Vehicle wiper blades

Abstract

To provide a wiper blade for a vehicle, capable of exhibiting excellent wiping performance.SOLUTION: In a wiper blade for a vehicle, the surface of a member to be cleaned is cleaned by bringing one portion of a lip part into contact with the surface. A polyurethane in the lip part includes the reaction product of a composition which includes a reactant of compositions including an isocyanate compound including a diisocyanate and a tri- or higher functional polyfunctional isocyanate; and an alcohol including a tri- or higher functional polyfunctional alcohol. The diisocyanate has an aromatic ring in its molecule. When the detected quantity of all ions is represented by M1, the tri- or higher functional polyfunctional isocyanate is represented by M2, and the diisocyanate is represented by M3, M2 / M1 is 0.001-0.028, M3 / M1 is 0.020-0.110, and M2 / M3 is 0.013-0.300. The concentration of the tri- or higher functional polyfunctional alcohol in the polyurethane is 0.12 mmol / g-0.65 mmol / g.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Vehicle wiper blades are made of natural rubber, chloroprene rubber, and other rubbers. These rubbers contain unsaturated bonds and are therefore prone to deterioration. Patent Document 1, one of the prior art documents, proposes the use of polyurethane, a material that does not contain unsaturated bonds. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-51894 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, glass surfaces have often been treated with water-repellent coatings or wax coatings to ensure good visibility. While these treatments improve wiping performance in some areas, they can cause uneven contact with the glass surface, resulting in chattering. The noise caused by the uneven contact can be unpleasant for the driver, and the chattering itself can lead to reduced wiping performance. According to the inventors' research, polyurethane wiper blades such as those described in Patent Document 1 still have room for improvement in terms of their ability to wipe away raindrops and other debris from the windshield. One aspect of the present disclosure is directed to providing a vehicle wiper blade that can exhibit excellent wiping performance. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, a blade support; Neck and The blade support Applicable a lip portion pivotally connected to the neck, A wiper blade for a vehicle that cleans a surface of a member to be cleaned by bringing a part of the lip portion into contact with the surface of the member to be cleaned, The lip portion 、 Contains polyurethane, The polyurethane is 、 J Isocyanate compounds including isocyanates and trifunctional or higher polyfunctional isocyanates 、 3 Multifunctional alcohols , low molecular weight diols and polyols Contains alcohol ,and, catalyst The composition includes reactants 、 Applicable The polyurethane is heated to 1000°C at a heating rate of 10°C / s using a direct sample introduction mass spectrometer, which heats and vaporizes the sample in the ionization chamber and ionizes the sample molecules. The detected amount of all ions is M1. The integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value range derived from the trifunctional or higher polyfunctional isocyanate is defined as M2. When the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values ​​derived from diisocyanates is M3, M2 / M1 、 0.001 to 0.028, M3 / M1 、 0.020 to 0.110, M2 / M3 、 0.013 to 0.300, The concentration of the trifunctional or higher polyfunctional alcohol in the polyurethane is 0.12 mmol / g to 0.65 mmol / g. the law of nature, the diisocyanate is at least one selected from the group consisting of 4,4'-diphenylmethane diisocyanate, toluene diisocyanate, m-xylylene diisocyanate, and 1,5-naphthalene diisocyanate; the tri- or higher functional isocyanate is at least one selected from the group consisting of polymeric MDI, triphenylmethane-4,4',4"-triisocyanate, and tris(phenylisocyanate)thiophosphate; the trifunctional or higher polyfunctional alcohol is at least one selected from the group consisting of trimethylolpropane, glycerin, and pentaerythritol; the low molecular weight diol is 1,4-butanediol; the polyol is at least one selected from the group consisting of polybutylene adipate polyester polyol, polyhexylene adipate polyester polyol, and polytetramethylene ether glycol; The catalyst is N,N'-dimethylhexanolamine. R 、 A wiper blade for a vehicle is provided. [Effects of the Invention]

[0006] According to one aspect of the present disclosure, a wiper blade for a vehicle that can exhibit excellent wiping performance can be provided. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram of a wiper blade. [Figure 2] 2(a) and 2(b) are explanatory diagrams showing the state of the wiper blade during cleaning. [Figure 3] An enlarged view of the vicinity of the first edge. [Figure 4] An enlarged view of the vicinity of the first line segment. [Figure 5] 5(a) and (b) are binarized images of Example 1 and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the present disclosure, unless otherwise specified, the expressions "XX or more and YY or less" and "XX to YY" representing a numerical range mean a numerical range including the endpoints, that is, the lower limit and the upper limit. When numerical ranges are stated in stages, the upper and lower limits of each numerical range can be combined in any way. The inventors have considered that, in conventional polyurethane wiper blades, the hard segment portion and the soft segment portion in the polyurethane transmit force to the surface to be cleaned differently, which causes, for example, streaky unwiped areas. Based on these considerations, further investigation led to the discovery that in order to further improve wiping performance, it is effective for the elastic portion of the wiper blade to contain a specific polyurethane. This specific polyurethane is thought to suppress aggregation of hard segments, resulting in uniform transmission of force to the surface to be cleaned in the longitudinal (width) direction of the wiper blade, effectively suppressing the occurrence of streaks in the wiped area.

[0009] <Configuration of vehicle wiper blades> The vehicle wiper blade (hereinafter simply referred to as wiper blade) according to the present disclosure can be used in equipment such as vehicles such as automobiles, transportation equipment such as airplanes and ships, and industrial machinery and equipment such as construction machinery. As shown in Fig. 1, the wiper blade includes a blade support portion 1 and a lip portion 3 pivotally connected to the blade support portion via a neck 2. The wiper blade is formed with a substantially uniform cross-sectional shape in the longitudinal direction. The shape of the lip portion 3 is not particularly limited, but for example, the cross section perpendicular to the longitudinal direction of the wiper blade may have a shape in which the width gradually decreases from the side closer to the blade support portion 1 toward the side away from the blade support portion 1. The wiper blade cleans the surface of a member to be cleaned, typically a glass surface, by bringing a part of the lip into contact with the surface of the member to be cleaned. For example, the neck 2 may be configured so that its width is narrower than the blade support portion 1 and the lip portion 3 in a cross section perpendicular to the longitudinal direction of the wiper blade. As a result, as shown in FIG. 2, the lip portion 3 is inclined in the wiping direction and comes into contact with the surface of the member to be cleaned.

[0010] 2(a) and 2(b) in FIG. 2 are explanatory diagrams showing the state of the wiper blade during the cleaning process. R indicates the cleaning direction of the wiper blade. This indicates that the surface that comes into contact with the object being cleaned changes depending on the cleaning direction. For example, in FIG. 2(a), the neck 2 acts to move the lip 3 of the wiper blade. The lip portion 3 is inclined to the right side of the drawing, and the right side of the drawing of the lip portion 3 comes into contact with the member 10 to be cleaned. On the other hand, in FIG. 2(b), the neck 2 causes the lip portion 3 of the wiper blade to tilt to the left in the drawing, and the left side of the lip portion 3 in the drawing comes into contact with the member 10 to be cleaned. In this way, by switching from cleaning in the direction of arrow R in Figure 2(a) to cleaning in the direction of arrow R in Figure 2(b), the surface that comes into contact with the object to be cleaned switches from the right side of the lip portion 3 on the paper to the left side on the paper.

[0011] As mentioned above, it is believed that the streaky unwiped residue occurs in conventional polyurethane wiper blades due to the difference in how force is transmitted to the member being cleaned between the hard segment and the soft segment in the polyurethane. The cause of this is thought to be as follows: It is believed that the polyurethane used in conventional wiper blades has progressed in hard segment aggregation, resulting in clumping of hard segments. As a result, at the microscopic polymer level, the difference in hardness between the hard and soft segments is evident, resulting in uneven hardness. When the wiper blade is brought into contact with the object to be cleaned in this state, areas of strong and weak contact force will appear irregularly, and it is thought that streaks will be left unwiped during the cleaning process (wiping operation). Therefore, the inventors believed that the above-mentioned hardness unevenness could be resolved by finely and uniformly dispersing the hard segments in the polyurethane. Based on this consideration, by specifying the composition of the polyurethane, it became possible to finely and uniformly disperse the hard segments in the polyurethane, thereby further improving the wiping performance of the member to be cleaned.

[0012] The lip portion of the present disclosure comprises polyurethane; The polyurethane contains 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. The diisocyanate also has an aromatic ring in the molecule. In addition, the polyurethane was heated to 1000°C at a heating rate of 10°C / s using a direct sample introduction mass spectrometer in which the sample was heated and vaporized in an ionization chamber and the sample molecules were ionized. The detected amount of all ions is M1. The integrated intensity of the peak in the extracted ion thermogram corresponding to the m / z value range derived from the trifunctional or higher polyfunctional isocyanate is defined as M2. When the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values ​​derived from diisocyanates is M3, M2 / M1 is 0.001 to 0.028, M3 / M1 is 0.020 to 0.110, M2 / M3 is 0.013 to 0.300, The concentration of the tri- or higher functional alcohol in the polyurethane is 0.12 mmol / g to 0.65 mmol / g.

[0013] This will be explained in detail below. Hard segments are mainly formed by the aggregation of diisocyanates through interactions between urethane bonds or between aromatic rings. Hard segments tend to grow larger when they can stack regularly. Therefore, by disrupting this regularity, it is possible to achieve finer hard segments. Therefore, as described above, by using a composition containing a trifunctional or higher polyfunctional isocyanate and a trifunctional or higher polyfunctional alcohol in an appropriate concentration range, orientation is suppressed by steric hindrance, making it difficult for the hard segments to aggregate, resulting in finer hard segments and uniform dispersion. will be done. As a result, the contact force between the lip and the object to be cleaned is uniform across the entire length of the wiper blade, allowing the contact portion to move uniformly across the surface of the object to be cleaned, thereby achieving excellent wiping performance with no uneven wiping across the entire length of the wiper blade.

[0014] When the M2 / M1 ratio is 0.001 or more, a structure derived from a tri- or higher functional polyfunctional isocyanate having low crystallinity is introduced into the polyisocyanate that forms the hard segment, which makes it possible to suppress aggregation of the hard segment and to disperse the hard segment finely and uniformly. When the M2 / M1 ratio is 0.028 or less, aggregation between low-molecular-weight polyfunctional components can be suppressed, and aggregation of hard segments can be suppressed. When the M2 / M1 ratio is 0.015 or less, aggregation can be suppressed to an even greater extent. If the M3 / M1 ratio is 0.020 or more, the polymer is likely to be polymerized in the curing reaction, and the abrasion resistance can be improved. It is also preferable that the ratio is 0.040 or more. Since the higher the diisocyanate concentration, the more aggregation of hard segments tends to occur, M3 / M1 is set to 0.110 or less. By setting the ratio to 0.110 or less, aggregation of hard segments can be further suppressed. Furthermore, it is preferably set to 0.100 or less. When M2 / M3 is 0.013 or more, a sufficient amount of tri- or higher-functional isocyanate is present relative to the diisocyanate, thereby suppressing crystallization caused by the diisocyanate and making it possible to suppress aggregation of the hard segments. On the other hand, if the M2 / M3 ratio is 0.300 or less, aggregation between low-molecular-weight polyfunctional components can be suppressed, and aggregation of hard segments can be suppressed. If the ratio is 0.150 or less, aggregation can be suppressed to an even greater extent.

[0015] Also, the M2 / M1 is 0.001 to 0.015, The M3 / M1 is 0.040 to 0.100, The M2 / M3 is 0.013 to 0.150, The concentration of the tri- or higher functional alcohol in the polyurethane is preferably 0.22 mmol / g to 0.39 mmol / g.

[0016] The concentration of the tri- or higher functional alcohol in the polyurethane is calculated by the following formula (1). When the concentration of the tri- or higher functional alcohol is within the above range, the effect of inhibiting hard segment aggregation is high. That is, the concentration of the tri- or higher functional alcohol in the polyurethane is 0.12 mmol / g to 0.65 mmol / g, and preferably 0.22 mmol / g to 0.39 mmol / g. Equation (1): 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)]

[0017] The polyurethane is preferably a polyurethane elastomer. Polyurethane elastomers are obtained primarily from raw materials such as polyols, chain extenders, polyisocyanates, catalysts, and other additives. The polyurethane elastomer is a block copolymer consisting of a hard segment and a soft segment. The hard segment is generally composed of a polyisocyanate and a chain extender containing a short-chain diol. On the other hand, the soft segment is generally composed of a long-chain polyol such as a polyester polyol, a polyether polyol, or a polycarbonate polyol and a polyisocyanate.

[0018] As the polyisocyanate, a diisocyanate and a tri- or higher functional isocyanate are used in combination. Examples of diisocyanates include the following: 4,4'-diphenylmethane diisocyanate (4,4'-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), tetramethylxylene diisocyanate (TMXDI), carbodiimide-modified MDI.

[0019] The diisocyanate used has an aromatic ring in the molecule, and by using the diisocyanate containing the aromatic ring, good mechanical properties and high reactivity can be obtained. The diisocyanate preferably has a structure in which NCO is directly bonded to the aromatic ring, which further suppresses aggregation of the hard segments and allows for more fine dispersion.

[0020] Examples of the tri- or higher functional isocyanate include the following: Polymeric MDI, triphenylmethane-4,4',4''-triisocyanate (TTI), tris(phenylisocyanate) thiophosphate (TPTI), 4-isocyanatomethyl-1,8-octamethylene diisocyanate, 1,3,6-hexamethylene triisocyanate, trimethylbenzene triisocyanate, diphenylmethane-2,4-4'-triisocyanate. The tri- or higher functional isocyanate is preferably at least one selected from the group consisting of polymeric MDI, triphenylmethane-4,4',4''-triisocyanate, and tris(phenylisocyanate)thiophosphate. The trifunctional or higher polyfunctional isocyanate is preferably at least one selected from the group consisting of polymeric MDI and tris(phenylisocyanate)thiophosphate. The isocyanate has a methylene group or an ether group between NCO groups. join Since the distance between urethane bonds can be appropriately maintained, this is more preferable for suppressing aggregation of hard segments.

[0021] The polymeric MDI is represented by the following chemical formula (1) and chemical formula (1)'. In the chemical formula (1)′, n is preferably 1 or more and 4 or less. Chemical formula (1) is the case where n is 1 in chemical formula (1)'.

[0022] [ka]

[0023] Branching with trifunctional or higher polyfunctional alcohols suppresses crystallization and creates hard segments. This can suppress aggregation. On the other hand, if the number of branches is too large, the density of urethane bonds around the trifunctional or higher polyfunctional alcohol increases, and the hard segments tend to aggregate easily. Therefore, it is preferable to use a trifunctional alcohol among the trifunctional or higher polyfunctional alcohols. Among these, alcohols represented by the following formula (a) or (b) are preferred, which have a methylene group adjacent to the hydroxyl group and can maintain an appropriate distance between urethane bonds. Specific examples of trifunctional or higher polyfunctional alcohols include trimethylolethane (R1 in the following formula (a) is CH3), trimethylolpropane (TMP: R1 in the following formula (a) is C2H5), glycerin, pentaerythritol, and sorbitol. The tri- or higher functional alcohol is preferably at least one selected from the group consisting of alcohols represented by the following formulae (a) and (b), glycerin, and pentaerythritol. The tri- or higher functional alcohols may be used alone or in combination of two or more.

[0024] [ka]

[0025] In the formulas (a) and (b), R1 and R2 each independently represent H, CH3, or C2H5.

[0026] Examples of the polyol 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 glycol; and polycarbonate diols. These can be used alone or in combination of two or more.

[0027] Among the above polyols, polyester polyols using adipate are preferred because they give polyurethane elastomers with excellent mechanical properties. In particular, those having alkylene groups with 4 or more carbon atoms, such as polybutylene adipate polyester polyol and polyhexylene adipate polyester polyol, are preferred. Furthermore, it is also preferred to use polyols having alkylene groups with different carbon numbers, such as polybutylene adipate polyester polyol and polyhexylene adipate polyester polyol. The use of these different types of polyols can improve the suppression of crystallization of soft segments, making it difficult for soft segments to aggregate, thereby further improving the dispersibility of hard segments.

[0028] As the chain extender, a diol capable of extending the polyurethane elastomer chain or a polyfunctional alcohol having three or more functional groups can 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 can be used alone or in combination of two or more.

[0029] The catalyst can be a commonly used catalyst for curing polyurethane elastomers, such as a tertiary amine catalyst, and specific examples include the following: aminoalcohols such as dimethylethanolamine, N,N,N'-trimethylaminopropylethanolamine, and N,N'-dimethylhexanolamine; trialkylamines such as triethylamine; tetraalkyldiamines such as N,N,N'N'-tetramethyl-1,3-butanediamine; triethylenediamine, piperazine-based compounds, and triazine-based compounds. Organic acid salts of metals such as potassium acetate and potassium alkali octylate can also be used. 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.

[0030] The raw material constituting the lip portion may contain additives such as pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers, and light stabilizers, as required.

[0031] <Wiper blade manufacturing method> The method for manufacturing the wiper blade is not particularly limited and can be selected from known methods. For example, the lip portion can be obtained by injecting a polyurethane elastomer raw material composition into a cavity in a mold for a wiper blade and curing it by heating. The lip portion may also be cut at its tip to form a desired shape, thereby enabling the lip portion to be molded with a high degree of smoothness on the contact surface with the member to be cleaned. Alternatively, a wiper blade may be produced by producing a pair of tandem molded bodies formed with the lip portions facing each other and abutting against each other, and then cutting the bodies in the longitudinal direction.

[0032] <The entire process, including the wiper arm> The wiper blade of the present disclosure can be used in various types of wiper devices, such as tandem and opposing wiping types. [Example]

[0033] 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.

[0034] Example 1 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 10.6% by mass.

[0035] [Table 1]

[0036] A curing agent was prepared by mixing the materials listed in Table 2 below.

[0037] [Table 2]

[0038] The prepolymer and the curing agent were mixed to prepare a polyurethane raw material composition. This raw material composition was injected into the cavity of a mold for forming a vehicle wiper blade and cured at 130°C for 2 minutes. The mold was then demolded to obtain a polyurethane molded article. Prior to injecting the raw material composition, a mold release agent A was applied to the mold cavity. The mold release agent A was a mixture of the materials shown in Table 3 below.

[0039] [Table 3]

[0040] The lip tip of the polyurethane molded article was cut to obtain a wiper blade according to this example. The thickness of the lip tip was 0.6 mm, and the length in the longitudinal direction was 450 mm. The wiper blade thus obtained was subjected to the following evaluations.

[0041] [Evaluation 1: Measurement of hard segment size] The size of the hard segments was measured using a scanning probe microscope (SPM) (trade name: MFP-3D-Origin, manufactured by Oxford Instruments) by the following method. The sample preparation method is as follows. Here, as shown in Figures 2(a) and 2(b), the lip portion 3 of the vehicle wiper blade has a first tapered surface 5 and a second tapered surface 6 opposite the first tapered surface 5 that constitute the tapered portion 4 and come into contact with the member to be cleaned 10, and a tip surface 7 that, together with the first tapered surface 5 and the second tapered surface 6, constitutes a first edge 8 and a second edge 9 on the side of the lip portion 3 that is farthest from the blade support portion 1 (see Figures 1 and 3 for the first edge, second edge, and tip surface).

[0042] The inventors observed the behavior of the reciprocating wiper blade during cleaning and confirmed that when cleaning, the wiper blade comes into contact with the object being cleaned in areas on the first and second tapered surfaces of the lip portion, centered approximately 10 μm from the first edge and second edge, respectively. As shown in Figures 3 and 4, a first line segment 11 with a length of L1 was drawn parallel to the first edge on the first tapered surface of the resulting wiper blade, with a distance of 10 μm from the first edge. Three 2 mm square measurement samples were cut out from one end of the first line segment, with centers of gravity at points (1 / 8)L1, (1 / 2)L1, and (7 / 8)L1, respectively, and with P0, P1, and P2 as their centers of gravity. Next, a 100 μm square, 1 μm thick polyurethane slice was cut out from each measurement sample at -50°C using a cryomicrotome (UC-6 (product name), manufactured by Leica Microsystems) with centers of gravity at P0, P1, and P2, and with a 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 to stand for 24 hours in an environment at room temperature of 25°C and humidity of 50%. Next, the silicon wafer with the measurement sample placed on it was set 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 set on the stage of the SPM device. The normal noise method confirmed the following (spring constant: 30.22 nN / nm, proportionality constant: 82.59 nm / V). The cantilever was tuned in advance to determine its resonance frequency (285 KHz (first order) and 1.60 MHz (higher order)). The SPM measurement mode was AM-FM mode, the cantilever free amplitude was 3V (primary) and 25mV (higher order), and the set point amplitude was 2V (primary). Scanning was performed in a 1μm x 1μm square field of view at a scan rate of 1Hz with 256 vertical and 256 horizontal scan points, and three phase images (256 grayscale levels) were obtained. The field of view was selected so that P0, P1, and P2 of each measurement sample were in the center of the field of view and one side was parallel to the first line segment. Each of the obtained phase images was binarized using an image processing analysis system (trade name: Luzex-AP, manufactured by Nireco Corporation). Specifically, the phase images were binarized using the binarization setting function of the image processing analysis system. The threshold value in the binarization setting function was set to 85 (the 85th of 256 gradations). This operation resulted in a binarized image in which the soft segments were displayed in black and the hard segments were displayed in white. As examples, FIG. 5(a) shows the binarized image of Example 1, and FIG. 5(b) shows the binarized image of Comparative Example 1.

[0043] The size of the hard segments in the resulting binarized image was measured using the image processing and analysis system described above, using the "circle equivalent diameter" parameter. Similarly to the first tapered surface, three binarized images were also prepared for the second tapered surface, and the size of the hard segments in each binarized image was measured. The arithmetic mean value of the sizes of all the hard segments measured from the six binarized images thus obtained was defined as the size of the hard segments in the present disclosure.

[0044] [Evaluation 2: Measurement of M1, M2, and M3] M1–M3 were measured using the direct sample introduction (DI) method, in which the sample was directly introduced into the ion source without passing through a gas chromatograph (GC). The instrument used was an ion trap GC / MS (POLARIS Q, Thermo Fisher Scientific) and a Direct Exposure Probe (DEP) was used as the direct introduction probe. A 0.1 μg sample was measured at each of P0, P1, and P2 of the first tapered surface and the second tapered surface described in Evaluation 1 by the following method. That is, the collected sample was fixed to a filament located at the tip of the probe and directly inserted into the ionization chamber. Then, it was rapidly heated from room temperature to 1000°C at a constant temperature increase rate (10°C / s), and the vaporized gas was detected by a mass spectrometer.

[0045] The amount of detected ions, M1, was defined as the sum of the integrated intensities of all peaks in the obtained total ion current thermogram, the sum of the integrated intensities of the peaks in the extracted ion thermogram of m / z values ​​derived from trifunctional or higher polyfunctional isocyanates was defined as M2, and the integrated intensities of the peaks in the extracted ion thermogram corresponding to the range of m / z values ​​derived from diisocyanates was defined as M3. Using the values ​​of M1, M2, and M3, (M2 / M1), (M3 / M1), and (M2 / M3) were calculated. The arithmetic mean values ​​of all measured values ​​obtained from the samples P0, P1, and P2 of the first tapered surface and the second tapered surface were defined as (M2 / M1), (M3 / M1), and (M2 / M3) in the present disclosure.

[0046] In this example, the elastic portion made of polyurethane synthesized using polymeric MDI as a trifunctional or higher polyfunctional isocyanate has an m / z value in the range of 380.5 to 381.5 indicating n=1 in the structure represented by the above chemical formula (1)', and an m / z value in the range of 511.5 to 512.5 indicating n=2 in the extracted ion thermogram obtained by the above analysis. Peaks derived from cationized polymeric MDI were detected, with peak tops at m / z values ​​in the range of 642.5 to 643.5, which indicates n = 3, and m / z values ​​in the range of 773.5 to 774.5, which indicates n = 4. Therefore, in this example, the sum of the integrated intensities of the respective peaks was defined as (M2).

[0047] In other examples described later, TTI used as a trifunctional or higher polyfunctional isocyanate has the structure shown in the following chemical formula (2). In the elastic portion made of polyurethane synthesized using TTI, a peak derived from a cationized product of TTI was detected in the extracted ion thermogram obtained by the above analysis, with a peak top in the m / z range of 366.5 to 367.5. Therefore, in these examples, the integrated intensity of this peak was designated M2.

[0048] [ka]

[0049] Similarly, in the examples described below, TPTI used as the trifunctional or higher polyfunctional isocyanate has a structure represented by the following chemical formula (3). In the elastic portion made of polyurethane synthesized using TPTI, a peak derived from the cationized product of TPTI was detected in the extracted ion thermogram obtained by the above analysis, with the peak top in the m / z range of 464.5 to 465.5. Therefore, in these examples, the integrated intensity of this peak was designated M2.

[0050] [ka]

[0051] On the other hand, 4,4'-MDI used as the diisocyanate in this example has the structure shown in the following chemical formula (7). In the elastic part made of polyurethane synthesized using 4,4'-MDI, a peak derived from the cationized product of 4,4'-MDI was detected in the extracted ion thermogram obtained by the above analysis, with the peak top at m / z 249.5 to 250.5. Therefore, the integrated intensity of this peak was designated as M3.

[0052] [ka]

[0053] In other examples, toluene diisocyanate (TDI) used as the diisocyanate has the structure shown in the following chemical formulas (4a) and (4b). In the elastic part made of polyurethane synthesized using TDI, a peak derived from the cationized product of TDI was detected in the extracted ion thermogram obtained by the above analysis, with the peak top in the m / z range of 173.5 to 174.5. Therefore, the integrated intensity of this peak was designated as M3.

[0054] [ka]

[0055] The diisocyanate m-xylylene diisocyanate (XDI) has the structure shown in the following chemical formula (5). In the elastic part made of polyurethane synthesized using XDI, a peak derived from the cationized product of XDI was detected in the extracted ion thermogram obtained by the above analysis, with a peak top in the m / z range of 187.5 to 188.5. Therefore, the integral value of this peak was designated as M3.

[0056] [ka]

[0057] Furthermore, the diisocyanate 1,5-naphthalene diisocyanate (NDI) has the structure shown in chemical formula (6). In the elastic part made of polyurethane synthesized using NDI, a peak derived from the cationized product of NDI was detected in the extracted ion thermogram obtained by the above analysis, with a peak top in the m / z range of 209.5 to 210.5. Therefore, the integrated intensity of this peak was designated as M3.

[0058] [ka]

[0059] [Evaluation 3: 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 positions: Samples were taken at P0, P1 and P2 on the first tapered surface and the second tapered surface, and measurements were made using the following method. Device: Thermal decomposition equipment: Product name: EGA / PY-3030D, manufactured by Frontier Labs Gas chromatography equipment: TRACE1310 gas chromatograph, Thermo Fisher Scientific Mass spectrometer: 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

[0060] 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 value of all the measured values ​​obtained from each of the samples P0, P1, and P2 of the first tapered surface and the second tapered surface was used as the concentration of the polyfunctional alcohol in this disclosure.

[0061] <Evaluation 4: Evaluation of wiping performance> The wiping performance of wiper blades was evaluated using the testing equipment for the wiping performance test described in Japanese Industrial Standards (JIS) D5710:1998 (Automotive parts - Wiper arms and wiper blades). In this test, the wiper blade was attached, water was sprayed in a mist on the glass surface to be cleaned, and the wiper blade was then moved back and forth once, after which the state of wiping off the water from the glass surface was visually confirmed and evaluated according to the following criteria.

[0062] [Wipe-off conditions] Load applied to wiper blade: 10N / m Wiper blade reciprocating speed: 50 times / min [Evaluation criteria] Rank A: One or less hairline (a very thin streak of 0.5 mm or less) and zero heavy lines (a thin streak of 1 mm or less) or wide lines (a band of 1-20 mm wide, including several hairlines or heavy lines, or thin film-like areas). Rank B: 2 hairlines and 0 heavy or wide lines Rank C: 2 hairlines, 1 heavy line, and 0 wide lines Rank D: 3 hairlines, 1 heavy line, and 0 wide lines Rank E: 4 or more hairlines, or 2 or more heavy lines, or One or more wide lines

[0063] [Examples 2 to 48 and Comparative Examples 1 to 6] A prepolymer and a curing agent were obtained, and a wiper blade was obtained in the same manner as in Example 1, except that the ingredients and amounts were changed as shown in Table 4 or Table 5. The obtained wiper blade was evaluated in the same manner as in Example 1. Examples 2, 8 to 10, 12, 17 to 19 and 40 were evaluated as reference examples.

[0064] Details of the materials used other than those shown in Example 1 are shown below. Polybutylene adipate polyester polyol with a number average molecular weight of 1000 (trade name: Nipporan 4009, manufactured by Tosoh Corporation) (hereinafter referred to as PBA1000) Polyhexylene adipate polyester polyol with a number average molecular weight of 1,000 (trade name: Nipporan 164, manufactured by Tosoh Corporation) (hereinafter referred to as PHA1000) Polyhexylene adipate polyester polyol having a number average molecular weight of 2600 (trade name: Nipporan 136, manufactured by Tosoh Corporation) (hereinafter referred to as PHA2600) Polyhexylene adipate polyester polyol having a number average molecular weight of 4500 (product name: HS2H-451A, manufactured by Toyokuni Oil Mills Co., Ltd.) (hereinafter referred to as PHA4500) Polytetramethylene ether glycol with a number average molecular weight of 1000 (trade name: PTG-1000SN, manufactured by Hodogaya Chemical Co., Ltd.) (hereinafter referred to as PTMG1000) Polytetramethylene ether glycol with a number average molecular weight of 2000 (trade name: PTG-2000SN, manufactured by Hodogaya Chemical Co., Ltd.) (hereinafter referred to as PTMG2000) Glycerin (Tokyo Chemical Industry Co., Ltd.) Pentaerythritol (Tokyo Chemical Industry Co., Ltd.) Toluene diisocyanate (trade name: Coronate T-80, manufactured by Tosoh Corporation) (hereinafter referred to as TDI) m-Xylylene diisocyanate (product code: D0127, manufactured by Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as XDI) 1,5-Naphthalene diisocyanate (product code: N0168, manufactured by Tokyo Chemical Industry Co., Ltd.) (hereinafter referred to as NDI) Triphenylmethane-4,4',4"-triisocyanate (trade name: Ultite Super CA, manufactured by Toho Chemical Industry Co., Ltd.) (hereafter referred to as TTI), a polyfunctional isocyanate with three or more functional groups. Tris(phenylisocyanate)thiophosphate (trade name: Ultite Super CAII, manufactured by Toho Chemical Industry Co., Ltd.), a tri- or higher functional isocyanate (hereinafter referred to as TPTI) The evaluation results of Examples 1 to 48 and Comparative Examples 1 to 6 are shown in Tables 4 and 5.

[0065] [Table 4]

[0066] [Table 5] [Explanation of symbols]

[0067] 1: blade support portion, 2: neck, 3: lip portion, 4: tapered portion, 5: first taper 1: surface, 6: second tapered surface, 7: tip surface, 8: first edge, 9: second edge, 10: cleaning object, 11: first line segment

Claims

1. a blade support; Neck and a lip portion pivotally connected to the blade support portion via the neck, A wiper blade for a vehicle, which cleans the surface of a member to be cleaned by bringing a part of the lip portion into contact with the surface of the member to be cleaned, The lip portion contains polyurethane, The polyurethane is an isocyanate compound including a diisocyanate and a tri- or higher functional isocyanate; Alcohols including trifunctional or higher polyfunctional alcohols, low molecular weight diols and polyols, and catalyst a composition comprising reactants comprising The polyurethane is heated to 1000°C at a heating rate of 10°C / s using a direct sample introduction mass spectrometer in which the sample is heated and vaporized in an ionization chamber and the sample molecules are ionized. The detected amount of all ions is M1, 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 defined as M2, When the integrated intensity of the peak in the extracted ion thermogram corresponding to the range of m / z values ​​derived from diisocyanate is M3, M2 / M1 is 0.001 to 0.028, M3 / M1 is 0.020 to 0.110, M2 / M3 is 0.013 to 0.300, the concentration of the tri- or higher functional alcohol in the polyurethane is 0.12 mmol / g to 0.65 mmol / g; the diisocyanate is at least one selected from the group consisting of 4,4'-diphenylmethane diisocyanate, toluene diisocyanate, m-xylylene diisocyanate, and 1,5-naphthalene diisocyanate; the tri- or higher functional isocyanate is at least one selected from the group consisting of polymeric MDI, triphenylmethane-4,4',4"-triisocyanate, and tris(phenylisocyanate)thiophosphate; the trifunctional or higher polyfunctional alcohol is at least one selected from the group consisting of trimethylolpropane, glycerin, and pentaerythritol; the low molecular weight diol is 1,4-butanediol; the polyol is at least one selected from the group consisting of polybutylene adipate polyester polyol, polyhexylene adipate polyester polyol, and polytetramethylene ether glycol; The catalyst is N,N'-dimethylhexanolamine.

2. the M2 / M1 is 0.001 to 0.015, the M3 / M1 is 0.040 to 0.100, the M2 / M3 is 0.013 to 0.150, 2. The vehicle wiper blade according to claim 1, wherein the concentration of the tri- or higher functional alcohol in the polyurethane is 0.22 mmol / g to 0.39 mmol / g.

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