Wiping blade comprising a base body and a cross-linked lubricating body

Abstract

TITLE: Wiping blade comprising a crosslinked base body and lubricant body. Method for making a wiping blade (10) in which a first material (11*) is extruded from a base body (11) and a second material (12*) from a lubricated body (12) of the wiping blade (10), the lubricated body (12) covering a portion of the base body (11) intended for wiping contact. The first (11*) and second material (12*) comprise a crosslinkable polymer. The second material (12*) comprises a crosslinking agent for crosslinking a polymer of the second material (12*) and a polymer of the first material (11*). The first material (11*) contains a crosslinking agent for crosslinking a polymer of the first material (11*) and a polymer of the second material (12*). Figure 1

Description

Title of the invention: Wiping blade comprising a cross-linked base body and lubricant body. FIELD OF THE INVENTION

[0001] The present invention relates to a method for producing a wiping blade and to the wiping blade obtained. STATE OF THE ART

[0002] Current wiper blades, for example, for windshield wiper blades, are generally first extruded as a double-profile cord and then vulcanized. To ensure adhesion of a friction-reducing lubricating varnish coating, the double strip is first halogenated or activated by plasma, and then a coating of solvent-containing lubricating varnish is applied by spraying. After the lubricating varnish coating has solidified, for example, by drying and / or hardening, the double-profile cord is cut in the middle.

[0003] Such usual manufacturing processes thus consist of at least five steps (extrusion, vulcanization, halogenation / activation, coating, solidification and cutting).

[0004] Document DE 10 2016 213 862 Al relates to another method of making wiping blades for windshield wiper blades.

[0005] DESCRIPTION AND ADVANTAGES OF THE INVENTION

[0006] The present invention relates to a method for making a wiping blade, in particular for a windshield wiper, according to which

[0007] - a first material is extruded and / or injected and / or molded for a body of base and a second material for at least one lubricated body of the wiping blade in common in the form of a bead base body - lubricated body,

[0008] - the lubricated body covering a portion of the surface of the base body intended for wiper blade contact

[0009] - the first material and the second material, each comprising respectively at minus a crosslinkable polymer,

[0010] - the second material comprising at least one material crosslinking agent, to crosslink at least one crosslinkable polymer of the second material and at least one crosslinkable polymer of the first material, and / or

[0011] - the first material containing at least one material crosslinking agent for crosslink at least one crosslinkable polymer of the first material and at least one crosslinkable polymer of the second material.

[0012] In other words, the present invention relates to a method for manufacturing a wiping blade, particularly for a windshield wiper, for example, for a windshield wiper blade intended for a vehicle. According to this method, a first material is extruded for the base body and a second material for at least one lubricated section of the wiping blade, to obtain a bead (base body-lubricated section), and / or the material is injected and / or molded, and in particular, extruded. The lubricated section covers at least a portion of the surface of the base body, which is intended for the wiping contact of the wiping blade.

[0013] In particular, the first material and the second material comprise at least one crosslinkable polymer.

[0014] The second material contains at least one crosslinking agent for crosslinking at least one crosslinkable polymer of the second material and at least one crosslinkable polymer of the first material and / or the first material comprises at least one crosslinking agent for crosslinking at least one crosslinkable polymer of the first material and at least one crosslinkable polymer of the second material.

[0015] The wiping blade thus obtained allows the lubricated body to advantageously perform the function of a lubricating coating. The fact that at least one lubricated body is extruded in common with the base body and / or is injected and / or molded, compared to the usual manufacturing process used to manufacture wiping blades with a lubricating varnish coating, makes it possible to eliminate at least two manufacturing steps, namely homogenization / activation and solidification, for example, drying and / or hardening of the lubricated varnish coating.In particular, the process allows the application of at least one lubricant, advantageously compared to the current manufacturing process for producing wiper blades with a lubricating varnish coating - directly without environmentally harmful halogenation and without solvents, especially without using additional organic solvents; this results in a process that is simpler to apply, more economically and especially more advantageous for the environment.

[0016] The fact that the first base body material and the second material for at least one lubricated body are extruded and / or injected and / or molded together in the form of a cord (base body-lubricated body), compared with manufacturing processes in which a base body already vulcanized is coated with lubricated varnish, results in better adhesion between the base body and at least one lubricated element serving as a lubricated coating.

[0017] The fact that the second material includes in particular a crosslinking agent for crosslinking the material, used both to crosslink at least one crosslinkable polymer of the second material and also at least one crosslinkable polymer of the first material, and / or the first material comprises at least one crosslinking agent which is designed to crosslink at least one crosslinkable polymer of the first material and at least one crosslinkable polymer of the second material; this crosslinking agent allows for chemical crosslinking bonds, in particular covalent bonds, between the first material and the second material; a strong chemical bond is thus formed between the base body and at least one lubricated body; this bond is significantly stronger than a simple physical attachment; this has an advantageous impact on the reliability of the wiping quality of the wiping blade by a long service life.

[0018] Overall, the process makes it possible to manufacture a wiping blade that is simple, economical and advantageous for the environment and whose wiping quality remains for a long period of time.

[0019] At least the basic body can, for example, be extruded and / or injected and / or molded in the form of two extrusion beads. By way of example, the two extrusion beads can be formed on the two opposite sides of the basic body.

[0020] By way of example, the basic body comprises at least one wiping lip segment, particularly intended for the wiping contact of the wiping blade, at least one tilting spacer segment, and at least one fastening segment. This basic body can be made, for example, on the surface of the wiping lip segment, particularly at the tip of the wiping lip segment. For example, the lubricated body can be made in the form of a double lubricated strip on two opposite sides of the wiping lip segment, particularly at the tip of the wiping lip segment, and / or have, in particular, at least one wiping edge, particularly two wiping edges on the surface of the wiping lip segment, particularly at the tip of the wiping lip segment. The lubricated body is thus advantageously made in functionally important locations.

[0021] In particular, the cord formed by the base body and the lubricated body is extruded or injected or molded in the form of a single profile cord; the base body includes, for example, a wiping lip segment, a tilting spacer segment and a fixing segment.

[0022] Insofar as the base body-lubricated body bead is extruded, injected, or molded in the form of a double-profile bead, the base body may, for example, have two wiping lip segments, two tilting spacer segments, and two fastening segments. The two wiping lip segments may, in particular, be connected to each other on one side or, on the other hand, be connected respectively by a tilting spacer segment to the fastening segment.

[0023] According to one embodiment, the first material and the second material comprise at least one crosslinking agent for crosslinking the material and from the same class of crosslinking agents.

[0024] A class of crosslinking agents corresponds in particular to a class or group of crosslinking agents whose crosslinking is based on a similar crosslinking mechanism. For example, classes of crosslinking agents include, for example, the class of peroxide crosslinking agents and / or the class of sulfur crosslinking agents and / or isocyanate crosslinking agents.

[0025] This allows us to optimize the chemical bond between the base body and a lubricated body.

[0026] The first material and the second material can, in principle, be in particular independent of each other, one or two or more polymers, for example, a crosslinkable polymer and / or two or three or more crosslinkable polymers. For example, the first material and the second material comprise, independently of each other, a crosslinkable polymer of a class of polymers or a mixture of two or three or more crosslinkable polymers of the same class or of a different class, in particular of different polymer classes, for example, a mixture of ethylene-propylene-diene terpolymer and natural rubber or a mixture of poly-chloroprene and natural rubber.

[0027] The term "polymer class" means, in particular, a class or group of polymers obtained from the same monomer or monomers. Examples of polymer classes are the ethylene-propylene-diene (EPDM) terpolymer class and / or the polychloroprene (CR) class and / or the polyisoprene class and / or the natural rubber (NR) class.

[0028] According to another embodiment, the first material and the second material comprise at least one crosslinkable polymer of the same polymer class. In this way, the chemical bond between the base material and at least one lubricated material is advantageously optimized.

[0029] According to another development, the first material and the second material comprise respectively at least one crosslinkable peroxide polymer and at least one peroxide crosslinking agent. This makes it possible to advantageously optimize the chemical bond between the base body and at least one body lubricated with peroxide-crosslinkable polymers such as ethylene-propylene-diene terpolymer (EPDM).

[0030] According to another alternative or complementary embodiment, the first material and the second material comprise at least one sulfur-crosslinkable polymer and at least one sulfur crosslinking agent. Advantageously, this optimizes the chemical bond between the base material and at least one other material. lubricated with sulfur crosslinkable polymers, such as polychloroprenes (CR) and / or polyisoprenes and / or natural rubbers (NR).

[0031] The crosslinking agent contains at least one crosslinking agent component. Where applicable, the crosslinking agents comprise two or more, and where applicable even three, four, or five crosslinking agent components.

[0032] The peroxide crosslinking agent includes in particular at least one peroxide, for example, dicumyl peroxide [CAS 80-43-3] and / or di-(2-tert-butylperoxyisopropyl)-benzene [CAS 25155-25-3] and / or tert-butylcumyl peroxide [CAS 3457-61-2] and / or 2,5-dimethyl-2,5-di(tert-butylperoxy)-hexane [78-63-7] and / or di-tert-butylperoxy [78-63-7]. butyl [110-05-4] and / or 2,5-dimethyl-2,5-di(tert-butylperoxy)hexine-3 [CAS 1068-27-5] and / or butyl-4,4-di(tert-butylperoxy)hexine-3 [CAS 1068-27-5]. butylperoxy) valerate [CAS 995-33-5] and / or l,l,di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane [CAS 6731-36-8] and / or tert-butyl peroxybenzoate [CAS 614-45-9].

[0033] A sulfur crosslinking agent includes, in particular, at least one sulfur donor. For example, the sulfur donor is caprolactam disulfide and / or elemental sulfur. The sulfur crosslinking agent includes at least one accelerator. This accelerator is, for example, dithiocarbamate and / or a thiuram and / or a thiazole and / or a thiazolidine, for example, 3-Methyl-thiazolidine-thion-2 [CAS 1908-87-8] and / or it includes a thiazol-sulfinamide and / or a guanidine. The sulfur crosslinking agent may be supplemented, in particular, by an activator, for example, zinc oxide.

[0034] According to another development, the crosslinking agent of the first material and the crosslinking agent of the second material contain at least one of the same crosslinking agent components. This makes it possible to advantageously optimize the chemical bond between the base material and the lubricated material.

[0035] According to another development, the crosslinking agent of the first material and the crosslinking agent of the second material comprise at least one of the same peroxide and / or at least one of the same sulfur donor and / or at least one of the same accelerator. This optimizes the chemical bond between the base material and at least one lubricated material.

[0036] According to another development, the second material crosslinks more strongly than the first material. This allows for advantageous optimization of the wiping quality of the wiping blade. The base body thus has greater elasticity for the wiping movement. The base body thus has greater hardness for the wiping and sliding function.

[0037] According to another embodiment, the second material contains a higher content of crosslinkable functional groups, for example, double bonds and / or A higher concentration of at least one crosslinking agent component, in particular, a higher concentration of peroxide and / or a higher concentration of accelerator and / or a higher concentration of sulfur donor than the first material. This advantageously allows, particularly for an application of crosslinkable polymer of the same polymer class in the first and second materials, for example, ethylene-propylene-diene terpolymer (EPDM) in the first and second materials or polychloroprene (CR) in the first and second materials, polyisoprene, in particular natural rubber (NR) in the first and second materials, for stronger crosslinking and thus greater hardness of the second material and weaker crosslinking and thus higher elasticity of the first material.

[0038] According to another embodiment, the first material and the second material each comprise at least one peroxide-crosslinkable polymer of the ethylene-propylene-diene terpolymer class and at least one peroxide crosslinking agent. In particular, the second material may have a higher content of crosslinkable functional groups, for example, double bonds, for example, a higher diene content of the ethylene-propylene-diene terpolymer and / or a higher content of bonds with additional double bonds, for example, of polybutadiene and / or polyisoprene and / or ethylene glycol dimethacrylate and / or a higher peroxide concentration than the first material. This results in stronger crosslinking and thus greater hardness in the second material and weaker crosslinking and thus greater elasticity in the first material.

[0039] For example, the first material may have, in relation to its total polymer mass weight, greater than or equal to 90 wt% up to 95 wt% of ethylene-propylene-diene terpolymer, > 3 wt% up to < 5 wt% of at least one bond comprising additional double bonds, for example, of polybutadiene and / or polyisoprene and / or dimethacrylate-ethylene-glycol and > 1 wt% up to < 5 wt% of peroxide. The second material represents, for example, in relation to the weight of the total mass of polymer >65% wt up to <85% wt of ethylene-propylene-diene terpolymer, between >10% wt up to 20% wt of a bond comprising at least one additional double bond, for example, polybutadiene and / or polyisoprenes and / or ethylene-glycol dimethacrylate of which >5% wt up to <15% wt, may comprise a peroxide.

[0040] According to another alternative or additional embodiment, the first material and the second material contain at least one sulfur-crosslinkable polymer of the polychloroprene class and at least one sulfur crosslinking agent. The second material can have a higher concentration of accelerator than the first material. This advantageously results in stronger cross-linking and thus greater hardness in the second material, and less cross-linking and thus greater elasticity in the first material.

[0041] According to another alternative or additional embodiment, the first material and the second material each contain at least one sulfur-crosslinkable polymer from the polyisoprene and / or natural rubber class and at least one sulfur crosslinking agent. Thus, the second material may, in particular, have a higher concentration of sulfur donor and / or a higher concentration of accelerator than the first material. This provides the advantage of greater crosslinking and therefore greater hardness in the second material, and less crosslinking and therefore greater elasticity in the first material.

[0042] According to another development, the second material is a paste. The paste form has the advantage that the solid lubricants contained in the second material will be ground much more finely than if they were used in a suspension. This finer grinding improves the wiping quality of the wiper blade and the wear resistance of the lubricated component, thus increasing the service life of the wiper blade.

[0043] According to another development, the second material further contains at least one solid lubricant, in particular graphite and / or polytetrafluoroethylene (PTFE) and / or polyethylene (PE) and / or molybdenum sulfide (MoS2). The process is particularly advantageous for integrating solid lubricants into the lubricated body layer because it avoids the suspension or dispersion of polymers and solid lubricant in a solvent, thereby expanding the range of possible polymers and increasing the number of usable polymers.

[0044] According to another embodiment, the bond formed by the base body and the lubricated body is strengthened, for example, in a salt bath or in a hot air tunnel oven, in particular, to develop chemical crosslinking bonds between the first material and the second material. This notably allows the first material to be vulcanized and the second material to be hardened. A simultaneous hardening of the first and second materials has the advantage of eliminating at least one step in the process, for example, the solidification of the lubricating varnish layer.

[0045] According to another development, the bead formed by the base body and the solidified lubricated body is cut to produce the wiping blade; in particular, it is cut transversely to the direction of the bead. By producing the base body-lubricated body bead as a single-profile bead, a single cut, especially transversely to the direction of the bead, is sufficient to obtain a wiping blade each time. Since the bead formed by the base body and the lubricated body is a double-profile bead, the double-profile bead is separated by a axial cut, in particular between the two wiping lip segments and then cut transversely to the direction of the cord to obtain two wiping blades each time.

[0046] The invention also relates to a wiping blade, in particular for a windshield wiper, for example, for a vehicle windshield wiper.

[0047] A wiping blade made according to the invention can in particular be observed, for example, by a microscopic shot in section and by an electron microscope in section with an EDX analysis. Brief description of the drawings

[0048] The present invention will be described in more detail below with reference to embodiments of the described process and to the figures in which:

[0049] [Fig. 1] schematic section explaining one embodiment of a manufacturing process according to the invention,

[0050] [Fig.2a] Schematic section of an extrusion tool for obtaining the shape of realization of [Fig.1],

[0051] [Fig.2b] Schematic section of an extrusion tool for obtaining the shape of realization of [Fig.1].

[0052] DESCRIPTION OF EMBODIMENT METHODS OF THE INVENTION

[0053] Figure 1 shows an embodiment of a wiper blade 10 obtained by the process of the invention; this blade is particularly intended for a windshield wiper. The blade comprises a first material 11* for the base body 11 and a second material 12* for at least one lubricated body 12 of the wiper blade 10, in common, to form the base body - lubricated body 100 bead; this bead is in the form of a double-profile bead extruded, injected, or molded. The base body connects two wiper lip segments A, A', two tilting spacer segments B, B', and two fixing segments C, C'; The two wiping lip segments A, A' are connected to each other on one side and, on the other side, connected by a tilting spacer segment B, B' to a fixing segment C, C'. The lubricated body 12 covers a portion of the surface of the base body 11 intended for the wiping contact of the wiping blade 10.In particular, the lubricated body 12 is made in the form of two lubricated strips on opposite sides of the surface of the wiping lip segment A, A' of the base body 11. Thus, the lubricated element 12 is advantageously made in functionally important locations.

[0054] The first material 11* and the second material 12* each have at least one crosslinkable polymer. The second material 12* includes, in particular, at least one crosslinking agent for crosslinking the material and which is intended to crosslink both a crosslinkable polymer of the second material 12* and a polymer crosslinkable polymer of the first material 11*. Alternatively, or in addition, the first material 11* comprises a crosslinking agent suitable for both crosslinking the crosslinkable polymer of the first material 11* and crosslinking the crosslinkable polymer of the second material 12*. In particular, the first material 11* and the second material 12* contain at least one crosslinking agent from the same class of crosslinking agents. For example, the crosslinking agent of the first material 11* and the crosslinking agent of the second material 12* have at least one of the same crosslinking agent components, for example, the same peroxide and / or the same sulfur donor and / or the same accelerator. Furthermore, the first material 11* and the second material 12* comprise at least one crosslinkable polymer from the same class of polymers.

[0055] The second material 12* may in particular be more strongly crosslinked than the first material 11* and comprises at least one solid lubricant, for example, graphite, polytetrafluoroethylene, polyethylene and / or molybdenum sulfide.

[0056] For example, the first material 11* and the second material 12* each have at least one peroxide-crosslinkable polymer, for example, of the ethylene-propylene-diene terpolymer class, and at least one peroxide crosslinking agent. To obtain stronger crosslinking of the second material 12*, this second material 12* will have a higher content of crosslinkable functional groups, particularly double bonds, and / or a higher concentration of at least one crosslinking agent component, in particular a higher concentration of peroxide, than the first material 11*.

[0057] According to other examples, the first material 11* and the second material 12* each have at least one sulfur-crosslinkable polymer, for example, from the polychloroprene and / or polyisoprene classes, in particular natural rubber, and at least one sulfur crosslinking agent. To achieve stronger crosslinking of the second material 12*, this second material 12* will, for example, have a higher concentration of at least one crosslinking agent component, in particular a higher concentration of accelerator and / or a higher concentration of sulfur donor, than the first material 11*.

[0058] The bead 100 formed from the base body and the lubricated body can, for example, be solidified in a salt bath or in a hot-air furnace, in particular to develop cross-linkable chemical bonds between the first material 11* and the second material 12* (this is not shown). The cross-linked bead 100 of the base body and the lubricated body is then, for example, directly after solidification, cut in the salt bath at the location indicated by the dashed line, axially and also transversely to the direction of the bead of the wiping blade 10 (this cut is not shown).

[0059] Figures 2a and 2b show one embodiment of an extrusion tool W, for example, an extrusion nozzle for obtaining the embodiment according to the invention shown in [Fig. 1]. [Fig. 2a] shows a section of the first segment of the extrusion nozzle W in which the basic body is formed. [Fig. 2b] shows another section of a second segment of the extrusion nozzle W in which the lubricated body is co-extruded, co-injected, or co-molded with the basic body. The second nozzle segment can, for example, follow directly after the first nozzle segment without leaving a gap.

[0060] NOMENCLATURE OF MAIN ELEMENTS

[0061] 10 Wiping blade

[0062] 11 Basic body

[0063] 11* First material

[0064] 12 Lubricated body

[0065] 12* Second material

[0066] 100 Lubricated base-body cord

Claims

1. Demands Method for making a wiping blade (10) in particular for a windshield wiper according to which - a first material (11*) is extruded and / or injected and / or molded for a basic body (11) and a second material (12*) for at least one lubricated body (12) of the wiping blade (10) in common in the form of a bead basic body - lubricated body (100), - the lubricated body (12) covering a portion of the surface of the base body (11) intended for the wiping contact of the wiping blade (10), - the first material (11*) and the second material (12*) each comprising respectively at least one crosslinkable polymer, - the second material (12*) comprising at least one material crosslinking agent, for crosslinking at least one crosslinkable polymer of the second material (12*) and at least one crosslinkable polymer of the first material (11*), and / or - the first material (11*) containing at least one material crosslinking agent for crosslinking at least one crosslinkable polymer of the first material (11*) and at least one crosslinkable polymer of the second material (12*), and - the first material (11*) and the second material (12*) respectively have at least one peroxide-crosslinkable polymer of the ethylene-propylene-diene thermopolymer class and at least one peroxide crosslinking agent, the second material (12*) having a higher content of crosslinkable functional groups, in particular double bonds, in particular a higher content of dienes of the ethylene-propylene-diene thermopolymer and / or in particular a higher content of at least one bond comprising additional double bonds and / or a higher concentration of peroxide than the first material (11*), and / or - the first material (11*) and the second material (12*) each have at least one sulfur-crosslinkable polymer of the polychloroprene class and at least one sulfur crosslinking agent, the second material (12*) has a higher concentration of accelerator than the first material (11*) and / or - the first material (11*) and the second material (12*) each have at least one sulfur-crosslinkable polymer of the poly- class isoprene and / or natural rubber and at least one sulfur crosslinking agent, - the second material (12*) has a higher concentration of sulfur donor and a higher concentration of accelerator than the first material (11*).

2. A method according to claim 1, wherein the first material (11*) and the second material (12*) comprise at least one material crosslinking agent belonging to the same class of crosslinking agents.

3. A method according to claim 1 or 2, wherein the first material (11*) and the second material (12*) comprise at least one crosslinkable polymer of the same polymer class.

4. A method according to any one of claims 1 to 3, wherein the first material (11*) and the second material (12*) each comprise at least one peroxide crosslinkable polymer and at least one peroxide crosslinking agent, and / or the first material (11*) and the second material (12*) each contain at least one sulfur crosslinkable polymer and at least one sulfur crosslinking agent, respectively.

5. A method according to any one of claims 1 to 4, wherein at least one crosslinking agent of the first material (11*) and at least one crosslinking agent of the second material (12*) comprise at least one of the same crosslinking agent component.

6. A method according to any one of claims 1 to 5, wherein the crosslinking agent of the first material (11*) and the crosslinking agent of the second material (12*) have at least one of the same peroxide and / or at least one of the same sulfur donor and / or at least one of the same accelerator.

7. A method according to any one of claims 1 to 6, wherein the second material (12*) is more strongly crosslinked than the first material (11*).

8. A method according to any one of claims 1 to 7, according to which the second material (12*) has a higher content of crosslinkable functional groups in particular double bonds and / or a higher concentration of at least one component of crosslinking agent in particular a higher concentration of peroxide and / or a higher concentration of accelerator and / or a higher concentration of sulfur donor than the first material (11*).

9. A method according to any one of claims 1 to 8, wherein the second material (12*) is pasty.

10. A method according to any one of claims 1 to 9, wherein the second material (12*) contains at least one solid lubricant, in particular graphite and / or polytetrafluoroethylene and / or polyethylene and / or molybdenum sulfide.

11. A method according to any one of claims 1 to 10, wherein the base body-lubricated body bead (100) is solidified, in particular in a salt bath or in a hot air passage furnace, in particular by forming cross-linked chemical bonds between the first material (11*) and the second material (12*).

12. A method according to any one of claims 1 to 11, wherein the lubricated base-body bead (100) is cut at least once, in particular transversely to the bead direction to obtain the wiping blade (10), and in particular the lubricated base-body bead (100) is cut in the form of a double profile axially along the double profile bead and transversely to the bead direction to obtain wiping blades.

13. Wiper blade (10) in particular for a windshield wiper, in particular for a vehicle windshield wiper resulting from the process according to any one of claims 1 to 14.