Title of Invention	AN EXTRUDED , INJECTION MOULDED OR BLOW MOULDED PLASTIC PIPE AND A METHOD OF PRODUCING A COMPOSITE MATERIAL
Abstract	The extruded, injection-moulded or blow-moulded plastic pipe for creating pipelines, with a pipe body (1) made up of at least three layers, is characterized in that the inner layer (2) and the middle layer (4) consist of a polymer material, in that additives against aggressive media, in particular oxidizing and reducing media, are incorporated into the amorphous regions of the semicrystalline polymer material of the inner layer (2) in contact with the medium to be transported and/or the middle layer (4), and in that fillers and/or additives are incorporated into the amorphous regions of the polymer material of the middle layer (4) as barrier materials to reduce migration of the additives from the inner layer (2) into the outer layer (3) of the pipe.

Title of Invention

AN EXTRUDED , INJECTION MOULDED OR BLOW MOULDED PLASTIC PIPE AND A METHOD OF PRODUCING A COMPOSITE MATERIAL

Abstract

The extruded, injection-moulded or blow-moulded plastic pipe for creating pipelines, with a pipe body (1) made up of at least three layers, is characterized in that the inner layer (2) and the middle layer (4) consist of a polymer material, in that additives against aggressive media, in particular oxidizing and reducing media, are incorporated into the amorphous regions of the semicrystalline polymer material of the inner layer (2) in contact with the medium to be transported and/or the middle layer (4), and in that fillers and/or additives are incorporated into the amorphous regions of the polymer material of the middle layer (4) as barrier materials to reduce migration of the additives from the inner layer (2) into the outer layer (3) of the pipe.

Full Text	Description Title: Extruded, injection-moulded or blow-moulded pipe, fitting or shaped part made of plastic for creating pipelines for liquid, pasty and gaseous media The invention relates to an extruded, injection-moulded or blow-moulded pipe, fitting or shaped part made of plastic for creating pipelines for liquid, pasty and gaseous media, with a pipe body made up of at least three layers, with an inner layer and an outer layer of a base material and a middle layer of a base material and at least one additional material (EP 0 470 605 Al). The application areas for pipes made of metal, in particular copper, galvanized steel, high-grade steel and to a lesser extent lead, are restricted by certain media parameters such as the pH, flow rate and operating temperature. The corrosion behaviour of metal pipes and the release of heavy metals in the case of lead and copper pipes further restrict the possible applications of metal pipes for drinking water lines and lines required in the food industry. Added to this is the fact that in many cases the extraction of metals, the mining and transporting of ores and the smelting of ores as well as the production of metal pipes is no longer economical on account of the required expenditure of energy and is no longer justifiable with regard to environmental damage. For the reasons mentioned above, plastic pipes are gaining increasingly in significance for the creation of pipelines for various application areas, such as the supply of drinking water, heating engineering, the food industry, apparatus construction and the chemical industry. The advantages of plastic pipes over metal pipes are their greater resistance to aggressive media and incrustations, better Corrosion resistance, improved insulating effect, hygienic suitability, lighter weight, simpler connecting technique and installation as well as more favourable environmental properties. The plastics used for the production of pipes, such as polyvinyl chloride, uncrosslinked and crosslinked polyethylene, polybutene and polypropylene, which may be reinforced by inner or outer layers of metal, in particular aluminium, differ in the polymer used and the resultant different mechanical properties and the connecting technique. Clamping, screwing, pressing, pinching and sliding-sleeve systems, adhesive systems and heated-tool socket-fusion welding systems are used for the connection of pipes and moulded parts made of plastic. Permanent contact with oxidizing and reducing media in pipelines made of plastic degrade the chemical and mechanical properties of the plastic used as the pipe material. The macromolecules of the pipe material have a certain length and a certain number of chain entanglements with one another. The chain length and type of entanglements primarily determine the range of properties of the pipe material. Between the crystalline constituents of the polymer materials used with preference as pipe materials there are noncrystalline , amorphous regions, which allow the crystalline components in the polymer to displace and bring about a certain elasticity and toughness of the pipe material. To prevent damage to the polymer material used for pipes, additives such as metal deactivators, chlorine acceptors, acid acceptors, radical interceptors, UV stabilizers, process stabilizers and long-term heat stabilizers may be incorporated in the amorphous regions of the said material. These additives must be bonded into the polymer matrix in such a way that they resist extraction but are capable of migration. The additives are able to move in the amorphous regions of the polymer material. This effect is desired to allow the required additive to migrate to the location in contact with the medium, at which it develops a protective effect against the aggressive media and protects the polymer chains from being damaged. One decisive disadvantage of pipes made of polymer material with additives is that a considerable proportion of the additives migrates via the amorphous regions from the inner layer via the middle layer into the outer layer of the pipes, in which the additives are not required. If the effectiveness of the additives is exhausted or transformed by their protective mechanism, molecular damage, known as chain degradation, begins in the inner layer of the pipes, which is in contact with the medium flowing through the pipes. The pipe material becomes brittle, hard and liable to break. The wall thickness of the pipe is reduced as a result of abrasion and chain degradation. Finally, the internal pressure of the pipe leads to rupturing of the pipe. These degrading effects on the pipe material are very dependent on the medium and the temperature. As the temperature of the medium increases, there is a disproportionate increase in the rate of damage. The invention is based on the object of developing pipes, fittings and shaped parts made of plastic for creating pipelines for liquid, pasty and gaseous media with a high mechanical, chemical and thermal resistance. This object is achieved according to the invention by multi-layer pipes, fittings and shaped parts made of plastic which are characterized in that the inner layer and the middle layer consist of a polymer material, in that additives against aggressive media, in particular oxidizing and reducing media, are incorporated into the amorphous regions of the semicrystalline polymer material of the inner layer in contact with the medium to be transported and/or the middle layer, and in that fillers and/or additives are incorporated into the amorphous regions of the polymer material of the middle layer as barrier materials to reduce migration of the additives from the inner layer into the outer layer of the pipe, fitting or shaped part. The barrier effect of the migration-reducing middle layer of the pipes, fittings and shaped parts causes the effective additive components to remain in the inner layer, which comes into contact with the medium flowing through a pipeline. The migration of the additives to the outside and into layers or regions of the pipes, fittings and shaped parts which do not come into contact with the medium flowing through a pipeline is prevented. The diffusion of gases and liquids from outside through the pipe wall into the medium flowing in a pipeline is likewise reduced. On account of the barrier effect of the middle layer, the chemical and thermal resistance of the inner layer is increased. The permanent and sustained concentration of the additives in the inner layer of the pipes, fittings and shaped parts in contact with the flowing medium has the effect of successfully counteracting the attack of catalytic metal ions and the oxidizing attack of oxygen, acids and alkaline sqlutions and also free chlorine and other halogens even at relatively high operating temperatures and of increasing the resistance to these media. The plastic pipe characterized by a layered structure is also distinguished by high flexural and tensile strength, easy handling and working, good hygienic properties and good sound insulation from flow noises produced when a liquid medium flows through the pipe. The invention is explained below with reference to schematic drawings, in which: Figure 1 shows a perspective representation of a pipe for creating pipelines and Figure 2 shows an enlarged cross-sectional representation of the pipe according to detail I of Figure 1. The plastic pipe according to Figures 1 and 2 for creating pipelines for liquid, pasty and gaseous media, which is used with preference as a water pipe and which can be produced by extruding, injection-moulding or blow-moulding, has a pipe body 1 of a layered structure, with an inner layer 2 and an outer layer 3 of a base material and a middle layer 4 of a composite material, which consists of a base material and at least one additional material. The base material of the inner layer 2 and of the outer layer 3 of the plastic pipe consists of a polypropylene random copolymer. The composite material of the middle layer 4 of the plastic pipe is made up of a polypropylene random copolymer 5 with a weight content of 50 to 90, preferably 60 to 80, per cent by weight of glass fibres 6, glass beads 7 or glass powder 8 or mixtures of these materials with a weight content of 10 to 50, preferably 20 to 40, per cent by weight, and a coupling additive for the bonding together of the polypropylene random copolymer matrix 5 with the glass fibres 6 and/or the glass beads 7 and/or the glass powder 8. The polypropylene random copolymer of ^the composite material of the middle layer 4 has an ethene content of 2 to 6 per cent by weight and an MFR value (Melt Flow Rate value) of 0.3 to 10 grams/10 minutes at 190°C and a loading of 5 kilograms. The coupling additive for the bonding of the polyprcJpylene random copolymer matrix and the glass fibres, glass beads or glass powder or mixtures of these materials of the middle layer 4 of the pipe body 1 comprises a silane compound. The ethene is added to the composite material in order to reduce the embrittlement of the latter brought about by the fibre material and to give the material adequate elasticity- Processing aids such as lubricants and additives such as light stabilizers and heat stabilizers are admixed with the composite material of the middle layer 4 and/or the base material of the inner layer 2 of the plastic pipe. To prepare the starting composite material of the middle layer 4 of the plastic pipe, a plasticized or viscous polypropylene random copolymer with finely chopped glass fibres with a starting length of 0.1-6 millimetres or continuous fibres which are comminuted in the mixing operation, and/or with glass beads and/or with glass powder and also, if appropriate, stabilizers and additives is processed in a compounding unit into a homogeneous composite material, the glass fibres having a tex of between 500 and 5,000. The plastic pipe may be produced on a machine which is equipped with three extruders for extruding the inner layer 2, the middle layer 4 and the outer layer 3. For welding the plastic pipe to fittings or shaped parts, the end of the pipe to be connected and the inner wall of the bore of the fitting or shaped part is heated with a tool until the plastic flows, the tool comprising an electrically heated heating bushing for heating the end of the pipe and an electrically heated heating mandrel for heating the wall of the bore of the fitting or shaped part. After that, the pipe and fitting are separated from the tool, and the end of the pipe is pushed into the bore of the fitting, so that the two parts are welded to each other. The novel multi-layer plastic pipe can be used for creating pipelines for liquids, in particular drinking water lines and gas lines, and can be used in the chemical indus-try, in apparatus construction and the food industry. Patent claims 1. Extruded, injection-moulded or blow-moulded pipe, fitting or shaped part made of plastic for creating pipelines for liquid, pasty and gaseous media, with a pipe body made up of at least three layers, with an inner layer and an outer layer of a base material and a middle layer of a base material and at least one additional material, characterized in that the inner layer (2) and the middle layer (4) of the pipe, fitting or shaped part consist of a polymer material, in that additives against aggressive media, in particular oxidizing and reducing media, are incorporated into the amorphous regions of the semicrystalline polymer material of the inner layer (2) in contact with the medium to be transported and/or the middle layer (4) , and in that fillers and/or additives are incorporated into the amorphous regions of the polymer material of the middle layer (4) as barrier materials to reduce migration of the additives from the inner layer (2) into the outer layer (3) of the pipe, fitting or shaped part. 2. Plastic pipe according to Claim 1, characterized in that the inner layer (2), middle layer (4) and outer layer (3) of the same consist of the same polymer material as the base material. 3. Plastic pipe according to Claim 2, characterized by the use of a polypropylene random copolymer as the base material for the inner layer (2), the middle layer (4) and the outer layer (3) of the plastic pipe. 4. Plastic pipe according to one of Claims 1 to 3, characterized by the following constituents of the composite material of the middle layer (4) of the plastic pipe: a) polypropylene random copolymer with a weight content of 50 to 90, preferably 60 to 80, per cent by weight, which has an ethene content of 2 to 6 per cent by weight and an MFR value of 0.3 to 10 grams/10 minutes at a test temperature of 190°C and 5 kilograms loading weight; b) glass fibres, glass beads or glass powder or mixtures of these materials with a weight content of 10 to 50, preferably 20 to 40, percent by weight; c) a coupling additive for the bonding of the polypropylene random copolymer matrix with the glass fibres and/or the glass beads and/or the glass powder. 5. Plastic pipe according to one of Claims 1 to 4, characterized in that processing aids such as lubricants are admixed with the composite material of the middle layer (4) and/or the base material of the inner layer (2) . 6. Plastic pipe according to one of Claims 1 to 5, characterized in that the base material of the outer layer (3) contains lubricants. 7. Plastic pipe according to one of the Claims 1 to 6, characterized in that the composite material of the middle layer (4) and/or the base material of the inner layer (2) contain or contains additives such as light stabilizers and heat stabilizers. 8. Plastic pipe according to one of Claims 1 to 7, characterized in that additives such as light stabilizers and heat stabilizers are incorporated into the base material of the outer layer (3). 9. Plastic pipe according to one of. Claims 1 to 8, characterized in that the coupling additive of the composite material of the middle layer (4) of the plastic pipe consists of a silane compound. 10. Method of preparing the starting composite material of . the middle' layer of the plastic pipe according to Claims 1 to 9, characterized in that a plasticized polypropylene random copolymer with finely chopped glass fibres with a starting length of 0.3 to 6 millimetres or with continuous glass fibres which are comminuted in the mixing operation, and/or with glass beads and/or with glass powder, stabilizers and additives is processed in a compounding unit into a homogeneous composite material, the glass fibres having a tex of between 500 and 5,000, 11. Extruded injection-moulded or blow-moulded pipe substantially as hereinbefore described. 12. Method of preparing the starting composite material of the middle layer of the plastic pipe substantially as hereinbefore described.

Full Text

Description
Title: Extruded, injection-moulded or blow-moulded pipe, fitting or shaped part made of plastic for creating pipelines for liquid, pasty and gaseous media
The invention relates to an extruded, injection-moulded or blow-moulded pipe, fitting or shaped part made of plastic for creating pipelines for liquid, pasty and gaseous media, with a pipe body made up of at least three layers, with an inner layer and an outer layer of a base material and a middle layer of a base material and at least one additional material (EP 0 470 605 Al).
The application areas for pipes made of metal, in particular copper, galvanized steel, high-grade steel and to a lesser extent lead, are restricted by certain media parameters such as the pH, flow rate and operating temperature. The corrosion behaviour of metal pipes and the release of heavy metals in the case of lead and copper pipes further restrict the possible applications of metal pipes for drinking water lines and lines required in the food industry. Added to this is the fact that in many cases the extraction of metals, the mining and transporting of ores and the smelting of ores as well as the production of metal pipes is no longer economical on account of the required expenditure of energy and is no longer justifiable with regard to environmental damage.
For the reasons mentioned above, plastic pipes are gaining increasingly in significance for the creation of pipelines for various application areas, such as the supply of drinking water, heating engineering, the food industry, apparatus construction and the chemical industry.
The advantages of plastic pipes over metal pipes are their greater resistance to aggressive media and incrustations, better Corrosion resistance,

improved insulating effect, hygienic suitability, lighter weight, simpler connecting technique and installation as well as more favourable environmental properties.
The plastics used for the production of pipes, such as polyvinyl chloride, uncrosslinked and crosslinked polyethylene, polybutene and polypropylene, which may be reinforced by inner or outer layers of metal, in particular aluminium, differ in the polymer used and the resultant different mechanical properties and the connecting technique. Clamping, screwing, pressing, pinching and sliding-sleeve systems, adhesive systems and heated-tool socket-fusion welding systems are used for the connection of pipes and moulded parts made of plastic.
Permanent contact with oxidizing and reducing media in pipelines made of plastic degrade the chemical and mechanical properties of the plastic used as the pipe material. The macromolecules of the pipe material have a certain length and a certain number of chain entanglements with one another. The chain length and type of entanglements primarily determine the range of properties of the pipe material. Between the crystalline constituents of the polymer materials used with preference as pipe materials there are noncrystalline , amorphous regions, which allow the crystalline components in the polymer to displace and bring about a certain elasticity and toughness of the pipe material.
To prevent damage to the polymer material used for pipes, additives such as metal deactivators, chlorine acceptors, acid acceptors, radical interceptors, UV stabilizers, process stabilizers and long-term heat stabilizers may be incorporated in the amorphous regions of the said material. These additives must be bonded into the polymer matrix in such a way that they resist extraction but are capable of migration.

The additives are able to move in the amorphous regions of the polymer material. This effect is desired to allow the required additive to migrate to the location in contact with the medium, at which it develops a protective effect against the aggressive media and protects the polymer chains from being damaged.
One decisive disadvantage of pipes made of polymer material with additives is that a considerable proportion of the additives migrates via the amorphous regions from the inner layer via the middle layer into the outer layer of the pipes, in which the additives are not required. If the effectiveness of the additives is exhausted or transformed by their protective mechanism, molecular damage, known as chain degradation, begins in the inner layer of the pipes, which is in contact with the medium flowing through the pipes. The pipe material becomes brittle, hard and liable to break. The wall thickness of the pipe is reduced as a result of abrasion and chain degradation. Finally, the internal pressure of the pipe leads to rupturing of the pipe. These degrading effects on the pipe material are very dependent on the medium and the temperature. As the temperature of the medium increases, there is a disproportionate increase in the rate of damage.
The invention is based on the object of developing pipes, fittings and shaped parts made of plastic for creating pipelines for liquid, pasty and gaseous media with a high mechanical, chemical and thermal resistance.
This object is achieved according to the invention by multi-layer pipes, fittings and shaped parts made of plastic which are characterized in that the inner layer and the middle layer consist of a polymer material, in that additives against aggressive media, in particular oxidizing and reducing media, are incorporated into the amorphous regions of the semicrystalline polymer material of the inner layer in

contact with the medium to be transported and/or the middle layer, and in that fillers and/or additives are incorporated into the amorphous regions of the polymer material of the middle layer as barrier materials to reduce migration of the additives from the inner layer into the outer layer of the pipe, fitting or shaped part.
The barrier effect of the migration-reducing middle layer of the pipes, fittings and shaped parts causes the effective additive components to remain in the inner layer, which comes into contact with the medium flowing through a pipeline. The migration of the additives to the outside and into layers or regions of the pipes, fittings and shaped parts which do not come into contact with the medium flowing through a pipeline is prevented. The diffusion of gases and liquids from outside through the pipe wall into the medium flowing in a pipeline is likewise reduced. On account of the barrier effect of the middle layer, the chemical and thermal resistance of the inner layer is increased. The permanent and sustained concentration of the additives in the inner layer of the pipes, fittings and shaped parts in contact with the flowing medium has the effect of successfully counteracting the attack of catalytic metal ions and the oxidizing attack of oxygen, acids and alkaline sqlutions and also free chlorine and other halogens even at relatively high operating temperatures and of increasing the resistance to these media. The plastic pipe characterized by a layered structure is also distinguished by high flexural and tensile strength, easy handling and working, good hygienic properties and good sound insulation from flow noises produced when a liquid medium flows through the pipe.
The invention is explained below with reference to schematic drawings, in which:
Figure 1 shows a perspective representation of a pipe for creating pipelines and

Figure 2 shows an enlarged cross-sectional representation of the pipe according to detail I of Figure 1.
The plastic pipe according to Figures 1 and 2 for creating pipelines for liquid, pasty and gaseous media, which is used with preference as a water pipe and which can be produced by extruding, injection-moulding or blow-moulding, has a pipe body 1 of a layered structure, with an inner layer 2 and an outer layer 3 of a base material and a middle layer 4 of a composite material, which consists of a base material and at least one additional material.
The base material of the inner layer 2 and of the outer layer 3 of the plastic pipe consists of a polypropylene random copolymer.
The composite material of the middle layer 4 of the plastic pipe is made up of a polypropylene random copolymer 5 with a weight content of 50 to 90, preferably 60 to 80, per cent by weight of glass fibres 6, glass beads 7 or glass powder 8 or mixtures of these materials with a weight content of 10 to 50, preferably 20 to 40, per cent by weight, and a coupling additive for the bonding together of the polypropylene random copolymer matrix 5 with the glass fibres 6 and/or the glass beads 7 and/or the glass powder 8.
The polypropylene random copolymer of ^the
composite material of the middle layer 4 has an ethene
content of 2 to 6 per cent by weight and an MFR value
(Melt Flow Rate value) of 0.3 to 10 grams/10 minutes at
190°C and a loading of 5 kilograms.
The coupling additive for the bonding of the polyprcJpylene random copolymer matrix and the glass fibres, glass beads or glass powder or mixtures of these materials of the middle layer 4 of the pipe body 1 comprises a silane compound.
The ethene is added to the composite material in order to reduce the embrittlement of the latter brought about by the fibre material and to give the material adequate elasticity-

Processing aids such as lubricants and additives such as light stabilizers and heat stabilizers are admixed with the composite material of the middle layer 4 and/or the base material of the inner layer 2 of the plastic pipe.
To prepare the starting composite material of the middle layer 4 of the plastic pipe, a plasticized or viscous polypropylene random copolymer with finely chopped glass fibres with a starting length of 0.1-6 millimetres or continuous fibres which are comminuted in the mixing operation, and/or with glass beads and/or with glass powder and also, if appropriate, stabilizers and additives is processed in a compounding unit into a homogeneous composite material, the glass fibres having a tex of between 500 and 5,000.
The plastic pipe may be produced on a machine which is equipped with three extruders for extruding the inner layer 2, the middle layer 4 and the outer layer 3.
For welding the plastic pipe to fittings or shaped parts, the end of the pipe to be connected and the inner wall of the bore of the fitting or shaped part is heated with a tool until the plastic flows, the tool comprising an electrically heated heating bushing for heating the end of the pipe and an electrically heated heating mandrel for heating the wall of the bore of the fitting or shaped part. After that, the pipe and fitting are separated from the tool, and the end of the pipe is pushed into the bore of the fitting, so that the two parts are welded to each other.
The novel multi-layer plastic pipe can be used for creating pipelines for liquids, in particular drinking water lines and gas lines, and can be used in the chemical indus-try, in apparatus construction and the food industry.

Patent claims
1. Extruded, injection-moulded or blow-moulded pipe,
fitting or shaped part made of plastic for creating
pipelines for liquid, pasty and gaseous media, with a
pipe body made up of at least three layers, with an
inner layer and an outer layer of a base material and a
middle layer of a base material and at least one
additional material, characterized in that the inner
layer (2) and the middle layer (4) of the pipe, fitting
or shaped part consist of a polymer material, in that
additives against aggressive media, in particular
oxidizing and reducing media, are incorporated into the
amorphous regions of the semicrystalline polymer
material of the inner layer (2) in contact with the
medium to be transported and/or the middle layer (4) ,
and in that fillers and/or additives are incorporated
into the amorphous regions of the polymer material of
the middle layer (4) as barrier materials to reduce
migration of the additives from the inner layer (2)
into the outer layer (3) of the pipe, fitting or shaped
part.
2. Plastic pipe according to Claim 1,
characterized in that the inner layer (2), middle layer
(4) and outer layer (3) of the same consist of the same
polymer material as the base material.
3. Plastic pipe according to Claim 2, characterized by the use of a polypropylene random copolymer as the base material for the inner layer (2), the middle layer (4) and the outer layer (3) of the plastic pipe.
4. Plastic pipe according to one of Claims 1 to 3, characterized by the following constituents of the composite material of the middle layer (4) of the plastic pipe:
a) polypropylene random copolymer with a weight content of 50 to 90, preferably 60 to 80, per cent by weight, which has an ethene content of 2 to 6 per cent by

weight and an MFR value of 0.3 to 10 grams/10 minutes at a test temperature of 190°C and 5 kilograms loading weight;
b) glass fibres, glass beads or glass powder or mixtures of these materials with a weight content of 10 to 50, preferably 20 to 40, percent by weight;
c) a coupling additive for the bonding of the polypropylene random copolymer matrix with the glass fibres and/or the glass beads and/or the glass powder.

5. Plastic pipe according to one of Claims 1 to 4, characterized in that processing aids such as lubricants are admixed with the composite material of the middle layer (4) and/or the base material of the inner layer (2) .
6. Plastic pipe according to one of Claims 1 to 5, characterized in that the base material of the outer layer (3) contains lubricants.
7. Plastic pipe according to one of the Claims 1 to 6, characterized in that the composite material of the middle layer (4) and/or the base material of the inner layer (2) contain or contains additives such as light stabilizers and heat stabilizers.
8. Plastic pipe according to one of Claims 1 to 7, characterized in that additives such as light stabilizers and heat stabilizers are incorporated into the base material of the outer layer (3).
9. Plastic pipe according to one of. Claims 1 to 8, characterized in that the coupling additive of the composite material of the middle layer (4) of the plastic pipe consists of a silane compound.
10. Method of preparing the starting composite material of . the middle' layer of the plastic pipe according to Claims 1 to 9, characterized in that a plasticized polypropylene random copolymer with finely chopped glass fibres with a starting length of 0.3 to 6 millimetres or with continuous glass fibres which are comminuted in the mixing operation, and/or with glass beads and/or with glass powder, stabilizers and additives is processed in a compounding unit into a

homogeneous composite material, the glass fibres having a tex of between 500 and 5,000,

11. Extruded injection-moulded or blow-moulded pipe substantially as
hereinbefore described.
12. Method of preparing the starting composite material of the middle
layer of the plastic pipe substantially as hereinbefore described.

Documents:

318-mas-2001-abstract.pdf

318-mas-2001-claims filed.pdf

318-mas-2001-claims granted.pdf

318-mas-2001-correspondnece-others.pdf

318-mas-2001-correspondnece-po.pdf

318-mas-2001-description(complete)filed.pdf

318-mas-2001-description(complete)granted.pdf

318-mas-2001-drawings.pdf

318-mas-2001-form 1.pdf

318-mas-2001-form 26.pdf

318-mas-2001-form 3.pdf

318-mas-2001-form 5.pdf

318-mas-2001-other document.pdf

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Patent Number

210218

Indian Patent Application Number

318/MAS/2001

PG Journal Number

50/2007

Publication Date

14-Dec-2007

Grant Date

25-Sep-2007

Date of Filing

16-Apr-2001

Name of Patentee

M/S. GERHARD ROSENBERG

Applicant Address

AM RITTERLOH 1, D-57439 ATTENDORN - ENNEST,

Inventors:

#	Inventor's Name	Inventor's Address
1	GERHARD ROSENBERG	AM RITTERLOH 1, D-57439 ATTENDORN - ENNEST,

PCT International Classification Number

F16L 9/12

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	100 18 324.7	2000-04-13	Germany