Patent Application
20110143113
The invention relates to sealing strips for vehicle windows. Each of these sealing strips comprises at least one first, elastic layer made of a thermoplastic elastomer and a second, harder layer. The first layer is implemented to exert a sealing function between a construction element of a vehicle and a surface of a windowpane movable in relation to the sealing strip. The second layer is implemented as a visible cover for at least the largest, otherwise visible part of the first layer. The first and second layers are bonded to one another over essentially the entire length of the sealing strip.
Sealing strips for vehicle windows have been known for some time and ensure the seal of the junction of a windowpane to a construction element of the vehicle, so that environmental influences, such as rainwater, dirt, and/or wind may be kept out of the vehicle interior. Special requirements are placed in particular on sealing strips of movable windowpanes, whether these windows are displaceable exclusively linearly (vertically or horizontally), foldable, or movably nonlinearly (e.g., rotatable). These requirements comprise high elasticity and longevity of the seal elements, an appealing visual quality of the sealing strips, and a pronounced stability in relation to environmental influences. In connection with the present invention, all vehicles driven by motors, such as automobiles, trucks, locomotives, railway cars, and ships are referred to as vehicles. Without restricting the scope of the invention, however, only examples from the automobile industry are used for explaining the invention. All transparent, translucent, or opaque, flat or curved, essentially planar formations made of glass, plastic (e.g., polycarbonate or Plexiglas®=PMMA), or possibly metal (e.g., slides made of sheet metal) are referred to hereafter as movable windowpanes, if they are movable in any way in relation to at least one sealing strip.
A sealing strip according to the species is known from U.S. Pat. No. 6,422,571 B1 (cf. appended
Further sealing strips for vehicle windows are known from DE 39 01 093 C2. A first sealing strip 1 (cf. appended
Sealing strips for vehicle windows are also known from EP 1 826 050 A1. In contrast to U.S. Pat. No. 6,422,571 B1, this document discloses an external sealing strip 1 and an internal sealing strip 1′ in the area of the shaft opening in the automobile side door. The side windowpane 6 may be lowered completely into a window shaft concealed in the side door through this opening (cf. appended
The object of the present invention comprises suggesting an alternative sealing strip for vehicle windows.
This object is achieved according to a first aspect by the features of independent Claim 1, in which a sealing strip for vehicle windows is suggested, which comprises at least one first, elastic layer made of a thermoplastic elastomer and one second, harder layer. The first layer is implemented to exert a sealing function between a construction element of a vehicle and a surface of a windowpane movable in relation to the sealing strip. The second layer is implemented as a visible cover for at least the largest, otherwise visible part of the first layer, the first layer and the second layer being bonded to one another over essentially the entire length of the sealing strip. The sealing strip according to the invention is characterized in that the second layer is made of a transparent or translucent polyamide.
This object is achieved according to a second aspect by the features of independent Claim 15, in which a use of thermoplastics for producing multilayer sealing strips for vehicle windows is suggested, sealing strips being produced which comprise:
Further features according to the invention and preferred embodiments of the invention result from the dependent claims.
Advantages of the sealing strip according to the invention comprise:
Sealing strips for vehicle windows known from the prior art and a selection of exemplary, preferred embodiments of the sealing strip according to the invention are schematically shown in the appended figures, without these figures restricting the scope of the invention. In the figures:
The second, harder layer 13 is preferably implemented so that a first edge 24 of the mounted sealing strip 11 adjoins as close as possible to the surface 25 of the construction element 14, and that a second edge 26 is also located at a small distance to the surface 15 of the windowpane 16. It is thus ensured that this cover layer 13 protectively and practically completely covers the softer, elastic retention layer 12 of the sealing strip 11.
It is especially preferable for the cover layer 13 to be adapted in its shaping to the shape of the particular construction element 14 on which this sealing strip 11 is fastened, and/or to supplement this shape. This cover layer 13 preferably comprises effect pigments and/or colorants, so that a color adaptation to the particular construction element 14 may also be provided.
This effect layer 17 preferably comprises effect pigments and/or colorants so that a color adaptation to the particular construction element 17 may also be provided.
However, the effect layer 17 may also comprise a luminescence or phosphorescence layer or be implemented as such. In addition, the cover layer may comprise effect pigments and/or colorants and/or luminescent pigments, which—for example, depending on the current illumination situation—work together with the effect pigments and/or colorants of the effect layer. Instead of or in addition to sealing lips 27 (cf.
However, the effect layer 17 may also comprise a luminescence or phosphorescence layer or be implemented as such. In addition, the cover layer may comprise effect pigments and/or colorants and/or luminescent pigments, which—for example, depending on the current illumination situation—work together with the effect pigments and/or colorants of the effect layer. Instead of or in addition to sealing lips 27 (cf.
The sealing strips 11 according to the invention are preferably produced in an extrusion method, in particular a co-extrusion method. Alternatively, and particularly for producing geometrically complex shapes, for example, multicomponent injection molding methods may also be used. The lamination technique is also alternatively applicable.
In experiments, various variants of multilayer profiles according to the invention were produced on a co-extrusion system of the manufacturer NOKIA MAILLEFER. The multilayer die head was fed by corresponding extruders, which were charged with plastic material (granulate) provided for the corresponding layers. Granulates were melted in the extruders and conveyed as the melt to the corresponding channels of the die head. The continuously extruded multicomponent profile was cooled using typical devices and drawn off at a velocity of 5 m per minute. In following Table 1 having the materials used for three selected examples, the first layer corresponds to the elastomer layer 12, which faces toward the windowpane 16 in later use, while the opposing layer 13 made of transparent polyamide is visible later to observers.
Explanations of the materials follow.
In the three examples shown, a metallic pigment in the form of a masterbatch (abbreviation MB; as known to those skilled in the art, a concentrate of pigment particles dispersed in a polymer) was added in each case to the transparent polyamide for a layer to achieve an especially good visual appearance. It is to be noted here, however, that all embodiments having transparent or translucent polyamide without effect pigments and/or without additives are also according to the invention, of course. The three examples shown are therefore not to be understood as restrictive, but rather represent exemplary variants for 2, 3, and 4 layer constructions. In examples B and C (as specified in Table 1) a cover layer 13 made of the same transparent polyamide, but without effect pigments, was coextruded over the effect layer. The visual depth effect was thus reinforced and simultaneously a very smooth surface was achieved.
The metallic pigment masterbatches used, having the names “Silver PA, class 1” and “Silver PA, class 2” are concentrates of aluminum particles in a transparent polyamide.
The temperatures of the extruders selected for the examples according to the invention are specified for the materials of the corresponding layers in Table 2.
The two selected classes of metallic pigments resulted in different visual effects on the coextruded samples, namely a uniformly appearing coloration by fine aluminum powder of class 1 on one hand, which is very similar to a vehicle body coloring (in silver) and is intended as a lacquer substitute, and an increased optical depth effect by the use of somewhat coarser aluminum flakes of class 2 on the other hand.
Further explanations of the materials used in the examples and generally suitable for the invention now follow:
Grilamid® TR 90 (available from EMS-CHEMIE AG, Domat/Ems, Switzerland) is the transparent polyamide PA MACM 12. When followed by the additional identifier UV, this means that the corresponding polyamide molding compound additionally contains a UV stabilizer additive. More extensive explanations of the polyamides are appended below.
ADMER is a registered trade name of the Japanese company Mitsui for adhesion-modified polymers. Admer type QB 510 is a polypropylene grafted with maleic acid anhydride. A bonding agent layer 18 made of such a material or another suitable material is used as an intermediate layer if the selected thermoplastic elastomer and the polyamide do not adhere directly to one another (as in example C; cf. also
SANTOPRENE is a registered trade name of the company Advanced Elastomer Systems for thermoplastic synthetic rubber. The normal types are a mixture or alloy of EPDM elastomer and polypropylene (vulcanized and/or cross-linked EPDM in a polypropylene (PP) matrix). These normal types include Santoprene 101-80 (cf. example C), which requires an intermediate layer made of a bonding agent material to adhere to polyamide. The Santoprene types which adhere directly to polyamide carry the additional identifier PA after the number, e.g., Santoprene 191-85PA in examples A and B. These adhesion-modified Santoprene-“PA” types preferably contain a certain proportion of polyamide (cf. also
All thermoplastic elastomers come into consideration as components for the sealing strip 11 for vehicle windows according to the invention. In the present invention, under the expression “thermoplastic elastomer” there are understood all thermoplastically processible elastomer compositions, also those which contain cross-linked polymer particles, such as TPV (e.g. Santoprene). The thermoplastic elastomers are preferably selected from a group which comprises TPE-O or TPO (thermoplastic elastomers based on olefin, e.g., EPM or EPDM); TPE-V or TPV (thermoplastic vulcanized rubber comprising a cross-linked rubber in a thermoplastic olefin homopolymer or copolymer, this blend preferably being dynamically vulcanized (dynamically cured), and particularly being the mixture PP/vulcanized (cured) EPDM, e.g., of the Santoprene type); TPE-U or TPU (thermoplastic elastomers based on urethane, e.g., Desmopan); TPE-E or TPC (thermoplastic co-polyester elastomers, e.g., Hytrel); TPE-S or TPS (styrene block copolymers, such as SBS, SEBS, SEPS, SEEPS, and MBS, e.g., Septon) and/or TPE-A or TPA (thermoplastic co-polyamide elastomers, e.g., PEBA). However, PP/vulcanized (cured) EPDM and SEBS are preferred, PP/vulcanized (cured) EPDM being especially preferred.
It is first to be noted on the polyamides (PA) or their nomenclature respectively that they are identified in accordance with the international standard according to the standard ISO 1874-1:1992(E). The standardized spellings for homopolyamides and co-polyamides (the latter with slashes between the component abbreviations) are explained in this standard. In addition, it contains the abbreviations for some monomers, which are abbreviated using letters instead of numbers (e.g., MACM etc.), on the last page. The abbreviation LC stands for lactam: e.g., LC12 means lactam 12, which is the same as laurin lactam. The number indicates the number of carbon atoms of the relevant monomer.
Linear aliphatic polyamides, such as PA 6, PA 66, mixtures made of PA 6 and PA 66, PA 610, PA 612, PA 1010, PA 11, PA 12, and CoPA 6/12 come into consideration as the translucent polyamides, which result in translucent or even transparent layers under suitable processing and/or cooling conditions and/or upon a selection of sufficiently thin layer thicknesses.
Transparent polyamides may be amorphous or microcrystalline. They are synthesized from aliphatic, cycloaliphatic, and/or aromatic monomers and comprise both homopolyamides and also co-polyamides. “Transparent polyamides”, in connection with the present invention, also comprise, in addition to the amorphous polyamides, those polyamides which are no longer completely amorphous, but which are still transparent to the eye because of a microcrystalline structure having crystals which are smaller than the wavelength of light and are thus not visible to the naked eye. Transparent polyamides which are selected from a group which comprises the homopolyamides PA MACM 12, PA PACM 12, PA MACM 14, and PA PACM 14, the co-polyamides PA MACM/PACM 12, PA MACMI/12, PA MACMI/MACMT/12, PA MACM/PACM 14, PA MACM9/109, PA MACM10/1010, PA MACM12/1012, and PA MACM14/1014, and mixtures of the cited polyamides and mixtures with translucent polyamides are preferred. The transparent polyamides selected from the group PA MACM 12 and PA MACMI/MACMT/12 as well as mixtures thereof and mixtures with translucent polyamides are especially preferred. The polyamide PA MACM 12 is available under the trade name Grilamid® TR 90 (as noted above), and a polyamide PA MACMI/MACMT/12 lying in the composition range of Claim 4 is available under the trade name Grilamid® TR 60 from EMS-CHEMIE AG, Domat/Ems, Switzerland.
In connection with the present invention, “effect pigments” are defined as insoluble particles present in a polymer matrix. Depending on their type, size, and current concentration or distribution in a sealing strip according to the invention, such effect pigments at least partially reflect, scatter, or absorb the incident electromagnetic waves (in particular in the visible wavelength range, in the UV or IR and/or NIR ranges) or influence these waves in some way.
Phosphorescent objects are passive illumination systems, as are described per se under the title “Kunststoffe bringen Licht ins Dunkel [Plastics Bring Light into the Dark]” (Walfort & Wettstein; Technische Rundschau 19, 2006) as functional elements, which subsequently luminesce in the dark for hours after activation with light (physical procedure of the luminescence and/or phosphorescence). Luminescent pigments (e.g., based on strontium aluminate) are mixed into luminescent or afterglow plastics. Such phosphorescent plastic layers may (according to the specifications of RC Tritec AG, Teufen, Switzerland, cf. above-mentioned article in Technische Rundschau) be produced having low thicknesses and/or be introduced into an object using co-extrusion or multicomponent injection molding. Exemplary applications cited in the article are, inter alia, door handles, escape route systems, or luminescent covers of hiking water bottles, but no sealing strips and also no specific polymers are disclosed there.
A special variant of the present invention comprises equipping the transparent or translucent polyamide for the second layer of the sealing strip with luminescent pigments. The luminescent layer may be integrated in the sealing strip 11 as the effect layer or in combination with a further effect layer (e.g., cover layer 13 having luminescent pigment and effect layer 17 lying underneath having metallic pigment), the sealing strip preferably being produced by co-extrusion or multi-component injection molding. Application of a luminescent and/or phosphorescent layer using lamination to an already produced second layer 13 and subsequent back-injection of a (possibly adhesion-modified) first elastomer layer 12 underneath is conceivable in spite of the greater work effort. However, during this back-injection process, at least one sliding friction reducing layer 19 may also be bonded to the sealing strip 11 to be produced.
Commercially available additives, such as stabilizers (e.g., heat and UV stabilizers and/or UV absorbers), impact modifiers, softeners, lubricants, coloring agents (colorants, color pigments), effect pigments, reinforcing agents, etc. may be admixed to the polyamides as needed, as long they do not interfere with the visual impression. UV stabilizers (in particular for improving the light stability in externally situated sealing strips), lubricants (for further increasing the scratch resistance), effect pigments (for achieving a high-quality appearance), and luminescent (phosphorescent) colorants and color pigments (for decorative or safety-relevant light effects in the dark) are especially preferred.
All examples listed display good adhesion of the layers to one another. The surface layer made of transparent polyamide is weather resistant and scratch resistant, and the visual appearance is very appealing and decorative, which is also advantageously reinforced by the action of effect, color, and/or metallic pigments and colorants.
Identical reference numerals indicate corresponding components and materials, even if they are not described in detail in every case. Combinations of the embodiments described and/or shown which appear advisable to one skilled in the art are included in the scope of the present invention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2008/056940 | 6/4/2008 | WO | 00 | 2/28/2011 |
