and transport the transfer paper to a predetermined path while preventing the semi-fused or molten toner from offsetting. In a fixing device equipped with a pressure roller, transportability under severer conditions, release properties, wear resistance,
Fixing properties and durability are required.

Conventionally, this type of fixing device has at least a fixing roller and a pressing roller that is driven to rotate in contact with the fixing roller.
The fixing roller is formed of a material layer having good releasability, such as a fluorine-based resin such as polytetrafluoroethylene, tetrafluoroethylene-fluoroalkoxyethylene copolymer, or silicone rubber, on a hollow core metal such as aluminum or iron. Is coated. In addition, a heater such as a halogen lamp is provided in the fixing roller as necessary, and the surface of the fixing roller is heated to a temperature suitable for fixing. In many cases, the sensor is controlled using a sensor so that the surface temperature of the fixing roller becomes a set temperature. Further, the outer peripheral surface of the fixing roller may be provided with a cleaner for removing offset toner and paper dust, and a separation claw for preventing the image carrier from being wound around the fixing roller.

On the other hand, in the pressure roller, an elastic layer having releasability such as silicone rubber is coated on a core metal such as iron or stainless steel. The pressure roller is pressed against the fixing roller by a spring or the like.

Thus, the image bearing material having the unfixed toner image is nipped and conveyed under pressure by the fixing roller and the pressure roller, so that the unfixed toner image is pressure-fixed.

[Problems to be solved by the invention]

However, when a conventional dimethyl silicone rubber is used for the core metal outer peripheral surface coating layer of the fixing roller, the silicone rubber-coated fixing roller is capable of fixing an unfixed toner image to an image supporting material such as plain paper, fixing image quality, That is, there is a problem that although the image quality is excellent, the releasability and the durability are inferior to those of the fluororesin-coated fixing roller.

In an image forming apparatus such as an electronic copying machine, from the viewpoint of emphasizing image quality, a releasability and durability are inferior to those of a fluorine-based resin-coated fixing roller, but a silicone rubber-coated fixing roller having excellent image quality is employed. Various researches and developments have been made to improve the releasability and durability of silicone rubber materials as much as possible. However, to date, no method has been obtained that can significantly improve the releasability and durability using dimethyl silicone rubber. For example, as a technique for improving the durability, it is known that a synthetic silicic acid such as hydrated synthetic silicic acid or anhydrous synthetic silicic acid is blended and contained as a reinforcing agent. However, in the case of hydrous synthetic silicic acid, the reinforcing effect is not exhibited unless the addition amount is as large as 20 to 50 parts by weight. To make matters worse, the releasability is greatly reduced. In the case of synthetic silicic anhydride,
Although a certain amount of reinforcing effect can be obtained with a small amount (for example, 10 to 20 parts by weight) as compared with hydrous synthetic silicic acid, the releasability is still greatly reduced. Therefore, in either case, the durability could not be significantly improved without lowering the releasability.

[Means for solving the problem]

In the electrophotographic copying machine, the printer, and various other image forming apparatuses, the present inventor conveys a sheet-like transfer material such as plain paper or a recording material and fixes an unfixed image-formed image to form a permanent image. As a result of extensive research on a silicone rubber composition having both releasability and durability as a coating of an elastic rotating body for the purpose of performing, an alkyl silane compound, dimethyl silicone oil or a mixture thereof, and an addition reaction type Addition-reaction type dimethyl silicone rubber contains a specific amount of synthetic silicic acid whose surface has been treated (modified) with a silane compound containing a functional group reactive with silicone, so that it has reinforcement and mold release properties. Roller capable of obtaining a silicone rubber in good balance with the silicone rubber, and further having a coating layer formed from the silicone rubber composition And it found that the durability is significantly improved is the present invention has been completed.

[Object of the invention]

An object of the present invention is to provide an elastic rotating body having excellent mechanical strength and good releasability.

An object of the present invention is to provide an elastic rotating body having excellent durability.

An object of the present invention is to provide a fixing device having excellent durability.

SUMMARY OF THE INVENTION The present invention provides a diorganopolysiloxane component containing a vinyl group (I); a siloxane component containing an active hydrogen (II); a catalytic amount of a platinum-based catalyst component (III); and a BET specific surface area of 40 to 500 m ² / (i) 1 to 30 parts by weight of a treating agent comprising alkylsilane, hexamethyldisilazane, dimethylsilicone oil or a mixture thereof, and (ii) vinyltriethoxysilane, dimethyl Vinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane,
Reaction with an addition-reactive silicone selected from the group consisting of methylvinyldiethoxysilane, vinyltrichlorosilane, dimethylvinylchlorosilane, methylvinyldichlorosilane, γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropylmethyldimethoxysilane Release and reinforcing component (I) comprising a surface-modified synthetic silicate fine powder whose surface has been treated with 1 to 30 parts by weight of a silane compound containing an unsaturated group having a hydrophilic property (I
V), at least 5 to 20 parts by weight of component (IV) based on 100 parts by weight of components (I), (II) and (III), and components (I) and (IV) The molar ratio of the silicon-bonded hydrogen atom contained in the component (II) to the total amount of unsaturated groups contained in the compound is 0.6 to 1.5.
A release surface layer formed from a dimethylsilicone rubber composition formed by heat-treating an addition-reaction dimethylsilicone composition containing the components (I), (II) and (IV) so that The present invention relates to an elastic rotating body having an elastic body having the same.

Further, the present invention provides a fixing device which heat-presses and fixes an unfixed toner image formed on an image bearing material by nipping and transporting the image bearing material between at least a pair of rollers. Is a resilient material having releasability from the toner, wherein the resilient material is a vinyl group-containing diorganopolysiloxane component (I); an active hydrogen-containing siloxane component (II); a catalytic amount of a platinum-based catalyst component (III); And (1) 1 to 30 parts by weight of a treating agent comprising alkylsilane, hexamethyldisilazane, dimethylsilicone oil or a mixture thereof per 100 parts by weight of synthetic silica fine powder having a BET specific surface area of 40 to 500 m ² / g; (Ii) vinyltriethoxysilane, dimethylvinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane,
Reaction with an addition-reactive silicone selected from the group consisting of methylvinyldiethoxysilane, vinyltrichlorosilane, dimethylvinylchlorosilane, methylvinyldichlorosilane, γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropylmethyldimethoxysilane Release and reinforcing component (I) comprising a surface-modified synthetic silicate fine powder whose surface has been treated with 1 to 30 parts by weight of a silane compound containing an unsaturated group having a hydrophilic property (I
V), at least 5 to 20 parts by weight of component (IV) based on 100 parts by weight of components (I), (II) and (III), and components (I) and (IV) The molar ratio of the silicon-bonded hydrogen atom contained in the component (II) to the total amount of unsaturated groups contained in the compound is 0.6 to 1.5.
A release surface layer formed from a dimethylsilicone rubber composition formed by heat-treating an addition-reaction dimethylsilicone composition containing the components (I), (II) and (IV) so that The present invention relates to a fixing device characterized by being formed of an elastic body having the fixing device.

[Specific description of the invention]

The addition reaction type dimethyl silicone composition used in the present invention contains the following components.

Component (I): General formula A dimethylpolysiloxane endblocked by a vinyl group represented by the general formula And a vinyl group-containing dimethylpolysiloxane comprising a terminal methyl group-blocked side-chain vinyl group-containing dimethylpolysiloxane or a mixture thereof (wherein l, m and n in the formula are positive integers).

Component (II): General formula A hydrogen atom bonded to a silicon atom represented by Is at least one methylhydrogenpolysiloxane per molecule (p is 0 or a positive integer, q is a positive integer).

(III) a platinum-based catalyst (platinum or a platinum compound).

(IV) Synthetic silica fine powder 10 having a BET specific surface area of 40 to 500 m ² / g
(I) 1 to 30 parts by weight of alkylsilane per 0 parts by weight,
Surface treatment with both a treating agent composed of hexamethyldisilazane, dimethylsilicone oil or a mixture thereof, and (ii) a silane compound having an unsaturated group reactive with 1 to 30 parts by weight of an addition-reactive silicone. Treated silica fine powder with surface modification.

The addition reaction type dimethyl silicone rubber composition used in the present invention is a curable composition formed from a homogeneous mixture of the above silicone composition, and the components (I), (II) and (III) constituting the composition. Is a liquid addition reaction type dimethyl silicone composition. Ingredient (I)
Vinyl group bonded to silicon atom in And hydrogen atom bonded to silicon atom in component (II) Is heated in the presence of a platinum-based catalyst to initiate an addition reaction, whereby the silicone composition becomes a silicone rubber composition and a rubber-like elastic body.

Synthesis of anhydrous synthetic silicic acid or hydrous synthetic silicic acid with an alkylsilane compound, dimethyl silicone oil or a mixture thereof as a component (IV) constituting the composition used in the present invention and a reactive unsaturated group-containing silane compound. The surface of the silicic acid fine powder is treated, and the unsaturated group on the surface of the treated synthetic silicic acid fine powder reacts with the silicon-bonded hydrogen atom of the component (II) to form a chemical bond. Mechanical strength that would not otherwise be obtained can be obtained by adding a relatively small amount of the component (IV), and furthermore, preventing or increasing the increase in surface energy of the molded product due to the addition of a large amount of filler such as synthetic silicic acid. , Can be suppressed. As the synthetic silicic acid according to the present invention, white ultrafine powdered silicic anhydride (SiO ₂ .nH
₂ O, SiO ₂ 95% or more), hydrous silicic acid (SiO ₂ nH ₂ O, SiO ₂
80-95%) hydrated calcium silicate (x ・ SiO ₂・ CaO ・ yH ₂
O, SiO ₂ 55 ~ 70%), hydrous aluminum silicate (x ・ Si
O ₂ · Al ₂ O ₃ · yH ₂ O, SiO ₂ is 60 to 70%). Fine powder having a primary particle diameter of 7 to 100 μm and a BET specific surface area of 40 to 500 m ² / g is preferably used. Can be

Examples of surface treatment agents include alkyl silanes such as trimethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, and methyltrichlorosilane; Disilazane and dimethyl silicone oil are exemplified.

Further, as a silane compound containing an unsaturated group having reactivity with an addition reaction type silicone, vinyltriethoxysilane, dimethylvinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane, methylvinylethoxysilane, vinyltrichlorosilane,
Dimethylvinylchlorosilane, methylvinyldichlorosilane, γ-methacryloxypropyltrimethoxysilane, and γ-methacryloxypropylmethyldimethoxysilane are exemplified as described above. The treating agent is used for surface treatment of synthetic silicic acid by a known treating method. In order to improve the releasability and the dispersibility by improving the wettability with the component (I) and the component (II), the alkyl silane, hexamethyldisilazane, dimethyl silicone oil or a mixture thereof exemplified above is used. It is preferable to treat with an amount of 1 to 30 parts by weight (more preferably 3 to 25 parts by weight) based on 100 parts by weight of the synthetic silica fine powder. Further, from the viewpoint of the specific surface area, the synthetic silica fine powder is preferably coated at a ratio of 30 to 90%, more preferably 40 to 80% of the specific surface area.

Further, in order to reinforce the silicone rubber composition, it is coated with an unsaturated group-containing silane in an amount of 1 to 30 parts by weight (more preferably 5 to 25 parts by weight) based on 100 parts by weight of the synthetic silica fine powder. Is preferred. Further, from the viewpoint of the specific surface area, the synthetic silica fine powder is preferably coated at a ratio of 10 to 60%, preferably 20 to 60% (more preferably 30 to 50%) of the specific surface area. The amount of this surface-treated synthetic silicic acid was 100% of the components (I), (II) and (III).
It is preferable to use it in the range of 5 to 30 parts by weight (particularly 5 to 20 parts by weight) with respect to parts by weight in terms of both releasing property and reinforcing property.

The rubber composition (cured product or molded product) produced from the silicone composition of the present invention composed of the components (I), (II), (III) and (IV) has a low content in the composition. The molar ratio of the silicon-bonded hydrogen atom to the saturated group is in the range of 0.6 to 1.5, preferably the molar ratio is in the range of 0.8 to 1.2, and particularly when the molar ratio is 1.0, the mechanical strength, hardness, and rebound resilience Is good, and the releasability is also good. Although the reason for this is not always clear, the absence of unreacted components in the cured silicone rubber improves the mechanical strength and viscoelastic properties of the cured product, and prevents an increase in surface energy of the cured product. It is considered to suppress or suppress the phenomenon of adsorption of the toner to the surface of the cured product, which is considered to be caused by the presence of unreacted components. However, such description does not limit the present invention in any way.

Therefore, the amounts of the components (I), (II) and (IV) are adjusted so that the total amount of unsaturated groups in the components (I) and (IV) is substantially equal to the amount of silicon-bonded hydrogen atoms in the component (II). It is necessary to prepare

In addition, a colorant, a heat resistance improver, a compression set improving agent, etc. may be added to the addition reaction type silicone composition and the silicone rubber composition of the present invention as long as the object of the present invention is not impaired. .

The composition of the present invention can be prepared by simply mixing the components together.
Solution A consisting of (III) and (IV) and components (II) and (I
V) or separately prepared into solution B, or
The composition is separately prepared into a liquid A composed of the components (I), (III), and (IV) and a liquid B composed of the components (I), (II), and (IV). It is most convenient to mix the two components, Solution A and Solution B, at a predetermined mixing ratio during the conversion.
At this time, the unsaturated group-containing component and The components and the platinum-based catalyst component must not be included in the same package.

The addition-reaction-type dimethyl silicone rubber composition used in the present invention can be used to form an unfixed image of a sheet-like transfer material such as plain paper or a recording material from conveyance in an electrophotographic copying machine, a printer, and various other image forming apparatuses. It is suitably used as an elastic covering material of an elastic rotating body for fixing an image to form a permanent image.

Hereinafter, the elastic rotating body and the fixing device of the present invention will be described.

FIG. 4 is a cross-sectional side view showing an extremely schematic configuration of an example of the apparatus. Reference numerals 1 and 2 denote a heat roller (hereinafter, referred to as a fixing roller) and a pressure roller, which are appropriately pressed and brought into contact with each other and supported vertically in parallel, and are driven to rotate in the direction of the arrow.

The fixing roller 1 is a hollow roller 11 made of metal such as aluminum.
An elastic coating layer 12 obtained by coating the outer peripheral surface of the core metal with the addition reaction type dimethyl silicone rubber composition of the present invention, and a heater 13 such as a halogen heater rod is inserted and disposed inside the core metal. Heated by the heat generated by the heater. Then, the power supply to the heater 13 is controlled on / off or controlled by a power supply amount by an automatic temperature control means (not shown), so that the temperature of the outer peripheral surface of the fixing roller is constantly maintained at a predetermined constant temperature. The pressure roller 2 is formed by using a metal roller made of a metal such as iron or aluminum as a core metal 21 and covering the outer peripheral surface thereof with a relatively thick elastic material layer 22 such as rubber. The addition reaction type dimethyl silicone rubber composition of the present invention may be used for the elastic material layer. Reference numeral 3 denotes an apparatus for applying a release aid such as dimethyl silicone oil to the outer peripheral surface of the fixing roller 1. In this embodiment, a long web member 31 previously impregnated with a release aid having a considerably high viscosity is used. The roll-wound material is mounted and held on a pay-out shaft 32, and the free end of the roll-wound web member is locked to a take-up shaft 33, and a web member portion between the pay-out shaft and the take-up shaft is pressed by a pressing roller 34.
And presses the roll-wound web member on the pay-out shaft side little by little to the take-up shaft side to coat the impregnating and releasing aid of the web member on the outer peripheral surface of the fixing roller 1. It is of a configuration. This web member also serves as a cleaning member for the outer surface of the fixing roller.

When the fixing roller 1 and the pressure roller 2 are driven to rotate, the nip portions 4 of the two rollers are not fixed by an image forming mechanism (not shown) such as an electrophotographic system or an electrostatic recording system. When an image supporting material (transfer material, electro-fax paper, electrostatic recording paper, etc.) 5 on which the toner image T is formed and carried is introduced and passed with the toner image carrying surface side facing the fixing roller 1, the toner image T Are sequentially subjected to a heat-pressure fixing process as a permanent fixed image on the surface of the image supporting material 5 by the heat of the fixing roller 1 and the mutual pressing force of the fixing roller 1 and the pressing roller 2.

Reference numeral 6 denotes a separating claw member provided to surely separate the image supporting member 5 from the surface of the fixing roller 1, and 7 denotes a fixing claw member.
A sensor W for detecting the roller outer peripheral temperature for controlling the temperature of the fixing roller 1 and a pressing roller 2 indicates a width dimension (nip width) of a contact portion between the fixing roller 1 and the pressing roller 2.

The thickness of the releasable material 12 covering the outer periphery of the core 11 in the fixing roller 1 is generally quite thin so that the heater heat can be quickly supplied to the outer surface of the material layer, that is, the outer peripheral surface of the fixing roller. (For example, about 0.5 mm).

When the addition-reaction-type dimethyl silicone rubber composition of the present invention is used for the coating material layer 12 of the fixing roller 1, the cured product of the composition is an elastic body, so that the surface unevenness of the support material 5 itself and the unevenness on the support material are increased. The outer surface of the elastic body coating layer conforms to the unevenness of the toner image T and deforms well, so that the uneven toner image T is uniformly contacted with each part, so that the overall fixability of the toner image T to the image supporting material 5 surface is improved. In addition, the overall fixed image, that is, the image quality is improved. Therefore, the image collapse, gloss, toner scattering, and the like that occur when the rigid coating layer is used are improved or eliminated.

 The present invention will be described in more detail based on the following examples.

[Experimental Example 1] Component (I): dimethylpolysiloxane having a terminal vinyl group blocked.
And dimethyl-polysiloxane containing side-chain vinyl groups with terminal methyl groups blocked
Total number of vinyl groups consisting of oxane is 8.0 × 10^-Fivemol / g
Nyl group-containing dimethylpolysiloxane 100 parts by weight Component (II): the number of silicon-bonded hydrogen atoms is 2.0 × 10^-3mol / g
7.15 parts by weight of component (III): platinum catalyst ... 0.001 part by weight Component (IV): containing dimethyl silicone oil and vinyl group
Surface modification of vinyl group containing silane compound
Hydrous synthetic silica ... 10 parts by weight Component (V): Bengala ... 1 part by weight Component (IV) was prepared as follows. Average particle size is 8.6μ
m, specific surface area is 114m^Two/ g dimethyl silicon
Hydrated synthetic silica whose surface has been treated with oil (about 9% by weight)
Acid Fine Powder (Nippon Silica Hydrophobic Silica NIPSIL SS30
P) 100 parts by weight are introduced into the stirrer, while forcibly stirring.
12 parts by weight of vinyltriethoxysilane was gradually dropped
After that, remove from the stirrer and air dry at 100 ° C for 1 hour.
Reactive vinyl group-containing surface-modified hydrous synthetic silica was obtained. This
The amount of vinyl groups in the powder is about 3.8 × 10²⁰Individually
there were.

Components (I), (II), (III), (IV), and (V) are components that constitute the composition according to the present invention, and the total amount of vinyl groups in the composition and the silicon-bonded hydrogen atoms are substantially the same. It was prepared to be equimolar. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) 45.35 parts by weight Component (III) 0.001 part by weight Component (IV) 4.23 parts by weight Component (V) 0.43 parts by weight Liquid B: Component (I) 39.29 parts by weight Part Component (II): 6.05 parts by weight Component (IV): 4.23 parts by weight Component (V): 0.43 parts by weight Both the A liquid and the B liquid were uniformly mixed and prepared. The obtained liquid A and liquid B were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body formed from the silicone rubber composition. Was.
The rubber-like elastic body was further post-cured at 200 ° C. for 4 hours.

[Experimental Example 2] Component (I): Including dimethylpolysiloxane endblocked with a terminal vinyl group and side chain vinyl group endblocked with a methyl group.
The total number of vinyl groups composed of dimethylpolysiloxane is 8.
0x10^-Fivemol / g vinyl group-containing dimethylpolysiloxane 100 parts by weight Component (II): The number of silicon-bonded hydrogen atoms is 2.0 × 10^-3mol / g
7.15 parts by weight Component (III): Platinum catalyst ... 0.001 parts by weight Component (IV): Hydrophobized anhydrous synthetic silicic acid contains vinyl groups
Surface-modified synthetic resins containing vinyl groups modified with silane compounds
Ionic acid 10 parts by weight Component (V): Bengala 1 part by weight Component (IV) was prepared as follows. Specific surface area is 200m^Two/
g, about 6% by weight of dimethyldichlorosila having a bulk specific gravity of 50 g /
Hydrophobic Synthetic Silica Fine Powder from Degussa
Body aloesil 100 parts by weight of R812 was introduced into the stirrer,
With forced stirring, add 12 parts by weight of vinyltriethoxysilane.
Drop it slowly, and after dropping, take it out of the stirrer,
Air-dried at 100 ° C for 1 hour to modify the target vinyl group-containing surface
An anhydrous synthetic silicic acid was obtained. The amount of vinyl groups in this powder is about 3.8
× 10²⁰Pieces / (1 g of powder).

Components (I), (II), (III), (IV), and (V) are components that constitute the composition according to the present invention, and the total amount of vinyl groups in the composition and the silicon-bonded hydrogen atoms are substantially the same. It was prepared to be equimolar. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) 45.35 parts by weight Component (III) 0.001 part by weight Component (IV) 4.23 parts by weight Component (V) 0.43 parts by weight Liquid B: Component (I) 39.29 parts by weight Part Component (II): 6.05 parts by weight Component (IV): 4.23 parts by weight Component (V): 0.43 parts by weight Both the A liquid and the B liquid were uniformly mixed and prepared. The obtained liquid A and liquid B were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body. Further, post-curing was performed at 200 ° C. for 4 hours.

[Experimental Example 3] The composition according to the present invention was obtained from the components (I), (II) and (III) of the experimental example 1 and the component (IV) shown below.

Component (IV): containing methyltrimethoxysilane and vinyl group
Vinyl group-containing surface modified hydrous surface modified with silane
Silicic acid ... 10 parts by weight Component (IV) was prepared as follows. Average particle size 2 μm,
Specific surface area 170m^Two/ g hydrous synthetic silica fine powder (Nippon Silica)
NIPSIL N300A) 100 parts by weight introduced into the stirrer and forced
While stirring, gradually add 3 parts by weight of methyltrimethoxysilane.
After dropping, add vinyl triethoxysila
In the same manner, 12 parts by weight of the solvent were gradually dropped. After dropping,
Remove the powder from the stirrer and air dry at 100 ° C for 1 hour
As a result, the desired vinyl-containing surface-modified hydrous synthetic silica was obtained.
The amount of vinyl groups in this powder is about 3.8 × 10²⁰Individual
Was.

Components (I), (II), (III), (IV), and (V) are components that constitute the composition according to the present invention, and the total amount of vinyl groups in the composition and the silicon-bonded hydrogen atom are different from each other. It was prepared to be almost equimolar. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) 45.35 parts by weight Component (III) 0.001 part by weight Component (IV) 4.23 parts by weight Component (V) 0.43 parts by weight Liquid B: Component (I) 39.29 parts by weight Part Component (II): 6.05 parts by weight Component (IV): 4.23 parts by weight Component (V): 0.43 parts by weight Both the A liquid and the B liquid were uniformly mixed and prepared. The liquids A and B thus obtained were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body formed of a silicone rubber composition. . The rubber-like elastic body was further post-cured at 200 ° C. for 4 hours.

[Comparative Experimental Example 1] 100 parts by weight of dimethylpolysiloxane having a vinyl group, 5 parts by weight of synthetic anhydrous silicic acid, 20 parts by weight of quartz powder, 1
A having a viscosity of 800 poise and consisting of parts by weight and a platinum-based catalyst
Liquid B having a viscosity of 600 poise consisting of 100 parts by weight of a mixture of liquid and vinyl group-containing diorganopolysiloxane and active hydrogen group-containing siloxane, 5 parts by weight of anhydrous synthetic silicic acid, 20 parts by weight of quartz powder, and 1 part by weight of bengara is weighed. After mixing at a ratio of 100 to 100 and defoaming, the mixture was heated at 150 ° C. for 10 minutes by a hot press to obtain a rubber-like elastic body. The rubber-like elastic body is further 200
Post-curing was performed at 4 ° C. for 4 hours.

[Comparative Experimental Example 2] A rubber-like elastic body was obtained in the same manner as in Comparative Experimental Example 1 except that the content of the synthetic silicic anhydride was 30% by weight.

[Comparative Experimental Example 3] Component (I) containing a vinyl group having a total number of 8.0 × 10 ^-5 mol / g of vinyl groups composed of a dimethylpolysiloxane having a terminal vinyl group and a dimethylpolysiloxane having a side chain vinyl group having a terminal methyl group. Dimethylpolysiloxane: 100 parts by weight Component (II): the number of silicon-bonded hydrogen atoms is 2.0 × 10 ⁻³ 3 mol /
g of methylhydrogenpolysiloxane 4 parts by weight Component (III): platinum catalyst 0.001 part by weight Component (V): Bengala 1 part by weight The above components (I), (II), (III) and (V) Is a component constituting the silicone composition, and was prepared so that the total amount of vinyl groups in the composition was equimolar. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) ... 52 parts by weight Component (III) ... 0.001 parts by weight Component (V) ... 0.5 parts by weight Liquid B: Component (I) ... 48 parts by weight Component (II) ... 4 parts by weight Component (V) ... 0.5 part by weight Both solution A and solution B were prepared by uniformly mixing. The obtained liquid A and liquid B were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body. The rubber-like elastic body was further post-cured at 200 ° C. for 4 hours.

[Comparative Experimental Example 4] Component (I): dimethylpolysiloxane having a terminal vinyl group blocked.
And dimethyl-polysiloxane containing side-chain vinyl groups with terminal methyl groups blocked
Total number of vinyl groups consisting of oxane is 8.0 × 10^-Five5mol / g
Vinyl group-containing dimethylpolysiloxane 100 parts by weight Component (II): the number of silicon-bonded hydrogen atoms is 2.0 × 10^-3mol / g
7.15 parts by weight Component (III): Platinum catalyst ... 0.001 parts by weight Component (IV): Surface modified with vinyl group-containing silane compound
Vinyl group-containing surface-modified synthetic silicic acid: 10 parts by weight Component (V): Bengala: 1 part by weight Component (IV) was prepared as follows. Average particle size is 2μm
And the specific surface area is 170m^Two/ g of hydrous synthetic silicic acid (Nippon Si
Rica NIPSIL N300A) 100 parts by weight introduced into the stirrer
And 12 g of vinyltriethoxysilane with forced stirring
Portion is gradually dropped, and after the dropping is completed, the powder is removed from the stirring device.
And air-dried at 100 ° C for 1 hour to contain the desired vinyl group
A surface-modified hydrous synthetic silica was obtained. Vinyl content of this powder
Is about 3.8 × 10 per 1g of powder²⁰Pcs / g.

Components (I), (II), (III), (IV), and (V) are components constituting a silicone composition, and the total amount of vinyl groups and silicon-bonded hydrogen in the composition are equimolar. Was prepared as follows. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) 45.35 parts by weight Component (III) 0.001 part by weight Component (IV) 4.23 parts by weight Component (V) 0.43 parts by weight Liquid B: Component (I) 39.29 parts by weight Part: Component (II): 6.05 parts by weight Component (IV): 4.23 parts by weight Component (V): 0.43 parts by weight Both liquid A and liquid B were uniformly mixed and prepared. The liquids A and B thus obtained were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body. The rubber-like elastic body was further post-cured at 200 ° C. for 4 hours.

[Comparative Experimental Example 5] Component (I): dimethylpolysiloxane having a terminal vinyl group blocked.
And polysiloxane containing vinyl group with side chain blocked by methyl group
8.0 × 10^-Fivemol / g of vinyl group
Dimethyl polysiloxane ... 100 parts by weight Component (II): The number of silicon-bonded hydrogen atoms is 2.0 × 10^-3mol / g
4 parts by weight of methylhydrogenpolysiloxane Component (III): Platinum catalyst 0.001 part by weight Component (IV): Modified surface with methyltrimethoxysilane
Hydrous synthetic silicic acid ... 10 parts by weight Component (V): Benkara ... 1 part by weight Component (IV) was prepared as follows. Average particle size is 2μm
And the specific surface area is 170m^Two/ g of hydrous synthetic silicic acid (Nippon Si
Rica NIPSIL N300A) 100 parts by weight introduced into the stirrer
And 3 g of methyltriethoxysilane with forced stirring
Part was gradually added dropwise. After dropping, the powder is removed from the stirring device.
Remove and air-dry at 100 ° C for 1 hour to achieve the desired surface modification
A hydrous synthetic silicic acid was obtained.

Components (I), (II), (III), (IV), and (V) are components constituting a silicone composition, and the amount of vinyl groups and silicon-bonded hydrogen atoms in the composition are equimolar. Was prepared as follows. Each component was packaged in a two component format as shown below.

Liquid A: Component (I) ... 52 parts by weight Component (III) ... 0.001 parts by weight Component (IV) ... 5 parts by weight Component (V) ... 0.5 parts by weight Liquid B: Component (I) ... 48 parts by weight Part Component (II) ... 4 parts by weight Component (IV) ... 5 parts by weight Component (V) ... 0.5 parts by weight Both liquid A and liquid B were uniformly mixed and prepared. The obtained liquid A and liquid B were mixed at a weight ratio of 100: 100, and after defoaming, heated at 150 ° C. for 10 minutes with a hot press to obtain a rubber-like elastic body. The rubber-like elastic body was further post-cured at 200 ° C. for 4 hours.

Table 1 below shows the physical properties of the rubber-like elastic bodies and the toner releasability in Experimental Examples 1 to 3 and Comparative Experimental Examples 1 to 5.

(*) Toner releasability: 50 circular toner images with a diameter of 2 mm and a thickness of 50 μm are formed on a rubber test piece (20 × 60 × 15 mm).
The toner image is heated and melted at 180 ° C. (ambient temperature) for 30 minutes, and then cooled to room temperature. Adhesive tape is applied on the fused and solidified toner image, and a constant load (Kg weight) roller is
Peel off the tape after 10 reciprocations. At this time, the toner peeling state is classified into five stages, the number of each stage is obtained and scored,
The sum of the scores at each stage divided by the total score (50 × 4 = 200 points) was defined as the toner releasability (%). The classification of the toner peeled state was performed as follows.

A: Completely peeled state (4 points) B: Intermediate state between A and C (3 points) C: State in which half of the total area is peeled off (2 points) D: Intermediate state between C and E ( 1 point) E: Completely remaining state (0 point) The sample used in the test was aged at 200 ° C. for 4 hours.

[Experimental Example 4] The amount of the vinyl group-containing surface-modified hydrous synthetic silicic acid whose surface was modified with dimethyl silicone oil and vinyl group-containing silane of Experimental Example 1 was adjusted to 100 parts by weight of the vinyl group-containing dimethylpolysiloxane of the component (I). 10 parts by weight per part
The amount of the methylhydrodienepolysiloxane of I) was varied. At this time, the total amount (total mole number) of the silicon-bonded vinyl group of the component (I), the vinyl group of the vinyl group-containing surface-modified hydrous synthetic silicate whose surface was modified with dimethyl silicone oil and vinyl group-containing silane, and the component ( II) Silicon-bonded hydrogen atom of methylhydrogenpolysiloxane Molar ratio with (Vi represents a vinyl group) was prepared and cured by heating at 150 ° C. for 10 minutes in a hot press to obtain a rubber-like elastic body. The rubber-like elastic body was subjected to a post cure at 200 ° C. for 4 hours. The results of the hardness, rebound resilience and toner releasability of the rubber-like elastic body are shown in FIG. When the vinyl group and the silicon-bonded hydrogen atom in the composition were substantially equimolar, the hardness and the rebound resilience exhibited the maximum values, and the toner releasability exhibited the maximum values.

Example 1 A fixing roller for a heat and pressure fixing device having the addition reaction type dimethyl silicone rubber composition of the present invention as an elastic material layer was manufactured as follows.

First, the surface of an aluminum core having an outer diameter of 58.3 mm (wall thickness 6.5 mm, reverse crown amount 150 μm) at the center is sandblasted, degreased and dried, and then a siloxane-based primer is applied to the surface, and the surface is heated at 130 ° C. Air-dried for 15 minutes.
Next, the core was placed in a cylindrical mold that had been preheated to 150 ° C. in advance. Solution A and Solution B prepared in Experimental Example 1 were uniformly mixed at a weight ratio of 100: 100, and the defoamed mixture was injected into a cylindrical mold and heated at the same temperature (150 ° C).
C) for 5 minutes to cure. The silicone rubber-coated fixing roller removed from the mold after curing had a silicone rubber-coated layer thickness of 0.5 mm.

Using the fixing roller obtained above, a heat fixing type fixing device shown in FIG. 4 was installed, and a continuous paper fixing test was performed under the following conditions.

・ Surface control temperature of fixing roller 1 ... 180-190 ℃ ・ Oil coating device 3 ... Web impregnated with dimethyl silicone oil (product number K96H, manufactured by Shin-Etsu Chemical Co., Ltd.) having a viscosity of 10,000 cs at 25 ℃ Web type equipped with Nomex Paper web (trade name), web feed speed 1m / 10,000 sheets passing (A4 size).

-Paper passing paper: A4 size transfer paper on which an unfixed toner image of the test pattern is formed.

・ Paper passing speed: 70 sheets / min.

The nip width W between the fixing roller 1 and the pressure roller 2 is 9 to 10 mm.

Example 2 A fixing roller was manufactured in the same manner as in Example 1 except that the dimethyl silicone rubber composition of the present invention prepared in Experimental Example 2 was used. Using the fixing roller thus obtained, the continuous paper fixing test shown in Example 1 was performed.

Comparative Example 1 A fixing roller was manufactured in the same manner as in Example 1 except that the dimethyl silicone rubber composition prepared in Comparative Experimental Example 1 was used. Using the fixing roller thus obtained, the continuous paper fixing test shown in Example 1 was performed.

Comparative Example 2 A fixing roller was manufactured in the same manner as in Example 1 except that the dimethyl silicone rubber composition prepared in Comparative Experimental Example 2 was used. Using the fixing roller thus obtained, the continuous paper fixing test shown in Example 1 was performed.

Table 2 below shows the results of the continuous paper fixing test of Example 1, Example 2, Comparative Example 1, and Comparative Example 2.

[Effect of the Invention] When the silicone rubber composition of the present invention is used as a coating material for a heat fixing roller, it is excellent in mechanical strength, and it is possible to obtain sufficient durability since it has good releasability. Make it possible.

The fixing device using the fixing roller having the coating material of the dimethyl silicone rubber composition of the present invention solves problems such as paper curl, paper wrinkle, paper jam, toner offset, and toner adhesion in conveyance and fixing. Excellent releasability and fixing power as well as excellent durability.

In the fixing roller, both the fixing roller and the pressure roller may use the silicone rubber composition of the present invention as a coating material, or may be either the fixing roller or the pressure roller.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the -Si / V molar ratio and hardness in Example 4, and FIG. 2 is a graph showing the relationship between the -Si / V molar ratio and rebound resilience. FIG. 3 is a graph showing the relationship between the molar ratio of -Si / V and the toner releasability.
FIG. 1 shows a schematic configuration of an example of a heat roller type toner image fixing device. DESCRIPTION OF SYMBOLS 1 ... Fixing roller, 2 ... Heating roller, 3 ... Web type oil applicator, 7 ... Temperature sensor, 13 ... Heater, 5 ... Image support material, T ... Unfixed toner image.

Claims (2)

(57) [Claims] 1. A diorganopolysiloxane component containing a vinyl group (I); a siloxane component containing an active hydrogen (II); a catalytic amount of a platinum-based catalyst component (III); and a synthetic silica having a BET specific surface area of 40 to 500 m ² / g. Per 100 parts by weight of the acid fine powder, 1 to 30 parts by weight of a treating agent comprising (i) an alkylsilane, hexamethyldisilazane, dimethylsilicone oil or a mixture thereof; and (ii) vinyltriethoxysilane, dimethylvinylmethoxysilane, Dimethylvinylethoxysilane, methylvinyldimethoxysilane,
Reaction with an addition-reactive silicone selected from the group consisting of methylvinyldiethoxysilane, vinyltrichlorosilane, dimethylvinylchlorosilane, methylvinyldichlorosilane, γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropylmethyldimethoxysilane Release and reinforcing component (I) comprising a surface-modified synthetic silicate fine powder whose surface has been treated with 1 to 30 parts by weight of a silane compound containing an unsaturated group having a hydrophilic property (I
V) and at least 100 parts by weight of components (I), (II) and (III)
It contains 5 to 20 parts by weight of component (IV) and the molar ratio of silicon-bonded hydrogen atoms of component (II) to the total amount of unsaturated groups of components (I) and (IV) is 0.6 to 1.5. Having a releasable surface layer formed from a dimethylsilicone rubber composition produced by heat-treating an addition-reaction-type dimethylsilicone composition containing the components (I), (II) and (IV) as described above. An elastic rotating body comprising a body. 2. A fixing device for fixing an unfixed toner image formed on an image bearing material by heating and pressing by sandwiching and transporting the image bearing material between at least a pair of rollers, wherein a surface layer of at least one of the rollers is fixed. An elastic body having releasability from the toner, the elastic body comprising: a vinyl group-containing diorganopolysiloxane component (I); an active hydrogen-containing siloxane component (II); a catalytic amount of a platinum-based catalyst component (III); (I) 1 to 30 parts by weight of a treating agent comprising alkylsilane, hexamethyldisilazane, dimethylsilicone oil or a mixture thereof per 100 parts by weight of synthetic silica fine powder having a BET specific surface area of 40 to 500 m ² / g; ii) vinyltriethoxysilane, dimethylvinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane,
Reaction with an addition-reactive silicone selected from the group consisting of methylvinyldiethoxysilane, vinyltrichlorosilane, dimethylvinylchlorosilane, methylvinyldichlorosilane, γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropylmethyldimethoxysilane Release and reinforcing component (I) comprising a surface-modified synthetic silicate fine powder whose surface has been treated with 1 to 30 parts by weight of a silane compound containing an unsaturated group having a hydrophilic property (I
V) and at least 100 parts by weight of components (I), (II) and (III)
It contains 5 to 20 parts by weight of component (IV) and the molar ratio of silicon-bonded hydrogen atoms of component (II) to the total amount of unsaturated groups of components (I) and (IV) is 0.6 to 1.5. Having a releasable surface layer formed from a dimethylsilicone rubber composition produced by heat-treating an addition-reaction-type dimethylsilicone composition containing the components (I), (II) and (IV) as described above. A fixing device characterized by being formed of a body.