JP5510962B2 - Blade member - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade member, and more particularly, a cleaning blade that removes toner on a toner image carrier that forms a toner image such as a photoreceptor or a transfer belt in electrophotography and then transfers the toner image to a transfer material. The present invention relates to a blade member suitable for use as a member and a squeegee for printing.

  In general, in an electrophotographic process, a cleaning blade for removing toner is used in order to repeatedly use an electrophotographic photosensitive member or a transfer belt. Since the cleaning blade is in contact with the photoconductor for a long period of time, it is required to have good wear resistance. Further, there is a problem that abnormal noise such as buzzing or cueing, that is, a so-called squealing phenomenon occurs due to vibration caused by friction with the photosensitive member when contacting the photosensitive member.

  For this reason, various investigations have been made as countermeasures against conventional noise. For example, a cleaning blade (see Patent Document 1) or a rubber made by laminating a plurality of layers of materials having different characteristics along the thickness direction, and the material constituting the layer on the cleaning edge side is a high-hardness resin A cleaning blade comprising a thermosetting elastomer composition containing a component (A), a filler (B), and a crosslinking agent (C), and suppressing noise by adjusting the filler (B) and the crosslinking agent (C) (See Patent Document 2) and the like.

  Conventional blades have problems such as many manufacturing steps and high costs, and insufficient blade characteristics.

  Furthermore, in recent years, as the unit has a long life, the photoconductor has become highly durable, and accordingly, the blade is also required to have high durability.

JP 2004-184462 A JP 2007-41454 A

  In view of such circumstances, it is an object of the present invention to provide a highly durable blade member that prevents squealing.

  A first aspect of the present invention that solves the above-described problem is a blade member that is used in contact with a contacted body, an edge layer that contacts the contacted body, and a back surface provided on the back surface of the edge layer The edge layer comprises a polyurethane member obtained by curing and molding a polyurethane composition containing at least a polyol, an isocyanate compound, and a crosslinking agent, and the back layer comprises a polyol, an isocyanate compound, And a polyurethane member formed by blending 1 to 30 parts by weight of an inorganic filler having a specific gravity of 2.0 or more and a thin plate shape and an aspect ratio of 3 or more with respect to 100 parts by weight of the polyurethane composition containing at least a crosslinking agent. The blade member is characterized by the above.

According to a second aspect of the present invention, in the blade member according to the first aspect, the blade member has a storage elastic modulus (1 Hz) at 40 ° C. of 2.0 × 10 ⁷ Pa or more. Located on the blade member.

  According to a third aspect of the present invention, there is provided the blade member according to the first or second aspect, wherein the inorganic filler is mica or wollastonite.

  According to a fourth aspect of the present invention, in the blade member according to any one of the first to third aspects, the blade member has a storage elastic modulus (1 Hz) of 10 ° C. (G′10) Pa, 50 ° C. (G'10) / (G'50) when the storage elastic modulus (1 Hz) of (G'50) Pa is (G'50) Pa is 3 or less.

According to a fifth aspect of the present invention, in the blade member according to any one of the first to fourth aspects, the rebound resilience at 10 ° C. and 50 ° C. of the polyurethane member of the back layer is Rb _mT10 and Rb _mT50 , respectively. ΔRb _m (%) expressed by the following formula, and the rebound resilience at 10 ° C. and 50 ° C. of the elastic body obtained by curing and molding only the polyurethane composition of the back layer is Rb _nT10 and Rb _nT50 , respectively. ΔRb _n (%) represented by the following formula is in a blade member characterized by satisfying a relationship of 100 (ΔRbm−ΔRbn) / ΔRbn ≧ 14.

  The blade member of the present invention is composed of two layers of an edge layer and a back layer, and the back layer prevents squealing by blending a predetermined amount of an inorganic filler having an aspect ratio of 3 or more with respect to the polyurethane composition. Furthermore, there is an effect that a highly durable blade member having excellent wear resistance can be provided.

It is a figure which shows the measuring method of a settling rate.

  The blade member of the present invention comprises two layers, an edge layer and a back layer. The back layer has a specific amount of inorganic filler having a specific gravity of 2.0 or more, a thin plate shape, and an aspect ratio of 3 or more with respect to the polyurethane composition. By blending, it prevents squealing and has excellent wear resistance. This is because wear due to vibration can be prevented by blending the inorganic filler. Further, the inorganic filler suppresses the slip motion, or no filming occurs.

  In the blade member of the present invention, the edge layer is a layer in contact with the contacted body, and is made of a polyurethane member obtained by curing and molding a polyurethane composition containing a polyol, a polyisocyanate, and a crosslinking agent. On the other hand, the back layer is a layer provided on the back surface of the edge layer, and has a specific gravity of 2.0 or more and a thin plate-like aspect ratio with respect to 100 parts by mass of the polyurethane composition containing at least a polyol, an isocyanate compound, and a crosslinking agent. Is made of a polyurethane member formed by blending 1 to 30 parts by mass of 3 or more inorganic fillers. With this configuration, the blade layer can be prevented from squealing and wear resistance can be improved by the back layer while maintaining the properties such as the mechanical strength of the edge layer. That is, for example, squealing can be prevented and high durability can be achieved while maintaining desired blade characteristics such as cleaning characteristics. In the present invention, since a predetermined amount of the inorganic filler is blended only in the back layer, the contacted object is not damaged or the film is not peeled off, the squeal is prevented, and the wear resistance is excellent. Things can be realized.

  The edge layer is made of a polyurethane member obtained by curing and molding a polyurethane composition containing a polyol, a polyisocyanate, and a crosslinking agent. Details will be described later, but by adjusting the types and blends of polyols, polyisocyanates, and cross-linking agents, mechanical strength such as elongation at break and tensile strength is high, high hardness and excellent wear resistance. Is preferred.

  The back layer contains 1 to 30 parts by weight of an inorganic filler having a specific gravity of 2.0 or more and an aspect ratio of 3 or more, preferably 100 parts by weight of a polyurethane composition containing at least a polyol, an isocyanate compound, and a crosslinking agent. Is a polyurethane member formed by blending 5 to 15 parts by mass. Thereby, a blade member prevents a squeal and becomes the thing excellent in abrasion resistance. In addition, the blade member does not generate filming because the inorganic filler suppresses the slip motion. In addition, the effect by an inorganic filler cannot fully be acquired as the compounding quantity of an inorganic filler is less than 1 mass part, and when the compounding quantity of an inorganic filler becomes more than 30 mass parts, a urethane bond amount will reduce. As a result, the anti-sag property decreases, and the linear pressure decreases with time, or the hardness increases remarkably.

  Here, the inorganic filler has a specific gravity of 2.0 or more, a thin plate shape and an aspect ratio of 3 or more, and preferably an aspect ratio of 3 to 20. The specific gravity of the inorganic filler may be 2.0 or more, and examples thereof include 2.0 to 4.0. Here, the thin plate shape means a plate shape such as a flake shape and includes a layered compound. The shape of the inorganic filler when viewed in plan is not particularly limited, and it is sufficient that the aspect ratio is 3 or more. The aspect ratio refers to the long dimension / short dimension excluding the thickness. In addition, even if it mix | blends the inorganic filler whose specific gravity is less than 2.0 or / and aspect ratio is less than 3, the effect which prevents a squeal is not acquired. Examples of inorganic fillers having a specific gravity of 2.0 or more, a thin plate shape, and an aspect ratio of 3 or more include mica, wollastonite, quartz and the like, and the function can be easily adjusted by changing the flake diameter, specific gravity, and aspect ratio. Mica is particularly preferable.

  In the blade member of the present invention, a predetermined inorganic filler is blended in the back layer, and no inorganic filler is blended in the edge layer. Thereby, a blade member does not damage a to-be-contacted body or generate | occur | produce peeling of a film | membrane. The blade member does not contain an inorganic filler in the edge layer, and the ratio of the area where the inorganic filler is present in the entire thickness direction may be 10 to 98%, preferably 50 to 90%. In addition, if the ratio of the area where the inorganic filler is present in the entire thickness direction of the blade member is less than 10%, the effect of preventing the squealing by the inorganic filler is not sufficiently exhibited. There is a risk of it. The inorganic filler may be present in any region of the back layer, for example, the surface of the back layer opposite to the contact surface of the blade member, that is, in a state biased to the so-called back side, You may exist in the state disperse | distributed uniformly to the whole back layer.

The ratio of the thickness of the edge layer and the back layer is not particularly limited, but it is preferable that the thickness of the edge layer / the thickness of the back layer be 0.05 to 3.

The blade member of the present invention includes a back layer in which a predetermined amount of an inorganic filler is blended with the polyurethane composition, so that the storage elastic modulus is increased. The storage elastic modulus can be used as an index of the vibration capability of the blade member, and the blade member having a high storage elastic modulus has a high ability to attenuate the vibration transmitted from the urethane bond. Since the blade member of the present invention has a higher storage elastic modulus than the conventional blade member, it is excellent in preventing squealing and preventing filming of toner and external additives. The blade member preferably has a storage elastic modulus (1 Hz) at 40 ° C. of 1.0 × 10 ⁷ Pa or more, more preferably 2.0 × 10 ⁷ Pa or more, and particularly 3.0 × 10 ⁷ Pa. It is preferable that it is Pa or more. The blade member that satisfies this condition is prevented from squeaking even under more severe conditions.

  The blade member has a storage elastic modulus (1 Hz) at 10 ° C. of (G′10) Pa and a storage elastic modulus (1 Hz) at 50 ° C. of (G ′ 50) Pa. G′50) is preferably 3 or less. This is because when the ratio is 3 or less, the environment dependency is small, and even when the environment changes, a sufficiently stable cleaning property can be maintained.

In addition, the back layer according to the present invention has a temperature dependency that is reduced due to the blending of a predetermined amount of the inorganic filler, and the mechanical properties and the like are stabilized even when the environment changes. The polyurethane member of the back layer is, for example, ΔRbm (%) represented by the following formula when the rebound resilience of the polyurethane member at 10 ° C. and 50 ° C. is Rbm _T10 and Rbm _T50 , respectively, and the polyurethane composition of the back layer only ΔRbn (%) represented by the following formulas when the rebound resilience at 10 ° C. and 50 ° C. of the elastic body cured and molded from Rbn _T10 and Rbn _T50 is 100 (ΔRbm−ΔRbn) / ΔRbn ≧ 14 It will satisfy the relationship.

  It is preferable that the back layer has a set rate of 7.0% or less. Here, the set rate is obtained by the following method. The back layer may be molded by selecting a polyurethane composition excellent in set resistance. By providing the back layer having a settling rate of 7.0% or less, the blade member has excellent settling resistance. The settling rate of the blade member is preferably less than 10%.

As shown in FIG. 1A, a blade having a holder member 20A fixed to a test sample 10 (back layer or blade member) is attached to a pressing base 30, an initial set angle θ is 25 °, and a biting amount y is 1 Press at 7 mm, leave in a standing environment (temperature 45 ° C. × humidity 95%) for 72 hours, take out from the standing environment, leave in a deformed state for 6 hours, and leave at room temperature for 30 minutes after releasing from the pressing base 30. Thereafter, as shown in FIG. 1B, the holder member 20A is fixed to the fixing jig 40, the amount of collapse h is measured by a pick tester using a height gauge, and compared with the amount of collapse h ₀ before the test. The amount (h ₀ -h) is obtained, and the settling rate is obtained from the following equation.

  The polyurethane composition for the back layer is obtained by mixing a polyol and polyisocyanate with a crosslinking agent or the like.

  Examples of the polyol include polyester polyol obtained by dehydration condensation of diol and dibasic acid, polycarbonate polyol obtained by reaction of diol and alkyl carbonate, caprolactone-based polyol, polyether polyol, and the like. Polytetramethylene ether Glycol (PTMG) is preferred. The polyol may be used alone or in combination of two or more. The polyol preferably has a molecular weight of 1000 to 3000. When polytetramethylene ether glycol (PTMG) having a molecular weight of 1000 to 1500 is used, the storage elastic modulus can be increased relatively easily.

  The polyisocyanate to be reacted with the polyol preferably has a relatively non-rigid molecular structure. For example, 4,4′-diphenylmethane diisocyanate (MDI), 2,6-toluene diisocyanate (TDI), 1,6-hexane Examples thereof include diisocyanate (HDI), 1,5-naphthalene diisocyanate (NDI), and 3,3-dimethylphenyl-4,4-diisocyanate (TODI). Particularly preferred is MDI. Polyisocyanate may be used alone or in combination of two or more. The blending ratio of the polyisocyanate is preferably 30 to 80% by mass in the polyurethane. This is because if it is less than 30% by mass, the tensile strength may be insufficient, and if it exceeds 80% by mass, the permanent elongation becomes too large.

  Examples of the crosslinking agent include diol (bifunctional), triol (trifunctional), tetraol (tetrafunctional), and the like. Of course, these may be used in combination. An amine compound may be used as a crosslinking agent.

  The diol is not particularly limited, and examples thereof include propanediol (PD) and butanediol (BD). The triol is not particularly limited, but a triol having a molecular weight of 120 to 2500 is preferable, and a triol having a molecular weight of 120 to 1000 is more preferable. Specifically, it is synthesized from a short-chain triol such as trimethylolethane (TME) or trimethylolpropane (TMP), or a caprolactone triol (ε caprolactone) represented by the following formula (1) having a molecular weight larger than those. Triol) and the like. Triol is added to improve characteristics such as creep and stress relaxation.

  The blending ratio of the crosslinking agent is not particularly limited, but the ratio of the trifunctional crosslinking agent in the crosslinking agent is preferably 0 to 60%, more preferably 5 to 40%. Two or more types of bifunctional crosslinking agents and trifunctional crosslinking agents may be mixed and used.

  The polyurethane composition of the edge layer is obtained by blending a polyol and polyisocyanate with a crosslinking agent or the like. As the polyol, polyisocyanate, and cross-linking agent, the same materials as those described for the back layer can be used.

  Further, it is preferable that the polyurethane member of the edge layer and the polyurethane member of the back layer have an α value of 0.7 to 1.0. The α value is a value represented by the following formula. If the α value is larger than 1.0, the functional group (hydroxyl group, amino group, etc.) of the crosslinking agent remains, so that the contacting photoreceptor is contaminated, and if it is less than 0.7, the crosslinking density is too small and the strength is low. In some cases, it may become insufficient, or it may take time to deactivate the residual isocyanate, which may contaminate the photoreceptor.

  The edge layer and the back layer according to the present invention are blended with the above-described polyol by adjusting the polyisocyanate part by mass, the mass part and the ratio of the crosslinking agent, and in the case of the back layer, a predetermined amount of inorganic filler is further added. It can manufacture by mix | blending and making these react.

  It is preferable that the edge layer in contact with the contacted body has a high hardness and the back layer provided on the back surface of the edge layer has a lower hardness than the edge layer. Specifically, the hardness of the edge layer is JIS A. It is preferable that the hardness of 70-90 degrees and a back layer is 60-80 degrees by JISA. The edge layer in contact with the contacted body has a high hardness, and the back layer provided on the back surface of the edge layer has a lower hardness than the edge layer, so that it has high durability and excellent wear resistance. It becomes a blade member.

  The blade member according to the present invention can use a general method for producing polyurethane such as a prepolymer method or a one-shot method, but is preferably formed by centrifugal molding. This is because the dispersion state of the inorganic filler in the back layer can be easily adjusted by controlling the rotational speed of the rotary drum of the centrifugal molding machine. Moreover, it is because an edge layer and a back layer can be shape | molded integrally.

  In the case of manufacturing by the centrifugal molding method, first, the molding material of the edge layer and the back layer is sequentially added and molded while rotating the rotary drum of the centrifugal molding machine at a predetermined rotational speed. For example, the material of the back layer is first put into the drum, and after forming the back layer, the material of the edge layer is put, and the edge layer is formed on the back layer. At this time, it is preferable to introduce the material of the layer to be molded next before the layer to be molded first is not completely cured. Thereby, a two-layer can be shape | molded integrally. In addition, since the air surface, that is, the surface of the layer to be molded later is flatter than the mold surface, it is desirable to use the air surface so that it is in contact with the member to be charged.

  However, the method of forming the blade member is not limited to this. For example, the edge layer is formed by casting separately on the back layer formed by casting, or the edge is formed by dipping or spraying. Examples include a method of forming a layer.

  The polyurethane produced in this manner is cut or the like to form a blade member of a predetermined size, and this is bonded to the support member with an adhesive or the like to form a blade.

  In the blade member of the present invention, as described above, the edge layer has high mechanical strength such as elongation at break and tensile strength, high hardness and excellent wear resistance, and the back layer prevents noise and wear resistance. By making it excellent in performance, it becomes highly durable with squealing while maintaining desired blade characteristics.

The blade member of the present invention is suitable for use as an electrophotographic photosensitive member, a transfer drum and transfer belt used in a transfer process, or a cleaning blade member used for cleaning an intermediate conveyance belt, but is not limited thereto. For example, it is suitable for use in toner regulating blades, metallic cleaning rolls, and the like.

  Hereinafter, although the blade member of this invention is demonstrated based on an Example, this invention is not limited to this.

<Polyurethane A>
100 parts by mass of 1,9ND adipate having a molecular weight of 2000 obtained from 1,9-nonanediol and adipic acid, 40 parts by mass of 4,4′-diphenylmethane diisocyanate (MDI), and 1,4-butanediol / trimethyl as a crosslinking agent The methylolpropane mixed solution (molar ratio: 85/15) was 8.1 parts by mass to obtain a polyurethane composition.

<Polyurethane a>
100 parts by mass of 1,9ND adipate having a molecular weight of 2000 obtained from 1,9-nonanediol and adipic acid, 40 parts by mass of 4,4′-diphenylmethane diisocyanate (MDI), and 1,4-butanediol / trimethyl as a crosslinking agent To a polyurethane composition having 8.1 parts by mass of a methylolpropane mixed solution (molar ratio: 85/15), 1 part by mass of mica (clarite mica; specific gravity 2.85, aspect ratio 20, manufactured by Kuraray Co., Ltd.) Blended.

<Polyurethane b>
The same as polyurethane a, except that the clarite mica was changed to 5 parts by mass.

<Polyurethane c>
The same as polyurethane a except that the clarite mica was changed to 15 parts by mass.

<Polyurethane d>
The same as polyurethane a except that the clarite mica was changed to 30 parts by mass.

<Polyurethane e>
The same as polyurethane a, except that clalite mica was changed to 0.5 parts by mass.

<Polyurethane f>
The same as polyurethane a, except that the mass of clalite mica was changed to 33 parts by mass.

<Polyurethane g>
Polyurethane a was the same as polyurethane a except that wollastonite (NYAD400; specific gravity 2.90, aspect ratio 3.0, manufactured by NYCO) was used instead of clalite mica.

<Polyurethane h>
Instead of clalite mica, it was the same as polyurethane a except that the titanium carbide (Ti9100; specific gravity 3.90, aspect ratio 1.1, manufactured by NYCO) was 10 parts by mass.

<Polyurethane i>
Instead of clalite mica, it was the same as polyurethane a, except that 30 parts by mass of aluminum silicate (Delite 43B; specific gravity 1.60, aspect ratio 14, LAVIOSA CHIMICA MINARIA SpA) was used.

(Test Example 1)
A polyurethane member test sample formed by curing and molding polyurethane A and a to i is formed. The test sample made of each polyurethane has a rubber hardness of JIS K6301, and a Young's modulus at 23 ° C. is increased by 25% according to JIS K6254. According to JIS K6251, the tensile strength at 100% elongation (100% Modulus), tensile strength, and elongation at break (breaking elongation) are measured according to JIS K6251, and the permanent elongation is measured according to JIS K6262. did. Further, the impact resilience (Rb) of 10 ° C. to 50 ° C. was measured by a Lüpke-type rebound resilience test apparatus based on JIS K6255, and the temperature dependence was also evaluated. The measurement results for each polyurethane are shown in Table 1.

Example 1
Polyurethane a and polyurethane A are sequentially put into a centrifugal molding machine and then subjected to centrifugal molding, whereby an edge layer made of a polyurethane member having a thickness of 0.2 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane a. A blade member comprising a back layer made of a 1.8 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form the blade of Example 1. The ratio of the mica existing area in the entire thickness direction of the blade member was 89%.

(Example 2)
Polyurethane b and polyurethane A are sequentially put into a centrifugal molding machine and subjected to centrifugal molding, whereby an edge layer composed of a polyurethane member having a thickness of 0.2 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane b. A blade member comprising a back layer made of a 1.8 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form the blade of Example 2. The ratio of the mica existing area in the entire thickness direction of the blade member was 89%.

(Example 3)
Polyurethane c and polyurethane A are sequentially put into a centrifugal molding machine and subjected to centrifugal molding, whereby an edge layer composed of a polyurethane member having a thickness of 0.5 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane c. A blade member comprising a back layer made of a 1.5 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form the blade of Example 3. The ratio of the mica existing area in the entire thickness direction of the blade member was 67%.

(Example 4)
Polyurethane d and polyurethane A are sequentially put into a centrifugal molding machine and subjected to centrifugal molding, whereby an edge layer composed of a polyurethane member having a thickness of 0.6 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane d. A blade member comprising a back layer made of a 1.4 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form the blade of Example 4. The ratio of the mica existing area in the entire thickness direction of the blade member was 57%.

(Example 5)
By sequentially putting polyurethane g and polyurethane A into a centrifugal molding machine and performing centrifugal molding, an edge layer composed of a polyurethane member having a thickness of 0.5 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane g. A blade member comprising a back layer made of a 1.5 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form the blade of Example 5. The ratio of the wollastonite existing area in the entire thickness direction of the blade member was 67%.

(Comparative Example 1)
By putting polyurethane A into a centrifugal molding machine and performing centrifugal molding, a blade member made of a polyurethane member having a thickness of 2.0 mm obtained by curing and molding polyurethane A was molded. This was bonded to a sheet metal (support member) to form a blade of Comparative Example 1.

(Comparative Example 2)
By sequentially putting polyurethane e and polyurethane A into a centrifugal molding machine and performing centrifugal molding, an edge layer composed of a polyurethane member having a thickness of 0.2 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane e. A blade member comprising a back layer made of a 1.8 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form a blade of Comparative Example 2. The ratio of the area where mica exists in the entire thickness direction of the blade member was 89%.

(Comparative Example 3)
Polyurethane f and polyurethane A are sequentially put into a centrifugal molding machine and centrifugally molded, whereby an edge layer composed of a polyurethane member having a thickness of 0.2 mm obtained by curing and molding polyurethane A, and a thickness obtained by curing and molding polyurethane f. A blade member comprising a back layer made of a 1.8 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form a blade of Comparative Example 3. The ratio of the area where mica exists in the entire thickness direction of the blade member was 89%.

(Comparative Example 4)
Polyurethane h and polyurethane A are sequentially put into a centrifugal molding machine and centrifugally molded, whereby an edge layer made of a polyurethane member having a thickness of 0.5 mm, which is cured and molded of polyurethane A, and a thickness of cured and molded polyurethane h A blade member comprising a back layer made of a 1.5 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form a blade of Comparative Example 4. The ratio of the titanium carbide existing region in the entire thickness direction of the blade member was 67%.

(Comparative Example 5)
By sequentially putting polyurethane i and polyurethane A into a centrifugal molding machine and performing centrifugal molding, an edge layer composed of a polyurethane member having a thickness of 0.2 mm, which is cured and molded of polyurethane A, and a thickness of cured and molded polyurethane i A blade member comprising a back layer made of a 1.8 mm polyurethane member was molded. This was adhered to a sheet metal (support member) to form a blade of Comparative Example 5. The ratio of the existing area of aluminum silicate in the entire thickness direction of the blade member was 89%.

(Test Example 2)
A test sample of a polyurethane member obtained by curing and molding the polyurethane composition used for the back layer with the blade member of each example and each comparative example was prepared, and the rebound resilience (Rb) was a Lupke-type rebound resilience test apparatus based on JIS K6255. And measured at 10 ° C. and 50 ° C., and the temperature dependence of the back layer of the blade member of each example and each comparative example was evaluated.

  Further, the storage elastic modulus (1 Hz) of the blade member at 10 ° C., 40 ° C. and 50 ° C. was measured by EXSTAR6000 (manufactured by SII). The results are shown in Tables 2 and 3.

(Test Example 3)
The blade member of each example and each comparative example was attached to an actual machine (manufactured by Konica Minolta Business Technologies, Inc .: magiccolor 5430) as a cleaning blade, and in a temperature 30 ° C. × humidity 90% environment, a toner printing rate 5% chart, One sheet was completely operated at a linear speed of 80 mm / sec. After printing 1000 sheets, the presence or absence of squeak during printing was confirmed by hearing. The case where no squeal was confirmed was marked with ◯, and the case where squeal was confirmed was marked with x. The results are shown in Tables 2 and 3. The amount of wear of the blade used in this test was confirmed with a microscope. The results are shown in Tables 2 and 3.

(Test Example 4)
The holder member 20A is fixed to the blade member test sample 10 of each example and each comparative example, and is attached to the pressing base 30 so that the amount of biting is 1.7 mm and the initial set angle is 25 deg. 1 (a)). It was left for 72 hours in a standing environment (temperature 45 ° C. × humidity 95%), further removed from the standing environment, left in a deformed state for 6 hours, and left at room temperature for 30 minutes after being released from the pressing base 30. Thereafter, as shown in FIG. 1 (b), the holder member 20A was fixed to the fixing jig 40, the amount of collapse h was measured with a pick tester using a height gauge, and the settling rate was obtained. The sag resistance was evaluated with a sag rate of less than 10% and a sag rate of 10% or more as x. The results are shown in Tables 2 and 3.

(Summary of results)
In all of the blade members of Examples 1 to 5, the storage elastic modulus (1 Hz) at 40 ° C. is 2.1 × 10 ⁷ Pa or more, and (G′10) / (G′50) is 1.23 or less. Yes, and 100 (ΔRbm−ΔRbn) / ΔRbn ≧ 15. These blade members were excellent in set resistance and wear resistance without generating squeal.

On the other hand, the blade member of Comparative Example 1 consisting only of a polyurethane member not blended with an inorganic filler was excellent in anti-sag property, but had a storage elastic modulus (1 Hz) at 40 ° C. of 0.7 × 10 ^7. Pa was low, squeal occurred, and the wear resistance was poor.

The blade member of Comparative Example 2 in which 0.5 part by mass of the inorganic filler is blended in the back layer has a storage elastic modulus (1 Hz) at 40 ° C. as low as 1.2 × 10 ⁷ Pa, squealing, and wear resistance. It was inferior to.

  The blade member of Comparative Example 3 in which 33 parts by mass of the inorganic filler was blended in the back layer had a set rate of 10% or more.

The blade member of Comparative Example 4 in which an inorganic filler having an aspect ratio of 1.1 was blended in the back layer was excellent in anti-sag property, but the storage elastic modulus (1 Hz) at 40 ° C. was 1.3 × 10 ⁷ Pa. The squeal occurred and the wear resistance was poor.

  Further, the blade member of Comparative Example 5 in which an inorganic filler having a specific gravity of 1.6 was blended in the back layer had a (G′10) / (G′50) larger than 3 and poor wear resistance. .

10 test sample 20A holder member 30 foundation for pressing 40 fixing jig

Claims (5)

A blade member used in contact with a contacted object,
It consists of two layers, an edge layer that contacts the contacted body and a back layer provided on the back surface of the edge layer,
The edge layer comprises a polyurethane member obtained by curing and molding a polyurethane composition containing at least a polyol, an isocyanate compound, and a crosslinking agent,
The back layer has an inorganic filler with a specific gravity of 2.0 or more, a thin plate shape, and an aspect ratio of 3 or more with respect to 100 parts by mass of a polyurethane composition containing at least a polyol, an isocyanate compound, and a crosslinking agent. A blade member comprising a polyurethane member formed by blending parts. The blade member according to claim 1, wherein the blade member has a storage elastic modulus (1 Hz) at 40 ° C. of 2.0 × 10 ⁷ Pa or more. The blade member according to claim 1 or 2, wherein the inorganic filler is mica or wollastonite. The blade member according to any one of claims 1 to 3, wherein the blade member has a storage elastic modulus (1 Hz) of 10 ° C (G'10) Pa and a storage elastic modulus (1 Hz) of 50 ° C ( A blade member, wherein (G′10) / (G′50) when G′50) Pa is 3 or less. The blade member according to any one of claims 1 to 4, wherein ΔRb represented by the following formula when the rebound resilience of the polyurethane member of the back layer at 10 ° C and 50 ° C is Rb _mT10 and Rb _mT50 , respectively. _m (%) and ΔRb _n (represented by the following formulas when the rebound resilience at 10 ° C. and 50 ° C. of the elastic body obtained by curing and molding only the polyurethane composition of the back layer is Rb _nT10 and Rb _nT50 , respectively. %) Satisfies a relationship of 100 (ΔRbm−ΔRbn) / ΔRbn ≧ 14.

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