JP2862465B2 - Heating roller for fixing toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating roller for fixing toner used in an electrostatic copying machine or the like.

[0002]

2. Description of the Related Art A copying machine is known in which a toner image is transferred to paper or the like and then fixed. In general, in such a copying machine, the toner is transferred simultaneously with heating and pressure by passing paper or the like onto which toner has been transferred between a heating roller and a pressure roller provided in the copying machine. Fixing to paper or the like is performed. Conventionally, the heating roller includes:
A cylindrical aluminum or the like provided with a halogen lamp or the like as a heat source therein has been used.

However, since the above-mentioned aluminum heating roller has a structure in which the temperature of the surface of the heating roller is raised by radiant heat of a halogen lamp or the like provided therein, a predetermined surface necessary for fixing the entire surface of the heating roller is required. There is a problem that it takes a long time of about 1 to 10 minutes to raise the temperature, and a large heat capacity requires a large amount of electric power for heating. Therefore, Japanese Patent Application Laid-Open No. 63-15858
As disclosed in Japanese Patent Publication No. 3 (1993), a resistive heating element pattern formed on a transfer paper or the like using a thick film paste containing a metal powder and a glass binder is transferred to a surface of a metal body or the like having a ceramic or insulating film. And baking to fix the thick-film resistance heating element. According to such a technique, the heating roller directly generates heat, so that the time required to raise the surface temperature is reduced, and the power required for heating is reduced.

[0004]

However, in the technique disclosed in the above publication, the pattern of the resistance heating element is formed by printing a thick film paste, so that the surface roughness is, for example, Ra (JIS B0601). The thickness of the resistive heating element is as coarse as 1 μm or more, and the thickness is as large as 10 to 20 μm or more. For this reason, there has been a problem that heating and pressurization during fixing cannot be performed uniformly, and toner fixing unevenness occurs. Note that the unevenness due to the above film thickness can be eliminated by fixing the resistance heating element to the entire outer peripheral surface of the cylindrical insulating base so that there is no portion where the resistance heating element is not fixed. However, in such a case, the heat radiation amount differs between the central portion and the peripheral portion of the heating roller, so that a uniform temperature distribution cannot be obtained in the axial direction of the heating roller, causing a problem that toner fixing unevenness occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to obtain a relatively uniform temperature distribution in the axial direction of a heating roller and to compare heating and pressure during fixing. It is an object of the present invention to provide a toner fixing heating roller which can be uniformly performed to prevent the occurrence of fixing unevenness.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the gist of the present invention is to provide a heating device for fixing a toner in which a resistance heating element layer is formed on the outer peripheral surface of a cylindrical electrically insulating substrate. In the roller, the resistance heating element layer is formed of a metal organic compound that functions as a conductive component, and Bi, Rh, Cr, and Bi that function as components for increasing the adhesive strength between the resistance heating element layer and the electric insulating substrate. V, Sn, Pb,
Of at least one metal of B, Si, and Cd
An object is to constitute a thin film metal formed by heating a film formed on the outer peripheral surface of an electrically insulating substrate from a liquid or paste-like material containing an organic compound .

[0007]

In this manner, the organic compound of the metal functioning as the conductive component and the Bi, Rh, Cr functioning as the component for increasing the adhesive strength between the resistance heating element layer and the electrically insulating substrate are provided. , V, Sn, Pb, B, Si,
By heating a film formed from a liquid or paste-like material containing an organic compound of at least one of Cd and Cd, a relatively thin resistive heating element layer having a good surface roughness is formed. Because it is formed on the surface of the electrically insulating substrate,
The unevenness of the surface of the heating roller is reduced,
Pressurization is performed uniformly. The liquid or paste-like product comprising the metal organic compounds and the like, there is generally called resinate, simply MOC (Metal-Organic Compound)
However, in the following description, the term resinate is used. The resinate is in the form of a liquid or a paste and is extremely fine enough to allow a metal to chemically bond to an organic substance, so that a thin film thickness and a good surface roughness can be obtained. The ratio of the thickness of the resinate film after heating and fixing to the thickness after drying is 1%.
/ 5 or less, so that better surface roughness can be obtained.
Note that the resistance heating element layer obtained from the resinate film is hardly disconnected due to thermal stress during use because the metal is bonded at the atomic level, and can be used with a thin film thickness as described above. is there. In addition, since the above-mentioned resinate contains an organic compound of a metal that functions as an adhesive strength improving component in addition to an organic compound of a metal that functions as a conductive component, the action of the adhesive strength improving component causes resistance heating. High adhesion between the body layer and the electrically insulating substrate is obtained. On the other hand, when formed using a thick-film paste as in the past, the metal of the resistance heating element layer is only in contact with each other at the particle level by being bonded by the glass component, so the resistance to thermal stress is low. Therefore, it was difficult to make the thickness less than the above. Further, since the resistance heating element layer is extremely thin, even if the resistance heating element layer is formed in a pattern having a higher wiring density at both ends in order to make the temperature distribution in the axial direction relatively uniform, the resistance heating element layer may not be fixed. Even when the temperature distribution is relatively uniform by laminating the resistance heating element layer only in the central portion, the absolute value of the thickness is small. The unevenness between the portion not laminated and the portion not laminated is extremely small. Therefore, it is possible to make the temperature distribution in the axial direction relatively uniform while performing the heating and pressurization relatively uniformly, thereby preventing the occurrence of fixing unevenness.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a process flow chart for manufacturing a heating roller for fixing toner according to one embodiment of the present invention. No. 1 in Table 1
An Au (gold) -based resinate paste having the composition of No. 14 is prepared, printed on a transfer paper to a thickness of 4 to 5 μm in a predetermined pattern by screen printing, for example, and dried. Cellulose paste or synthetic acrylic paste was printed and dried to prepare a resistor transfer paper on which a resistor pattern was printed. In addition, Au
As shown in FIG. 2, the system resinate paste contains Au as a main component and Pd (palladium), Pt (platinum), Bi (bismuth), Rh (rhodium), Cr (chromium), and V as additive components. (Vanadium), Sn
(Tin), Cu (copper), Pb (lead) and the like are each dissolved and reacted with an organic compound to produce a resinate (metal-organic-compound: MO)
It is obtained by mixing and kneading C) with a borosilicate glass or lead borosilicate glass powder and a solvent such as turpentine oil or terpineol. Further, among the metals as the additive components, Bi,
Rh, Cr, V, Sn, etc. may be mixed in the form of oxide powder in addition to resinate. In addition, the above MOC
_{The, (C 7 H 15 S)} n -M, (C 12 H 25 S) n -
M (M is a metal, n represents n = 1 in .Au representing a natural number) and a metal, such as mercaptide or, -SM is bonded to any of the groups of abietic acid (C ₂₀ H ₃₀ O ₂₎ Metal resin balsam sulfide or the like is used.

[0010]

[Table 1]

Next, for example, a total length of 260 mm and an outer diameter of 10 m
m, hard glass (for example, Na ₂ O 4 .5) manufactured by drawing with a size of about 1.5 to 3.0 mm in wall thickness.
4 wt%, B ₂ O ₃ 11.9 wt%, SiO ₂ 80.
It has a composition containing 6 wt% and a small amount of Al ₂ O ₃ and an alkaline earth oxide.
cal / sec ・ cm ・ ℃, specific heat 0.23 cal / g ・ ℃, softening point 8
A glass cylinder at about 20 ° C.) is prepared, and the resistor transfer paper is cut into a predetermined size, immersed in a dissolving solution and then pasted, and the resistor pattern is transferred to the entire outer peripheral surface of the hard glass cylinder. did. The hard glass cylinder to which the resistor pattern was transferred was dried and fired to fix the first layer of the resistor pattern. Further, the second layer was fixed on the first layer in the same manner. In addition, when the resistor transfer paper is attached and transferred, a seam of the transfer paper is generated. The seam of the first layer and the second layer are located at positions different from each other by 180 ° on the outer peripheral surface. In the present embodiment, the hard glass cylinder corresponds to an electrically insulating substrate.

Next, Ag (silver) or Ag-Pd, Ag
-Prepare a Pt thick film paste, print on another transfer paper with a thickness of 10-20 μm, for example by screen printing, and dry,
Further, a top coat was applied on the Ag film in the same manner as in the above-described resistor transfer paper to prepare an electrode transfer paper. After the electrode transfer paper was cut into a predetermined size and immersed in a solution, the electrode transfer paper was attached to the outer peripheral surfaces on both ends of the hard glass cylinder to which the resistor was fixed, and the electrodes were transferred. This is dried and fired under predetermined conditions to be fixed, and a fluororesin (for example, polytetrafluoroethylene) film having a thickness of about 20 to 25 μm is formed on the outer peripheral surface of the hard glass cylinder to which the resistor is fixed. Thus, a toner fixing heating roller 10 as shown in FIG. 3 was obtained. As shown in FIG. 3, the toner fixing heating roller 10 obtained as described above has a pair of electrodes 14 on both ends thereof on the outer peripheral surface of the hard glass cylinder 12.
A resistor 16 and a fluororesin film 18 covering the resistor 16 are fixed to an intermediate portion of the resistor 4. The resistor 16 is formed in a spiral shape and both ends are connected to the electrode 14. The fluororesin film protects the resistor when heated and pressurized in a copying machine and also prevents toner from adhering.

FIG. 4 is a diagram schematically showing a cross section of a main part of a toner fixing section of a copying machine to which the above-mentioned toner fixing heating roller is applied. In the figure, the toner fixing heating roller 10 and a pressure roller 28 having a silicone rubber 26 fixed to the outer peripheral surface of an aluminum cylinder 24 are shown in housings 20 and 22 fixed at predetermined intervals vertically. The heating roller 10 for fixing toner and the pressure roller 28
Are pressed against each other with a predetermined force. The distance between the inner peripheral surface of the housing 20 and the outer peripheral surface of the heating roller 10 for toner fixing is as small as about 1 mm, and a thermoelectric hole is formed through the inner peripheral surface from the outside of the housing 20. The pair 30 is attached, the internal temperature is detected, the voltage applied to the toner fixing heating roller 10 is controlled by a control circuit (not shown), and the surface temperature is maintained at an appropriate temperature. . When the paper 32 or the like onto which the toner has been transferred by the transfer device (not shown) is fed in from the carry-in port 34, the paper 32 is heated and pressurized between the toner fixing heating roller 10 and the pressure roller 28.
Thus, the toner is fixed.

Here, the toner fixing heating roller 10
The following evaluation was performed to confirm the heating performance of. In addition,
The basic characteristics are No.5 which has good adhesion to hard glass
Was measured using an Au-based resinate paste.
As a result, the thickness of the electrode portion was d ≒ 15 μm, and the resistivity was ρ ≒
8 × 10 ⁻⁵ Ω · cm (that is, sheet resistance value R _S ≒ 5)
0 mΩ / □), the thickness of the resistor portion is d ≒ 0.5 μm, the surface roughness is 0.05 to 0.3 μm in Ra, and the resistivity ρ ≒ 1.3.
× 10 ⁻⁴ Ω · cm (that is, sheet resistance R _S ≒ 2.6)
Ω / □), and the total resistance of the heating roller 10 for toner fixing (that is, the resistance value between the pair of electrodes 14) was 19.7 Ω. Next, a voltage was applied to the electrodes 14 at both ends to evaluate the temperature rise characteristics. As a result, when a voltage of 90 V (ie, 411 W) or more is applied as shown in FIG. 5, a predetermined temperature, that is, a temperature of 180 ± 20 ° C. necessary for toner fixing is reached within 10 seconds, and a voltage of 70 V (ie, 2
It was confirmed that a predetermined temperature was reached in about 12 seconds even at a voltage of about 50 W) and about 30 seconds at a voltage of about 50 V (that is, 127 W).

That is, in the toner fixing heating roller 10 of the present embodiment, since the resistor 16 is composed of a thin film metal formed of a resinate film, the resistor 16 is formed in a pattern as shown in FIG. However, the irregularities of the portion where the resistor 16 is fixed and the portion where the resistor 16 is not fixed are only the thickness of the resistor 16, that is, about 0.5 μm, and the resinate paste is composed of extremely fine metal particles. Since the above-described good surface roughness is obtained, the amount of heat and pressure applied to the paper or the like when heating and pressing the paper 32 or the like onto which the toner has been transferred become relatively uniform, That is, toner fixing unevenness is avoided. In the pattern of the resistor 16 shown in FIG. 3, the density at the end of the resistor 16 is made higher than that at the center to compensate for the amount of heat radiation at the end of the heating roller 10 for toner fixing. Although it is formed so as to obtain a uniform temperature distribution, the unevenness due to the pattern of the resistor 16 is extremely small as described above. Can be made relatively uniform.

Further, as described above, since the resistor 16 is extremely thin, a relatively small amount of metal is used, so that the toner fixing heating roller 10 can be obtained at a relatively low cost.

In this embodiment, Au is a conductive component, additives Pd and Pt are high-resistance conductive components, and Bi, Rh, Cr, V and Sn have an adhesive force with a hard glass cylinder. Borosilicate glass or lead borosilicate glass is added as a component that increases the resistance of the resistor and also increases the adhesive strength of the resistor to the hard glass cylinder 12 as a component that increases the mechanical strength of the resistor. .

Next, another embodiment of the present invention will be described.

In the same manner as above, except that the Au-based resinate paste of the composition of No. 1 to No. 4 in Table 2 was used instead of the Au-based resinate paste of the above-described embodiment, the thickness was 5 to 7 μm. A resistor transfer paper having the resistor paste printed thereon was prepared. The Ru-based resinate paste is composed of Ru as a main component, Pb (lead) as an additive component,
Except for using B (boron), Si (silicon), Bi, etc., it is obtained in the same manner as in the above embodiment. Also, in this embodiment, the same MOC as in the above embodiment is used. However, as the MOC of Ru, Ru octanoate [(C ₈ H ₁₅ COO) ₃ Ru] is used in place of metal resin balsam sulfide. As the mercaptide, those having n = 3 in the above chemical formula are used.

[0020]

[Table 2]

Next, a hard glass cylinder similar to that of the above embodiment is prepared, and the resistor transfer paper is cut into a predetermined size, immersed in a dissolving solution, and then pasted. Then, the resistor was transferred. The hard glass cylinder to which the resistor was transferred was dried and fired to fix the first layer of the resistor. Further, the second layer of the resistor was fixed to the center of the first layer in the same manner.

Next, in the same manner as in the above embodiment, the electrodes were fixed, and a fluororesin film was formed to obtain a toner fixing heating roller 36 as shown in FIG. As shown in FIG. 7, the heat roller 36 for fixing the toner has a pair of electrodes 40 at both ends on the outer peripheral surface of the hard glass cylinder 38 and a fluororesin film 42 at an intermediate portion between the pair of electrodes 40. The two-layered resistors 44 are fixed to each other. The first layer resistor 44a is provided so as to cover between the pair of electrodes 40 of the hard glass cylinder 38,
It is connected to the. On the other hand, the second layer resistor 44b is provided so as to have a predetermined interval as shown in the figure between the second resistor 44b and the end of the electrode 14, and the center of the resistor 44 is thicker than the end. For example, the center is about 1.5 μm and the end is about 0.5 μm. Also in this embodiment, the surface roughness of the resistor 44 is 0.05 to 0.15 in Ra.
It was as good as about μm.

The toner fixing heating roller 36 also has the same characteristics as those of the above-described embodiment, and can be used in a similar copying machine. By making the portion thicker than the portion, the temperature distribution in the axial center direction is made substantially uniform.

In this embodiment, Ru is a conductive component, and additives Pb, B, Si, and Bi are components that increase the adhesive strength with the hard glass cylinder 38 and increase the mechanical strength of the resistor 44. It has been added as.

While the embodiment of the present invention has been described in detail, the present invention can be embodied in still another embodiment.

For example, the resinate paste for forming the resistors 16 and 44 is not limited to the Au-based resinate paste and the Ru-based resinate paste of the embodiment, but Pt, P
Other conductive components such as d and Ag may be used as main components, and Cd (cadmium) or the like may be used as an additive component. Each component can be mixed in the form of a metal oxide powder or simply a metal powder in addition to a resinate form as long as the properties as a toner fixing heating roller are not impaired. It should be noted that the smaller the amount of powders added, the greater the shrinkage during firing, and the effects of the present invention can be further expected.

In addition to the hard glass 12, 38, ceramics such as alumina, mullite, and zirconia, and metals having an insulating film such as aluminum and stainless steel can be used as the electrically insulating substrate. However, in the present invention, since heat is generated on the surface of the electrically insulating substrate, it is preferable to use a material having a low thermal conductivity so as not to impair the speed of the surface temperature rise due to heat radiation, which is used in Examples. Low thermal conductivity materials such as hard glasses 12, 38 and zirconia are desirable.

In the embodiment, the resinate is formed by laminating two layers (however, partially in the second embodiment), but may be formed by one layer, or conversely, may be formed by laminating three or more layers. . The number of laminations is appropriately determined according to the required film strength, resistance value, heat generation characteristics, and the like.

The resinate film may be formed on the electrically insulating substrate by a dry transfer method or a direct printing method on the electrically insulating substrate by a curved surface printing machine, in addition to the wet transfer method shown in the embodiment. Is also good.

Further, in the embodiment, in order to avoid a reaction at the time of firing the resistor and the electrode, a step of separately preparing the resistor transfer paper and the electrode transfer paper, and sequentially transferring and firing the same was employed. If a material that does not cause a problem during firing is used for the resistor and the electrode, both can be printed on a single sheet of transfer paper to simplify the transfer and heating process.

Although not specifically exemplified, the present invention can be variously modified without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a process flowchart showing a manufacturing process according to an embodiment of the present invention.

FIG. 2 is a process flow chart showing a manufacturing process of a resinate paste used in the process of FIG.

FIG. 3 is a diagram showing an example of a toner fixing heating roller manufactured by the process of FIG. 1;

4 is a diagram schematically illustrating a cross section of a main part of a toner fixing unit of an electrostatic copying machine to which the toner fixing heating roller of FIG. 3 is applied;

5 is a diagram showing surface temperature characteristics when a voltage is applied to the toner fixing heating roller of FIG. 3;

FIG. 6 is a view showing another example of the toner fixing heating roller of the present invention.

FIG. 7 is a diagram schematically illustrating a cross section of the heating roller for fixing toner in FIG. 6;

[Explanation of symbols]

 10: Heating roller for fixing toner 12: Hard glass cylinder (electrically insulating substrate) 14: Electrode 16: Resistor 18: Fluororesin film

Continued on the front page (72) Yoshiharu Ogawa 3-36 Noritake Shinmachi, Nishi-ku, Nagoya City, Aichi Prefecture Inside Noritake Company Limited (72) Inventor Masato Sano 3-1-1 Noritake Shinmachi, Nishi-ku, Nagoya City, Aichi Prefecture No. Noritake Co., Ltd. (72) Inventor Tatsuo Kono 2160, Yatsu-cho, Yasu-cho, Asakura-gun, Fukuoka Prefecture 2160 Kyushu Noritake Co., Ltd. (56) References JP-A-55-164862 (JP, A) JP-A-2-227909 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 13/20 G03G 15/20 H05B 3/00 335 F16C 13/00

Claims (1)

(57) [Claims] 1. A heating roller for fixing a toner in which a resistance heating element layer is formed on the outer peripheral surface of a cylindrical electrically insulating substrate, wherein the resistance heating element layer is formed of an organic metal compound that functions as a conductive component; Bi, R functioning as a component for increasing the adhesive strength between the resistance heating element layer and the electrically insulating substrate.
a film formed on the outer peripheral surface of the electrically insulating substrate from a liquid or paste containing an organic compound of at least one metal among h, Cr, V, Sn, Pb, B, Si, and Cd A heating roller for fixing the toner, comprising a thin film metal formed by heating the toner.