Electrophotographic cleaning blade, process cartridge and electrophotographic image generation device

Abstract

An electrophotographic cleaning blade comprises an elastic component and a support component that supports the elastic component, wherein the elastic component has a first surface and a second surface at a free end section of the elastic component, which together with the first surface forms an edge; when the dynamic hardness is measured at predetermined measurement positions, the coefficient of variation of a maximum value DHmax from the dynamic hardnesses at measurement positions in the longitudinal direction of the elastic component is not greater than 0.20, the elastic component has a region in which the dynamic hardness decreases from the edge towards the inside of the elastic component; and in the region in which the dynamic hardness decreases, the coefficient of variation of the distance L between the predetermined measurement positions and the edge in the longitudinal direction of the elastic component is not greater than 0.28.

Description

TECHNICAL AREA

[0001] The present disclosure relates to an electrophotographic cleaning blade used in an electrophotographic image-generating device, a process cartridge and an electrophotographic image-generating device. STATE OF THE ART

[0002] An electrophotographic image-generating device (hereinafter referred to as an "electrophotographic device") is known to date, which includes various cleaning components to remove toner that remains on an image carrier component, for example a light-sensitive component, after a toner image has been transferred from the image carrier component to a transmission target component, for example paper or an intermediate transmission medium.

[0003] The cleaning component is known as an electrophotographic cleaning blade (hereinafter referred to simply as a cleaning blade) which uses a plate-shaped elastic component, the elastic component being frequently made (formed) from a polyurethane elastomer.

[0004] Furthermore, in recent years, with the improved image quality of electrophotographic equipment, toner particles have become smaller in diameter and more spherical, and the toner remaining on the image carrier component is more likely to slip through the cleaning blade. Consequently, a higher cleaning performance is required for the cleaning blade.

[0005] A method known for improving cleaning performance involves increasing the hardness of a contact section of a cleaning blade made of a polyurethane elastomer and reducing the contact gap width, thereby increasing the contact force of the cleaning blade with the image carrier component.

[0006] PTL 1 proposes a method for manufacturing a blade for an electrophotographic device, wherein the method comprises impregnating a contact area in contact with a counter component with a blocked isocyanate, releasing a blocking agent from the blocked isocyanate, and reacting the free isocyanate with urethane rubber to form a hardened layer with a low variation in surface hardness, wherein the isocyanate comprises an aromatic isocyanate.

[0007] Furthermore, PTL 2 discloses a blade for an electrophotographic device that is used in contact with a contact target component, wherein in the blade for the electrophotographic device at least one contact area of ​​the blade is formed in a silicone layer in which the silicone content decreases from the surface layer (area layer) of the contact area towards the inside, and the surface layer (area layer) of the silicone layer is formed in a hardened layer.

[0008] Furthermore, PTL 3 discloses a cleaning blade in which a contact area that is in contact with a counter-component is impregnated with a curable composition comprising a (meth)acrylate compound, and the amount of the curable composition decreases from the surface to the inside. CITATION LIST PATENT DOCUMENTS [PTL 1] Japanese Patent Application Disclosure Notice No. 2019-132982 [PTL 2] Japanese Patent Application Disclosure Notice No. 2004-233818 [PTL 3] Japanese Patent Application Disclosure Notice No. 2016-142860 SUMMARY OF THE INVENTIONAL PROBLEM

[0009] At least one aspect of the present disclosure is to provide a cleaning blade that minimizes the temporary slippage of toner remaining on a cleaning target component, caused by a change in the contact orientation of the cleaning blade relative to the cleaning target component when the electrophotographic image generation operation begins or stops, and which contributes to the stable generation of high-quality electrophotographic images. Furthermore, at least one aspect of the present disclosure is to provide a process cartridge that contributes to the stable generation of high-quality electrophotographic images. Additionally, at least one aspect of the present disclosure is to provide an electrophotographic image generation device. SOLUTION TO THE PROBLEM

[0010] According to at least one aspect of the present disclosure, an electrophotographic cleaning blade can be provided comprising an elastic component and a support component that supports the elastic component, wherein the elastic component has, at a free end section of the elastic component, a first surface and a second surface which together with the first surface forms an edge, in a cross-section perpendicular to a longitudinal direction of the elastic component and on a straight line bisecting an angle of the edge, when the dynamic hardness is measured at measurement positions at intervals of 10 µm from the edge, a coefficient of variation of a maximum value DHmax from dynamic hardnesses at the measurement positions in the longitudinal direction of the elastic component is not greater than 0.20, and the elastic component has a regionin which the dynamic hardness decreases from the edge towards the inside of the elastic component, and in the area where the dynamic hardness decreases, a coefficient of variation of a distance L in the longitudinal direction of the elastic component between the edge and a measurement position located on an inside of the elastic component, when the amount by which the dynamic hardness decreases at two adjacent measurement positions is not greater than 0.04 for the first time, is not greater than 0.28.

[0011] Furthermore, according to at least one aspect of the present disclosure, a process cartridge can be provided which incorporates the cleaning blade of the present disclosure.

[0012] Furthermore, according to at least one aspect of the present disclosure, an electrophotographic image-generating device can be provided which includes the cleaning blade of the present disclosure. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0013] According to the present disclosure, it is possible to obtain a cleaning blade that minimizes the temporary slippage of toner remaining on a cleaning target component, which occurs due to a change in the contact orientation of the cleaning blade relative to the cleaning target component when an electrophotographic image generation operation begins or stops, and which contributes to the stable generation of high-quality electrophotographic images. Furthermore, according to another aspect of the present disclosure, it is possible to obtain a process cartridge and an electrophotographic image generation device that contribute to the generation of high-quality electrophotographic images. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] Fig. Figure 1 shows perspective views of a cleaning blade according to the present disclosure. Fig.Figure 1A shows an example of a cleaning blade of the one-piece molded type. Fig. Figure 1B shows an example of a cleaning blade of the adhesive part type. [ Fig. 2] Fig. Figure 2 is a diagram showing a state in which an edge of the cleaning blade is in contact with a target component when a process cartridge is at rest. The longitudinal direction (X-direction) of the elastic component is a direction perpendicular to the plane of the paper in the drawing. [ Fig. 3] Fig. Figure 3 is a diagram showing a state in which the cleaning blade is in contact with the target component when the process cartridge is in operation. [ Fig. 4] Fig. 4A is a perspective view showing a method for cutting out a measurement sample. Fig. 4B is a side view illustrating a method for cutting out a measurement sample. [ Fig. 5] Fig. Figure 5 is a diagram showing a cut-out of a sample for measuring dynamic hardness in a cross-section perpendicular to the longitudinal direction of the elastic component. [ Fig. 6] Fig. Figure 6 is a diagram showing measurement points for dynamic hardness in a cross-section perpendicular to the longitudinal direction of the elastic component. [ Fig. 7] Fig. Figure 7 is a diagram showing profiles of the dynamic hardnesses measured at the points on a straight line bisecting an angle of the edge in cleaning blades according to Example 1 and Example 3. [ Fig. 8] Fig. Figure 8 are illustrative diagrams showing the state of a precursor impregnated with a hardenable composition. Fig. Figure 8A shows a precursor in which the length of soft segments between meshing points is uniform, and Fig.Figure 8B shows a precursor in which the length of soft segments between meshing points is uneven. DESCRIPTION OF THE EXECUTION FORMS

[0014] In the present disclosure, “from XX to YY” or “XX to YY”, indicating a numerical range, represents a numerical range having a lower bound and an upper bound, which are endpoints unless otherwise specified. In a case where numerical ranges are described in steps, an upper bound and a lower bound of each numerical range may be combined as needed. Furthermore, in the present disclosure, for example, a description such as “at least one selected from the group comprising XX, YY, and ZZ” means a value of XX, YY, ZZ, a combination of XX and YY, a combination of XX and ZZ, a combination of YY and ZZ, or a combination of XX, YY, and ZZ.

[0015] According to the inventors' investigations, it was confirmed that in the electrophotographic device blades and cleaning blades disclosed in PTL 1 to PTL 3, a cured section of the cleaning blade that comes into contact with a cleaning target component provides an effect that improves cleaning performance to a certain degree. However, it was found that in a section of the cleaning target component with which the cleaning blade comes into contact when an electrophotographic image generation operation stops or starts (begins), the toner can locally slip through, and image defects can occur. Therefore, the inventors initiated further investigations to determine the cause of this phenomenon.As a result, it was found that the depth of the surface section of the cleaning blade undergoing the curing treatment is uneven along the blade's length, and that this unevenness leads to an unstable contact orientation of the free end section of the cleaning blade relative to the target component when the electrophotographic image generation process starts or stops. Furthermore, it was found that by using a cleaning blade in which the depth of the surface section undergoing the curing treatment is uniform along its length, the contact orientation of the free end section of the cleaning blade relative to the target component is stabilized when the electrophotographic image generation process starts or stops, thus preventing the aforementioned local toner slippage.

[0016] That is, the cleaning blade according to one aspect of the present disclosure comprises an elastic component and a support component that supports the elastic component. The elastic component has a first surface at a free end section of the elastic component and a second surface which, together with the first surface, forms an edge, wherein, in a cross-section perpendicular to the longitudinal direction of the elastic component and on a straight line bisecting an angle of the edge, when the dynamic hardness is measured at measurement positions 10 µm away from the edge, the coefficient of variation of the maximum value DHmax among the dynamic hardnesses at the measurement positions in the longitudinal direction of the elastic component is 0.20 or less.Furthermore, the elastic component has a region where the dynamic hardness decreases from the edge towards the inside of the component, and in the region where the dynamic hardness decreases, the coefficient of variation of the distance L in the longitudinal direction of the component between the edge and a measurement position located inside the elastic component, when the amount by which the dynamic hardness decreases at two adjacent measurement positions first becomes / is 0.04 or less, is 0.28 or less.

[0017] Examples of cleaning target components in which an electrophotographic cleaning blade according to at least one aspect of the present disclosure (hereinafter simply referred to as a "cleaning blade") is used include image carrier components such as a photosensitive component and endless tapes such as an intermediate transfer tape. An embodiment of a cleaning blade according to at least one aspect of the present disclosure is described in detail below using an image carrier component as an example of a cleaning target component; however, the present disclosure is not limited to this embodiment. <Gestaltung der Reinigungsklinge>

[0018] Fig. 1, Fig. 2 and Fig. Figure 3 shows an example of a cleaning blade.

[0019] Fig.Figure 1 shows a schematic diagram illustrating the design of a cleaning blade. The cleaning blade comprises an elastic component 2 and a support component 3 that supports the elastic component 2. The elastic component has a first surface at a free end section and a second surface that, together with the first surface, forms an edge.

[0020] In the elastic component, preferably either the first surface or the second surface, or both surfaces forming the edge that comes into contact with the target component, are a cured (hardened) surface that contacts the target component. To improve cleaning performance, it is advantageous if a cured area is formed in at least one surface of the first and second surfaces on both sides of the edge of the cleaning blade that comes into contact with the target component, and if this cured area is in contact with the target component and the inner surface near the surface. Fig. 1. The "longitudinal direction" of the cleaning blade is the X-direction, and the "transverse direction" and the "thickness direction" are the Z-direction and the Y-direction, respectively.

[0021] In the cleaning blade, the "free end" of the elastic component is the end of the elastic component opposite the end supported by the support component. Furthermore, the "free end section" of the elastic component is the free end and its surrounding area. The "edge" refers to a contact area of ​​the cleaning blade that comes into contact with the target component and is a burr formed by the first and second surfaces intersecting each other. The "first surface" is, for example, a lower surface 5 or a vertical surface 6 of the elastic component. Fig. 2, and the “second surface” is, for example, a vertical surface 6 or a lower surface 5 of the elastic component in Fig.2. In the following, the lower surface 5 is referred to as the first surface and the vertical surface 6 as the second surface. The free end of the elastic component and its surroundings are referred to as the "tip part" of the elastic component or as the "tip part" of the cleaning blade.

[0022] Fig.Figure 1A shows an example of a cleaning blade in which the elastic component 2 and the support component 3 are formed in one piece. The cleaning blade in this example can be obtained by placing a support component in a mold, then injecting a raw material composition, such as a polyurethane elastomer, into the mold, heating it, allowing it to react and cure, and then removing the mold. After mold removal, if necessary, the tip portion of the free end of the elastic component can be cut off in the Z direction and both ends of the elastic component can be cut off in the X direction. If a step to form a cured area on the free end portion of the elastic component is required, this step can be performed before (separating) or after cutting (separating). This allows the cleaning blade to be obtained in which the elastic component 2 and the support component 3 are integrated.

[0023] Fig. Figure 1B shows an example of a cleaning blade of the adhesive type, obtained by separately forming a plate for the elastic component, subsequently cutting (separating) it into strips to form the elastic component 2, and bonding the elastic component to the support component 3 with an adhesive or the like. Here, a step to form a cured area 4 at the free end section of the elastic component 2 can be performed before or after bonding the elastic component to the support component.

[0024] The length of the cleaning blade in the longitudinal direction is not particularly limited and is, for example, preferably 100 to 500 mm and more preferably 120 to 400 mm.

[0025] In particular, if, for example, the cleaning blade according to one aspect of the present disclosure is a cleaning blade of an electrophotographic image-generating device that can transport A4-format paper in the horizontal direction (landscape format), the length is preferably the entire width of the A4-format paper in the horizontal direction, that is, at least 297 mm or greater. In this case, the upper limit of the length is not particularly restricted and is preferably, for example, 350 mm or less in order to reduce the size of the housing of the electrophotographic image-generating device.If, according to one aspect of the present disclosure, the cleaning blade is a cleaning blade of an electrophotographic image-generating device capable of transporting A3-format paper in the horizontal direction, the length is preferably the entire width of the A3-format paper in the horizontal direction, that is, 420 mm or greater. In this case, the upper limit of the length is not particularly restricted and is preferably, for example, 480 mm or less, in order to reduce the size of the housing of the electrophotographic image-generating device. That is to say, for example, it is preferably 297 to 350 mm and particularly preferably 420 to 480 mm.

[0026] If, according to one aspect of the present disclosure, the cleaning blade is used in an electrophotographic image-generating device that can transport larger recording material (with a larger format), its length in the longitudinal direction is not limited to what has been described above. [Supporting component]

[0027] The material that forms the supporting component of the cleaning blade is not particularly limited, and examples include the following materials: Metal materials such as sheet steel, stainless steel sheet, galvanized sheet steel and chromium-free sheet steel, as well as resin materials such as 6-nylon and 6,6-nylon.

[0028] Furthermore, the shape and structure of the supporting component are not particularly restricted. For example, as in Fig. 2 and the like, shown, one end of the elastic component of the cleaning blade is supported by the support component. [Elastic component][Depth (spacing, distance) of the cured area]

[0029] The elastic component has a region where the dynamic hardness decreases from the edge towards the inside of the elastic component when measured at positions 10 µm from the edge along a straight line that bisects the angle of the edge in a cross-section perpendicular to the longitudinal direction of the elastic component. Furthermore, in this region of decreasing dynamic hardness, the distance between the edge and the measurement position located on the inside of the elastic component, when the decrease in dynamic hardness at two adjacent measurement positions first becomes 0.04 or less, is L.

[0030] The arrangement for providing such a region in the elastic component is not particularly limited, and examples include a method for providing a cured region formed by impregnating a free end section of a precursor of an elastic component with a curable composition and subsequently curing the curable composition. Here, the precursor of the elastic component is a component before it is impregnated with the curable composition (hereafter referred to simply as a "precursor").

[0031] Here, the dynamic hardness, used as the hardness of the elastic component, is a hardness value in which the cured area can be measured with higher sensitivity. Therefore, when measuring at 10 µm intervals in the area where the dynamic hardness decreases, the distance L between the edge and the measurement position located within the elastic component can be considered the boundary between the area where the hardness is increased due to the formation of the cured area and the area not impregnated with the curable composition, where the hardness is not increased. This distance L can be determined when the amount by which the dynamic hardness decreases at two adjacent measurement positions first becomes 0.04 or less.That is, the distance L can also be defined as the distance (the depth) from the edge of the elastic component to the tip (the end) of its interior, where the curing treatment is still applied (occurs).

[0032] When the electrophotographic image-generating device is in operation, a state arises in which the cleaning blade comes into contact with the target component and the tip part (end part) of the free end section 4 bends / deforms slightly, as shown in Fig.Figure 3 illustrates this. The extent of the deformation of the elastic component is likely influenced by the contact orientation of the entire cleaning blade, which comprises the contact area. That is, if the distance L is small, it is easier to form a contact orientation that encompasses the entire elastic component, since the area where the hardness is not increased is closer to the contact area. Therefore, it becomes easier to operate when the extent of the deformation is relatively large. Conversely, if the distance L is large, it is difficult to form a contact orientation that encompasses the entire elastic component, since the area surrounding the contact zone consists only of the hardened area. Therefore, it becomes easier to operate when the deformation is relatively small.

[0033] For the reason stated above, the distance L is preferably 500 µm or less, and more preferably 300 µm or less. Setting the distance L to 500 µm or less allows for better maintenance of the damping performance of the elastic component. Furthermore, the lower limit of the distance L is not particularly restricted and is preferably 20 µm or greater, and more preferably 40 µm or greater, as this simplifies maintaining the contact gap width and improves cleaning performance. For example, the range of the distance L is preferably 20 to 500 µm, and particularly preferably 40 to 300 µm.

[0034] In the elastic component according to one aspect of the present disclosure, the coefficient of variation of the distance L in the longitudinal direction is small. In particular, the coefficient of variation of the distance L in the longitudinal direction of the elastic component is 0.28 or less. The coefficient of variation of the distance L is preferably 0.25 or less. The lower limit of the coefficient of variation of the distance L is not particularly limited and is usually 0.00 or greater, and may be 0.02 or greater or 0.04 or greater. For example, the range of the distance L is preferably between 0.00 and 0.28, particularly preferably between 0.02 and 0.28, and even more preferably between 0.04 and 0.25.

[0035] It is assumed that if the coefficient of variation of the distance L in the longitudinal direction lies within the range mentioned above, the deformation (bending, deflection) of the elastic component can occur uniformly in the longitudinal direction. The inventors found that it takes time for the electrophotographic imaging device to start an imaging operation from a standstill state and for the contact state of the elastic component to stabilize with respect to the target component being cleaned if the area of ​​large deformation (bending, deflection) and the area of ​​small deformation (bending, deflection) are adjacent to each other in the longitudinal direction of the elastic component.They found that in an unstable contact condition at the boundary between the area of ​​high deformation (bending, deflection) and the area of ​​low deformation (bending, deflection), the cleaning blade is unable to exert sufficient contact force on the target component, causing the toner to slip.

[0036] Furthermore, they found that even when the electrophotographic imaging device stops the imaging operation, if the coefficient of variation of the distance L in the longitudinal direction of the elastic component is large, the area where the deformation is large and the area where the deformation is small exist (lie) next to each other in the longitudinal direction of the elastic component, and sufficient contact force cannot be exerted at the boundary between the area of ​​large deformation and the area of ​​small deformation, causing the toner to slip through.

[0037] The following describes a method for measuring the coefficient of variation of the distance L in the longitudinal direction of the elastic component.

[0038] The inventors discovered that to avoid the condition in which the area with large deformation (bending, deflection) and the area with small deformation (bending, deflection) exist side by side in the longitudinal direction, it is effective to make the depth of the hardened area in the longitudinal direction of the cleaning blade and the coefficient of variation of the distance L within the said area uniform.

[0039] As at least one method for obtaining an elastic component in which the coefficient of variation of the distance L lies within the specified range, a method can be cited in which at least one surface of a polyurethane-comprising precursor, selected from the group comprising one surface corresponding to the first surface and one surface corresponding to the second surface of the elastic component, is impregnated with a curable composition and the curable composition is cured. Here, it is advantageous in the above-mentioned method to use a polyurethane-comprising precursor in which the length of the soft segments present between the crosslinking points is uniform.

[0040] The elastic component is preferably a hardened product obtained by impregnating at least a part of at least one surface (area) of the precursor of the elastic component, selected from the group comprising an area corresponding to the first surface (area) and an area corresponding to the second surface (area) of the elastic component, with a hardenable composition and hardening the hardenable composition.

[0041] The curable composition penetrates the precursor through spaces in the polyurethane polymer chains, for example, spaces between crosslink points. In this case, by standardizing the lengths of the soft segments between the crosslink points, the distance of the curable composition from the surface of the precursor can be standardized. That is, as in Fig.Figure 8A schematically illustrates that if the distance between the soft segment sections between crosslinking points 801 of a polyurethane in a precursor 807 is uniform, the impregnation tip 805 of the curable composition 803 on the inside (within the precursor) is uniform in the longitudinal direction when the precursor is impregnated from the surface with a curable composition 803. That is, the coefficient of variation of the distance L tends to be small.

[0042] On the other hand, as in Fig. Figure 8B shows that when a precursor 800, in which the length of the soft segments between the crosslinking points 801 is uneven, is impregnated with the curable composition 803 from the surface, the impregnation tip 805 is uneven in the longitudinal direction. That is, the coefficient of variation of the distance L tends to be large.

[0043] The material contained in the curable composition, which forms hardened areas, tends to aggregate (accumulate) around crystal components in the elastic component within the precursor due to hydrogen bonding or similar mechanisms. Consequently, the material impregnated into the precursor, intended to form hardened areas, prevents impregnation if the impregnation occurs near the crystal component. As a result, if a hardened area is formed with a large impregnation depth, for example, a distance L greater than 20 µm, the coefficient of variation of the distance L tends to be large.

[0044] Due to the impregnation mechanism described above, the coefficient of variation of the distance L can be reduced depending on the characteristics of the precursor. [Hardness of the cured area]

[0045] As described above, the elastic component has a region where the dynamic hardness decreases from the edge towards the inside of the elastic component when the dynamic hardness is measured at positions 10 µm away from the edge along a straight line that bisects the angle of the edge in a region perpendicular to the longitudinal direction of the elastic component. Here, the maximum value of the dynamic hardness at the measurement positions is DHmax (kgf / m). 2 In this case, the coefficient of variation of DHmax in the longitudinal direction of the elastic component is 0.20 or less. Furthermore, a smaller coefficient of variation is preferable, and 0.18 or less is even more advantageous. The lower limit is not particularly restricted and is usually 0.00 or more, and may be 0.02 or greater, or 0.04 or greater. For example, it is preferably 0.00 to 0.20, 0.02 to 0.20, or 0.04 to 0.18.

[0046] The device for determining the coefficient of variation of DHmax in the longitudinal direction of the elastic component within the aforementioned range is not particularly limited, and examples include the formation of a cured region in a precursor into which the curable composition can readily penetrate. As described above, examples of such precursors include polyurethanes with high molecular mobility of soft and hard segments. As another example, a precursor in which the spacing between the crosslinking points of the soft segments is uniform and the number of nurates and crystals is low is subjected to an impregnation treatment with a curable composition.

[0047] As described above, achieving the effects of this disclosure requires ensuring that the dynamic hardness of the elastic component is uniform in the longitudinal direction and that the impregnation depth is uniform. If the coefficient of variation of the dynamic hardness in the longitudinal direction is large, that is, if the variation in dynamic hardness in the longitudinal direction is large, it is difficult to obtain the effects of this disclosure. Therefore, it is advantageous if the coefficient of variation of DHmax in the longitudinal direction of the elastic component lies within the range mentioned above.

[0048] Particularly when the coefficient of variation of DHmax is large, even if the coefficient of variation of the distance L in the longitudinal direction of the elastic component is small, the region where the distortion of the contact orientation is large and the region where the distortion of the contact orientation is small can coexist in the longitudinal direction of the elastic component. As a result, when the electrophotographic imaging device starts an imaging operation from a standstill, it takes some time for the contact orientation of the cleaning blade relative to the target component to stabilize and for the deformed state of the elastic component to stabilize.If the condition is unstable, the required contact force cannot be applied at the boundary between the area of ​​high distortion and the area of ​​low distortion in the longitudinal direction of the elastic component, causing the toner to slip.

[0049] If the maximum value DHmax of the dynamic hardness is small, the extent of deformation of the elastic component increases, and the entire elastic component has a bent contact orientation. If the maximum value DHmax of the dynamic hardness is large, because the extent of deformation of the elastic component is small, the entire elastic component has a contact orientation with low deflection.

[0050] This means that the average value of the maximum value DHmax of the dynamic hardness in the longitudinal direction of the elastic component is preferably 0.26 to 3.00 kgf / m². 2 and even more preferably 0.28 to 2.82 kgf / m² 2 . [Method for measuring dynamic hardness]

[0051] Dynamic hardness is measured using the following method. The measuring instrument used is the "Shimadzu Dynamic Ultra Microhardness Tester DUH-W211S" (commercially available from Shimadzu Corporation). A 115° triangular pyramid indenter is used, and the dynamic hardness is determined using the following formula. Dynamic hardness (kgf / m2): DH=α×P / D2

[0052] In this formula, α denotes a constant that depends on the shape of the indenter, P denotes a test force (mN) and D denotes the extent of the indenter's penetration depth into the sample (penetration depth) (µm).

[0053] The measurement conditions are as follows. a: 3.8584 P: 1.0 mN Load rate: 0.03 mN / s. Hold time: 5 seconds Measurement environment: Temperature 23 °C and relative humidity 55% Aging of the sample: Leave for 6 hours or longer in an environment with a temperature of 23 °C and a relative humidity of 55%.

[0054] One procedure for preparing a measurement sample is as follows. If the length of the elastic component in the longitudinal direction is LE, the measurement samples are taken from the centers (16 points, PL1, PL2, ..., ..., PL1). 16 ) of 16 line segments of length LE / 16, obtained by dividing the elastic component into 16 equal parts in the longitudinal direction, with a size of 4 mm in the longitudinal direction (2 mm in both longitudinal directions from the center point), 2 mm from an edge 7 in the transverse direction and 2 mm in the thickness direction (see Fig. 4A and Fig. 4B) cut out.

[0055] The dynamic hardness of the elastic component is measured by positioning the sample so that the indenter strikes the surface (the first surface and the second surface) of the sample perpendicularly at a position 2 mm from the end in the longitudinal direction and 100 µm to 500 µm from the edge in the transverse or thickness direction. An enlarged view of Fig. 4A is a view in which the sample is arranged such that the intruder hits the second surface (surface) of the sample perpendicularly.

[0056] If the dynamic hardness is measured at measuring positions 10 µm away from the edge on a straight line that bisects the angle of the edge in a cross-section perpendicular to the longitudinal direction of the elastic component, the presence of a region where the dynamic hardness decreases from the edge to the inside of the elastic component is measured by the following procedure.

[0057] 16 cut-out test specimens (cut-out test specimens) are cut out at a position of 2 mm in the longitudinal direction, and each test specimen is arranged so that the indenter hits the cut surface perpendicularly (see Fig. 5) The measurement positions are positions on a straight line that bisects the angle of the edge and are located at intervals of 10 µm from the edge (see Fig.6) The measurement is performed sequentially at these positions, and the measurement is continued until a measurement position is reached where the amount by which the dynamic hardness decreases at two adjacent measurement positions is 0.04 or less for the first time. This confirms the presence of a region where the dynamic hardness decreases from the edge towards the inside of the elastic component. Furthermore, the distance between the edge and the measurement position within the elastic component where the amount by which the dynamic hardness decreases at two adjacent measurement positions is 0.04 or less for the first time is defined as the distance L. Additionally, the maximum value of the dynamic hardness at the measurement positions is DHmax.

[0058] The upper measurement is performed on 16 test specimens, and the coefficient of variation of the distance L in the longitudinal direction of the elastic component and the coefficient of variation of the maximum value DHmax of the dynamic hardness in the longitudinal direction of the elastic component are calculated. Here, the coefficient of variation is calculated using the following formula (1). Coefficient of variation = Standard deviation / Average value

[0059] Examples of materials that form the precursor to the elastic component of the cleaning blade are listed below. The elastic component can therefore comprise the following materials.

[0060] Polyurethane elastomers and ethylene propylene diene monomer (EPDM) copolymer rubber, acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), fluorocarbon rubber, silicone rubber, epichlorohydrin rubber, NBR hydride, polysulfide rubber, and the like. Among these, it is preferable to include a polyurethane, and even more so, a polyurethane elastomer composed of hard and soft segments. A polyester urethane elastomer is preferable as a polyurethane elastomer due to its excellent mechanical properties.

[0061] Polyurethane elastomer is a material that is mainly obtained from raw materials (substances) such as polyisocyanate, polyol, chain extenders, catalysts and other additives.

[0062] These raw materials are described in detail below.

[0063] A polyisocyanate can be defined as a compound that has two or more isocyanate groups in the molecule, and examples include the following substances: 4,4'-Diphenylmethane diisocyanate (4,4'-MDI), polymethylenepolyphenylene polyisocyanate (polymeric MDI), 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene 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), carbodiimide-modified MDI, and polymethylenephenyl polyisocyanate (PAPI).

[0064] Among these, 4,4'-MDI is preferable because it yields a polyurethane elastomer with excellent mechanical properties.

[0065] Examples of polyols include the following substances: 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-based polyols obtained by ring-opening polymerization of caprolactone; polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; and polycarbonate diol. These can be used alone or in combination with two or more.

[0066] Among polyols, a polyester polyol with adipate is preferable, as this results in a polyurethane elastomer with excellent mechanical properties. A polyester polyol with butylene adipate is particularly preferable.

[0067] A substance that can lengthen polyurethane elastomer chains, such as glycols and trihydric or higher polyhydric alcohols, can be used as a chain extender.

[0068] Examples of substances containing 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.

[0069] Examples of trihydric or higher polyhydric alcohols include trimethylolpropane, glycerol, pentaerythritol, and sorbitol. These can be used alone or in combination with two or more. These trihydric or higher polyhydric alcohols are preferably used as crosslinking agents. Among the polyhydric alcohols, trimethylolpropane is particularly preferred.

[0070] Catalysts commonly used for curing polyurethane elastomers can be employed as catalysts. These include tertiary amine catalysts, such as the following amino alcohols: 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-based compounds; and triazine-based compounds. Organometallic acid salts such as potassium acetate and potassium alkyl octolate can also be used. Additionally, metal catalysts commonly used for urethanization, such as dibutyltin dilaurate, can be employed. These can be used alone or in combination with one or more.

[0071] N,N'-Dimethylhexanolamine is the preferred catalyst. Examples of commercially available catalysts include Kaolizer No. 25 (product name, available from Kao Corporation). This catalyst is suitable for promoting urethanation over nurate formation. Since it also has an OH group at its end, it acts as a catalyst while simultaneously participating in the reaction and being internally absorbed, thus reducing the possibility of chemical attack due to exudation. Furthermore, it is also preferable due to its favorable reactivity. An ethylene glycol solution of potassium acetate is also preferable. Examples of commercially available products include POLYCAT46 (product name, available from Air Products Japan, KK).

[0072] For example, the polyurethane elastomer is preferably a reaction product of a mixture comprising at least one polyol selected from the group consisting of polyester polyol and polyether polyol, a trihydric or higher polyhydric alcohol and 4,4'-MDI.

[0073] For example, the polyurethane elastomer is preferably a reaction product of a mixture comprising at least one polyol selected from the group comprising polyester polyol and polyether polyol, a polyisocyanate having 4,4'-MDI, and a trihydric or higher alcohol.

[0074] In the components of the mixture, which serve as a raw material for the polyurethane elastomer, the polyol content is preferably 50 to 80 percent by mass and more preferably 55 to 70 percent by mass.

[0075] In the components of the mixture, which serve as a raw material for the polyurethane elastomer, the polyisocyanate content is preferably 15 to 50 percent by mass and more preferably 25 to 40 percent by mass.

[0076] In the components of the mixture, which serve as a raw material for the polyurethane elastomer, the content of the trivalent or higher-hydraulic polyhydric alcohol is preferably 3 to 15 percent by mass and more preferably 5 to 10 percent by mass.

[0077] If necessary, additives such as a pigment, a plasticizer, an impregnating agent, an antioxidant, a UV absorber and a light stabilizer can be added to the raw material that forms the precursor.

[0078] Although the details are described below, if the precursor comprises a polyurethane and the molecular mobility of the soft and hard segments is higher, the curable composition tends to readily penetrate the precursor during the manufacturing process of the elastic component. As a result, the coefficient of variation of DHmax in the longitudinal direction of the elastic component and the coefficient of variation of the distance L in the longitudinal direction of the elastic component can be easily adjusted to the desired values.

[0079] In the present disclosure, the hard segment is a component with low molecular mobility at or near crosslinking points, such as crystalline components formed by the aggregation of urethane bonds, nurate bonds, polymeric MDI, and trimethylolpropane. Furthermore, the soft segment is a segment with high molecular mobility between crosslinking points.

[0080] The molecular mobility of the hard segments decreases when the proportion of stiff components such as nurate bonds in the polyurethane, crosslinking sections originating from polymeric MDI, and the crystal structure formed by the interaction between soft segments is increased, and decreases when the crosslinking points are made flexible.

[0081] To increase the molecular mobility of the hard segments, it is therefore advantageous to minimize the use of polymeric MDI as a raw material for the polyurethane, and it is particularly advantageous to avoid its use altogether. Furthermore, to prevent the formation of crystalline components due to the interaction of the soft segment section, it is advantageous to use trimethylolpropane (TMP) as a crosslinking component. When a TMP-derived crosslinked structure is introduced into the polyurethane, the steric hindrance of the TMP-derived crosslinked structure makes it less likely that the soft segment sections present between the crosslinked structures will interact with each other. As a result, the formation of the crystalline structure (crystalline component) due to the interaction between soft segments, i.e., the formation of hard segments, is prevented.

[0082] Since trimethylolpropane has a methylene backbone adjacent to a hydroxyl group, a cross-linked structure with a flexible molecular structure is formed. As a result, according to one aspect of the present disclosure, the polyurethane likely exhibits higher molecular mobility of the hard segments than a polyurethane with a rigid cross-linked structure derived from polymeric MDI.

[0083] The molecular mobility of soft segments and hard segments can be evaluated by measuring the spin-spin relaxation time T2 (lateral relaxation time) in pulsed NMR using a measurement sample described below.

[0084] In pulse NMR measurements of a polyurethane elastomer in an environment at 50 °C, when the polyurethane elastomer is / is separated into two components, a hard segment and a soft segment, the spin-spin relaxation time (T2) is L) of the soft segment preferably 250 to 320 µs.

[0085] If the molecular mobility of the soft segments is high, relaxation takes longer, so the spin-spin relaxation time (T2) increases. L ) of the soft segment increased.

[0086] The spin-spin relaxation time T2 is measured using a solid-echo technique with a pulse NMR device.

[0087] The pulsed NMR instrument is used to evaluate the mobility of polymer molecules, such as rubber, based on the mobility (relaxation time) of hydrogen atoms in the molecular chains. In the present embodiment, the solid-echo technique is used as the sequence. The solid-echo technique itself, using a pulsed NMR instrument, is not particularly limited, and known methods can be employed.

[0088] If the spin-spin relaxation time T2 of the elastic component of the cleaning blade is measured by a pulse NMR measurement, a T2 relaxation curve (free induction decay curve) is obtained.

[0089] The following describes a specific measuring device.

[0090] If T2 L If the curing time is less than 250 µs, the molecular mobility of the soft segments is insufficient, and the curable composition does not readily penetrate the precursor. However, if T2 L If the 320 µs value is exceeded, the tip of the elastic component is more likely to move excessively due to the high molecular mobility of the soft segments, allowing toner and external additives to slip through more easily.

[0091] T2 L is preferably 260 µs or greater, and even more preferably 270 µs or greater. Furthermore, T2 Lpreferably 310 µs or less, and even more preferably 300 µs or less. For example, T2 L preferably in a range of 260 to 310 µs or 270 to 300 µs.

[0092] T2 L T2, which is an index for the molecular mobility of soft segments, can be controlled by the crosslinking density. When the crosslinking density is higher, the molecular weight between the crosslink points is smaller, the size of the space in which the soft segments can move freely is smaller, and thus the molecular mobility decreases. As a result, T2 decreases. L Furthermore, it is also effective to standardize the lengths of the soft segments between the crosslinking points in order to minimize the molecular mobility of the soft segments.

[0093] To obtain a polyurethane in which the distance between crosslinking points is short and the length between the crosslinking points is uniform, it is, for example, preferred to specify the average (number-average) molecular weight of the prepolymer as a raw material for the polyurethane within a range of 8000 to 12000 and to minimize the use of a chain extender such as 1,4-butanediol, with it being particularly advantageous to use no chain extender at all. That is to say, the polyurethane is preferably a reaction product of a mixture comprising a prepolymer having an average (number-average) molecular weight of 8000 to 12000 and a curing agent.

[0094] Here, the urethane prepolymer is a polymer obtained by reacting a polyol with a polyisocyanate. The urethane prepolymer has at least one isocyanate group and a polyether structure. In the following, the urethane prepolymer will simply be referred to as a prepolymer.

[0095] Furthermore, the average (number-average) molecular weight of the prepolymer can be adjusted by changing the average (number-average) molecular weight of the polyol used as a raw material for the prepolymer or the type of polyisocyanate.

[0096] Here is an example of conditions for measuring the average (number-average) molecular weight of the prepolymer as follows.

[0097] Device: HLC-8320GPC (product name, commercially available from Tosoh Corporation) Column: TSKgel SuperMultiporeHZ-N (product name, commercially available from Tosoh Corporation; 4.6mm ID × 15cm) Eluent: THF Flow rate: 0.35 ml / min Sample: 0.5 wt% THF solution Injection volume: 10 µl Detector: RI Temperature: 40 °C Standard substance: Polystyrene

[0098] Furthermore, in pulse NMR measurements of a polyurethane elastomer in an environment at 50 °C, when the polyurethane elastomer is separated into two components, a hard segment and a soft segment, the T2 relaxation time (T2) is S ) of the hard segment preferably 52 to 85 µs.

[0099] If T2 S If the T2 value is 52 µs or greater, the molecular mobility of the hard segments is sufficient, and the curable composition penetrates the precursor more readily. SIf the molecular mobility of the hard segments is 85 µs or less, it is not too high, which can prevent excessive movement of the tip of the elastic component and more effectively prevent the slippage of toner and external additives. <Molekulare Mobilität des harten Segments>

[0100] The molecular mobility of the hard segments is influenced by rigid components within the molecule. These rigid components are nurates and crystals, and reducing their amount can increase the molecular mobility of the hard segments. Therefore, minimizing the number of nurate bonds and increasing the urethane content is advantageous. Details are as follows.

[0101] In an FT-IR measurement of a polyurethane elastomer using diamond as an ATR crystal, the value of the ratio of peak intensity at 1415 cm⁻¹ is -1to the peak intensity at 1538 cm -1 (peak intensity at 1415 cm -1 / peak intensity at 1538 cm -1 ) preferably 0.50 to 0.65.

[0102] In the FT-IR analysis of a polyurethane elastomer using diamond as an ATR crystal, the peak value is 1415 cm⁻¹. -1 a peak value corresponding to the isocyanurate ring. The peak value is at 1538 cm. -1 In contrast, this is a peak value that corresponds to the NH bending angle of the urethane bond. That is, if the value is based on the peak intensity at 1415 cm⁻¹ -1 / peak intensity at 1538 cm -1 If the value is in the range of 0.50 to 0.65, this indicates that the number of nurate bonds in the polyurethane elastomer is low.

[0103] If the value is from the peak intensity at 1415 cm -1 / peak intensity at 1538 cm -1If the peak intensity ratio is greater than 0.65, this indicates that the polyurethane elastomer contains a large number of nurate bonds. Therefore, the molecular mobility of the hard segments is reduced due to the stiffness of the nurate bonds, and the curable composition does not easily penetrate the precursor. Conversely, if the peak intensity value is greater than 1415 cm⁻¹, this indicates that the polyurethane elastomer contains a large number of nurate bonds. -1 / peak intensity at 1538 cm -1 If the molecular mobility of the hard segments is less than 0.50, it tends to become too large, which is why the value is preferably between 0.50 and 0.65. The value is based on the peak intensity at 1415 cm⁻¹. -1 / peak intensity at 1538 cm -1 preferably 0.53 to 0.65.

[0104] To determine the peak intensity value at 1415 cm -1 / peak intensity at 1538 cm -1To define the specific range mentioned above, a method for reducing the number of nurate bonds and generating a high urethane content can be used. Specific examples of this involve using a urethanization catalyst while avoiding a catalyst that promotes the formation of nurates. This includes approximating the mixing ratio of -NCO and -OH in the prepolymer to approximately 1 and setting the reaction temperature at 100 °C or lower when reacting with prepolymer materials.

[0105] The polyurethane can incorporate a rigid structure, such as polymeric MDI, as a single component. The details are as follows.

[0106] The elastic component preferably has a plate shape at least at its free end, with a main surface (e.g., a first surface) facing the target component and a tip surface (e.g., a second surface) that, together with the main surface, forms an edge. Here, the polyurethane elastomer comprising the precursor of the elastic component is heated to 1000 °C at a rate of 10 °C / s using a direct sample feeder mass spectrometer. This mass spectrometer heats and vaporizes a sample comprising the polyurethane elastomer in an ionization chamber, thereby ionizing the sample molecules. The total quantity of all ions detected as a result is M1, and the integrated intensity of the peak values ​​in the extracted ion thermogram, derived from the polymeric MDI and corresponding to an m / z range of 380.5 to 381.5, is M2. In this case, M2 / M1 is preferably less than 0.0010.

[0107] The following methods, for example, can be used to determine the physical properties of the polyurethane elastomer comprising the precursor of an elastic component. Specifically, on a line bisecting the angle of an edge formed by the first and second surfaces of the elastic component, a section of the elastic component positioned inwards by a distance L from the edge is not impregnated with the curable composition. Therefore, the polyurethane elastomer comprising this section can be considered equivalent to the polyurethane elastomer comprising the precursor.

[0108] Thus, a measurement sample is prepared (formed) by removing the area in which the dynamic hardness decreases (cured area) from the elastic component, whereby the subsequent measurement is carried out using the measurement sample and thus M2 / M1 of the polyurethane elastomer comprising the precursor can be measured.

[0109] When a test specimen is prepared (formed), the area where the dynamic hardness decreases extends to a depth of a distance L from the edge along a straight line bisecting the edge of the elastic component. Therefore, a specimen obtained by removing an area from each surface (area) of the elastic component to, for example, at least a depth of L × 1.4, can be used as the test specimen. For example, the area obtained by removing an area from the tip surface of the elastic component to a depth of L × 1.4 is referred to as the area corresponding to the tip surface of the elastic component, and the area obtained by removing an area from the main surface of the elastic component to a depth of L × 1.4 is referred to as the area corresponding to the main surface of the elastic component.In this case, an area corresponding to the tip surface of the elastic component and an area corresponding to the main surface of the elastic component form an edge A.

[0110] In the measurement setup, a third line segment is assumed to be drawn parallel to edge A at a distance of 0.5 mm from the tip of the elastic component on the surface corresponding to the tip area. The length of this third line segment is L', and the points 1 / 8L', 1 / 2L', and 7 / 8L' from an end face on the third line are P0', P1', and P2'. Samples taken at P0', P1', and P2' are heated to 1000 °C at a rate of 10 °C / s using a direct sample feeder mass spectrometer, which heats and vaporizes a sample in an ionization chamber, thereby ionizing the sample molecules. If the quantity of all detected ions obtained as a result is M1 and the integrated intensity of the peaks in the extracted ion thermogram, derived from the polymeric MDI and corresponding to an m / z value range of 380.5 to 381.5, is M2, then M2 / M1 of the polyurethane elastomer can be calculated.

[0111] As the isocyanate, it is preferable to use 4,4'-MDI, which has high reactivity and in which two isocyanate groups have the same reactivity. On the other hand, as described above, it is preferable to minimize the use of polymeric MDI, which is a trifunctional MDI, and it is particularly preferable to avoid its use altogether. In particular, M2 / M1 is preferably less than 0.0010. If M2 / M1 is within the specific range mentioned above, the molecular mobility of the soft segments will be sufficient, and the curable composition will readily penetrate the precursor.

[0112] M2 / M1 is preferably 0.0009 or less. A smaller M2 / M1 value is preferable, wherein the lower limit of M2 / M1 is not particularly restricted and is preferably 0.0000 or greater.

[0113] If M2 / M1 is 0.001 or greater, the molecular mobility of the soft segments is insufficient due to the stiffness of the polymeric MDI, and the curable composition does not easily penetrate the precursor.

[0114] To increase the molecular mobility of the hard segments, it is also advantageous to minimize the number of crystal structures. In particular, it is beneficial to minimize the amount of materials that tend to form crystal structures, such as 1,4-butanediol, and to make the crosslinking agent, such as trimethylolpropane, more abundant. The crosslinking agent, such as trimethylolpropane, facilitates the maintenance of the spacing between the urethane bonds and hinders the formation of the crystal structure. <Molekulare Mobilität des weichen Segments>

[0115] The molecular mobility of soft segments is readily influenced by the distance between the crosslinking points and the structure between these points. Therefore, for example, the molecular mobility of soft segments can be reduced by shortening the distance between the crosslinking points and increasing the ester group concentration of the polyol.

[0116] Examples of methods for reducing the distance between crosslinking points involve increasing the concentration of the crosslinking agent in the raw material composition of the elastic component. The distance between the crosslinking points depends on the ester group concentration and is preferably about 6000 to 9000 g / mol. The concentration of the crosslinking agent in the raw material composition of the elastic component is preferably 0.30 to 0.70 mmol / g, more preferably 0.40 to 0.61 mmol / g, and most preferably 0.50 to 0.60 mmol / g, taking into account the molecular mobility of the rigid segments.

[0117] The procedure for calculating the concentration of the crosslinking agent is described below. Quantification can be performed, for example, by pyrolysis-GC / MS.

[0118] The polyhydric alcohol is detected by pyrolysis-GC / MS. The measurement conditions are as follows.

[0119] Device (equipment): Pyrolysis device: EGA / PY-3030D (product name, commercially available from Frontier Laboratories Ltd.) Gas chromatography instrument: TRACE1310 Gas chromatography (product name, Thermo Fisher Scientific) Mass spectrometer: ISQLT (product name, Thermo Fisher Scientific) Pyrolysis temperature: 500 °C GC column: Inner diameter 0.25 mm × 30 m stainless steel capillary column. Stationary phase 5% phenylpolydimethylsiloxane. Heating conditions: Held at 50 °C for 3 minutes and heated to 300 °C at 8 °C / min MS condition: Mass number range m / z = 10 to 650 Sampling rate: 1 second / sample

[0120] The type of polyhydric alcohols is determined using GC / MS. A calibration curve is generated based on GC analysis of qualified polyhydric alcohol types with known concentrations, and quantification is performed based on the GC peak range ratio, while the concentration of the crosslinking agent in the raw material composition is calculated.

[0121] Furthermore, it is advantageous if the spacing between the crosslink points of the soft segments is as uniform as possible. If the spacing between the crosslink points is uneven, the molecular mobility of the entire precursor tends to vary. For example, some components with high molecular mobility can lead to excessively high molecular mobility in the soft segments, while some components with low molecular mobility can lead to insufficient molecular mobility in the soft segments, preventing the curable composition from easily penetrating the precursor. To ensure sufficient molecular mobility in the soft segments, it is therefore advantageous to have few rigid components, many crosslinks, and uniform spacing between the crosslink points.The method for standardizing the distance between crosslinking points is not limited, and examples include a process for producing a polyurethane by a prepolymer process using a prepolymer that has the most uniform molecular weight distribution possible. It is preferable to use a simple material composition with a uniform molecular weight so that the molecular weight distribution is uniform, and it is preferable to minimize the use of a chain extender such as glycol, which tends to make the molecular weight distribution uneven.

[0122] In this case, the average (number-average) molecular weight of the prepolymer is preferably 8,000 to 12,000. The molecular weight can be analyzed by GPC using the method described above.

[0123] In the elastic component, the angle of the edge formed by the first surface and the second surface is not particularly limited and is usually about 85 to 95 degrees.

[0124] Furthermore, the international rubber hardness grade (IRHD) of the elastic component is preferably 60 degrees or greater, and more preferably 65 degrees or greater. The upper limit is not particularly restricted and may be 90 degrees or less, or 85 degrees or less. Preferably, for example, it is 60 to 90 degrees or 65 to 85 degrees. [Location of the hardened area]

[0125] When a cured area forms in the elastic component, the location of the cured area formation is preferably arranged on at least one surface of the first and second surfaces that are brought into contact with a target component 8, and on the inner side near the surface, to improve cleaning performance. If the target component is a photosensitive component, the imaging area on the surface of the photosensitive component is brought into contact with the edge of the cleaning blade and cleaned. In this case, the non-cleaning component rotates in the direction R.

[0126] The hardened area can also be located on a surface other than the first and second surfaces at the tip of the elastic component, that is, the surface facing the first surface (in Fig.2 (surface designated with reference numeral 10) and two end surfaces of the elastic component in the longitudinal direction (in Fig. 1. Surfaces designated with reference numeral 9). In this case, the stiffness of both surfaces of the elastic component can be improved and the extent of deformation of the cleaning blade can be further reduced. [Method for forming a hardened area]

[0127] The method for forming a cured area in the elastic component is not particularly limited, and examples include applying a curable composition comprising a material for forming a cured area to an area where high hardness is desired and curing it. That is to say, it is preferable for the elastic component to be impregnated with a cured product of the curable composition. The curable composition is used diluted with a thinner as required and can be applied by known means such as dipping, spraying, using a dispenser, brushing, or roller application. An isocyanate compound, as described below, can be used as the material for forming the cured area. Furthermore, the curable composition preferably comprises a polymerization initiator.

[0128] To form a cured area on the inside of the elastic component and not on its surface, the precursor of the elastic component must be sufficiently impregnated with a curable composition comprising a material for forming a cured area (such as an isocyanate compound). Since impregnation is promoted by reducing the viscosity of the curable composition, it is effective to dilute or heat the curable composition, or to apply both in combination. The material temperature is preferably 40 °C or higher and preferably 120 °C or lower. The temperature is preferably, for example, 40 to 120 °C.

[0129] The process for impregnating the precursor with the curable composition and subsequently curing the curable composition is not particularly restricted, and examples include heat treatment and treatment using ultraviolet light emission. Of these, heat treatment is preferable to adequately form the cured area on the inside of the elastic component. The heat treatment conditions are described below.

[0130] When a treatment is performed by ultraviolet light emission, a light source that generates ultraviolet light is used in the step of forming the cured area. In particular, the wavelength of the maximum emission peak is preferably close to 254 nm, for example, within a range of 254 ± 1 nm. If multiple ultraviolet light emission peaks are present, one of the emission peaks is preferably located close to 254 nm.

[0131] The intensity of light emitted by a light source is not particularly limited, and values ​​measured using a spectroradiometer (USR-40V / D, commercially available from Ushio Inc.) and an accumulated UV intensity meter (UIT-150-A, UVD-S254, VUV-S172, VUV-S365, commercially available from Ushio Inc.) can be used. Furthermore, the cumulative amount of ultraviolet light can be appropriately selected according to the extent of the cured area formation. The cumulative amount of light can be adjusted by the emission time of the light from a light source, the power of the light source, the distance from the light source, or similar factors, and can, for example, be determined to achieve a desired cumulative amount of light of, say, 100 J / m². 2 will be received.

[0132] The cumulative amount of ultraviolet light emitted onto a conductive component can be calculated, for example, using the following method. Cumulative amount of ultraviolet light (mJ / cm²) = Intensity of ultraviolet light (mW / cm²) × Emission time (s)

[0133] Examples of light sources that emit ultraviolet light include high-pressure mercury lamps and low-pressure mercury lamps. These light sources are advantageous because they can emit ultraviolet light of a suitable wavelength stably and with low attenuation over the emission distance, and they can easily distribute the light uniformly over the entire surface.

[0134] The following is an example of the process for forming a hardened area, using an isocyanate compound as the material for forming the hardened area.

[0135] To form a cured area on the inside of the elastic component rather than on its surface, it is advantageous to apply the curable composition to the precursor of the elastic component, then remove the excess curable composition and perform a heat treatment. The heat treatment can reduce the viscosity of the curable composition present on the surface of the precursor and promote its penetration and diffusion into the precursor. The heat treatment method is not particularly limited, and examples include a method in which a sample is passed through a heating furnace and a method in which heated air is blown. Examples of heating furnaces include a radiant furnace and a forced-air furnace, and examples of devices that generate heated air include a hot air heater and a far-infrared heater.

[0136] If the heating conditions involve a high temperature and / or a long duration, the cured area becomes wider, and the area of ​​highest hardness shifts to a position farther from the surface of the precursor. It is advantageous to heat at least the tip area of ​​the precursor for 3 minutes or more at a temperature of 80 °C or higher. Even if the tip area of ​​the precursor is heated continuously at a temperature below 80 °C, the viscosity of the isocyanate compound does not decrease to a level required for diffusion on the precursor, so the diffusion rate tends to slow down. As a result, a large amount of the isocyanate compound remains on the surface of the precursor, and the hardness of the elastic component's surface tends to be highest.The atmosphere in the heating furnace is preferably set to a temperature of more than 80 °C in order to set the surface temperature of the tip part of the precursor to 80 °C or higher.

[0137] However, the temperature and duration of this heat treatment vary depending on the amount of material impregnated into the precursor to form cured areas. In particular, under conditions where the material is sufficiently impregnated into the precursor to form a cured area (e.g., at a cured area temperature of 90 °C), a cured area may form more on the inside of the elastic component and less on the surface under furnace conditions of 100 °C for 10 minutes.

[0138] Under conditions where the material is not sufficiently impregnated with the precursor to form a cured area (e.g., at a curable composition temperature of 60 °C), it is difficult to form a cured area on the inside of the elastic component under oven heating conditions of 100 °C for 10 minutes, and this area is likely to have the highest hardness. In this case, oven heating conditions of preferably 130 °C for 10 minutes or longer are suitable.

[0139] To facilitate the formation of a cured area on the inside of the elastic component rather than across the surface, it is also effective to adjust the mixing ratio of prepolymer and curing agent in the raw material composition of the elastic component. A specific mixing ratio is advantageous such that the molar ratio (α-value) of the hydroxyl group (-OH) to the isocyanate group (-NCO) is 0.40 to 1.00, and it is even more advantageous to formulate the mixture such that the molar ratio is 0.45 to 0.95.

[0140] Regarding the state of the precursor of the elastic component during the formation of the cured area, it is preferable for a larger quantity of unreacted isocyanate groups to be present on the inner surface of the precursor. Since isocyanate groups present on the surface and inner surface of the precursor react with the isocyanate compound that forms the cured area, the interior of the elastic component is more likely to have high hardness when more unreacted isocyanate groups are present on the inner surface of the precursor.

[0141] Furthermore, the amount of residual isocyanate tends to decrease gradually over time after molding. Therefore, the formation of the cured area should preferably be carried out within 6 hours of manufacturing the elastic component. The amount of residual isocyanate can be controlled by the ratio of the raw material composition of the elastic component and the time elapsed since its manufacture.

[0142] Infrared spectroscopy (IR) can be used, for example, to measure the amount of residual isocyanate on the surface. From the IR spectrum obtained by measuring the elastic component, the NCO peak of isocyanurate (near 2260 cm⁻¹) is determined. -1 up to 2270 cm -1 ) and the aromatic ring peak of isocyanate (at 1600 cm⁻¹ -1) assigned, and the ratio (A / B) of the absorption A of NCO to the absorption B of the aromatic ring is an index for the amount of residual isocyanate. To easily form a region with higher hardness in the interior than at the surface, the A / B value, which is an index for the amount of residual isocyanate, is preferably 0.1 or greater at the surface of the elastic component. The upper limit is not particularly restricted and may, for example, be 1.5 or less. Preferably, it is, for example, 0.1 to 1.5.

[0143] To form a cured area on the surface rather than on the inside of the elastic component, it is advantageous to apply the curable composition to the precursor, then remove the excess curable composition and perform air drying or low-temperature heat treatment. Regarding heating conditions, it is advantageous to heat the tip portion of the precursor to a temperature below 80 °C. [Material for forming a hardened area]

[0144] The material used to form a cured area is not particularly restricted, as long as it can cure the precursor of the elastic component or form a cured area on the surface of the elastic component. Examples include compounds with crosslinkable functional groups, such as isocyanate compounds and (meth)acrylate. The material forming the cured area can be used after dilution with a solvent or the like. The solvent used for dilution is not particularly restricted, as long as it dissolves the materials used. Examples that do so include methanol, ethanol, toluene, xylene, butyl acetate, methyl isobutyl ketone, and methyl ethyl ketone.

[0145] When (meth)acrylate is used as the material for forming the cured area, the (meth)acrylate is not particularly restricted, and examples include alkyl (meth)acrylates such as methyl (meth)acrylate and ethyl (meth)acrylate; isocyanate (meth)acrylates, which have an isocyanate group; hydroxy (meth)acrylates, which have a hydroxy group, such as 2-hydroxy-3-methacrylic propyl acrylate and hydroxyalkyl (meth)acrylate; and silicone (meth)acrylates, such as polydimethylsiloxane containing acrylic groups. Among these, at least one from the group comprising silicone (meth)acrylate and hydroxy (meth)acrylate is preferred.

[0146] If the main material (starting material) of the elastic component is a polyester urethane elastomer, considering compatibility with the elastic component and impregnation into the elastic component, it is more advantageous to use an isocyanate compound that is a starting material of the polyester urethane elastomer as the material for forming the cured area.

[0147] The isocyanate compound that forms the hardened area can be a compound that has one or more isocyanate groups in the molecule.

[0148] The isocyanate compound that has an isocyanate group in the molecule can be aliphatic monoisocyanates such as octadecyl isocyanate (ODI) and aromatic monoisocyanates such as phenyl isocyanate (PHI).

[0149] The isocyanate compound, which has two isocyanate groups in the molecule, can generally be one such as those used to manufacture polyurethane resins, and in particular the following components can be mentioned as examples: 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), 4,4'-diphenylmethane diisocyanate (MDI), m-phenylene diisocyanate (MPDI), tetramethylene diisocyanate (TMDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), ortho-toluene diisocyanate (TODI), naphthylene diisocyanate (NDI), xylylene diisocyanate (XDI), paraphenylene diisocyanate (PDI), lysine diisocyanate methyl ester (LDI), dimethyl diisocyanate (DDI) and the like.

[0150] Examples of isocyanate compounds that have three or more isocyanate groups in the molecule include 4,4',4'-triphenylmetane triisocyanate, 2,4,4'-biphenyl triisocyanate, 2,4,4'-diphenylmetane triisocyanate, polymethylene polyphenylene polyisocyanate (polymeric MDI), and the like.

[0151] Furthermore, modified products and multimers thereof can be used as isocyanate compounds with two or more isocyanate groups. Examples of modified products include carbodiimide-modified MDIs, which have two or more isocyanate groups. Additionally, blocked isocyanates can also be used, achieved by employing a blocking agent.

[0152] Among these, MDI with high crystallinity, meaning a symmetrical structure, is preferable to effectively increase the hardness of the cured area. Furthermore, MDI comprising a modified product is preferable in terms of processability, as it is liquid at room temperature. Specifically, carbodiimide-modified MDI is preferable as a modified product. <Verfahren zur Herstellung einer Reinigungsklinge> [Production of a precursor for a cleaning blade]

[0153] The method for manufacturing a cleaning blade is not particularly restricted, and any suitable method can be selected from the known methods.

[0154] Furthermore, a suitable method for manufacturing an elastic component can be selected from the known processes, such as compression molding or centrifugal molding. If the elastic component comprises polyurethane, the following method, for example, can be used.

[0155] In a cleaning blade with a cavity for forming an elastic component, a support component is arranged with an adhesive applied to a contact section with the elastic component. Simultaneously, a prepolymer formed by partial polymerization of a polyisocyanate and a polyol, a curing agent comprising a polyol, a chain extender, a catalyst, and other additives, is placed in a casting machine and mixed and stirred in a specific ratio in a mixing chamber to obtain a raw material composition of the polyurethane elastomer.

[0156] A polyol can be added to the curing agent. To ensure a uniform spacing between the crosslinking points, it is advantageous if the average (number-average) molecular weight of the polyol added to the curing agent corresponds to the average (number-average) molecular weight of the polyol used in the prepolymer. For example, the difference in the average (number-average) molecular weight between the two polyols is preferably 500 or less, 200 or less, or 100 or less.

[0157] Furthermore, the raw material composition of the polyurethane elastomer is preferably produced (formed) by a process using a prepolymer that has a molecular weight distribution that is as uniform as possible. Initially, it is advantageous to have a step in which a polyol reacts with a polyisocyanate to obtain a prepolymer. The NCO content in the prepolymer is not particularly limited and is preferably 3.00 to 15.00 wt% and even more preferably 6.00 to 10.00 wt%.

[0158] The raw material composition is injected into the mold, a cured component (elastic component) is formed on the adhesive-coated surface of the carrier component, and the mold is removed after the reaction and curing. If necessary, the elastic component can be cut to a predetermined size to ensure the dimensional accuracy of the edges of the contact area of ​​the elastic component, and thus a cleaning blade precursor can be produced (formed) in which the carrier component and the elastic component are formed in one piece.

[0159] When the elastic component is manufactured (formed) using a centrifugal forming machine, a raw material composition of the polyurethane elastomer, obtained by mixing and stirring a prepolymer formed by the partial polymerization of a polyisocyanate and a polyol, and a curing agent comprising a polyol, a chain extender, a catalyst, and other additives, is placed in a rotating drum to produce a polyurethane elastomer sheet. This polyurethane elastomer sheet is cut to a predetermined size to ensure the dimensional accuracy of the edges of the elastic component's contact area. The resulting polyurethane elastomer sheet (elastic component) can be attached to the adhesive-coated carrier component to create a precursor for a cleaning blade. [Formation of the hardened area]

[0160] The cured area can be formed using the method described above. That is, the cured area can be formed by applying a curable composition to an area where high hardness is desired and allowing it to cure. The cured area can be formed, for example, using the following method.

[0161] First, the curable compound is applied to the first and second surfaces of the free end section of the elastic component enclosed within the precursor of the cleaning blade. Next, the free end section of the elastic component is heated, for example, to a temperature of 80 °C or higher for 3 minutes or longer. This allows the cured area to form on the surface and inside of the tip section of the elastic component.

[0162] If it is necessary to cut the elastic component to create an edge on the cleaning blade that comes into contact with the target component, the cured area of ​​the elastic component can be formed before or after cutting. In the case of centrifugal forming, the cured area can be formed before joining it to the support component.

[0163] As described above, the cleaning blade can be obtained. <Prozesskartusche und elektrophotographisches Bilderzeugungsgerät>

[0164] The cleaning blade can be used after it has been installed in the process cartridge, which is removable from the electrophotographic image-generating device. In particular, for example, in a process cartridge that has an image carrier component as the target component for cleaning and a cleaning blade positioned to clean the (surface) of the image carrier component, the cleaning blade can be used as the cleaning blade according to this principle. The process cartridge contributes to the stable formation of high-quality electrophotographic images.

[0165] The electrophotographic image-generating device comprises an image carrier component, such as a light-sensitive component, and a cleaning blade arranged to clean the surface of the image carrier component. The electrophotographic image-generating device can reliably produce high-quality electrophotographic images. [Examples]

[0166] The present disclosure is described below with reference to manufacturing examples, examples, and comparative examples, but is not limited to these examples. Other reagents or industrial chemicals than those shown in the examples and comparative examples can also be used as raw materials. [Example 1] 1. Supporting component

[0167] A galvanized steel sheet with a thickness of 1.6 mm was prepared and processed to create a support component with an L-shaped cross-section, as shown in Fig. 2 with reference 3 was obtained.

[0168] Here, a single-layer urethane metal adhesive (product name: Chemlok 219, commercially available from LORD Corporation) was applied to the area of ​​the support component with which the elastic component came into contact. 2. Preparation of raw materials for the elastic component (prepolymer)

[0169] The isocyanate used was 332.0 g of 4,4'-diphenylmethane diisocyanate (product name: Millionate MT, commercially available from Tosoh Corporation) (hereinafter referred to as 4,4'-MDI).

[0170] The polyol used was a butylene adipate polyester polyol with a number-average molecular weight of 2500 (product name: NIPPOLLAN 3027, commercially available from Tosoh Corporation) (hereinafter referred to as PBA2500), weighing 668.0 g.

[0171] The materials were reacted for 3 hours at 80 °C to obtain a prepolymer with an NCO content of 9.00% by mass. (Hardening agent, hardening agent)

[0172] Trimethylolpropane (commercially available from Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as TMP) was used at a rate of 91.1 g.

[0173] N,N'-Dimethylhexanolamine (product name: Kaolizer No. 25, commercially available from Kao Corporation) (hereinafter referred to as No. 25) was used at a dose of 0.30 g.

[0174] The materials were mixed to provide a hardening agent.

[0175] A hardening agent was added to the obtained prepolymer and mixed to obtain a polyurethane elastomer composition. 3. One-piece forming of the supporting component and the elastic component

[0176] The adhesive-coated portion of the support component was positioned to protrude into the cavity of a mold for forming the cleaning blade. A polyurethane elastomer compound was injected into the mold and cured for 5 minutes at 130 °C, after which the mold was removed to obtain a component in which the elastic component (polyurethane) and the support component were formed as a single unit.

[0177] The mold used had a release agent A applied to it prior to injection of the polyurethane elastomer composition. The release agent A was a mixture comprising 5.06 g of ELEMENT14 PDMS 1000-JC (product name, commercially available from Momentive Performance Materials Japan LLC), 6.19 g of ELEMENT14 PDMS 10K-JC (product name, commercially available from Momentive Performance Materials Japan LLC), 3.75 g of SR1000 (product name, commercially available from Momentive Performance Materials Japan LLC), and 85 g of EXXSOL DSP145 / 160.

[0178] The free end face of the polyurethane elastomer of this one-piece molded component was cut accordingly to obtain a plate-shaped elastic component with a main surface (first surface) and a tip surface (second surface), which together with the main surface form an edge. The angle of the edge was set to 90 degrees, and the spacing of the elastic component in the transverse, thickness, and longitudinal directions was set to 7.5 mm, 1.8 mm, and 240 mm, respectively. Hereinafter, the precursor for the cleaning blade obtained here will be referred to as precursor A. 4. Formation of a hardened area

[0179] A carbodiimide-modified MDI (product name: Millionate MTL, commercially available from Tosoh Corporation) was prepared as a material for forming the cured area. The cured area material was heated to 80 °C, and the elastic component was immersed in the material for 20 seconds, so that the other five surfaces (the first surface, the second surface, the surface opposite the first surface, and both end surfaces in the longitudinal direction) were cured, with the exception of the surface supported by the support component (reference numeral 11 in [reference number]). Fig. 2) were immersed, and the material for forming a cured area was applied to the (surface) areas. Subsequently, the material for forming the cured area on the surface of the elastic component was wiped off using a sponge soaked in butyl acetate as a solvent.

[0180] Next, the material impregnated into the elastic component, forming the cured area, was heated in an electric oven at 40 °C for 40 minutes to further diffuse and cure it within the elastic component. This resulted in a cleaning blade 1 in which cured areas formed on five surfaces of the elastic component and on the inner surface beneath these five surfaces. Here, the cured area was formed 1 hour after the elastic component was formed (hereinafter referred to as treatment condition A). The resulting cleaning blade was evaluated according to the following procedure: <1. Measurement of the distance L of the hardened area and the maximum value DHmax of the dynamic hardness>

[0181] The dynamic hardness was measured using the following procedure. The measuring instrument used was the "Shimadzu Dynamic Ultra Micro Hardness Tester DUH-W211S" (commercially available from Shimadzu Corporation). A 115° triangular pyramid indenter was used, and the dynamic hardness was determined using the following formula. Dynamic hardness (kgf / m2):DH=α×P / D2

[0182] In the formula, a denotes a constant that depends on the shape of the indenter, P denotes a test force (mN) and D denotes a penetration depth of the indenter into a sample (penetration depth) (µm).

[0183] The measurement conditions are as follows. a: 3.8584 P: 1.0 mN Load rate: 0.03 mN / s Hold time: 5 seconds Measurement environment: Temperature 23 °C and relative humidity 55% Aging of the measurement sample: it was left for 6 hours or longer in an environment with a temperature of 23 °C and a relative humidity of 55%.

[0184] One procedure for preparing a measurement sample is as follows. If the length of the elastic component in the longitudinal direction was LE, the measurement samples were cut with a sharp blade from the centers (16 points, PL1, PL2, ..., PL1). 16 ) of 16 line segments of length LE / 16, obtained by dividing the elastic component into 16 equal parts in the longitudinal direction, with a size of 4 mm in the longitudinal direction (2 mm in both longitudinal directions from the center point), 2 mm from an edge 7 in the transverse direction and 2 mm in the thickness direction (see Fig. 4A and Fig. 4B) cut out.

[0185] The dynamic hardness of the elastic component was measured by positioning the sample so that the indenter struck the surface (the first surface and the second surface) of the test specimen perpendicularly at a position 2 mm from the end in the longitudinal direction and at a position 100 µm to 500 µm from the edge in the transverse or thickness direction. An enlarged view of Fig. Figure 4A shows a view in which the sample is arranged so that the indenter hits the second surface of the sample perpendicularly.

[0186] When the dynamic hardness was measured at measurement positions 10 µm away from the edge on a straight line bisecting the angle of the edge in a cross-section perpendicular to the longitudinal direction of the elastic component, the presence of a region where the dynamic hardness decreased from the edge towards the inside of the elastic component was measured by the following procedure.

[0187] Sixteen cut-out samples (section samples) were cut with a sharp blade at a position of 2 mm in the longitudinal direction, and the sample was positioned so that the indenter struck the cut surface perpendicularly (see Fig. 5) The measurement positions were positions on a straight line that bisects the angle of the edge and is located at intervals of 10 µm from the edge (see Fig.6) The measurement was performed sequentially at these positions, and the measurement was continued until a measurement position was reached where the amount by which the dynamic hardness decreased at two adjacent measurement positions was 0.04 or less for the first time. Here, the dynamic hardness at the measurement position closest to the edge was compared with the dynamic hardness at a measurement position closer to the inside of the elastic component than the measurement position, and the presence of a region where the dynamic hardness decreases from the edge to the inside of the elastic component was confirmed. Furthermore, the distance between the edge and a measurement position 61 located within the elastic component, where the amount by which the dynamic hardness decreased at two adjacent measurement positions was 0.04 or less for the first time, was defined as the distance L.Furthermore, the maximum value of the dynamic hardness at the measuring positions is DHmax. The dynamic hardness at each measuring position is given in . Fig. 7 is represented by the solid line. In Fig. 7 confirmed that there was an area where the dynamic hardness decreased at a position at a distance of 10 to 80 µm from the edge.

[0188] The preceding measurement was performed on 16 test specimens, and the coefficient of variation of the distance L and the coefficient of variation of the maximum value DHmax of the dynamic hardness were calculated. Here, the coefficient of variation was calculated according to the following formula (1). Coefficient of variation = Standard deviation / Average value [Method for removing the hardened area]

[0189] As described above, the area (cured area) where the dynamic hardness decreases was formed according to the dynamic hardness measurement up to a distance L from the edge of the elastic component. Before forming the cured area, i.e., to measure the physical properties of the urethane elastomer contained in the precursor, the physical properties of the polyurethane elastomer contained in the elastic component were measured at a distance L from the edge along a straight line bisecting the angle of the edge. Specifically, a sample was prepared by removing sections from the surfaces of the elastic component to a depth of 500 µm using a sharp blade. This operation was to remove the cured area, which contains the cured product of the curable composition.When this sample was subjected to the following measurement, it was possible to determine the physical properties of the polyurethane elastomer that had not yet been impregnated with the curable composition, that is, that it can be considered identical to the polyurethane elastomer comprising the precursor.

[0190] The following T2 relaxation time measurements, FT-IR analysis, and M1 and M2 measurements were performed on this sample. Here, the area obtained from the test sample by removing a region from the first surface of the elastic component to a depth of 500 µm is referred to as the surface corresponding to the first surface of the elastic component, and the area obtained by removing a region from the second surface of the elastic component to a depth of 500 µm is referred to as the surface corresponding to the second surface of the elastic component. In this case, the surface corresponding to the first surface of the elastic component and the surface corresponding to the second surface of the elastic component formed an edge A'. <2. Measurement of T2 relaxation time>

[0191] The spin-spin relaxation time (T2) was measured using the solid echo method in pulse NMR analysis.

[0192] Regarding the sample, a measurement sample was cut at the measurement positions described below and divided into small pieces measuring 1 mm × 1 mm, and 1 g of the pieces was placed in a test tube.

[0193] The pulse NMR measurement conditions are as follows. Device: JNM-MU25 (available from JEOL Ltd.) Condition: Solid-echo method Measurement environment: 50 °C Number of measurements: 128

[0194] The measurement results were separated into two components (soft segment and hard segment) using the least squares method in the software supplied with the device, and the respective spin-spin relaxation times (T2) were calculated. L and T2 S ) were received.

[0195] In the present disclosure, the obtained T2 relaxation curve was separated into two components, a hard segment and a soft segment, according to the length of the relaxation time. Specifically, the T2 relaxation curve was separated into two components, a hard segment and a soft segment, by curve fitting using the following formula, and the spin-spin relaxation time (T2) was determined. L ) of the soft segment and the spin-spin relaxation time (T2) S ) of the hard segment were calculated. M(t)=ALexp[−(tT2L)mi]+ASexp[−(tT2S)mi] M(t) macroscopic magnetization A L Intensity at t=0 of the component with long relaxation time (soft segment) T2 L T2 relaxation time of the component with a long relaxation time (soft segment) A S Intensity at t=0 of the component with short relaxation time (hard segment) T2 ST2 relaxation time of the component with a short relaxation time (hard segment) with Weibull coefficient

[0196] Measurement position: The length of edge A' was L0, the measurement was carried out at positions 1 / 8L0, 1 / 2L0 and 7 / 8L0 from an end face of edge A', and the average values ​​of these are shown in Table 1-1 and Table 1-2. <3. FT-IR analysis of the elastic component using the ATR method>

[0197] The peak intensity values ​​at 1415 cm -1 and the peak intensity at 1538 cm -1 The elastic component was measured using the ATR method with FT-IR.

[0198] The samples used were measurement samples cut out at the measurement positions described below.

[0199] The conditions for the FT-IR measurement are as follows. Device: FT / IR-4700 (available commercially from JASCO Corporation) Measurement mode: ATR method (crystal: diamond) Cumulative number of measurements: 64 Measurement position: The length of edge A' was L0, and the measurement was performed at positions 1 / 8L0, 1 / 2L0 and 7 / 8L0 from one end of edge A'.

[0200] From the obtained peak intensities, the value of the peak intensity at 1415 cm was calculated. -1 / the peak intensity at 1538 cm -1 calculated, and their arithmetic means are listed in Table 1-1 and Table 1-2. <4. Method for measuring M1 and M2>

[0201] M1 and M2 were measured using a direct sample introduction (DI) method, in which the sample was introduced directly into an ion source without prior gas chromatography (GC).

[0202] The instrument used was POLARIS Q (commercially available from Thermo Fisher Scientific), and a Direct Exposure Probe (DEP) was used.

[0203] In the test sample, it was assumed that a line segment was drawn on the surface, corresponding to the tip of the elastic component parallel to edge A' at a distance of 0.5 mm from edge A', where the length of the line segment is L' and points located 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the line segment, respectively, are P0', P1', and P2'. The polyurethane was scraped off P0', P1', and P2' using a biocutter.

[0204] 0.1 µg of the sample to be analyzed was fixed to a filament positioned at the tip of the probe at each of points P0', P1', and P2', and inserted directly into the ionization chamber. The sample was then rapidly heated from room temperature to 1000 °C at a specific rate of increase (10 °C / s), and the vaporized gas was measured using a mass spectrometer.

[0205] The total integrated intensity of all peaks in the obtained total ion current thermogram was used as the quantity M1 of all detected ions.

[0206] The integrated intensity of the peak values ​​of the extracted ion thermogram, derived from the polymeric MDI and corresponding to an m / z value range of 380.5 to 381.5, was M2, and M2 / M1 was calculated. Here, the arithmetic mean of the values ​​obtained at P0', P1', and P2' was used as the value of M2 / M1 in the present disclosure. <5. Evaluation of cleaning performance>

[0207] A cleaning blade 1 was installed in a cyan cartridge of a color laser printer (product name: HP LaserJet Enterprise Color M555dn, commercially available from Hewlett-Packard Company). This cleaning blade served as a cleaning target component for a photosensitive drum. Additionally, the toner in the developer unit of the cyan cartridge was completely replaced with a toner 1, which is described below.

[0208] Subsequently, images were produced on 13,000 sheets, corresponding to the number of printable sheets, in a low-temperature, low-humidity environment (a temperature of 15 °C and a relative humidity of 10%) (hereinafter referred to as "normal evaluation"). Under these image-producing conditions, a 10-second pause (operating pause time) was implemented after each printout of an image sheet.

[0209] Furthermore, the developing machine was replaced with a new developing machine for a black process cartridge, and images were produced on an additional 13,000 sheets, corresponding to the number of printable sheets (hereinafter referred to as the "dual production evaluation"). Additionally, the evaluation was performed while the residual toner was vacuumed out of a hole in the rear of the process cartridge at an appropriate time. The resulting images were ranked according to their performance (appearance) based on the following evaluation criteria. The evaluation results are presented in Table 2. A: Neither in the normal evaluation nor in the double production evaluation did any image defects (stripes on the image) occur that were caused by the cleaning blade. B: Image defects (streaks on the image) caused by the cleaning blade did not occur during normal evaluation, but they did occur to a small extent during double production evaluation; however, the defects were unproblematic in practical application. C: Image defects (streaks on the image) caused by the cleaning blade occurred in both normal and double production evaluations. <6. Method for the production of toner 1>

[0210] Unless otherwise stated, the term "parts" in the following refers to mass. (Step 1 for preparing aqueous medium)

[0211] 650 parts of deionized water were placed in a reaction vessel equipped with a stirrer, thermometer, and reflux tube. 14 parts of sodium phosphate dodecahydrate (commercially available from Rasa Industries, Ltd.) were added, and the mixture was maintained at 65°C for 1 hour while purged with nitrogen. Using a TK homomixer (commercially available from Tokushu Kika Kogyo Co., Ltd.), a calcium chloride-aqueous solution containing 9.2 parts calcium chloride (dihydrate) dissolved in 10 parts deionized water was added all at once while stirring at 15,000 rpm to prepare an aqueous medium containing a dispersion stabilizer. Additionally, 10% by mass of hydrochloric acid was added to the aqueous medium, and the pH was adjusted to 5.0 to obtain aqueous medium 1. (Step to prepare the polymerizable monomer composition) Styrene: 60.0 pieces CI Pigment Blue 15:3:6.5 parts

[0212] The materials were placed in an attritor (commercially available from Mitsui Miike Machinery Co., Ltd.) and additionally dispersed with 1.7 mm diameter zirconium dioxide particles at 220 rpm for 5.0 hours to prepare a pigment-dispersed solution. The following materials were added to the pigment-dispersed solution. Styrene: 20.0 pieces n-Butyl acrylate: 20.0 pieces Crosslinking agent (divinylbenzene): 0.3 parts Saturated polyester resin: 5.0 pieces (Polycondensation product of propylene oxide-modified bisphenol A (2-mol-o-adduct) and terephthalic acid (molar ratio 10:12), glass transition temperature Tg = 68 °C, weight-mean molecular weight Mw = 10000, molecular weight distribution Mw / Mn = 5.12) Fischer (with a melting point of 78 °C): 7.0 pieces

[0213] These materials were kept at 65 °C and uniformly dissolved and dispersed using a TK homomixer (commercially available from Tokushu Kika Kogyo Co., Ltd.) at 500 rpm to prepare a polymerizable monomer composition. (Granulation step)

[0214] While maintaining the temperature of aqueous medium 1 at 70 °C and the rotational speed of the TK homomixer at 15,000 rpm, the polymerizable monomer composition was added to aqueous medium 1, along with 10.0 parts of tert-butyl peroxypivalate as a polymerization initiator. Granulation was then carried out directly for 10 minutes while maintaining the rotational speed of 15,000 rpm with the stirring device. (Polymerization and distillation step)

[0215] After the granulation step, the stirrer was replaced by a propeller stirrer blade, the polymerization was carried out for 5.0 hours at 150 rpm and a temperature of 70 °C, the temperature was increased to 85 °C and heating was carried out for 2.0 hours to induce a polymerization reaction.

[0216] Subsequently, the reflux tube of the reaction vessel was replaced by a cooling tube, the slurry was heated to 100 °C, distilled for 6 hours, and the unreacted polymerizable monomers were distilled off to obtain a toner-based particle-dispersed solution. (Polymerization of the organosilicon compound)

[0217] 60.0 parts of deionized water were weighed into a reaction vessel equipped with a stirrer and a thermometer, and the pH was adjusted to 4.0 using 10% hydrochloric acid by mass. This was heated during stirring, and the temperature reached 40°C.

[0218] Then, 40.0 parts of methyltriethoxysilane, an organosilicon compound, were added, and the mixture was stirred for 2 hours or longer to perform hydrolysis. The endpoint of hydrolysis was visually verified when the oil and water no longer separated and remained in a single layer, and cooling was performed to obtain a hydrolysis solution containing the organosilicon compound.

[0219] The temperature of the resulting toner-based particle-dispersed solution was cooled to 55 °C, and then 25 parts of the organosilicon compound hydrolysis solution were added to initiate polymerization of the organosilicon compound. After the mixture was maintained unchanged for 15 minutes, the pH was adjusted to 5.5 with a 3.0 wt% sodium bicarbonate-aqueous solution. The mixture was maintained at 55 °C for 60 minutes with continuous stirring, then the pH was adjusted to 9.5 with a 3.0 wt% sodium bicarbonate-aqueous solution, and the mixture was maintained for a further 240 minutes to obtain a toner-particle-dispersed solution. (Washing and drying step)

[0220] After completion of the polymerization step, the toner particle-dispersed solution was cooled, hydrochloric acid was added, the pH was adjusted to 1.5 or lower, the mixture was stirred and allowed to stand for 1 hour, and then subjected to solid-liquid separation using a pressure filter to obtain a toner cake. This was resuspended with deionized water to create a dispersion solution, and the mixture was then subjected to solid-liquid separation using the aforementioned filter to obtain a toner cake.

[0221] The resulting toner cake was dried in a thermostat chamber at 40 °C and classified for 72 hours to obtain a toner grade 1. [Examples 2 to 9 and comparative examples 1 to 8]

[0222] Prepolymers and curing agents were prepared (formed) in the same manner as in Example 1, except that the formulation materials and their amounts were modified as shown in Table 1-1 and Table 1-2, yielding polyurethane elastomer compositions. Precursors B to M were obtained using the polyurethane elastomer composition obtained. Cleaning blades were prepared (formed) in the same manner as in Example 1, except that precursors A to M were treated under the conditions shown in Table 2, Table 3, and below, and the resulting cleaning blades were evaluated in the same manner as in Example 1. The dynamic hardness at each measurement point on the straight line bisecting the angle of the cleaning blade edge according to Example 3 is shown by the dotted line in Figure 1. Fig. 7 indicated. Fig.7 confirmed that there was an area where the dynamic hardness decreased at a position 40 to 90 µm from the edge.

[0223] The evaluation results are presented in Table 1-1, Table 1-2, Table 2, and Table 3. Furthermore, the cleaning blades obtained in Examples 2 to 9 and the comparison examples 1 to 8 exhibit the area where the dynamic hardness decreases from the edge towards the inside of the elastic component.

[0224] Details of the materials used, which differ from those in Example 1, are as follows. Polybutylene adipate polyester polyol having a number-average molecular weight of 1000 (product name: NIPPOLLAN 4009, commercially available from Tosoh Corporation) (hereinafter referred to as PBA1000); Polybutylene adipate polyester polyol having a number-average molecular weight of 2000 (product name: NIPPOLLAN 4010, commercially available from Tosoh Corporation) (hereinafter referred to as PBA2000); Polyhexylene adipate polyester polyol having a number-average molecular weight of 1000 (product name: NIPPOLLAN 164, commercially available from Tosoh Corporation) (hereinafter referred to as PHA1000); Polytetramethylene ether glycol having an average (number-average) molecular weight of 1000 (product name: PTG-1000SN, commercially available from Hodogaya Chemical Co., Ltd.) (hereinafter referred to as PTMG1000); Polymeric MDI (product name: Millionate MR-400, commercially available from Tosoh Corporation) (hereinafter referred to as pMDI); 1,4-Butanediol (commercially available from Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as 1,4-BD); POLYCAT46 (available commercially from Air Products Japan, KK) (hereinafter referred to as PC46); TEDA (triethylenediamine) (commercially available from Tosoh Corporation); K-KAT XK-627 (available commercially from Kusumoto Chemicals, Ltd.) (hereinafter referred to as K-KAT). [Table 1-1] Precursor A Precursor B Precursor C PrecursorD Precursors PrecursorF PrecursorG PrecursorH Recipe Prepolymer MDI Amount added (g) 332 332 350 348 332 332 379 371 pMDI Amount added (g) 0 0 0 0 20 0 0 0 Polyol type PBA2500 PBA2500 PBA2000 PBA1000 PBA2500 PHA2500 PTMG1000 PTMG1000 Amount added (g) 668 668 650 652 648 668 621 628 Hardener 1.4-BD Amount added (g) 0 0 0 0 0 0 0 0 TMP Amount added (g) 91,1 70,4 91,1 62,7 97,4 91,1 75,9 68,9 Polyol type - PHA1000 - - - - - PTMG1000 Amount added (g) 0 70,4 0 0,0 0 0 0 69 No. 25 Amount added (g) 0,30 0,20 0,30 0,20 0,30 0,30 0,20 0,40 PC46 Amount added (g) 0 0,06 0 0 0 0 0 0,00 TEDA Amount added (g) 0 0 0 0 0 0 0 0 K-CAT Amount added (g) 0 0 0 0 0 0 0 0 Crosslinking agent concentration mmol / g 0,62 0,46 0,62 0,44 0,65 0,62 0,53 0,45 Pulse NMR T2L us 294 320 255 273 280 297 271 294 T2S us 56,0 53,3 56,4 68,4 54,5 56,4 65,2 84,5 IR 1415cm -1 / 1538cm-1 - 0,56 0,64 0,55 0,53 0,54 0,56 0,57 0,56 Mass analysis M2 / M1 - 0,0000 0,0000 0,0000 0,0000 0,0008 0,0000 0,0000 0,0000 [Table 1-2] Precursors I Precursor J Precursor K PrecursorL PrecursorM Recipe Prepolymer MDI Amount added (g) 363 286 327 343 188 pMDI Added amount (9) 0 0 0 0 210 Polyol type PBA2000 PBA2000 PBA2500 PBA1000 PBA2500 Amount added (g) 637 714 673 657 602 Hardener 1.4-BD Added amount (9) 0 0 12,9 0 0 TMP Added amount (9) 91,1 20,4 23,7 46,1 58,0 Polyol type - - PHA1000 - PHA1000 Added amount (9) 0 0,0 167,9 0,0 328,9 No. 25 Added amount (9) 0,27 0,00 0,35 0,17 0,53 PC46 Added amount (9) 0 0 0 0 0 TEDA Added amount (9) 0 0,1 0 0 0 K-CAT Added amount (9) 0 0,2 0 0 0 Crosslinking agent concentration mmol / g 0,62 0,15 0,15 0,32 0,29 Pulse NMR T2L us 255 352 334 270 327 T2S us 42,8 33,5 49,1 90,5 52,1 IR 1415cm-1 / 1538cm-1 - 0,56 0,61 0,80 0,56 0,636 Mass analysis M2 / M1 - 0,0000 0,0000 0,0000 0,0000 0,0120 [Table 2] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 precursor A A B C D E F G H Treatment condition A B C A D F G D E Impregnation depth L Standard deviation µm 13 81 21 7 14 10 10 11 21 Average µm 57 342 81 42 75 52 41 61 91 coefficient of variation 0,23 0,24 0,26 0,17 0,19 0,19 0,24 0,18 0,23 Dynamic Hardness Peak Value Dhmax Standard deviation kgf / m 2 0,11 0,54 0,16 0,04 0,14 0,05 0,11 0,07 0,14 Average kgf / m 2 0,62 2,82 0,82 0,28 0,79 0,30 0,55 0,46 0,75 coefficient of variation 0,18 0,19 0,20 0,14 0,18 0,17 0,20 0,15 0,19 Evaluation A A B A A A B A B [Table 3] Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 Comparative example 7 Comparative example 8 precursor I J K K K K L M Treatment condition C A C A F G D E Impregnation depth L Standard deviation µm 35 32 26 35 38 24 25 25 Average µm 104 89 58 74 81 52 81 84 coefficient of variation 0,34 0,36 0,45 0,47 0,47 0,46 0,31 0,30 Dynamic Hardness Peak Value Dhmax Standard deviation kgf / m 2 0,30 0,50 0,14 0,20 0,30 0,40 0,30 0,20 Average kgf / m 2 1,10 1,20 0,33 0,48 0,50 0,72 0,91 0,61 coefficient of variation 0,27 0,42 0,43 0,42 0,60 0,56 0,33 0,33 Evaluation C C C C C C C C

[0225] Table 2 and Table 3 describe the treatment conditions B to G as follows.

[0226] Treatment condition B was identical to treatment condition A, except that the immersion time of the material to form a hardening zone was changed to 300 seconds and the time for heating in the electric oven was changed to 60 minutes.

[0227] Treatment condition C was the same as treatment condition A, except that the temperature for heating in the electric oven was changed to 80 °C.

[0228] In treatment condition D, the same material used in treatment condition A was heated to 80 °C to form a hardened area. The coating quantity was set to 20 drops or 18 mg, and the coating was applied to the vertical (second) surface of the elastic component using a dispenser while the component was moved at 100 mm / s. This one-piece molded component was then left for 10 minutes in an environment at 25 °C and 50% relative humidity, and then heated for 40 minutes in an electric oven at 80 °C to create a cleaning blade. This means the hardened area was formed only on one surface, the vertical (second) surface of the elastic component.

[0229] Treatment condition E was the same as treatment condition D, except that the temperature for heating in the electric oven was changed to 40 °C.

[0230] In treatment condition F, 100 parts of an acrylic-containing polydimethylsiloxane (UV3505, commercially available from BYK Japan) were added as a silicon-containing UV-curable material, along with 0.5 parts of 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Darocur 1173, commercially available from Ciba Specialty Chemicals) as a photoinitiator. The mixture was blended to produce a curable composition. Using the resulting curable composition, it was applied to each surface of the elastic component in the same manner as in treatment condition A. The precursor was then swollen in an electric oven at 40 °C for 1 hour. Finally, the curable composition was wiped off the surface of the elastic component using a sponge soaked in methyl ethyl ketone as a solvent.The temperature was then brought back to room temperature and UV light was applied for 5 minutes at an intensity of 140 W / cm using a UV emission device (UVC-2534 / 1MNLC3, commercially available from Ushio Inc.). 2 emitted to obtain a cleaning blade.

[0231] Under treatment conditions G, a mixture of 100 parts of a hydroxyl-containing alkyl acrylate (701A, 2-hydroxy-3-methacrylpropyl acrylate, commercially available from Shin-Nakamura Chemical Co., Ltd.) and 2 parts of phenyl(1-hydroxycyclohexyl) ketone (Irgacure 184, commercially available from BASF Japan Ltd.) as a polymerization initiator, diluted with 100 parts of cyclohexanone, was used as a curable composition. Using the obtained curable composition, it was applied to each surface of the elastic component in the same manner as in treatment condition A. Next, the precursor was expanded in an electric furnace at 25 °C for 300 seconds. Then, the curable composition was wiped off the surface of the elastic component with a sponge soaked in methyl ethyl ketone as a solvent.The temperature was then brought back to room temperature and irradiated using a UV emission device (UB031-2A / BM, commercially available from Eye Graphics Co., Ltd.) at a distance of 300 mm with a cumulative amount of light (UV light) of 100 J / m. 2 It emits ultraviolet light.

[0232] While the present disclosure has been described with reference to embodiments, it is obvious and understandable that the present disclosure is not limited to the disclosed embodiments. The scope of the following claims is to be interpreted as broadly as possible to encompass all such modifications and equivalent structures and functions.

[0233] This application claims the benefit and priority of Japanese patent application No. 2023-20665, which was filed on February 14, 2023, and which is hereby incorporated in its entirety by reference into this application. REFERENCE MARK LIST 1 Electrophotographic cleaning blade 2 Elastic component 3 Support component 4 Free end section 5 Lower surface of the elastic component 6 Vertical surface of the elastic component 7-edge 8 Cleaning target component 9 End surface of the elastic component in the longitudinal direction X Longitudinal direction Y Thickness direction Z transverse direction R Direction of rotation of the cleaning target component QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2023-20665

[0233]

Claims

[1] Electrophotographic cleaning blade comprising an elastic component and a support component that supports the elastic component, wherein the elastic component has a first surface and a second surface at a free end section of the elastic component, which together with the first surface forms an edge, in a cross-section perpendicular to a longitudinal direction of the elastic component and on a straight line that bisects an angle of the edge, when the dynamic hardness is measured at measuring positions in intervals of 10 µm from the edge, a coefficient of variation of a maximum value DHmax from dynamic hardnesses at the measurement positions in the longitudinal direction of the elastic component is not greater than 0.20, the elastic component has an area where the dynamic hardness decreases from the edge towards the inside of the elastic component, and in the area where the dynamic hardness decreases, a coefficient of variation of a distance L in the longitudinal direction of the elastic component between the edge and a measuring position located on an inside of the elastic component, when the amount by which the dynamic hardness decreases at two adjacent measuring positions is not greater than 0.04 for the first time, is not greater than 0.

28. [2] Electrophotographic cleaning blade according to claim 1, wherein the elastic component comprises a polyurethane elastomer having a hard segment and a soft segment on a side of the elastic component further inward from the edge on the straight line than the distance L, and the spin-spin relaxation time (T2 L ) of the soft segment, which is obtained by pulse NMR measurement of the polyurethane elastomer at a temperature of 50°C, is 250 to 320 µs. [3] Electrophotographic cleaning blade according to claim 1 or 2, wherein, in an FT-IR measurement of the polyurethane elastomer using a diamond as an ATR crystal, a value of a ratio of a peak intensity at 1415 cm -1 to a peak intensity at 1538 cm -1 0.50 to 0.

65. [4] Electrophotographic cleaning blade according to one of claims 1 to 3, wherein if a quantity of all detected ions, which is obtained when the polyurethane elastomer is heated to 1000 °C at a rate of rise of 10 °C / s using a direct sample feed mass spectrometer that heats and evaporates a sample in an ionization chamber and ionizes sample molecules, is M1, and if an integrated peak intensity in an extracted ion thermogram derived from polymeric MDI and corresponding to an m / z range of 380.5 to 381.5 is M2, M2 / M1 is less than 0.0010. [5] Electrophotographic cleaning blade according to one of claims 1 to 4, wherein the elastic component is obtained by selecting at least a part of at least one surface, which is from the group comprising a surface corresponding to the first surface and a surface corresponding to the second surface of the elastic component, in a precursor of the elastic component, impregnating it with a curable composition and curing the curable composition. [6] Process cartridge comprising the electrophotographic cleaning blade according to any one of claims 1 to 5. [7] Electrophotographic image generating device comprising the electrophotographic cleaning blade according to any one of claims 1 to 5.

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