Cushion-like shaped body and use thereof

Abstract

A cushion-like shaped body (1) having an elastic, gel-like filling (2) in a thin-walled outer layer (3) are frequently used as seals, cushions, vibration dampers or shape compensation materials. This shaped body (1) is to be able to withstand severe strains, distortions, compressions and flexural forces, both in the event of brief severe stress and in the event of prolonged stress. For this purpose, the cushion-like shaped body (1) has a filling (2) of a polyurethane having Shore 000 hardness less than or equal to 80 and a compression set less than or equal to 14%, and this filling (2) is present within a shell having an outer layer (3) of a soft silicone material having a layer thickness of 0.075 to 1 mm and a Shore A hardness between 3A and 45A. Such a shaped body (1) is able to return to its original form without lasting elongation after tensile strain at room temperature up to 250%. There is no formation of cracks, detachment phenomena, bubbles, folds or other lasting damage. The elongation does not cause visible detachment between filling (2) and outer layer (3).

Claims

1. A cushion-like shaped body comprising an elastic, gel-like adhesive polyurethane filling in a prefabricated silicone enclosure, wherein the adhesive polyurethane filling fills the enclosure and has an isocyanate index of less than or equal to 80, a Shore (000) hardness of less than or equal to 80, and a compression set of less than or equal to 14%, wherein the adhesive polyurethane filling is a reaction product of a polyisocyanate with a functionality greater than 3 and a polyetherpolyol with a functionality greater than 3 and a hydroxyl value less than 60, wherein the prefabricated silicone enclosure is formed from a soft silicone with a thickness of 0.075 mm to 1 mm, and with a Shore (A) hardness of between 3 A and 45 A, wherein the prefabricated silicone enclosure is highly extensible and highly elastic with an ultimate elongation value of not less than 400% and has a tensile stress at an elongation of 250% of at least 0.5 N/mm.sup.2, wherein an inside surface of the prefabricated silicone enclosure is in direct contact over its full surface area with the adhesive polyurethane filling, wherein an extensibility of the adhesive polyurethane filling is greater than or equal to the extensibility of the prefabricated silicone enclosure, and wherein the cushion-like shaped body reverts with no detachments at an interface of the adhesive polyurethane filling and the inside surface of the prefabricated silicone enclosure to an original shape without undergoing permanent elongation under mechanical loading with a tensile elongation of 250% at room temperature.

2. The cushion-like shaped body as claimed in claim 1, wherein the soft silicone is a liquid silicone rubber (LSR).

3. The cushion-like shaped body as claimed in claim 1, wherein the thickness of the prefabricated silicone enclosure is 0.1 mm to 0.9 mm.

4. The cushion-like shaped body as claimed in claim 3, wherein the thickness of the prefabricated silicone enclosure is 0.1 mm to 0.4 mm.

5. The cushion-like shaped body as claimed in claim 1, wherein the Shore (A) hardness of the prefabricated silicone enclosure is between 5 A and 40 A.

6. The cushion-like shaped body as claimed in claim 5, wherein the Shore (A) hardness of the prefabricated silicone enclosure is between 20 A and 40 A.

7. The cushion-like shaped body as claimed in claim 1, wherein the prefabricated silicone enclosure has an opening that is closed by a sealing or a closure.

8. The cushion-like shaped body as claimed in claim 1, wherein the adhesive polyurethane filling has an isocyanate index of less than or equal to 60.

9. The cushion-like shaped body as claimed in claim 1 wherein the prefabricated silicone enclosure is highly extensible with an ultimate elongation value of at least 500%.

10. A component or article, equipped with the cushion-like shaped body as claimed in claim 1, wherein the component or article is selected from the group consisting of a pad, seal, shape-compensating element, bicycle handle bar grip, saddle, cushion, erotic article, mattress and vibration damper.

11. The component or article as claimed in claim 10, further comprising fastening or holding elements integrally formed, on the prefabricated silicone enclosure.

12. The component or article as claimed in claim 11, wherein fastening or holding elements are molded on the prefabricated silicone enclosure.

Description

DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 shows a stress-strain diagram for extension test piece 3003/05, specimen 1

(3) FIG. 2 shows a stress-strain diagram for extension test piece 3003/10, specimen 2

(4) FIG. 3 shows a stress-strain diagram for extension test piece 3003/40, specimen 3

(5) FIGS. 4-17 show schematic sectional representations and views of various embodiments, specifically:

(6) FIG. 4 a forehead pad of a mask, cross section

(7) FIG. 5 an accident, anesthesia or general respiratory mask, a) in perspective, b) cross section at A-A, c) perspective view with upper mask part

(8) FIG. 6 a lumbar pad

(9) FIG. 7 a head cushion with neck support

(10) FIG. 8 a bicycle saddle

(11) FIG. 9 a head restraint

(12) FIG. 10 a grip

(13) FIG. 11 an armrest

(14) FIGS. 12 and 13 erotic articles

(15) FIG. 14 a mattress

(16) FIG. 15 a vibration damper

(17) FIG. 16 chair upholstery

(18) FIG. 17 a seal, a) in the unloaded state, b) in the sealing state.

DETAILED DESCRIPTION

(19) Tests on Test Pieces

(20) Producing the Test Pieces for the Extension Tests:

(21) A first silicone film is placed onto a planar surface area and a frame with inside dimensions of 100 mm in length, 50 mm in width and 10 mm in height is placed onto the film. This frame is filled with polyurethane gel. A second silicone film is rolled onto the gel. The second silicone film 2 is weighed down with a planar cover. After the full polymerization of the gel, the frame is removed and the protruding silicone film is trimmed. This produces cuboidal test specimens with dimensions of 10050(10.4 to 10.6) mm. The thickness of the first and second silicone films was 0.250.05 mm.

(22) A total of three test pieces were produced by the method described above.

(23) Silicone Material Used for the Extension Test Pieces:

(24) Silicone films of ELASTOSIL from WACKER Chemie AG of three different Shore (A) hardnesses were used. ELASTOSIL 3003/05; Shore A 5 modulus of elasticity 0.12 N/mm.sup.2according to the manufacturer ELASTOSIL 3003/10; Shore A 10 modulus of elasticity 0.13 N/mm.sup.2according to the manufacturer ELASTOSIL 3003/40; Shore A 40 modulus of elasticity 0.20 N/mm.sup.2according to the manufacturer

(25) The silicone films had in each case a thickness of about 0.25 mm.

(26) Gel Used for the Extension Test Pieces:

(27) Polyaddition product of a trifunctional polyether polyol with a hydroxyl value of 30, with a viscosity of 1000 mPas and a tetrafunctional HDI prepolymer with an NCO content of 6% by weight, with a viscosity of 3000 mPas.

(28) The resultant Shore (000) hardness of the gel was 8.

(29) The determination of the Shore hardness is described in ASTM D2240-05 (2010). Equipment and methods are also specified in DIN ISO 868:2003E.

(30) Extension Test Pieces Produced with the Aforementioned Materials:

(31) No. 1 Combination of gel and silicone films of ELASTOSIL 3003/05, hereafter referred to as extension test piece 3003/05 No. 2 Combination of gel and silicone films of ELASTOSIL 3003/10, hereafter referred to as extension test piece 3003/10 No. 3 Combination of gel and silicone films of ELASTOSIL 3003/40, hereafter referred to as extension test piece 3003/40
1. Extension Test

(32) The extension tests were performed on test pieces especially produced for this purpose (extension test pieces). The behavior of the extension test pieces under tensile loading was examined. For this purpose, the test pieces were clamped in a universal testing machine (the Test company).

(33) The distance between the jaws of the testing machine was 90 mm. The specimen was subsequently extended to a length of 360 mm, i.e. the distance traveled was 270 mm and there was an elongation of 300%. The advancement here was 150 mm per minute, the holding time at 300% elongation was 15 seconds, the return rate was 300 mm per minute. In this process, the necessary deflecting stress was determined in relation to the strain and recorded. The associated diagrams can be taken from FIGS. 1 to 3. During the extending process, the behavior of the test piece was observed, in particular the phase transition from gel to silicone skin. The extension of the test pieces was examined once again after the tensile test for possible phase separations. The change in length of the extension test pieces was measured.

(34) Evaluation of the Extension Tests:

(35) A linear dependence of the deflecting stress in relation to the strain (FIGS. 1-3) was found for all the test pieces. With the inclusion of the cross-sectional area of the test pieces, the moduli of elasticity can be derived.

(36) 2. Moduli of Elasticity (Tensile Stress [N/mm.sup.2] at 300% Elongation)

(37) The following moduli of elongation were determined from the extension tests: Extension test piece 3003/05=0.011 N/mm.sup.2=11 kPa Extension test piece 3003/10=0.014 N/mm.sup.2=14 kPa Extension test piece 3003/40=0.054 N/mm.sup.2=54 kPa

(38) Almost no plastic deformation of the test pieces could be found. All of the extension test pieces reverted to their original geometry after the end of the loading. No lasting change in length was found. The very low moduli of elasticity determined characterize the enormous softness of the overall gel-silicone system.

(39) No separation of the gel and silicone film under tensile loading was observed. All of the test pieces had no visual changes during the tensile test and after the end of the loading.

(40) Test Parameters:

(41) distance between clamping jaws 90 mm, clear width advancement 150 mm/min up to a maximum length of 270 mm (300% elongation with respect to the test length) maximum holding time 15 seconds return 300 mm/min.
3. Compression Set

(42) A total of four test pieces were produced for the determination of the compression set (CS), two gel bodies without a coating and two gel bodies with a silicone film coating.

(43) To prepare the gel bodies without a coating, the gel was poured into a polyethylene mold before complete full polymerization and was fully polymerized. This produced a cuboidal gel body with dimensions of length=50 mm, width=50 mm and height=25 mm, which could be removed from the polyethylene mold.

(44) To prepare the gel bodies with a coating, the gel was poured into a prefabricated silicone film. The gel body thus produced was coated with a silicone film on five of six sides after full polymerization. This cuboidal gel body had the dimensions of length=50 mm, width 50 mm and height equal to 25 mm. The only uncoated surface had side lengths of 50 mm50 mm.

(45) Gel Used for CS Test Pieces:

(46) Polyaddition product of a trifunctional polyether polyol with a hydroxyl value of 30, with a viscosity of 1000 mPas and a tetrafunctional HDI prepolymer with an NCO content of 6% by weight, with a viscosity of 3000 mPas.

(47) The resultant Shore (000) hardness of the gel was 8.

(48) Silicone Film Used for the CS Test Pieces:

(49) Prefabricated silicone films of ELASTOSIL 3003/10 with a Shore A hardness of 10 from WACKER Chemie AG were used. For this purpose, silicone films 0.2 to 0.3 mm thick were cast, producing in the filled state a cuboidal body with side lengths of 50 mm, 50 mm and 25 mm. The silicone film thereby formed five faces of a cuboid. The face that is not depicted had side lengths of 50 mm and 50 mm.

(50) CS test pieces produced with the aforementioned materials (gel, silicone): A Gel body 505025 mm (LWH) without coating, hereafter referred to as test piece A B Gel body 505025 mm (LWH) with silicone film coating on five sides, hereafter referred to as test piece B

(51) Two specimens of each of test pieces A and B were produced, referred to as A1, A2, B1, B2.

(52) CS Test:

(53) The compression set of the four test pieces was determined. For this purpose, measurements and evaluations were carried out on the basis of DIN EN ISO 1856:2008-01. The conditions of the ISO standard, Clauses 7.2 and 7.3, are thereby satisfied.

(54) All of test pieces A and B were respectively compressed between two steel plates to 50% of the original height, that is to say to 12.5 mm. One of test pieces A and B respectively were compressed at 25 C., the other two at 70 C., for 22 hours. Subsequently, the height of all four test pieces was determined after 30 minutes, 7 hours and 72 hours. See the following tables.

(55) TABLE-US-00001 A1: test piece A - 25 C. CS [%] - after 30 min CS = 6 CS [%] - after 7 h CS = 6 CS [%] - after 72 h CS = 5

(56) TABLE-US-00002 A2: test piece A - 70 C. CS [%] - after 30 min CS = 13 CS [%] - after 7 h CS = 12 CS [%] - after 72 h CS = 9

(57) TABLE-US-00003 B1: test piece B - 25 C. CS [%] - after 30 min CS = 5 CS [%] - after 7 h CS = 3 CS [%] - after 72 h CS = 1

(58) TABLE-US-00004 B2: test piece B - 70 C. CS [%] - after 30 min CS = 5 CS [%] - after 7 h CS = 5 CS [%] - after 72 h CS = 4

(59) The calculation of the CS was performed in accordance with the formula:
CS=(d.sub.0d.sub.r)/d.sub.0100 d.sub.0=original thickness of the test piece d.sub.r=thickness of the test piece after recovery
Evaluation of the CS Test:

(60) It has surprisingly been found that the in any case already very good recovery of the gel is further improved by the silicone enclosure. The compression set of test pieces B is always better than the compression set of test pieces A.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS OF THE CUSHION

(61) FIG. 4 shows a forehead pad for a mask. The cushion-like shaped body 1 consists of a completely enclosed filling 2, which is in full surface-area contact with the elements enclosing it. These consist of the actual enclosing layer 3 of soft silicone, the fastening elements 34 integrally formed thereon and the plug 32, which closes the opening 30. With the fastening elements 34, the forehead pad is secured to a mask that is not represented here. As a result of its good extensibility and mobility and also compressibility, the forehead pad offers a high degree of wearing comfort. The filling 2 and the enclosing layer 3 behave completely as one. The enclosing layer does not crease or crinkle at any point in time or under any loading.

(62) FIG. 5 shows a further example of an application for the cushion-like shaped body 1 as a seal on a respiratory mask 100. FIG. 5a) shows a perspective view of the seal comprising the shaped body 1, which consists of a soft elastic polyurethane gel body 2 and a soft silicone enclosing layer 3 completely surrounding the gel body. The enclosing layer 3 is closed with a cast plug 33. FIG. 5b) shows a schematic cross-sectional view of the shaped body 1 from FIG. 5a), taken in section at position A-A. In FIG. 5c), the cushion-like shaped body 1 acting as a seal with respect to the user's face sits stably on a respiratory mask shell 4 with a gas exchange attachment 5, both of hard plastic. The sealing cushion 1 is formed as a peripheral lip on the border of the respiratory mask shell 4. In no extension or compression position is the enclosing shell 3 detached from the filling 2; the two move in complete conformity. Even when there are sudden changes in shapeif for example the respiratory mask 100 has to be quickly pressed onto the user's faceno creases or cavities can be formed between the filling 2 and the enclosing layer 3.

(63) FIG. 6 shows a lumbar pad, denoted as a whole by 101. This substantially consists of the cushion-like shaped body 1, which forms the actual pad. The pad in turn consists of the polyurethane gel filling 2 in a silicone enclosing layer 3, which here only partially surrounds the filling 2. The lumbar pad 101 is closed on one side by a hard component 6, which introduces a supporting function. The hard component 6 is formed from hard plastic. By contrast with FIG. 4, where a filling 2 that is enclosed almost completely by the silicone enclosure 3 was shown, here the enclosing layer 3 has a large opening, which is closed with the aid of the hard component 6. The surface area 7 of the filling directly adjoins the hard component 6, so that the filling 2 as a whole is completely enclosed by the enclosing layer 3 and the hard component 6 acting with respect thereto as a base or covering. The component 6 and the enclosing layer 3 together form the enclosure of the filling 2 that is directly in contact with the elastic filling material. A flat cushion is produced, of a very rigid form on one side of the cushion that is facing away from the body of a user.

(64) FIG. 7 shows a cushion 102 in the form of a head cushion with a neck support. The cushion is in turn schematically shown in cross section. The filling of a soft elastic polyurethane gel 2 is completely surrounded by an enclosing layer 3 of silicone. In the case of such a cushion, the filling 2 is relatively thick. Stresses of the filling material and the enclosure 3 may be produced by compressive loading, by extension, but also by twisting or creasing of the cushion. Even under great stresses of this kind, the cushion does not undergo any permanent change. For the production of such a cushion 102, either a dimensionally stable gel body may be produced and completely encapsulated or sprayed with the silicone for the enclosure 3, or the enclosure 3 is produced first, and then has an opening that is not represented in the figure and is subsequently filled with the gel for the filling 2. The silicone enclosure 3 may be subsequently closed with a cast silicone plug.

(65) FIG. 8 shows a bicycle saddle 103, in the case of which the saddle pad consists of the cushion-like shaped body 1, which in turn is made up of the gel filling 2 and the silicone enclosure 3. The silicone enclosing layer 3 completely surrounds the elastic polyurethane filling 2. The cushion body comprising the shaped body 1 is supported by a carrier 8, which can be fastened on a seat post in the usual way with mechanical aids by way of a possibly sprung saddle support.

(66) FIG. 9 shows the cross section of a head restraint, such as may be provided for a motor vehicle seat, an office chair, an armchair, a wheelchair or the like. The head restraint 104 consists of a cushion-like shaped body 1 with the cross section shown and is either fastened to a holder not represented any more specifically here or is adhesively attached to an additional head restraint part (not represented).

(67) FIG. 10 shows a grip 112 comprising the cushion-like shaped body 1 that is fastened to the end of a hard dimensionally stable grip holder 9. The grip holder 9 protrudes into the shaped body 1 and is enclosed by the enclosing layer 3. The filling 2 thereby fills the enclosure comprising the grip holder 9 and the enclosing layer 3 in such a way that the end of the holder is completely encased by the padding filling 2.

(68) FIG. 11 shows an armrest 105, in the case of which the shaped body 1 is formed on a flat rigid carrier 8, in that the filling 2 is completely enclosed by this carrier 8 on the one hand and the enclosure 3 on the other hand. The carrier 8 sits on an adjustable support 10, for example an arm support for an office chair.

(69) FIGS. 12 and 13 show erotic articles. FIG. 12 has a cushion-like shaped body 1 that is elongated in the form of a rod and in this example is completely surrounded by the silicone enclosing layer 3. The shaped body 1 is fastened to a base part 11 by way of the enclosing layer 3. By contrast, the erotic article that is shown in FIG. 13 has a substantially dimensionally stable outer enclosure 12, which stabilizes the shape of the cushion-like shaped body 1 inside this enclosure 12.

(70) FIG. 14 shows a mattress 110, in turn in a schematic cross-sectional view, in which the cushion-like shaped body 1 is formed as a flat overlay on a mattress foam body 13. The shaped body is recessed on one of the surfaces of the foam body 13 and thus finishes flush with the surface of the mattress 110.

(71) FIG. 15 shows a wedge-shaped vibration damper 106, which is arranged between two hard components 6a and 6b, in order to damp vibrations of the hard component 6a that are indicated by arrows.

(72) FIG. 16 shows chair upholstery consisting of a chair seat cushion 107 and a backrest pad 108. Great extensions may occur here, particularly at the front edge of the chair, but cannot cause the seat cushion 107 to lose it shape. In spite of its softness and elasticity, the cushion-like shaped body of the seat cushion 107 and of the backrest pad 108 is in any event dimensionally stable and freely moldable, so that for example the contour of the backrest pad 108 that is represented in the figure is repeatedly resumed.

(73) FIG. 17 shows a schematic diagram of an annular seal, to be precise in the unloaded position in FIG. 17a and in the sealing position in FIG. 17b, here around a cable. The seal consists exclusively of the cushion-like shaped body 1, which is of an annular form here and in the case of which the silicone enclosing layer 3 completely encloses the polyurethane gel of the filling 2. In the unloaded state 16a, the sealing cushion 109 is convexly curved toward the center of the ring and, during sealing, is compressed so as to form a flat ring. As a result of the great mobility of the filling and the enclosure, no leakages can occur. The sealing cushion 109 follows the contour of the cable at every point.

(74) The foregoing description is intended to illustrate the various possibilities for use of the cushion-like shaped body according to the invention. Numerous other applications in which the shaped body may be used as a sealing pad, shape-compensating material and the like can be described.

LIST OF DESIGNATIONS

(75) 1 Cushion-like shaped body 2 Filling of gel 3 Enclosing layer of silicone 4 Respiratory mask shell 5 Gas exchange attachment of a respiratory mask 6 Hard component 7 Surface area 8 Carrier 9 Grip holder 10 Support 11 Base part 12 Outer enclosure 13 Mattress foam body 30 Opening in the silicone enclosure 32 Plug 33 Cast plug 34 Fastening elements 100 Respiratory mask 101 Lumbar pad 102 Cushion 103 Bicycle saddle 104 Head restraint 105 Armrest 106 Vibration damper 107 Chair seat cushion 108 Backrest pad 109 Seal 110 Mattress 111 Erotic article 112 Grip