JPS62153983A - Production of elastic rotating body and elastic rotating body - Google Patents

Abstract

PURPOSE:To additionally increase the adhesive power between elastic material layers and resin layers by calcining a resin material on the elastic material layers while maintaining the elastic material layers at the temp. lower than the temp. of the resin liquid coated thereon and heating the resin material at a high temp. at which said material can be calcined thereby forming the resin layers on the elastic materials. CONSTITUTION:The uncalcined fluoroplastic, for example, a dispersion perpd. by dispersing fluoroplastic powder in water by a surface active agent is coated on the surfaces of the elastic rotating bodies 1, 2 over the entire length of the elastic rotating bodies to a uniform thickness by a method such as spray painting, electrostatic painting or powder painting. While the elastic rotating bodies themselves are maintained under heating at the low temp. to obviate the generation of fuming and depolymn., the coating layers of the fluoroplastic are heated to the high-temp. state above the crystal m.p. thereof to form the film-like resin films 13, 23. The adhesive power between the elastic material layers and the resin layers is thereby improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a general elastic rotating body, particularly an elastic rotating body having a resin layer on the elastic body, and further relates to a method for manufacturing the elastic rotating body. The elastic rotating body according to the present invention is optimally used, specifically as a paper conveyance roller or belt in office equipment, particularly as a heat fixing roller or belt.

(Background Art) Conventionally, many elastic rotating bodies in which a resin layer is provided on an elastic body have been proposed. These are considered important in the field of fixing devices, but all of them have low adhesion between the elastic layer and the resin layer.
It had poor durability and wear resistance during use, and although it could be put to practical use, the replacement period was short.

In addition, the resin layer provided on the elastic layer cannot have excellent wear resistance unless it is fired at a high temperature that is lower than the durability temperature of the elastic layer. Nothing satisfied me sexually.

In contrast, as stated in the patent application, the applicant maintains the rubber elastic layer under heating at a low temperature that does not cause smoke or depolymerization due to heating. We have proposed an elastic rotating body obtained by firing a resin layer coated on the resin layer at a high temperature above its crystal melting point. According to this, it has surface resin properties, has appropriate elasticity as a whole, and is also superior to conventional elastic rotating bodies in terms of fixing properties, abrasion resistance, and mold release properties.

(F'1le42899) However, even when this elastic rotating body was manufactured, the adhesion between the elastic layer and the resin layer was still insufficient and was not satisfactory.

(Object of the Invention) An object of the present invention is to provide a method for manufacturing an elastic rotating body that can further strengthen the adhesion between the elastic layer and the resin layer, and the elastic rotating body obtained thereby. be.

(Summary of the Invention) The present invention achieves the above object by pre-containing a surfactant material gold on the surface of an elastic body, and completely applying a resin liquid obtained by mixing an unfired resin material onto the elastic body, After that, this resin liquid material is also applied to the elastic layer while maintaining it at a low temperature.
In addition, the resin material is fired on the elastic body while being heated to a high temperature at which it can be fired, thereby forming a resin layer in close contact with the elastic body.

(Embodiment) FIG. 1 is an explanatory diagram of an embodiment of a fixing device of the present invention having a fixing roller which is an elastic rotating body of the present invention.

In Fig. 1, 1 is the fixing roller on the side that comes into contact with the unfixed toner iron, 2 is the pressure roller that rotates in pressure contact with the fixing roller L,
Both are examples of the fixing roller of the present invention. The specific configuration is as follows.

The fixing roller 1 is made of relatively thin silicone rubber (0.3 mm in this example) on a core metal 11 made of aluminum or the like with good heat conduction.
(predetermined thickness within the range of 0.8 mm), rebound modulus is 65
% to 85 cm, and the upper layer 13 is made of a fluororesin such as PFA resin (tetrafluoroethylene resin; copolymer of perfluoroalkoxyethylene resin), PTF'B (tetrafluoroethylene resin), etc. The elastic layer 12 is also thin (12 in this example).
Predetermined thickness within the range of 0μm to 25μm) Film strength is 5okg
/crA or more as a resin layer. Similarly, the pressure roller 2 has a silicone rubber elastic layer 12 on a core metal 21 made of stainless steel, iron, etc., which is thick and relatively thick (in this example, a predetermined thickness in the range of 4 mm to 10 mm), and has a silicone rubber elastic layer 12 that is thick and relatively thick (in this example, a predetermined thickness within the range of 4 mm to 10 mm), and has a resilient silicone rubber layer 12 that has a relatively thick silicone rubber elastic layer 12 on a core bar 21 made of stainless steel, iron, etc. Elastic body N22 with a modulus of 65% to 85% and PF on the upper layer
A, fluororesin such as PTFB is made thinner than the thickness of the thick elastic layer 22 (in this example, a predetermined thickness within the range of 5μ to 35μ);
It has 23 resin layers with a film strength of 50 to 9/crl or more.

These rollers 1, 2 are formed by the manufacturing method shown in FIG. 3 or by a method consistent with the purpose thereof. Briefly, it includes the following steps.

A silicone rubber layer vulcanized and molded on the core metal (thermal conductivity 1
．． 4 X 10-'~1.5 X l O"C11l
++cm/secsCml/°C] to make a silicone rubber rod of the desired shape. A preferred shape is an inverted crown type in which the center portion is slightly smaller in diameter than the opposite ends. An unfired fluororesin such as dispersion (fluororesin powder dispersed in water with a surfactant), enamel, or powdered fluororesin is applied to the surface of this rubber roller over the entire length of the rubber roller by spray coating, electrostatic coating, or powder coating. Apply to a uniform thickness by painting or other methods. This dispersion has a glass transition point of 32, which is the crystalline melting point of fluororesin, for example.
A film-like resin coating is formed by heating to 7°C or higher.

For this reason, silicone rubber rollers coated with unfired fluororesin must be heated above the crystal melting point (PTFE is above 327°C, PFA is above 327°C,
must be heated to a temperature of 306°C or higher).

However, although silicone rubber itself has excellent rubber properties such as rebound modulus and compression set, it smokes and depolymerizes when heated above 300°C, especially above 306°C or 327°C. These things not only hinder the formation of a high-quality fluororesin layer, but also cause the silicone rubber itself to lose its rubber properties.

Therefore, overheating of the rubber layer causes the rubber layer to lose its function and the resin layer to lose its properties, thereby losing the conditions necessary for fixing.

For these reasons, in the embodiments of the present invention, the silicone rubber roller itself was heated at a low temperature (300°C or less at most) that would not cause smoke or depolymerization, while the fluororesin coating layer was coated with its crystals. We adopted a firing method that provides a high temperature state above the melting point.

Specifically, there is a method in which the rubber layer is rapidly cooled from inside the core metal while rapidly heating the unfired fluororesin on the surface, or the dielectric loss tangent of the liquid fluororesin (dispersion, enamel) itself is the same as the dielectric loss tangent of the rubber layer. In addition to the dielectric heating method that utilizes the larger size (see FIG. 3), any method that meets this purpose is suitable for the present invention.

Although this method essentially forms a thermal gradient in the silicone rubber in the direction of its base,
℃, but the temperature of unsintered fluororesin iK is higher than its crystal melting point (specifically, 340℃ to 327℃ or higher for PTFE).
A firing temperature of 80° C. is applied for about 5 to 10 minutes. After the entire firing process, the roller is rapidly cooled. During this rapid cooling process, the crystallinity is 95 degrees or less, the tensile strength is 50, and the contact angle with water is 10 or more.
The baked fluororesin surface layer exhibiting resin properties of 0 degrees or more is formed in a sufficiently thick state and in strong adhesion to the rubber roller.

Therefore, the fixing roller 1. In heating roller 2, the lower layer silicone rubber itself exhibits the desired rubber properties almost the same as before the formation of the entire resin layer, and the surface fluororesin layer exhibits completely baked resin properties, and the adhesiveness of these layers is strong. It is.

Now, returning to FIG. 1, another configuration of the fixing device will be explained.

3 is for heating the fixing roller from inside.

The fixing roller surface temperature is determined by a heater 3, a temperature detection element 4, and a control means 31, such as a heater such as a halogen lamp.
60°C to 200°C).

Reference numeral 5 denotes an anti-offset liquid applying means which also serves as a cleaning means for applying an anti-offset liquid such as silicone oil to the surface of the fixing roller. The application means 5 may be felt-like, but in this example a web is used. The web 51 containing the anti-offset liquid is
An elastic suppression roller 52 made of silicone sponge or the like is brought into contact with the fixing roller, and a small amount of anti-offset liquid is applied to the surface of the fixing roller. Further, the web 51 is gradually wound up from the supply roller 54 by a winding roller 53, and the contact surface of the web to the fixing roller can be sequentially determined by a control means (not shown).

The recording paper P carrying the unfixed toner (T) is guided by the one-person log guide 6 and passes between the pair of rollers 1 and 2. The separation claw 41 that comes into contact with the roller surface is provided to separate the recording material from the roller surface 1.

The fixing roller 2 formed in this manner has a roller characteristic that did not exist in the past, namely, it has sufficient rebound elasticity because the fluororesin is completely baked without deteriorating the silicone rubber properties due to heat. It enables the use of silicone rubber with low compression set, and is highly durable with excellent surface releasability, abrasion resistance, and sufficient elasticity. Moreover, even if the stress generated when toner particles are fixed on the recording paper is concentrated between the silicone rubber layer and the fluororesin layer, the strength of the fluororesin layer is high and the adhesion between them is also good.

Other characteristics of the above configuration are as shown in FIG. 2: the thickness t3 of the elastic layer 12 of the fixing roller, the thickness t3 of the resin layer 13 of the fixing roller, and the thickness t of the elastic layer 22 of the pressure roller.
1 and the thickness t4 of the resin layer 23 of the pressure roller.

That is, for roller 1: j l> t* for roller 2: 1. )1°, preferably t4<1. <1゜With this configuration, basically, the fusing roller and the pressure roller have mutual effects, which compensate for each other's shortcomings and improve each other's advantages.
The obtained image quality and fixing properties can be excellent, and the durability can be excellent.

By the way, for a fixing roller having the above-mentioned characteristics, the things that most affect the durability are the film strength of the fluororesin layer and the adhesion between the fluororesin and the silicone rubber layer. In order to strengthen the adhesion of the rubber layer, the unfired fluororesin must first be wetted uniformly and sufficiently onto the rubber layer, and the inventors of the present invention have found a means for this purpose.

That is, when PTFB'e is coated on silicone rubber with a small surface energy, for example, it is impossible to form a uniform and strong coating film because the PTFE dispersion is repelled. However, the inventor of the present invention added a silicone-based surfactant to the surface layer of the elastic body by injecting a silicone-based surfactant into the silicone rubber, or by adding a step of rubbing the surfactant onto the surface layer after the elastic body layer was completed. By allowing the presence of surfactants, 弗□
S$4 We succeeded in completely reducing the wettability of the tispersion and improving its adhesion to the elastic layer.

PJ t C. When forming the silicone rubber layer, the polyether-modified silicone oil is completely mixed into the rubber comparand and when vulcanization molding, the surfactant is exposed on the 5th surface layer. Therefore, it has good affinity with the surfactant contained in the fluororesin dispersion, and a uniform layer of the fluororesin dispersion is formed on the silicone rubber layer.

Then, when it is fired, it is heated.

The surfactant from inside the silicone rubber comes out of the roller, creating voids there, and conversely, the fluororesin dispersion penetrates into those voids, which strengthens the adhesion between the silicone rubber layer and the fluororesin layer. becomes even stronger.

Further, a surfactant such as the same polyether f-based silicone oil may be rubbed onto the surface layer of the silicone rubber using a scrubbing brush such as Plan or Scotch Brite ■ (product name). In this case, the silicone rubber surface layer is finely scratched, and the surfactant enters into the scratches, which improves its affinity with the fluororesin dispersion applied to the surface layer, making it possible to form a uniform coating over the entire surface layer. Furthermore, when this is fired, the fluororesin sufficiently penetrates into the fine irregularities of the rubber surface layer, similar to when the surfactant is completely mixed into the rubber, so that strong adhesion can be obtained.

Next, FIG. 3 shows a method of firing the fixing roller. The device shown in the figure is a specific example of a heating method that uses both a dielectric heating device and infrared external heating.
~2450MH2)k A waveguide 106 for propagating waves, an openable and closable resin container 102 to which the waveguide is connected and has a metal high-frequency reflection plate 103 on its inner surface, and two infrared rays on the top and bottom for external heating. It has a lamp 111 and a reflective shade.

Inside the resin container 102, a fan 100 that generates an air flow inside the hollow of the fixing roller 1 as a fixing roller, and a fan 101 that generates an air flow inside the container 102 are installed, respectively. It is rotatably provided by a drive. This container can be opened and closed at the top and bottom around a fulcrum 108, and has a handle 109 on the top and a flange IA of the roller 1 on the bottom.
Arms 107 for positioning Th are fixedly provided.

Reference numeral 110 denotes a control means of the apparatus, which operates the driving means 104, the magnetron 105, and the infrared lamp 111 according to the closed state of the container and the manual input of a predetermined start signal, using a variable timer shown in a quantum diagram for a predetermined time.

Since the fixing roller 1 has a silicone rubber layer on the lower layer and a fluororesin dispersion on the surface, a large amount of high frequency waves are absorbed in the silicone rubber layer as well as in the dispersion having a high dielectric constant. Therefore, the fluororesin dispersion is rapidly heated to 340° C. to 350° C. by heating using high frequency waves, infrared rays, and a constant temperature bath. At this time, since the silicone rubber layer has a low high frequency absorption rate, the dispersion is not heated to a high temperature, but is heated to a temperature below about 280°C.

This allows the roller characteristics described above to be improved.

In the above examples, the fluororesin resin is, for example, tetrafluoroethylene resin Disbae 4-John D-1 manufactured by Daikin Corporation.

In the present invention, when the film thickness of resin I- (rloμ or more) is made, the durability can be improved to more than 250,000 sheets, and when it is made more than 15μ, the durability can be improved to 3
Durability of 100,000 sheets or more is obtained, and a high degree of fixing performance can be maintained by compensating for the drawback that the fixing effect decreases with increase in thickness by the repulsion modulus of the entire rubber layer. The present invention is particularly effective when a fluororesin is provided on a silicone rubber layer.

In addition to the above-mentioned embodiments, the present invention also includes a roller-shaped fixing roller, a belt-shaped roller (for example, an intermediate belt for simultaneous transfer and fixing), and a cleaning roller.

Contains a release agent supply roller and the like. In particular, it has excellent transferability due to the mold releasability and elasticity of fluororesin.

It has excellent abrasion resistance and is easy to clean (as an FC cleaning roller, it cleans according to the surface energy level, etc.), and the elastic VCL tracing effect prevents uneven application of mold release agent and uneven transfer. Advantages: Can be used in all kinds of applications.

Further, although FIG. 1 above shows all the examples of the heat fixing device and shows the preferred embodiment of the present invention, toner can be fixed by applying light pressure! The present invention can also be applied to a pressure fixing device that performs pressure fixing, a pressure fixing device that performs simultaneous transfer and fixing, or a heat fixing device.

Further, although the above example has a two-roller configuration, the fixing device may include a heating roller, a pressure roller, a release agent supply roller, a cleaning roller, or other belt-like rollers in a fixing device having three or more rollers. Apparatus are also included in the invention.

The effect of using the elastic rotating body of the present invention as a fixing roller is that it has excellent abrasion resistance and surface releasability, and fully utilizes the surface characteristics of the resin layer and the elastic characteristics of the rubber, which makes it easier to use the toner particles. It also has an excellent patterning effect on other rollers and has an extremely long life.

(Effects of the Invention) As described above, according to the present invention, the adhesion between the elastic body layer and the resin layer can be improved, and an elastic rotating body with more excellent durability can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an example of a fixing roller (including a belt-shaped roller) and a fixing device including the fixing roller according to an embodiment of the present invention, FIG. 2 is a partially enlarged explanatory diagram of the fixing roller, and FIG. FIG. 2 is an explanatory diagram of an embodiment of a method for manufacturing a fixing roller. 1 is a fixing roller, 2 is a pressure roller, 12 and 22 are silicone rubber elastic layers, and 13 and 23 are fluororesin layers.

Claims (2)

[Claims] (1) In a manufacturing method for manufacturing an elastic rotating body having a resin layer on the elastic body, the surface of the elastic body contains a surfactant in advance, and an unfired resin material is mixed on the elastic body. A resin liquid is applied to the elastic layer, and then the elastic layer is heated to a temperature higher than that of the resin liquid while being heated to a high temperature at which the resin material can be fired, and the resin is coated onto the elastic layer. A method for manufacturing an elastic rotating body, characterized by forming layers in close contact with each other. (2) An elastic body whose surface has been made to contain a surfactant in advance, and a resin liquid made by mixing an unfired resin material on this elastic body are applied, and then this resin is applied to the elastic body layer. What is claimed is: 1. An elastic rotating body comprising a resin layer formed by firing an elastic body while maintaining the temperature at a lower temperature than that of a liquid body and heating the resin material to a high temperature at which the resin material can be fired.