MX2012010924A

MX2012010924A - Method for producing a wiper blade.

Info

Publication number: MX2012010924A
Application number: MX2012010924A
Authority: MX
Inventors: Yves Verburgh
Original assignee: Bosch Gmbh Robert
Priority date: 2010-03-23
Filing date: 2011-02-15
Publication date: 2012-10-10
Also published as: WO2011117026A2; EP2550142A2; DE102010003139A1; WO2011117026A3

Abstract

The present invention relates to a method for producing a moulded body, in particular a vulcanized moulded rubber body. In method step a), the moulded body is first of all formed from a vulcanizable material. A thermosetting coating can subsequently be applied to the surface of the moulded body. In method step b), the moulded body is dipped into a heated silicone bath in order to vulcanize the vulcanizable material of the moulded body and/or to cure the thermosetting coating.

Description

PROCEDURE TO PRODUCE A RUBBER FOR WIPER LIM FIELD OF THE INVENTION The present invention relates to a method for producing a molded body, especially a molded body of vulcanized rubber, for example a rubber for windshield wipers or a seal.

BACKGROUND OF THE INVENTION The vulcanization of rubber molded bodies, for example to produce wiper blades, requires the effect of heat for a certain period of time. The effect of heat is preferably carried out by immersing the molded rubber body in an indirect heat transfer medium, for example a salt bath of one or more molten alkali nitrite and / or alkali nitrate salts. The molten alkali metal nitrate-alkali nitrate salts are characterized in particular by a lower melting range of 138-142 ° C, high thermal capacity and high thermal conductivity.

The molten materials of alkali nitrite-alkali nitrate salts have however a density of 1.9 kg / dm3 at 2.0 kg / dm3, which is higher than the density of the common rubber moldings, in particular from 1.0 kg / dm3 to 1.5 kg / dnv. For that reason the rubber molded bodies tend to float in the molten material and therefore must be forcedly submerged in the molten salt. This on the one hand is mechanically complicated and on the other hand is associated with the risk of deformation of the rubber profile.

Furthermore, in the case of the molten alkali metal nitrate-alkali nitrate salts, secondary reactions can occur that lead to the formation of poisonous nitrosamines. For example nitrogen components containing nitrogen in the rubber molded body, such as vulcanization accelerators, UV stabilizing agents and thermal stabilization media, react to form nitrosamines.

In addition, the molten alkali metal nitrate-alkali nitrate salts are classified as poisonous and flammable due to their nitrite content. In addition, the permitted content of nitrite in waste waters within the countries of the European Union currently varies greatly and therefore care must be taken during disposal.

In addition, the surface of the rubber profiles vulcanized in the molten alkali-nitrate-alkali nitrate salts is released from the salt residues adhering by means of a brushing process. When this deteriorates the appearance, and especially functionality in the case of rubber windshield wipers for motor vehicles.

In addition, the molten salts of alkali nitrite-alkali nitrate absorb carbon dioxide, which leads to the alkali metal carbonate precipitating out of the molten material at low temperatures. When this can lead to a worsening of the vulcanization products and to the interruption of the vulcanization process, the alkali carbonate content should be constantly monitored.

SUMMARY OF THE INVENTION The object of the present invention is a method for producing a molded body, especially a vulcanized molded body, for example a rubber molded body, for example for sliding contact applications, which encompasses the following process steps: a) molding a molded body from a vulcanizable material, and b) immerse the molded body in a silicone bath.

Under a silicone bath in the context of the present invention is meant in particular a bath (immersion), which includes liquid silicone. Among other things, the silicone bath in the framework of the present invention serves as a means of thermal transmission, especially indirect.

The silicone baths have on the one hand the advantage that they do not have the aforementioned disadvantages of the molten nitrite salts to the alkali nitrate-nitrate. On the other hand many sale silicone baths can be heated to temperatures of approximately 300 ° C. In addition, the silicone baths generally have a lower or similar density than the molded body to be treated, therefore the molded bodies usually must not be forcibly submerged in the silicone bath by the application of a mechanical force. This in turn has the advantage that deformation of the molded body during the dive can be avoided.

The use of a hot silicone bath also has the advantage that during the immersion in the silicone bath, the silicone molecules can adsorb on the surface of the molded body and / or can be partially or totally bonded to the end layer of the molded body close to the surface. Thus, by means of process step b), the anti-adhesion and sliding properties of the molded body can be continuously improved, and the coefficient of friction of the molded body can be constantly reduced. These are important functional surface properties for the molded body for sliding contact applications, eg windshield wipers or seals for window panes.

Particularly during the immersion in the silicone bath, heat can be transferred to the molded body, through which the vulcanizable material of the molded body is vulcanized. Therefore, the molded body can be immersed in the silicone bath in process step b) to vulcanize the vulcanizable material of the molded body.

Unlike hot air, silicone baths have the advantage of having a high heat transfer and a more uniform heat effect, due to which the molded body can be vulcanized more quickly and uniformly than with the use of hot air. In addition, the molded body can be protected from damage caused by oxygen by the silicone bath.

Furthermore, by the process according to the invention, molded rubber bodies can be produced, for example from natural rubber, chloroprene rubber, ethylene-propylene-diene rubber (EPDM), ethylene-propylene rubber (EPM) and mixtures thereof, which they have good properties of anti-adhesion and water-repellent properties comparable to vulcanized silicone rubbers, without presenting the inherent disadvantages of vulcanized silicone rubbers, such as high material costs, long vulcanization times and high demands on the extrusion capacity , which promote the use of reinforcing agents to obtain the shape.

DETAILED DESCRIPTION OF THE INVENTION Within the framework of a preferred embodiment, the process between process steps a) and b) present the step: bO) apply a coating that hardens with heat on the surface of the molded body.

For example, the heat-hardening coating can be a heat-hardening sliding coating, especially a heat-hardening lacquer. These types of sliding coatings are frequently used to reduce the friction coefficients of wipers and window seals.

The coating according to step bO) of the process can be carried out by applying a preferably aqueous coating composition containing a solvent to the surface of the molded body and then drying it of the solvent. In the process step b) the silicon bath can be induced by the monomer and / or monomeric adducts in the coating composition and / or the crosslinking of the polymer chains in the coating composition.

During the immersion in the silicone bath, the silicone molecules can adsorb on the surface of the coating and / < chemically and / or physically or fully or partially bound in the extreme layer close to the surface of the coating, by the process step b) can be improved The water-repellent properties and the anti-adhesion properties of the coating as well as reducing the coefficient of friction of the coating.

In space during the immersion in the silicone bath heat can be absorbed into the coating, by which the coating hardens. Therefore the molded body in process step b) can also be submerged in < 1 silicone bath, to harden the coating qu: hardens with heat.

When: in the silicone bath a greater heat transfer is possible on the molded body and the coating with the hot air, the selling coating can harden more rapidly by the use according to the invention of a silicone bath that with the use of hot air. Furthermore, by using a silicone bath in accordance with the invention, a more uniform thermal effect on the coating can be obtained when using hot air. In addition the molded bodies and the coating with the silicone bath are protected from IOI; damage caused by oxygen.

When the molded body does not vulcanize before immersion in the silicone bath in process step b), or in spice: it is only partially cured in process step a) which will be described later, in process step b) they can simultaneously vulcanize the vulcanizable material and harden the coating. Through vulcanization and simultaneous hardening vei. A better adhesion of the coating to the molded body can be obtained better. Furthermore, by simultaneous curing and curing, in particular in the case of the previously unvulcanized molded body, multiple heating of the molded body is avoided.

In another embodiment, the procedure between process steps a) and bO) or between process steps a) and b) presents the step e procedure: al) vu. totally or partially hardening the vulcanizable material of the molded body.

When the molded body does not vulcanize prior to immersion in the silicone bath in process step b), or in the case only partially vulcanizes in process step a) and does not apply coating that hardens with ca. or, in process step b), the silicone molecules can be adsorbed on the surface of the coating and / or chemically and / or physically bound totally or partially in the end layer close to the surface of the coating, whereby they can the water-repellent properties and the anti-adherence properties of the coating are improved and the coefficient of friction of the coating is reduced.

When the molded body does not vulcanize before the immersion in the L: silicone year in the process step b), or in particular it is only partially cured in the process step a) which will be described later, in the process step b) the vulcanizable material can be vulcanized simultaneously and the coating hardened, whereby a better adhesion of the coating to the molded body can be obtained.

When the molded body before being immersed in the silicone bath in process step b) is completely cured in process step a), in the process step b) the coating can be hardened by bonding the silicone molecules.

Preferably the molded body, when performing process step a) is only partially vulcanized. ;, at hot silicone bath temperature and the immersion time, this is the period of time during which the rubber molded body is used in the silicone bath, depends on the rubber material of the molded body and the mde, the molded body and / or the material of the coating and the thickness of the coating layer. n the framework of another preferred embodiment, in process step b): - the immersion time, during which the molded body is immersed in the silicone bath, and - the temperature of the silicone bath, to which the silicone bath is qualified, they are selected in such a way that the molded body is vulcanized and / or the coating hardens. v ', 1 silicone bath can be heated in process step D) for example at a temperature of at least 150 ° C, in particular at least 180 ° C, for example at at least 200 ° C.

In the frame of another preferred embodiment, in the process step b) the immersion time, during which the molded body is immersed in the silicone bath, in a range Jo > 0. '3 minutes to < 10 minutes, especially > 0.5 minutes.-| < 6 minutes, for example from > 0.9 minutes to < 3 minutes, ·; the silicone bath presents a temper the range ·: > 15C ° C minutes at < 300 ° C, for example 180 ° C minutes. · < 250 ° C, especially from > 200 ° C minutes at < 220 ° C. An installation time of that type and the temperature of the silica bath. i has proved to be particularly advantageous in the production of windshield wipers.

The silicone bath can include both a silicone and a mixture of two or more silicones.

The density of the molded bodies of common vulcanized materials, for example materials of cau: -ao, is found at ambient temperatures (20 ° C) usually in the range; < ü kg / dm3 to < 1.5 kg / dm3.

To simplify the immersion of the body in the silicone body, it has been shown to be advantageous when the silicone has a density that is less than or equal to the density of the molded body immersed in the material. Immersible lcani / .able of the molded body. , ?? the frame of another preferred embodiment the silicone ring exhibits a density, in speci? to the temper. your i to which the silicon bath is heated, in the stage of; procedure b), which is less than or equal to the oasity of the unmouldable molded cuorj.a or the vulcan material: immersible material. of the molded body.

When the silicone bath includes one of two or two; silicones, the density of the silicone bath can be adjusted not only by means of a simple selection of the silicones from the silicone bath, but also by: a proportion between the silicones in the silicon 1 year.

In another preferred embodiment, the silico bath at room temperature (20 ° C) has a density in the range of > 0.67 kg / dm3 to < 1.15 kg / dm3, for example c, 5 > 0.94 kg / dm3 to < 1.11 kg / dm3, especially > 0.94 kg / dm3 to < 1.0 kg / dm3. This has the advantage that the molding of a molding body which at a room temperature (20 ° C) has a density in the range of > 1.0; -. G / dm3 to < 1.5 kg / dm3.

In another preferred embodiment, the silicoi bath at room temperature (20 ° C) has a viscosity: da! kinematics of > lOxlO "6 n ^ s" 1 a < 2000xl0 ~ 6 m2s "1, for example do> 25x10" 6 mV1 to < 1000xl0"6 m2s_1, especially from> 50xl0" c m2.:"1 to < 500xl0"6 m2s_1.

In a further preferred embodiment, the silica bath: .a includes a phenylmethylpolysiloxane and / or a polydi: -: ethylsiloxane (PD S). In particular, the silicone bath can be based on a phenylmethylpolysiloxane and / or polydii-3-ylsilocano. Eventually the silicone bath can consist of a polymethyl polysiloxane and / or polydimethylene glycol. ? 1 silicone bath can also contain compor. reactive agents which participate in the vulcanization reaction on the surface of the molded body or in the reaction; - > n of hardening on the surface of the coating, in particular during the group addition reaction; -, and unsaturated Fillers, for example isoprene, chlororen and / or diene groups. For example, the silicone bath, especially in addition to phenylmethylpolysiloxane and / or polyethylene, can be at least one polymer.

The frame of another preferred embodiment of the silicon bath includes, in addition to the phenylmethylpolysiloxane and / or polyethylene loxane, at least one functional polysiloxane: i. < io, selected from the group consisting of polymers functionalized with mercapto, functional polysiloxanes with vinyl, polysiloxanes functionalized with: .cry (.: .D and their mixtures.

! |.; Special the silicone bath can contain a poly.- \ '-'. ..e functionalized, selected from the group with? 'in' · of dimethylpolysiloxane functionalized with mere .. ',, met i lpolisiloxane functionalized with vinyl, dimei. po.l i.-i loxane functionalized with hydrogen and its mixtures.; .

For example, the silicone bath contains at least one vinyl dimethyl-terminated polydimethylsiloxane and / or at least one vinylmethylsiloxane copolymer, for example one or more of the products marketed under the trade names PS 445, PS 424, PS 255 of the United Chemical Technologies, Bristol, PA, USA. PS 445 is here a vinyl-terminated dimethylpolysiloxane with low molecular weight, PS 424 is a copolymer of poly (dimethylsiloxane) - (7.5%) (methylvinylsiloxane) with low molecular weight and PS 225 and a copolymer poly (dimethylsilocano) - (0.1 -0.3%) (methylvinylsiloxane) with a high molecular weight.

Alternatively or in addition to the aforementioned vinyl-functionalized polysiloxanes the silicone bath may contain at least one mercapto functionalized polysiloxane, for example one or both of the products marketed under the trade names PS 405 and PS 849 of United Chemical Technologies, Bristol, PAf USA PS 405 is here a branched polydimethylsiloxane with mercaptopropyl groups at the branching sites and PS 849 is a copolymer of poly (dimethylsiloxane) - (1-3%) (methylmercaptopropylsiloxane).

Alternatively or in addition to the aforementioned vinyl and mercapto functionalized polysiloxanes, the silicone bath can contain at least one polysiloxane functionalized with water, especially dimethyl polysiloxane, for example the products marketed under the trade name PS 120 of United Chemical Technologies, Bristol , PA, USA Here PS 120 is a dimethylpolysiloxane functionalized with hydrogen with low molecular weight.

The aforementioned vinyl, mercapto and hydrogen functionalized polysiloxanes take part in the vulcanization reaction on the surface of the vulcanizable material, which for example can be natural rubber; chloroprene rubber; a mixture of natural rubber and chloroprene rubber; ethylenepropylenediene rubber (EPDM); or a mixture of natural rubber and ethylene propylene diene rubber, wherein the ethylene propylene diene rubber (EPDM) can be exchanged in whole or in part by ethylene propylene rubber (EPM), and thus they can be bonded to the molded body.

In the context of another preferred embodiment, the vulcanizable material consists of at least one component selected from the group consisting of natural rubber, synthetic rubbers, especially isoprene rubber, chloroprene rubber, ethylene propylenediene rubber (EPDM), eitlenopropylene rubber ( EPM), silicone rubbers, vulcanizable thermoplastic elastomers and their mixtures. Thus, the vulcanizable thermoplastic elastomers can be selected from the group consisting of polydienes, polybutadienes and / or polyisoprene, natural rubber, diene copolymers such as copolymers of butadiene and / or isoprene with other copolymerizable monomers, for example selected from the group consisting of styrene, α-methylstyrene , acrylates, methylisopropenyl, ketones, isobutyls, acrylonitrile, unsaturated carboxylic acids and mixtures thereof, halogenated rubber, such as polychloroprene and / or fluorinated rubbers, copolymers of one or more monoolefins with a monomer which introduces unsaturated groups into the copolymer, for example terpolymer, ethylene / propylene dicyclopentadiene, polyurethane rubbers vulcanizable with sulfur, butyl rubbers with at least 0.8% unsaturated positions and mixtures thereof. Thus, the mixtures can be for example copolymer mixtures of natural rubber / butadiene-styrene and / or mixtures of copolymers of a copolymer saturated with ethylene and / or propylene with an unsaturated copolymer of ethylene and / or propylene and a monomer, which introduces groups unsaturated in the copolymer.

In addition, the vulcanizable material may contain one or more additives, for example antioxidants, processing aids, plasticizers, vulcanization accelerators, UV stabilizing agents, thermal stabilizing agents, sulfur, sulfur-donating materials, peroxides, metal oxides such as magnesium, calcium oxide, zinc oxide, organic acids, such as stearic acid and / or carbon black.

The heat-hardening coating may in particular contain one or more polymerizable and / or crosslinkable components, for example a methylated iminomelamine plasty, for example hexametoxymethylmelamine.

In addition, the heat hardening coating may contain one or more fillers, in particular lubricants, such as graphite.

Preferably the weight of the fillers, especially the graphite, of the heat-curable coating to the weight of the polymerizable and / or crosslinkable components of the coating that hardens with heat in a ratio of 0.40 to 0.50, especially 0.45 to 0.48, for example approximately 0.46. Such a proportion has proved advantageous for bonding the graphite particles permanently in the polymer matrix to obtain excellent abrasion resistance on hydrophobic and hydrophilic glass plates.

In addition, the hardenable coating may contain one or more thickeners, for example selected from the group consisting of polyacrylates, cellulose polymers, vinyl acetate-meleic acid copolymers, styrene-maleic acid copolymers, hydroxymethylene polymers, polyethylene glycols, hydroxypropylene polymers, polyvinyl alcohols, polyacrylamide and acrylamide copolymers and mixtures thereof.

The solvent-containing coating composition for producing the coating in process step bO) may contain a solvent selected from the group consisting of glycol ethers, for example butyl glycol and / or diethylene glycol butyl ether (butylcarbitol), 2-methoxypropanol, propylene glycol , ethanol, isopropanol, water and their mixtures.

Basically, in the context of the present invention, the molding in the process step a) and / or the dipping in the process step b) can be carried out either continuously or discontinuously, in the form of a so-called batch process. Preferably, process steps a) and b) are carried out either continuously or discontinuously. In order to avoid interruptions in the process and to shorten the production time, in a particularly preferred manner, process steps a) and b) are carried out continuously.

After immersing in the silicone bath for a certain period of immersion time, the molded body can be removed from the silicone bath. If necessary, the silicone in excess of the silicone bath adhered to the molded body can be removed in a process step c) subsequent to process step b). Here, the silicone is preferably removed by a technique with which the silicone molecules adsorbed on the surface of the body or bonded in an end layer of the surface and / or a coating optionally applied on the molded body are not removed or damaged. For example the removal of the excess silicone from the silicone bath adhered to the molded body by cleaning the molded body with a cloth, for example a cotton or fleece fabric.

To facilitate handling and avoid possible deformation of the molded body, the method can include between process steps b) and e), a process step cO) cooling the molded body, in particular at room temperature.

After process step c) the process can include process step d): dividing the molded body into at least 2, especially a plurality of molded body parts. In this way, many products can advantageously be produced by a process step. For example, windshield wipers and / or seals, especially seals for sliding windows, can be produced with the method according to the invention, such that a molded body is first produced in the form of a double or multiple profile, which then it is divided, in particular cut, into two or more individual profiles along the longitudinal axis.

Another object of the present invention is a molded body especially for sliding contact applications, which is produced by a method according to the invention. For example, the molded body can be a wiper blade for a windshield wiper, for example of a motor vehicle, or a seal, in particular for sealing two sliding elements sliding against each other, for example a sliding window, for example of a vehicle motor.

Examples Other advantages and advantageous embodiments of the objects according to the invention are illustrated by examples and the following description is described. It should be noted that the examples are only descriptive in nature and are not intended to limit the invention in any way.

Example 1 Double profiles for producing windshield wipers for motor vehicles were extruded from a rubber material with a composition in accordance with Table 1: Table 1 Example the One of the double profiles extruded with a rubber material with a composition according to Table 1, was immersed for 2 minutes in a silicone bath heated to 210 ° C. The silicone bath includes a phenylmethylpolysiloxane, which is marketed under the trade name Dow Corning 510 from Dow Corning Corporation (Michigan, USA) and which at room temperature has a viscosity of 100 cSt (= 100 iO'W1).

The heat transferred to the double profile through the silicone bath is sufficient to vulcanize the rubber material of the double profile in the course of 2 minutes. After removing the double profile of the silicone bath and cooling the double profile, the rubber material of the double profile has completely vulcanized. The surface of the double profile is uniform and strongly water-repellent. After cleaning the double profile with a cotton cloth, its surface was dry, not greasy and even strongly water-repellent. An adhesive strip applied to one of the surfaces of the double profile. It can be easily removed, which is a sign of good anti-sticking properties.

The double profile was then cut along the longitudinal axis in two individual profiles and mounted in a wiper system. The profiles present a uniform cleaning quality without leaving streaks. Example Ib Another double extruded profile of a rubber material with a composition according to Table 1 was not vulcanized directly after extrusion. Instead of this, after the extrusion, an aqueous coating composition with a composition according to Table 2 was first applied to both sides of the double profile and dried under the evaporation of the solvent: Table 2 Then the double profile was divided into two pieces.

A. Vulcanization and hardening in the silicone bath One of the two pieces of double coated profile was immersed for 2 minutes in a silicone bath based on phenylmethylpolysiloxane (Dow Corning 510, Dow Corning, Germany) heated at 210 ° C. The vulcanization of the rubber material was carried out here simultaneously with the hardening of the coating.

The hardened coating was rubbed with a cotton ball moistened with methyl ethyl ketone (MEK) to determine the degree of hardening. No coating detachment was observed even after 150 double rub processes (1 double rub process = one outward movement and one backward movement).

The double profile was cut along the longitudinal axis in two individual profiles. The cutting edges showed no damage to the coating or detachment of the coating from the cutting edges. The profiles mounted on a wiper system have a uniform cleaning quality without leaving streaks.

B. Vulcanization and hardening in the silicone bath The other part of the double coated profile was treated for 10 minutes in a hot air oven with hot air at a temperature of 150 ° C, whereby the coating hardened. A hardened coating with a layer thickness of 4 μp was obtained? and a composition in accordance with table 3.

Table 3 The hardened coating was rubbed with a cotton ball moistened with methyl ethyl ketone (MEK) as in the previous example. After 30 to 40 double rubbing processes, a release of the coating was observed.

Example 2 Double profiles for the production of motor vehicle windscreen wipers were extruded with a rubber material with a composition in accordance with table 4: Table 4 Example 2a A double profile extruded with a rubber material with a composition according to table 4 was immersed for 1.4 minutes in a silicone bath heated to a temperature of 220 ° C. The silicone bath includes a phenylmethylpolysiloxane, which is marketed as Dow Corning 510 from Dow Corning Corporation (Michigan, USA) and which at room temperature has a viscosity of 100 cSt (= 100 lO'Vs "1).

The heat transferred to the double profile by the silicone bath is sufficient to vulcanize a rubber material of the double profile in the course of 1.4 minutes. After removing the double profile of the silicone bath and cooling the double profile, the rubber material of the double profile was completely vulcanized. The surface of the double profile was uniform and strongly water-repellent. After rubbing the double profile with a cotton cloth, its surface was dry, not greasy and even strongly water-repellent. An adhesive strip applied to one of the surfaces of the double profile. It can be easily removed, which is a sign of good anti-sticking properties.

The double profile was then cut along the longitudinal axis in two individual profiles and mounted in a wiper system. The profiles present a uniform cleaning quality without leaving streaks. Example 2b Another double extruded profile of a rubber material with a composition in accordance with Table 4 was not vulcanized directly after extrusion. Instead of this, after the extrusion, an aqueous coating composition with a composition according to Table 2 was first applied to both sides of the double profile and dried under the evaporation of the solvent.

Then the double profile was divided into two pieces.

A. Vulcanization and hardening in the silicone bath One of the two pieces of double coated profile was immersed for 1.4 minutes in a silicone bath based on phenylmethylpolysiloxane (Dow Corning 510, Dow Corning, Germany) heated at 220 ° C. The vulcanization of the rubber material was carried out here simultaneously with the hardening of the coating.

The hardened coating was rubbed with a cotton ball moistened with methyl ethyl ketone (MEK) to determine the degree of hardening. No detachment of the coating was observed even after 150 double rub processes.

B. Vulcanization and hardening in the silicone bath The other part of the double coated profile was treated for 10 minutes in a hot air oven with hot air at a temperature of 150 ° C, whereby the coating hardened. A hardened coating with a layer thickness of 4 μl and a composition according to Table 3 was obtained.

The hardened coating was rubbed, under the same conditions as the previous example, with a cotton ball moistened with methyl ethyl ketone (MEK). After 25 to 30 double rubbing processes a coating detachment was observed.

Claims

NOVELTY OF THE INVENTION Having described the present invention as above, it is considered as a novelty and therefore the content of the following is claimed as property: CLAIMS

1. A process for producing a molded body, especially a vulcanized molded body, for example a rubber molded body, for example for sliding contact applications, characterized in that it encompasses the following process steps: a) molding a molded body from a vulcanizable material, and b) immerse the molded body in a silicone bath.

2. The method according to claim 1, characterized in that the process between process steps a) and b) present the step: bO) apply a coating that hardens with heat on the surface of the molded body.

3. The process according to claim 1 or 2, characterized in that the process between process steps a) and bO) or between process steps a) and b) presents the step e procedure: a) fully or partially vulcanizing the vulcanizable material of the molded body.

4. The method according to claims 1 to 3, characterized in that in process step b): - the immersion time, during which the molded body is immersed in the silicone bath, and - the temperature of the silicone bath, to which the silicone bath is heated, they are selected in such a way that the molded body is vulcanized and / or the coating hardens.

5. The method according to claims 1 to 4, characterized in that in the process step b) - the immersion time, during which the molded body is immersed in the silicone bath, in a range of > 0.5 minutes to < 10 minutes, and / or - the silicone bath has a temperature in the range of > 150 ° C minutes at < 300 ° C.

6. The process according to claims 1 to 5, characterized in that the silicone bath has a density that is less than or equal to the density of the immersible molded body.

7. The process according to claims 1 to 6, characterized in that the silicone bath at room temperature has a density in the range of > 0.67 kg / dm3 to < 1.15 kg / dm3.

8. The process according to claims 1 to 7, characterized in that the silicone bath at room temperature has a kinematic viscosity of > lOxlO "6 m2s_1 a < 2000xl0" 6 m2s "1.

9. The process according to claims 1 to 9, characterized in that the silicone bath includes a phenylmethylpolysiloxane and / or a polydimethylsiloxane.

10. The process according to claims 1 to 9, characterized in that the silicone bath contains at least one functionalized polysiloxane, selected from the group consisting of mercapto functionalized dimethylpolysiloxanes, vinyl-functionalized dimethylpolysiloxanes, dimethylpolysiloxanes functionalized with hydrogen and mixtures thereof.

11. The process according to claims 1 to 10, characterized in that the vulcanizable material consists of at least one component selected from the group consisting of natural rubber, synthetic rubber, vulcanizable thermoplastic elastomers and mixtures thereof.

12. A molded body for sliding contact applications, for example a wiper blade or seal, produced by a method according to one of claims 1 to 11.