JP2001051573A - 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 a specular surface by the sticking of a silicone releasing agent and oxygenation treatment. SOLUTION: The cleaning blade 1 has a specular surface 3 formed by transfer from the specular surface of a die coated with a silicone releasing agent and comprises a cured body 4 of a polyurethane resin composition, and >=8 at.% silicon atoms (Si) are allowed to exist on the specular surface 3 by oxygenation treatment by which active oxygen is generated and a chemical change or the like is caused by utilizing the active oxygen, e.g. corona discharge treatment. 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 specular surface 3 >=1.6 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]

Means for Solving the Problems To achieve the above object, a cleaning blade of the present invention is a plate-shaped cleaning blade made of a cured polyurethane resin composition, wherein a part of the surface of the plate-shaped body is formed. It is formed on a mirror surface, and a silicon atom (Si) is present at 8 atom% or more on the surface of the mirror surface by adhesion of a silicone-based release agent and oxygenation treatment.

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, for example,
For a cleaning blade made of a cured polyurethane resin composition having a mirror surface transferred and formed by a mold mirror surface coated with a silicone release agent, silicon atoms (Si) are formed on the mirror surface by oxygenation treatment. 8 atom
%, It was found that the intended purpose could be achieved, and the present invention was reached.

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

The silicone release agent is a release agent containing silicone as a main component, such as methylhydroxypolysiloxane, methylhydropolysiloxane, polydimethylsiloxane, etc., and is used as it is, or It is dissolved in a solvent and used as a release agent coating liquid. Here, the “main component” refers to a main component constituting the silicone-based release agent, which means that it has a significant effect on the properties of the composition, and includes a case where the whole consists only of the main component. It is.

The mirror surface of the cleaning blade is
By doing so, the edge accuracy becomes good,
In addition, low friction is promoted.
It is not clear at all. However, for the following reasons
It is assumed that That is, the mold surface (mold mirror surface)
Cleaning blade coated with cone release agent
Cast the polyurethane resin composition into the mold
The cured polyurethane resin composition obtained by
For the surface (mirror surface) of the cleaning blade
When surface modification treatment (oxygenation treatment) such as corona discharge is performed,
Silicon present on the mirror surface of the cleaning blade
The release agent is oxidized, and silica (SiO _Two) (Glass
Tones). At this time, silicon atoms (Si) are
By performing the oxygenation treatment so as to be present in an amount of at least m%,
Edge accuracy is improved and low friction is improved.
it is considered as. Note that the above release agent is
Silicon coated on the mold surface (mold mirror surface) of the molding die
The mold release agent has migrated.

According to the present invention, since only the mirror surface 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 improved. Does not drop. Further, in the cleaning blade of the present invention, the silicone-based release agent on the mirror surface is considered to exhibit adhesion by increasing the polarity of the silicone and the polyurethane resin by the oxygenation treatment. Thus, the adhesion between the silicone-based release agent and the cured polyurethane resin composition 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) are present at 8 atom% or more on the mirror surface of the cleaning blade. Here, the silicon atom (Si) occurs more than 8 atom%, the total atomic (target elements present in the mirror surface of the cleaning blade: ³ Li~ ⁹⁸
The proportion of silicon atoms (Si) in Cf) is 8 atom%.
This is referred to as X-ray photoelectron spectroscopy [E
SCA] means that the value derived by analyzing the surface is 8 atom% or more.

In particular, the number of oxygen atoms (O) on the surface of the mirror surface
When the ratio (O / C) between the number of carbon atoms (C) and the O / C ratio inside the cleaning blade is set to 1.6 times or more, the friction coefficient 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.

In the above description, the silicone release agent applied in the cleaning blade mold is transferred and adhered to the formed cleaning blade during molding. , A silicone-based release agent, after molding, on the formed cleaning blade,
You may make it adhere by dipping, spray application, etc.

[0017]

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

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

[0022]

(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, isosebacic acid, or the like. 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. Next, the polyurethane resin composition solution obtained by blending and mixing the above-mentioned main agent liquid and curing agent liquid at a predetermined ratio is placed in a cleaning blade molding die (mold surface) holding the plate-like holder 2. Is mirror-finished) and is cured by reaction. Then, the obtained cured product is removed from the molding die, and the mirror surface is subjected to an oxygenation treatment described later, so that the silicon atoms (Si) on the surface have a specific ratio as shown in FIG. A cleaning blade 1 having an existing mirror surface 3 can be obtained. The cleaning blade 1 is formed integrally with the plate-shaped holder 2.

The cleaning blade molding die is
It is desirable that preheating is performed before the polyurethane resin composition solution is injected. That is, the moldability is improved by preheating the mold. The silicone-based release agent described below is applied in advance to the inner peripheral surface (mold mirror surface) of the cleaning blade molding die.

The silicone release agent is not particularly restricted but includes, for example, those containing methylhydroxypolysiloxane, methylhydropolysiloxane, polydimethylsiloxane or the like as a main component. These may be used alone or in combination of two or more. Among them, a silicone-based release agent containing polydimethylsiloxane as a main component is preferable because it is preferable as a release agent and can favorably reduce friction after the oxygenation treatment.

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

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.

[0040]

(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 above 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 1 becomes too high, which damages the photosensitive drum and tends to cause image defects.

The polyurethane resin composition solution thus obtained is injected into the mold and heated.
Reacts and cures to form a cleaning blade.

The obtained cleaning blade is taken out of the mold and its mirror surface is subjected to an oxygenation treatment.
As the oxygenation treatment, one of corona discharge treatment, plasma discharge treatment, and ozone atmosphere treatment is performed. As the corona discharge treatment, for example, a high-frequency power supply (AGI-020S, manufactured by Kasuga Electric) is used, and the
This is performed by generating a corona discharge with an output of kW and discharging at a distance of 3 mm from the electrode and an angle of 15 degrees for 60 seconds. In addition, the plasma discharge treatment is performed, for example, by repeating a discharge treatment of moving at a distance of 50 mm and 20 mm / sec 20 times using a plasma jet treatment apparatus (PJ-1, manufactured by Kasuga Electric). The ozone atmosphere treatment is performed by, for example, performing a treatment for 24 hours in an atmosphere having an ozone concentration of 50 pphm and a temperature of 40 ° C. using a UVC ozone aging tester (PPHM UVC-D, manufactured by Toyo Seiki Seisaku-sho, Ltd.). Will be

On the mirror surface of the cleaning blade of the present invention thus obtained, 8a of silicon atoms (Si)
tom% or more. More preferably, 10 to 19
atom% range. That is, a silicon atom (Si)
Is less than 8 atom%, the effect 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 surface of the mirror surface formed by the oxygenation treatment is determined by the O / C ratio inside the cleaning blade.
When the ratio is set to 1.6 times or more, the friction coefficient can be further reduced. More preferably, it is in the range of 1.6 to 4.5 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 Release Agent] On the other hand, polydimethylsiloxane [SH200 oil (500 mm
² / s, 25 ° C.), manufactured by Dow Corning Toray Silicone Co., Ltd.] in an isoparaffin-based hydrocarbon solution (IP Solvent 1620, manufactured by Idemitsu Petrochemical Co., Ltd.) to a concentration of 2% by weight.

[Formation of cleaning blade]
As shown in FIG. 2A, the inner peripheral surface (mirror surface) 5a of the cleaning blade molding die 5 preheated to 140 ° C.
After spraying the above-mentioned release agent to the coating amount of 1.2 g / mm ^{2 with} a spray, the plate-like holder 2 having a surface subjected to an adhesive treatment (application of an adhesive) with a cleaning blade, After being mounted on the mold 5, the polyurethane resin composition solution was poured into the mold 5, reacted at 140 ° C. for 30 minutes to cure, and the polyurethane resin composition cured product 4 was cured.
I got Then, as shown in FIG. 2 (B), after the cured body 4 is cut at the position indicated by the broken line X after the mold release,
After a secondary cure of × 10 hours, two cleaning blades (thickness: 2 mm × longitudinal direction: 240 mm × width direction: 10 mm)
mm).

[Oxygenation Treatment] The mirror surface of the cleaning blade was subjected to 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]

Comparative Example 1 The same as Example 1 except that a synthetic wax-based release agent (UR-130conc, manufactured by Konishi Co., Ltd.) containing no silicon atom (Si) was used without dilution as a release agent. Thus, a cleaning blade was produced. Note that the mirror surface was not subjected to oxygenation treatment.

[0056]

Comparative Example 2 The same as in Example 1 except that a synthetic wax-based release agent containing no silicon atom (Si) (UR-130conc, manufactured by Konishi) was used as a release agent without diluting it in a solvent. Thus, a cleaning blade was produced. The oxygenation treatment for the mirror surface was performed by corona treatment under the same conditions as in Example 1.

[0057]

Comparative Example 3 A cleaning blade was produced in the same manner as in Example 1, except that the mirror surface 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] The ESCA system (PH) was applied to the mirror surface of each cleaning blade and the inside of the cleaning blade.
Using an I5600 system (manufactured by ULVAC-PHI), the proportions of oxygen atoms, carbon atoms, nitrogen atoms and silicon atoms were measured under the following measurement conditions, and the silicon atomic weight (S
i) and O / C ratio were calculated. That is, while irradiating X-rays using an Al monochromator (14 kV, 150 W) and performing charge correction with an electron neutralizing gun, a measurement area: 800 μm, a photoelectron extraction angle: 45 deg, a resolution of 187.85 passage energy, 0.8 eV /
The measurement was performed under the conditions of step 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 bonding the plate-like holding material 12 to one end, the other end corner is pressed against the surface of the smooth PET plate-like body 16,
Move the PET plate 16 in the direction of arrow Y (in the direction of the wiper).
At a constant speed, 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.

[0062]

(Equation 3)

The change in edge linearity before and after the 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 ×.

[0064]

[Table 1]

[0065]

[Table 2]

From the results shown in Tables 1 and 2, it can be seen that all of the products of the examples are cleaning blades having a small amount of wear and 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.

In the above embodiment, a mold for molding a pair of cleaning blades is used as a mold for molding a cleaning blade. However, a mold for molding one cleaning blade may be used. At this time, the obtained plate-shaped cleaning blade has not only the plate surface (front surface) but also the end surface between the plate surfaces [FIG.
Corresponding to the broken line X] is also a mirror surface. Therefore, the processing of the present invention described above is also applied here.

[0068]

As described above, in the cleaning blade of the present invention, a part of the surface of the plate is formed into a mirror surface,
At least 8 atom% of silicon atoms (Si) are present on the surface of the mirror surface in such a manner that adhesion of the silicone-based release agent is increased by adhesion of the silicone-based release agent and oxygenation treatment. Further, the silicone-based release agent is changed into a silica state by the oxygenation treatment. Therefore, the edge accuracy is improved, and the low friction property is improved. The ratio (O / C) between the number of oxygen atoms (O) and the number of carbon atoms (C) on the surface of the mirror surface is determined by the O / C ratio inside the cleaning blade.
When the ratio is set to 1.6 times or more, the coefficient of friction 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 Mirror 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. F term (reference) 2H034 BF03 BF05 3B116 AA18 AB53 BA03 4F202 AA42 AB03 AD08 AD11 AH33 CA01 CB01 CB12 CM46 CM83 4F204 AA42 AB03 AD08 AD11 AH33 EA03 EB01 EB12 EF27 EW23 EW05 EW05

Claims (5)

[Claims] 1. A plate-like cleaning blade made of a cured polyurethane resin composition, wherein a part of the surface of the plate-like member is formed into a mirror surface, and a silicone-based release agent is adhered to the mirror surface. By oxygenation, silicon atoms (S
a cleaning blade wherein i) is present in an amount of 8 atom% or more. 2. The adhesion of the silicone-based release agent to the mirror surface is achieved by transferring the silicone-based release agent applied to the mirror surface of the mold for the cleaning blade to the cleaning blade during molding of the cleaning blade. 2. The cleaning blade according to claim 1, wherein the cleaning is performed. 3. The cleaning blade according to claim 1, wherein the oxygenation treatment is one of a corona discharge treatment, a plasma discharge treatment, and an ozone atmosphere treatment. 4. The ratio (O / C) of the number of oxygen atoms (O) to the number of carbon atoms (C) on the surface of the mirror surface is 1.6 times or more the O / C ratio inside the cleaning blade. The cleaning blade according to claim 1, wherein the cleaning blade is set. 5. The cleaning blade according to claim 1, wherein the silicone-based release agent contains polydimethylsiloxane as a main component.