DURABLY SEALING CONNECTION BETWEEN INLAY AND POLYMER PRODUCTION METHOD THEREFOR

Abstract

The invention relates to a method (100) for establishing a connection between an inlay (1, 1, 1) and a polymer (3) at least partially surrounding the inlay, wherein a monomer (2) is brought into contact (110) with the inlay (1, 1, 1) and is subsequently polymerized (120) to form the polymer (3), wherein the temperature T.sub.E of the inlay (1, 1, 1) is increased (130) at least briefly at least to that temperature T.sub.M that the monomer (2) assumes at its maximum during its exothermic polymerization (120) to form the polymer (3), and/or that ensures that the heat flow always runs from the inlay (1, 1, 1) to the monomer (2). The invention also relates to a method (200), (300), (400) for the sealing integration of an inlay (1, 1, 1) in a component (5). The invention also relates to a device (50) for carrying out the method (100), comprising a conveyor (51) for a lead frame (11) in which a multiplicity of inlays (1, 1, 1) are able to be fed, and an at least two-part (52a, 52b) mould (52) which is closable about an individual inlay (1, 1, 1) and has a feed (53) for feeding the monomer (2) into the space (54) between the mould (52) and the inlay (1, 1, 1), wherein a current supply (55) is provided for the resistive and/or inductive heating (131) of the inlay (1, 1, 1) surrounded by the mould (52).

Claims

1. A method (100) for producing a connection between an inlay (1, 1, 1) and a polymer (3) at least partially enclosing the inlay, wherein a monomer (2) is brought into contact (110) with the inlay (1, 1, 1) and is subsequently polymerized (120) to form the polymer (3), characterized in that the temperature T.sub.E of the inlay (1, 1, 1) is at least temporarily increased (130) at least to the temperature T.sub.M which the monomer (2) assumes at most during exothermic polymerization (120) to form the polymer (3) and/or which ensures that the heat flow always runs from the inlay (1, 1, 1) to the monomer (2).

2. The method (100) as claimed in claim 1, characterized in that the temperature T.sub.E of the inlay (1, 1, 1) is kept (140) at or above the temperature T.sub.M at least until the monomer (2) is polymerized (120) at least along a complete contact surface (1a) in relation to the inlay (1, 1, 1).

3. The method (100) as claimed in claim 2, characterized in that the temperature T.sub.E of the inlay (1, 1, 1) is lowered (150) below the temperature T.sub.M after the monomer (2) has been polymerized (120) along the complete contact surface (1a) in relation to the inlay (1, 1, 1).

4. The method (100) as claimed in claim 1, characterized in that the inlay (1, 1, 1) is at least partially electrically conducting or semiconducting.

5. The method (100) as claimed in claim 4, characterized in that the inlay (1, 1, 1) is resistively and/or inductively heated (131) by application of a current I.

6. The method (100) as claimed in claim 1, characterized in that the inlay (1, 1, 1) is immersed (111) in the monomer (2), wherein at least one region (1b) on the a surface (1c) of the inlay (1, 1, 1), which is not to be enclosed by the polymer (3), is covered (112) by a deflector (4).

7. The method (100) as claimed in claim 1, characterized in that the inlay (1, 1, 1) is provided with structures (1f), which, after introduction of the monomer (2) and polymerization (120) of the monomer (2) to form the polymer (3), establish a form-fitting connection between the inlay (1, 1, 1) and the polymer (3).

8. A method (200) for the sealing integration of an inlay (1, 1, 1) into a component (5), characterized in that the inlay (1, 1, 1) is enclosed by a polymer (3) according to the method as claimed in claim 1 and is subsequently injected (210) into the component (5).

9. A method (300) for sealing integration of an inlay (1, 1, 1) into a component (5), characterized in that the inlay (1, 1, 1) is introduced (310) into a casting mold for production of the component (5) and, by way of a combination of extrusion coating (320) using a plastic (6) and enclosing (100) using a polymer (3) as claimed in claim 1, is connected in a sealing manner to the component (5) resulting from the plastic (6).

10. The method (300) as claimed in claim 9, characterized in that the inlay (1, 1, 1) is enclosed (100) by the polymer (3) before introduction (310) into the casting mold and the polymer (3) is partially melted (330) by contact with the plastic during the extrusion coating (320).

11. The method (300) as claimed in claim 9, characterized in that the inlay (1, 1, 1) is enclosed (110) by the monomer (2) before introduction (310) into the casting mold and the temperature of the inlay (1, 1, 1) is increased at least to T.sub.M during or after supply (320) of the plastic (6) to polymerize (120) the monomer (2) to form the polymer (3).

12. A method (400) for sealing integration of an inlay (1, 1, 1) into a component (5), characterized in that the inlay (1, 1, 1) is joined together (410) with the component (5) and is subsequently connected (100) to a polymer (3) according to a method as claimed in claim 1.

13. The method (400) as claimed in claim 12, characterized in that the monomer (2) is brought into contact (110) with the inlay via a channel (5c) extending through an interior of the component (5).

14. The method (400) as claimed in claim 12, characterized in that the component (5) is constructed (411) by 3D printing around the inlay (1, 1, 1), wherein a space (5e) for accommodating the monomer (2) is left free around the inlay (1, 1, 1), and wherein the monomer (2) is introduced (110) into the space.

15. A device (50) for carrying out a method (100) as claimed in claim 1, comprising a conveyor (51) for a stamped grating (11), in which a plurality of inlays (1, 1, 1) can be supplied, and an at least two-part (52a, 52b) mold (52), which is closable around a single inlay (1, 1, 1) and has a supply (53) for the monomer (2) into the space (54) between the mold (52) and the inlay (1, 1, 1), characterized in that a power supply (55) is provided for the resistive and/or inductive heating (131) of the inlay (1, 1, 1) enclosed by the mold (52).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In the figures:

[0039] FIGS. 1a, 1b and 1c show an exemplary embodiment of the method 100 and a device 50 for carrying it out;

[0040] FIGS. 2a, 2b and 2c show an exemplary embodiment of the method 100 with cover 112 of a region 1b on the inlay 1 by a deflector 4.

[0041] FIGS. 3a and 3b show an exemplary embodiment of the method 200 having injection 210 of the inlay 1.

[0042] FIGS. 4a and 4b show a combination of the method 100 having injection molding in the method 300.

[0043] FIG. 5 shows an exemplary embodiment of the method 400 using a component 5 having channel 5c for the monomer 2.

[0044] FIGS. 6a and 6b show a modification of the method 400 shown in FIG. 5 having 3D printing 411 of the component 5.

[0045] FIG. 7 shows introduction of structures if into the inlay 1 for producing a form-fitting connection to the polymer 3.

DETAILED DESCRIPTION

[0046] According to FIG. 1a, the device 50 for carrying out the method 100 comprises a conveyor 51, which conveys a stamped grating 11 having a plurality of inlays 1, 1, 1, formed here as metallic pins, from top to bottom and winds up the grating after delivery of the inlays 51. In FIG. 1a, an inlay 1, which is processed in the present work cycle of the device 50, and a further inlay 1, the processing of which is upcoming in the next work cycle of the device 50, are shown.

[0047] The inlay 1 is introduced into the mold 52, which consists of two parts 52a and 52b. When the two parts 52a and 52b of the mold 52 are closed around the inlay, a space 54 forms between them for accommodating the monomer 2. This space 54 extends peripherally around the inlay 1 and at the same time defines the part 1a of the surface 1c of the inlay 1 which forms the contact surface with the monomer 2. On the left of the space 54, the inlay 1 is clamped between the jaw 52c associated with the part 52a of the mold 52 and the jaw 52d associated with the part 52b of the mold 52. On the right of the space 54, the inlay 1 is clamped between the jaw 52e associated with the part 52a of the mold 52 and the jaw 52f associated with the part 52b of the mold 52.

[0048] In this position, the inlay 1 has contact with the electrodes 55b and 55c, which form the power supply 55 together with a controllable voltage source 55a. Instead of the electrodes 55b and 55c, an inductive power supply 55 can also be used.

[0049] After the monomer 2 has been supplied through the supply 53 in step 110 of the method 100, the inlay 1 is resistively heated by applying a suitable voltage U in step 131. The temperature T.sub.E of the inlay 1 is increased above T.sub.M and step 130 of the method 100 is thus executed. In this way, this in turn has the effect that the monomer 2 polymerizes to form the polymer 3 in step 120 of the method 100.

[0050] FIG. 1b shows the resulting product. Along the contact surface la, which forms a part of the surface 1c of the inlay 1, the inlay 1 is fixedly connected to the polymer 3 resulting from the monomer 2.

[0051] FIG. 1c shows an exemplary curve of the temperature T.sub.E of the inlay 1 over the time t. While the monomer 2 is supplied in step 110 of the method 100, T.sub.E corresponds to the ambient temperature. In step 130, the temperature T.sub.E is increased above T.sub.M. While the temperature T.sub.E is above T.sub.M, the polymerization 120 takes place. According to step 140, the temperature T.sub.E is kept at this level in this exemplary embodiment of the method 100 until the monomer 2 is completely polymerized to form the polymer 3. Subsequently, the temperature T.sub.E is returned back once more to ambient temperature in step 150.

[0052] If the thermal stress is to be minimized for the inlay 1, alternatively the temperature can already be reduced according to step 150 when the monomer 2 is not yet completely polymerized, but rather the resulting polymer 3 just completely covers the contact surface 1a in relation to the inlay 1 for the first time. The temperature T.sub.E is then not reduced down to ambient temperature, but rather to the temperature which is necessary to complete the polymerization 120.

[0053] FIG. 2 shows a further exemplary embodiment of the method 100. According to FIG. 2a, a deflector 4 is firstly placed on the inlay 1 in step 112. When the inlay 1 is subsequently immersed using the heatable gripper 57 in the bath 56, which can be temperature-controlled by the heater 58, having the monomer 2 according to FIG. 2b (step 111), a part 1b of the surface 1c of the inlay 1 is protected from coming into contact with the monomer 2.

[0054] On the contact surface 1a between the monomer 2 and the inlay 1, the monomer 2 polymerizes to form the polymer 3 and forms a fixed coating there. By pulling off the deflector 4 in step 113, the covered region 1b is exposed again. The inlay 1 prepared in this manner can be electrically contacted in each case above and below the region 1a coated with the polymer 3 and can thus be used, for example, as an electrical feedthrough, which is sealed by the polymer 3.

[0055] FIG. 3a schematically illustrates an exemplary embodiment of the method 200 for the sealing integration of the inlay 1 into a component 5. The component 5 has a prepared opening 5b for the inlay 1, which is delimited by a stop 5a. The inlay 1 is firstly connected to the polymer 3 according to the described method 100 and subsequently injected into the opening 5b in step 210 of the method 200.

[0056] FIG. 3b shows the resulting product. Upon encountering the stop 5a in the opening 5b of the component 5, the polymer 3 has deformed to form a seal 3a, which seals the inlay 1 in relation to the component 5. The inlay 1 can thus be used, for example, as an electrical feedthrough through the component 5.

[0057] FIG. 4 illustrates an exemplary embodiment of the method 300, in which the method 100 for connecting three inlays 1, 1, and 1 to the polymer 3 is combined with injection molding. FIG. 4 shows, for the sake of comprehensibility, the state after the solidification of the plastic 6, which forms the component 5, and removal of the injection mold.

[0058] FIG. 4a shows a first variant. In this variant, in step 310 of the method 300, firstly the inlays 1, 1, and 1, each connected to the polymer 3 according to the method 100, were introduced into the casting mold for the component 5. Subsequently, in step 320 of the method 300, the plastic 6 was introduced into the casting mold. Upon solidification of the plastic 6, the component 5 resulted, which encloses in a sealing manner the polymer 3 connected to each of the inlays 1, 1, and 1. In this case, the sealing effect was reinforced in that the polymer 3 was melted on its surface in each case.

[0059] FIG. 4b shows a second variant. In this variant the inlays 1, 1, and 1 were introduced in the state in which they were only coated with monomer 2. The inlays were kept at a temperature between 0 and 50 C. using a cooling 59, to prevent the monomer already melting upon the introduction into the casting mold due to the temperature of the casting mold of approximately 80 C.

[0060] In this variant, the introduction of heat by the hot plastic 6 has also effectuated the polymerization of the monomer 2 to form the polymer 3 visible in FIG. 4b. In order that the monomer 2 was enclosed on all sides either by the inlay 1, 1, 1 or by the hot plastic 6 and was thus converted everywhere to form the polymer 3, the casting mold was modified in such a way that plastic 6 is also located at the points indicated by 6a in FIG. 4b.

[0061] The cooling 59 is very dynamic. Immediately after the pouring in of the hot plastic 6, the temperature T.sub.E of the inlays 1, 1, 1 reaches approximately 30-50 K above T.sub.M. The polymerization of the monomer 2 to form the polymer 3 only during the production of the component 5 by injection molding has the advantage of a still better seal.

[0062] FIG. 5 shows an exemplary embodiment of the method 400, in which three inlays 1, 1, 1 are first joined together with an injection-molded component 5 in step 410 and are subsequently connected to the polymer 3 by the method 100. FIG. 5 shows a snapshot of the point in time at which the monomer 2 is introduced via a supply 53 into the channel 5c. The polymerization can subsequently be started via means (not shown in FIG. 5) for increasing the temperature T.sub.E of the inlays 1, 1, 1.

[0063] FIG. 6 shows a modification of the method 400. In contrast to FIG. 5, the component 5 is produced by layer-by-layer buildup 411 by means of 3D printing on a baseplate 7. A space 5e for the accommodation of the monomer 2 is left free in the component 5 in this case. The inlay 1 is added at a suitable point in time by means of a heatable gripper 57 and subsequently the material of the component 5 is printed around it. Before the space 5e is completely closed, the monomer 2 is introduced into the space 5e via the supply 53.

[0064] FIG. 6a shows a snapshot at a point in time at which the supply 110 of the monomer 2 has just started. At a suitable point in time, by increasing 130 the temperature T.sub.E of the inlay 1 at least to T.sub.M, the polymerization 120 of the monomer 2 to form the polymer 3 can then be started. The 3D printing 411 of the component 5 can be continued while the polymerization 120 is still taking place.

[0065] FIG. 6b shows the resulting final product. The inlay 1 is enclosed by a peripheral ring made of the polymer 3, which is durably sealed in relation to the inlay 1. By the material of the component 5 having in turn been printed around the polymer 3, it is in turn also durably sealed in relation to the component 5. The inlay 1 is therefore overall guided permanently sealed through the wall of the component 5.

[0066] FIG. 7 schematically shows how the inlay 1 can be provided with structures if to improve the adhesion of the polymer 3. The thickness of the polymer 3 and the size of the structures if are shown greatly exaggerated. The polymer 3 engages into the structures if in such a way that a form-fitting connection is produced. The polymer 3 thus can no longer be stripped off from the inlay 1.