JP2002087217A - Wiper blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a wiper blade by integral molding and the wiper blade obtained by the manufacturing method and satisfying desired characteristics such as wiping-off performance, restraint of generation of a chattering sound and durability. SOLUTION: This wiper blade is an integral mold of body and reinforcing materials composed of a thermoplastic elastomer composition, and is set not more than 1×10-3 in a curving factor K determined by an expression (i) when substantially regarding the wiper blade as a two-layer structure of a body layer and a reinforcing material layer when (1) deflection when applying a concentrated load of 50 g to one end of the wiper blade having the length of 200 mm is 20 to 80 mm, (2) Young's moduli of the body material and the reinforcing material are respectively E1 and E2 and a difference in a shrinkage factor between the respective layer materials is δr. The integral molding is desirably performed by co-extrusion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an integrally formed wiper blade and a wiper blade having desired characteristics obtained by the method.

[0002]

2. Description of the Related Art Vehicles such as automobiles and trains, aircraft, ships, and the like have surfaces such as windshields and rear glasses (hereinafter referred to as "surfaces").
Simply called "glass surface". Wipes are installed to wipe out and remove rainwater, muddy water, seawater, ice, snow, dust, etc. attached to the) to improve visibility and ensure driving safety. The wiper blade, which makes contact with the glass surface of the wiper, has a wiping performance on the glass surface, durability such as no abrasion or cracking, and a chattering sound (stick-slip) when friction occurs between the glass and the wiper blade. In addition to what does not occur, some degree of rigidity is required.

For this reason, the wiper blade usually has a composite structure in which a rubber material is used as a main body and a reinforcing material made of metal or resin is incorporated therein. As this rubber material, generally, natural rubber, ethylene-propylene-
Diene rubber (EPDM), chloroprene rubber (CR),
Synthetic rubber such as acrylonitrile-butadiene rubber (NBR), polyester-based thermoplastic elastomer (TP
E) is used. For these rubber materials, a high molecular weight vulcanizate is used in order to secure desired characteristics of the wiper blade, such as wiping performance, durability and suppression of chattering noise. Further, in order to enhance the long-term durability and the effect of suppressing chattering noise, it has been proposed to cure the rubber surface by halogenation.

Generally, such a wiper blade as described above generally forms a main body portion made of a vulcanized material of the rubber material in advance by press molding, and then places a steel plate as a reinforcing material in a slit provided in the main body. Manufactured by inserting.
Therefore, the conventional method of manufacturing a wiper blade requires an assembly process of a main body portion and a reinforcing material, and simplification of the manufacturing process is desired. However, the high-molecular-weight vulcanized rubber material has no fluidity, and is difficult to use with a rubber material. It is difficult to integrally mold the reinforcing material with the extrusion.

It has also been proposed that a resin or a thermoplastic elastomer composition is injection-molded using a reinforcing material as a core material to integrally mold a wiper blade (Japanese Patent Application Laid-Open No. 9-39743).
However, the resin or thermoplastic elastomer composition used for injection molding is hard, and the wiper blade obtained by injection molding is inferior in wiping performance and inferior in long-term durability. Therefore, there is a need for a method of manufacturing a wiper blade by a simplified process, in particular, by integral molding, and at the same time, the emergence of a wiper blade having desired characteristics obtained thereby.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has been made in consideration of the above-described circumstances. It is an object of the present invention to provide a wiper blade satisfying desired characteristics.

[0007]

The inventor of the present invention has studied to obtain a wiper blade having desired characteristics by integral molding. If the thermoplastic elastomer composition and the reinforcing material are mainly extruded, the desired rigidity is secured. Although it is possible to do, it turned out that warpage was easy to occur. Warpage, which occurs in either direction, reduces wiping properties. In particular, when the study of integral molding that does not cause warpage was advanced, the curvature coefficient obtained from the Young's modulus and the shrinkage rate can be used as a guide, and if the curvature coefficient is set to a specific value or less, the thermoplastic elastomer composition and the reinforcement can be used. It has been found that a molded article without warpage can be produced from the material. Further, if the thermoplastic elastomer composition and the reinforcing material are used in combination so that the curvature coefficient is a specific value and the wiper blade has a predetermined rigidity, the desired properties of the wiper blade, particularly the warpage, It has been found that a wiper blade having a desired wiping property can be obtained by integral molding without causing any problem, and the above object can be achieved, thereby completing the present invention. The curvature coefficient is a parameter proposed in a composite between metals, that is, a bimetal technology. In addition, the rigidity of the wiper blade can be based on the deflection.

That is, the wiper blade according to the present invention comprises:
An integral molded body of a main body made of a thermoplastic elastomer composition and a reinforcing material, and satisfies the following properties (1) and (2). (1) the thermoplastic elastomer composition and the Young's modulus of the reinforcing member, respectively E ₁ and E _2, the difference in shrinkage rate of each material and [delta] _r, and the reinforcing material layer substantially body layer the wiper blade and When considered as a two-layer structure, the following formula (i)
Is not more than 1 × 10 ⁻³ , and K = 2δ _r / [3 + {(1 + mn) (1 + mn ³ ) / mn (1 + n) ² }} (where δ _r : Difference in shrinkage between main body material and reinforcing material m = E ₁ / E ₂ (where E ₁ : Young's modulus of main body material, E
₂ : Young's modulus of the reinforcing material) n = h ₁ / h ₂ (where h ₁ : thickness [mm] of the body material,
h _2: Thickness of the reinforcing material [mm]) (2) 200mm deflection when applying a concentrated load of 50g to one end of the length wiper blade is 20 to 80 mm.

The thermoplastic elastomer composition comprises a thermoplastic resin and a dynamically crosslinked elastomer component,
It is desirable that the elastomer component has a structure in which the dynamically crosslinked elastomer component is dispersed in a continuous phase made of a thermoplastic resin. The wiper blade is generally used in the above (1) and (2)
It is desirable that the thermoplastic elastomer composition selected so as to satisfy the above condition and the reinforcing material be integrally molded by coextrusion.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 schematically shows a cross-sectional view of the wiper blade.
In the figure, the bottom surface side is the glass contact surface side. The wiper blade of the present invention is an integrally formed body of the main body made of the thermoplastic elastomer composition 1 and the reinforcing material 2, and satisfies the following properties (1) and (2). (1) the thermoplastic elastomer composition and the Young's modulus of the reinforcing member, respectively E ₁ and E _2, the difference in shrinkage rate of each material and [delta] _r, and substantially the body first layer and the reinforcing member 2 the wiper blade When considered as a two-layer structure with layers (FIG. 2), the curvature coefficient K obtained by the following equation (i) is 1 × 10 ⁻³ or less.

K = 2δ _r / [3 + {(1 + mn) (1 + mn ³ ) / mn (1 + n) ² }] (where, δ _{r is} the difference in shrinkage between the main body material and the reinforcing material m = E ₁ / E ₂ (where E ₁ : Young's modulus of body material, E
₂ : Young's modulus of the reinforcing material) n = h ₁ / h ₂ (where h ₁ : thickness [mm] of the body material,
h _2: height of the reinforcing material thickness [mm]) Note thermoplastic elastomer composition represented by h ₁ in FIG. 2, in FIG. 1, corresponding to t-h _2.

The curvature coefficient K obtained by the equation (i) is a measure of the warpage of the wiper blade in the longitudinal direction. This will be described specifically. In a composite material composed of the thermoplastic elastomer composition 1 and the reinforcing material 2 as schematically shown in FIG. 2, the shrinkage ratios of the materials are usually different, and the thermoplastic elastomer composition 1 becomes a relatively high shrinkage material, Reinforcement 2
Is a relatively low shrinkage material. A composite material composed of such a high-shrink material and a low-shrink material is obtained by applying a bending coefficient K proposed for bimetal (“About bimetal and thermostat” disclosed on the Internet, Fuji Metal Co., Ltd .: Fujimoto), It can be considered as follows. This will be described with reference to FIGS.

During molding, stresses P ₁ and P ₂ are generated due to shrinkage. P _{1 =} P ₂ = P ... if (1) high shrinkage material and the low shrinkage material bending moment and M _1, M ₂ each _{M 1 = (h 1/2} ) P 1 ... (2) M 2 = ( when the _{h 2/2) P 2 ...} (3) where all layer thickness _{t = h 1 + h 2,} M 1 + M 2 = (P 1 h 1/2) + (P 2 h 2/2) = P (H ₁ + h ₂ ) / 2 = Pt / 2 (4)

Assuming that a wiper blade having a length 1 as shown in FIG. 4 is curved with a radius of curvature r after contraction, and when the moment of inertia is I, from 1 / r = M / EI, M = EI / r Yes,
Therefore, M ₁ = E ₁ I ₁ / r,... (5) M ₂ = E ₂ I ₂ / r,... (6) Equation (4) is represented by equation (7). M ₁ + M ₂ = Pt / 2 = (E ₁ I ₁ + E ₂ I ₂ ) / r (7)

Further, since the unit elongation at the interface is equal, ρ ₁ + P ₁ / E ₁ + h ₁ / 2r = ρ ₂ −P ₂ / E ₂ h ₂ −h ₂ / 2r (8) _{/ r = (ρ 2 -ρ 1} ) / (t / 2 +2 (E 1 I 1 + E 2 I 2) (1 / E 1 h 1 + 1 / E 2 h 2) / t) ... (9) (9 the moment of inertia I in) taken at unit ^{_{width, I 1 = h 1 3 /}} l 1, if ^{_{I 2 = h 2 3 / l}} 2, l / r = 6 (ρ 2 -ρ 1) (h 1 _{+ h 2) h 1 h 2} E 1 E 2/3 (h 1 + h 2) 2 h 1 h 2 E 1 E 2 + (h 1 E 1 + h 2 E 2) (h 1 3 E 1 + h 2 ³ E ₂ )] ... (10) If the longitudinal elastic modulus ratio m = E ₁ / E ₂ and the plate pressure ratio n = h ₁ / h _{2 in} equation (10), l / r = 6 (ρ ₂ −ρ ₁ ) (1 + n ² ) / t [3 (1 + n ² ) + (1 + mn) (n ² + 1 / mn)]… (11) where 3 (ρ ₂ -ρ ₁ ) (1+ If n ² ) / [3 (1 + n ² ) + (1 + mn) (n ² + 1 / mn)] = K, then K = 3Δρ / [3+ (1 + mn) (1 + n ³ m ) / Mn (1 + n) ² ] (12) Equation (11) is expressed as l / r = 2 K / t (13)

In FIG. 4, assuming that the amount of warpage is D, D = l ² / 8r (14) Substituting equation (14) into equation (13), D = Kl ² / 4t (15) From 15), the curvature coefficient K can be used as a guide for the amount of warpage D.

In the above, the formula (i) has been described for the blade having the cross-sectional shape shown in FIG. 1. However, the present invention can be applied to a case in which the cross-section of the reinforcing material has a cross-sectional shape that can be approximated to the square shape schematically shown in FIG. it can. The cross section of the reinforcing material is, for example, foil, plate,
It may be square, elliptical, corrugated, etc., such as a box. Further, a blade including a plurality of reinforcing members may be used. 5 (a) to 5 (m) show several examples of cross sections of the shape of the reinforcing material applicable to the present invention.

(2) The wiper blade of the present invention is 200 m
The deflection when a concentrated load of 50 g is applied to one end of the m-length wiper blade is 20 to 80 mm, preferably 30 to 60 mm.
mm.

In the present invention, the above characteristics are satisfied,
The thermoplastic elastomer composition and the reinforcing material of the main body are not particularly limited as long as they can be integrally molded. However, in consideration of characteristics desired for the wiper blade, the main body is dynamically crosslinked with a thermoplastic resin (hereinafter, also referred to as a resin component). It is desirable that the dynamically crosslinked elastomer component comprises a thermoplastic elastomer composition having a structure dispersed in a continuous phase composed of a resin component.

As the resin component, known thermoplastic resins which can be thermoformed can be widely used. For example, polyolefin resins (eg, high-density polyethylene (HDP)
E), low density polyethylene (LDPE), ultra high molecular weight polyethylene (UHMWPE), polypropylene (PP) such as isotactic polypropylene, syndiotactic polypropylene, ethylene propylene copolymer resin), polyamide resin (for example, nylon 6 ( N6),
Nylon 66 (N66), Nylon 46 (N46), Nylon 11 (N11), Nylon 12 (N12), Nylon 610 (N610), Nylon 612 (N61)
2), nylon 6/66 copolymer (N6 / 66), nylon 6/66/610 copolymer (N6 / 66/61)
0), nylon MXD6 (MXD6), nylon 6T,
Nylon 6 / 6T copolymer, Nylon 66 / PP copolymer, Nylon 66 / PPS copolymer), polyester resin (for example, polybutylene terephthalate (PBT),
Polyethylene terephthalate (PET), polyethylene isophthalate (PEI), polyester copolymer, P
ET / PEI copolymer, polyarylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, aromatic polyester such as polyoxyalkylenediimidic acid / polybutylate terephthalate copolymer),
Polyether resin (for example, polyacetal (PO
M), polyphenylene oxide (PPO), polysulfone (PSF), polyetheretherketone (PEE)
K)), polynitrile resins (eg, polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile / styrene copolymer (AS), methacrylonitrile / styrene copolymer, methacrylonitrile / styrene / butadiene copolymer) , Polymethacrylate resins (eg, polymethyl methacrylate (PMMA), polyethyl methacrylate), polyvinyl resins (eg, vinyl acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol / ethylene copolymer (EVOH), Vinylidene chloride (PVDC), polyvinyl chloride (PV
C), vinyl chloride / vinylidene chloride copolymer, vinylidene chloride / methyl acrylate copolymer), cellulosic resins (eg, cellulose acetate, cellulose acetate butyrate),
Fluorinated resin (for example, polyvinylidene fluoride (PVD)
F), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene /
Ethylene copolymer (ETFE), imide-based resin (eg, aromatic polyimide (PI)), polyacetal, and the like can be used.

As a resin component, a so-called thermoplastic elastomer (TP) comprising a hard segment composed of a crystalline thermoplastic resin and an amorphous soft segment.
E) can also be used. Specific examples include TPEs such as polyurethane-based elastomers, polyester-based elastomers, fluoropolymer-based elastomers, and polyamide-based elastomers.

More specifically, polyurethane elastomers include those having short-chain glycol diisocyanate as a hard segment and long-chain polyol as a soft segment, and a hard segment rich in urethane and urea bonds and a polyether. And a soft segment. Examples of the polyester-based elastomer include those having polybutylene terephthalate as a hard segment and long-chain polyol or polyester as a soft segment. Examples of the fluoropolymer-based elastomer include those having a fluororesin component as a hard segment and a fluororubber component as a soft segment. Examples of the polyamide-based elastomer include those having nylon as a hard segment and polytetramethylene glycol as a soft segment.

Among the above, considering cost, friction coefficient, melting point, etc., polypropylene (PP), polyamide resin, polyester resin, polyether resin, fluorine resin, polyamide elastomer, polyurethane elastomer, polyester elastomer Elastomer (COP
E) and the like are preferably used. These may be used alone or as a combination of two or more resin components.

In particular, among the above resin components, those having a melting point of 200 ° C. or more are preferably used. As will be described later, in the present invention, in the wiper blade main body after molding, the resin component usually forms a continuous phase, that is, the blade surface substantially consists of the resin component. When using the wiper blade, there is a case where the glass surface is continuously wiped with no water on the glass surface, for example, in snow or in a tunnel. At this time, if the material of the wiper blade has a low melting point, the frictional heat generated between the wiper blade and the glass causes melting at the contact surface with the glass surface, and the wiper blade adheres to the glass surface, resulting in poor sliding. . Even in the case where the dried glass surface is continuously wiped for a long time as long as the surface of the wiper blade has a melting point of 200 ° C. or more, the glass surface is not melted by frictional heat.

Further, as the elastomer component, for example, the following elastomers and these or any mixture containing these can be used. Diene rubbers and hydrogenated products thereof (for example, NR, IR, epoxidized natural rubber, SBR, BR (high cis BR and low cis B)
R), NBR, hydrogenated NBR, hydrogenated SBR), olefin-based rubber (for example, ethylene-propylene-diene rubber (EPDM), ethylene propylene rubber such as EPM), maleic acid-modified ethylene propylene rubber (ME)
PM), IIR, isobutylene and aromatic vinyl or diene monomer copolymer, acrylic rubber (ACM), ionomer), halogen-containing rubber (for example, Br-II)
R, CI-IIR, bromide of isobutylene paramethylstyrene copolymer (Br-IPMS), CR, hydrin rubber (CHR), chlorosulfonated polyethylene (CS
M), chlorinated polyethylene (CM), maleic acid-modified chlorinated polyethylene (M-CM), silicone rubber (for example, methyl vinyl silicone rubber, dimethyl silicone rubber,
Methylphenylvinyl silicone rubber), sulfur-containing rubber (for example, polysulfide rubber), fluorine rubber (for example, vinylidene fluoride rubber, fluorine-containing vinyl ether rubber, tetrafluoroethylene-propylene rubber, fluorine-containing silicon rubber, fluorine-containing phosphazene rubber ), Urethane rubber, epichlorohydrin rubber, thermoplastic elastomers (for example, styrene-based elastomers,
Olefin elastomer, ester elastomer,
Urethane-based elastomer, polyamide-based elastomer)
And the like.

Among these, olefin rubbers such as acrylic rubber (ACM) and ethylene-propylene-diene rubber (EPDM), diene rubbers or hydrogenated products thereof, in consideration of cost, weather resistance, chemical resistance, etc. Halogen-containing rubber, fluorine rubber, urethane rubber, and epichlorohydrin rubber are preferably used. These may be used alone or in combination of two or more. When forming the thermoplastic elastomer composition, the resin component and the elastomer component as described above may be selected so as to satisfy the values of (1) the rigidity and (2) the curvature coefficient.

It is known that in order to eliminate the chatter of the wiper, it is necessary to lower the friction coefficient of the blade material. Generally, a thermoplastic resin has a small friction coefficient. For example, the dynamic friction coefficient is 0.39 for nylon 6, 0.23 for high-density polyethylene, and 0.56 for polypropylene. In contrast, elastomers have a high coefficient of kinetic friction, especially about 2 to 3 for vulcanized rubber. Therefore, it is obvious that a thermoplastic resin with a small coefficient of friction should be used,
If the thermoplastic resin is used as it is as the wiper blade, it is too hard to follow the curved surface of the windshield of an automobile, and the wiping performance is extremely poor. On the other hand, when this thermoplastic resin is used as a continuous phase (matrix) and a thermoplastic elastomer composition having a structure in which an elastomer component (vulcanized) is dispersed is used as a body material of a wiper blade, the glass contact surface is Since it is substantially a thermoplastic resin, the coefficient of friction is small, and chatter is unlikely to occur. In addition, the wiper blade as a whole is sufficiently softened by the elastomer of the dispersion layer, so that the wiper blade can sufficiently follow glass having a curved surface.

The ratio of the resin component to the elastomer component is not particularly limited. However, in order to form a thermoplastic elastomer composition having the above structure, the thermoplastic resin / elastomer component (weight ratio) is usually 85%. / 15-15 /
It is desirably 85. The amount of the elastomer component here is an amount limited to form a dispersed structure of the thermoplastic elastomer composition, and therefore, is generally blended with the elastomer together with the elastomer (main material) exemplified above. It means an amount containing other components.

Even if the two components are simply kneaded in a molten state at such a ratio, a thermoplastic elastomer composition having the above-mentioned phase-dispersed structure is not necessarily obtained. It is desirable to consider
In particular, it is desirable to select an intrinsic melt viscosity at the time of kneading the resin component and the elastomer component. Specifically, it is selected such that the α value obtained as follows becomes smaller than 1. As long as the α value does not exceed 1, any ratio may be used. When the α value is smaller than 1, the elastomer component is a dispersed phase (island), and the thermoplastic resin can have a sea-island dispersed structure of a matrix (sea). With such a sea-island dispersed structure, the thermoplastic resin constituting the matrix flows at the time of melting, and the same molding as the thermoplastic resin can be performed.

Α = (φ _R / φ _P ) × (η _P / η _R ) (where, φ _R : volume fraction of elastomer component φ _P : volume fraction of resin component η _R : temperature and temperature during kneading Melt viscosity of elastomer component under shear rate condition η _P : Melt viscosity of resin component under temperature during kneading and shear rate condition) When the above α value is 1 or more, the thermoplastic elastomer composition becomes a matrix in which the elastomer component becomes a matrix. If the vulcanizing agent is further added to the thermoplastic elastomer composition, the thermoplastic elastomer composition becomes granular and loses the fluidity, making molding difficult.

The above-mentioned melt viscosity η refers to the melt viscosity of an arbitrary temperature and component during kneading, and the melt viscosity of each material depends on the temperature, shear rate (sec ⁻¹ ) and shear stress. In general, it can be determined by the following formula (ii) from the stress and shear rate of the polymer material measured in an arbitrary temperature in a molten state flowing through the thin tube, particularly in a temperature region during kneading. At the time of measuring the melt viscosity, a capillary rheometer (Capillograph 1C: manufactured by Toyo Seiki Co., Ltd.) can be used.

[0032]

(Equation 1)

The thermoplastic elastomer composition may contain optional components, if necessary, in addition to the above-mentioned resin component and elastomer component as long as the object of the present invention is not impaired. Generally, it is desirable that the thermoplastic elastomer composition contains a vulcanizing agent for the elastomer component.

The vulcanization system may be appropriately determined according to the elastomer component used, including vulcanization conditions (temperature and time), and is not particularly limited. The vulcanizing system may use a vulcanizing agent, a general vulcanizing agent (crosslinking agent), which may be used alone or in combination of two or more of the following vulcanizing agents and vulcanizing aids. it can. Specifically, examples of the sulfur-based vulcanizing agent include powdered sulfur, precipitated sulfur, highly dispersible sulfur, surface-treated sulfur, insoluble sulfur, dimorpholine disulfide, and alkylphenol disulfide, for example, 0.5 to 4 phr. (Parts by weight per 100 parts by weight of the elastomer component (polymer)) can be used.

The organic peroxide vulcanizing agents include benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide,
Examples thereof include 2,5-dimethyl-2,5-di (t-butylperoxy) hexane and 2,5-dimethylhexane-2,5-di (peroxylbenzoate). Good. Further, examples of the phenol resin-based vulcanizing agent include brominated alkylphenol resins and mixed cross-linking systems containing a halogen donor such as tin chloride and chloroprene and an alkylphenol resin. For example, about 1 to 20 phr may be used. it can.

Zinc white (about 5 phr), magnesium oxide (about 4 phr), litharge (about 10 to 20 phr), p-quinone dioxime, p-dibenzoylquinone dioxime, tetrachloro-p-benzoquinone, poly-
p-Dinitrosobenzene (about 2 to 10 phr), methylin dianiline (about 0.2 to 10 phr) and the like can also be used.

[0037] If necessary, a vulcanization accelerator may be added. As vulcanization accelerators, aldehyde / ammonia,
General vulcanization accelerators such as guanidine, thiazole, sulfenamide, thiuram, dithioate, and thiourea can be used, for example, about 0.5 to 2 phr.

Specifically, the aldehyde / ammonia vulcanization accelerator includes hexamethylenetetramine and the like; the guanidine vulcanization accelerator includes diphenylguanidine and the like; and the thiazole vulcanization accelerator includes dibenzothia vulcanization accelerator. Zirdisulphide (DM), 2-mercaptobenzothiazole and its Zn salt, cyclohexylamine salt, and the like; sulfenamide vulcanization accelerators include cyclohexylbenzothiazylsulfenamide (CBS);
N-oxydiethylenebenzothiazyl-2-sulfenamide, Nt-butyl-2-benzothiazolesulfenamide, 2- (thymolpolynyldithio) benzothiazole and the like; , Tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthiuram monosulfide (TMTM), dipentamethylenethiuram tetrasulfide, etc .; as dithioate vulcanization accelerators, Zn-dimethyldithiocarbamate; Zn-
Thiourea such as diethyldithiocarbamate, Zn-di-n-butyldithiocarbamate, Zn-ethylphenyldithiocarbamate, Tc-diethyldithiocarbamate, Cu-dimethyldithiocarbamate, Fe-dimethyldithiocarbamate, pipecoline pipecolyldithiocarbamate; Examples of the system vulcanization accelerator include ethylene thiourea and diethyl thiourea;
In addition, as a vulcanization accelerator, general rubber auxiliaries can be used in combination, and examples thereof include zinc white (about 5 phr), stearic acid and oleic acid, and Zn salts thereof (about 2 to 4 phr). Can be used.

[0039] The thermoplastic elastomer composition may also contain a sliding agent. The sliding agent is not particularly limited, but a surfactant such as an organosiloxane; a sliding material such as ethylene tetrafluoride powder, molybdenum disulfide, graphite, spheroidal graphite, short fiber, and ultrafine fiber is preferably used. The content of the sliding agent is the thermoplastic elastomer composition 1
When the amount is about 0.05 to 100 parts by weight with respect to 00 parts by weight, a sufficient sliding effect is obtained, and a bending resistance effect and the like can be obtained.

When the chemical compatibility between the resin component and the elastomer component is different, it is preferable to use a suitable compatibilizer as the third component to compatibilize them. By adding the compatibilizer, the interfacial tension between the thermoplastic resin composition and the elastomer composition decreases, and as a result, the particle diameter of the elastomer component forming the dispersion layer becomes fine, so that the properties of both components are reduced. Is more effectively expressed.
Such a compatibilizer is generally a resin component, a copolymer having a structure of both or one of the elastomer component,
Alternatively, the copolymer may have a structure of a copolymer having an epoxy group, a carboxyl group, a carbonyl group, a halogen group, an amino group, an oxazoline group, a hydroxyl group, etc., which can react with the resin component or the elastomer component. These may be selected depending on the types of the resin component and the elastomer component to be mixed, and those usually used include styrene-ethylene-butylene-styrene block copolymer (SE).
BS) and its modified maleic acid, EPDM, EPM
And maleic acid-modified products thereof, EPDM / styrene or EPDM / acrylonitrile graft copolymers and their maleic acid-modified products, styrene / maleic acid copolymers, and reactive phenoxines. The amount of the compatibilizer is not particularly limited, but is preferably a polymer component (the sum of a thermoplastic resin and an elastomer).
0.5 to 20 parts by weight per 100 parts by weight is preferred.

In order to improve the fluidity, heat resistance, physical strength, cost and the like of the thermoplastic elastomer composition, reinforcing agents, fillers,
A necessary amount of a compounding agent, such as a softening agent, an antioxidant, or a processing aid, which is added to a usual composition, can also be added. Further, a pigment can be added for the purpose of coloring or the like.

As the pigment, an inorganic pigment and an organic pigment can be used. Inorganic pigments include, for example, zinc white, titanium oxide, red iron oxide, chromium oxide, iron black, and composite oxides (eg, titanium yellow, zinc-iron brown, titanium / cobalt green, cobalt green, cobalt blue, copper-chromium) Oxides such as black, copper-iron black); chromates such as graphite and molybdate orange; ferrocyanides such as navy blue; sulfides such as cadmium yellow, cadmium red and zinc sulfide; sulfuric acids such as barium sulfate Salt; silicates such as ultramarine blue; carbonates such as calcium carbonate; phosphates such as manganese violet; hydroxides such as yellow iron oxide; carbon such as carbon black; metal powders such as aluminum powder and bronze powder; Is mentioned. Organic pigments include monoazo lakes (for example, Lake Red C,
Permanen Red 2B, Brilliant Carmine 6B),
Monoazo type (for example, toluidine red, naphthol red, fast ero G, benzimidalone bordeaux,
Azo system such as benzimidazolone brown), disazo system (for example, disazo yellow AAA, disazo yellow HR, pyrazolone red), condensed azo system (for example, condensed azo yellow, condensed azo red, condensed azo brown), metal complex salt azo system (for example, nickel azo yellow) Pigments; phthalocyanine-based pigments such as copper phthalocyanine blue, copper phthalocyanine green, and brominated copper phthalocyanine green; basic dye lakes (for example, rhodamine 6 lake)
Dyes such as anthraquinones (eg, flavanthrone yellow, dianthraquinolyl red, indanthrene blue), thioindigos (eg, thioindigo bordeaux), perinones (eg, perinone orange),
Perylene (eg, perylene scarlet, perylene red, perylene maroon), quinacridone (eg, quinacridone red, quinacridone magenta, quinacridone scarlet), dioxazine (eg, dioxazine violet), isoindolinone (eg, isoindolinone yellow), quinophthalone Condensed polycyclic pigments such as azoline (eg, quinophthalone yellow), isoindoline (eg, isoindoline yellow), and pyrrole (eg, pyrrole red); metal complex salts azomethine such as copper azomethine yellow; aniline black; .

The dynamic vulcanization of the elastomer component may be carried out by kneading the elastomer component in the presence of a vulcanizing agent. Therefore, the elastomer component containing the vulcanizing agent is kneaded in advance and dynamically vulcanized. Kneading may be carried out, or a vulcanizing agent may be added at the time of kneading the resin component and the unvulcanized elastomer component. In order to prepare a thermoplastic elastomer composition having a structure in which a dynamically vulcanized elastomer component (domain) is dispersed in a continuous phase (matrix phase) of a resin component from a resin component and an elastomer component, the latter is preferable. That is, an unvulcanized elastomer component and a resin component are
It is desirable to melt-knead with a shaft kneading extruder or the like and then dynamically vulcanize the elastomer component.

The optional components may be added during kneading, but it is preferable that the optional components are previously contained in the resin component or the elastomer component before kneading. For kneading the resin component and the elastomer component, a general kneader can be widely used, and a screw extruder, a kneader, a Banbury mixer, a twin-screw kneading extruder and the like can be used. In particular, when performing dynamic vulcanization of the elastomer component at the time of kneading the resin component and the elastomer component, it is preferable to use a twin-screw kneading extruder. Further, two or more kinds of kneaders may be used and kneading may be sequentially performed. The melting and kneading temperature is preferably equal to or higher than the temperature at which the thermoplastic resin melts. The shear rate during kneading is 500
~ 7500 sec ^-1 is preferred. The entire kneading time is usually about 30 seconds to 10 minutes, and the vulcanization time after adding the vulcanizing agent is
Usually, it is about 15 seconds to 5 minutes.

The hardness of the thermoplastic elastomer composition as described above is preferably 50 to 80 in JIS A hardness. When the JIS A hardness of the main body is 50 or more, when the glass is wiped, the wiper blade does not fall down too much to prevent a turn. Further, when the JIS A hardness of the main body is 80 or less, the wiper blade adheres to the glass surface, and the wiping performance becomes particularly excellent.

In the wiper blade of the present invention, as described above, the thermoplastic elastomer composition having a resin component as a continuous phase is formed by integrally molding the thermoplastic elastomer composition with a reinforcing material, and the thermoplastic elastomer composition is brought into contact with glass. In this case, the resin component becomes a contact surface with the glass. Since the resin component has a small coefficient of friction and excellent abrasion resistance, chatter noise of the wiper blade is suppressed, and excellent durability is obtained.

The wiper blade of the present invention uses the above-mentioned thermoplastic elastomer composition as a main body material and is integrally formed with a reinforcing material. As the reinforcing material, for example, metal, glass fiber, carbon fiber, resin, FRP (fiber reinforced plastic), and a composite material thereof can be used. The metal is not particularly limited. For example, iron, aluminum, copper, stainless steel, and metals
Or more alloys. Among metals, stainless steel is preferable because of its rigidity and corrosiveness. As the reinforcing material, any of the thermoplastic resins and the thermosetting resins exemplified as the resin component contained in the thermoplastic elastomer composition can be used. In particular, it is preferable to use the thermoplastic resin because the reinforcing material and the wiper blade main body are firmly adhered to each other, so that the durability of the wiper blade is improved. It is also possible to increase the rigidity of the reinforcing material by mixing glass fibers or carbon fibers in the thermoplastic resin. Examples of the thermosetting resin include a phenol resin, a urea resin, a melamine resin, an epoxy resin, and a silicon resin.

The reinforcing material imparts rigidity to the wiper blade, and the wiper blade produced by integral molding only has to satisfy the desired rigidity (1) and the curvature coefficient (2) of the wiper blade. The shape, number, position, material and the like are not particularly limited. In the present invention,
For the sake of convenience, the shape of the reinforcing member has been described with reference to the rectangular cross section shown in FIG. 1 or FIG. 6, but the shape is similar to FIG. 2 and is not particularly limited as long as a desired curvature coefficient is obtained. The reinforcing material is 2
The above may be incorporated. Further, the reinforcing material may extend over the entire length of the wiper blade or may not extend to both ends of the wiper blade. The cross-sectional shape of the reinforcing material may be uniform in the length direction of the wiper blade, or may differ depending on the position in the length direction. Further, the reinforcing material is not limited to the one incorporated therein, and a part of the reinforcing material may be exposed to the outside of the wiper blade as shown in FIG. 6 (c).

In the present invention, it is desirable to manufacture a wiper blade by co-extrusion of the reinforcing material and the thermoplastic elastomer composition. A method in which the same shape is formed into an infinite length, and a required length is cut therefrom and used as a wiper blade has the highest working efficiency. For example, when the reinforcing material is a metal, the reinforcing material may be previously wound into a roll, and then may be formed by passing through a die of an extruder so that the thermoplastic elastomer composition covers around the reinforcing material. When is a resin, using two extruders, the thermoplastic elastomer composition and the reinforcing material may be simultaneously co-extruded and integrally molded, or while forming the resin reinforcing material in a tandem system, A thermoplastic elastomer composition may be coated thereon. In the present invention, if the thermoplastic elastomer and the reinforcing material are used, the reinforcing material may be inserted into a mold in advance by an injection molding method, and a wiper blade may be formed by injection molding the thermoplastic elastomer composition. it can.

[0050]

EXAMPLES Next, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. Example 1 <Preparation of Thermoplastic Elastomer Composition> Each component having the composition (weight ratio) shown in Table 1 was charged into a Banbury mixer, and was mixed for about 3 times.
After kneading for 120 minutes, the mixture was discharged at 120 ° C. and pelletized with a rubber pelletizer.

[0051]

The pellets of the elastomer compound obtained above were dry-blended with the components shown in Table 2,
The mixture was charged into a twin-screw kneader set at 180 ° C. at the front and 220 ° C. at the rear, kneaded at a shear rate of 1000 sec ⁻¹ , and when sufficiently kneaded, a vulcanization system was added to obtain a thermoplastic elastomer composition. The molding conditions at this time (22
At 0 ° C. and a shear rate of 1000 sec ⁻¹ ), the melt viscosity of each component was measured with a capillary rheometer, and the α value was calculated. Among them, the thermoplastic elastomers 3 and 4 had too large proportion of the elastomer (α ≧ 1), and the sea-island structure was reversed, so that kneading was not possible, and samples could not be obtained.

[0053]

[Table 1] In the table, COPE: polyester-based thermoplastic elastomer (Perprene P95C, manufactured by Toyobo Co., Ltd., JIS A hardness 95, melting point: 213 ° C.) PP: polypropylene (RB121D, manufactured by Tokuyama Corporation)
(Melting point 150 ° C) Vulcanized Zinc flower: Zinc flower No. 3, stearic acid: beads stearic acid, manufactured by Seido Chemical Co., Ltd., Nippon Oil & Fats Co., Ltd. Butanetetracarboxylic acid: BTC; 250-I, manufactured by Taoka Chemical Co., Ltd.

The obtained thermoplastic elastomer composition was
Formed into a 2 mm thick plate, stacking three of them
A hardness (based on JIS K6253) was measured. Table 2
Shown inside.

<Preparation of Wiper Blade> FIG. 1 (FIG. 6)
A wiper blade having the shape shown in (a)) was produced. The thermoplastic elastomer composition obtained above was coextruded with a main body material and a ribbon steel material (reinforcing material) having a cross-sectional shape of 5 mm × 0.7 mm to continuously produce a wiper blade. The obtained thermoplastic elastomer composition was observed with a transmission electron microscope, and it was confirmed that the thermoplastic elastomer composition had a structure in which an elastomer component was dispersed in a continuous phase composed of a resin component. Table 3 shows the warpage (D value shown in FIG. 4) measured by the obtained wiper blade, the warpage obtained by calculation, and the curvature coefficient (calculated value) K value.
Further, with respect to the obtained wiper blade, wiping performance when wiping performance was performed at a length of 475 mm (wiping unevenness)
Are shown in Table 3 when the evaluation was carried out by Nissan Silvia manufactured in 1991. In Table 3, ○ indicates the remaining area of wiping of 1 cm ² or less,
× indicates a remaining area of wiping of 2 cm ² or more.

Comparative Example 1 A wiper blade was prepared in the same manner as in Example 1 except that the reinforcing material was changed to a polyester thermoplastic elastomer (Perprene P95C, manufactured by Toyobo Co., Ltd.) having the same shape and dimensions. Produced. Table 3 shows the results.

Comparative Example 2 In Example 1, except that the thickness of the ribbon steel material (FIG. 6B) was reduced to 0.4 mm.
A wiper blade was manufactured in the same manner as in Example 1. Table 3 shows the results.

Example 2 In Example 1, except that the reinforcing material was changed to a thermoplastic resin (Perprene P95C, manufactured by Toyobo Co., Ltd.) having a cross-sectional shape (6 mm × 3.5 mm) shown in FIG. A wiper blade was manufactured in the same manner as in Example 1. Table 3 shows the results.

(Example 3) In Example 2, except that the main body was changed to the thermoplastic elastomer composition 2 in Table 2,
A wiper blade was manufactured in the same manner as in Example 1. Table 3 shows the results.

[0060]

[Table 2]

[0061]

According to the present invention, a wiper blade satisfying desired characteristics such as wiping properties, suppression of chattering noise and durability can be obtained by integral molding, and the wiper blade can be manufactured in a simple process. Provided is a useful wiper blade and method of making the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a wiper blade of the present invention.

FIG. 2 is a schematic cross-sectional view of a wiper blade used for obtaining a curvature coefficient of the wiper blade in the present invention.

FIG. 3 is an explanatory diagram of stress in FIG. 2;

FIG. 4 is an explanatory diagram of warpage.

FIGS. 5A to 5M are cross-sectional views showing examples of the shape of a reinforcing member.

FIGS. 6 (a), (b) and (c) are cross-sectional views of wiper blades manufactured in Examples and Comparative Examples.

[Explanation of symbols]

 1 thermoplastic elastomer composition (body) 2 reinforcing material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masuda Kuroda 2-1 Oiwake, Hiratsuka-shi, Kanagawa Prefecture Yokohama Rubber Co., Ltd. Inside the Hiratsuka Factory (72) Inventor Naoyuki Ooka 2-1 Oiwake, Hiratsuka-shi, Kanagawa Prefecture Yokohama Rubber Co., Ltd. (72) Inventor Noboru Ishida No. 311 Numato, Shimotakayanagi, Kaza-shi, Saitama Japan F-term (reference) 3D025 AA01 AC01 AD01 AE11 AE16 4F072 AA01 AA08 AB09 AB10 AC13 AD01 AD04 AD06 AD07 AD08 AD09 AD37 AD42 AD44 AD45 AD46 AG02 AG12 AG13 AK02 AK16 AL02

Claims (3)

[Claims] An integrated molded article of a main body made of a thermoplastic elastomer composition and a reinforcing material, comprising the following properties (1) and
(2) wiper blade satisfy: (1) the thermoplastic elastomer composition and the Young's modulus of the reinforcing member, respectively E ₁ and E _2, the difference in shrinkage rate of each material and [delta] _r, and substantially the wiper blade Assuming that a two-layer structure composed of the main body layer and the reinforcing material layer, the curvature coefficient K obtained by the following equation (i) is 1 × 10 ⁻³ or less, and K = 2δ _r / [3 + ｛(1 + mn) ) (1 + mn ³ ) / mn (1 + n) ² }] (where δ _{r is} the difference in shrinkage between the body material and the reinforcing material m = E ₁ / E ₂ (where E _{1 is the} body material) Young's modulus, E
₂ : Young's modulus of the reinforcing material) n = h ₁ / h ₂ (where h ₁ : thickness of the body material, h ₂ :
(2) The bending when applying a concentrated load of 50 g to one end of a 200 mm long wiper blade is 20 to 80 mm. 2. The thermoplastic elastomer composition comprises a thermoplastic resin and a dynamically crosslinked elastomer component,
The wiper blade according to claim 1, wherein the dynamically crosslinked elastomer component has a structure dispersed in a continuous phase made of a thermoplastic resin. 3. The production of a wiper blade according to claim 1, wherein the thermoplastic elastomer composition selected to satisfy the above (1) and (2) and the reinforcing material are integrally formed by coextrusion. Method.