JPS63106689A - Cleaning blade for photosensitive body of copying machine - Google Patents

Abstract

PURPOSE:To eliminate an abnormal sound generated by the friction between a blade and a photosensitive body in copying operation by holding a blade main body made of a rubber compound on a holder made of a specific high- elasticity material. CONSTITUTION:The blade main body 1 made of the rubber compound is held on the holder 2 made of the high-elasticity material consisting principally of resin with a >=50,000kg/cm<2> modulus of elasticity. Here, the holder 2 is preferably made of resin reinforced by a reinforcing material, which is preferably metal, glass fiber, or carbon fiber. Further, the rubber compound in use contains a 15-70wt% styrene-based block copolymer, a 0-70wt% plasticizer, and a 5-60wt% olefin processing aid. Consequently, the abnormal sound generation of a blade used for the cleaning of various copying machine photosensitive bodies is eliminated, and cleaning performance and the durability of the blade are improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a photoconductor cleaning blade for copying machines, and in particular, it solves problems such as generation of abnormal noise in blades used for cleaning photoconductors of various copying machines. This invention relates to a copying machine photoreceptor cleaning blade that has improved cleaning performance and blade durability.

[Prior Art] Copying machines commonly used today uniformly charge a photoreceptor coated with a photoconductor such as selenium, zinc oxide, cadmium sulfide, or polyvinylcarbazole, and then project an original image on it. A charged image is formed according to the amount of light, colored particles (toner) charged with the opposite polarity are brought into contact with the electrostatic charger, an image is formed, and this image is transferred to another piece of paper and viewed while fixed. The principle is that the photoreceptor can be cleaned and used repeatedly. To clean the photoreceptor, a cleaning blade is installed to come into contact with the surface of the photoreceptor and scrape off toner adhering to the surface of the photoreceptor.

Conventionally, methods for bringing the photoconductor cleaning blade of a copying machine into contact with the photoconductor include: (1) a normal pressure contact method in which the blade is always in contact with the photoconductor; (2) a spring pressure contact method in which the blade is brought into contact only during copying using a spring; There is. Further, in the above-mentioned methods (1) and (2), as a blade fixing means for pressing the blade into contact with the photoreceptor, a method is adopted in which a metal holder is used and the blade is adhered to and held.

[Problems to be Solved by the Invention] The conventional blade uses a metal holder as described above, but since this metal holder is heavy in weight (73), the spring pressure welding method requires ■ a large spring. ■ There are problems such as the load on the spring becomes large and the durability of the spring is low.

On the other hand, the normal pressure contact method has a problem in that cleaning performance is reduced due to warping of the holder and distortion generated during bonding to the holder.

Moreover, in both the normal pressure welding method and the spring pressure welding method, if frictional sound vibration is generated due to friction between the photoreceptor and the blade during copying, it will resonate with the metal holder, and the sound will be amplified and produce a considerable amount of abnormal noise. occurs, which poses a major problem in use.

[Means for Solving the Problems] The present invention solves the above conventional problems, and includes a blade main body made of a rubber compound with an elastic modulus of 50.0.
00kg/crr? The object of the present invention is to provide a photoconductor cleaning blade for a copying machine, which is held in a holder made of a highly elastic material mainly composed of the above-mentioned resin.

The present invention will be explained in detail below.

The copying machine photoreceptor cleaning blade of the present invention has a blade body made of a rubber compound with an elastic modulus of 50,000 k.
It is held in a holder made of a highly elastic material with a tensile strength of more than 100 g/cm.

Examples of the form of the holder for holding the blade main body of the present invention include: (1) a holder made of resin, (2) a holder in which a reinforcing member such as a metal plate or a metal rim is bonded or laminated to a resin plate, and the like. It will be done. The resin that makes up the holder is thermoplastic,
Any type of thermosetting material may be used, maintains cleanability,
To prevent resonance, the elastic modulus of the resin must be 50,000
(50,000) kg/crr? or more, and particularly desirably 100,000 kg/cm” or more. In addition, in order to satisfy the elastic modulus of the holder required by the present invention, these resins are made of glass fiber. , or may be reinforced with reinforcing 1a fibers such as carbon fibers.

In the present invention, specific examples of the form in which the blade body is held by the holder include the following methods (1) to (4).

(2) As shown in FIG. 1, the plate surface along one long side of the blade body 1 is bonded with adhesive or the like along one long side of the flat plate-shaped holder 2.

■ As shown in Figure 2, a holder 3 whose plate surface along one long side of the blade body 1 is bent into a crank-shaped cross section.
Glued with adhesive, etc. along the long side of the eldest flat plate.

■ As shown in Figure 3, the plate surface along one long side of the blade body 1 is bent into a crank-shaped cross section on the negative side, and a space 4a for clamping is created between the stacked flat plates. It is inserted into the space 4a of the formed holder 4 and adhered with adhesive or the like.

In addition, in the present invention, the material of the blade body is as follows:
Thermosetting urethane, etc., which have been conventionally commonly used for blades, may be used, but preferably 15 to 70% by weight of a styrenic block copolymer, 0 to 70% by weight of a plasticizer, and 5 to 60% by weight of an olefin processing aid. %.

In this case, examples of the styrene block copolymer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, etc. is 10,000 to 300,000
It is preferable that it is in the range of . Further, the styrene content is preferably 10 to 50% by weight, preferably 10 to 35% by weight. In the present invention, among the above styrene block copolymers, styrene-ethylene-
Butylene-styrene block copolymers are particularly preferred because they have excellent chlorine resistance, weather resistance, heat resistance, ozone resistance, and oil resistance. These styrenic block copolymers can be used alone or in combination of two or more.

Liquid polychloroprene as a binder? ? Examples include low molecular weight olefin polymers such as type Ii isodiisobutylene-isoprene copolymer polyisoprene, liquid polybutadiene, low molecular weight polyisobutylene, low molecular weight atactic polypropylene, and oils such as castor oil, tall oil, and paraffin oil. . Among these, the viscosity is 90
Paraffin oils and naphthenic oils with a viscosity of 300 cst or more are preferred, and oils with a viscosity of 300 cst or more are particularly preferred because they cause less migration and provide good formulations.

In addition, as olefin processing aids, polyethylene,
Examples include polypropylene, ethylene-propylene copolymer, etc., and among them, polypropylene and ethylene-propylene block copolymer are preferred.

The thermoplastic rubber compound of the present invention contains 15 to 70% by weight, 0 to 70% by weight, and 5 to 60% by weight of these styrenic block copolymers, plasticizers, and olefinic processing aids, respectively. Of these, the blending amount of the olefin processing aid is preferably 10 to 15% by weight.

Furthermore, in the present invention, an olefin rubber modifier may be added in addition to the above components in order to change, mainly reduce, the hardness of the resulting rubber compound and to reduce costs. As the olefinic rubber modifier, ethylene-propylene rubber copolymers, particularly ethylene-propylene-diene terpolymers are preferred. This olefin-based rubber modifier can be used not only by adding a separate compound in addition to the above-mentioned components, but also by cross-linking the olefin-based processing aid by means such as dynamic vulcanization. can be given. If the amount of the olefin rubber modifier is too small, the hardness will increase, and if it is too large, the strength at high temperatures (60° C. or higher) will be significantly reduced, which is not preferable. For this reason, the blending amount of the olefin rubber modifier is 10 to 50% of the total polymer.
Preferably it is 0 phr.

In addition, suitable fillers and reinforcing materials can be appropriately blended as necessary for the purpose of imparting various properties to the resulting rubber compound. Examples of fillers or reinforcing materials include clay, talc, calcium carbonate, magnesium carbonate, white carbon such as silica and calcium silicate, barium sulfate, and mica, which are appropriately selected and blended depending on the purpose. Preferred blending amount of these fillers or reinforcing materials −
is 10-200 phr based on total polymer.

Furthermore, other general-purpose compounding agents such as colorants, stabilizers, tackifier resins, etc. can also be compounded.

If the rubber compound consists of such components and composition,
It has an extremely good balance of hardness, compression set, and plasticizer migration, such as hardness of 50 to 75 (JIS A),
Compression set (JIS K2SO3, 70℃×22hr
) A good thermoplastic rubber compound in the range of 30-40% is provided, resulting in blades with significantly better properties.

[Function] In the cleaning blade of the present invention, the holder that holds the blade has an elastic modulus of 50,000 kg/crr? Since it is made of a highly elastic material mainly composed of the resin mentioned above, it reduces abnormal noise caused by the resonance of sound vibrations generated by the friction between the blade and the photoreceptor during copying, as is clear from the results of the examples described later. Or it can be resolved.

In addition, because conventional metal holders are made by punching, bending, pressing, etc., it is difficult to create ribs or bosses to solve the problem of noise generation.
The holder mainly made of resin according to the present invention is extremely easy to process in this manner.

Furthermore, when a rubber compound containing 15 to 70% by weight of a styrene block copolymer, 0 to 70% by weight of a plasticizer, and 5 to 60% by weight of an olefinic processing aid is used as the material for the blade body, Such a rubber compound is a thermoplastic rubber compound having appropriate hardness, compression set, and desensitizing properties, so when it is used as a cleaning blade for an organic photoreceptor, it does not interact with the organic photoreceptor. Frictional energy causes microflow at the contact site, which behaves like a viscous fluid. Therefore, it is possible to reliably prevent the organic photoreceptor from being scraped or damaged, and to significantly reduce abnormal noise due to resonance, thereby making it possible to provide a cleaning blade having good leaning performance.

[Examples] The present invention will be described below in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof.

Example 1 Cleaning holder Not~ configured as shown in Fig. 1
No. 4 was manufactured, installed in an actual machine, and used for cleaning the photoreceptor, and the relationship between the elastic modulus of the holder and the generation of abnormal noise was investigated. The results are shown in Figure 4.

The material of the blade body is a thermoplastic rubber compound.
The following materials were used for the holder.

Holder material Not: Modified polyphenylene oxide No. 2 Glass-filled modified polyphenylene oxide No. 3 Glass-filled nylon No. 4: Polyphenylene sulfide In addition, the abnormal noise generation situation in Fig. 4 is a 5-level evaluation of the abnormal noise level, where 5 is abnormal noise. The criteria for judgment are none, 4 means a little abnormal noise, 3 means moderate abnormal noise, 2 means slightly loud abnormal noise, and 1 means quite loud abnormal noise.

From FIG. 4, it is clear that the cleaning blade of the present invention having a bending modulus of elasticity of 50,000 kg/crd or more significantly reduces the generation of abnormal noise during copying. Also,
It is observed that when the bending elastic modulus becomes 100,000 kg/c ni'' or more, the abnormal noise further decreases.

[Effects of the Invention] As detailed above, the copying machine photoreceptor cleaning blade of the present invention has a blade main body made of a rubber compound made of a highly elastic material mainly made of resin with an elastic modulus of 50,000 kg/c or more. It is possible to reduce or eliminate abnormal noise caused by resonance of sound vibrations generated by friction between the blade and the photoreceptor during copying. Moreover, by effectively preventing resonance in this way, it is possible to improve the durability of the blade and significantly improve the cleaning efficiency.

[Brief explanation of the drawing]

FIGS. 1 to 3 are perspective views each showing a configuration example of a cleaning blade of the present invention. Figure 4 shows Example 1
2 is a graph showing the relationship between the elastic modulus of the holder obtained in 1 and the abnormal noise generation situation. 1...Blade body, 2-4...Holder.

Claims (4)

[Claims] (1) The blade body is made of a rubber compound and has an elastic modulus of 5.
A photoconductor cleaning blade for a copying machine, characterized in that it is held in a holder made of a highly elastic material mainly made of resin with a tensile strength of 0,000 kg/cm^2 or more. (2) The cleaning blade according to claim 1, wherein the holder is made of resin reinforced with a reinforcing material. (3) The cleaning blade according to claim 2, wherein the reinforcing material is metal, glass fiber, or carbon fiber. (4) The rubber compound is a styrenic block copolymer 1
5 to 70% by weight, 0 to 70% by weight of a plasticizer, and 5 to 60% by weight of an olefinic processing aid, according to any one of claims 1 to 3. cleaning blade.