Cleaning blade for electrophotography, process cartridge and electrophotographic image forming apparatus, and urethane compact

Abstract

To provide a cleaning blade that controls moisture absorption to prevent a reduction in hardness even in a high humidity environment and has excellent cleaning performance, and a process cartridge and an electrophotographic image forming apparatus having the cleaning blade.SOLUTION: A cleaning blade for electrophotography is provided with an elastic member containing polyurethane and a support member. The storage elastic modulus of the elastic member at an oscillation frequency of 1×10-3 Hz is 12.0-18.0 MPa. In pulse NMR measurement in a 50°C environment of a sample sampled from the elastic member, a segment with a spin-spin relaxation time (T2L) of 250-360 μs is present. A polyurethane elastomer has a polysiloxane segment having a specific structure. The polysiloxane segment is coupled to a polyurethane skeleton of the polyurethane elastomer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a cleaning blade, a process cartridge, an image forming apparatus, and a urethane molded article used in an electrophotographic apparatus. [Background technology]

[0002] Electrophotographic devices are equipped with cleaning members to remove toner remaining on the surfaces of image carriers such as photoreceptors or intermediate transfer members after transferring a toner image from the image carriers or intermediate transfer members to a transfer-receiving member. Hereinafter, the image carriers and intermediate transfer members will also be referred to as "receiving members." One of these cleaning members is a cleaning blade. In recent years, with the increase in the number of sheets that can be printed due to the longer life of electrophotographic devices, there has been a demand for cleaning blades that can achieve high-level cleaning performance over a long period of time. To achieve this long life, it is necessary to reduce abrasion of the photosensitive drum, which is the member to be cleaned, at the point where the cleaning blade comes into contact with the photosensitive drum. From this perspective, Patent Document 1 describes that abrasion of the photosensitive drum can be suppressed by using a soft cleaning blade whose hardness is equal to or less than a certain value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-098558 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-186366 [Patent Document 3] Japanese Patent Publication No. 2020-024375 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in recent years, toner has become more spherical and processing speeds have increased, so soft cleaning blades are more likely to cause cleaning problems. In consideration of this, it is conceivable to make the hardness of the cleaning blade low enough to reduce abrasion of the photosensitive drum, but high enough to prevent toner from slipping through. Furthermore, the elastic member that constitutes the cleaning blade is prone to a decrease in hardness due to moisture absorption in a high-humidity environment. Therefore, the hardness of the cleaning blade must be controlled as described above and must be designed to take into account the decrease in hardness due to moisture absorption. As a result, the usable hardness range is narrowed. Therefore, it is difficult to achieve both excellent cleaning performance and suppression of drum abrasion for a long life.

[0005] The present disclosure aims to provide a cleaning blade that has a long life and can stably exhibit excellent cleaning performance even in high-speed systems. Specifically, the present disclosure aims to provide a cleaning blade that is resistant to loss of hardness even in high-humidity environments due to reduced moisture absorption, and that has excellent cleaning performance. The present disclosure also provides a process cartridge having the cleaning blade, which contributes to extending the cartridge's life. The present disclosure also provides an electrophotographic image forming apparatus having the cleaning blade. The present disclosure also provides a urethane molded article that is resistant to moisture absorption and exhibits minimal change in hardness due to changes in humidity. [Means for solving the problem]

[0006] According to at least one aspect of the present disclosure, there is provided an elastic member containing polyurethane, and the elastic portion a support member for supporting the material; An electrophotographic cleaning blade that cleans the surface of a moving member to be cleaned by bringing a part of the elastic member into contact with the surface of the member to be cleaned, In a 24°C environment, the vibration frequency of the elastic member is 1×10 -3 The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurements of the sample sampled from the elastic member in a 50°C environment, the spin-spin relaxation time (T2 L ) has a segment of 250-360 μs, The polyurethane contains a polyurethane elastomer, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, the number I of structures represented by formula (1) per polysiloxane segment is 7 to 195; The cleaning blade for electrophotography is provided. TIFF2025177758000002.tif40153

[0007] According to at least one aspect of the present disclosure, there is provided a process cartridge having the electrophotographic cleaning blade and a member to be cleaned. According to at least one aspect of the present disclosure, there is also provided an electrophotographic image forming apparatus having the electrophotographic cleaning blade and a member to be cleaned.

[0008] According to at least one aspect of the present disclosure, there is provided a polyurethane-containing urethane molded article, In a 24°C environment, the vibration frequency of the polyurethane is 1×10 -3 The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurements of a sample taken from the urethane molded body at 50°C, the spin-spin relaxation time (T2 L ) has a segment of 250-360 μs, The polyurethane contains a polyurethane elastomer, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, The number I of structures represented by formula (1) per polysiloxane segment is 7 to 195, and a urethane molded article is provided. TIFF2025177758000003.tif40153 [Effects of the Invention]

[0009] According to one aspect of the present disclosure, a cleaning blade can be provided that is resistant to a decrease in hardness even in a high-humidity environment due to suppressed moisture absorption and has excellent cleaning performance. Also, according to another aspect of the present disclosure, a urethane molded article can be provided that is resistant to moisture absorption and exhibits minimal change in hardness due to changes in humidity. Furthermore, according to another aspect of the present disclosure, a process cartridge and an electrophotographic image forming apparatus having the above cleaning blade can be provided. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic perspective view of an electrophotographic cleaning blade according to one embodiment of the present disclosure. [Figure 2] 10 is a diagram illustrating a state in which the edge of the cleaning blade abuts against the member to be cleaned when the process cartridge is stationary. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] In the present disclosure, unless otherwise specified, the expressions "XX or more and YY or less" or "XX to YY" representing a numerical range mean a numerical range including the endpoints, that is, the lower limit and the upper limit. When numerical ranges are stated in stages, the upper and lower limits of each numerical range can be combined in any way.

[0012] Examples of members to be cleaned that can be used with an electrophotographic cleaning blade according to one aspect of the present disclosure (hereinafter also simply referred to as a "cleaning blade") include image carriers such as photoreceptors, and endless belts such as intermediate transfer belts. Hereinafter, an embodiment of a cleaning blade according to one aspect of the present disclosure will be described in detail using an image carrier as an example of a member to be cleaned, but the present disclosure is not limited thereto. In the following description, components having the same function are denoted by the same numbers in the drawings, and their description may be omitted.

[0013] <Cleaning blade configuration> The cleaning blade includes an elastic member containing polyurethane and a support member supporting the elastic member, and cleans the surface of a moving member to be cleaned by bringing a part of the elastic member into contact with the surface of the member to be cleaned. The polyurethane contains a polyurethane elastomer.

[0014] 1 is a schematic perspective view of a cleaning blade 1 according to one embodiment of the present disclosure. The cleaning blade 1 includes an elastic member 2 and a support member 3 that supports the elastic member 2. 2 is a cross-sectional view showing a schematic example of a cleaning blade according to one embodiment of the present disclosure abutting against a member to be cleaned. The elastic member 2 has a main surface 4 facing the member to be cleaned 6 and a leading edge 5 that forms a leading edge together with the main surface 4. Reference numeral 7 indicates the direction of rotation of the member to be cleaned.

[0015] <Storage modulus> In a 24°C environment, the vibration frequency of the elastic material that makes up the cleaning blade is 1 x 10 -3 The storage modulus at Hz is 12.0 to 18.0 MPa. -3 The storage modulus at Hz can be measured by the method described below using a viscoelasticity measuring device.

[0016] Vibration frequency 1×10 -3The storage modulus at this frequency is related to the nip width. By setting this to 12.0 to 18.0 MPa, an appropriate nip can be formed, resulting in excellent cleaning performance. The vibration frequency of the elastic material is 1×10 -3 The storage modulus at Hz is 12.5 to 17.0 M The pressure is preferably 1.0 Pa, and more preferably 13.0 to 16.0 MPa.

[0017] <Moisture absorption control> The elastic member that makes up the cleaning blade is prone to a decrease in hardness due to moisture absorption in a high-humidity environment. This decrease in hardness reduces the contact pressure of the tip of the cleaning blade, causing poor cleaning. Therefore, in order to prevent poor cleaning, it is important to prevent the decrease in hardness by suppressing moisture absorption by the elastic member.

[0018] Moisture absorption can be suppressed by having a structure in which a dense cross-linked structure and a bond between polyurethane and silicone structures coexist in the elastic member. That is, the elastic member has a silicone structure within a dense cross-linked structure of polyurethane. By making the elastic member have a dense cross-linked structure, it is possible to reduce the space for moisture to penetrate. Furthermore, by bonding polyurethane and silicone structures, it is possible to reduce compatibility with moisture, thereby making it difficult for moisture to penetrate the elastic member. In this case, the dense cross-linked structure narrows the space inside the urethane, and the silicone structure bonded to the polyurethane fills this narrow space, synergistically suppressing moisture penetration and effectively suppressing moisture absorption. For example, it is preferable to have a structure in which a dense cross-linked structure and a silicone side chain structure coexist in the elastic member.

[0019] Patent Document 2 shows a structure in which a siloxane component is fixed in a urethane elastomer. On the other hand, the present disclosure has a structure in which the crosslink density of the polyurethane is increased and the polyurethane is bonded to a silicone structure, so that a more excellent moisture absorption suppression effect can be obtained than a structure in which a siloxane component is simply fixed.

[0020] <Crosslink density> The crosslink density of polyurethane is related to the spin-spin relaxation time (T2 L ) The spin-spin relaxation time is correlated with the molecular mobility of polyurethane, and the shorter the spin-spin relaxation time, the lower the molecular mobility. Low molecular mobility means a densely crosslinked structure. Therefore, the crosslink density of polyurethane can be indirectly measured by the spin-spin relaxation time.

[0021] By measuring the spin-spin relaxation time T2 (transverse relaxation time) of the blade rubber by pulsed NMR measurement, a T2 relaxation curve (free induction decay curve) can be obtained. In this disclosure, in pulsed NMR measurements of a sample sampled from an elastic member in a 50°C environment, the spin-spin relaxation time (T2 L ) but there is a segment of 250-360 μs. That is, the elastic member is formed of a polyurethane elastomer having a polyurethane segment with a spin-spin relaxation time of 250 to 360 μs.

[0022] The spin-spin relaxation time T2 is measured by the solid echo method using a pulsed NMR device. Specifically, a T2 relaxation curve is obtained in the pulsed NMR measurement. The obtained T2 relaxation curve is separated into two components according to the length of the relaxation time. More specifically, the T2 relaxation curve is separated into two components by curve fitting to the equation described below. Of the two separated components, the T2 L is the T2 relaxation time of the component with the long relaxation time, and T2 S is the T2 relaxation time of the component with a short relaxation time.

[0023] The components with long relaxation times are presumed to correspond to the soft segments of the polyurethane elastomer. The components with short relaxation times are presumed to correspond to the hard segments. In this disclosure, the hard segments refer to the aggregated crystalline components of urethane bonds, nurate bonds, polymeric MDI, trimethylolpropane, etc., at the crosslinking points and in the vicinity of the crosslinking points. It refers to a component with low molecular mobility. Soft segments refer to segments with high molecular mobility between crosslinking points. T2 using pulsed NMR equipment L A more specific measurement method will be described later.

[0024] The elastic member contains polyurethane, which may include a polyurethane elastomer composed of a hard segment and a soft segment. Spin-spin relaxation time (T2 L If the time t1 is less than 250 μs, the crosslinking density will be too high, causing the cleaning blade to lose flexibility and making the contact position with the member to be cleaned unstable. T2 L When there are segments with a T2 of 250 to 360 μs, the dense cross-linked structure can suppress moisture absorption while ensuring stable contact with the cleaning object. L If the time is 320 μs or less, it is more effective in suppressing moisture absorption, and therefore is preferable.

[0025] That is, in pulsed NMR measurements of a sample sampled from an elastic member in a 50°C environment, the spin-spin relaxation time (T2 L ) preferably has a segment of 250 to 320 μs, more preferably has a segment of 260 to 300 μs, and further preferably has a segment of 270 to 290 μs. The spin-spin relaxation time (T2 L ) can be controlled within the above range, for example, by increasing the concentration of the crosslinking agent in the raw material composition of the elastic member.

[0026] <Silicone side chain> The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1). [ka] The polysiloxane segment having the structure represented by formula (1) is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer. The number I of structures represented by formula (1) per polysiloxane segment is 7 to 195.

[0027] In the polysiloxane segment, the structures represented by formula (1) may be continuous, or other siloxane structures may be present between them. Examples of the bond between the structure represented by formula (1) and the structure containing a polyurethane skeleton include the following structures: In the following structures, R represents a hydrocarbon having 1 to 10 carbon atoms (preferably 1 to 5). The -O- on the left side is bonded to the structure represented by formula (1), and * represents the bond site with the polyurethane skeleton. [ka]

[0028] The polyurethane elastomer may have an end that is not bonded to the structure containing the polyurethane skeleton. Examples of an end that is not bonded to the structure containing the polyurethane skeleton include the following structure: -O- on the left side is bonded to the structure represented by formula (1). [ka] Furthermore, the terminal that is not bonded to the structure containing the polyurethane skeleton may have the following structure containing a hydroxyl group: In the following structure, R represents a hydrocarbon having 1 to 10 carbon atoms (preferably 1 to 5). The following structure shows the state when, for example, a silicone oil modified at both ends with carbinol is used for the polysiloxane segment, and one terminal is not bonded to the polyurethane skeleton. [ka]

[0029] By including a polysiloxane segment having the structure represented by the above formula (1) in a polyurethane elastomer having a highly crosslinked structure, moisture absorption can be suppressed.

[0030] The polyurethane elastomer preferably contains 0.5 to 15 mass % of the structure represented by the above formula (1), more preferably 0.8 to 12 mass %, and even more preferably 1 to 10 mass % of the structure represented by the above formula (1).

[0031] It is preferable that the polyurethane elastomer contains 0.5% by mass or more of the structure represented by the above formula (1), since a sufficient moisture absorption suppression effect can be obtained.Furthermore, it is preferable that the polyurethane elastomer contains 15% by mass or less of the structure represented by the above formula (1), since the ratio of the polyurethane elastomer in the elastic member can be sufficiently maintained, and the cleaning blade can obtain the drum followability and abrasion resistance required for the cleaning blade. In the above formula (1), I is an integer of 7 to 195. I is preferably an integer of 40 to 160.

[0032] The polysiloxane segment is preferably bonded to the polyurethane skeleton via a structure represented by the following formula (2). [ka] (In formula (2), n represents an integer of 1 to 5, and * represents a bonding site with the polyurethane skeleton.) The number m of structures represented by formula (2) per polysiloxane segment is preferably 1-10.

[0033] That is, it is preferable that a structure of formula (2) exists between structures of formula (1), and that the polysiloxane segment is bonded to the polyurethane skeleton via the structure of formula (2). Note that, although m=1 to 10, when a plurality of structures of formula (2) exist in the polysiloxane segment, the structures of formula (2) may exist in blocks or randomly. For example, the structures of formula (1) may be bonded to the left and right of the structure of formula (2), but the structures of formula (2) may also exist consecutively.

[0034] The -O- on the left side of the structure represented by formula (2) can be bonded to Si in the structure represented by formula (1) or the structure represented by formula (2). Si in the structure represented by formula (2) can be bonded to -O- in the structure represented by formula (1) or the structure represented by formula (2). Repeating siloxane units may be bonded to both sides of the structure represented by formula (2).

[0035] The polysiloxane segments are bonded to a structure containing a polyurethane skeleton, such as the structure shown in formula (2). This bond structure allows the polydimethylsiloxane segments to be incorporated into the crosslinked structure of the polyurethane elastomer, more effectively preventing moisture from penetrating into the polyurethane.

[0036] In the above formula (2), m is preferably 2 to 10, and n is preferably an integer of 1 to 3. Patent Document 3 discloses a urethane elastomer containing a siloxane component. On the other hand, in the present disclosure, the siloxane component is fixed in the urethane elastomer, thereby achieving a more excellent moisture absorption suppression effect.

[0037] By using the polysiloxane described below as the material for the elastic member, it is possible to obtain a polyurethane elastomer having polysiloxane segments having the structure represented by the above formula (1), in which the polysiloxane segments are bonded to a structure containing a polyurethane skeleton. As the polysiloxane, various modified silicone oils can be used, among which carbinol-modified silicone oils having a primary hydroxyl group are preferred because they have high reactivity with isocyanates (described below) and can be easily immobilized in polyurethane elastomers.

[0038] There are no particular limitations on the carbinol-modified silicone oil, and either a both-end-modified type or a side-chain-modified type can be used. For example, when a carbinol-modified silicone oil modified at both ends is used, the structure represented by formula (1) may have a structure containing a polyurethane skeleton bonded to both ends, or may have a structure containing a polyurethane skeleton bonded to only one end.

[0039] Examples of the bond between the structure represented by formula (1) and the structure containing a polyurethane skeleton include the following structures: In the following structures, R represents a hydrocarbon having 1 to 10 carbon atoms (preferably 1 to 5). The -O- on the left side is bonded to the structure represented by formula (1), and * represents the bond site with the polyurethane skeleton. [ka]

[0040] On the other hand, examples of terminals that do not bond to a structure containing a polyurethane skeleton include the following structures: -O- on the left side bonds to the structure shown in formula (1). [ka]

[0041] Furthermore, the terminal that is not bonded to the structure containing the polyurethane skeleton may have the following structure containing a hydroxyl group: In the following structure, R represents a hydrocarbon having 1 to 10 carbon atoms (preferably 1 to 5). The following structure shows the state when, for example, a silicone oil modified at both ends with carbinol is used for the polysiloxane segment, and one terminal is not bonded to the polyurethane skeleton. [ka] When a side-chain modified carbinol-modified silicone oil is used, the structure represented by formula (1) can be bonded to the polyurethane skeleton via the structure represented by formula (2).

[0042] The polysiloxane segment preferably has a structure in which polysiloxanes having a structure represented by the following formula (3) are urethane-bonded. [ka] (In formula (3), I and m are the average number of moles added, I is 7 to 195, m is 1 to 10, and n is an integer of 1 to 5. The siloxane structure represented by (-O-Si(CH3)2-) and (-O-Si(CH3)((CH2) n The arrangement of the structure represented by (OH)-) may be a block copolymer or a random copolymer.

[0043] When the polysiloxane segment has a structure in which polysiloxanes having the structure represented by the above formula (3) are urethane-bonded, the moisture absorption suppression effect is further enhanced. This is presumably because the siloxane is present in the vicinity of the urethane skeleton. In the above formula (3), I is preferably an integer of 40 to 160, m is preferably an integer of 2 to 10, and n is preferably an integer of 1 to 3.

[0044] The polysiloxane segment may be bonded to the polyurethane skeleton via a structure represented by the following formula (4). [ka] (In formula (4), * represents a polyurethane skeleton.) The -O- on the left side of the structure represented by formula (4) bonds to Si in the structure represented by formula (1). Si in the structure represented by formula (4) bonds to -O- in the siloxane structure. In other words, siloxane repeating structures may be bonded to both sides of the structure represented by formula (4).

[0045] <Method for measuring storage modulus> The storage modulus can be obtained by measuring the dynamic viscoelasticity of a sample under set conditions of frequency and temperature using a dynamic viscoelasticity device, and creating a master curve at a reference temperature from the measurement data.

[0046] A master curve is created based on the temperature-time conversion rule. The horizontal axis represents frequency and the vertical axis represents elastic modulus. The master curve can be created by shifting the frequency dispersion data measured at each temperature along the horizontal axis so that it overlaps with the data at the reference temperature. From the obtained master curve, for example, by curve fitting based on the generalized Maxwell model and formulating it, 1 × 10 ―3 The storage modulus of the elastic member in Hz can be calculated.

[0047] <Method for measuring crosslink density> The crosslink density of polyurethane can be indirectly determined by the spin-spin relaxation time in pulsed NMR. It can be measured quantitatively. When the crosslink density is low, the molecular mobility of the segments is large and it takes time to relax, so the spin-spin relaxation time (T2 L ) becomes larger.

[0048] The spin-spin relaxation time (T2) is measured by the solid echo method using a pulsed NMR instrument. The pulsed NMR apparatus is an apparatus for evaluating the mobility of polymer molecules such as rubber from the mobility (relaxation time) of hydrogen atoms in the molecular chain, and in this embodiment, the solid echo method is used as the sequence. The solid echo method using the pulsed NMR apparatus itself can be a known method and is not particularly limited.

[0049] By measuring the spin-spin relaxation time T2 (transverse relaxation time) by pulsed NMR, a T2 relaxation curve (free induction decay curve) can be obtained. In this embodiment, the T2 relaxation curve is separated into two components according to the length of the relaxation time. Specifically, the T2 relaxation curve is separated into two components by curve fitting to the following equation, and the component with the long relaxation time, T2 relaxation time (T2 L), and the T2 relaxation time of the component with a short relaxation time (T2 S ) is calculated. TIFF2025177758000014.tif17153M(t): Macroscopic magnetization A L : Intensity of the component with long relaxation time at t=0 T2 L : T2 relaxation time of components with long relaxation times A S : Intensity of the component with short relaxation time at t=0 T2 S : T2 relaxation time of the component with short relaxation time mi: Weibull modulus

[0050] <Method for measuring siloxane components> Siloxane components can be analyzed using the following method. For example, a method using trimethyl orthoformate as a methoxy derivatizing agent is known. Trimethyl orthoformate, methanol, sulfuric acid, and an elastic material are mixed and reacted at reflux temperature for several hours to decompose the siloxane segments into siloxane units. This can then be analyzed using GCMS or other methods to analyze and quantify the structure.

[0051] More specifically, the analysis can be carried out as follows. The structure represented by formula (1) can be quantified by the following method. A standard sample was prepared by mixing 524 mg of silicone oil (product name "KF-96A-100cs", manufactured by Shin-Etsu Chemical Co., Ltd.), 272 mg of sulfuric acid, 28.4 g of trimethyl orthoformate, and 8.75 g of methanol, and reacting the mixture at reflux temperature for 5 hours. The solution after the reaction was diluted with a solvent to create four levels of different concentrations. The four samples were analyzed by GCMS, and a calibration curve was created using the peak intensity and concentration of the Si-O component.

[0052] Next, a measurement sample is cut out from the center of the elastic member of the cleaning blade. 524 mg of sample is mixed with 272 mg of sulfuric acid, 28.4 g of trimethyl orthoformate, and 8.75 g of methanol, and the mixture is allowed to react at reflux temperature for 5 hours. After the reaction, the supernatant is sampled and analyzed by GCMS. The mass percentage of the structure represented by formula (1) in the polyurethane elastomer is calculated from the peak intensity of the Si-O component and the calibration curve.

[0053] Regarding the structure shown in formula (2), the sample after the above reaction is 1 Analysis by H-NMR When the structure shown in formula (2) is used, that is, when a side-chain modified silicone oil is used, the structure is one in which two methoxy groups and one methyl group are bonded to the Si at the end of the polyurethane elastomer. On the other hand, when a terminally modified silicone oil is used, the polyurethane elastomer has a structure in which one methoxy group and two methyl groups are bonded to the Si at its terminal. The structure can be inferred from the peak intensity ratio of the two bonds.

[0054] <About nurate bonds> Increasing the crosslink density in the polyurethane tends to increase the elastic modulus of the elastic member, narrowing the nip when it comes into contact with the member to be cleaned, which can be detrimental to contact stability. One way to increase the crosslink density without increasing the elastic modulus too much is to reduce the rigid components in the polyurethane elastomer.

[0055] As a rigid component, it is desirable to minimize nurate bonds and make them rich in urethane bonds. Specifically, in FT-IR measurements of elastic materials using diamond as an ATR crystal, -1 Peak intensity of 1538 cm -1 The ratio of the peak intensity to the peak intensity (1415cm -1 Peak intensity / 1538cm -1 The peak intensity value of the peak intensity (peak intensity value) is preferably 0.50 to 0.65.

[0056] 1415 cm in FT-IR analysis of elastic materials using diamond as an ATR crystal -1The peak at 1538 cm corresponds to the isocyanurate ring. -1 The peak at 1415 cm corresponds to the NH bending angle of the urethane bond. ―1 Peak intensity / 1538cm ―1 The peak intensity value being in the range of 0.50 to 0.65 indicates that there are few nurate bonds in the elastic member.

[0057] 1415cm -1 Peak intensity / 1538cm -1 When the peak intensity value (peak intensity ratio) is greater than 0.65, it indicates that a large number of nurate bonds are present in the elastic member. By setting the peak intensity ratio to 0.50 to 0.65, it is possible to obtain an elastic member that does not have an excessively large storage modulus and that has excellent contact stability with the member to be cleaned.

[0058] 1415cm -1 Peak intensity / 1538cm -1 In order to set the peak intensity value in the above-mentioned specific range, methods such as reducing the nurate bond and making the composition urethane-rich can be exemplified. Specifically, methods such as using a urethane-forming catalyst instead of a catalyst that promotes nurate formation, bringing the compounding ratio of -NCO to -OH in the prepolymer closer to 1, and setting the reaction temperature when reacting the prepolymer materials to 100°C or less can be exemplified.

[0059] <About Polymeric MDI> When the side of the cleaning blade that contacts the surface of the member to be cleaned is defined as the leading edge of the cleaning blade, the elastic member has a plate shape at least at the leading edge, with a main surface (4) facing the member to be cleaned and a leading edge surface (5) that forms a leading edge together with the main surface. It is assumed that a third line segment is drawn on the leading edge, parallel to the leading edge and 0.5 mm away from the leading edge. The length of the third line segment is L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the third line segment are designated P0', P1', and P2', respectively.

[0060] The samples sampled at P0', P1', and P2' are heated and vaporized in an ionization chamber, and then heated to 1000°C at a heating rate of 10°C / s using a direct sample introduction mass spectrometer that ionizes the sample molecules. The resulting detected amount of all ions is designated M1, and the integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value range of 380.5 to 381.5 derived from the polymeric MDI is designated M2. In this case, M2 It is preferred that / M1 is less than 0.0010.

[0061] It is preferable to use 4,4'-MDI as the isocyanate, which has high reactivity and in which two isocyanate groups have equal reactivity. On the other hand, as mentioned above, it is preferable to minimize the use of polymeric MDI, which is a trifunctional MDI, and it is particularly preferable not to use it at all. Specifically, it is preferable that M2 / M1 is less than 0.0010. When M2 / M1 satisfies the above specific range, it is easy to achieve a good range for the storage modulus.

[0062] M2 / M1 is more preferably 0.0009 or less. The smaller M2 / M1 is, the more preferable, and although there is no particular lower limit, it is preferably 0.0000 or more. When M2 / M1 is 0.0010 or more, the storage modulus tends to be large due to the rigidity of the polymeric MDI.

[0063] Furthermore, it is preferable to minimize the amount of crystalline structures in polyurethane. Specifically, it is preferable to minimize the amount of materials that easily form crystalline structures, such as 1,4-butanediol, and to enrich the polyurethane with crosslinkers, such as trimethylolpropane. Crosslinkers such as trimethylolpropane make it easier to increase the distance between urethane bonds, making it more difficult for crystalline structures to form.

[0064] <Viaduct density> The crosslink density can be increased, for example, by increasing the crosslinking agent concentration in the raw material composition of the elastic member. Taking into account the storage modulus, the crosslinking agent concentration in the raw material composition of the elastic member is preferably 0.30 to 0.70 mmol / g, more preferably 0.40 to 0.61 mmol / g, and even more preferably 0.50 to 0.60 mmol / g.

[0065] The method for calculating the crosslinker concentration is described below. For example, it can be quantified by pyrolysis GC / MS. Polyhydric alcohols are detected by pyrolysis GC / MS under the following measurement conditions: Device: Pyrolysis equipment: EGA / PY-3030D (product name, manufactured by Frontier Labs) Gas chromatography device: TRACE1310 gas chromatograph (product name, manufactured by Thermo Fisher Scientific) Mass spectrometer: ISQLT (product name, manufactured by Thermo Fisher Scientific) Pyrolysis temperature: 500℃ GC column: 0.25mm inner diameter x 30m stainless steel capillary column Stationary phase 5% phenylpolydimethylsiloxane Heating conditions: Hold at 50°C for 3 minutes, then heat to 300°C at 8°C / min MS conditions: Mass number range m / z10~650 Scan speed: 1 second / scan The type of polyhydric alcohol is identified using GC / MS. A calibration curve is created using GC analysis of known concentrations of the identified polyhydric alcohol species, and quantification is performed from the GC peak area ratio to calculate the crosslinker concentration in the raw material composition.

[0066] When the elastic member is left for 24 hours or more in an environment of 24°C and 50% relative humidity, the hardness is preferably 60.0 to 90.0, and more preferably 70.0 to 80.0. The hardness refers to the International Rubber Hardness Scale (IRHD), and indicates a value measured using a hardness tester according to the International Rubber Hardness Test M Method specified in JIS K 6253.

[0067] The hardness after leaving the elastic material in an environment of 24°C and 50% relative humidity for 24 hours or more is the initial hardness. Then, the sample is transferred to an environment with a temperature of 24°C and a relative humidity of 95%, and the hardness after being left for 24 hours or more is taken as the hardness after being left. The hardness reduction rate calculated by the following formula is preferably 0.20 to 0.90%, and more preferably 0.30 to 0.85%. Hardness reduction rate (%) = (initial hardness at 50% relative humidity - hardness after leaving at 95% relative humidity) / hardness at 50% relative humidity x 100 The initial hardness and hardness after standing refer to the International Rubber Hardness Scale (IRHD), and indicate values ​​measured using a hardness tester according to the International Rubber Hardness Test M Method specified in JIS K 6253.

[0068] <About the constituent materials> [Support member] The cleaning blade of the present disclosure has a support member that supports the elastic member. The material constituting the support member is not particularly limited, and examples thereof include metal materials such as steel plate, stainless steel plate, zinc-plated steel plate, and chrome-free steel plate, and resin materials such as 6-nylon and 6,6-nylon. The shape and structure of the support member are not particularly limited. For example, one end of the elastic member of the cleaning blade is supported by the support member, as shown in FIG.

[0069] [Elastic member] The elastic member contains a polyurethane elastomer having polysiloxane segments. The polyurethane elastomer constituting the elastic member is obtained from raw materials such as polyol, chain extender, crosslinking agent, polyisocyanate, catalyst, and other additives in addition to polysiloxane. Polyurethane elastomers are the reaction products of urethane prepolymers and silicone oils having functional groups that can react with isocyanate groups (or hydroxyl groups). Urethane prepolymers are the reaction products of polyols and polyisocyanates. The raw materials for the polyurethane elastomer will be described in detail below.

[0070] As the polysiloxane, various modified silicone oils having a reactive group among those having a dimethylsiloxane structure can be used. Carbinol-modified silicone oils are preferred. Examples include carbinol-modified silicone oils whose terminals are modified and carbinol-modified silicone oils whose side chains are modified. Among these, carbinol-modified silicone oils having primary hydroxyl groups at the terminals are more preferred, as they have high reactivity with isocyanates and are easily immobilized in polyurethane elastomers. For example, commercially available products such as "KF-6001 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.)," "Silmer OH J10 (trade name, manufactured by Siltec Corporation)," and "X-22-4039 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.)" can be used.

[0071] Examples of polyols include polyester polyols such as polyethylene adipate polyol, polybutylene adipate polyol, polyhexylene adipate polyol, (polyethylene / polypropylene) adipate polyol, (polyethylene / polybutylene) adipate polyol, and (polyethylene / polyneopentylene) adipate polyol; polycaprolactone polyols obtained by ring-opening polymerization of caprolactone; polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; polycarbonate diols, etc. These may be used alone or in combination of two or more.

[0072] Among the above polyols, polyester polyols using adipate are preferred because they can produce polyurethane elastomers with excellent mechanical properties. Polyester polyols using butylene adipate are more preferred. For example, commercially available products include "Nippolan 3027 (trade name, manufactured by Tosoh Corporation)" with a number average molecular weight of 2,500, and "Nippolan 3027 (trade name, manufactured by Tosoh Corporation)" with a number average molecular weight of 2,000. 00 "Nippolan 4010 (product name, manufactured by Tosoh Corporation)" can be used.

[0073] As the chain extender, glycols, trihydric or higher polyhydric alcohols, etc., which are capable of extending the polyurethane elastomer chain, can be used. Examples of glycols include ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG), dipropylene glycol (DPG), 1,4-butanediol (1,4-BD), 1,6-hexanediol (1,6-HD), 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, xylylene glycol (terephthalyl alcohol), and triethylene glycol.

[0074] Examples of trihydric or higher polyhydric alcohols include trimethylolpropane, glycerin, pentaerythritol, and sorbitol. These may be used alone or in combination of two or more. It is preferable to use these trihydric or higher polyhydric alcohols as crosslinking agents. Among the above polyhydric alcohols, trimethylolpropane is more preferable.

[0075] Examples of polyisocyanates include 4,4'-diphenylmethane diisocyanate (4,4'-MDI), polymeric MDI (pMDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), xylene diisocyanate (XDI), 1,5-naphthylene diisocyanate (1,5-NDI), p-phenylene diisocyanate (PPDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), tetramethylxylene diisocyanate (TMXDI), and carbodiimide-modified MDI. Among the above polyisocyanates, 4,4'-MDI is preferred because it has high reactivity and the two isocyanate groups have equivalent reactivities.

[0076] The catalyst may be a commonly used catalyst for curing polyurethane elastomers. Examples include tertiary amine catalysts, specifically the following: aminoalcohols such as dimethylethanolamine, N,N,N'-trimethylaminopropylethanolamine, and N,N'-dimethylhexanolamine; trialkylamines such as triethylamine; tetraalkyldiamines such as N,N,N'N'-tetramethyl-1,3-butanediamine; triethylenediamine, piperazine compounds, and triazine compounds. Organic acid salts of metals such as potassium acetate and potassium alkali octylate may also be used. Furthermore, metal catalysts typically used in urethanization, such as dibutyltin dilaurate, may also be used. These may be used alone or in combination.

[0077] The catalyst is preferably N,N'-dimethylhexanolamine. Commercially available catalysts include Kao Raiser No. 25 (trade name, manufactured by Kao Corporation). An ethylene glycol solution of potassium acetate is also preferred. Commercially available catalysts include POLYCAT 46 (trade name, manufactured by Air Products Japan).

[0078] For example, the polyurethane elastomer preferably contains, as constituent components, at least one polyol selected from the group consisting of polyester polyols and polyether polyols, a trihydric or higher polyhydric alcohol, and 4,4'-MDI. The raw materials constituting the elastic member may contain additives such as pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers, and light stabilizers, as required.

[0079] <Cleaning Blade Manufacturing Method> The method for producing the cleaning blade according to the present disclosure is not particularly limited, and an appropriate method may be selected from known methods.

[0080] The method for producing an elastic member containing a polyurethane elastomer is not particularly limited, but preferably includes, for example, the following steps. The polyurethane elastomer composition is preferably produced by a prepolymer method using a prepolymer having as uniform a molecular weight distribution as possible. The method preferably includes a step of first reacting a polyol with a polyisocyanate to obtain a prepolymer. The NCO content in the prepolymer is not particularly limited, but is preferably 3.00 to 15.00 mass%, and more preferably 6.00 to 10.00 mass%.

[0081] Subsequently, a mixture of polysiloxane, a crosslinking agent, and a catalyst (curing agent) is added to the obtained prepolymer and mixed to obtain a polyurethane elastomer composition. The curing agent may also contain a polyol.

[0082] After placing the support member in a mold for forming a cleaning blade, the polyurethane elastomer composition is injected into the cavity and heated to cure, thereby obtaining a cleaning blade in which the plate-like blade member and the support member are integrated. A known mold release agent may be applied to the mold. Alternatively, a polyurethane elastomer sheet may be separately molded from the polyurethane raw material composition, and then cut into strips to prepare elastic members. The adhesive portion of the elastic member may then be superimposed on a support member to which an adhesive has been applied or attached, and the resulting material may be bonded by heating and pressurizing.

[0083] The polyurethane elastomer composition can also be used as a material for a urethane molded article. For example, the polyurethane elastomer composition can be injected into a sheet mold, cured, and then demolded to form a urethane molded article.

[0084] <Process cartridge and electrophotographic image forming apparatus> The cleaning blade can be incorporated into a process cartridge that is detachably attached to an electrophotographic image forming apparatus. Specifically, for example, the cleaning blade according to this embodiment can be used as the cleaning blade in a process cartridge that includes an image carrier as a member to be cleaned and a cleaning blade that is arranged to be able to clean the surface of the image carrier. The process cartridge contributes to the stable formation of high-quality electrophotographs.

[0085] An electrophotographic image forming apparatus according to one aspect of the present invention includes an image carrier such as a photoreceptor, and a cleaning blade arranged to be able to clean the surface of the image carrier, the cleaning blade being the cleaning blade according to this aspect. The electrophotographic image forming apparatus is capable of stably forming high-quality electrophotographic images. [Example]

[0086] The present invention will be described below with reference to Production Examples, Examples, and Comparative Examples, but the present disclosure is not limited to these Examples. Raw materials other than those indicated in the Examples and Comparative Examples were reagents or industrial chemicals.

[0087] In the following Examples 1 to 14 and Comparative Examples 1 to 5, the integrally molded cleaning blades shown in Fig. 1 were produced and evaluated. The formulation of the polyurethane elastomer composition for each Example and Comparative Example, the physical properties of the obtained elastic members, and the evaluation results are shown in Tables 1 and 2.

[0088] Example 1 [Support member] A 1.6 mm thick galvanized steel plate was prepared and processed to obtain a support member having an L-shaped cross section, as shown by reference numeral 3 in FIG. A single layer urethane-metal adhesive (trade name: Chemlok 219, manufactured by Lord Corporation) was applied to the portion of the support member that would come into contact with the elastic member.

[0089] [Preparation of raw material for elastic member] (prepolymer) 327.0 g of 4,4'-diphenylmethane diisocyanate (trade name: Millionate MT, manufactured by Tosoh Corporation) (hereinafter referred to as 4,4'-MDI) as an isocyanate 673.0 g of butylene adipate polyester polyol (trade name: Nipporan 3027, manufactured by Tosoh Corporation) (hereinafter referred to as PBA2500) having a number average molecular weight of 2500 as polyol The above materials were reacted at 80° C. for 3 hours to obtain a prepolymer with an NCO content of 8.80% by weight.

[0090] (hardening agent) 84.3g of trimethylolpropane (manufactured by Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as TMP) 0.25 g of N,N'-dimethylhexanolamine (trade name: Kao Raiser No. 25, manufactured by Kao Corporation) (hereinafter referred to as No. 25) 8.7g of carbinol-modified silicone oil (product name: KF-6001, manufactured by Shin-Etsu Chemical Co., Ltd.) (hereafter referred to as KF-6001) The above materials were mixed to make a curing agent.

[0091] A curing agent was mixed with the resulting prepolymer to obtain a polyurethane elastomer composition. The adhesive-coated portion of the support member was positioned so that it protruded into the cavity of the mold for forming a cleaning blade. A polyurethane elastomer composition was poured into the mold for forming a cleaning blade, cured at 130°C for 5 minutes, and then demolded to obtain an integrally molded product of polyurethane and the support member.

[0092] Before injecting the polyurethane elastomer composition into the mold, the mold was coated with release agent A. Release agent A was prepared by mixing 5.06 g of ELEMENT14 PDMS 1000-JC (trade name, manufactured by Momentive Performance Materials), 6.19 g of ELEMENT14 PDMS 10K-JC (trade name, manufactured by Momentive Performance Materials), 3.75 g of SR1000 (trade name, manufactured by Momentive Performance Materials), and 85 g of EXXSOL DSP145 / 160.

[0093] The tip end of this integrally molded polyurethane elastomer was appropriately cut to obtain a plate-shaped elastic member having a main surface and a tip surface that, together with the main surface, constitutes a tip edge. The tip edge angle was 90 degrees, and the lengths of the elastic member in the short, thickness, and length directions were 7.5 mm, 1.8 mm, and 240 mm, respectively. The resulting cleaning blade was evaluated by the following method.

[0094] [Method for calculating storage modulus] The storage modulus of the elastic member was measured by temperature frequency dispersion using a dynamic viscoelasticity device, and calculated by creating a master curve at a reference temperature of 24°C based on the temperature-time conversion rule.

[0095] The conditions for measuring the dynamic viscoelasticity are as follows: Apparatus: Dynamic viscoelasticity measuring apparatus (trade name: DMA EXPLEXOR 500N, manufactured by NETZSCH) Measurement mode: tension Static strain: 2% Dynamic strain: 0.5% Measurement temperature: -30℃ to 80℃ (2℃ increments, 56 points) Measurement frequency: 0.1~100Hz (5 points)

[0096] From the dynamic viscoelasticity measurement results obtained, a master curve at a reference temperature of 24°C was created using the software in the device. From the obtained master curve, a mathematical approximation was performed based on the generalized Maxwell model. The generalized Maxwell model is as follows:

number

[0097] If we separate the above generalized Maxwell model into the storage modulus E' and loss modulus E'', we get the following:

number

[0098] In the mathematical approximation, the number of terms in the generalized Maxwell model is the elastic term (Ee)1 + the viscoelastic term (Ei)20 (i = 1 to 20). τi is 10 ―8 ~10 5 They scored 20 points between them. Ee and Ei were optimized using the GRG nonlinear (generalized reduced gradient method) so that the difference between E' and E'' of the generalized Maxwell model and E' and E'' of the master curve was minimized. Specifically, the solver function of Excel was used. From the obtained master curve approximation, E'(1)(1×10 ―3 Calculate E' in Hz and check if the vibration frequency of the elastic member is 1×10 -3 The storage modulus was calculated as Hz.

[0099] The measurement samples were prepared as follows. The sample was prepared so as to include the corner (for example, the leading edge) of the elastic member at the contact point with the member to be cleaned, and was cut into a strip measuring 50 mm in length, 2 mm in width, and 1.8 mm in thickness.

[0100] [Measurement of T2 relaxation time] The spin-spin relaxation time (T2) was measured by the solid echo method in pulsed NMR analysis. The sample was a piece cut from the elastic member of the cleaning blade at the measurement position described below, or a urethane molded article described below. The above sample was cut into small pieces of 1 mm x 1 mm, and 1 g of each was prepared in a test tube.

[0101] The measurement conditions for pulsed NMR are as follows: Equipment: JNM-MU25 (manufactured by JEOL) Condition: Solid echo method Measurement environment: 50°C Number of measurements: 128 The measurement results were separated into two components using the least squares method in the instrument software, and the spin-spin relaxation times (T2 L and T2 S ) was obtained.

[0102] In the present disclosure, the obtained T2 relaxation curve is separated into two components according to the length of the relaxation time. Specifically, the T2 relaxation curve is separated into two components by curve fitting to the following equation, and the spin-spin relaxation time (T2 L ), the spin-spin relaxation time of the short-relaxation component (T2 S ) was calculated.

number

[0103] [FT-IR analysis of elastic materials using the ATR method] Elastic material 1415cm -1 and the peak intensity at 1538cm -1 The peak intensity values ​​were measured by the ATR method using FT-IR. The sample was cut out from the elastic member of the cleaning blade at a measurement position described later.

[0104] The FT-IR measurement conditions are as follows: Equipment: FT / IR-4700 (JASCO) Measurement mode: ATR method (crystal: diamond) Accumulation count: 64 times Measurement position: The length of the tip edge of the cleaning blade is defined as L, and measurements were taken at positions 1 / 8L, 1 / 2L, and 7 / 8L from one end on the edge. From the obtained peak intensity, 1415 cm -1 Peak intensity / 1538cm -1 The peak intensity values ​​were calculated, and the arithmetic mean values ​​are shown in Table 1.

[0105] [Method for measuring M1 and M2] Measurement of M1 and M2 was carried out by the direct sample introduction method (DI method), in which the sample was directly introduced into the ion source without passing through a gas chromatograph (GC). The equipment used was the POLARIS Q manufactured by Thermo Fisher Scientific Co., Ltd. Direct Exposure Probe (DEP) was used. Assuming that a line segment was drawn on the distal end surface of the elastic member parallel to the distal edge at a distance of 0.5 mm from the distal edge, the length of the line segment was defined as L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the line segment were defined as P0', P1', and P2', respectively. Polyurethane was scraped off from points P0', P1', and P2' using a biocutter.

[0106] 0.1 μg of sample to be sampled at each of P0′, P1′, and P2′ was fixed to a filament at the tip of the probe and directly inserted into the ionization chamber, which was then rapidly heated from room temperature to 1000°C at a constant temperature increase rate (10°C / s), and the vaporized gas was detected by a mass spectrometer. The detected amount M1 of all ions was calculated by adding up the integrated intensities of all peaks in the obtained total ion current thermogram. The integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value range of 380.5 to 381.5, which is derived from polymeric MDI, was defined as M2, and M2 / M1 was calculated. The arithmetic mean value of the values ​​obtained for P0', P1', and P2' was defined as the value of M2 / M1 in the present disclosure.

[0107] <Evaluation of moisture absorption rate> A piece measuring 7.5 mm wide x 30 mm long and 1.8 mm thick was cut out from the center of the elastic member of the cleaning blade, and left in an environment of 24°C and 50% relative humidity for 24 hours or more, after which the initial weight was measured. The 30 mm length of the piece was part of the cleaning blade in the longitudinal direction. Next, the sample was transferred to an environment of 24°C and 95% relative humidity and left for 24 hours or more, after which the weight was measured and the moisture absorption rate was calculated using the following formula. Moisture absorption rate (%) = (weight after standing at 95% relative humidity - initial weight at 50% relative humidity) / initial weight at 50% relative humidity × 100

[0108] <Evaluation of hardness reduction rate> A piece measuring 7.5 mm wide x 10 mm long and 1.8 mm thick is cut from the center of the elastic member of the cleaning blade, and left at a temperature of 24°C and a relative humidity of 50% for at least 24 hours. The initial hardness (IRHD) is then measured under the following conditions: The 30 mm length of the piece corresponds to part of the cleaning blade in the longitudinal direction. Equipment: Wallace hardness tester (manufactured by Wallace) Conditions: International rubber hardness test M method specified in JIS K 6253 Hardness: International Rubber Hardness (IRHD) Next, the sample was transferred to an environment of 24°C and 95% relative humidity and left for 24 hours or more, and then the hardness after leaving was measured under the same conditions as above, and the hardness reduction rate was calculated using the following formula. Hardness reduction rate (%) = (initial hardness at 50% relative humidity - hardness after leaving at 95% relative humidity) / hardness at 50% relative humidity x 100

[0109] <Cleaning performance evaluation> The motor of a color laser beam printer (product name: HP Color LaserJet Enterprise 5700dn, manufactured by HP) was modified to double its drive speed. The cleaning blade obtained by the above-described method was incorporated into the cyan cartridge of the printer as a cleaning blade for the photoreceptor, which is the member to be cleaned. Furthermore, the toner in the developing machine of the cyan cartridge was completely replaced with Toner 1, which will be described later.

[0110] Next, the printer was left in a high humidity environment (temperature 24°C, relative humidity 95%) for 24 hours, and then moved to an environment of temperature 24°C, relative humidity 80%, and 10,000 images were formed. After forming 10,000 images, halftone images were output as evaluation images, and the cleaning blade-induced The image was evaluated by visually checking whether or not image defects (streaks on the image) occurred. ◯: No image defects occurred. ×: Image defects occurred.

[0111] <Method of manufacturing toner 1> The toner for evaluation was Toner 1 produced by the following method: In the following, unless otherwise specified, all parts are by weight.

[0112] (Preparation step of aqueous medium 1) A reaction vessel equipped with a stirrer, thermometer, and reflux condenser was charged with 650.0 parts of ion-exchanged water, 14.0 parts of sodium phosphate (12-hydrate, manufactured by Rasa Kogyo Co., Ltd.), and the mixture was kept at 65°C for 1.0 hour while purging with nitrogen. A calcium chloride aqueous solution prepared by dissolving 9.2 parts of calcium chloride (dihydrate) in 10.0 parts of ion-exchanged water was added all at once while stirring at 15,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare an aqueous medium containing a dispersion stabilizer. Furthermore, 10% by mass of hydrochloric acid was added to the aqueous medium to adjust the pH to 5.0, yielding aqueous medium 1.

[0113] (Preparation step of polymerizable monomer composition) Styrene: 60.0 parts CI Pigment Blue 15:3:6.5 parts The materials were placed in an attritor (manufactured by Mitsui Miike Chemical Engineering Co., Ltd.), and further dispersed using zirconia particles with a diameter of 1.7 mm at 220 rpm for 5.0 hours to prepare a pigment dispersion. The following materials were added to the pigment dispersion. Styrene: 20.0 parts n-Butyl acrylate: 20.0 parts Crosslinking agent (divinylbenzene): 0.3 parts Saturated polyester resin: 5.0 parts (Polycondensation polymer of propylene oxide-modified bisphenol A (2-mol adduct) and terephthalic acid (molar ratio 10:12), glass transition temperature Tg = 68°C, weight average molecular weight Mw = 10,000, molecular weight distribution Mw / Mn = 5.12) Fischer-Tropsch wax (melting point 78°C): 7.0 parts The mixture was kept at 65°C and uniformly dissolved and dispersed at 500 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare a polymerizable monomer composition.

[0114] (granulation process) While maintaining the temperature of the aqueous medium 1 at 70°C and the rotation speed of the TK homomixer at 15,000 rpm, the polymerizable monomer composition was charged into the aqueous medium 1, and 10.0 parts of t-butyl peroxypivalate as a polymerization initiator was added. Granulation was continued for 10 minutes while maintaining the stirring speed at 15,000 rpm with the stirring device.

[0115] (Polymerization and distillation processes) After the granulation step, the agitator was replaced with a propeller agitator blade, and polymerization was carried out for 5.0 hours while stirring at 150 rpm and maintaining the temperature at 70°C, and then the temperature was raised to 85°C and heated for 2.0 hours to carry out the polymerization reaction. Thereafter, the reflux piping of the reaction vessel was replaced with a cooling pipe, and the slurry was heated to 100° C. to carry out distillation for 6 hours to remove unreacted polymerizable monomers, thereby obtaining a toner base particle dispersion liquid.

[0116] (Polymerization of organosilicon compounds) 60.0 parts of ion-exchanged water was weighed into a reaction vessel equipped with a stirrer and a thermometer, and the pH was adjusted to 4.0 using 10% by mass of hydrochloric acid. This was heated with stirring until the temperature reached 40°C. . Then, 40.0 parts of methyltriethoxysilane, an organosilicon compound, was added and stirred for 2 hours or more to carry out hydrolysis. The end point of the hydrolysis was confirmed by visual inspection when the oil and water were no longer separated and a single layer was formed, and the mixture was cooled to obtain a hydrolyzed solution of the organosilicon compound. The resulting toner base particle dispersion was cooled to 55°C, and 25.0 parts of the organosilicon compound hydrolyzate was added to initiate polymerization of the organosilicon compound. After 15 minutes of incubation, the pH was adjusted to 5.5 with a 3.0% by weight aqueous solution of sodium bicarbonate. After 60 minutes of incubation at 55°C with continued stirring, the pH was adjusted to 9.5 with a 3.0% by weight aqueous solution of sodium bicarbonate, and the mixture was further incubated for 240 minutes to obtain a toner particle dispersion.

[0117] (Washing and drying process) After the polymerization process was completed, the toner particle dispersion was cooled, and hydrochloric acid was added to the toner particle dispersion to adjust the pH to 1.5 or less, and the dispersion was left to stand with stirring for 1 hour, after which solid-liquid separation was carried out using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to make a dispersion again, and then solid-liquid separation was carried out using the above-mentioned filter to obtain a toner cake. The obtained toner cake was dried and classified in a thermostatic chamber at 40° C. for 72 hours, and toner 1 was obtained.

[0118] <Examples 2 to 14 and Comparative Examples 1 to 5> A prepolymer, a curing agent, and a polysiloxane were prepared and mixed to obtain a polyurethane elastomer composition in the same manner as in Example 1, except that the ingredients and amounts were changed as shown in Tables 1 and 2. A cleaning blade was produced using the obtained polyurethane elastomer composition, and the obtained cleaning blade was evaluated in the same manner as in Example 1. The evaluation results are shown in Tables 1 and 2.

[0119] Details of the materials used other than those shown in Example 1 are shown below. Polybutylene adipate polyester polyol having a number average molecular weight of 2000 (trade name: Nipporan 4010, manufactured by Tosoh Corporation) (hereinafter referred to as PBA2000) Polyhexylene adipate polyester polyol having a number average molecular weight of 1,000 (trade name: Nipporan 164, manufactured by Tosoh Corporation) (hereinafter referred to as PHA1000) Polymeric MDI (trade name: Millionate MR-400, manufactured by Tosoh Corporation) (hereinafter referred to as pMDI) 1,4-Butanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as 1,4-BD) POLYCAT46 (manufactured by Air Products Japan) (hereinafter referred to as PC46) Silmer OH J10 (manufactured by Siltec Corporation) X-22-4039 (Shin-Etsu Chemical Co., Ltd.) KF-96A-100cs (Shin-Etsu Chemical Co., Ltd.)

[0120] Comparative Example 1 did not contain a siloxane component, so the moisture absorption suppression effect was small, resulting in poor image quality. Comparative Example 2 contained a siloxane component, but it was not fixed in the polyurethane elastomer, so the moisture absorption suppression effect was small, resulting in poor image quality. Comparative Example 3 contained a siloxane segment, but T2 L In Comparative Example 4, the storage modulus was small, so the contact force was small and image defects occurred. In Comparative Example 5, the storage modulus was large, so nip formation was unstable and image defects occurred.

[0121] Example 15 A polyurethane elastomer composition having the same composition as in Example 9 was poured into a 2 mm thick sheet mold, cured at 130°C for 5 minutes, and then demolded to obtain a 2 mm thick urethane molded article. The sheet mold used had been coated with the above-mentioned mold release agent A before the polyurethane elastomer composition was poured into it.

[0122] The moisture absorption rate and hardness reduction rate of the obtained urethane molded article were measured in the same manner as in Example 1. The evaluation results are shown in Table 3. [Table 1]

[0123] In the table, the content of the structure represented by formula (1) indicates the content (mass %) of the structure represented by formula (1) in the polyurethane elastomer. Furthermore, a value of m of 0 in formula (2) indicates that the polyurethane elastomer does not have the structure represented by formula (2). Hardness (IRHD) indicates the hardness (initial hardness) after the elastic member is left in an environment of 24°C and 50% relative humidity for 24 hours. [Table 2] [Table 3]

[0124] The present disclosure relates to the following configurations. (Configuration 1) The device includes an elastic member containing polyurethane and a support member that supports the elastic member, An electrophotographic cleaning blade that cleans the surface of a moving member to be cleaned by bringing a part of the elastic member into contact with the surface of the member to be cleaned, In a 24°C environment, the vibration frequency of the elastic member is 1×10 -3 The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurements of the sample sampled from the elastic member in a 50°C environment, the spin-spin relaxation time (T2 L ) has a segment of 250-360 μs, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, the number I of structures represented by formula (1) per polysiloxane segment is 7 to 195; Electrophotographic cleaning blade. TIFF2025177758000021.tif40153 (configuration 2) The polysiloxane segment is bonded to the polyurethane skeleton via a structure represented by the following formula (2): 2. The electrophotographic cleaning blade according to claim 1, wherein the number m of structures represented by formula (2) per polysiloxane segment is 1 to 10. TIFF2025177758000022.tif44153 (In formula (2), n represents an integer of 1 to 5, and * represents a bonding site with the polyurethane skeleton.) (Configuration 3) In pulse NMR measurement of the sample sampled from the elastic member in a 50°C environment, the spin-spin relaxation time (T L 3. The electrophotographic cleaning blade according to claim 1, wherein the length of the cleaning blade is 250 to 320 μs. (Configuration 4) 4. The cleaning blade for electrophotography according to Configuration 2 or 3, wherein m is an integer of 2 to 10. (Configuration 5) 5. The cleaning blade for electrophotography according to any one of Configurations 1 to 4, wherein the polyurethane elastomer contains 0.5 to 15% by mass of the structure represented by formula (1). (Configuration 6) 6. The cleaning blade for electrophotography according to any one of Configurations 1 to 5, wherein the polysiloxane segment has a structure in which polysiloxanes having a structure represented by the following formula (3) are urethane-bonded: TIFF2025177758000023.tif43153 (In formula (3), I and m are the average number of moles added, I is 7 to 195, m is 1 to 10, and n is an integer of 1 to 5. The siloxane structure represented by (-O-Si(CH3)2-) and (-O-Si(CH3)((CH2) n The arrangement of the structure represented by (OH)-) may be a block copolymer or a random copolymer. (Configuration 7) In the FT-IR measurement of the elastic member using diamond as the ATR crystal, 1415cm -1 Peak intensity of 1538 cm -1 7. The cleaning blade for electrophotography according to any one of configurations 1 to 6, wherein the ratio of the peak intensity to the peak intensity is 0.50 to 0.65. (Configuration 8) When the side of the electrophotographic cleaning blade that comes into contact with the surface of the member to be cleaned is defined as the tip side of the electrophotographic cleaning blade, the elastic member has a plate shape at least at the tip end side, the plate shape having a main surface facing the member to be cleaned and a tip end surface forming a tip end edge together with the main surface, When it is assumed that a third line segment is drawn on the tip surface parallel to the tip edge at a distance of 0.5 mm from the tip edge, The length of the third line segment is L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the third line segment are P0', P1', and P2', respectively; The samples sampled at P0', P1', and P2' are heated and vaporized in an ionization chamber, and a direct sample introduction mass spectrometer that ionizes sample molecules is used. The amount of all ions detected when the sample is heated to 1000°C at a heating rate of 10°C / s is defined as M1. When the integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value range of 380.5 to 381.5 derived from polymeric MDI is defined as M2, M2 / M1 is less than 0.0010, 8. The cleaning blade for electrophotography according to any one of Configurations 1 to 7. (Configuration 9) A process cartridge comprising the electrophotographic cleaning blade according to any one of Configurations 1 to 8 and a member to be cleaned. (Configuration 10) An electrophotographic image forming apparatus having the electrophotographic cleaning blade according to any one of Configurations 1 to 8 and a member to be cleaned. (Configuration 11) A urethane molded article containing polyurethane, In a 24°C environment, the vibration frequency of the polyurethane is 1×10-3 The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurements of a sample taken from the urethane molded body at 50°C, the spin-spin relaxation time (T2 L ) has a segment of 250-360 μs, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, A urethane molded article, wherein the number I of structures represented by formula (1) per one polysiloxane segment is 7 to 195. TIFF2025177758000024.tif40153(Configuration 12) The polysiloxane segment is bonded to the polyurethane skeleton via a structure represented by the following formula (2): 12. The urethane molded article according to claim 11, wherein the number m of the structures represented by formula (2) per one polysiloxane segment is 1 to 10. TIFF2025177758000025.tif44153 (In formula (2), n represents an integer of 1 to 5, and * represents a bonding site with the polyurethane skeleton.) [Explanation of symbols]

[0125] 1 cleaning blade, 2 elastic member, 3 support member, 4 main surface facing the member to be cleaned, 5 tip surface forming a tip edge together with the main surface, 6 member to be cleaned, 7 rotation direction of the member to be cleaned

Claims

1. The device includes an elastic member containing polyurethane and a support member that supports the elastic member, An electrophotographic cleaning blade that cleans the surface of a moving member to be cleaned by bringing a part of the elastic member into contact with the surface of the member to be cleaned, In a 24°C environment, the vibration frequency of the elastic member is 1×10 －３ The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurement of a sample sampled from the elastic member in a 50°C environment, the spin-spin relaxation time (T2 Ｌ ) has a segment of 250-360 μs, The polyurethane contains a polyurethane elastomer, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, the number I of the structure represented by formula (1) per polysiloxane segment is 7 to 195; Electrophotographic cleaning blade.

2. The polysiloxane segment is bonded to the polyurethane skeleton via a structure represented by the following formula (2):

2. The electrophotographic cleaning blade according to claim 1, wherein the number m of structures represented by formula (2) per one polysiloxane segment is 1 to 10. (In formula (2), n represents an integer of 1 to 5, and * represents a bonding site with the polyurethane skeleton.)

3. In pulse NMR measurement of the sample sampled from the elastic member in a 50°C environment, the spin-spin relaxation time (T2 Ｌ 2. The electrophotographic cleaning blade according to claim 1, wherein there is a segment in which the length of the edge of the cleaning blade is 250 to 320 μs.

4. 3. The cleaning blade for electrophotography according to claim 2, wherein m is an integer of 2 to 10.

5. 2. The cleaning blade for electrophotography according to claim 1, wherein the polyurethane elastomer contains the structure represented by formula (1) in an amount of 0.5 to 15% by mass.

6. 2. The cleaning blade for electrophotography according to claim 1, wherein the polysiloxane segment has a structure in which polysiloxanes having a structure represented by the following formula (3) are urethane-bonded: (In formula (3), I and m are the average number of moles added, I is 7 to 195, m is 1 to 10, and n is an integer of 1 to 5. (—O—Si(CH ３ ) ２ -) and a siloxane structure represented by (—O—Si(CH ３ ) ((CH ２ ) ｎ The arrangement of the structure represented by (OH)-) may be a block copolymer or a random copolymer.

7. In the FT-IR measurement of the elastic member using diamond as an ATR crystal, 1415 cm －１ The peak intensity of 1538 cm －１ 2. The cleaning blade for electrophotography according to claim 1, wherein the ratio of the peak intensity of the peak intensity to the peak intensity of the peak intensity is 0.50 to 0.

65.

8. When the side of the electrophotographic cleaning blade that comes into contact with the surface of the member to be cleaned is defined as the tip side of the electrophotographic cleaning blade, the elastic member has a plate shape at least at the tip end side, the plate shape having a main surface facing the member to be cleaned and a tip end surface forming a tip end edge together with the main surface, When it is assumed that a third line segment is drawn on the tip surface parallel to the tip edge at a distance of 0.5 mm from the tip edge, The length of the third line segment is defined as L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end side on the third line segment are defined as P0', P1', and P2', respectively; The sample sampled at each of P0', P1', and P2' is heated and vaporized in an ionization chamber, and a direct sample introduction type mass spectrometer that ionizes sample molecules is used. The amount of all ions detected when the sample is heated to 1000°C at a heating rate of 10°C / s is defined as M1. When the integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value in the range of 380.5 to 381.5 derived from the polymeric MDI is defined as M2, M2 / M1 is less than 0.0010; 2. The electrophotographic cleaning blade according to claim 1.

9. A process cartridge comprising the electrophotographic cleaning blade according to any one of claims 1 to 8 and a member to be cleaned.

10. An electrophotographic image forming apparatus, comprising the electrophotographic cleaning blade according to any one of claims 1 to 8 and a member to be cleaned.

11. A urethane molded article containing polyurethane, In a 24°C environment, the polyurethane has a vibration frequency of 1 x 10 －３ The storage modulus at Hz is 12.0 to 18.0 MPa, In pulse NMR measurement of a sample sampled from the urethane molded body in a 50°C environment, the spin-spin relaxation time (T2 Ｌ ) has a segment of 250-360 μs, The polyurethane contains a polyurethane elastomer, The polyurethane elastomer has a polysiloxane segment having a structure represented by the following formula (1): the polysiloxane segment is bonded to a structure containing a polyurethane skeleton in the polyurethane elastomer, A urethane molded article, wherein the number I of structures represented by formula (1) per one polysiloxane segment is 7 to 195.

12. The polysiloxane segment is bonded to the polyurethane skeleton via a structure represented by the following formula (2):

12. The urethane molded article according to claim 11, wherein the number m of structures represented by formula (2) per one polysiloxane segment is 1 to 10. (In formula (2), n represents an integer of 1 to 5, and * represents a bonding site with the polyurethane skeleton.)

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