JP2005266004A - Ventilation filter for toner container, ventilation member, toner container using them and ventilation filter assembly for the toner container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ventilation filter for a toner container whose service life is prolonged, and to provide a toner container which uses the same. <P>SOLUTION: The ventilation filter for the toner container 1 includes a PTFE porous film 2 and a permeable support layer 3, and the scavenging efficiency of the support layer 3 measured by using air dust whose particle size is 1 to 5 μm is set to ≥60%. In the toner container, the filter 1 is attached to the ventilation part of the container having space for storing toner. For example, nonwoven fabric is used for the support layer 3. It is desirable that the nonwoven fabric is electret-treated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner container ventilation filter, a ventilation member, a toner container using them, and a toner container ventilation filter assembly.

  Image forming apparatuses such as laser printers, copiers, facsimiles, and composite devices that combine these form images in the following manner. First, the surface of the photosensitive drum is charged and a laser beam is irradiated on the surface to form a latent image. Thereafter, the latent image is developed by attaching toner in a developing device disposed around the photosensitive drum to the photosensitive drum. The image formed on the photosensitive drum in this manner is transferred to an intermediate transfer member or directly to a recording medium such as paper.

  As a method for replenishing toner, a method for replacing the entire developing device containing toner, or a method for replacing the toner box in which the developing device includes another component of the developing device and a separable toner box. There is.

  In a developing device used for a method of replacing the entire developing device, toner is generally contained in the same container (within the developing device) together with a stirring bar, a toner supply roll, and the like. A vent is provided to prevent the internal pressure of the container from increasing with the rotation of the stirring bar and the toner supply roller, and a filter is attached to the vent so that the toner does not leak together with the air. For this filter, a laminate comprising a polytetrafluoroethylene (hereinafter referred to as “PTFE”) porous film and a woven or non-woven fabric is used. The filter reinforces a thin, relatively low strength PTFE porous membrane by laminating a woven or non-woven fabric on the PTFE porous membrane, and facilitates attachment to a container by thermal welding or adhesion ( For example, see Patent Document 1).

  The toner box is also provided with a ventilation portion to which a filter is attached, and it is possible to suppress negative pressure from being applied to the toner box as the amount of toner decreases.

  By the way, the untransferred toner remaining on the photosensitive drum of the image forming apparatus is removed from the photosensitive drum by a cleaning device in the image forming apparatus, and is sent to and stored in a collection container by a waste toner conveying device. The collection container is provided with a ventilation portion for discharging the air sucked together with the toner out of the container. A filter including a PTFE porous film is attached to the ventilation portion so that toner does not leak together with air (see, for example, Patent Document 2).

As described above, a toner container such as a developing device, a toner box, and a toner collection container is used for the image forming apparatus, and a filter including a PTFE porous film is often used for the toner container.
Japanese Patent Laid-Open No. 9-311553 (page 8, FIG. 5) JP 2002-311711 (page 6, FIG. 7)

  However, the PTFE porous membrane used for such an application has a problem that clogging occurs due to long-term use and air permeability is lowered. In addition, when a pinhole is generated in the PTFE porous membrane due to repeated bending of the filter due to pressure fluctuation in the container, cracks are generated from the pinhole formed in the PTFE porous membrane due to further pressure fluctuation. There was also a risk of toner leakage.

  The air-permeable filter for a toner container of the present invention is an air-permeable filter for a toner container comprising a PTFE porous membrane and an air-permeable support layer, wherein the air-permeable support layer is measured using particles having a particle diameter of 1 μm to 5 μm. The collection efficiency is 60% or more.

  The toner container ventilation filter assembly of the present invention includes a plurality of toner container ventilation filters of the present invention, and the plurality of toner container ventilation filters are detachably attached to a sheet-like material. .

  The ventilation member of the present invention includes the toner container ventilation filter of the present invention and a support having a through hole, and the toner container ventilation filter is attached to the support so as to cover the through hole. It is characterized by.

  The toner container of the present invention is characterized in that the toner container ventilation filter of the present invention is attached to a ventilation portion of a container having a space for containing toner.

  Another toner container of the present invention is characterized in that the ventilation member of the present invention is attached to a ventilation portion of a container having a space for containing toner.

  According to the present invention, it is possible to provide a toner container ventilation filter having a long life and a toner container using the same.

  An example of a toner container ventilation filter, a ventilation member, a toner container using them, and a toner container ventilation filter assembly according to the present invention will be described with reference to the drawings.

(Embodiment 1)
As shown in FIG. 1, the toner container ventilation filter 1 of the present embodiment includes a PTFE porous membrane 2 and a breathable support layer 3, and the trapping efficiency of the breathable support layer 3 is 60% or more. Therefore, even if a pinhole is formed in the PTFE porous film 2, most of the toner can be captured by the air-permeable support layer 3, and the toner leakage from the toner container air-permeable filter 1 can be suppressed. As described above, in the toner container filter 1 of the present embodiment, even if a pinhole is formed in the PTFE porous film 2, the filter function is not immediately lost by the formation of the pinhole, and a long life can be realized. .

  In addition, although there is no restriction | limiting in particular about the upper limit of the collection efficiency of the air permeable support layer 3, Usually, it is 95% or less. In the present invention, the collection efficiency is a value measured by the following method.

The toner container ventilation filter 1 is set in a circular holder so that the effective area is 100 cm ² . A pressure difference is applied between the inlet side and the outlet side of the air, and air containing particles (atmospheric dust) having a particle diameter of 1 μm to 5 μm is supplied to the inlet side in a state where the air permeation flow rate is 5.3 cm / sec. The particle concentration on the inlet side (number of particles / liter) and the concentration of particles on the outlet side through the sample (particle number / liter) are measured with a particle counter, and these are substituted into Equation 1 below for calculation.

(Equation 1)
Collection efficiency (%) = (1 outlet side particle concentration / inlet side particle concentration) × 100

  Although there is no restriction | limiting in particular about the average hole diameter of the PTFE porous membrane 2, Usually, 10 micrometers or less, Furthermore, it is preferable that they are 0.5 micrometer-6 micrometers. If it is too large, the strength will be insufficient and toner leakage will easily occur. If it is too small, sufficient air permeability cannot be secured.

  Although there is no restriction | limiting in particular about the thickness of the PTFE porous membrane 2, Usually, 2 micrometers or more are preferable. This is because if the thickness is too thin, the toner container may be damaged due to an increase in pressure. Although there is no restriction | limiting in particular about the upper limit of the thickness of the PTFE porous membrane 2, Usually, it is preferable that it is 2000 micrometers or less in order that pressure loss may not become large too much.

The PTFE porous membrane 2 preferably has an air permeability (fragile air permeability) measured in accordance with JIS L 1096 of 0.1 to 50 cm ³ · cm ⁻² · s ⁻¹ . This is because the pressure difference inside and outside the toner container can be quickly eliminated.

  In the example shown in FIG. 1, the toner container ventilation filter 1 includes one layer of PTFE porous membrane 2 and one layer of air permeable support layer 3, but the toner container ventilation filter of the present embodiment is The present invention is not limited to this configuration, and a plurality of porous PTFE membranes 2 and a plurality of breathable support layers 3 may be included, and the PTFE porous membranes 2 and the breathable support layers 3 may be alternately stacked. Moreover, either or both of the PTFE porous membrane 2 and the air-permeable support layer 3 may be included in a continuous layer. The plurality of breathable support layers 3 may include the breathable support layers 3 made of different materials.

  The PTFE porous membrane 2 can be produced by a conventionally known method. An example of the manufacturing method will be described below. First, a paste-like mixture obtained by adding a liquid lubricant to PTFE fine powder is preformed. The liquid lubricant is not particularly limited as long as it can wet the surface of the PTFE fine powder and can be removed by extraction or heating. For example, hydrocarbons such as naphtha and white oil can be used. The addition amount of the liquid lubricant is suitably about 5 to 50 parts by weight with respect to 100 parts by weight of PTFE fine powder. The above preforming is performed at a pressure that does not squeeze out the liquid lubricant.

  Next, the preformed body is extruded and / or rolled to form a sheet, and the sheet-like formed body thus obtained is stretched at least in a uniaxial direction to obtain a PTFE porous membrane. The stretching may be performed after removing the liquid lubricant. Stretching conditions can be set as appropriate. Usually, the temperature is 30 to 320 ° C., and the stretching ratio is 2 to 30 times in both the longitudinal and transverse directions. Further, if the PTFE porous membrane is heated to the melting point of PTFE or higher and fired after stretching, the strength can be increased.

  The air-permeable support layer 3 is not particularly limited as long as the collection efficiency is 60% or more, but there are no particular restrictions on the material, form, etc. For example, porous materials such as nonwoven fabrics, sponges, foams, and ultrahigh molecular weight polyethylene porous bodies Can be used. In particular, a nonwoven fabric having a good balance between collection efficiency and air permeability is preferable. Examples of non-woven fiber materials include polyolefin (polypropylene (PP), polyethylene (PE), etc.), polyester, nylon 6, polyphenylene sulfide, polyamide (PA), acrylic resin, polysulfone, polyamideimide, polyimide, polyvinylidene fluoride, Cellulose, viscose and the like can be used. When the PTFE porous membrane 2 and the breathable support layer 3 are bonded by a thermal laminating method, it is preferable that the breathable support layer 3 contains a thermoplastic resin because thermal lamination is facilitated.

  The breathable support layer 3 may be a non-woven fabric using a core-sheath fiber in which fibers made of the above materials are combined, or a non-woven fabric containing fibers made of the above materials and glass fibers or carbon fibers. Also good. A nonwoven fabric containing two or more kinds of fibers can be produced, for example, by a wet method.

If the weights of the two types of non-woven fabrics to be compared are the same, a non-woven fabric formed from finer fibers is preferable because of higher collection efficiency. Specifically, when the basis weight is 10 to 300 g / m ² , the fiber diameter is preferably 0.2 μm to 15 μm. If it is too thin, the mechanical strength of the nonwoven fabric is small and the workability is poor, and if it is too thick, the collection efficiency decreases.

  The breathable support layer 3 may be electret-treated. When the electret treatment is performed, the toner collection efficiency can be increased by electrostatic force. As a method of giving electric charge to the nonwoven fabric, a method of polarizing the nonwoven fabric with a direct current high voltage, a method of applying a direct current high voltage to the needle electrode to generate ions in the atmosphere and applying them to the nonwoven fabric, a pulse discharge in the atmosphere The method etc. which generate | occur | produce ion and apply this to a nonwoven fabric are employable.

As shown in FIG. 2, the toner container breathable filter 1 further includes a breathable reinforcing layer 5, and the breathability of the breathable reinforcing layer 3 is measured according to JIS L 1096. It is preferable that the air permeability measured in accordance with JIS L 1096 is higher. This is because the strength of the air filter 1 for the toner container can be increased without impairing the air permeability. For example, when the fragile air permeability of the air-permeable support layer 3 is 5 to 20 cm ³ · cm ⁻² · s ⁻¹ , the fragile air permeability of the air-permeable reinforcing layer 5 is 20 to 300 cm ³ · cm ⁻² · s ^{−. 1} is preferred.

  The breathable reinforcing layer 5 is not particularly limited with respect to the material, form, etc. For example, a porous material similar to the breathable support layer 3, a net, or the like can be used. In the case of a nonwoven fabric, the fiber diameter of the nonwoven fabric is suitably 1 μm to 30 μm.

  Although there is no restriction | limiting in particular about the preparation methods of a nonwoven fabric, It is preferable to employ | adopt the melt blown method which can produce a nonwoven fabric with a very fine fiber (fiber diameter is about several microns). When a nonwoven fabric is produced by the melt blown method, a thermoplastic resin such as PP, PE, polyester, nylon 6, polyphenylene sulfide can be used as a material.

  As a method for joining the PTFE porous membrane 2 and the air-permeable support layer 3, for example, a method such as adhesive laminating, thermal laminating, heat welding, ultrasonic welding, vibration welding, or adhesion using an adhesive can be used. . For example, when the PTFE porous membrane 2 and the breathable support layer 3 are bonded by thermal lamination, a part of the breathable support layer 3 is melted by heating, and the PTFE porous membrane 2 and the breathable support layer 3 are bonded. What is necessary is just to adhere. The PTFE porous membrane 2 and the air-permeable support layer 3 may be bonded with a fusing agent such as hot melt powder interposed. As shown in FIG. 1, the PTFE porous membrane 2 and the air permeable support layer 3 may be joined only at the peripheral edge 1a of the air filter 1 for the toner container.

  As shown in FIG. 2, when the toner container ventilation filter 1 includes the breathable reinforcing layer 5, the PTFE porous film 2 and the breathable reinforcing layer 5 are joined to each other, and the breathable reinforcing layer 5 and the breathable supporting layer 3 are combined. The bonding may be performed by a method similar to the method of bonding the PTFE porous membrane 2 and the air-permeable support layer 3.

  The toner container ventilation filter 1 is preferably subjected to a liquid repellency treatment such as a water repellency treatment or an oil repellency treatment depending on the properties of the toner container ventilation filter 1 or the properties of the toner. For example, when the toner is an oil-containing toner, the oil may permeate into the pores of the PTFE porous membrane and impair air permeability.

  The liquid repellent treatment can be performed by applying a substance having a small surface tension, curing it after drying. The liquid repellent is not particularly limited as long as a film having a surface tension lower than that of the PTFE porous membrane 2 can be formed, but a polymer having a perfluoroalkyl group in the side chain is preferable. Such polymers include, for example, “Florard” (manufactured by Sumitomo 3M), “Scotch guard” (manufactured by Sumitomo 3M), “Tex Guard” (manufactured by Daikin Industries), “Unidyne” (manufactured by Daikin Industries), “Asahi” “Guard” (manufactured by Asahi Glass) etc. (all trade names) may be used. The liquid repellent may be applied by impregnation, spraying, or the like. The application amount of the liquid repellent is preferably adjusted so that a sufficient liquid repellent effect is obtained and the air permeability of the toner container air filter 1 is not hindered. The liquid repellent treatment may be performed only on the surface disposed on the toner side when attached to the container, or may be performed on the entire toner container ventilation filter 1.

  The shape and size of the toner container ventilation filter 1 are not particularly limited. In the example shown in FIG. 1, the toner container ventilation filter 1 has a circular shape. However, the toner container ventilation filter 1 may have any shape as long as it can be disposed so as to cover the ventilation portion of the container having a space for accommodating toner. Good.

  The toner container ventilation filter 1 can be attached to the container by a method such as heat welding, ultrasonic welding, vibration welding, adhesion with an adhesive, for example, an adhesive, and the like. It is preferable to attach with an adhesive layer. As shown in FIG. 3, when the peripheral edge of one surface of the toner container ventilation filter 1 is formed of the adhesive layer 4, the toner container ventilation filter 1 can be easily attached to the container. For the adhesive layer 4, for example, a double-sided tape or the like can be used.

  The pressure-sensitive adhesive layer 4 can be formed using a pressure sensitive adhesive such as silicone, acrylic or rubber. As shown in FIG. 3, the pressure-sensitive adhesive layer 4 may be a single layer, but as shown in FIG. 4, a pressure-sensitive adhesive is applied to both surfaces of a substrate 4b, for example, a plastic film such as a nonwoven fabric or a polyethylene terephthalate (PTE) film. The double-sided PSA sheet provided with the layer 4a is preferably used as the PSA layer 4. This is because the strength of the toner container ventilation filter 1 can be increased, the handling property is improved, and the process of attaching the toner container to the container can be easily automated.

  As shown in FIGS. 3 and 4, the adhesive layer 4 is provided in contact with the PTFE porous membrane 2, but is not limited thereto, and may be provided in contact with the air-permeable support layer 3. However, since the adhesive layer 4 has better adhesion with the PTFE porous membrane 2 than with the air-permeable support layer 3, the adhesive layer 4 is provided in contact with the PTFE porous membrane 2 from the viewpoint of adhesion. It is preferable.

  As shown in FIG. 5, the toner container ventilation filter 1 is preferably attached to the sheet 6 so as to be peelable and stored or transported. The toner container ventilation filter 1 assembly in which a plurality of toner container ventilation filters 1 are detachably attached to the sheet-like material 6 is easy to handle, and automation when the toner container ventilation filter 1 is attached to the container. This is because it becomes easy.

  For example, when the toner container ventilation filter 1 includes the adhesive layer 4 (see FIGS. 3 and 4), as shown in FIGS. 5 (a) and 5 (b), a plurality of sheets are formed on the sheet-like material 6 with silicon coated on the surface. The toner container ventilation filter 1 is attached and stored. When the toner container ventilation filter 1 does not include an adhesive layer, as shown in FIG. 6, a plurality of toner container ventilation filters 1 are provided on a sheet-like material 6 coated with a low-adhesive adhesive 6a. Paste and store. Although the sheet-like material shown in FIG. 5 (a) is plate-like, it may be a belt-like material as shown in FIG. 7, and the sheet-like material 6 to which a plurality of toner container ventilation filters 1 are attached is a roll. It may be wound into a shape.

  8 to 10 show an example of a toner container to which the toner container ventilation filter 1 is attached. These toner containers have the same structure as a conventional general toner container except that the toner container ventilation filter 1 of the present embodiment is attached.

  The toner container (toner box) shown in FIGS. 8A and 8B has a substantially cylindrical outer shape, and includes a toner container ventilation filter 1 and a container 23 having a space for accommodating toner therein. It is out. The container 23 includes a ventilation part 23a covered with the toner container ventilation filter 1, a shutter member 25 capable of opening and closing an opening part (not shown) by sliding, and an inside of the container 23 to dispose toner. And a scraping member (not shown) for discharging toward the opening.

  The toner container (developing device) shown in FIGS. 9A and 9B has a developing roller 26 that supplies toner to the photosensitive drum of the image forming apparatus, and a space for containing the toner 20, and the developing roller 26 described above. And the toner container ventilation filter 1 that covers the ventilation portion 23a of the container 23. The container 23 includes a stirring bar 27 for stirring the toner and a shutter member 24 that can open and close an opening for exposing the developing roller 26.

  The toner container shown in FIG. 10 is a toner container for collecting waste toner, and includes a container 23 having a space for storing toner therein and a toner container ventilation filter 1. The container 23 includes a ventilation portion 23a covered with the toner container ventilation filter 1 and an injection port 28 to which a tube for introducing waste toner is connected. The untransferred toner remaining on the photosensitive drum of the image forming apparatus is removed from the photosensitive drum by a cleaning device in the image forming apparatus, and is sent to a toner container as shown in FIG.

  The toner container ventilation filter 1 may be attached to the container 23 with one of the surfaces of the toner container ventilation filter 1 facing the toner side. When at least a part of one surface is formed of the PTFE porous membrane 2, if the PTFE porous membrane 2 is attached toward the toner side, the toner releasability with respect to the toner container ventilation filter 1 is good, When at least a part of one surface is formed from the air-permeable support layer 3, if the air-permeable support layer 3 is attached toward the toner side, the air-permeable support layer 3 functions as a prefilter, and the PTFE porous material Clogging of the film can be suppressed.

  As shown in FIGS. 11A and 11B, the toner container ventilation filter 1 may be attached either inside or outside the container 23. The number of toner container ventilation filters 1 attached to the container 23 is not particularly limited, and a plurality of toner container ventilation filters 1 may be attached to the other surface or the same surface of the container. When a plurality of toner container ventilation filters 1 are attached, the toner container is designed such that at least one toner container ventilation filter 1 is not blocked by the toner regardless of the position of the toner container in which the toner is stored. It is preferable to determine the attachment position of the container ventilation filter 1.

  Further, as shown in FIG. 11C, the toner container ventilation filter 1 is preferably nonporous at the periphery. This is because toner leakage can be suppressed from the end face of the toner container ventilation filter 1 by making the peripheral edge of the toner container ventilation filter 1 non-porous by welding or the like.

(Embodiment 2)
In Embodiment 2, an example of the ventilation member of the present invention and a toner container using the ventilation member will be described.

  As shown in FIG. 12A, the ventilation member 11 of the present embodiment includes the toner container ventilation filter 1 shown in FIG. 3 and a support 10 having a through hole 12, and includes a toner container ventilation filter. 1 is attached to the support body 10 so as to cover the through hole 12. Since the toner container ventilation filter 1 is thin and light, it is not easy to handle by itself, and it is not easy to automate the attachment process to the container. When the toner container ventilation filter 1 is supported by the support 10, attachment to the container becomes easy, and the degree of freedom of attachment to the container increases. For example, as shown in FIG. 12B, the support 10 includes a cylindrical portion that can be inserted into the ventilation portion 23 a of the container 23, and the toner container ventilation filter 1 is inserted into the cylindrical portion. Since the toner container ventilation filter 1 is attached to the start side end, the toner container ventilation filter 1 can be arranged from the outside of the container 23 into the ventilation part 23 a or inside the container 23.

  The material of the support 10 may be any resin or metal, but is preferably a thermoplastic resin that can be easily molded. As the thermoplastic resin, for example, polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), ABS resin, polysulfone (PS), thermoplastic elastomer, polypropylene (PP), polyethylene (PE) and the like are preferable. The above thermoplastic resin alone may be used, but heat resistance, dimensional stability and rigidity are increased by mixing inorganic materials such as glass fiber and carbon and metal, and coloring and heat resistance are improved by mixing pigments and stabilizers. May be raised. You may use the composite material of materials other than the said thermoplastic resin and the said thermoplastic resin, for example, rubber | gum, resin, etc.

  Although there is no restriction | limiting in particular about the shaping | molding method of the support body 10, Methods, such as injection molding and cutting, are mentioned.

  The toner container ventilation filter 1 is attached to the support 10 by the adhesive layer 4 included in the toner container ventilation filter 1 in the example shown in FIG. 12A. If it does not occur, the attachment method is not particularly limited, and it may be attached by heat welding, ultrasonic welding, vibration welding, adhesion with an adhesive, or the like. In particular, simple heat welding, ultrasonic welding, or the like is preferable. The toner container ventilation filter 1 may be disposed in a mold for molding the support 10, and the toner container ventilation filter 1 and the support 10 may be integrated at the same time as the support 10 is molded by an insert molding method.

  As shown in FIGS. 12A and 12B, the toner container ventilation filter 1 is attached to the support 10 in a state where the ventilation member 11 is attached to the ventilation portion 23a of the container 23 in which the toner 20 is accommodated. The PTFE porous membrane 2 may be arranged on the toner 20 side, or the breathable support layer 3 may be arranged on the toner 20 side as shown in FIGS. 13 (a) and 13 (b). It may be attached to the support 10. If the PTFE porous membrane 2 is disposed on the toner side with the ventilation member 11 attached to the container 23, the toner releasability with respect to the toner container ventilation filter 1 is good, and the ventilation support layer 3 is on the toner side. If it arrange | positions, since the air permeable support layer 3 functions as a pre filter, clogging of the PTFE porous membrane 2 can be suppressed.

  FIGS. 12B and 13B show an example of the toner container 21 to which the ventilation member 11 shown in FIGS. 12A and 13A is attached. As shown in FIGS. 12B and 13B, the toner container 21 has a space in which the ventilation member 11 in which the toner container ventilation filter 1 is attached to the support 10 accommodates the toner 20 therein. The container 23 is attached to the vent 23a. In FIGS. 12B and 13B, reference numeral 23b denotes an opening, and 24 denotes a shutter that covers the opening 23b.

  When the toner container 23 filled with the toner 20 is attached to an image forming apparatus such as a laser printer or a facsimile, the shutter 24 is slid, and the toner 20 is sent from the opening 23b to a drawing unit such as a printer head.

  The ventilation member 11 can be attached to the container 23 by, for example, a method such as ultrasonic welding, heat welding, vibration welding, or press fitting. The ventilation member 11 may be attached to the container 23 by fitting or screwing, for example, by providing a screw groove or a fitting groove or the like in the support 10 and the ventilation portion 23a. Attachment by press-fitting, fitting, and screwing is preferable because the ventilation member 11 can be easily replaced. As shown in FIG. 14, the ventilation member 11 may be attached to the container 23 by the adhesive 13.

  The number of ventilation members 11 attached to the container 23 is not particularly limited, and a plurality of ventilation members 11 may be attached to the other surface of the container 23 or the same surface. When a plurality of ventilation members 11 are attached, the ventilation of the toner container 23 of the at least one ventilation member 11 is prevented from being blocked by the toner regardless of the position of the toner container 23 containing the toner. It is preferable to determine the attachment position of the member 11.

  The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the following examples.

A toner container ventilation filter 1 having the structure shown in FIG. 4 was produced as follows. PTFE porous membrane 2 (manufactured by Nitto Denko Corporation, “Microtex NTF1033”, thickness 15 μm, average pore diameter 3 μm, collection efficiency 100%, Frazier air permeability 10 cm ³ · cm ⁻² · s ⁻¹ ) and melt blown method The produced PP non-woven fabric 3 (thickness 300 μm, collection efficiency 81.0%, fragile air permeability 12 cm ³ · cm ⁻² · s ⁻¹ , basis weight 40 g / m ² ) and polyolefin adhesive The adhesive was laminated at 150 ° C.

Next, a 5 mm through hole was formed in the pressure-sensitive adhesive sheet 4 with a release sheet (manufactured by Nitto Denko Corporation, “No. 500”) by punching, and the release sheet was peeled off and bonded to the PTFE porous membrane 2. These were punched out to an outer diameter of 12 mm to produce a toner container ventilation filter (collection efficiency 100%, Frazier permeability 2 cm ³ · cm ^-2 · s ^-1 ).

Instead of PP non-woven fabric (thickness 300 μm, collection efficiency 81.0%, fragile air permeability 12 cm ³ · cm ^-2 · s ^-1 , basis weight 40 g / m ² ), PP made by the same melt blown method For a toner container as in Example 1 except that a non-woven fabric (thickness 160 μm, collection efficiency 70%, Frazier air permeability 25 cm ³ · cm ⁻² · s ⁻¹ , basis weight 20 g / m ² ) was used. A ventilation filter (collection efficiency 100%, Frazier permeability 3 cm ³ · cm ^-2 · s ^-1 ) was produced.

In place of PP non-woven fabric (thickness 300 μm, collection efficiency 81.0%, fragile air permeability 12 cm ³ · cm ⁻² · s ⁻¹ , basis weight 40 g / m ² ), PP made by the same melt blown method For a toner container as in Example 1 except that a non-woven fabric (thickness 150 μm, collection efficiency 61%, fragile air permeability 30 cm ³ · cm ⁻² · s ⁻¹ , basis weight 15 g / m ² ) was used. A ventilation filter (collection efficiency 100%, Frazier permeability 3.5 cm ³ · cm ^-2 · s ^-1 ) was produced.

Instead of PP nonwoven fabric (thickness 300 μm, collection efficiency 81.0%, Frazier air permeability 12 cm ³ · cm ^-2 · s ^-1 , basis weight 40 g / m ² ), it is produced by the melt blown method and further electret treated Example 1 except that the PP non-woven fabric (thickness 160 μm, collection efficiency 99.0%, fragile air permeability 25 cm ³ · cm ⁻² · s ⁻¹ , basis weight 20 g / m ² ) was used. Thus, a toner container ventilation filter (collection efficiency 100%, Frazier permeability 3 cm ³ · cm ^-2 · s ^-1 ) was produced.

Instead of PP non-woven fabric (thickness 300 μm, collection efficiency 81.0%, fragile air permeability 12 cm ³ · cm ⁻² · s ⁻¹ , basis weight 40 g / m ² ), non-woven fabric containing PP fiber and glass fiber (Toner container as in Example 1 except that (thickness 200 μm, collection efficiency 97.0%, Frazier air permeability 10 cm ³ · cm ⁻² · s ⁻¹ , basis weight 50 g / m ² )) was used. Ventilation filters (collection efficiency 100%, Frazier permeability 2.5 cm ³ · cm ^-2 · s ^-1 ) were produced.

(Comparative Example 1)
Instead of PP non-woven fabric (thickness 300 μm, collection efficiency 81.0%, Frazier air permeability 12 cm ³ · cm ⁻² · s ⁻¹ , basis weight 40 g / m ² ), PP non-woven fabric (thickness 200 μm, trapping) A toner container ventilation filter (collection) in the same manner as in Example 1 except that a collection efficiency of 20.0%, a fragile permeability of 200 cm ³ · cm ^-2 · s ^-1 , and a basis weight of 30 g / m ² were used. An efficiency of 100% and a fragile air permeability of 5 cm ³ · cm ^-2 · s ^-1 ) were produced.

As shown in FIG. 12A, the toner container ventilation filters of Examples 1 to 5 and Comparative Example 1 are fixed to the support 10 to form the ventilation member 11, and these ventilation members 11 are respectively shown in FIG. 12B. As shown, a toner container 21 was prepared by attaching to a container 23 containing toner 20 (commercially available product: cyan toner, average particle diameter 5 μm). The volume in the container is 500 cm ³ and the toner capacity is 250 cm ³ . Before attaching the ventilation member 11 to the container 23, a stainless needle (outer diameter × inner diameter 0.47 mm × 0.115 mm) was pierced into the PTFE porous film 2 to form a pinhole in the PTFE porous film 2.

  After the toner container was dropped 10 times from a height of 30 cm, the toner leakage from the toner container ventilation filter was confirmed. As shown in Table 1, in the toner container ventilation filter of Examples 1 to 5, the toner Leakage was not confirmed, but toner leakage was confirmed in the toner container ventilation filter of Comparative Example 1. From the above results, in the air filter for a toner container in which the collection efficiency of the air-permeable support layer 3 is 60% or more, the air-permeable support layer can suppress toner leakage even if pinholes are generated in the PTFE porous film. It could be confirmed.

PTFE porous membrane (manufactured by Nitto Denko Corporation, “Microtex 1131”, thickness 80 μm, average pore diameter 1 μm, collection efficiency 100%, fragile air permeability 0.66 cm ³ · cm ⁻² · s ⁻¹ ) and air permeability As a support layer, a PP non-woven fabric (fiber diameter 0.5-3 μm, basis weight 30 g / m ² , collection efficiency 80%, Frazier permeability 20 cm ³ · cm ^-2 · s ^-1 ) is prepared, and a PTFE porous membrane And a breathable support layer were superposed and passed between a pair of rolls heated to 130 ° C. to obtain a toner container vent filter.

As a breathable reinforcing layer between the PTFE porous membrane and the PP nonwoven fabric, a PP nonwoven fabric (fiber diameter 20-30 μm, basis weight 30 g / m ² , collection efficiency 10%, fragile air permeability 200 cm ³ · cm ^-2 · A toner container ventilation filter was produced in the same manner as in Example 6 except that s ^-1 ) was further provided. The air-permeable support layer and the air-permeable reinforcing layer are thermally laminated by passing between a pair of rolls heated to 130 ° C., and then a laminate including the air-permeable support layer and the air-permeable reinforcing layer and the PTFE porous membrane are formed. Similarly, the gas-permeable reinforcing layer and the PTFE porous membrane were joined by passing between a pair of rolls heated to 130 ° C.

(Comparative Example 2)
PP non-woven fabric (fiber diameter 20 μm to 30 μm) instead of PP non-woven fabric (fiber diameter 0.5 μm to ³ μm, basis weight 30 g / m ² , collection efficiency 80%, Frazier air permeability 200 cm ³ · cm ⁻² · s ⁻¹ ) A toner container ventilation filter was obtained in the same manner as in Example 7, except that a basis weight of 30 g / m ² and a collection efficiency of 10% were used.

  The pressure loss was measured according to the following method for Examples 7 and 8 and Comparative Example 2, and the results are shown in FIG.

[Pressure loss] Set the sample in a circular holder so that the effective area is 100 cm ² , and adjust the permeation flow rate of air to the sample to 5.3 cm / sec by applying a pressure difference between the upstream side and the downstream side. However, the pressure loss at regular intervals was measured with a pressure gauge. The sample was set in the holder so that the air-permeable support layer was on the upstream side of the gas flow.

  As shown in FIG. 15, the collection efficiency measured using particles (atmospheric dust) having a particle diameter of 1 μm to 5 μm, including a porous PTFE membrane and a breathable support layer, having a particle diameter of 1 μm to 5 μm. As described above, it was confirmed that the increase in pressure loss could be suppressed and the life of the toner container ventilation filter could be extended.

  Since the toner container ventilation filter of the present invention has a long life, the toner container ventilation filter of the present invention and the toner container using the same are useful.

(A) is sectional drawing which shows an example of the ventilation filter for toner containers of this invention, (b) is a bottom view of (a). Sectional drawing which shows the other example of the ventilation filter for toner containers of this invention (A) is sectional drawing which shows the other example of the ventilation filter for toner containers of this invention, (b) is a bottom view of (a). Sectional drawing which shows the other example of the ventilation filter for toner containers of this invention (A) is a perspective view which shows an example of the ventilation filter assembly for toner containers of this invention, (b) is an expanded sectional view of the part A of (a). The partial cross section figure which shows the other example of the ventilation filter aggregate for the toner container of this invention FIG. 6 is a perspective view showing another example of a ventilation filter assembly for a toner container of the present invention. (A) is a perspective view showing an example of the toner container of the present invention, (b) is a partial sectional view of (a). (A) is a perspective view showing another example of the toner container of the present invention, (b) is a cross-sectional view taken along line II ′ of (a). The perspective view which shows the other example of the toner container of this invention (A) and (b) are diagrams for explaining a state in which the toner container ventilation filter shown in FIG. 3 is attached to the container, and (c) is a sectional view showing another example of the toner container ventilation filter of the present invention. (A) is sectional drawing which shows an example of the ventilation member of this invention, (b) is sectional drawing which shows the other example of the toner container of this invention. (A) is sectional drawing which shows the other example of the ventilation member of this invention, (b) is sectional drawing which shows the other example of the toner container of this invention. Sectional drawing which shows the other example of the ventilation member of this invention The graph which showed the result of having measured pressure loss about an example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Breathable filter for toner containers 2 PTFE porous membrane 3 Breathable support layer 4 Adhesive layer 5 Breathable reinforcement layer 10 Support body 23 Container 23a Vent part 11 Breathing member 21 Toner container

Claims (13)

  A ventilation filter for a toner container including a polytetrafluoroethylene porous membrane and a breathable support layer, wherein the collection efficiency of the breathable support layer measured using particles having a particle diameter of 1 μm to 5 μm is 60%. A toner container ventilation filter characterized by the above.   The air filter for a toner container according to claim 1, wherein the air-permeable support layer is a nonwoven fabric.   The ventilation filter for a toner container according to claim 1, wherein at least a part of one surface is formed from the air permeable support layer.   The ventilation filter for a toner container according to claim 1, wherein at least a part of one surface is formed of the polytetrafluoroethylene porous film.   The ventilation filter for a toner container according to claim 3, further comprising an adhesive layer, wherein a peripheral edge of the one surface is formed from the adhesive layer.   Further comprising a breathable reinforcing layer, the breathability of the breathable reinforcement layer measured according to JIS L 1096 is higher than the breathability of the breathable support layer measured according to JIS L 1096. Item 6. The toner container ventilation filter according to any one of Items 1 to 5.   The ventilation filter for a toner container according to any one of claims 1 to 6, wherein the air-permeable support layer is electret-treated.   The ventilation filter for a toner container according to any one of claims 1 to 7, which has been subjected to a liquid repellent treatment.   A toner container comprising a plurality of toner container ventilation filters according to claim 1, wherein the plurality of toner container ventilation filters are detachably attached to a sheet-like material. Aeration filter assembly.   The air filter assembly for a toner container according to claim 9, wherein the sheet material is in a band shape, and the sheet material on which the plurality of toner container air filters are attached is wound up in a roll shape.   9. A toner container ventilation filter according to claim 1 and a support having a through hole, wherein the toner container ventilation filter is attached to the support so as to cover the through hole. A ventilation member characterized by being made.   9. A toner container, wherein the toner container ventilation filter according to claim 1 is attached to a ventilation portion of a container having a space for containing toner.   12. A toner container, wherein the ventilation member according to claim 11 is attached to a ventilation part of a container having a space for containing toner.