JPH0744051A - Oil applying member - Google Patents

Abstract

PURPOSE:To provide an oil applying member which applies a proper amt. of oil to a fixing roll or press roll and is hardly changed in the amt. of the oil to be applied and the oil applying member which prevents the leakage of the oil even after long-term preservation. CONSTITUTION:This oil applying member has a microporous film layer 8 consisting of a polytetrafluoroethylene resin, etc., on the outer side of an oil holding layer 7 consisting of a fiber sheet mainly composed of fibers of <=10mum fiber diameter. An elastic material layer 9 consisting of a felt, etc., is formed on the outer side of the microporous film layer 8 of the oil applying member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a member for applying oil to a fixing roll or a pressure roll of a copying machine, a printer, a facsimile or the like.

[0002]

2. Description of the Related Art In a copying machine, a printer, a facsimile or the like, as shown in FIG. 1, a toner 5 is transferred by passing a paper 5 on which a toner 4 is transferred between a fixing roll 1 and a pressure roll 2. However, the toner 4 remains on the fixing roll 1 at the time of fixing, causing an offset problem. Therefore, a means is adopted in which the toner 4 is prevented from remaining by applying oil to the surface of the fixing roll.

For example, Japanese Unexamined Patent Publication Nos. 61-160780 and 61-183679 disclose an oil application member in which a nonwoven fabric or a heat-resistant felt is coated with a microporous film such as tetrafluoroethylene resin on the outside. There is. However, the oil application members disclosed in these publications are uneconomical because the amount of oil applied to the fixing roll is much larger than the required amount, and not only cannot be used for a long period of time, but also with time. Since the amount of oil applied tends to change, there is a problem that oil cannot be applied stably. Further, if these oil application members are stored at room temperature, the oil leaks out, the surroundings are soiled, and the hands are soiled when the oil application member is installed, resulting in poor workability.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. A first object of the present invention is that the amount applied to a fixing roll or a pressure roll is appropriate and The second purpose is to provide an oil application member in which the amount of oil applied does not easily change.
An object of the present invention is to provide an oil application member in which oil does not leak.

[0005]

The oil application member of the present invention has a microporous membrane layer on the outside of an oil retaining layer made of a fiber sheet containing fibers having a fiber diameter of 10 μm or less. In addition, when the elastic body layer is provided outside the microporous membrane layer,
It is an oil application member that does not leak oil and can be stored for a long period of time.

[0006]

The oil-applying member of the present invention has an oil-retaining layer made of a fiber sheet containing fibers having a fiber diameter of 10 μm or less. Since the oil-retaining property is good, a fixing roll or a pressure roll (hereinafter referred to as a coating target) (Sometimes referred to as a product) can be applied in an appropriate amount. Further, since the oil application member of the present invention has the microporous membrane layer outside the oil retaining layer, even if the amount of free oil from the oil retaining layer increases, the coating amount can be controlled by the microporous membrane layer. Therefore, the amount of oil applied is unlikely to change.

The fiber sheet constituting the oil-retaining layer of the present invention contains fibers having a fiber diameter of 10 μm or less and forms many small spaces, and is therefore considered to be excellent in oil-retaining property. If this fiber diameter exceeds 10 μm,
Since the oil retaining property is poor, it is necessary to include fibers having a fiber diameter of 10 μm or less. Fibers having a fiber diameter of 10 μm or less are preferably at least 5% by weight or more, and 5% by weight or more.
If it is less than the above range, the oil retaining property is deteriorated. More preferably, it is 10% by weight or more.

The fiber diameter means the length of a straight line which can be taken longest in the fiber cross section. For example, when the fiber cross section is elliptical, it is the length of the major axis, when the fiber cross section is triangular, it is the length of the longest side, and when the fiber cross section is the quadrangle, it is the longer length of the diagonal line. .

Such fibers can be obtained by, for example, a so-called melt-blowing method in which fibers are split by mechanical and / or chemical treatment, or fibers are spun and at the same time air is applied to make the fibers fine.

Examples of the above-mentioned fibers that can be divided include:
Sea-island fibers with cross-sections in which one component is arranged in another island, multiple bimetal fibers with cross-sections in which different components are alternately laminated in layers, or chrysanthemum flowers with cross-sections in which one component is arranged in another component There are type fibers. As a combination of resin components constituting the divisible fiber, for example, polyamide resin and polyester resin, polyamide resin and polyolefin resin, polyester resin and polyolefin resin, polyester resin and polyacrylonitrile resin, polyamide Resins and polyacrylonitrile resins, polyolefin resins and polyacrylonitrile resins, polyolefin resins, polyester resins, and the like.

The fiber length (hereinafter sometimes referred to as fiber density) per unit volume of the fiber sheet constituting the oil retaining layer of the present invention is 1,500 m / cm ³ or more, more preferably 4,000 m / cm ³ or more. In this case, since the oil retaining property is good, the fiber sheet in this range can be preferably used. The fiber density can be calculated by the following formula. In the formula, M is the basis weight of the fiber sheet (g / cm ² ), D is the thickness of the fiber sheet (cm), ρ is the specific gravity of the fiber, and S is the cross-sectional area of the fiber (cm ² ).

When the fiber sheet is composed of plural kinds of fibers, the basis weight is distributed according to the weight ratio, the fiber density is calculated for each fiber, and the sum is taken as the fiber density. For example, the fibers constituting a fiber sheet having a basis weight of 50 g / m ² and a thickness of 5 mm are 40% by weight of a polyester fiber having a specific gravity of 1.38 and a fiber radius of 3 μm, and a specific gravity of 1.14 and a fiber radius of 4
When composed of 60% by weight of polyamide fiber of μm, the fiber density is 0.005 × 0.4 / {0.5 × 1.38 × π × (3
× 10 ^-4 ) ² × 100} + 0.005 × 0.6 / {0.5 ×
1.14 × π × (4 × 10 ⁻⁴ ) ² × 100} = 100 + 1
It becomes 00 = 200 (m / cm ³ ).

Examples of the fibrous sheet include non-woven fabrics, woven fabrics, and knitted fabrics. Among them, non-woven fabrics having a three-dimensional structure, forming many minute spaces, and more easily holding oil are available. It can be preferably used. As the method for producing this non-woven fabric, for example, a card method, an air lay method, a fiber web obtained by a wet method, etc., a method of entanglement of fibers by applying a water stream or a needle, a method of bonding with an adhesive, a constitution There are a method of bonding by fusion of fibers, a method of spinning fibers and at the same time a melt blow method in which air acts. In addition, if the fibers that can be divided are used and the fibers are entangled with each other by water flow or needle punching, the fibers can be divided at the same time, which is advantageous in the manufacturing process.

An oil retaining layer of the present invention is formed by retaining oil such as dimethyl silicone oil, methylphenyl silicone oil, and modified silicone oil such as alkyl modified or methylstyryl modified on such a fiber sheet. The viscosity of oil (at 25 ° C., the same below) may be 100 to 30,000 centistokes (sometimes referred to as CS),
Even if the oil has a low viscosity of three orders of magnitude, it is possible to apply an almost constant amount of oil. The amount of oil retained may be appropriately changed depending on the type of fiber sheet or oil, or the object to be coated used.

In the present invention, the microporous membrane layer is formed outside the oil retaining layer as described above. This microporous membrane layer is a layer that regulates the amount of oil applied, and even if a large amount of oil is released from the oil retaining layer, the amount of oil applied can be controlled by this microporous membrane layer.

Examples of the microporous film include a microporous film made of a fluorine resin such as polytetrafluoroethylene, an olefin resin, and a urethane resin. Among these, a microporous film made of a fluororesin-based resin having excellent heat resistance can be preferably used. The physical properties of these microporous membranes include, for example, a pore diameter of 0.1 to 10 μm and a porosity of 10 to 10.
60% film thickness of 0.05-5 mm can be used,
It may be appropriately changed depending on the amount of oil in the oil retaining layer, the material to be oiled, and the required amount of oil applied.

As described above, the oil applying member of the present invention basically comprises the oil retaining layer and the microporous membrane layer. As shown in the sectional views of the oil applying member in FIGS. Inside the layer 7 and / or outside the microporous membrane layer 8, for example, sponge such as silicone sponge or urethane sponge, regenerated fiber, semi-synthetic fiber, synthetic fiber, plant fiber,
The elastic layer 9 such as felt, woven fabric, or knitted fabric made of fibers such as animal fibers may be formed. When the elastic body layer 9 is formed inside the oil holding layer 7, the elastic body serves to make the pressing force on the object to be coated uniform, so that the amount of oil applied can be made more uniform or the elastic body layer 9 If oil is retained, more oil can be retained and it can be used for a longer period of time.

Further, when the elastic layer 9 is formed on the outer side of the microporous membrane layer 8, the elastic layer 9 can also hold the oil, so that the oil leaks out and stains the surroundings, or when the oil applying member is installed, There is no problem such as soiling. Further, since the microporous film does not directly contact the object to be coated, the microporous film is protected from damage and the toner does not block the micropores of the microporous film. This can be performed stably, and the oil application member can be used for a longer period of time. Furthermore, since the elastic layer 9 can also act as a heat insulating layer, there is a feature that a fiber sheet having poor heat resistance can be used as an oil holding layer.

Here, the felt will be described in more detail. As the fibers constituting the felt, since the surface temperature of the object to be coated is generally about 100 to 220 ° C., a part or all of the heat resistant fibers such as aromatic polyamide fibers and polyimide fibers are used. Is more preferable.

As a method for producing this felt, for example, a fiber web obtained by a card method, an air lay method, a wet method or the like is entangled with each other by applying a water stream or a needle, and is bonded with an adhesive. There are a method, a method of bonding by fusion of constituent fibers, or a melt blow method in which fibers are spun and at the same time air is acted.

The obtained felt preferably has a larger fiber diameter and a smaller fiber density than the fiber sheet constituting the oil retaining layer. This is because if the felt forming the elastic layer 9 has a smaller fiber diameter than the fiber sheet forming the oil retaining layer and the fiber density is high, the oil easily exudes due to a capillary phenomenon, and the excess oil is needed. This is because it is easy to apply oil and oil drops.

In the state of fiber web or felt, 2
It is also possible to stack more layers. For example, a laminate of felt having a dense structure and felt having a rough structure can be used as the elastic layer 9.
In this case, as described above, if the felt surface having a dense structure has a smaller fiber diameter than the fiber sheet forming the oil retaining layer and the fiber density is high, the oil easily exudes due to the capillary phenomenon, and thus the coarse surface is rough. It is preferable that the structured felt surface be in contact with the microporous membrane. The arrangement state is not particularly limited when the felt surface having a dense structure has a larger fiber diameter and a smaller fiber density than the fiber sheet forming the oil retaining layer.

The thickness of the felt thus obtained is preferably 1 mm or less. If it exceeds 1 mm, the felt becomes a heat insulating layer, and even if it comes into contact with the object to be coated, the viscosity of the oil does not decrease so much and it becomes difficult to apply the oil itself.

The oil applying member of the present invention is shown in FIGS.
As shown in FIG. 3, it may be roll-shaped or blade-shaped. In the case of the former roll shape, it may rotate in the same direction as the coated object or may rotate in the opposite direction.

Examples of the present invention will be described below, but the invention is not limited to the following examples.

[0026]

【Example】

(Example 1) As shown in FIGS. 5A and 5B, the main polyester component 12 (specific gravity: 1.38, 70% by weight)
Is divided into eight wedges and extends radially from the axis of the fiber into an American shape, and after division, it becomes one cross shape and four one-sided polyamide component 13 (specific gravity 1.14,
30% by weight), 13-dividable fiber with a chrysanthemum-shaped cross section (fineness: 2 denier, fiber length: 38 mm) was carded into a fiber web, which was then entangled at the same time with a water pressure of 95 kg / cm ^2. Then, a non-woven fabric having a basis weight of 85 g / m ² and a thickness of 0.4 mm was obtained. The fiber diameter of this non-woven fabric is a value measured based on an electron micrograph. The wedge-shaped polyester component 12 has an average of 7.2 μm and the cross-shaped polyamide component has an average of 13.
The single-sided polyamide component had a size of 9 μm and had a size of 7.8 μm. Moreover, the cross-sectional area of the polyester component 12 is 1.8 × 1.
0 is ^-7 cm ^2, the cross-sectional area of 4.3 × 10 ^-7 cm ² of the polyamide component of the cross-shaped, cross-sectional area of the polyamide component of one character shape is met 1.0 × 10 ^-7 cm ² It was From this measurement result, the fiber density was 9,400 m / cm ³ .

The nonwoven fabric having a width of 310 mm has a viscosity of 1
After impregnating with dimethyl silicone oil of 0000CS, the shaft 6 with a diameter of 6 mm and a length of 330 mm is attached with an outer diameter of 20.
The oil holding layer 7 was formed by flatly winding the film to a thickness of mm.

Then, the surface of the oil retaining layer is partially coated with a room temperature curing type silicone resin, and the pore size is 0.5 μm.
m, porosity 40%, film thickness 0.1mm made of polytetrafluoroethylene microporous membrane (trade name tape seal made by Nippon Bulker Kogyo Co., Ltd.) 1 round flat winding oil containing 50g of dimethyl silicone oil A coating roll was obtained.

(Embodiment 2) The cross section of Embodiment 1 is a chrysanthemum type 1
50 g of dimethyl silicone oil was prepared in the same manner as in Example 1 except that 60% by weight of tri-dividable fiber and 40% by weight of ordinary polyester fiber (fiber diameter 12.4 μm, specific gravity 1.38) were used. Thus, an oil coating roll was obtained. The non-woven fabric forming this oil retaining layer had a basis weight of 85 g / m ² , a thickness of 0.5 mm, and a fiber density of 4,900 m / c.
It was m ³ .

(Example 3) A fiber-forming polypropylene resin melt (specific gravity 0.9) was introduced into a nozzle orifice,
The fibers were spun out from the orifice and subjected to high-speed hot air, and then collected on a screen support to obtain a nonwoven fabric having an average fiber diameter of 2 μm, a basis weight of 80 g / m ² , and a thickness of 0.4 mm. The fiber density of this non-woven fabric was 71,700 m / cm ³ .

Then, this non-woven fabric was flat-wound on the shaft 6 in the same manner as in Example 1, vacuum-impregnated with dimethyl silicone oil having a viscosity of 300CS, and then wound with a polytetrafluoroethylene microporous membrane to obtain dimethyl silicone. An oil coating roll containing 35 g of oil was obtained.

Example 4 Meta-type aromatic polyamide fiber (fiber diameter 14.0 μm, fiber length 38 mm, specific gravity 1.44) 6
0% by weight and unstretched polyester fiber (fiber diameter 22.
6, a fiber length of 38 mm, a specific gravity of 1.38) and 40% by weight were mixed and carded into a fiber web, and then the temperature was set to 217.
It is passed between calender rolls under the conditions of ℃ and linear pressure of 90 kg / cm, and fused and fixed with unstretched polyester.
A felt having a thickness of 6 g / m ² , a thickness of 65 μm and a fiber density of 4,000 m / cm ³ was obtained. The felt was flat-wound on the oil coating roll obtained in the same manner as in Example 1 until the outer diameter was 22 mm, to obtain an oil coating roll having the elastic layer 9.

Example 5 Meta-type aromatic polyamide fiber (fiber diameter 22.2 μm, fiber length 38 mm, specific gravity 1.44) 1
A fiber web having a basis weight of 40 g / m ² consisting of 00% by weight, and a meta-aromatic polyamide fiber (fiber diameter 9.9 μm, fiber length 38
mm, specific gravity 1.44) 100 wt% basis weight 20 g / m ²
And a fiber web of No. 1 were laminated and entangled with a water flow having a water pressure of 90 kg / cm ² to obtain a felt having a basis weight of 60 g / m ² and a thickness of 0.3 mm. The fiber density of one side of this felt (the side using the meta-aromatic polyamide fiber with a fiber diameter of 22.2 μm) is 24.
The fiber density was 0 m / cm ³ and the fiber density on the other surface was 600 m / cm ³ . The surface of the felt having a fiber density of 240 m / cm ³ was flat-wound to an outer diameter of 22 mm so that the surface of the felt was in contact with the microporous film of the oil coating roll obtained in the same manner as in Example 1, and the elastic layer 9 An oil coating roll having

(Example 6) The warp yarn is polyester fiber (single yarn 8 denier, 100 multifilaments)
And the weft is made of highly shrinkable polyester fiber (single yarn 8 denier, 200 multifilaments), outer diameter 2
After coating the oil-coated roll surface obtained in the same manner as in Example 1 with a 3 mm heat-shrinkable sleeve, the heat-shrinkable sleeve is shrunk and adhered by hot air at 150 ° C. to have the elastic layer 9. An oil-coated roll having a diameter of 21 mm was obtained.

Comparative Example 1 Meta-type aromatic polyamide fiber (manufactured by DuPont, trade name Nomex, specific gravity 1.44,
50 g of dimethyl silicone oil was prepared in the same manner as in Example 1 except that a fiber diameter of 12 μm and a fiber length of 38 mm) were used.
An oil-coated roll containing it was obtained. This non-woven fabric has a basis weight of 85 g / m ² , a thickness of 0.5 mm, and a fiber density of 980 m / c.
It was m ³ .

(Comparative Example 2) An oil-coated roll was prepared by winding the polytetrafluoroethylene microporous membrane of Comparative Example 1 on it.

(Comparative Example 3) An oil-coated roll was prepared in exactly the same manner as in Example 1 and was not wrapped with a polytetrafluoroethylene microporous membrane.

Comparative Example 4 Meta-aromatic polyamide fiber (manufactured by DuPont, trade name Nomex, specific gravity 1.44,
A fiber web having a fiber diameter of 12 μm and a fiber length of 38 mm) was carded and entangled with a needle having a needle density of 300 needles / cm ² to obtain a nonwoven fabric having a basis weight of 450 g / m ² and a thickness of 2 mm.
This non-woven fabric having a width of 30 mm was provided with 15 through holes 11 having a diameter of 1 mm at the positions shown in FIG.
After wrapping spirally around an aluminum hollow pipe with an outer diameter of 25 mm, a wall thickness of 1 mm and a length of 300 mm, 45 g of dimethyl silicone oil with a viscosity of 10,000 CS is wrapped around the hollow pipe.
After injection, the injection port was sealed with a room temperature curing type silicone rubber to obtain an oil-coated roll.

(Oil transfer amount test) The oil application rolls of Examples 1 to 6 and Comparative Examples 1 to 4 are respectively brought into contact with a 120 ° C. roll which rotates at 10 m / min to be rotated. Then, the oil transfer amount was determined from the weight change of the oil application roll every hour. The results are shown in Table 1, FIG. 6 and FIG.
As shown in FIG. 5, the average oil application amount of the oil application rolls of Examples 1 to 6 was 0.025 g / hour and 0.05.
6 g / hour, 0.051 g / hour, 0.041 g / hour, 0.0
It can be seen that it is stable at 050 g / hour and 0.081 g / hour, and that the minimum required amount of oil or more is applied. The minimum required oil application amount is about 0.01 g / hour.

[0040]

[Table 1]

(Long-term storage test) The oil-coated rolls of Examples 1 to 6 and Comparative Examples 1 to 4 were left at room temperature, and it was determined whether or not oil exuded after 6 months and 1 year. The results are shown in Table 2.

[0042]

[Table 2]

[0043]

The oil application member of the present invention has a fiber diameter of 1
Since it has an oil retaining layer made of a fiber sheet containing fibers of 0 μm or less and has a good oil retaining property, the amount of application to the object to be coated can be made appropriate. Further, since the microporous membrane layer is provided outside the oil retaining layer, even if the amount of oil released from the oil retaining layer increases, the coating amount can be controlled by the microporous membrane layer, so the coating amount changes. It is an oil application member that is difficult to do.

If an elastic layer is provided outside the microporous membrane layer, the oil can be retained, so that there is no problem that the oil seeps out and stains the surroundings, or the hands are soiled when the oil application member is installed. . In addition, since the microporous film does not directly contact the object to be coated, the microporous film is protected from damage and the toner does not block the micropores of the microporous film. It can be performed stably and can be used for a longer period of time. Furthermore, since the elastic layer can act as a heat insulating layer, it is possible to use a fiber sheet having poor heat resistance as an oil retaining layer.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a usage state of an oil applying member.

2A is a cross-sectional view of an example of an oil applying member, FIG. 2B is a cross-sectional view of another example of an oil applying member, and FIG. 2C is a cross-sectional view of another example of an oil applying member.

3A is a cross-sectional view of another example of the oil applying member, FIG. 3B is a cross-sectional view of another example of the oil applying member, and FIG. 3C is a cross-sectional view of another example of the oil applying member.

FIG. 4 is a development view showing the positions of through holes of a hollow pipe in Comparative Example 4.

5A is a cross-sectional view of the splittable fiber, and FIG. 5B is a schematic cross-sectional view of the splittable fiber after splitting.

FIG. 6 is a graph showing the relationship between the oil transfer amount and the elapsed time.

FIG. 7 is a graph showing the relationship between the oil transfer amount and the elapsed time.

[Explanation of symbols]

 1 Fixing Roll 2 Pressure Roll 3 Oil Applying Member 4 Toner 5 Paper 6 Shaft 7 Oil Retaining Layer 8 Microporous Membrane Layer 9 Elastic Body Layer 10 Hollow Pipe Development 11 Through Hole 12 Polyester Component 13 Polyamide Component

Claims (2)

[Claims] 1. An oil application member having a microporous membrane layer on the outside of an oil holding layer made of a fiber sheet containing fibers having a fiber diameter of 10 μm or less. 2. The oil application member according to claim 1, further comprising an elastic body layer outside the microporous membrane layer.