JP2009300700A - Oil application roll - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil application roll able to ensure uniform application of oil for a long term. <P>SOLUTION: A polytetrafluoroethylene (PTFE) porus sheet 14 is wound and bonded, via a silicone adhesive 13, around an oil holding-and-regulating member 12, which holds silicone oil and regulates the amount of silicone oil that is applied. Thus, the oil application roll is formed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an oil application roll which is a component part of a fixing device used in an electrophotographic printer, a copying machine or the like.

  Some fixing devices in electrophotographic printers, copying machines, and the like use an oil application roll that applies a small amount of release oil such as silicone oil to the fixing roll. Various types of such oil application rolls have been proposed.

  Such an oil application roll has a function of applying an appropriate amount of release oil for a certain period of time. For example, an oil holder is provided on a roll base and a heat-shrinkable porous fluororesin is provided as an oil control layer on the surface layer. There is an oil application roll that is attached with a cylindrical film and is heat-shrinked to adhere the cylindrical film (see Patent Document 1, etc.). In addition, there is an oil application device in which an oil application amount control layer is bonded to an oil holding member with a mixture of an adhesive and silicone oil (see Patent Document 2 and the like).

  In such an oil application roll, there is a demand in recent years that a very small amount of oil can be applied uniformly over a very long period of time. However, in the conventional design philosophy in which the oil application amount control layer is provided on the outer periphery, it has been difficult to sufficiently respond. That is, since the oil application amount control layer as in Patent Document 1 is heat-shrinked so that the tubular film of the porous fluororesin is brought into close contact, the heat shrinkage of the tubular film proceeds with long-term use. There is a problem that the hole diameter becomes small and the oil application amount changes, or the tubular film shrinks in the axial direction and the end of the tubular film floats. Long-term use was difficult.

  Further, in the type in which the oil application amount control layer is bonded with a mixture of an adhesive and silicone oil as in Patent Document 2, it is necessary to properly provide an oil passage for the oil in the adhesive layer, and the design is difficult.

  On the other hand, the present applicant has previously proposed an oil application roll manufactured using an oil-containing sheet, an oil-permeable sheet, and an oil-permeation-suppressing sheet, which are nonwoven fabrics (see Patent Documents 3 and 4).

  However, such an oil application roll is a type that is exchanged in a short period of time, and when used over a long period of time, the amount of application decreases due to toner adhesion, and is not suitable for long-term use.

Japanese Patent Laid-Open No. 9-185282 JP 2000-310920 A JP-A-6-346915 JP-A-6-348166

  This invention makes it a subject to provide the oil application roll which can apply | coat oil over a long period of time in view of such a situation.

  According to a first aspect of the present invention for solving the above-described problem, a polytetrafluoroethylene (PTFE) porous sheet is wound around an oil retention regulating member that retains silicone oil and regulates the coating amount via a silicone adhesive. The oil application roll is characterized in that it is formed by rotating and bonding.

  A second aspect of the present invention is the oil application roll according to the first aspect, wherein the PTFE porous sheet has a porosity of 45 to 80%.

  According to a third aspect of the present invention, in the oil application roll according to the first or second aspect, the PTFE porous sheet has a thickness of 50 to 150 μm.

  According to a fourth aspect of the present invention, in the oil coating roll according to any one of the first to third aspects, the PTFE porous sheet is composed of a porous film having an average pore diameter of 0.05 to 1 μm. On the oil application roll.

  According to a fifth aspect of the present invention, in the oil application roll according to any one of the first to fourth aspects, the silicone-based adhesive is a predetermined pattern in which an application area ratio is 20 to 60% on the PTFE porous sheet. The oil coating roll is characterized in that it is applied in the above.

  According to a sixth aspect of the present invention, in the oil application roll according to the fifth aspect, the predetermined pattern has a uniform application area of the adhesive over the circumferential direction of the silicone adhesive in the axial direction. The oil coating roll is characterized by having a pattern.

  According to a seventh aspect of the present invention, in the oil application roll according to any one of the first to sixth aspects, the silicone adhesive is a thermosetting one-part silicone rubber adhesive. It is in the coating roll.

  According to an eighth aspect of the present invention, in the oil application roll according to any one of the first to seventh aspects, the oil retention regulating member winds the oil-impregnated sheet and the oil permeation-suppressing sheet and The oil coating roll is characterized in that the surface is made of the oil permeation inhibiting sheet.

  According to a ninth aspect of the present invention, in the oil application roll according to any one of the first to seventh aspects, the oil retention regulating member includes an oil impregnated sheet, an oil permeable sheet, and an oil permeation suppression sheet. The oil application roll is characterized in that it is wound and at least the outermost surface is made of the oil permeation suppressing sheet.

  Hereinafter, the present invention will be described in detail with reference to an oil application roll according to an embodiment of the present invention.

  FIG. 1 shows a cross-sectional view of the oil application roll of the present invention. As shown in FIG. 1, the oil application roll 10 is obtained by winding a PTFE porous sheet 14 around an oil retention regulating member 12 provided on a core body 11 with an adhesive 13 therebetween.

  In the oil application roll 10, the outermost PTFE porous sheet 14 does not function as an oil permeation control layer as in the prior art, and the oil retention regulating member 12 functions as an oil permeation control layer. Details will be described later.

  Here, the core body 11 is not particularly limited, whether it is made of metal or resin.

  The oil retention regulating member 12 is provided on the core body 11, and stores and holds the silicone oil as the release oil, that is, does not discharge the stored silicone oil as it is and retains it with a predetermined retention force. However, the configuration is not particularly limited, but preferably an oil-impregnated sheet made of a non-woven fabric having oil-impregnating property or an oil-permeable material made of a non-woven fabric having oil permeation inhibiting property. A configuration using an oil-permeable sheet together with an inhibitory sheet, and further an oil-impregnated sheet can be exemplified. That is, the configuration of the oil retention regulating member 12 is, for example, an oil-impregnated sheet alone, or an oil-impregnated sheet and an oil-permeable sheet wound and then an oil permeation-suppressing sheet wrapped around the outermost layer, or an oil Examples of impregnating sheets and oil permeation suppression sheets, or oil impregnation sheets, oil permeation sheets and oil permeation suppression sheets laminated and wound so that the oil permeation suppression sheets are on the outside, etc. be able to.

  As such an oil impregnated sheet, an oil permeation suppressing sheet, and an oil permeable sheet, those described in Patent Documents 3 and 4 described above can be used. The oil-impregnated sheet can be used without particular limitation as long as it is a porous oil-impregnated sheet having an appropriate oil retaining property, for example, a nonwoven fabric formed from fibers having heat resistance and oil resistance, and oil absorption. Can be preferably used. The oil-permeable sheet can be a non-woven sheet formed from synthetic resin fibers having heat resistance and oil resistance, for example, and does not suppress leaching of the release oil and has an appropriate strength. Any porous sheet having durability can be used without particular limitation. The oil permeation suppression sheet is for adjusting so that a predetermined oil leaching rate (coating amount) can be obtained. For example, the oil permeation suppression sheet is a relatively oil permeable sheet formed from synthetic resin fibers having heat resistance and oil resistance. A small nonwoven sheet or the like can be appropriately selected and used.

  A PTFE porous sheet 14 is wound around and adhered to the outside of the oil retention regulating member 12 with an adhesive 13 interposed therebetween.

  Here, the PTFE porous sheet 14 does not substantially function as an oil permeation control layer as in the prior art, but functions as an oil permeable release layer. That is, the oil permeability is not adjusted, and the toner having a low adhesion property is used. The PTFE porous sheet 14 is bonded to the surface of an oil retention regulating member 12 wound with a PTFE sheet and impregnated with silicone oil via an adhesive 13. Although the PTFE porous sheet 14 does not substantially function as an oil permeation control layer, it functions as an oil permeation control layer by adjusting the porosity, average pore diameter, oil viscosity, etc. of the PTFE porous sheet 14. In such a case, the above-described oil permeation suppressing sheet can be omitted.

  Such a PTFE porous sheet 14 has a porosity of 45 to 80%, preferably a porosity of 55 to 65%. That is, it is important that the porosity is small in order that the adhesion of the toner due to use is small and a constant coating amount can be maintained stably over a long period of time, while the porosity is important. It has been found that adhesion is greatly affected by adhesion, and adhesion is difficult when the porosity is too small, and a porosity of 45 to 80%, preferably a porosity of 55 to 65% is desirable. It was found that if the porosity was less than 45%, there was a problem in terms of adhesiveness, whereas if the porosity was greater than 80%, it was inferior in terms of releasability.

  Moreover, it is preferable that this PTFE porous sheet has a thickness of 50 to 150 μm. If it is thicker than this, a step at the winding end becomes a problem, and if it is thinner than this, there is a problem in strength.

  The PTFE porous sheet 14 is desirably formed of a porous film having an average pore diameter of 0.05 to 1 μm, preferably 0.1 to 1 μm. If the average pore diameter is smaller than this, the adhesive 13 hardly penetrates into the pores, and sufficient adhesiveness cannot be ensured. On the other hand, if the average pore diameter is larger than this, the toner tends to penetrate, which is not preferable.

  As the adhesive 13 for adhering the PTFE porous sheet 14, a silicone-based adhesive, in particular, a silicone-based adhesive having a high affinity with the silicone oil impregnated in the oil retention regulating member 12 is used. Such a silicone-based adhesive is based on the knowledge that since the silicone oil permeates, the oil applicability is not completely suppressed and the adhesive strength of the silicone oil is not reduced.

  Therefore, the adhesive 13 may be applied over the entire surface, but is preferably applied in a predetermined pattern. That is, it is preferable to apply through a mask (screen) having a predetermined transmission pattern. The transmission area ratio of the mask, that is, the application area ratio of the adhesive is 20 to 60%, preferably 30 to 50%. If this is smaller than this, it is difficult to obtain a sufficient adhesive force, and if it is larger than this, it is difficult to ensure a sufficient coating amount.

  Further, the transmission pattern of the mask is preferably a pattern in which the coating area in the circumferential direction of the applied adhesive 13 is uniform in the axial direction. That is, when the oil application roll 10 is used, the oil application is prevented from becoming non-uniform over the axial direction.

  FIG. 2 shows an application pattern in which the adhesive 13 is applied to the PTFE porous sheet 14 before being wound. The dot-like adhesive pattern 13a is provided in a staggered pattern, and the application area accumulated in the circumferential direction is the axis. It is designed to be uniform everywhere in the direction.

  Moreover, it is preferable that the application | coating thickness of the adhesive agent 13 is 100-200 micrometers in the apply | coated state. If it is thinner than this, it is difficult to enter the pores of the PTFE porous sheet 14 to ensure the adhesive force. On the other hand, if it is thicker than this, it may come out to the surface of the PTFE porous sheet 14, It is not preferable.

  Such application thickness depends on the thickness of the mask in the application using the above-described mask. Therefore, the application thickness can be adjusted by adjusting the thickness of the mask.

  In addition, the method of apply | coating the adhesive agent 13 with such an application pattern is not limited to the application | coating using a mask, It can perform by various printings, such as screen printing.

  In addition, as described above, the silicone-based adhesive is not particularly limited, and a two-pack type adhesive can also be used. However, in order to perform mask coating and the like, it is a thermosetting one-pack silicone rubber adhesive. Is preferred.

  An adhesive auxiliary layer may be provided so that the adhesiveness between the oil retention regulating member 12 and the adhesive 13 or the adhesiveness between the adhesive 13 and the PTFE porous sheet 14 is insufficient or further improved. Such an adhesive auxiliary layer has no influence on the oil application performance, that is, a layer having good oil permeability and good adhesiveness with the silicone-based adhesive, and the outer peripheral surface of the oil retention regulating member 12 or the PTFE porous layer. It can be provided on the inner peripheral surface of the quality sheet 14.

  The oil application roll of the present invention described above is formed by winding a PTFE porous sheet and adhering it to an oil holding regulation member that holds silicone oil and regulates the application amount via a silicone adhesive, Oil can be applied uniformly over a long period of time.

  Here, the oil application amount generally required as an oil application roll is 0.05 mg / A4 to 0.5 mg / A4, but the configuration of the oil holding member and the porosity of the porous sheet are changed. By combining them, an oil application roll having a desired oil application amount within the range of the oil application amount described above can be freely designed.

  Hereinafter, the present invention will be described in more detail based on examples.

(Test Example 1)
Silicone oils having different viscosities were dropped on a PTFE porous sheet having different porosity as shown in Table 1 below with a dropper, and the time until the oil passed through the PTFE porous sheet was measured. The results are also shown in Table 1.

  As a result, it was found that the target oil application amount can be designed only by changing the porosity of the PTFE porous sheet.

(Example 1)
A rock wool paper having a thickness of 0.22 mm and a width of 300 mm as an oil-impregnated sheet is wound many times on a core body made of a cylindrical steel core bar having a diameter of 10 mm and a length of 330 mm, to a diameter of 17 mm. After wrapping the aramid fiber paper (trade name: Nomex paper, T-411, manufactured by DuPont Japan Co., Ltd.) having a thickness of 0.13 mm and a width of 300 mm as an oil permeation inhibiting sheet, the end is fixed with a double-sided tape. Further, an oil retention regulating member having an outer diameter of 19 mm was formed by impregnating silicone oil having a viscosity of 1000 CS.

  A PTFE porous sheet having a porous pore diameter of 0.10 μm, a thickness of 80 μm, and a porosity of 77% was wound on this and bonded with a thermosetting one-pack silicone rubber adhesive to obtain an oil application roll of Example 1. The adhesive application pattern was as shown in FIG. 2, and the adhesive application area ratio was 40%.

(Example 2)
An oil application roll of Example 2 was obtained in the same manner as Example 1 except that it was impregnated with 3000 CS silicone oil instead of 1000 CS silicone oil.

(Example 3)
Oil core with a diameter of 10 mm and a length of 330 mm is wound on a core made of a cylindrical steel core with a number of oil wool-impregnated sheets, 0.22 mm in thickness and 300 mm in width. After forming the regulating member, an oil retention regulating member having an outer diameter of 19 mm was formed by impregnating silicone oil having a viscosity of 1000 CS.

  A PTFE porous sheet having a porous pore diameter of 0.15 μm, a thickness of 90 μm, and a porosity of 60% was wound thereon, and adhered with a thermosetting one-pack silicone rubber adhesive to obtain an oil application roll of Example 3. The adhesive application pattern was as shown in FIG. 2, and the adhesive application area ratio was 40%.

(Example 4)
An oil application roll of Example 4 was obtained in the same manner as in Example 3 except that 3000 CS silicone oil was impregnated instead of 1000 CS silicone oil.

(Test Example 2)
The oil application rolls of Examples 1 to 4 were used as the oil application rolls, pressed against the pressure roll of Sharp Copier SF-2540 with a load of 500 g on one side, and passed through A4 size paper at 2000 sheets / day. Then, a paper passing test was conducted up to 10,000 sheets, and the oil application amount of the oil application roll was measured. The oil application amount was calculated by taking out an oil application roll every 2000 sheets passed and calculating the oil application amount per A4 size paper from the weight reduction amount. The results are shown in Table 2 below and FIG.

  As a result, it was found that the oil application rolls of the respective examples had different oil application amounts, whereby an oil application roll having a target oil application amount could be manufactured. In addition, it was found that the change in the amount of oil applied until 10,000 sheets passed through the oil application roll of each example was sufficiently practical.

  In addition, the oil application rolls of Examples 1 to 4 have good adhesion between the oil holding member and the PTFE porous sheet without passing through the PTFE porous sheet and peeling off the winding end after passing 10,000 sheets. It was confirmed.

It is sectional drawing which shows an example of the oil application roll of this invention. It is a figure which shows an example of the application pattern of an adhesive agent. 10 is a graph showing the results of Test Example 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Oil application roll 11 Core 12 Oil holding | maintenance regulating member 13 Adhesive 14 PTFE porous sheet

Claims (9)

An oil application roll characterized in that a polytetrafluoroethylene (PTFE) porous sheet is wound around and bonded to an oil retention regulating member that holds silicone oil and regulates the amount of application via a silicone adhesive. . 2. The oil application roll according to claim 1, wherein the PTFE porous sheet has a porosity of 45 to 80%. The oil application roll according to claim 1 or 2, wherein the porous PTFE sheet has a thickness of 50 to 150 µm. The oil application roll according to any one of claims 1 to 3, wherein the PTFE porous sheet is made of a porous film having an average pore diameter of 0.05 to 1 µm. The oil application roll according to any one of claims 1 to 4, wherein the silicone adhesive is applied to the PTFE porous sheet in a predetermined pattern with an application area ratio of 20 to 60%. An oil application roll characterized by 6. The oil application roll according to claim 5, wherein the predetermined pattern is a pattern in which an application area of the adhesive across the circumferential direction of the silicone adhesive is uniform in the axial direction. Application roll. The oil application roll according to any one of claims 1 to 6, wherein the silicone-based adhesive is a thermosetting one-pack silicone rubber adhesive. The oil application roll according to any one of claims 1 to 7, wherein the oil retention regulating member winds an oil-impregnated sheet and an oil permeation suppression sheet, and at least the outermost surface is the oil permeation suppression sheet. An oil application roll characterized by comprising: The oil application roll according to any one of claims 1 to 7, wherein the oil retention regulating member winds an oil-impregnated sheet, an oil-permeable sheet, and an oil-permeation-suppressing sheet, and at least the outermost surface is the surface. An oil application roll comprising an oil permeation suppression sheet.

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