JP2001051565A - Cleaning blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cleaning blade having superior edge accuracy and excellent in low frictional property by allowing a specified % or more of silicon atoms to exist on the end face of a cleaning blade formed by cutting by the sticking of an organosiloxane and oxygenation treatment. SOLUTION: A plate made of a cured body 4 of a polyurethane resin composition is cut to form a cleaning blade 1. An organosiloxane is stuck to the end face 3 of the cleaning blade 1 by dipping and the end face 3 is subjected to oxygenation treatment to allow >=4 at.% silicon atoms (Si) to exist on the end face 3. The coefficient of friction can further be lowered by making the ratio (O/C) of the number of oxygen atoms (O) to the number of carbon atoms (C) in the end face 3 >=1.15 times that in the interior of the cleaning blade.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning blade for removing toner remaining on the outer peripheral surface of a photosensitive drum of an electrophotographic copying machine or the like.

[0002]

2. Description of the Related Art As an electrophotographic copying machine, an outer peripheral surface of a photosensitive drum is uniformly charged, and then the outer peripheral surface thereof is exposed through a copy image of a copying object, thereby forming an electrostatic latent image on the outer peripheral surface. Generally, an image is formed, a charged toner is attached to the electrostatic latent image to form a toner image, and copying is performed by transferring the toner image to copy paper or the like.

In such an electrophotographic copying machine, since toner remains on the outer peripheral surface of the photosensitive drum after the transfer of the toner image, the toner is transferred onto the outer peripheral surface of the photosensitive drum, for example, by a plate-like holder 22 as shown in FIG. Cleaning blade 21 supported
, And the residual toner is scraped off with this to remove it.

As the elastic body used for the cleaning blade 21, a polyurethane resin having excellent mechanical properties such as abrasion resistance has been awarded. However, if the cleaning blade 21 made of such a polyurethane resin is used for a long period of time, the tip of the cleaning blade 21 (the portion in contact with the photosensitive drum) that is in sliding contact with the photosensitive drum is worn, and the residual toner There is a problem that removal cannot be performed well.

In order to improve the wear resistance of the cleaning blade 21, various attempts have been made to reduce the friction of the polyurethane resin surface.
For example, a method of coating a polyurethane resin surface (JP-A-4-260084, JP-A-4-21211)
No. 90, etc.) and a method of dispersing a lubricant in a polyurethane resin (JP-A-7-306616, JP-A-5-158389, JP-A-5-173664, etc.).

[0006]

However, the above-mentioned method of coating the surface of the polyurethane resin is effective in reducing the friction at the initial stage, but does not provide excellent edge accuracy over a long period of time. There is. Also, the method of dispersing the lubricant,
There is a problem that a new process such as a process of uniformly dispersing and mixing the lubricant inside the polyurethane resin is required, and it is not possible to improve the production efficiency. At this time, when the solid lubricant is dispersed, there is a problem that the viscosity of the polyurethane resin composition for forming the cleaning blade becomes high, and the workability is deteriorated. On the other hand, when the liquid lubricant is dispersed, there is a problem that the bleed out of the liquid lubricant adversely affects an image.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cleaning blade having excellent edge accuracy and excellent low friction.

[0008]

In order to achieve the above object, a cleaning blade according to the present invention is a cleaning blade formed by cutting a plate made of a cured polyurethane resin composition. Silicon atoms (Si) at 4 atm by adhesion of organic siloxane and oxygenation treatment on the end face of the cleaning blade formed by
om% or more.

In other words, the present inventors have conducted intensive studies in order to obtain a cleaning blade having excellent edge accuracy and low friction. As a result, an organic siloxane is attached to the end surface of the cleaning blade formed by the above-described cutting, for example, by dipping.
Thereafter, the end face of the cleaning blade is subjected to oxygenation treatment, so that 4 silicon atoms (Si) are formed on the end face.
It has been found that the desired object can be achieved by making the content of atom% or more, and the present invention has been achieved.

Here, the oxygenation treatment means an ultraviolet irradiation treatment,
This refers to a process of generating active oxygen, such as a corona discharge process, a plasma discharge process, or an ozone atmosphere process, and using the active oxygen to cause a chemical change or the like.

The organic siloxane is defined as methylhydroxy polysiloxane, methylhydropolysiloxane,
It is an organic substance containing silicone as a main component such as polydimethylsiloxane and used as it is or used as a coating solution after being dissolved in a solvent. Here, the “main component” is a main component constituting the organic siloxane, and means a component that greatly affects the properties of the composition, and includes a case where the whole consists only of the main component.

By making the end face of the cleaning blade in this way, the edge accuracy is improved, and
Low friction is promoted, but the reason is not always clear. However, it is presumed to be due to the following reasons. That is, when an organic siloxane is adhered to the end surface (cut surface) of the cleaning blade by dipping or the like, and then the end surface of the cleaning blade is subjected to a surface modification treatment (oxygenation treatment) such as ultraviolet irradiation. The organic siloxane adhering to the end surface of the cleaning blade is oxidized and changes to a silica (SiO ₂ ) (glassy) state. At this time, it is considered that by performing the oxygenation treatment so that silicon atoms (Si) are present at 4 atom% or more, the edge accuracy is improved and the low friction property is improved.

According to the present invention, since only the end face of the cleaning blade is modified by the oxygenation treatment, the properties of the polyurethane elastomer such as mechanical strength and elastic pressure contact property are not impaired, and the cleaning performance is not deteriorated. . Further, in the cleaning blade of the present invention, since the organic siloxane on the end face is considered to exhibit adhesion by increasing the polarity of the organic siloxane and the polyurethane by the oxygenation treatment,
The adhesion between the organosiloxane and the cured polyurethane resin composition, which was originally difficult to obtain, can be sufficiently obtained. In addition, an effect can be obtained in a short time by the oxygenation treatment. Therefore, the effect of improving the manufacturing efficiency can be obtained.

In the present invention, it is important that silicon atoms (Si) be present at 4 atom% or more on the end face of the cleaning blade. Here, the silicon atom (Si) is 4 at.
that there more om%, the total atomic (object element: ³ Li~ ⁹⁸ Cf) present on the end face of the cleaning blade means that the ratio of the occupied silicon atoms (Si) is not less than 4Atom%, which is, X-rays The value derived by analyzing the surface by photoelectron spectroscopy [ESCA] is 4 at.
om% or more.

In particular, when the ratio (O / C) between the number of oxygen atoms (O) and the number of carbon atoms (C) on the end face is set to 1.15 times or more the O / C ratio inside the cleaning blade. , The coefficient of friction can be further reduced. The numerical values here are also values derived by the ESCA elemental analysis. Here, “inside” of the inside of the cleaning blade refers to a portion below the surface of the cleaning blade that has not been subjected to the oxygenation treatment.

[0016]

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

The cleaning blade 1 of the present invention comprises, for example, a cured polyurethane resin composition 4 as shown in FIG. 1 and is supported by a plate-like holder 2 and used for use. The above-described processing is performed on the end surface 3 of the cleaning blade 1.

As a material for forming the cured polyurethane resin composition 4 in the cleaning blade 1, a polyurethane resin composition containing a polyisocyanate and a polyol is used.

The polyisocyanate is not particularly restricted but includes, for example, 4,4'-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), and 2,6-tolylene diisocyanate. Isocyanate (2,6-TDI), 3,3'-vitrilen-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate,
2,4-tolylene diisocyanate uretidine dione (a dimer of 2,4-TDI), 1,5-naphthylene diisocyanate, metaphenylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate ( Water-added MDI), carbodiimide-modified MDI, orthotoluidine diisocyanate, xylene diisocyanate, paraphenylene diisocyanate, diisocyanate such as lysine diisocyanate methyl ester, triisocyanate such as triphenylmethane-4,4 ', 4 "-triisocyanate, polymeric MDI, etc. These are used singly or in combination of two or more. Among them, MDI is preferred from the viewpoint of abrasion resistance.

Examples of the polyol used together with the polyisocyanate include polyester polyols such as polyester diol and polyester triol, and polyether polyols such as polycaprolactone, polycarbonate, polyoxytetramethylene glycol and polyoxypropylene glycol. These may be used alone or in combination of two or more. The number average molecular weight (Mn, hereinafter simply referred to as “molecular weight”) of the polyol is preferably set in the range of 1500 to 3000. More preferably, 1500-2
The range is 500. That is, the molecular weight is 1500
When the molecular weight is less than 3000, the physical properties of the cleaning blade 1 obtained tend to decrease, and when the molecular weight exceeds 3000, the workability tends to deteriorate. In addition, this molecular weight is based on the hydroxyl value (mg
(KOH / g) based on the following equation (1).

[0021]

(Equation 1)

The polyester polyol is preferably a hydroxyl polyester polyol produced from a polybasic organic acid and a polyol and having a hydroxyl group as a terminal group.

The polybasic organic acid is not particularly limited, and may be a saturated fatty acid such as oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid or isosebacic acid. And dicarboxylic acids such as unsaturated fatty acids such as maleic acid and fumaric acid, and aromatic acids such as phthalic acid, isophthalic acid and terephthalic acid. Further, acid anhydrides such as maleic anhydride and phthalic anhydride, and dialkyl esters such as dimethyl terephthalate can also be used. Furthermore, dimer acids obtained by dimerization of unsaturated fatty acids can also be used. These may be used alone or in combination of two or more.

The polyol used together with the polybasic organic acid is not particularly limited, and may be ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, or the like.
Examples include diols such as 1,6-hexylene glycol, triols such as trimethylolethane, trimethylolpropane, hexanetriol and glycerin, and hexaols such as sorbitol. These may be used alone or in combination of two or more.

The polyether polyol is preferably produced by ring-opening polymerization or copolymerization of a cyclic ether.

The cyclic ether is not particularly restricted but includes ethylene oxide, propylene oxide, trimethylene oxide, butylene oxide,
α-methyltrimethylene oxide, 3,3′-dimethyltrimethylene oxide, tetrahydrofuran, dioxane, dioxamine and the like.

In the present invention, as the polyol used together with the polyisocyanate, polybutylene adipate (PBA), which is excellent in abrasion resistance, is preferable among the above series.

In the polyurethane resin composition used in the present invention, in addition to the above polyisocyanate and polyol,
A chain extender, a foaming agent, a surfactant, a flame retardant, a colorant, a filler, a plasticizer, a stabilizer, a release agent, a catalyst and the like may be contained.

The chain extender is not particularly limited as long as it is a conventionally known one.
Butanediol (1,4-BD), ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, xylene glycol, triethylene glycol, trimethylolpropane (TMP), glycerin,
Polyols having a molecular weight of 300 or less, such as pentaerythritol, sorbitol, and 1,2,6-hexanetriol. These may be used alone or in combination of two or more.

Examples of the catalyst include amine compounds such as tertiary amines and organometallic compounds such as organotin compounds. Of these, amine compounds are preferred.

Examples of the tertiary amine include trialkylamines such as triethylamine, tetraalkyldiamines such as N, N, N ', N'-tetramethyl-1,3-butanediamine, and amino acids such as dimethylethanolamine. Alcohols, ethoxylated amines, ethoxylated diamines, ester amines such as bis (diethylethanolamine) adipate, triethylenediamine, N,
Cyclohexylamine derivatives such as N-dimethylcyclohexylamine, morpholine derivatives such as N-methylmorpholine and N- (2-hydroxypropyl) -dimethylmorpholine, N, N'-diethyl-2-methylpiperazine, N, N ' -Bis- (2-hydroxypropyl) -2
-Piperazine derivatives such as methylpiperazine and the like.

The above-mentioned organotin compounds include dibutyltin dilaurate, dibutyltin di (2-ethylhexoate)
And the like. Further, stannous 2-ethylcaproate, stannous oleate, and the like can be given.

The cleaning blade 1 of the present invention can be manufactured by using the above-mentioned materials according to a conventional method. Specifically, it can be produced according to a prepolymer method, a semi-one-shot method, or a one-shot method. Among them, the prepolymer method is preferably used from the viewpoint of excellent mechanical properties.

According to the prepolymer method, the cleaning blade 1 of the present invention is manufactured, for example, as follows. That is, first, the above-mentioned polyisocyanate and polyol are prepared, and both are blended at a predetermined ratio, and reacted under predetermined reaction conditions to prepare a urethane prepolymer (main solution). On the other hand, the above polyol, a chain extender,
A catalyst and the like are prepared, blended in a predetermined ratio, and mixed under predetermined conditions to prepare a curing agent liquid.

Then, a polyurethane resin composition solution is prepared by blending and mixing the above-mentioned base solution and curing agent solution at a predetermined ratio. Next, as shown in FIG. 2 (A), a release agent is sprayed onto the inner peripheral surface 5a of the cleaning blade molding die 5, and an adhesive treatment with the cleaning blade 1 (application of an adhesive) is performed. Is attached to the surface of the plate-shaped holder 2. In this state, the polyurethane resin composition solution is injected into the mold 5 and is cured by reaction. Then, the obtained cured product of the polyurethane resin composition 4
Is removed from the mold 5 and cut at a position indicated by a broken line X as shown in FIG. 2B to obtain two cleaning blades. The end face (cut face) of the cleaning blade formed by this cutting is coated with an organic siloxane described below and subjected to oxygenation treatment, whereby the cleaning blade shown in FIG.
It is possible to obtain a cleaning blade 1 having an end face 3 in which silicon atoms (Si) are present at a specific ratio as shown in FIG. The cleaning blade 1 is formed integrally with the plate-shaped holder 2.

The cleaning blade molding die 5 described above.
Before injecting the polyurethane resin composition solution,
Desirably, it is preheated. That is, the moldability is improved by preheating the mold 5. As described above, it is desirable that the inner peripheral surface 5a of the cleaning blade molding die 5 be coated with the release agent in advance, but is not essential. The release agent is not particularly limited, and may be a conventionally known release agent such as a silicone release agent.

The preparation of the urethane prepolymer (base liquid) using the above polyisocyanate and polyol is not particularly limited. For example, it is prepared as follows. That is, first, the polyisocyanate and the polyol are blended, mixed and reacted to obtain a urethane prepolymer. At this time, the urethane prepolymer is preferably set so that the value of NCO% calculated by the following equation (2) is in the range of 4 to 20% by weight. That is, the value of NCO% is 4
If the amount is less than 10% by weight, the viscosity of the urethane prepolymer may not be sufficiently reduced, and it may be difficult to inject the urethane prepolymer into a mold. On the other hand, if the content exceeds 20% by weight, the curing reaction becomes non-uniform, and the physical properties of the obtained urethane rubber deteriorate.

[0038]

(Equation 2)

The NCO index (NCO group / OH group) of the liquid composition (polyurethane resin composition) in which the urethane prepolymer (base liquid) prepared by the above method and the curing agent liquid are blended is 100 to 140. Is preferably set in the range. That is, when the NCO index (NCO group / OH group) is less than 100,
This is because a sufficient crosslink density cannot be obtained and no improvement in wear resistance is observed. Conversely, the NCO index (NCO index)
When the ratio of (OH group / OH group) exceeds 140, the hardness of the cleaning blade becomes too high, which damages the photosensitive drum and tends to cause image defects.

As shown in FIG. 2 (B), the organic siloxane applied to the end surface of the cleaning blade having the end surface formed by cutting at the position of the broken line X is not particularly limited. But, for example,
Examples include those containing methylhydroxy polysiloxane, methylhydropolysiloxane, polydimethylsiloxane, etc. as main components. These may be used alone or 2
More than one species may be used in combination. Among them, an organic siloxane containing polydimethylsiloxane as a main component is preferable, since the friction can be reduced after the oxygenation treatment.

The above-mentioned organic siloxane is usually in a liquid state and is used as it is or is dissolved in a solvent and used as a coating solution. Examples of the solvent include alcohols such as methanol, ethanol and isopropyl alcohol, hydrocarbons such as methyl ethyl ketone, toluene and paraffin hydrocarbons, and tetrahydrofuran (TH
F), N, N-dimethylformamide (DMF), N, N
Chlorinated solvents such as N-dimethylacetamide (DMAC) and methylene chloride.

The method of applying the organic siloxane to the end surface of the cleaning blade is not particularly limited, and may be applied by spray coating or the like in addition to dipping.

After the organosiloxane is attached to the end surface (cut surface) of the cleaning blade, the end surface of the cleaning blade is subjected to an oxygenation treatment.
As the oxygenation treatment, one of ultraviolet irradiation treatment, corona discharge treatment, plasma discharge treatment, and ozone atmosphere treatment is performed. As the ultraviolet irradiation treatment, for example,
It is performed by irradiating an ultraviolet ray with an integrated light amount of 1,000 mW · min / sec at a distance of 300 mm using an ultraviolet ray irradiation device (UB031-2A / BM, manufactured by Eye Graphics Co., Ltd.). As the corona discharge treatment, for example, a high-frequency power supply (AGI-020S, manufactured by Kasuga Electric Co., Ltd.) is used to generate corona discharge with an output of 0.25 kW. This is performed by discharging for seconds. As the plasma discharge treatment, for example, a plasma jet treatment device (PJ-1, manufactured by Kasuga Electric Co., Ltd.) is used, and a distance of 50 mm
This is performed by repeating the discharge process of moving at 0 mm / sec 20 times. As the ozone atmosphere treatment, for example, a UVC ozone aging tester (PP
HM UVC-D (manufactured by Toyo Seiki Seisaku-sho, Ltd.) using an ozone concentration of 50 pphm and a temperature of 40 ° C. for 24 hours.

The end surface of the cleaning blade of the present invention obtained as described above has silicon atoms (Si) of 4 atoms.
% Or more. More preferably, 5 to 15 atoms
% Range. That is, the silicon atom (Si) is 4 at.
If the content is less than om%, the effects of the present invention cannot be obtained.

The ratio (O / C) between the number of oxygen atoms (O) and the number of carbon atoms (C) on the end face formed by the oxygenation treatment is 1 to the O / C ratio inside the cleaning blade. If it is set to be 15 times or more, the friction coefficient can be further reduced. More preferably, it is in the range of 1.2 to 3.5 times.

Next, examples will be described together with comparative examples.

[0047]

[Example 1] [Synthesis of urethane prepolymer (base liquid)] PBA which was previously degassed in vacuum at 80 ° C for 1 hour
To 100 parts (N4010, Mn: 2000, manufactured by Nippon Polyurethane Industry Co., Ltd.), 44 parts of MDI (Millionate MT, manufactured by Nippon Polyurethane Industry Co., Ltd.) was added, and the mixture was reacted at 80 ° C. for 3 hours under a nitrogen atmosphere. %: 7.3% by weight of NCO-terminated prepolymer was obtained.

[Preparation of a curing agent liquid] 1.4. -To 100 parts of a mixture of butanediol and trimethylolpropane (60/40 by weight) with triethylenediamine (DABCO, manufactured by Sankyo Air Products) as a catalyst
Was added, and the mixture was subjected to vacuum dehydration at 80 ° C. for 1 hour to prepare a curing agent liquid.

[Preparation of Polyurethane Resin Composition Solution] When the above urethane prepolymer (main agent liquid) was vacuum degassed at 70 ° C. for 30 minutes, the above curing agent liquid was added so that the NCO index became 110. The polyurethane resin composition solution was prepared by mixing with a stirring blade for 60 seconds under reduced pressure.

[Preparation of dipping liquid (immersion liquid)] On the other hand, as a dipping liquid, polydimethylsiloxane (SH200 oil (500 mm ² / s, 25 ° C), manufactured by Dow Corning Toray Silicone Co., Ltd.) was used as a hydrocarbon solution ( IP Solvent 1620, manufactured by Idemitsu Petrochemical Co.) to a concentration of 0.1% by weight.

[Formation of cleaning blade]
As shown in FIG. 2A, a release agent is sprayed onto the inner peripheral surface 5a of the cleaning blade molding die 5 which has been preheated to 140 ° C., and then an adhesive treatment with the cleaning blade (adhesive agent) is performed. Is applied to the mold 5. Next, the polyurethane resin composition solution was poured into the mold 5 and the mixture was heated at 140 ° C. for 3 hours.
It was cured by reacting for 0 minutes to obtain a cured product 4. Then, as shown in FIG. 2 (B), after the cured body 4 is cut off at a position indicated by a broken line X after demolding, a secondary cure is performed at 100 ° C. × 10 hours, and two cleaning blades (thickness 2 mm × 240 mm in the longitudinal direction × 10 mm in the width direction).

[Immersion in Dipping Solution and Oxygenation Treatment] The end surface (cut surface) 3 of the cleaning blade was immersed in the dipping solution, and then air-dried. Next, the end face was subjected to an oxygenation treatment. The oxygenation treatment was performed by corona treatment under the following conditions. <Corona treatment> Using a high-frequency power supply (AGI-020S, manufactured by Kasuga Electric), a corona discharge was generated at an output of 0.25 kW, and corona treatment was performed for 60 seconds at a distance of 3 mm from the electrode and an angle of 15 degrees. Was.

[0053]

Example 2 A cleaning blade was manufactured in the same manner as in Example 1 except that the oxygenation treatment was performed by plasma discharge treatment under the following conditions. <Plasma discharge processing> Plasma jet processing equipment (PJ
-1, manufactured by Kasuga Electric Co., Ltd.), distance 50 mm, 20 mm
The process of moving at a rate of / sec was repeated 20 times.

[0054]

Example 3 A cleaning blade was produced in the same manner as in Example 1 except that the above-described oxygenation treatment was performed in an ozone atmosphere treatment under the following conditions. <Ozone Atmosphere Treatment> Using an UVC ozone aging tester (PPHM UVC-D, manufactured by Toyo Seiki Seisaku-sho, Ltd.), treatment was carried out for 24 hours in an atmosphere with an ozone concentration of 50 pphm and a temperature of 40 ° C.

[0055]

Example 4 A cleaning blade was manufactured in the same manner as in Example 1 except that the oxygenation treatment was performed by an ultraviolet irradiation treatment under the following conditions. <Ultraviolet irradiation treatment> Ultraviolet irradiation device (UB031-2A)
/ BM, manufactured by Eye Graphics Co., Ltd.)
mm, ultraviolet light was irradiated at an integrated light amount of 1,000 mW · min / sec.

[0056]

Comparative Example 1 A cleaning blade was prepared in the same manner as in Example 1 except that the dipping liquid was not immersed and the end face 3 was not oxygenated.

[0057]

Comparative Example 2 A cleaning blade was produced in the same manner as in Example 1 except that the dipping treatment was not performed. The oxygenation treatment for the end face 3 was performed by corona treatment under the same conditions as in Example 1.

[0058]

Comparative Example 3 A cleaning blade was produced in the same manner as in Example 1 except that the end face 3 was not subjected to the oxygenation treatment.

The cleaning blades thus obtained were measured and evaluated according to the following criteria, and the results are shown in Table 1 below.

[Silicon atomic weight (Si) and O / C ratio] An ESCA system (PHI56) was applied to the end surface of each of the obtained cleaning blades and the inside of the cleaning blade.
The ratio of oxygen atom, carbon atom, nitrogen atom and silicon atom was measured under the following measurement conditions using a No. 00 system (manufactured by ULVAC-PHI), and the silicon atom weight (Si) and the O / C ratio were calculated. That is, X-rays are irradiated using an Al monochromator (14 kV, 150 W), and the charge is corrected by an electron neutralizing gun.
0 μm, photoelectron take-out angle: 45 deg, resolution 18
7.85 passage, 0.8 eV / ste
The measurement was performed under the conditions of p and 20 time / step.

[Coefficient of Friction] The coefficient of friction was measured using the apparatus shown in FIG. That is, the tip of each obtained cleaning blade is cut out as a urethane chip 11 (thickness 2 mm × length 10 mm × width 10 mm),
After adhering the plate-like holding material 12 to one end (a part opposite to the end face of each cleaning blade), the other tip corner (the part that was the end face of each cleaning blade) is smoothed. The surface of the PET plate 16 was pressed against the surface, and the PET plate 16 was run at a constant speed in the direction of the arrow Y (doctor direction), and the friction coefficient generated at this time was measured.

[Evaluation of Abrasion Amount and Edge Linearity of Cleaning Blade]
After mounting in a 4 laser beam printer and evaluating the image output of 30,000 sheets, the wear amount of the blade edge portion and the edge linearity were evaluated. The amount of abrasion was determined by observing the abrasion state of the tip of the cleaning blade with a scanning electron microscope, measuring the cross-sectional area (U μm ² ) of the abraded part and the unit length (V μm) of the tip, and Formula (3)
, The wear amount (Wμm ³ ) was calculated.

[0063]

(Equation 3)

The change in edge linearity before and after endurance was judged by visual observation with a microscope, and the case where no change was observed was represented by ○, and the case where change was observed was represented by ×.

[0065]

[Table 1]

[0066]

[Table 2]

From the results shown in Tables 1 and 2, it can be seen that all of the products of Examples have a small amount of wear and are cleaning blades having excellent wear resistance. In addition, the edge linearity is hardly impaired by use, and low friction is realized. On the other hand, the product of the comparative example is severely abraded, the edge linearity is easily impaired, the coefficient of friction is relatively high, and the performance is inferior to the product of the example.

[0068]

As described above, the cleaning blade of the present invention is formed by cutting a plate-shaped body made of a cured polyurethane resin composition, and the end surface of the cleaning blade formed by the above-mentioned cutting is coated with an organosiloxane. Silicon atoms (Si) are present in an amount of 4 atom% or more in a form in which the adhesion of the organic siloxane is increased by adhesion and oxygenation. Further, the organic siloxane is changed into a silica state by the oxygenation treatment. Therefore, the edge accuracy is improved, and the low friction property is improved. Further, the ratio (O / O / O) of the number of oxygen atoms (O) and the number of carbon atoms (C) on the end face is determined.
C) is relative to the O / C ratio inside the cleaning blade,
When set to 1.15 times or more, the friction coefficient can be further reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a cleaning blade of the present invention.

FIG. 2A is a longitudinal sectional view showing a state in which two plate-shaped holders are attached to a cleaning blade molding die, and FIG. 2B is a pair of two sets formed by the die. It is a longitudinal cross-sectional view of the cleaning blade with a plate-shaped holding tool.

FIG. 3 is a configuration diagram of an apparatus for measuring a friction coefficient of a cleaning blade.

FIG. 4 is a partially broken configuration showing an example of a conventional cleaning blade.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cleaning blade 2 Plate holder 3 End surface 4 Cured polyurethane resin composition

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akihiro Maeda 3600 Gezu, Kita-gaiyama, Komaki-shi, Aichi Prefecture Inside Tokai Rubber Industries Co., Ltd. Address Tokai Rubber Industries Co., Ltd. (72) Inventor Tomonori Hayakawa Komaki City, Aichi Pref.

Claims (3)

[Claims] 1. A cleaning blade formed by cutting a plate-shaped body made of a cured polyurethane resin composition, wherein an organic siloxane is adhered to an end surface of the cleaning blade formed by the cutting and oxygenation treatment is performed. A cleaning blade wherein silicon atoms (Si) are present in an amount of 4 atom% or more. 2. A ratio (O / C) between the number of oxygen atoms (O) and the number of carbon atoms (C) on the end face is set to be 1.15 times or more the O / C ratio inside the cleaning blade. The cleaning blade according to claim 1, wherein 3. The cleaning blade according to claim 1, wherein the oxidation treatment performed on the end face is one of an ultraviolet irradiation treatment, a corona discharge treatment, a plasma treatment, and an ozone atmosphere treatment.