Durably sealing connection between insert and polymer and 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 TE of the inlay (1, 1′, 1″) is increased (130) at least briefly at least to that temperature TM 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 insert (1, 1′, 1″) and a polymer (3) at least partially enclosing the insert, wherein the insert (1, 1′, 1″) is at least partially electrically conducting or semiconducting, and wherein the insert has a temperature TE, the method comprising: bringing a monomer (2) into contact (110) with the insert (1, 1′, 1″); and subsequently polymerizing (120) the monomer (2) to form the polymer (3), including at least temporarily increasing (130) the temperature TE of the insert (1, 1′, 1″) at least to a temperature T.sub.Max, wherein the temperature T.sub.Max is the maximum temperature the monomer (2) assumes during exothermic polymerization (120) to form the polymer (3), and wherein the at least temporarily increasing (130) the temperature TE of the insert (1, 1′, 1″) at least to the temperature T.sub.Max comprises resistively and/or inductively heating (131) the insert (1, 1′, 1″) by application of a current I.

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

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

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

5. The method (100) as claimed in claim 1, characterized in that the insert (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 insert (1, 1′, 1″) and the polymer (3).

6. A method (200) for producing a sealing integration of an insert (1, 1′, 1″) into a component (5), the method comprising: enclosing the insert (1, 1′, 1″) with a polymer (3) according to the method as claimed in claim 1; and subsequently inserting (210) the insert (1, 1′, 1″) into the component (5).

7. A method (300) for producing a sealing integration of an insert (1, 1′, 1″) into a component (5), the method comprising: introducing (310) the insert (1, 1′, 1″) into a casting mold for production of the component (5); overmolding (320) the insert (1, 1′, 1″) with a plastic (6); and enclosing (100) the insert (1, 1′, 1″) with a polymer (3) as claimed in claim 1, wherein the component (5) is formed from the plastic (6) and the insert (1, 1′, 1″) is connected to the component (5) in a sealing manner.

8. The method (300) as claimed in claim 7, characterized in that the insert (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 overmolding (320).

9. The method (300) as claimed in claim 7, characterized in that the insert (1, 1′, 1″) is enclosed (110) by the monomer (2) before introduction (310) into the casting mold and the temperature of the insert (1, 1′, 1″) is increased at least to T.sub.Max during or after supply (320) of the plastic (6) to polymerize (120) the monomer (2) to form the polymer (3).

10. A method (400) for producing a sealing integration of an insert (1, 1′, 1″) into a component (5), the method comprising: joining the insert (1, 1′, 1″) together (410) with the component (5); and subsequently connecting (100) the insert (1, 1′, 1″) to a polymer (3) according to the method as claimed in claim 1.

11. The method (400) as claimed in claim 10, characterized in that the monomer (2) is brought into contact (110) with the insert via a channel (5c) extending through an interior of the component (5).

12. The method (400) as claimed in claim 10, characterized in that the component (5) is constructed (411) by 3D printing around the insert (1, 1′, 1″), wherein a space (5e) for accommodating the monomer (2) is left free around the insert (1, 1′, 1″), and wherein the monomer (2) is introduced (110) into the space.

13. A method (100) for producing a connection between an insert (1, 1′, 1″) and a polymer (3) at least partially enclosing the insert, wherein the insert (1, 1′, 1″) is at least partially electrically conducting or semiconducting, and wherein the insert has a temperature T.sub.E, the method comprising: bringing a monomer (2) into contact (110) with the insert (1, 1′, 1″); and subsequently polymerizing (120) the monomer (2) to form the polymer (3), including at least temporarily increasing (130) the temperature T.sub.E of the insert (1, 1′, 1″) at least to a temperature that ensures that heat flow always runs from the insert (1, 1′, 1″) to the monomer (2), and wherein the at least temporarily increasing (130) the temperature T.sub.E of the insert (1, 1′, 1″) comprises resistively and/or inductively heating (131) the insert (1, 1′, 1″) by application of a current I.

14. The method (100) as claimed in claim 1, wherein increasing (130) the temperature T.sub.E of the insert (1, 1′, 1″) at least to the temperature T.sub.Max ensures that heat flow always runs from the insert (1, 1′, 1″) to the monomer (2).

15. The method (100) as claimed in claim 1, wherein the method (100) produces an electronic component embedded in a plastic carrier or housed in a plastic housing, and wherein the insert (1, 1′, 1″) at least partially enclosed by the polymer (3) is a metallic electrical feedthrough sealed by a plastic carrier or plastic housing.

16. The method (100) as claimed in claim 15, wherein the electronic component is selected from a conductor track, a sensor, and a printed circuit board.

17. The method (100) as claimed in claim 13, wherein the method (100) produces an electronic component embedded in a plastic carrier or housed in a plastic housing, and wherein the insert (1, 1′, 1″) at least partially enclosed by the polymer (3) is a metallic electrical feedthrough sealed by a plastic carrier or plastic housing.

18. The method (100) as claimed in claim 17, wherein the electronic component is selected from a conductor track, a sensor, and a printed circuit board.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the figures:

(2) FIGS. 1a, 1b and 1c show an exemplary embodiment of the method 100 and a device 50 for carrying it out;

(3) 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.

(4) FIGS. 3a and 3b show an exemplary embodiment of the method 200 having injection 210 of the inlay 1.

(5) FIGS. 4a and 4b show a combination of the method 100 having injection molding in the method 300.

(6) FIG. 5 shows an exemplary embodiment of the method 400 using a component 5 having channel 5c for the monomer 2.

(7) FIGS. 6a and 6b show a modification of the method 400 shown in FIG. 5 having 3D printing 411 of the component 5.

(8) FIG. 7 shows introduction of structures if into the inlay 1 for producing a form-fitting connection to the polymer 3.

DETAILED DESCRIPTION

(9) 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.

(10) 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.

(11) 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.

(12) 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.

(13) FIG. 1b shows the resulting product. Along the contact surface 1a, 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.

(14) 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.

(15) 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.

(16) 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.

(17) 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.

(18) 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.

(19) 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.

(20) 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.

(21) 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.

(22) 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.

(23) 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.

(24) 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.

(25) 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″.

(26) 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.

(27) 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.

(28) 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.

(29) 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.