Cleaning wiper blades

Abstract

To provide a cleaning wiper blade capable of exerting high wiping performance to a to-be-cleaned surface even with a small pressing force.SOLUTION: A cleaning wiper blade includes a grip portion to be gripped by a hand, and an elastic portion supported to the grip portion and configured to be pressed against a to-be-cleaned surface. The elastic portion has, at a tip side, a main surface 6 to face a to-be-cleaned member 5 and a tip surface 8 forming a tip side edge 9 with the main surface 6. When elastic moduli are measured at a pitch of 0.1 μm with respect to specific observation regions of the tip surface 8 and the main surface 6, an average value of values of the elastic moduli is between 15 MPa and 470 MPa, and the variation coefficient of the elastic moduli is 17.6% or less.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a wiper blade for cleaning the surface of a member to be cleaned. [Background technology]

[0002] BACKGROUND ART As a cleaning tool for cleaning surfaces such as glass surfaces, there is a cleaning tool having a cleaning part and a grip part that can be held by a cleaning worker (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-115471 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional wiper blades are prone to uneven wiping if pressed too lightly against the surface to be cleaned, and if pressed too strongly against the surface to be cleaned, the contact area with the member to be cleaned is prone to become irregular, and in severe cases, so-called chattering occurs, which can result in uneven wiping. In particular, on the windows of buildings or showrooms facing the road, highly adhesive dirt such as fine particles contained in car exhaust gases, dust particles from asphalt, and oil films can adhere to the glass surface and be difficult to wipe away, resulting in noticeable uneven wiping. One aspect of the present disclosure is to provide a cleaning wiper blade that is capable of exhibiting excellent wiping performance, with little occurrence of uneven wiping even without increasing the pressure applied to the surface to be cleaned. [Means for solving the problem]

[0005] The inventors have discovered that in order for a cleaning wiper blade to exhibit excellent wiping performance even with a weak pressing force, it is effective to control the elastic modulus and its coefficient of variation of a specific portion of the elastic part that contacts the member to be cleaned within a specific range.

[0006] According to one aspect of the present disclosure, a grip portion to be held by hand; an elastic portion supported by the grip portion and pressed against the surface to be cleaned; A cleaning wiper blade that cleans the surface of a member to be cleaned by bringing a part of the elastic portion into contact with the surface of the member to be cleaned, When the side of the elastic portion farthest from the grip portion is defined as the tip side of the wiper blade, The elastic portion has, at the tip end side, a main surface facing the member to be cleaned and a tip end surface forming a tip end edge together with the main surface, Assuming that a first line segment is drawn on the tip surface parallel to the tip edge at a distance of 10 μm from the tip edge, The length of the first line segment is L1, The points (1 / 8)L1, (1 / 2)L1, and (7 / 8)L1 from one end side on the first line segment are designated as P0, P1, and P2, respectively; The tip surface has a center of gravity at each of the points P0, P1, and P2, and one side is 70 μm long and parallel to the first line segment, and one side is 10 μm long and perpendicular to the first line segment. For each of three rectangular observation regions, the elastic modulus of the tip surface at 70,000 points at a pitch of 0.1 μm is measured using a scanning probe microscope, and the average value of the elastic modulus of a total of 210,000 points obtained is 15 MPa to 470 MPa. The coefficient of variation of the elastic modulus is 17.6% or less, Assuming that a second line segment is drawn on the main surface parallel to the tip-side edge and at a distance of 10 μm from the tip-side edge, The length of the second line segment is L2, The points (1 / 8)L2, (1 / 2)L2, and (7 / 8)L2 from one end side on the second line segment are designated as P3, P4, and P5, respectively; For each of three rectangular observation regions on the main surface, each of which has a center of gravity at each of the points P3, P4, and P5, and which has one side parallel to the second line segment and a length of 70 μm and one side perpendicular to the second line segment and a length of 10 μm, the elastic modulus of the main surface is measured at 70,000 points at a pitch of 0.1 μm using a scanning probe microscope, and the average value of a total of 210,000 elastic modulus values obtained is 15 MPa to 470 MPa, and The coefficient of variation of the elastic modulus is 17.6% or less. [Effects of the Invention]

[0007] According to one aspect of the present disclosure, a cleaning wiper blade can be provided that can exhibit excellent wiping performance even with a weak pressing force against a surface to be cleaned. [Brief explanation of the drawings]

[0008] [Figure 1] Figures 1(a), (b), (c), and (d) are examples of schematic diagrams of wiper blades. [Figure 2] 2(a) and 2(b) are explanatory diagrams showing the state of the wiper blade during cleaning. [Figure 3] FIG. 4 is an enlarged schematic view of a contact portion between the elastic portion of the wiper blade and the member to be cleaned. [Figure 4] Enlarged view of the area near the tip edge. [Figure 5] An enlarged view of the vicinity of the first line segment. [Figure 6] An enlarged view of the vicinity of observation area 12 with P0 as the center of gravity. [Figure 7] 7(a) and (b) are schematic diagrams of the wiper blade and the vicinity of the contact point with the member to be cleaned. [Figure 8] Schematic diagram of a test machine for evaluating the wiping performance of a wiper blade. [Figure 9] 4 is an enlarged view of the area where the elastic portion of the wiper blade contacts the glass surface. DETAILED DESCRIPTION OF THE INVENTION

[0009] In the present disclosure, unless otherwise specified, the expressions "XX to YY" or "XX to YY" representing a numerical range mean a numerical range including the lower and upper limits, which are the endpoints. When a numerical range is described in stages, the upper and lower limits of each numerical range can be combined in any way.

[0010] <Wiper blade configuration> A cleaning wiper blade (hereinafter simply referred to as a wiper blade) according to one embodiment of the present disclosure includes a grip portion 1 that is held by hand, and an elastic portion 2 that is supported by the grip portion and pressed against a surface to be cleaned, as shown in Fig. 1. The wiper blade cleans the surface of a member to be cleaned by bringing a portion of the elastic portion into contact with the surface of the member to be cleaned. FIG. 1 shows an example of a schematic diagram of a wiper blade. FIG. 1(a) shows a wiper blade having a grip portion 1 and an elastic portion 2, but as shown in FIG. 1(b), a support portion 3 that supports the elastic portion 1 may be provided between the grip portion 1 and the elastic portion 2. Alternatively, for example, as shown in FIG. 1(c), a support grip portion 4 may be provided in which the support portion and the grip portion are integrated. As shown in FIG. 1(d), the elastic portion and the grip portion may be integrated. The grip portion 1, support portion 3, and elastic portion 2 may each be detachable or integrated.

[0011] 2 is an explanatory diagram showing the cleaning process in which the elastic part 2 of the wiper blade comes into contact with and slides over the member to be cleaned 5. As shown in FIG. 2, the wiper blade can be used in either a pushing direction C from the grip part 1 toward the elastic part 2, or a pulling direction W.

[0012] Fig. 3 is an enlarged schematic view of the contact portion between the elastic portion 2 and the member to be cleaned 5. As shown in Fig. 3, when the side of the elastic portion farthest from the grip portion is defined as the tip side of the wiper blade, the elastic portion 2 has, at the tip side, a main surface 6 facing the member to be cleaned 5 and a tip surface 8 which, together with the main surface 6, forms a tip edge 9. The main surface 6 and the tip surface 8 form the tip edge 9 of the elastic portion 2 which extends along the longitudinal direction thereof.

[0013] FIG. 4 is an enlarged view of the vicinity of the distal edge 9. As shown in FIG. 4, it is assumed that a first line segment 10 is drawn on the distal end surface 8 parallel to the distal edge 9 at a distance of 10 μm from the distal edge 9. The length of the first line segment 10 is L1. FIG. 5 is an enlarged view of the vicinity of the first line segment. As shown in FIG. 5, points (1 / 8)L1, (1 / 2)L1, and (7 / 8)L1 from one end side on the first line segment 10 are designated as P0, P1, and P2, respectively. Three rectangular observation regions are set on the distal end surface 8, with their centers of gravity at points P0, P1, and P2 on the first line segment 10, and each having one side 70 μm long and parallel to the first line segment and one side 10 μm long and perpendicular to the first line segment.

[0014] Figure 6 shows an enlarged view of the vicinity of observation region 12 with P0 as the center of gravity. As with P0 in Figure 6, the elastic modulus of the tip surface was measured at 70,000 points at a pitch (interval) of 0.1 μm for each of the three observation regions, including P1 and P2, using a scanning probe microscope (hereinafter referred to as SPM). The average value of the elastic modulus values obtained for a total of 210,000 points was 15 MPa to 470 MPa, and the coefficient of variation of the elastic modulus was 17.6% or less.

[0015] As in the measurement of the tip surface described above, it is assumed that a second line segment 11 is drawn on the main surface 6 parallel to the tip edge 9 at a distance of 10 μm from the tip edge 9, as shown in Figure 4. The length of the second line segment 11 is L2. The positions (1 / 8)L2, (1 / 2)L2, and (7 / 8)L2 from one end of the second line segment 11 are designated as P3, P4, and P5, respectively. Three rectangular observation regions were set on the main surface 6, with their centers of gravity at points P3, P4, and P5 on the second line segment 11, one side being 70 μm long and parallel to the second line segment, and the other side being 10 μm long and perpendicular to the second line segment. The elastic modulus of the main surface was measured at 70,000 points in each of the three observation regions at a pitch (interval) of 0.1 μm using an SPM. The average value of the elastic modulus values obtained for a total of 210,000 points was 15 MPa to 470 MPa, and the coefficient of variation of the elastic modulus was 17.6% or less.

[0016] The behavior of the wiper blade during cleaning was observed in detail. As a result, it was confirmed that when the wiper blade was moved in the pushing direction C from the grip portion toward the elastic portion, it contacted the object to be cleaned in an area including a position about 10 μm from the leading edge 9 on the leading surface 8. Furthermore, when the wiper blade was moved in the pulling direction W, it was confirmed that it contacted the object to be cleaned in an area including a position about 10 μm from the leading edge 9 on the main surface 6. Furthermore, a wiper blade according to one aspect of the present disclosure can prevent the occurrence of unwiped areas or uneven wiping in the wiping portion of the member to be cleaned by having the average value of the elastic modulus and its coefficient of variation in the longitudinal direction of the region that can form the contact portion with the member to be cleaned satisfy predetermined regulations.

[0017] In one embodiment of the wiper blade of the present disclosure, the average value of the elastic modulus measured at a position 10 μm from the leading edge and at a predetermined position in the longitudinal direction in a region in the vicinity thereof on the leading edge and main surface that may constitute the contact portion that abuts against the member to be cleaned is 15 MPa or more and 470 MPa or less, and the coefficient of variation of the elastic modulus is 17.6% or less. The average value of the elastic modulus is preferably 32 MPa or more and 62 MPa or less. The coefficient of variation of the elastic modulus is preferably 6.0% or less. The smaller the coefficient of variation of the elastic modulus, the better. There is no particular lower limit, but it is, for example, 0.10% or more.

[0018] When the average value of the elastic modulus is within the above range, a portion of the elastic portion of the wiper blade can be brought into contact with the object to be cleaned over a narrow width along the longitudinal direction during cleaning. In other words, the contact portion can be brought close to a line contact, and the applied force is concentrated at the contact portion, so that the deposits are reliably scraped off the object to be cleaned, rather than simply wiped off or spread. As a result, extremely high wiping performance can be achieved compared to conventional wiper blades. Furthermore, a coefficient of variation in the elastic modulus of 17.6% or less means that the elastic modulus of the contact portion of the elastic portion is more uniform or more homogeneous in the longitudinal direction. Therefore, the pressing force from the wiper blade to the member to be cleaned can be applied uniformly along the longitudinal direction of the wiper blade. As a result, the cleaning surface of the wiper blade does not become undulating or disordered along the longitudinal direction during cleaning, and stable conformability and contact with the portion of the member to be cleaned are exhibited. As a result, the wiper blade according to one embodiment of the present disclosure can stably exhibit excellent wiping performance without leaving any residue or uneven wiping, even when cleaning highly adhesive dirt such as an oil film on the member to be cleaned.

[0019] The coefficient of variation of the elastic modulus is calculated by the following formula (1). Equation (1): Coefficient of variation (%) = (standard deviation / average value of elastic modulus) × 100

[0020] For example, when a wiper blade is pressed against a member to be cleaned with a load of 16.7 N / m, in the case of a conventional cleaning wiper blade, the contact angle near the contact point is approximately 25°, the nip width is 20 to 30 μm, and the maximum contact pressure is 1.5 MPa. On the other hand, in the case of the wiper blade of the present disclosure, the contact angle is measured to be approximately 55°, the nip width is 5 to 6 μm, and the contact pressure is measured to be 6.0 MPa.

[0021] Figure 7 shows a schematic diagram of the vicinity of the contact point between a wiper blade and a member to be cleaned. It has been confirmed that a conventional wiper blade makes contact with the member to be cleaned over a relatively wide area, as shown in Figure 7(a). On the other hand, a wiper blade according to one embodiment of the present disclosure makes contact with the member to be cleaned in a state close to line contact, as shown in Figure 7(b).

[0022] The material for the elastic portion 2 is not particularly limited as long as it satisfies the above-mentioned requirements for the average value of the elastic modulus and the coefficient of variation of the elastic modulus at and near a position 10 μm from the leading edge of the tip surface and the main surface, which may be the contact portion with the member to be cleaned. Specifically, for example, the elastic portion preferably contains polyurethane, which has excellent mechanical properties and is relatively easy to adjust. The polyurethane is preferably a polyurethane elastomer. Polyurethane elastomers are obtained mainly from raw materials such as polyols, chain extenders, polyisocyanates, catalysts, and other additives. The polyurethane elastomer is a block copolymer consisting of hard segments and soft segments. The hard segments are generally composed of polyisocyanates and chain extenders containing short-chain diols. Meanwhile, the soft segments are generally composed of long-chain polyols such as polyester polyols, polyether polyols, and polycarbonate polyols, and polyisocyanates.

[0023] In order to achieve the specifications regarding the average value of the elastic modulus and the coefficient of variation of the elastic modulus according to the present disclosure, for example, the properties of the block copolymer composed of the hard segment and the soft segment can be utilized. Conventional polyurethanes have relatively large hard segments formed by further aggregation of urethane bond aggregates formed by the interaction of urethane bonds. Therefore, according to the studies of the present inventors, wiper blades made using conventional polyurethanes do not satisfy at least one of the average value of elastic modulus and the coefficient of variation of elastic modulus according to the present disclosure. That is, because conventional polyurethanes have relatively large hard segments, it is difficult to achieve a coefficient of variation of 17.6% or less in the elastic modulus measured at 210,000 locations using a scanning probe microscope, as in the present disclosure. Here, in the case of polyurethanes with a small amount of hard segments themselves, further aggregation of aggregated portions of urethane bonds is suppressed, which may allow the coefficient of variation to be kept small. However, in such cases, it is difficult to achieve an average elastic modulus value of 15 MPa or more.

[0024] The elastic portion according to one embodiment of the present disclosure may be formed, for example, from polyurethane in which hard segments are finely and uniformly dispersed. Several examples of polyurethanes in which hard segments are finely and uniformly dispersed will be described below, although the constituent material of the elastic portion according to the present disclosure is not limited to these polyurethanes. By using a diisocyanate or a tri- or higher functional polyfunctional isocyanate and a diol or a tri- or higher functional polyfunctional alcohol as urethane raw materials in an appropriate concentration range, aggregation of hard segments can be suppressed, and a polyurethane in which the hard segments are finely and uniformly dispersed can be obtained.

[0025] Specifically, for example, it is preferable to use at least one of an alcohol containing a tri- or higher functional polyfunctional alcohol and an isocyanate compound containing a tri- or higher functional polyfunctional isocyanate as the urethane raw material. It is also preferable to use, as urethane raw materials, an alcohol containing at least one selected from diols and tri- or higher functional alcohols, and an isocyanate compound containing tri- or higher functional isocyanate. It is also preferable to use, as urethane raw materials, an alcohol containing a tri- or higher functional polyfunctional alcohol and an isocyanate compound containing a diisocyanate and a tri- or higher functional polyfunctional isocyanate. In particular, it is preferable to use a tri- or higher functional polyfunctional isocyanate and a tri- or higher functional polyfunctional alcohol as the urethane raw material.

[0026] Polyurethanes obtained as reaction products of tri- or higher functional isocyanates and tri- or higher functional alcohols have steric hindrance that suppresses molecular orientation and more reliably suppresses aggregation of hard segments, making them suitable for achieving the elastic modulus and coefficient of variation of the present disclosure. Furthermore, when the soft segment portion has, for example, a linear alkylene structure, the soft segments stack together, increasing crystallinity. As a result, the hard segments also become difficult to disperse. Therefore, introducing an alkylene structure with a side chain into the soft segment portion is also effective in suppressing the aggregation of the hard segments. Specifically, for example, introducing a partial structure such as that shown in the following structural formulas (i) to (iv) into the soft segment portion between two urethane bonds is effective in miniaturizing the hard segments. -CH2-CH(CH3)-CH2-CH2-O- (i) -CH2-CH2-CH(CH3)-CH2-O- (ii) -CH2-CH(CH3)-O- (iii) -CH(CH3)-CH2-O- (iv)

[0027] The structures of structural formulas (i) and (ii) are structures that are generated by ring-opening polymerization of 3-methyltetrahydrofuran, and are substantially the same. The structures of structural formulas (iii) and (iv) are structures that are generated by ring-opening polymerization of 1,2-propylene oxide, and are substantially the same. Urethane resins having these structures between two adjacent urethane bonds can be obtained by reacting polyether polyols or polyester polyols having these structures with isocyanates. Here, as the urethane raw material, bifunctional alkylene ethers are used. When using an alcohol (diol) and a bifunctional isocyanate (diisocyanate), it is usually difficult to finely disperse the hard segment. However, by introducing the above partial structure into the soft segment, it is possible to finely disperse the hard segment even when a diol and a diisocyanate are used as urethane raw materials. As a result, a polyurethane that provides a wiper blade that satisfies the parameters of the present disclosure can be obtained.

[0028] In addition to introducing side chains into the soft segments, another method for suppressing crystallization due to stacking of soft segments and preventing aggregation of hard segments is to use two or more alcohols with different carbon numbers in the linear chain portion as the urethane raw material. Polyurethanes obtained using two or more alcohols with different carbon numbers in the linear chain portion can suppress crystallization due to stacking of soft segments, even if the soft segments have a linear alkylene structure, due to the different carbon numbers. Furthermore, the different carbon numbers in the soft segments suppress aggregation of urethane bonds, thereby preventing aggregation of hard segments. Therefore, even when diols and diisocyanates having a linear alkylene structure in their molecules are used as urethane raw materials, using multiple diols with different carbon numbers in the linear alkylene structure as the diols can achieve finer hard segments. As a result, polyurethanes that provide wiper blades that satisfy the parameters described herein can be obtained. An example of multiple diols is the combined use of polybutylene adipate polyester polyol and polyhexylene adipate polyester polyol.

[0029] Examples of the alcohol include the following: Polyester polyols such as polyethylene adipate polyester polyol, polybutylene adipate polyester polyol, polyhexylene adipate polyester polyol, (polyethylene / polypropylene) adipate polyester polyol, (polyethylene / polybutylene) adipate polyester polyol, and (polyethylene / polyneopentylene) adipate polyester polyol; polycaprolactone-based polyols obtained by ring-opening polymerization of caprolactone; polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol; and polycarbonate diols. These can be used alone or in combination of two or more.

[0030] As mentioned above, it is preferable to use two or more polyols with different numbers of carbon atoms in the linear portion (alkylene chain) as the alcohol, because this suppresses crystallization of the soft segment and allows for the production of a urethane in which aggregation of the hard segment is suppressed. In this case, it is preferable to use at least two selected from the group consisting of polyester polyols such as polyethylene adipate polyester polyol, polybutylene adipate polyester polyol, polyhexylene adipate polyester polyol, (polyethylene / polypropylene) adipate polyester polyol, (polyethylene / polybutylene) adipate polyester polyol, and (polyethylene / polyneopentylene) adipate polyester polyol.

[0031] As the chain extender, diols capable of extending the polyurethane elastomer chain and polyfunctional alcohols having three or more functional groups can also be used. Examples of diols include the following: 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) ), triethylene glycol. These may be used alone or in combination of two or more.

[0032] Examples of trifunctional or higher polyfunctional alcohols include trimethylolpropane (TMP), glycerin, pentaerythritol, and sorbitol, which can be used alone or in combination of two or more.

[0033] One method for improving the elastic modulus of polyurethane elastomers is to introduce a crosslinked structure. A preferred method for introducing a crosslinked structure is to use a trifunctional or higher polyfunctional alcohol as the chain extender. Furthermore, the introduction of a branched structure into polyurethane using a trifunctional or higher polyfunctional alcohol can suppress the crystallization of polyurethane and further suppress the aggregation of hard segments. Here, a trifunctional alcohol is preferably used as the polyfunctional alcohol in order to suppress an excessive increase in hardness due to an excessive degree of crosslinking of the polyurethane. Among these, triols, which have a methylene skeleton next to a hydroxyl group and can form a flexible crosslinked structure in terms of molecular structure, are preferred because they have an even greater effect of suppressing the crystallinity of hard segments. Examples of such triols include trimethylolpropane (TMP) and glycerin.

[0034] Examples of the isocyanate compound include the following: 4,4'-Diphenylmethane Diisocyanate (4,4'-MDI), Polymeric MDI, 2,4-Tolylene Diisocyanate (2,4-TDI), 2,6-Tolylene Diisocyanate (2,6-TDI), Xylene Diisocyanate (XDI), 1,5-Naphthylene Diisocyanate (1,5-NDI), p-Phenylene Diisocyanate (PPDI), Hexamethylene Diisocyanate (HDI), Isophorone Diisocyanate (IPDI), 4,4'-Dicyclohexylmethane Diisocyanate (Hydrogenated MDI), Tetramethylxylene Diisocyanate (TMXDI), Carbodiimide-Modified MDI, Triphenylmethane-4,4',4''-Triisocyanate (TTI), Tris(phenylisocyanate)thiophosphate (TPTI).

[0035] Among these, 4,4'-MDI, in which two isocyanate groups have equal reactivity, is preferred from the viewpoint of achieving high mechanical properties. It is also preferable to use a tri- or higher-functional polyfunctional isocyanate in combination. The use of a tri- or higher-functional polyfunctional isocyanate allows for the introduction of a branched structure into the polyurethane, which is effective in further suppressing aggregation of hard segments. Furthermore, a denser crosslinked structure can be introduced into the polyurethane, which can more stably contact the elastic portion with the member to be cleaned. As a result, incomplete wiping and uneven wiping of the member to be cleaned can be more effectively suppressed.

[0036] The trifunctional or higher polyfunctional isocyanate may be at least one selected from the group consisting of triphenylmethane-4,4',4''-triisocyanate (TTI), tris(phenylisocyanate)thiophosphate (TPTI), and polymeric MDI. Among these, tris(phenylisocyanate)thiophosphate (TPTI) and polymeric MDI are more preferably used. These isocyanates have methylene groups or ether groups between multiple NCO groups, allowing the distance between multiple urethane bonds to be appropriately maintained. This is therefore advantageous in suppressing aggregation of hard segments.

[0037] Here, polymeric MDI is represented by the following chemical formula (1) and chemical formula (1)'. In chemical formula (1)', n is preferably 1 or more and 4 or less. Furthermore, chemical formula (1) is the case where n is 1 in chemical formula (1)'.

[0038] [ka]

[0039] When the elastic segment according to the present disclosure includes a polyurethane that is a cured product of a composition that includes an isocyanate compound including a diisocyanate and a tri- or higher functional isocyanate, and an alcohol including a tri- or higher functional alcohol, the elastic segment preferably has the following physical properties. That is, assume that a line segment is drawn on the tip surface and main surface of the elastic segment, parallel to the tip edge and 0.5 mm away from the tip edge. The length of the line segment is L', and the points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the line segment are designated P0', P1', and P2', respectively. The sample sampled at P0', P1', and P2' on the tip surface and the main surface is heated and vaporized in an ionization chamber, and heated to 1,000°C at a heating rate of 10°C / s using a direct sample introduction mass spectrometer that ionizes the sample molecules. The resulting detected amount of all ions is designated M1, and the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values derived from the trifunctional or higher polyfunctional isocyanate is designated M2. In this case, M2 / M1 at the tip surface and / or the main surface is preferably 0.0010 to 0.0150, and more preferably 0.0030 to 0.0150.

[0040] Furthermore, when the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values derived from the diisocyanate is M3, M3 / M1 on the tip surface and / or main surface is preferably 0.0200 to 0.1100, and more preferably 0.0380 to 0.0760.

[0041] By ensuring that M2 / M1 and M3 / M1 are within the above ranges, the polyurethane contains an appropriate amount of a structure derived from a trifunctional or higher functional isocyanate, which has low crystallinity. This results in suppressed aggregation of hard segments and more finely and uniformly dispersed hard segments. Furthermore, excessive development of crosslinked structures in the polyurethane is suppressed, making it easier to adjust the average elastic modulus to 15 MPa or more and within the range of 470 MPa.

[0042] Furthermore, it is preferable that M2 / M3 is 0.0130 or more and 0.3000 or less. M2 / M3 is a parameter that represents the ratio of the structural portion derived from diisocyanate to the structural portion derived from trifunctional or higher polyfunctional isocyanate in the isocyanate-derived structure of the polyurethane. By setting M2 / M3 within the above range, an excessive increase in the elastic modulus of the polyurethane can be suppressed, and aggregation of hard segments in the polyester can be further suppressed.

[0043] Here, the polyurethane according to one embodiment of the present disclosure is a polyurethane containing a trifunctional or higher polyfunctional isocyanate. In the case of a polyurethane produced using polymeric MDI represented by the above chemical formula (1)' as one of its raw materials, M2 may be the sum of the integrated intensities of peaks in the extracted ion thermogram obtained by the above mass spectrometry, which correspond to the m / z value range of 380.5 to 381.5 resulting from n=1 in the structure represented by chemical formula (1)', the m / z value range of 511.5 to 512.5 resulting from n=2, the m / z value range of 642.5 to 643.5 resulting from n=3, and the m / z value range of 773.5 to 774.5 resulting from n=4.

[0044] Furthermore, when the polyurethane according to one embodiment of the present disclosure is a polyurethane produced using 4,4'-MDI represented by the following chemical formula (2) as a bifunctional isocyanate (diisocyanate) as one of the raw materials, M3 may be defined as the integrated intensity of a peak corresponding to an m / z value in the range of 249.5 to 250.5 derived from the structure represented by chemical formula (2) in the extracted ion thermogram obtained by the above-described mass spectrometry. [ka]

[0045] Furthermore, when the elastic portion of the wiper blade according to one embodiment of the present disclosure contains polyurethane, which is a reaction product of a raw material composition containing an alcohol, including a trifunctional or higher polyfunctional alcohol, the elastic portion preferably has the following physical properties. Specifically, assuming that a line segment is drawn on each of the leading edge of the elastic portion, parallel to the leading edge and 0.5 mm from the leading edge, the length of the line segment is L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the line segment are designated P0', P1', and P2', respectively. Samples taken at P0', P1', and P2' on the leading edge and the main surface are measured by pyrolysis GC / MS (gas chromatography and mass spectrometry). In this case, the concentration of the tri- or higher functional alcohol in the polyurethane at the tip surface and the main surface is preferably 0.04 mmol / g to 0.39 mmol / g, more preferably 0.14 mmol / g to 0.39 mmol / g, and even more preferably 0.22 mmol / g to 0.39 mmol / g. When the concentration of the tri- or higher functional alcohol is 0.04 mmol / g or higher, aggregation of hard segments can be more reliably suppressed. Furthermore, when the concentration of the tri- or higher functional alcohol is 0.39 mmol / g or lower, excessive development of crosslinked structures in the polyurethane can be suppressed, preventing the elastic modulus from becoming too high. Therefore, the elastic portion having the above physical properties can more easily satisfy the above-mentioned requirements regarding the average elastic modulus value (15 to 470 MPa) and the coefficient of variation of the elastic modulus (17.6% or less). The concentration of the tri- or higher functional alcohol in the polyurethane is calculated by the following formula (2).

[0046] Equation (2): Concentration of trifunctional or higher polyfunctional alcohol (mmol / g) = [Amount of tri- or higher functional alcohol (g) / Molecular weight of tri- or higher functional alcohol x 1000] / [Mass of polyurethane (g)]

[0047] When the elastic portion of the wiper blade according to the present disclosure contains polyurethane, the raw material composition of the polyurethane may contain a catalyst for promoting the reaction of an isocyanate compound and an alcohol. Examples of such catalysts include tertiary amine catalysts. Specific examples include the following: dimethylethanolamine, N,N,N'-trimethylisothiazolinone ... Amino alcohols such as N,N'-dimethylhexanolamine, trialkylamines such as triethylamine, tetraalkyldiamines such as N,N,N',N'-tetramethyl-1,3-butanediamine, triethylenediamine, piperazine compounds, triazine compounds. Also usable are organic acid salts of metals such as potassium acetate and potassium alkali octylate. Furthermore, metal catalysts that are usually used in urethanization, such as dibutyltin dilaurate, can also be used. These can be used alone or in combination of two or more.

[0048] The raw materials constituting the elastic portion of the wiper blade may contain additives such as pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers, and light stabilizers, as needed, within a range that does not affect the elastic modulus and its coefficient of variation.

[0049] <Surface treatment> The elastic portion of the wiper blade may be surface-treated. Preferred surface treatment methods in the present disclosure include, for example, (i) a method including a step of irradiating an object to be treated with ultraviolet light, and (ii) a method including a step of applying a material for forming a hardened region to the object to be treated, impregnating the object with the material, and hardening the material for forming the hardened region.

[0050] (i) Surface treatment method including ultraviolet irradiation step The conditions for irradiating the workpiece (wiper blade) with ultraviolet light are not particularly limited. The ultraviolet light may have a wavelength of 400 nm or less, but preferably 200 nm or more. A wavelength of 200 nm or more can effectively increase the elastic modulus. The wavelength of the maximum emission peak of the light emitted by the light source is preferably 200 nm or more and 400 nm or less. It is particularly preferable that the wavelength of the maximum emission peak be near 254 nm, for example, in the range of 254±1 nm. This is because ultraviolet light in the above wavelength range or at the above wavelength can efficiently generate active oxygen that modifies the surface of the elastic portion of the wiper blade. When there are multiple ultraviolet light emission peaks, it is preferable that one of them be near 254 nm.

[0051] The intensity of light emitted from the light source is not particularly limited, and values measured using a spectroradiometer (product name: USR-40V / D, manufactured by Ushio Inc.), an ultraviolet integrating actinometer (product name: UIT-150-A, UVD-S254, VUV-S172, VUV-S365, manufactured by Ushio Inc.), or the like can be used. The cumulative amount of ultraviolet light irradiated onto the elastic portion of the wiper blade in the surface treatment step may be appropriately selected depending on the desired effect of the surface treatment. This can be determined by adjusting the irradiation time of light from the light source, the output of the light source, the distance from the light source, etc. For example, 10,000 mJ / cm 2 It is sufficient to determine the amount of light so as to obtain the desired cumulative amount of light.

[0052] The cumulative amount of ultraviolet light irradiated onto the elastic portion of the wiper blade can be calculated by the following method. UV cumulative light intensity (mJ / cm 2 ) = UV intensity (mW / cm 2 ) x irradiation time (sec)

[0053] As a light source that emits ultraviolet light, for example, a high-pressure mercury lamp or a low-pressure mercury lamp can be suitably used. These light sources are preferred because they can stably emit ultraviolet light of a suitable wavelength that is little attenuated over the irradiation distance and can uniformly irradiate the entire surface.

[0054] (ii) A surface treatment method including a step of applying a material for forming a hardened region to a treatment object, impregnating the material, and hardening the material. The formation of the hardened region on the tip end surface and main surface of the elastic part of the wiper blade as the processing object is carried out, for example, by applying a material for forming the hardened region to the tip end surface and main surface, and then applying the material to the tip end surface and main surface. The material is impregnated to a certain extent in the depth direction from each surface, and then the impregnated material is cured, which effectively increases the elastic modulus measured at the tip surface and the main surface.

[0055] The material for forming the hardened region may be diluted with a diluent solvent as needed and applied by known means such as dipping, spraying, using a dispenser, brushing, roller application, etc. After application of the material for forming the hardened region, further treatment such as heat treatment may be carried out. The material for forming the hardened region may be impregnated into the polyurethane contained in the elastic member. Since impregnation is facilitated by using a high-concentration, low-viscosity material for forming the hardened region, the material may be heated and impregnated without dilution. The degree of hardening may be adjusted by the temperature of the material for forming the hardened region, the impregnation or immersion time, the temperature and time of heat treatment after impregnation or immersion, and the subsequent leaving time.

[0056] The temperature of the material for forming the cured region should be about 60°C to 90°C. The impregnation or immersion time is not necessarily limited, but is preferably about 10 to 180 seconds. After applying the material for forming the cured region to the cured region, a heat treatment may be performed. This heat treatment reduces the viscosity of the material for forming the cured region present on the surface of the polyurethane, facilitating its penetration and diffusion into the polyurethane.

[0057] The heating method includes, but is not limited to, passing the material through a heating furnace, blowing heated air onto the material, etc. For example, the heating furnace may be a radiation heating furnace or a circulating air heating furnace, and the device for generating heated air may be a hot air blower or a far-infrared heater. By setting the heating conditions to a high temperature and / or a long time, the hardened region becomes wider and the elasticity becomes higher. As for the heating conditions, it is preferable that the surface temperature of the treated surface is, for example, 90°C to 110°C. Furthermore, it is preferable that the heating time is, for example, 10 minutes to 60 minutes.

[0058] Furthermore, the amount of residual isocyanate during polyurethane molding tends to gradually decrease over time after molding. Therefore, the formation of the cured region should be carried out promptly after polyurethane molding, but is not particularly limited. For example, it is recommended to carry out the formation within 3 hours. The amount of residual isocyanate can also be adjusted by the mixing ratio of the composition used during polyurethane formation.

[0059] When the elastic portion of the wiper blade is made of polyurethane, the material for forming the hardened region is not particularly limited as long as it can be hardened in the polyurethane to form a hardened region or on the surface of the polyurethane. Examples of such materials include isocyanate compounds and acrylic resins. The material for forming the hardened region may be diluted with a solvent or the like. The solvent used for dilution is not particularly limited as long as it dissolves the material used, and examples thereof include toluene, xylene, butyl acetate, methyl isobutyl ketone, and methyl ethyl ketone.

[0060] When an isocyanate compound is used as a material for forming the hardened region, an isocyanate compound having one or more isocyanate groups in the molecule can be preferably used. As the isocyanate compound having one isocyanate group in the molecule, an aliphatic monoisocyanate such as octadecyl isocyanate (ODI) or an aromatic monoisocyanate such as phenyl isocyanate (PHI) can be used. As the isocyanate compound having two isocyanate groups in the molecule, those generally used in the production of polyurethane resins can be used. Specific examples include the following: 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), 4,4'-diphenylmethane diisocyanate ( Examples of isocyanate compounds having three or more isocyanate groups in the molecule include: 4,4',4"-triphenylmethane triisocyanate, 2,4,4'-biphenyl triisocyanate, and 2,4,4'-diphenylmethane triisocyanate. In addition, modified derivatives and polymers of isocyanate compounds having two or more isocyanate groups can also be used. To efficiently increase the hardness of the cured region, MDI with high crystallinity, i.e., MDI with a symmetric structure, is preferred. Furthermore, MDI containing modified compounds is liquid at room temperature, making it easy to work with.

[0061] <Method for manufacturing elastic part of wiper blade> The method for manufacturing the elastic portion of the wiper blade is not particularly limited and can be selected from known methods. For example, a method can be used in which a polyurethane raw material composition is injected into a cavity in a mold for the elastic portion of the wiper blade, heated to harden, and then demolded to obtain a molded product. The molded product may be used as is as a wiper blade. Alternatively, the molded product may be appropriately shaped, such as by cutting, before being used as a wiper blade. In this case, cutting the elastic portion and shaping the tip surface and main surface is preferable because it can increase the smoothness of the tip edge. Another molding method involves producing a pair of tandem-shaped molded bodies formed with the tip surfaces of the elastic portions abutting against each other and cutting them longitudinally to produce a wiper blade.

[0062] <Configuration of cleaning wiper blade> The wiper blade includes a grip portion 1 and an elastic portion 2 supported by the grip portion 1 and pressed against the surface to be cleaned. A support portion 3 may be located between the elastic portion 2 and the grip portion 1 and support the elastic portion 2. The grip portion 1 is a portion that can be held by the cleaning subject, such as a human or robot hand. As shown in FIG. 1(a) or 1(b), the grip portion 1 is connected to the elastic portion directly or via the support portion 3. The grip portion 1 may be detachable from or integrated with the elastic portion 2 and the support portion 3. The grip portion 1 extends in a direction intersecting the extension direction of the elastic portion 2. The shape of the grip portion 1 is not particularly limited as long as it can be grasped or held by the cleaning subject. A jig may be attached to the grip portion to assist in cleaning. For example, a jig that extends the grip portion for cleaning high places may be used. The material of the grip portion 1 is not particularly limited and may be made of resin or metal.

[0063] As shown in FIG. 1(b), the support portion 3 is located between the elastic portion 2 and the grip portion 1 and supports the elastic portion 2. The wiper blade may not have the support portion 3, as shown in FIG. 1(a), and the elastic portion 2 may be directly connected to the grip portion 1. However, it is preferable to have a support portion to stabilize the elastic portion and bring it into contact with the object to be cleaned. The support portion 3 is connected to the elastic portion 2 in a direction perpendicular to the direction in which the elastic portion 2 extends. The elastic portion 2 may be detachable from the support portion 3 or may be integrated with the support portion 3. The shape of the support portion 3 is not limited as long as it can support the elastic portion 2. For example, the support portion 3 may be shaped to sandwich a portion of the elastic portion 2. The material of the support portion 3 is not particularly limited, and it may be made of resin or metal.

[0064] <How to use wiper blades> This section explains how to use wiper blades. The cleaning work is carried out by holding the grip part 1 or the support grip part 4, pressing the elastic part 2 against the surface of the object to be cleaned, and moving the wiper blade in a direction intersecting the direction in which the elastic part 2 extends to remove dirt. An explanatory diagram of the cleaning process is shown below. The direction in which the wiper blade is moved is, for example, a direction intersecting the direction in which the elastic portion 2 extends, and the wiper blade can be moved in the pushing direction C shown in FIG. 2(a) and the pulling direction W shown in FIG. 2(b). Alternatively, the stains may be wetted in advance with a liquid detergent or water, and then removed together with the liquid detergent or water.

[0065] <Wiper blade shape> In the wiper blade, there are no limitations on the shapes and attachment methods of the elastic portion 2, the support portion 3, and the grip portion 1 or the support grip portion 4. Furthermore, there are no limitations on the attachment method of the support portion 3 to the elastic portion 2, or the attachment method of the grip portion 1 or the support grip portion 4 to the support portion 3. [Example]

[0066] The present disclosure will be described below with reference to Production Examples, Examples, and Comparative Examples, but the present disclosure is not limited to these Examples. Reagents or industrial chemicals were used as raw materials other than those indicated in the Examples and Comparative Examples. Note that "parts" in the Examples and Comparative Examples are all by mass unless otherwise specified.

[0067] Example 1 <Preparation of raw material for elastic part> The materials in Table 1 below were mixed and reacted at a temperature of 80° C. for 3 hours to prepare a prepolymer having an NCO content of 10.0% by mass. [Table 1]

[0068] The materials shown in Table 2 below were mixed to prepare a curing agent. [Table 2]

[0069] The prepolymer and the curing agent were mixed to prepare a polyurethane raw material composition. This raw material composition was poured into a mold for molding the elastic part of a wiper blade and cured at 130°C for 2 minutes. The mold was then demolded to obtain a polyurethane molded body. Prior to molding, release agent A was applied to the inside of the mold. Release agent A was a mixture of the materials shown in Table 3. [Table 3]

[0070] The tip end of this polyurethane molded article was cut to produce an elastic part having a main surface and a tip surface that, together with the main surface, constitutes a tip edge. The lengths in the thickness direction, short side direction, and longitudinal direction were 1.8 mm, 20 mm, and 300 mm, respectively. The obtained elastic part was subjected to the following evaluations.

[0071] [Evaluation 1: Measurement of polyfunctional alcohol species and concentration] Polyfunctional alcohols were detected by pyrolysis GC / MS (gas chromatography and mass spectrometry) under the following measurement conditions: Sampling position: Assuming that a line segment is drawn parallel to the tip edge on the tip surface and main surface of the elastic part, with a distance of 0.5 mm from the tip edge, the length of the line segment is L', and the points 1 / 8L', 1 / 2L', and 7 / 8L' from one end of the line segment are P0', P1', and P2', respectively. The samples were measured by the following method. For sampling, polyurethane or other materials were cut out with a biocutter. Device: Thermal decomposition equipment: Product name: EGA / PY-3030D, manufactured by Frontier Labs, Gas chromatography equipment: TRACE1310 Gas Chromatograph, manufactured by Thermo Fisher Scientific, Mass spectrometer: Product name: ISQLT, manufactured by Thermo Fisher Scientific ·Thermal decomposition temperature: 500℃ GC column: 0.25mm inner diameter x 30m stainless steel capillary column Stationary phase: 5% phenylpolydimethylsiloxane Heating conditions: Hold at 50°C for 3 minutes, then heat to 300°C at 8°C / min. ·MS conditions: Mass number range m / z10~650 Scan speed: 1 second / scan

[0072] The polyfunctional alcohol species were characterized by GC / MS. A calibration curve was created by GC analysis of known concentrations of the characterized polyfunctional alcohol species, and quantification was performed from the GC peak area ratio. The arithmetic mean values of the values obtained from the samples of P0', P1', and P2' on the tip surface and the main surface were used as the polyfunctional alcohol concentrations on the tip surface and the main surface, respectively.

[0073] [Evaluation 2: Measurement of M1 to M3] Measurements of M1 to M3 were carried out using the direct sample introduction method (DI method), in which the sample was introduced directly into the ion source without passing through a gas chromatograph (GC). The instrument used was an ion trap GC / MS (trade name: POLARIS Q, manufactured by Thermo Fisher Scientific), and the direct introduction probe used was a Direct Exposure Probe (DEP). Assuming that a line segment is drawn on the tip surface and main surface of the elastic part, parallel to the tip edge and 0.5 mm away from the tip edge, the length of the line segment is L', and the points 1 / 8L', 1 / 2L', and 7 / 8L' from one end on the line segment are designated as P0', P1', and P2', respectively. The samples sampled at P0', P1' and P2' of the tip surface and the main surface were measured by the following method: For sampling, a member such as polyurethane was cut out with a biocutter. Approximately 0.1 μg of the sample sampled at each of the P0′, P1′, and P2′ points on the tip and main surface was fixed to a filament at the tip of the probe and directly inserted into the ionization chamber. The sample was then rapidly heated from room temperature to 1000°C at a constant heating rate (approximately 10°C / s), and the vaporized gas was detected by a mass spectrometer.

[0074] The detected amount M1 of all ions is the sum of the integrated intensities of all peaks in the obtained total ion current thermogram, When the sum of the integrated intensities of the peaks in the extracted ion thermogram of the m / z values derived from the trifunctional or higher polyfunctional isocyanate was defined as M2, (M2 / M1) was calculated using the values of M1 and M2. Furthermore, when the sum of the integrated intensities of the peaks in the extracted ion thermogram of the m / z values derived from the diisocyanate was defined as M3, (M3 / M1) was calculated using the values of M1 and M3. The arithmetic mean values of the values obtained from each sample of P0', P1', and P2' on the tip surface and the main surface, respectively, were defined as the values of (M2 / M1) and (M3 / M1) on the tip surface and the main surface, respectively.

[0075] Here, in this example, TTI used as the trifunctional or higher polyfunctional isocyanate has a structure represented by the following chemical formula (3). In the thermogram, a peak derived from a cationized product of TTI was detected, with its top at m / z 366.5 to 367.5. Therefore, in this example, the integrated intensity of this peak was designated as M2.

[0076] [ka]

[0077] In other examples described later, for an elastic portion made of polyurethane synthesized using polymeric MDI as a tri- or higher functional isocyanate, peaks derived from cationized polymeric MDI were detected in the extracted ion thermogram obtained in this evaluation, with peaks having peak tops at m / z values in the range of 380.5 to 381.5 indicating n = 1 in the structure represented by chemical formula (1)', m / z values in the range of 511.5 to 512.5 indicating n = 2, m / z values in the range of 642.5 to 643.5 indicating n = 3, and m / z values in the range of 773.5 to 774.5 indicating n = 4. Therefore, in these examples, the sum of the integrated intensities of these peaks was defined as M2.

[0078] Similarly, in the examples described below, tris(phenylisocyanate)thiophosphate (TPTI) used as a trifunctional or higher polyfunctional isocyanate has a structure represented by chemical formula (4). In the extracted ion thermogram obtained in this evaluation, a peak derived from the cationized product of TPTI was detected, with a peak top at m / z 464.5 to 465.5. Therefore, in these examples, the integrated intensity of this peak was designated M2.

[0079] [ka]

[0080] On the other hand, in the extracted ion thermogram obtained in this evaluation, a peak derived from the cationized product of 4,4'-MDI represented by the above chemical formula (2) was detected, which has a peak top at m / z 249.5 to 250.5. Therefore, the integrated intensity of this peak was determined as M3.

[0081] [Evaluation 3: Measurement of elastic modulus] The elastic modulus was measured by SPM using a scanning probe microscope (SPM) (trade name: MFP-3D-Origin; manufactured by Oxford Instruments) using the following method. First, samples were prepared as follows. Assuming that a first line segment of length L was drawn on the distal end surface of the elastic section, parallel to the distal edge and 10 μm away from the distal edge, three 2 mm square measurement samples were cut out, each with one side parallel to the first line segment, with the centroids at points P0, P1, and P2, respectively, at 1 / 8L, 1 / 2L, and 7 / 8L from one end of the first line segment. Next, using a cryomicrotome (UC-6 (product name), manufactured by Leica Microsystems), a 100 μm square, 1 μm thick polyurethane slice was cut out from each measurement sample at -50°C, with the centroids at P0, P1, and P2, and with one side parallel to the first line segment. Three measurement samples were thus prepared. Each of the obtained measurement samples was placed on a smooth silicon wafer and left at room temperature of 25°C and humidity of 50% for 24 hours.

[0082] Next, the silicon wafer with the measurement sample mounted on it was placed on the SPM stage and observed with the SPM. The spring constant and proportionality constant of the silicon cantilever (product name: OMCL-AC160, manufactured by Olympus, tip curvature radius: 8 nm) were previously confirmed to be as follows using the thermal noise method installed in this SPM device: spring constant: 30.22 nN / nm, proportionality constant: 82.59 nm / V. The cantilever was also tuned in advance to determine its resonant frequency (285 kHz (first order) and 1.60 MHz (higher order)). The SPM measurement mode was AM-FM mode, the cantilever free amplitude was 3 V (primary) and 25 mV (higher order), and the set point amplitude was 2 V (primary). A phase image of each measurement sample was obtained by scanning a 70 μm × 70 μm square field of view at a scan speed of 1 Hz with 256 vertical and 256 horizontal scan points. The field of view was selected so that P0, P1, and P2 of each measurement sample were located in the center of the field of view and one side was parallel to the first line segment.

[0083] From the obtained phase image, the locations on the measurement sample where the elastic modulus was to be measured by force curve measurement were specified. Specifically, as shown in Figures 5 and 6, in the 70 μm × 70 μm phase image, the measurement locations were specified as 70,000 positions corresponding to 70,000 points at a pitch (interval) of 0.1 μm in a rectangular region with one side 70 μm long parallel to the first line segment and one side 10 μm long perpendicular to the first line segment, with the centers of gravity being points P0, P1, and P2.

[0084] After that, a force curve was measured once in contact mode at each point. Note that the force curve measurement is performed by controlling the piezo element that drives the cantilever so that it turns back when the deflection reaches a certain value due to the tip of the cantilever coming into contact with the sample surface. This turning point is called the trigger value, and it indicates how much the voltage must increase from the deflection voltage at the start of the force curve before the cantilever turns back. In this measurement, the force curve was measured with the trigger value set to 0.2 V. Other force curve measurement conditions were a distance of 500 nm from the tip of the cantilever in a standby state to when the cantilever bends back at the trigger value, and a scan speed of 1 Hz (the speed at which the probe makes one round trip). Then, fitting based on Hertz theory was performed on each of the obtained force curves to calculate the elastic modulus. The elastic modulus (Young's modulus) according to Hertz theory was calculated using the following formula (*1).

[0085] Calculation formula (*1) F=(4 / 3)E * R 1 / 2 d 3 / 2 In the above formula (*1), F is the force applied to the sample by the cantilever at the point where the cantilever returns, E * is the composite elastic modulus, R is the radius of curvature of the tip of the cantilever (8 nm), and d is the deformation of the sample at the point where the cantilever turns back.

[0086] Then, d is calculated using the following formula (*2). Calculation formula (*2) Calculate as d=Δz-D. In the above formula (*2), Δz is the displacement of the piezoelectric element from when the tip of the cantilever contacts the sample until it bends back, and D is the amount of warping of the cantilever at the time it bends back. D was calculated using the following formula (*3).

[0087] Calculation formula (*3) D=α·ΔVdeflection In the calculation formula (*3), α is the proportionality constant of the cantilever, and ΔVdeflection represents the change in deflection voltage from when the cantilever starts to contact the sample to when it turns back.

[0088] Furthermore, F was calculated using the following formula (*4). Calculation formula (*4) F=κ·D In formula (*4), κ is the spring constant of the cantilever. Also, ΔVdeflection and Δz are measured values, so from formulas (*1) to (*4), E in formula (*1) * Furthermore, the elastic modulus (Young's modulus) Es was calculated using the following formula (*5).

[0089] Calculation formula (*5) 1 / E * =[(1-Vs 2 ) / Es]-[(1-Vi 2 ) / Ei] Vs: Poisson's ratio of the sample (fixed at 0.33 in this example); Vi: Poisson's ratio of the cantilever tip (in this example, the value for silicon is used); Ei: Young's modulus of the cantilever tip (in this example, the value for silicon is used).

[0090] The elastic modulus was measured at 70,000 points at a pitch (interval) of 0.1 μm in both the vertical and horizontal directions in a rectangular observation area (three 10 μm × 70 μm observation areas) with each of P0, P1, and P2 as the center of gravity, one side of which was 70 μm long and parallel to the first line segment, and the other side of which was 10 μm long and perpendicular to the first line segment. The average value of the elastic modulus values calculated from the force curves at a total of 210,000 points was taken as the elastic modulus of the tip surface. The standard deviation was calculated from the elastic modulus of a total of 210,000 points. The coefficient of variation of the elastic modulus of the tip surface was calculated from the average value and standard deviation of the elastic modulus values using the following formula 1. Equation (1): Coefficient of variation (%) = (standard deviation / average value of elastic modulus) × 100 The average value of the elastic modulus and the coefficient of variation of the elastic modulus were calculated for the main surface in the same manner as above.

[0091] <Evaluation 4: Evaluation of wiping performance> The elastic part 13 was gripped over its entire length in the longitudinal direction by the gripping part 801 of the evaluation device shown in Fig. 8, and the wiper blade's performance in wiping off dirt on a glass surface was evaluated by the following experiment. The gripping part gripped the elastic part 13 up to a position 10 mm from the attachment side on the main surface side, and up to a position 15 mm from the attachment side on the surface opposite to the main surface. Silicone oil (trade name: ) was applied to the entire surface of one side of the glass plate 14, which was the member to be cleaned, to simulate an oil film. Silicone oil (KF-96-50cs, manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the surface of the glass plate 14 on which the silicone oil had been applied (hereinafter also referred to as the "surface to be cleaned"). The elastic portion 13 was then brought into contact with the surface to be cleaned of the glass plate 14. FIG. 9 shows an enlarged view of the contact area between the elastic portion of the wiper blade and the surface to be cleaned. As shown in FIG. 9, the elastic portion 13 was brought into contact with the surface to be cleaned such that the angle θ between its main surface 6 and the surface to be cleaned 14-01 was 45 degrees.

[0092] Then, the glass plate 14 was reciprocated in the directions of arrows W and C in FIG. 9 at a speed of 10 mm / sec using an electric Robo Cylinder (product name: RCP4-SA5C, manufactured by IAI Corporation) 15. Then, the state of wiping of the silicone oil on the surface 14-01 to be cleaned was observed by the glass plate 1 The surface of the wiper 4 opposite to the surface 14-01 to be cleaned was visually inspected and photographed with a camera. The ratio of the area of the portion from which silicone oil was removed to the contact area of the blade 13 on the surface to be cleaned 14-01 (hereinafter also referred to as the "silicone oil removal area rate (%)") was calculated and evaluated based on the following criteria. The pressing force of the elastic part against the glass surface per meter of longitudinal length was set to two levels: 7 N / m and 15 N / m, and the silicone oil removal area rate was calculated for each level.

[0093] [Evaluation criteria] Rank A: Silicone oil film removal area rate is 95% or more Rank B: Silicone oil film removal area rate is 90% or more but less than 95% Rank C: Silicone oil film removal area rate is 85% or more but less than 90% Rank D: Silicone oil film removal area rate is 80% or more but less than 85% Rank E: Silicone oil film removal area rate is less than 50%

[0094] Examples 2 to 32 The types and amounts of various materials for the prepolymer, and the types and amounts of various materials for the curing agent were as shown in Tables 4 to 7. In addition, elastic portions were produced and evaluated in the same manner as in Example 1, except for the points noted below. In Example 3, tris(phenylisocyanate)thiophosphate (trade name: Ultite Super CAII, manufactured by Toho Chemical Industry Co., Ltd.) (TPTI) was used as the tri- or higher functional isocyanate. In Example 5, polymeric MDI (trade name: Millionate MR-400, manufactured by Tosoh Corporation) (hereinafter referred to as MR400) was used as the tri- or higher functional isocyanate. The NCO% of the prepolymer according to Example 5 was 10.2 mass%. In Example 6, glycerin (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the polyfunctional alcohol for the curing agent.

[0095] In Example 13, trimethylolpropane (manufactured by Tokyo Chemical Industry Co., Ltd.) (hereinafter also referred to as "TMP") was used as the polyfunctional alcohol having three or more functional groups for the curing agent. In Example 14, polymeric MDI (trade name: Millionate MR-200, manufactured by Tosoh Corporation) (hereinafter also referred to as "MR200") was used as the tri- or higher functional isocyanate for the prepolymer. In Example 18, polybutylene adipate polyester polyol having a number average molecular weight of 1000 (trade name: Nipporan 4009, manufactured by Tosoh Corporation) (hereinafter also referred to as "PBA1000") was used as the polyol for the curing agent. In Example 19, polyhexylene adipate polyester polyol (trade name: Nipporan 136, manufactured by Tosoh Corporation) (hereinafter also referred to as "PHA2600") having a number average molecular weight of 2600 was used as the polyol for the prepolymer.

[0096] In Example 29, polymeric MDI (trade name: Cosmonate M-200, manufactured by Mitsui Chemicals, Inc.) (hereinafter referred to as ")") was used as a trifunctional or higher polyfunctional isocyanate for the prepolymer. In Example 29, a polytetramethylene ether glycol (trade name: PTG-2000SN, manufactured by Hodogaya Chemical Co., Ltd.) having a number average molecular weight of 2000 (hereinafter also referred to as "PTG2000SN") was used as the polyol for the prepolymer. The NCO content of the prepolymer according to Example 29 was 7.9% by mass. In addition, a polytetramethylene ether glycol (trade name: PTG-1000SN, manufactured by Hodogaya Chemical Co., Ltd.) having a number average molecular weight of 1000 (hereinafter also referred to as "PTG1000SN") was used as the polyol for the curing agent. The curing time was 6 minutes. In Examples 30 to 32, the curing time of the raw material composition was also 6 minutes.

[0097] Example 33 As shown in Table 7, a prepolymer having an NCO content of 9.0% by mass was obtained using the prepolymer materials. PBA2000 is a polybutylene adipate polyester polyol (trade name: Nipporan 4010, manufactured by Tosoh Corporation) having a number average molecular weight of 2000. A curing agent was also prepared using the curing agent materials shown in Table 7. A raw material composition prepared by mixing the prepolymer and the solidifying agent was poured into a mold for forming the elastic part of the wiper blade in the same manner as in Example 1. The mixture was then cured at 130°C for 10 minutes. The mixture was then demolded and subjected to secondary curing at 130°C for 60 minutes to obtain the elastic part of this example.

[0098] Example 34 A wiper blade elastic portion was produced in the same manner as in Example 1, except that the types and amounts of various prepolymer materials and the types and amounts of various curing agent materials were as shown in Table 7. Next, the main surface and tip surface of this wiper blade elastic portion were used to obtain a wiper blade elastic portion according to this example. A low-pressure mercury ozone-less lamp (manufactured by Toshiba Lighting & Technology Corporation) with a maximum emission wavelength peak at a wavelength of 254 nm was used as the ultraviolet light source. This wiper blade elastic portion was evaluated in the same manner as in Example 1.

[0099] Examples 35-36 Wiper blades were produced in the same manner as in Example 1, except that the types and amounts of various materials for the prepolymer and the types and amounts of various materials for the curing agent were as shown in Table 7. Furthermore, the obtained wiper blades were irradiated with ultraviolet light in the same manner as in Example 34, except that the integrated light amount was changed to the values shown in Table 7, to obtain wiper blade elastic portions according to Examples 35 and 36. These wiper blade elastic portions were evaluated in the same manner as in Example 1. Example 37 A prepolymer having an NCO content of 7.0% by mass was obtained using various prepolymer materials as shown in Table 7. A curing agent was prepared using various curing agent materials as shown in Table 7. A raw material composition obtained by mixing the prepolymer and the curing agent was poured into a mold for forming the elastic portion of a wiper blade in the same manner as in Example 1 and cured at a temperature of 130°C for 10 minutes. The mixture was then demolded and subjected to secondary curing at a temperature of 130°C for 60 minutes to obtain the elastic portion of a wiper blade. The main surface and tip surface of the elastic part of the obtained wiper blade were subjected to irradiation with an integrated light dose of 1968 mJ / cm in the same manner as in Example 34. 2 The wiper blade elastic portion according to this example was thus obtained.

[0100] Example 38 The elastic portion of the wiper blade was produced and evaluated in the same manner as in Example 1, except that the types and amounts of various materials for the prepolymer and the types and amounts of various materials for the curing agent were as shown in Table 7.

[0101] Examples 39 and 40 The types and amounts of various materials for prepolymers, and the types and amounts of various materials for hardeners Wiper blades were produced in the same manner as in Example 1, except that the amounts used were as shown in Table 7. Furthermore, the obtained wiper blades were irradiated with ultraviolet light in the same manner as in Example 34, except that the integrated light amount was changed to the values shown in Table 7, to obtain wiper blade elastic portions according to Examples 39 and 40. These wiper blade elastic portions were evaluated in the same manner as in Example 1.

[0102] Example 41 A prepolymer having an NCO content of 9.0% by mass was obtained using various materials for the prepolymer as shown in Table 8. A curing agent was prepared using various materials for the curing agent as shown in Table 8. A raw material composition obtained by mixing the prepolymer and the curing agent was poured into a mold for forming the elastic part of the wiper blade in the same manner as in Example 1 and cured at a temperature of 130°C for 10 minutes. The mold was then demolded and secondary cured at a temperature of 130°C for 60 minutes to obtain a polyurethane molded article. The obtained polyurethane molded article was processed in the same manner as in Example 1 to obtain the elastic part of the wiper blade according to this example.

[0103] Examples 42 to 44 Prepolymers were prepared in the same manner as in Example 41, except that the types and amounts of various materials for the prepolymers were as shown in Table 7. The NCO content of the prepolymer according to Example 42 was 8.2% by mass, the NCO content of the prepolymer according to Example 43 was 15.0% by mass, and the NCO content of the prepolymer according to Example 44 was 18.0% by mass. In addition, curing agents were prepared in the same manner as in Example 41, except that the various materials for the curing agents and the amounts used were as shown in Table 7. Wiper blade elastic portions according to Examples 42 to 44 were produced and evaluated in the same manner as in Example 41, except that these prepolymers and curing agents were used.

[0104] Examples 45 and 46 The elastic portion of the wiper blade obtained in Example 44 was irradiated with ultraviolet rays in the same manner as in Example 34, except that the integrated light amount was set to the value shown in Table 7, to obtain elastic portions of the wiper blade according to Examples 45 and 46. The obtained elastic portions of the wiper blade were evaluated in the same manner as in Example 1.

[0105] Examples 47 to 50 Prepolymers were prepared in the same manner as in Example 41, except that the types and amounts of various materials for the prepolymers were as shown in Table 7. The NCO content of the prepolymer according to Example 47 was 10.0% by mass, the NCO content of the prepolymer according to Example 48 was 9.6% by mass, the NCO content of the prepolymer according to Example 49 was 9.3% by mass, and the NCO content of the prepolymer according to Example 50 was 9.2% by mass. In addition, curing agents were prepared in the same manner as in Example 41, except that the various materials for the curing agents and the amounts used were as shown in Table 7. Except for using these prepolymers and curing agents, elastic portions of wiper blades according to Examples 47 to 50 were produced and evaluated in the same manner as in Example 41.

[0106] Example 51 The main surface and tip surface of a wiper blade elastic part obtained in the same manner as in Example 37, within a region 2 mm from the tip edge, were immersed in 4,4'-MDI melted at 80°C for 1 minute. Thereafter, a sponge soaked in butyl acetate was used to wipe off the 4,4'-MDI adhering to the surface of the immersed portion of the wiper blade elastic part. The wiper blade elastic part was then aged for 24 hours in an environment at 23°C and 50% relative humidity, resulting in a wiper blade elastic part according to this example, in which hardened regions were formed near the tip edge of the main surface and tip surface. This wiper blade elastic part was evaluated in the same manner as in Example 1.

[0107] Example 52 The elastic part of the wiper blade according to this example was prepared in the same manner as in Example 51, except that the 4,4'-MDI adhering to the surface of the immersed part of the elastic part of the wiper blade was wiped off and then heated at a temperature of 100°C for 30 minutes, and then evaluated in the same manner as in Example 1.

[0108] Example 53 The elastic part of the wiper blade prepared in the same manner as in Example 4 was subjected to a surface treatment in the same manner as in Example 51, except that the immersion time in 4,4'-MDI was changed to 3 minutes, to obtain an elastic part of the wiper blade according to this example. This was evaluated in the same manner as in Example 1.

[0109] Example 54 The elastic part of the wiper blade according to this example was prepared in the same manner as in Example 53, except that the 4,4'-MDI adhering to the surface of the immersed part of the elastic part of the wiper blade was wiped off and then heated at a temperature of 100°C for 30 minutes, and then evaluated in the same manner as in Example 1.

[0110] Comparative Example 1 A prepolymer having an NCO content of 14.0% by mass was prepared using various prepolymer materials as shown in Table 10. A curing agent was also prepared using various curing agent materials as shown in Table 10. A raw material composition obtained by mixing the prepolymer and the curing agent was poured into a mold for molding the elastic part of a wiper blade in the same manner as in Example 1 and cured at a temperature of 130°C for 10 minutes. The molded product was then demolded and subjected to secondary curing at a temperature of 130°C for 60 minutes to obtain a polyurethane molded product. The obtained polyurethane molded product was processed in the same manner as in Example 1 to produce the elastic part of a wiper blade according to this example. The obtained wiper blade was evaluated in the same manner as in Example 1.

[0111] Comparative Example 2 A prepolymer having an NCO content of 9.0% by mass was obtained using various materials for the prepolymer as shown in Table 10. Furthermore, a curing agent was prepared using various materials for the curing agent as shown in Table 10. A wiper blade elastic portion was produced and evaluated in the same manner as in Comparative Example 1, except that the prepolymer and the curing agent were used.

[0112] Comparative Example 3 A prepolymer having an NCO content of 9.0% by mass was obtained using various materials for the prepolymer as shown in Table 10. A curing agent was also prepared using various materials for the curing agent as shown in Table 10. A wiper blade elastic portion was produced in the same manner as in Comparative Example 1, except that the prepolymer and the curing agent were used. The obtained wiper blade elastic portion was exposed to an accumulated light dose of 8200 mJ / cm. 2 Except for the above, ultraviolet light was irradiated in the same manner as in Example 34 to obtain a wiper blade elastic portion according to this comparative example. The obtained wiper blade elastic portion was evaluated in the same manner as in Example 1.

[0113] Comparative Example 4 To 100 parts by mass of natural rubber, 48.0 parts by mass of carbon black (trade name: Toka Black #7360SB, manufactured by Tokai Carbon Co., Ltd.), 5.0 parts by mass of zinc oxide (trade name: Zinc oxide type 2, manufactured by Sakai Chemical Industry Co., Ltd.), 1.0 part by mass of zinc stearate (trade name: SZ-2000, manufactured by Sakai Chemical Industry Co., Ltd.), and 20 parts by mass of calcium carbonate (trade name: Nanox #30, manufactured by Maruo Calcium Co., Ltd.) were added, and the mixture was kneaded for 15 minutes in an internal mixer adjusted to a temperature of 50°C to obtain a kneaded product. To the kneaded mixture, 1.2 parts by mass of sulfur and 4.5 parts by mass of tetrabenzyl thiuram sulfide (TBzTD) (trade name: Percasit TBzTD, manufactured by Frekins) were added as vulcanizing agents. The mixture was then kneaded for 10 minutes in a two-roll mill cooled to a temperature of 25°C to obtain a rubber composition. The obtained rubber composition was placed in a mold for forming the elastic part of a wiper blade, compression-vulcanized at 170°C for 20 minutes, and then demolded to obtain the elastic part of a wiper blade. The obtained elastic part of the wiper blade was evaluated in the same manner as in Example 1.

[0114] The evaluation results of each of the above examples and comparative examples are shown in Tables 4 to 10.

[0115] [Table 4]

[0116] [Table 5]

[0117] [Table 6]

[0118] [Table 7]

[0119] [Table 8]

[0120] [Table 9]

[0121] [Table 10] [Explanation of symbols]

[0122] 1: Grip portion, 2: Elastic portion, 3: Support portion, 4: Support grip portion, 5: Cleaned member, 6: Main surface, 8: Tip surface, 9: Tip edge, 10: First line segment, 11: Second line segment, 12: Observation area, 13: Wiper blade elastic portion, 14: Glass plate, 15: Electric ROBO Cylinder

Claims

1. a grip portion to be held by hand; an elastic portion supported by the grip portion and pressed against the surface to be cleaned; A cleaning wiper blade that cleans the surface of a member to be cleaned by bringing a part of the elastic portion into contact with the surface of the member to be cleaned, When the side of the elastic portion farthest from the grip portion is defined as the tip side of the wiper blade, The elastic portion has, at the tip end side, a main surface facing the member to be cleaned and a tip end surface forming a tip end edge together with the main surface, Assuming that a first line segment is drawn on the tip surface parallel to the tip edge at a distance of 10 μm from the tip edge, The length of the first line segment is L1, The points (1 / 8)L1, (1 / 2)L1, and (7 / 8)L1 from one end side on the first line segment are designated as P0, P1, and P2, respectively; The tip surface has a center of gravity at each of the points P0, P1, and P2, and one side is 70 μm long and parallel to the first line segment, and one side is 10 μm long and perpendicular to the first line segment. When the elastic modulus of the tip surface at 70,000 points at a pitch of 0.1 μm is measured using a scanning probe microscope, the average value of a total of 210,000 elastic modulus values obtained is 15 MPa to 470 MPa, and The coefficient of variation of the elastic modulus is 17.6% or less, Assuming that a second line segment is drawn on the main surface parallel to the tip-side edge and at a distance of 10 μm from the tip-side edge, The length of the second line segment is L2, The points (1 / 8)L2, (1 / 2)L2, and (7 / 8)L2 from one end side on the second line segment are designated as P3, P4, and P5, respectively; For each of three rectangular observation regions on the main surface, each of which has a center of gravity at each of the points P3, P4, and P5, and which has one side parallel to the second line segment and a length of 70 μm and one side perpendicular to the second line segment and a length of 10 μm, the elastic modulus of the main surface is measured at 70,000 points at a pitch of 0.1 μm using a scanning probe microscope, and the average value of a total of 210,000 elastic modulus values obtained is 15 MPa to 470 MPa, and A cleaning wiper blade characterized in that the coefficient of variation of the elastic modulus is 17.6% or less.

2. The elastic portion contains polyurethane, The cleaning wiper blade according to claim 1 , wherein the polyurethane comprises a reaction product of a composition containing at least one of an alcohol including a trifunctional or higher polyfunctional alcohol and an isocyanate compound including a trifunctional or higher polyfunctional isocyanate.

3. The elastic portion contains polyurethane, 3. The cleaning wiper blade according to claim 1 or 2, wherein the polyurethane comprises a reaction product of a composition containing an isocyanate compound including a diisocyanate and a tri- or higher functional isocyanate, and an alcohol including a tri- or higher functional alcohol.

4. Assuming that a line segment is drawn on the tip surface and the main surface of the elastic portion, parallel to the tip edge, and at a distance of 0.5 mm from the tip edge, the length of the line segment is defined as L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end side on the line segment are defined as P0', P1', and P2', respectively; A direct sample introduction method in which the sample sampled at each of the P0', P1', and P2' of the tip surface and the main surface is heated and vaporized in an ionization chamber, and the sample molecules are ionized. The mass spectrometer was used, and the temperature was increased at a rate of 10°C / s up to 1000°C. The detected amount of all ions is M1, M2 is the integrated intensity of a peak in the extracted ion thermogram corresponding to the m / z value range derived from the tri- or higher functional isocyanate; When the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values derived from the diisocyanate is M3, In the tip surface, M2 / M1 is 0.0010 to 0.0150, and M3 / M1 is 0.0200 to 0.1100, 4. The cleaning wiper blade according to claim 3, wherein, on said main surface, M2 / M1 is 0.0010 to 0.0150, and M3 / M1 is 0.0200 to 0.1100.

5. Assuming that a line segment is drawn on the tip surface and the main surface of the elastic portion, parallel to the tip edge, and at a distance of 0.5 mm from the tip edge, the length of the line segment is defined as L', and points 1 / 8L', 1 / 2L', and 7 / 8L' from one end side on the line segment are defined as P0', P1', and P2', respectively; When samples sampled at P0′, P1′, and P2′ of the tip surface and the main surface are measured by pyrolysis GC / MS, At the tip surface, the concentration of the trifunctional or higher polyfunctional alcohol in the polyurethane is 0.04 mmol / g to 0.39 mmol / g, 5. The cleaning wiper blade according to claim 2, wherein the concentration of the tri- or higher functional alcohol in the polyurethane on the main surface is 0.04 mmol / g to 0.39 mmol / g.

6. The cleaning wiper blade according to any one of claims 2 to 5, wherein the tri- or higher functional alcohol includes at least one selected from the group consisting of trimethylolpropane and glycerin.

7. The cleaning wiper blade according to any one of claims 2 to 6, wherein the trifunctional or higher polyfunctional isocyanate is at least one selected from the group consisting of triphenylmethane-4,4',4''-triisocyanate (TTI), tris(phenylisocyanate) thiophosphate (TPTI), and polymeric MDI.

8. In measuring the elastic modulus of the tip surface, The average value of the elastic modulus is 32 MPa or more and 62 MPa or less, In measuring the modulus of elasticity of the main surface, The average value of the elastic modulus is 32 MPa or more and 62 MPa or less. The cleaning wiper blade according to any one of claims 1 to 7.

9. In measuring the elastic modulus of the tip surface, The coefficient of variation of the elastic modulus is 6.0% or less, In measuring the modulus of elasticity of the main surface, The cleaning method according to any one of claims 1 to 8, wherein the coefficient of variation of the elastic modulus is 6.0% or less. Cleaning wiper blades.

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