Form-adaptive upholstery arrangement for seating devices and mattresses

Abstract

The invention relates to a cushioning arrangement (100) as well as a seating device (1000) and a mattress (2000) comprising the cushioning arrangement (100). The cushioning arrangement (100) has a molding layer (10) made of a polyurethane-based material, wherein the polyurethane-based material comprises a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker. Furthermore, a controllable heating element (30) is integrated into the molding layer (10), which is designed to supply thermal energy to the molding layer (10). The cushioning arrangement (100) also has a thermal insulator layer (20) arranged on the molding layer (10) and designed to thermally insulate the molding layer (10).

Description

[0001] The invention relates to a cushion arrangement as well as a seating device and a mattress comprising the cushion arrangement.

[0002] Adjustable upholstery arrangements (upholstery systems) can be found in seating devices such as vehicle seats or treatment chairs, as well as in special mattresses for medical or non-medical treatment beds or stretchers. To meet the individual needs of the driver or patient, a variety of mechanical or electromechanical actuators are used to enable the on-demand adjustment of lumbar support systems, seat positioning, and seat angles. However, actuators require a corresponding control system including electronics, which, in the case of a vehicle seat, for example, places additional demands on the limited installation space and further increases the weight of the vehicle.In addition, the upholstery can only be adapted to the individual physical characteristics of the user to a limited extent and at the same time requires a high level of technical effort, especially in treatment beds for patients with complicated spinal injuries or with diseases that require a demanding lying or sitting position.

[0003] In this respect, non-mechanical solutions, such as the use of shape-memory polymers (SMPs), are becoming the focus of the automotive industry. In this context, patent US 2005 / 0 218 710 A1 discloses a vehicle seat assembly that provides a seat textile with a shape-memory polymer that causes a change in the stiffness and / or flexibility of the seat textile via a thermal activation signal. Depending on the polymer, however, the thermal activation signal can be in a temperature range in which, without adequate thermal insulation, serious tissue damage to the user's skin can occur.

[0004] The invention is based on the object of providing a cushioning arrangement for seating devices and mattresses which can adapt to the individual body shape of the user and which transfers no or at least only a small harmless amount of heat to the user during the adaptation process.

[0005] A first aspect of the present invention relates to a cushioning arrangement. The cushioning arrangement comprises a molding layer, a controllable heating element integrated into the molding layer, and a thermal insulator layer arranged on the molding layer. The molding layer comprises a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker. The controllable heating element is integrated into the molding layer and designed to supply thermal energy to the molding layer (in particular the polyurethane-based material) in order to achieve a switching temperature of the polyurethane-based material. The thermal insulator layer is arranged (directly) on the molding layer and designed to thermally insulate the molding layer (e.g., from the vehicle interior or the contact surface with the user).The furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker are covalently bonded to each other through a temperature-dependent, reversible Diels-Alder reaction. This means that the furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker are covalently bonded (via the functional groups) below a switching temperature and undergo a reversible retro-Diels-Alder reaction above the switching temperature, whereby the covalent bonds between the functional groups are at least partially broken.

[0006] In a preferred embodiment of the invention, it is provided that the maleimide-functionalized crosslinker covalently bonded to the furfuryl alcohol-functionalized polyurethane undergoes a reversible retro-Diels-Alder reaction at a switching temperature in the range of 80 °C to 120 °C.

[0007] In a further preferred embodiment of the invention, it is provided that the thermal insulator layer comprises at least one phase-change material (PCM) which has a phase transition temperature in the range of 20 °C to 60 °C and is suitable for storing at least part of the supplied thermal energy to reach the switching temperature of the polyurethane-based material as latent energy through a phase transition (e.g. solid-liquid, liquid-solid).

[0008] Preferably, the thermal insulator layer comprises at least one phase change material having a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C.

[0009] For this purpose, the thermal insulator layer can preferably comprise at least one phase-change material selected from the following group: unbranched and branched alkanes (paraffins), unsaturated hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, hydrated salts, saturated and unsaturated fatty acids, fatty acid esters, fatty alcohols, anhydrides, ethylene carbonate, polyhydric alcohols, sugar alcohols, and polymers. Phase-change materials selected from unbranched and branched alkanes (paraffins) and hydrated salts are particularly preferred.

[0010] In a preferred embodiment of the invention, the thermal insulator layer comprises a polymer matrix that encloses the previously described phase-change material and is arranged (directly) on the molding layer. In other words, the molding layer is coated on one side (or both sides) with the thermal insulator layer and can thus protect the user from harmful thermal radiation from the controllable heating element.

[0011] The polymer matrix can be a polymer foam, preferably a polyurethane foam. The percentage by weight of the phase-change material relative to the total weight of phase-change material and polymer matrix is ​​preferably 10 to 40 wt.%.

[0012] Preferably, the phase-change material can be present in (micro-)encapsulated form and evenly distributed throughout the thermal insulator layer. In other words, one or more phase-change materials are present in (micro-)encapsulated form and are evenly dispersed in the polymer matrix of the thermal insulator layer, i.e., distributed without forming chemical bonds with the polymer matrix.

[0013] The controllable heating element can be designed as an electrical heating element (e.g., in the form of heating wires, heating coils, heating grids, or the like) and can be integrated (incorporated) into the mold layer or the polyurethane-based material. This enables low heat losses during heat transfer to the polyurethane-based material.

[0014] A second aspect of the present invention relates to a seating device. The seating device comprises a seat surface, a backrest, and can optionally include a headrest. One embodiment of the above-described cushion arrangement is arranged in one or more separate areas of the seat surface.

[0015] Furthermore, an embodiment of the cushion arrangement described above can additionally be arranged in one or more areas of the backrest.

[0016] The seat device may also comprise a control unit configured to activate the controllable heating element of one or more cushion arrangements independently of one another.

[0017] The seating device described above can be designed as a vehicle seat or a (medical) treatment chair.

[0018] Another aspect of the present invention is a mattress wherein an embodiment of the above-described cushioning arrangement is arranged in one or more separate areas of the mattress. The mattress may further comprise a control unit configured to independently activate the controllable heating element of one or more cushioning arrangements.

[0019] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual case.

[0020] The invention is explained below in exemplary embodiments with reference to the accompanying drawings. They show: Fig. 1 a schematic representation of an embodiment of the cushion arrangement, arranged as an example in two areas of a vehicle seat. Fig. 2 a schematic representation of a seating device according to the invention with a seat surface, backrest and headrest as well as an embodiment of the upholstery arrangement according to the invention, which is arranged in several separate areas of the seating device. Fig. 3 a schematic representation of a mattress according to the invention, comprising an embodiment of the cushion arrangement according to the invention, which is arranged in several separate areas of the mattress.

[0021] Fig. 1 shows an embodiment of the cushion assembly 100 in exemplary use, here in a seat device of a vehicle. The cushion assembly 100 comprises a film-like molded layer 10 and a thermal insulator layer 20 arranged on the molded layer. The molded layer 10 is coated at least on one side over its entire surface with the thermal insulator layer 20. As shown in Fig. 1, at least that surface of the molding layer 10 which faces the contact surface of the cushioning arrangement with the user is coated with the thermal insulator layer 20.

[0022] The cushioning arrangement 100 also includes a controllable heating element 30 that is integrated (incorporated) into the molding layer 10 and is designed to supply thermal energy to the molding layer (in particular, the polyurethane-based material). As shown in Fig. As indicated in Figure 1, the controllable heating element 30 can be designed as an electrical heating element in the form of heating wires that are incorporated into the polyurethane-based material and thus in direct contact to enable effective heat transfer to the polyurethane-based material. The controllable heating element 30 is preferably activated and deactivated via a control unit 32, e.g., an electrical switch or controller.

[0023] The thermal insulator layer 20 serves to thermally insulate the mold layer 10 and prevents heat radiation generated by the heating element 30, which is harmful to the user, from reaching the contact surface with the user.

[0024] The cushioning assembly 100 may further comprise a cushioning body that encloses the molding layer 10 and the thermal insulator layer 20. The cushioning assembly 100 may also comprise at least one further cushioning layer arranged on the thermal insulator layer 20. This cushioning layer may comprise conventional cushioning materials, such as polyurethane foam, polyether foam, or polyester foam. The cushioning body, which encloses the molding layer 10, the thermal insulator layer 20, and also the optional cushioning layer, may be covered with a cover made of, for example, a synthetic fabric or leather, on which the user sits or lies directly.

[0025] The mold layer 10 may preferably have a layer thickness of 1 mm to 200 mm.

[0026] The thermal insulator layer 20 may preferably have a layer thickness of 1 mm to 200 mm.

[0027] Fig. 2 shows an embodiment of a seating device 1000 according to the invention. The seating device 1000 has a seat surface 50, a backrest 60, and optionally a headrest 70. As shown, a plurality of cushion assemblies 100 according to the invention can be arranged in several separate areas of the seat surface 50, the backrest 60, and optionally in the headrest 70 and can be controlled via a common control unit 32. The seating device 1000 can also have several control units 32, each of which independently controls one cushion assembly from a plurality of cushion assemblies. In an alternative embodiment of the seating device 1000, the cushion assembly 100 extends continuously from the seat surface 50 across the backrest 60.

[0028] Fig.Figure 3 shows an embodiment of a mattress 2000 according to the invention, in which a plurality of cushion assemblies 100 according to the invention are arranged in several separate areas and controlled via a common control unit 32. Alternatively, a single cushion assembly 100 can be arranged over the entire lying surface of the mattress.

[0029] The mold layer 10 comprises or consists of a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker. The polyurethane-based material preferably has a switching temperature of 80°C to 120°C, particularly preferably of 85°C to 100°C. The switching temperature can be determined by means of differential scanning calorimetry (DSC) during heating cycles from 25°C to 120°C at a heating rate of 10 K / min (e.g., according to DIN EN ISO 11357). The switching temperature is detectable as a change in heat flow in the range between 80 and 120°C.

[0030] In the temperature range below the switching temperature, the maleimide-functionalized crosslinker is covalently bonded to the furfuryl alcohol-functionalized polyurethane via the functional groups (maleimide and furfuryl alcohol), forming a dimensionally stable mold layer. In the temperature range above the switching temperature, the covalent bonds between the maleimide-functionalized crosslinker and the furfuryl alcohol-functionalized polyurethane break, resulting in a flowable (deformable) mold layer. In other words, the maleimide groups react with the furfuryl alcohol groups in a temperature-dependent and reversible [4+2] cycloaddition (reversible Diels-Alder reaction). The switching temperature corresponds to the reaction temperature at which the retro-Diels-Alder reaction (or [4+2] cycloelimination) proceeds, leading to unbound furfuryl alcohol-functionalized polyurethane and maleimide-functionalized crosslinker.If the temperature drops below the switching temperature, the unbound furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker react in a Diels-Alter reaction to form the [4+2] cycloaddition product. The degree of crosslinking of the polyurethane-based material is thus lower above the switching temperature than below it. The molded layer 10 thus becomes reversibly deformable upon heating, allowing the cushioning arrangement to be individually adapted to the user.

[0031] The furfuryl alcohol-functionalized polyurethane is a copolymer made from furfuryl alcohol, at least one polyisocyanate, and at least one polyol. Suitable polyisocyanates include, for example, diisocyanates and triisocyanates. Suitable polyols include, for example, polyether polyols and diols.

[0032] The maleimide-functionalized crosslinker comprises at least two maleimide groups.

[0033] The thermal insulator layer 20 preferably comprises at least one phase-change material (PCM) that has a phase transition temperature in the range of 20°C to 60°C and is suitable for storing at least a portion of the supplied thermal energy to reach the switching temperature of the polyurethane-based material as latent energy through a phase transition (e.g., solid-liquid or liquid-solid, but preferably solid-liquid). The phase transition temperature is preferably in the range of 35°C to 60°C, preferably 40°C to 60°C, particularly preferably 35°C to 58°C. The thermal insulator layer 20 can additionally comprise one or more phase-change materials that have a phase transition temperature in a higher range of 60°C to 130°C, in order to further improve the thermal insulation.

[0034] A phase-change material (PCM) is a substance that requires a high enthalpy of fusion to effect a phase transition, e.g., from a solid to a liquid state. It therefore has the ability to absorb large amounts of thermal energy, known as latent heat, and release it again in a reversible phase transition. During the phase transition, the temperature of the phase-change material remains essentially constant. The phase transition temperature corresponds to the temperature at which the phase transition of the phase-change material begins and latent heat is stored.

[0035] The phase-change material preferably has a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C. The heat storage capacity can be determined using three-layer calorimetry.

[0036] The selection of the phase change material is not limited by its chemical composition, provided that the phase change material has a phase transition temperature in the range of 20 °C to 60 °C and / or a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C. The selection of the optional additional phase change material is also not limited by its chemical composition, provided that it has a phase transition temperature in the range of 60 °C to 130 °C and / or a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 60 °C to 130 °C.

[0037] The phase-change material does not exist as a gas in the temperature range from -20 °C to 500 °C. The phase-change material preferably exists essentially as a solid under normal conditions.

[0038] Examples of phase-change materials include unbranched and branched alkanes (paraffins), unsaturated hydrocarbons (e.g., alkenes, alkynes, and arenes), halogenated hydrocarbons, and alicyclic hydrocarbons. Particularly preferred examples of these classes of substances include n-heneicosane, n-eicosane, n-nonadecane, n-octadecane, and n-heptadecane, as well as mixtures thereof. Another example of a phase-change material is silicone wax.

[0039] Preferred phase-change materials may also include hydrated salts. Suitable hydrated salts include: calcium chloride hexahydrate, calcium bromide hexahydrate, magnesium nitrate hexahydrate, lithium nitrate trihydrate, potassium fluoride tetrahydrate, ammonium alum, magnesium chloride hexahydrate, sodium carbonate decahydrate, disodium phosphate dodecahydrate, sodium sulfate decahydrate, and sodium acetate trihydrate.

[0040] Preferred phase change materials can also include saturated and unsaturated fatty acids, fatty acid esters, and fatty alcohols. Suitable saturated and unsaturated fatty acids include: caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, and cerotic acid. Suitable fatty acid esters include: fatty acid C1-C4 alkyl esters, preferably selected from the group consisting of: methyl caprylate, methyl caprate, methyl laurate, methyl myristate, methyl palmitate, metallic stearate, methyl arachidate, methyl behenate, and methyl lignocerate. Suitable fatty alcohols include: caprylic alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, lignoceryl alcohol, ceryl alcohol, montanyl alcohol, and myricyl alcohol.

[0041] Other examples of phase change materials include anhydrides (e.g. stearic anhydride), ethylene carbonate, polyhydric alcohols (e.g. 2,2-dimethyl-1,3-propanediol, 2-hydroxymethyl-2-methyl-1,3-propanediol, ethylene glycol, polyethylene glycol, pentaerythritol, dipentaerythritol, pentaglycerin, tetramethylol ethane, neopentyl glycol, tetramethylolpropane, 2-amino-2-methyl-1,3-propanediol, monoaminopentaerythritol, diaminopentaerythritol and tris(hydroxymethyl)acetic acid), sugar alcohols (e.g. erythritol, D-mannitol, galactitol, xylitol, D-sorbitol).

[0042] Further examples of phase change materials include polymers selected from the group comprising: polyethylene, polyethylene glycol, polyethylene oxide, polypropylene, polypropylene glycol, polytetramethylene glycol, polypropylene malonate, polyneopentyl glycol sebacate, polypentane glutarate, polyvinyl myristate, polyvinyl stearate, polyvinyl laurate, polyhexadecyl methacrylate and polyoctadecyl methacrylate.

[0043] The thermal insulator layer 20 can preferably comprise one of the following phase change materials from Rubitherm Technologies GmbH: RUBITHERM®RT54HC, RUBITHERM®RT55, and RUBITHERM®SP58. The thermal insulator layer 20 can additionally comprise one or more of the following phase change materials from Rubitherm Technologies GmbH: RUBITHERM®RT62HC, RUBITHERM®RT64HC, RUBITHERM®RT65, RUBITHERM®RT69HC, RUBITHERM®RT70HC, RUBITHERM®RT80HC, RUBITHERM®RT82, RUBITHERM®RT90HC, RUBITHERM®RT100HC, RUBITHERM®RT111HC, and RUBITHERM®RT125. List of reference symbols 100 upholstery arrangement 10 mold layer 20 thermal insulator 30 controllable heating element 32 Control unit 1000 seating device 50 seats 60 backrest 70 Headrest 2000 mattress

Claims

[1] Cushion assembly (100) comprising: a molding layer (10) with a controllable heating element (30) which is integrated into the molding layer (10) and is designed to supply thermal energy to the molding layer (10); and a thermal insulator layer (20) arranged on the mold layer (10) and configured to thermally insulate the mold layer (10); wherein the molding layer (10) comprises a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker, which are covalently bonded to one another by a reversible Diels-Alder reaction in a temperature-dependent manner. [2] The cushioning assembly (100) of claim 1, wherein the maleimide-functionalized crosslinker covalently bonded to the furfuryl alcohol-functionalized polyurethane undergoes a reversible retro-Diels-Alder reaction at a switching temperature in the range of 80°C to 120°C. [3] Cushioning arrangement (100) according to one of claims 1 or 2, wherein the thermal insulator layer (20) comprises at least one phase change material having a phase transition temperature in the range of 20 °C to 60 °C and being suitable for storing at least a portion of the supplied thermal energy for reaching the switching temperature of the polyurethane-based material as latent energy through the phase transition. [4] Cushioning assembly (100) according to any one of the preceding claims, wherein the thermal insulator layer (20) comprises at least one phase change material having a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C. [5] Cushion assembly (100) according to one of the preceding claims, wherein the thermal insulator layer (20) comprises at least one phase change material selected from the group comprising: unbranched and branched alkanes (paraffins), unsaturated hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, hydrated salts, saturated and unsaturated fatty acids, fatty acid esters, fatty alcohols, anhydrides, ethylene carbonate, polyhydric alcohols, sugar alcohols and polymers. [6] The cushioning assembly (100) of any one of claims 3 to 5, wherein the thermal insulator layer (20) comprises a polymer matrix enclosing the phase change material. [7] Cushioning assembly (100) according to claim 6, wherein the phase change material is in encapsulated form uniformly distributed in the thermal insulator layer (20). [8] Seat device (1000) comprising: a seat (50), a backrest (60) and optionally a headrest (70); wherein the cushion arrangement (100) according to one of the preceding claims is arranged in one or more regions of the seat surface (50), the backrest (60) and optionally in the headrest (70). [9] Seat device (1000) according to claim 8, wherein the seat device is a vehicle seat. [10] A mattress (2000), wherein the cushioning arrangement (100) according to any one of claims 1 to 7 is arranged in one or more regions of the mattress (2000).

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