Indian Patents. 207128:MOLDING MADE FROM POLYURETHANE AND PROCESS FOR ITS PRODUCTION.

Title of Invention	MOLDING MADE FROM POLYURETHANE AND PROCESS FOR ITS PRODUCTION.
Abstract	A polyurethane molding is composed of at least two different polyurethane materials, namely of a polyurethane gel and a polyurethane foam. The foam and the gel are arranged in layers one above another so that both materials act together as spring or damping element with respect to a load in the transverse direction. These moldings may preferably be used as seat cushions.

Full Text	Molding made from polyurethane and process for its production The invention relates to a molding made from polyurethane, in particular a seat cushion, and a process for its production. The process for producing the molding comprises several alternatives within the framework of a mould casting process. Polyurethanes are used in different morphologies, which have in each case found their areas of application. The use of polyurethane foam is known, for example for upholstered furniture parts, seats, in particular car seats, and for seat cushions. This material, when it is used in the seat field, is employed as a molding or cut from blocks. In the automobile field for example, currently more than 80 % of all cars are fitted with seat cushions made from polyurethane foam. The comfort behavior of these seat cushions is occasionally assessed negatively. Gels made from polyurethane are also known for use as seat cushions. Patent EP 57838 claims gels for avoiding decubitus, which are characterized by a low characteristic, that is by so-called undercuring. They are produced by the reaction of a polyisocyanate with long-chain polyols, which should be free of short-chain portions. These dimensionally stable gels made from polyurethane raw materials may be used as mattresses, mattress inserts, automobile seats and upholstered furniture. Patent EP 511570 protects improved gels made from polyols and polyisocyanates having low characteristic, which are produced from mixtures of long-chain and short-chain polyethers. Cushions in shoes, on bicycle saddles and on seat surfaces, supports to avoid and prevent injuries, face masks and upholstery under riding saddles, may be mentioned, inter alia, as possible applications. The high weight and the high thermal capacity of seat cushions made from pure gel are disadvantageous. The high thermal capacity may lead to a cold seat feeling, since body warmth is removed perceptibly to heat a complete cushion made from gel. 2 The object of the invention now consists in overcoming the afore-mentioned disadvantages in the state of the art and to combine particularly good spring and damping properties of the molding in the load direction with pleasant seat comfort. To achieve this object, the invention provides a molding made from polyurethane which is composed of at least two different polyurethane materials, namely of at least one polyurethane gel and at least one polyurethane foam, which are arranged in at least two different spatial regions of the molding, wherein the materials are joined by the implicit adhesive properties during production of the urethane. According to the invention there is provided a molding made from polyurethane and comprising at least two different polyurethane materials, namely, at least one polyurethane gel and at least one polyurethane foam, which are arranged in at least two different spatial regions of the molding and are joined by the implicit adhesive properties during production of the polyurethane. According to the invention there is also provided a process for producing a molding from polyurethane as described above, which comprises producing in a mould casting, a molding from a polyurethane gel composition and a foamable polyurethane composition, wherein the two compositions are joined to each other during foaming and curing. The molding may be produced in a mould casting process in a conventional mould, as is also used in the production of foam. The bond material integrated in the molding of the invention joins in optimum manner the spring or damping properties of the individual materials, so that a considerable advance with respect to the seat comfort results. Different, for example also multi-layered arrangements of the different materials, are possible. Also regionally different arrangements, wherein for example the one material is arranged only in the region of the seat panel, may advantageously be selected and used depending on the required properties. The molding preferably comprises an outer covering layer which is impermeable particularly to the polyurethane gel. The covering layer may consist of a film, in particular a polyurethane film, a polyvinyl chloride film or leather or a textile material, such as for example a microfibre material. In principle, various flexible materials are suitable as film material. In a preferred embodiment of the invention, the polyurethane foam and the polyurethane gel are arranged in at least two layers one above another, so that the foam 3 and the gel layered one above another act overall as spring or damping element with respect to a load in the transverse direction. In individual exemplary embodiments, a gel layer may be surrounded at least partly by foam or a foam block may be surrounded at least partly by a gel. In a further development of the invention, the molding is designed as a seat cushion, wherein a textile cover layer is additionally present preferably at least on the side on the seat panel side. This applies particularly when a film has been used during rear-foaming. In this case, the cushion is conventionally covered later. If textiles are used externally in this embodiment of the invention, they should be sealed to be vacuum-tight towards the gel side. The use of a textile cover material directly as a covering layer is therefore not possible for simple, coarser textiles, since penetration of the still liquid gel material into the textile should be prevented. Films made from thermoplastic polyurethane or closed-cell, cut polyurethane foam, may be used by way of example for depositing a textile covering material. The conventional polyols and polyisocyanates are reacted with one another to produce the polyurethane foam. The processing technology and the typical raw materials can be found, for example in the "Polyurethane Handbook", published by G. Oertel. Raw materials, as described in European patents EP 57838 and EP 511570, may be used for producing the gels. The process for producing a molding made from polyurethane according to the invention is characterized in that in a mould casting process, a molding made from a polyurethane gel composition and a foamable polyurethane reaction mixture is produced, wherein the two compositions are joined to one another during foaming and curing. The fact that the sandwich construction of two different polyurethanes utilizes the adhesive properties of this material in optimum manner, has a particularly advantageous effect on the molding produced. 4 The materials are preferably cast onto a covering layer, which has been laid in the mould die, or the covering layer is placed on the final bond material. If required, the moldings produced may then also be covered with a further material. In one embodiment, the process may be carried out so that a freshly produced mixture of polyol and polyisocyanate as gel composition is introduced into a mould lined with a covering layer, that a polyurethane raw material mixture is then applied to the gel layer for the production of foam, and that conditions for foaming and curing of the compositions are maintained in the mould. According to a further embodiment of the process, a preformed gel layer may be introduced into the mould preferably lined with an outer covering layer, after which a polyurethane raw material mixture is applied for the production of foam and then conditions for foaming and curing of the molding are maintained in conventional manner- that is a certain residence time with a certain temperature profile. The preformed gel layer may, for example either be placed on the mould base or attached to the mould lid. In a further alternative embodiment, a preformed foam block may also be placed in the mould, after which the mould is filled with a gel composition and the reaction conditions for producing the polyurethane gel from the gel composition are maintained. The polyurethane gel is preferably produced from raw materials, wherein the product of the isocyanate functionality and the functionality of the polyol component is at least 5.2, preferably at least 6.5, also preferably at least 7.5. In preferred embodiments, the polyol component for producing the gel consists of a mixture of one or more polyols having hydroxyl numbers below 112, and one or more polyols having hydroxyl numbers in the range 112 to 600, wherein the weight ratio of component a) to component b) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to 5 59.81, and the product of the isocyanate functionality and functionality of the polyol component is at least 6.15. In a further specific exemplary embodiment, the raw materials for producing the gel consists of one or more polyisocyanates, and a polyol component consisting of one of more polyols (b1) having hydroxyl numbers below 112, and one or more polyols (b2) having hydroxyl numbers in the range 112 to 600, and optionally a catalyst for the reaction between isocyanate and hydroxyl groups, and optionally fillers and/or additives known per se from polyurethane chemistry, wherein the weight ratio of component (b1) to component (b2) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to 59.81, and the product of the isocyanate functionality and the functionality of the polyol component is at least 6.15. The polyol component for producing the gel preferably consists of one or more polyols having a molecular weight between 1,000 and 12,000 and an OH number between 20 and 112, wherein the product of the functionalities of the polyurethane-forming components is at least 5.2, and the isocyanate characteristic lies between 15 and 60. As isocyanates for gel production, those of the formula Q(NCO)n may preferably be used, wherein n represents 2 to 4 and Q denotes an aliphatic hydrocarbon radical having 8 to 18 C atoms, a cycloaliphatic hydrocarbon radical having 4 to 15 C atoms, an aromatic hydrocarbon radical having 8 to 15 C atoms. The isocyanates may be used in pure form or in the form of the conventional isocyanate modifications, such as urethanisation, allophantisation or biuretisation. The invention is described in more detail below using exemplary embodiments, which should better explain the possible embodiments. In one embodiment of the invention, a film or a textile, which is provided with a vacuum-tight film, is deep-drawn in a seat mould. The underside of the mould later represents the seat panel of the cushion. A freshly produced mixture of polyol and polyisocyanate is then introduced in liquid form into this mould. These gel starting 6 materials completely or partly cover the seat panel after filling. After this mixture has reacted completely or partly to form a polyurethane gel, in the next step a liquid or pre-foamed mixture of polyurethane raw materials is introduced into the mould for the production of mould foam. The mixture foams, the lid of the mould is closed and after the curing time of conventionally between one to 10 minutes, the complete seat cushion is removed from the mould. In a further embodiment of the invention, the polyurethane gel is produced separately and placed in the mould as a dimensionally stable gel in one piece or in sections. The gel is positioned on the film or on the laminated textile. After foaming in the mould, the gel is fixed at defined points of the seat panel by the polyurethane foam. Hence, the gel may specifically improve the comfort. In this embodiment, it is also possible to position a gel cushion on the mould lid. It is thus situated at the bottom after foaming. The seated feeling in a foam can thus advantageously be combined with the pressure-distributing properties of the polyurethane gel. In a third embodiment of this invention, cut polyurethane foam and the gel are joined to one another by the reacting gel. This takes place for example in that the gel is cast onto a deep-drawn film or a vacuum-tight textile, and then the foam is placed on the incompletely reacted gel. The intimate bond of gel and foam is produced during the completion reaction. 7 We claim 1. Molding made from polyurethane and comprising at least two different polyurethane materials, namely, at least one polyurethane gel and at least one polyurethane foam, which are arranged in at least two different spatial regions of the molding and are joined by the implicit adhesive properties during production of the polyurethane. 2. Molding as claimed in claim 1, which comprises an outer covering layer which is impermeable particularly to the polyurethane gel. 3. Molding as claimed in claim 1 or 2, wherein the polyurethane foam and the polyurethane gel are arranged in at least two layers one above the other. 4. Molding as claimed in any one of claims 1 to 3, wherein the polyurathane gel is surrounded at least partly by the polyurethane foam or a block of the polyurethane foam is surrounded at least partly by the polyurethane gel. 5. Molding as claimed in any one of claims 2 to 4, wherein the outer covering layer consists of a film, in particular a polyurethane film, a polyvinyl chloride film or a textile material, in particular a microfibre material. 6. Molding as claimed in any one of claims 1 to 5, wherein the molding is a seat cushion. 7. Molding as claimed in claim 6, wherein the seat cushion comprises a textile material cover layer on the seat panel side thereof. 8. Process for producing a molding from polyurethane as claimed in any one of claims 1 to 7, which comprises producing in a mould casting, a molding from a polyurethane gel composition and a foamable polyurethane composition, wherein the two compositions are joined to each other during foaming and curing. 8 9. Process as claimed in claim 8, wherein the polyurathane gel composition and foamable polyurethane composition are cast onto a covering layer, preferably a film or a covering layer is placed on the polyurethane gel composition and foamable polyurethane composition. 10. Process as claimed in claim 8 or 9, wherein a freshly produced mixture of polyol and polyisocyanate as the gel composition is introduced into a mould lined with a covering layer and a polyurethane raw material mixture as the foamable composition is then applied to the gel composition for production of foam under conditions for foaming and curing of the compositions maintained in the mould. 11. Process as claimed in claim 8 or 9, wherein a preformed gel composition is introduced into the mould preferably lined with a covering layer and a polyurethane raw material mixture as foamable composition is then applied for the production of foam under conditions for foaming and curing of the compositions maintained in the mould. 12. Process as claimed in claim 11, wherein the preformed gel composition is placed on the mould base or attached to the mould lid. 13. Process as claimed in claim 8 or 9, wherein a performed foam block as the foamable composition is placed in the mould and the mould is filled with the gel composition and reaction conditions for producing the polyurethane from the gel composition are maintained in the mould. 14. Process as claimed in any one of claims 8 to 13, wherein the gel composition is produced using raw materials, wherein the product of the isocyanate functionality and the functionality of the polyol component is at least 5.2, preferably 6.5, in particular at least 7.5. 15. Process as claimed in any one of claims 8 to 13, wherein the polyol component for producing the gel consists of a mixture of (a) one or more polyols having hydroxyl numbers below 112, and (b) one or more polyols having hydroxyl numbers in the range 112 to 600, 9 wherein the weight ratio of component a) to component b) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to 59.81, and the product of isocyanate functionality and functionality of the polyol component is at least 6.15. 16. Process as claimed in any one of claims 8 to 13, wherein the raw materials for producing the gel composition consist of one or more polyisocyanates, and a polyol component consisting of one or more polyols (b1) having hydroxyl numbers below 112, and one or more polyols (b2) having hydroxyl numbers in the range 112 to 600, and optionally a catalyst for the reaction between isocyanate and hydroxyl groups, and optionally fillers and/or additives known per se from polyurethane chemistry, wherein the weight ratio of component (b1) to component (b2) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lie in the range from 15 to 59.81, and the product of the isocyanate functionality and the functionality of the polyol component is at least 6.15. 17. Process as claimed in any one of claims 8 to 16, wherein the polyol component for producing the gel composition consists of one or more polyols having a molecular weight between 1,000 and 12,000 and an OH number between 20 and 112, wherein the product of the functionalities of the polyurethane-forming components is at least 5.2, and the isocyanate characteristic lies between 15 and 60. 18. Process as claimed in any one of claims 8 to 17, wherein as isocyanates for gel production those of the formula Q(NCO)n are used, in which n represents 2 to 4 and Q denotes an aliphatic hydrocarbon radical having 8 to 18 C atoms, a cycloaliphatic hydrocarbon radical having 4 10 11 to 15 C atoms, an aromatic hydrocarbon radical having 6 to 15 C atoms, or an aliphatic hydrocarbon radical having 8 to 15 C atoms, the isocyanates used being in pure form or in the form of the conventional isocyanate modifications such as urethanisation, allophantisation or biuretisation. A polyurethane molding is composed of at least two different polyurethane materials, namely of a polyurethane gel and a polyurethane foam. The foam and the gel are arranged in layers one above another so that both materials act together as spring or damping element with respect to a load in the transverse direction. These moldings may preferably be used as seat cushions.

Full Text

Molding made from polyurethane and process for its production
The invention relates to a molding made from polyurethane, in particular a seat cushion, and a process for its production. The process for producing the molding comprises several alternatives within the framework of a mould casting process.
Polyurethanes are used in different morphologies, which have in each case found their areas of application. The use of polyurethane foam is known, for example for upholstered furniture parts, seats, in particular car seats, and for seat cushions. This material, when it is used in the seat field, is employed as a molding or cut from blocks.
In the automobile field for example, currently more than 80 % of all cars are fitted with seat cushions made from polyurethane foam. The comfort behavior of these seat cushions is occasionally assessed negatively.
Gels made from polyurethane are also known for use as seat cushions.
Patent EP 57838 claims gels for avoiding decubitus, which are characterized by a low characteristic, that is by so-called undercuring. They are produced by the reaction of a polyisocyanate with long-chain polyols, which should be free of short-chain portions. These dimensionally stable gels made from polyurethane raw materials may be used as mattresses, mattress inserts, automobile seats and upholstered furniture.
Patent EP 511570 protects improved gels made from polyols and polyisocyanates having low characteristic, which are produced from mixtures of long-chain and short-chain polyethers. Cushions in shoes, on bicycle saddles and on seat surfaces, supports to avoid and prevent injuries, face masks and upholstery under riding saddles, may be mentioned, inter alia, as possible applications.
The high weight and the high thermal capacity of seat cushions made from pure gel are disadvantageous. The high thermal capacity may lead to a cold seat feeling, since body warmth is removed perceptibly to heat a complete cushion made from gel.
2

The object of the invention now consists in overcoming the afore-mentioned disadvantages in the state of the art and to combine particularly good spring and damping properties of the molding in the load direction with pleasant seat comfort.
To achieve this object, the invention provides a molding made from polyurethane which is composed of at least two different polyurethane materials, namely of at least one polyurethane gel and at least one polyurethane foam, which are arranged in at least two different spatial regions of the molding, wherein the materials are joined by the implicit adhesive properties during production of the urethane.
According to the invention there is provided a molding made from polyurethane and comprising at least two different polyurethane materials, namely, at least one polyurethane gel and at least one polyurethane foam, which are arranged in at least two different spatial regions of the molding and are joined by the implicit adhesive properties during production of the polyurethane.
According to the invention there is also provided a process for producing a molding from polyurethane as described above, which comprises producing in a mould casting, a molding from a polyurethane gel composition and a foamable polyurethane composition, wherein the two compositions are joined to each other during foaming and curing.
The molding may be produced in a mould casting process in a conventional mould, as is also used in the production of foam. The bond material integrated in the molding of the invention joins in optimum manner the spring or damping properties of the individual materials, so that a considerable advance with respect to the seat comfort results. Different, for example also multi-layered arrangements of the different materials, are possible. Also regionally different arrangements, wherein for example the one material is arranged only in the region of the seat panel, may advantageously be selected and used depending on the required properties.
The molding preferably comprises an outer covering layer which is impermeable particularly to the polyurethane gel.
The covering layer may consist of a film, in particular a polyurethane film, a polyvinyl chloride film or leather or a textile material, such as for example a microfibre material. In principle, various flexible materials are suitable as film material.
In a preferred embodiment of the invention, the polyurethane foam and the polyurethane
gel are arranged in at least two layers one above another, so that the foam
3

and the gel layered one above another act overall as spring or damping element with respect to a load in the transverse direction.
In individual exemplary embodiments, a gel layer may be surrounded at least partly by foam or a foam block may be surrounded at least partly by a gel.
In a further development of the invention, the molding is designed as a seat cushion, wherein a textile cover layer is additionally present preferably at least on the side on the seat panel side. This applies particularly when a film has been used during rear-foaming. In this case, the cushion is conventionally covered later.
If textiles are used externally in this embodiment of the invention, they should be sealed to be vacuum-tight towards the gel side. The use of a textile cover material directly as a covering layer is therefore not possible for simple, coarser textiles, since penetration of the still liquid gel material into the textile should be prevented. Films made from thermoplastic polyurethane or closed-cell, cut polyurethane foam, may be used by way of example for depositing a textile covering material.
The conventional polyols and polyisocyanates are reacted with one another to produce the polyurethane foam. The processing technology and the typical raw materials can be found, for example in the "Polyurethane Handbook", published by G. Oertel.
Raw materials, as described in European patents EP 57838 and EP 511570, may be used for producing the gels.
The process for producing a molding made from polyurethane according to the invention is characterized in that in a mould casting process, a molding made from a polyurethane gel composition and a foamable polyurethane reaction mixture is produced, wherein the two compositions are joined to one another during foaming and curing.
The fact that the sandwich construction of two different polyurethanes utilizes the adhesive properties of this material in optimum manner, has a particularly advantageous effect on the molding produced.
4

The materials are preferably cast onto a covering layer, which has been laid in the mould die, or the covering layer is placed on the final bond material.
If required, the moldings produced may then also be covered with a further material.
In one embodiment, the process may be carried out so that a freshly produced mixture of polyol and polyisocyanate as gel composition is introduced into a mould lined with a covering layer, that a polyurethane raw material mixture is then applied to the gel layer for the production of foam, and that conditions for foaming and curing of the compositions are maintained in the mould.
According to a further embodiment of the process, a preformed gel layer may be introduced into the mould preferably lined with an outer covering layer, after which a polyurethane raw material mixture is applied for the production of foam and then conditions for foaming and curing of the molding are maintained in conventional manner- that is a certain residence time with a certain temperature profile.
The preformed gel layer may, for example either be placed on the mould base or attached to the mould lid.
In a further alternative embodiment, a preformed foam block may also be placed in the mould, after which the mould is filled with a gel composition and the reaction conditions for producing the polyurethane gel from the gel composition are maintained.
The polyurethane gel is preferably produced from raw materials, wherein the product of the isocyanate functionality and the functionality of the polyol component is at least 5.2, preferably at least 6.5, also preferably at least 7.5.
In preferred embodiments, the polyol component for producing the gel consists of a
mixture of
one or more polyols having hydroxyl numbers below 112, and
one or more polyols having hydroxyl numbers in the range 112 to 600,
wherein the weight ratio of component a) to component b) lies between 90:10 and
10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to
5

59.81, and the product of the isocyanate functionality and functionality of the polyol component is at least 6.15.
In a further specific exemplary embodiment, the raw materials for producing the gel
consists of
one or more polyisocyanates, and
a polyol component consisting of
one of more polyols (b1) having hydroxyl numbers below 112, and
one or more polyols (b2) having hydroxyl numbers in the range 112 to 600, and
optionally a catalyst for the reaction between isocyanate and hydroxyl groups, and
optionally fillers and/or additives known per se from polyurethane chemistry, wherein
the weight ratio of component (b1) to component (b2) lies between 90:10 and
10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to
59.81, and the product of the isocyanate functionality and the functionality of the
polyol component is at least 6.15.
The polyol component for producing the gel preferably consists of one or more polyols having a molecular weight between 1,000 and 12,000 and an OH number between 20 and 112, wherein the product of the functionalities of the polyurethane-forming components is at least 5.2, and the isocyanate characteristic lies between 15 and 60.
As isocyanates for gel production, those of the formula Q(NCO)n may preferably be used, wherein n represents 2 to 4 and Q denotes an aliphatic hydrocarbon radical having 8 to 18 C atoms, a cycloaliphatic hydrocarbon radical having 4 to 15 C atoms, an aromatic hydrocarbon radical having 8 to 15 C atoms. The isocyanates may be used in pure form or in the form of the conventional isocyanate modifications, such as urethanisation, allophantisation or biuretisation.
The invention is described in more detail below using exemplary embodiments, which should better explain the possible embodiments.
In one embodiment of the invention, a film or a textile, which is provided with a vacuum-tight film, is deep-drawn in a seat mould. The underside of the mould later represents the seat panel of the cushion. A freshly produced mixture of polyol and polyisocyanate is then introduced in liquid form into this mould. These gel starting
6

materials completely or partly cover the seat panel after filling. After this mixture has reacted completely or partly to form a polyurethane gel, in the next step a liquid or pre-foamed mixture of polyurethane raw materials is introduced into the mould for the production of mould foam. The mixture foams, the lid of the mould is closed and after the curing time of conventionally between one to 10 minutes, the complete seat cushion is removed from the mould.
In a further embodiment of the invention, the polyurethane gel is produced separately and placed in the mould as a dimensionally stable gel in one piece or in sections. The gel is positioned on the film or on the laminated textile. After foaming in the mould, the gel is fixed at defined points of the seat panel by the polyurethane foam. Hence, the gel may specifically improve the comfort. In this embodiment, it is also possible to position a gel cushion on the mould lid. It is thus situated at the bottom after foaming. The seated feeling in a foam can thus advantageously be combined with the pressure-distributing properties of the polyurethane gel.
In a third embodiment of this invention, cut polyurethane foam and the gel are joined to one another by the reacting gel. This takes place for example in that the gel is cast onto a deep-drawn film or a vacuum-tight textile, and then the foam is placed on the incompletely reacted gel. The intimate bond of gel and foam is produced during the completion reaction.
7

We claim
1. Molding made from polyurethane and comprising at least two different
polyurethane materials, namely, at least one polyurethane gel and at least one
polyurethane foam, which are arranged in at least two different spatial regions
of the molding and are joined by the implicit adhesive properties during
production of the polyurethane.
2. Molding as claimed in claim 1, which comprises an outer covering layer
which is impermeable particularly to the polyurethane gel.
3. Molding as claimed in claim 1 or 2, wherein the polyurethane foam and the
polyurethane gel are arranged in at least two layers one above the other.
4. Molding as claimed in any one of claims 1 to 3, wherein the polyurathane gel
is surrounded at least partly by the polyurethane foam or a block of the
polyurethane foam is surrounded at least partly by the polyurethane gel.
5. Molding as claimed in any one of claims 2 to 4, wherein the outer covering
layer consists of a film, in particular a polyurethane film, a polyvinyl chloride
film or a textile material, in particular a microfibre material.
6. Molding as claimed in any one of claims 1 to 5, wherein the molding is a seat
cushion.
7. Molding as claimed in claim 6, wherein the seat cushion comprises a textile
material cover layer on the seat panel side thereof.
8. Process for producing a molding from polyurethane as claimed in any one of
claims 1 to 7, which comprises producing in a mould casting, a molding from
a polyurethane gel composition and a foamable polyurethane composition,
wherein the two compositions are joined to each other during foaming and
curing.
8

9. Process as claimed in claim 8, wherein the polyurathane gel composition and
foamable polyurethane composition are cast onto a covering layer, preferably
a film or a covering layer is placed on the polyurethane gel composition and
foamable polyurethane composition.
10. Process as claimed in claim 8 or 9, wherein a freshly produced mixture of
polyol and polyisocyanate as the gel composition is introduced into a mould
lined with a covering layer and a polyurethane raw material mixture as the
foamable composition is then applied to the gel composition for production of
foam under conditions for foaming and curing of the compositions maintained
in the mould.
11. Process as claimed in claim 8 or 9, wherein a preformed gel composition is
introduced into the mould preferably lined with a covering layer and a
polyurethane raw material mixture as foamable composition is then applied for
the production of foam under conditions for foaming and curing of the
compositions maintained in the mould.
12. Process as claimed in claim 11, wherein the preformed gel composition is
placed on the mould base or attached to the mould lid.
13. Process as claimed in claim 8 or 9, wherein a performed foam block as the
foamable composition is placed in the mould and the mould is filled with the
gel composition and reaction conditions for producing the polyurethane from
the gel composition are maintained in the mould.
14. Process as claimed in any one of claims 8 to 13, wherein the gel composition
is produced using raw materials, wherein the product of the isocyanate
functionality and the functionality of the polyol component is at least 5.2,
preferably 6.5, in particular at least 7.5.
15. Process as claimed in any one of claims 8 to 13, wherein the polyol component
for producing the gel consists of a mixture of

(a) one or more polyols having hydroxyl numbers below 112, and
(b) one or more polyols having hydroxyl numbers in the range 112 to 600,
9

wherein the weight ratio of component a) to component b) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lies in the range from 15 to 59.81, and the product of isocyanate functionality and functionality of the polyol component is at least 6.15.
16. Process as claimed in any one of claims 8 to 13, wherein the raw materials for producing the gel composition consist of one or more polyisocyanates, and a polyol component consisting of one or more polyols (b1) having hydroxyl numbers below 112, and one or more polyols (b2) having hydroxyl numbers in the range 112 to 600, and optionally a catalyst for the reaction between isocyanate and hydroxyl groups, and optionally fillers and/or additives known per se from polyurethane chemistry, wherein the weight ratio of component (b1) to component (b2) lies between 90:10 and 10:90, the isocyanate characteristic of the reaction mixture lie in the range from 15 to 59.81, and the product of the isocyanate functionality and the functionality of the polyol component is at least 6.15.
17. Process as claimed in any one of claims 8 to 16, wherein the polyol component for producing the gel composition consists of one or more polyols having a molecular weight between 1,000 and 12,000 and an OH number between 20 and 112, wherein the product of the functionalities of the polyurethane-forming components is at least 5.2, and the isocyanate characteristic lies between 15 and 60.
18. Process as claimed in any one of claims 8 to 17, wherein as isocyanates for gel production those of the formula
Q(NCO)n
are used, in which n represents 2 to 4 and Q denotes an aliphatic hydrocarbon
radical having 8 to 18 C atoms, a cycloaliphatic hydrocarbon radical having 4
10

11
to 15 C atoms, an aromatic hydrocarbon radical having 6 to 15 C atoms, or an aliphatic hydrocarbon radical having 8 to 15 C atoms, the isocyanates used being in pure form or in the form of the conventional isocyanate modifications such as urethanisation, allophantisation or biuretisation.
A polyurethane molding is composed of at least two different polyurethane materials, namely of a polyurethane gel and a polyurethane foam. The foam and the gel are arranged in layers one above another so that both materials act together as spring or damping element with respect to a load in the transverse direction. These moldings may preferably be used as seat cushions.

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Patent Number

207128

Indian Patent Application Number

00618/CAL/2000

PG Journal Number

21/2007

Publication Date

25-May-2007

Grant Date

23-May-2007

Date of Filing

06-Nov-2000

Name of Patentee

TECHNOGEL GMBH & CO. KG

Applicant Address

MAX-NAEDER-STRASSE 15, D-37115 DUDERSTADT,

Inventors:

#	Inventor's Name	Inventor's Address
1	GANSEN PETER	AM STEINBERG 49 D-37136 SEEBURG,
2	LOSIO MASSIMO	2, AVENUE DE CITRONIERE MC-98011 MONACO,

PCT International Classification Number

B32B 5/32

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	19957397.2	1999-11-29	Germany