(19) 9)
`
`Europfiisches Patentamt
`
`European Patent Office
`
`Office européen des brevets
`
`(11)
`
`EP1 479 716 A1
`
`(12)
`
`EUROPEAN PATENT APPLICATION
`
`(43) Date of publication:
`24.11.2004 Bulletin 2004/48
`
`(51) Int C|.7: C08J 9/00, C08J 9/14
`
`(21) Application number: 03101486.3
`
`(22) Date of filing: 22.05.2003
`
`(84) Designated Contracting States:
`AT BE BG CH CY CZ DE DK EE ES FI FR GB GR
`HU IE IT LI LU MC NL PT RO SE SI SK TR
`
`Designated Extension States:
`AL LT LV MK
`
`(71) Applicant: NMC S.A.
`B-4731 Raeren (BE)
`
`(72) Inventor: Job, Den
`4031 Angleur (BE)
`
`is
`
`(74) Representative: Kihn, Pierre Emile Joseph et al
`Office Ernest T. Freylinger S.A.
`234, route d’Ar|on
`B.P. 48
`8001 Strassen (LU)
`
`
`
`(54)
`
`High temperature resistant, flexible, low density polypropylene toams
`
`ymer is between 9
`
`0/10 and 30/70 and
`
`0
`
`a permeability modifier.
`
`High temperature resistant, high flexibility and
`(57)
`low density foam comprising from:
`
`-
`
`-
`
`about 5 to about 95 weight percent of a High Melt
`strength polypropylene,
`
`about 95 to about 5 weight percent of a polypropyl-
`ene modified with ethylene/C3—C1 2 alpha—olefin co-
`polymers, where the weight ratio between polypro-
`pylene and the ethylene/C3-C1 2 alpha—olefin copol—
`
`EP1479716A1
`
`PAGE 1 OF 9
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`Printed by Jouve, 75001 PARIS (FR)
`
`BOREALIS EXHIBIT 1006
`
`BOREALIS EXHIBIT 1006
`
`PAGE 1 OF 9
`
`

`
`Description
`
`EP 1 479 716 A1
`
`[0001] The present invention relates to polypropylene foams with highertemperature resistance, betterflexibility and
`with an improved dimensional stability.
`[0002]
`Polypropylene is the most versatile commodity plastic, remaining thefastest growing major polymer. It is used
`in various industries for its wide range of mechanical, thermal and optical properties. Due to the numerous processes
`and catalysts available to synthesize polypropylene and its copolymers, this ‘polymer family‘ offers some decisive
`advantages over other resins, among which one can highlight:
`
`-
`-
`-
`-
`-
`-
`-
`-
`
`commodity thermoplastic;
`ease of processability;
`high temperature resistance;
`high rigidity;
`low density (900 to 917 kg/m3, depending on comonomer content);
`extended range of flow properties;
`hydrolytical stability;
`recyclability.
`
`Foams can benefit from the properties of the polypropylenes. Higher temperature resistance, higher rigidity
`[0003]
`for a given density of the foam, can be obtained as compared to a conventional foamable low melting point polyolefins
`such as |ow—density polyethylene.
`[0004] A typical direct gassing foaming process proceeds as follows: polymers and optional additives are fed in the
`entrance zone ofthe cylinder of an extruder, having single or double screws (co— or counter—rotatives). The components
`are molten in the cylinder, then gas is injected at a certain point of the cylinder, the whole mixture is homogeneously
`cooled down, and finally flows through a die in which foaming begins clue to pressure drop, causing insolubility of the
`gas in the melt and bubble formation. During the free expansion of the polypropylene foam to the outside atmosphere,
`cells are growing and the cell walls are highly stretched. They remain in a partially molten state for a while, and the
`viscosity build up at that moment is crucial forthe cell stability and the integrity of the finished foam
`[0005] The linear structure of most of the polypropylene types is leading to poor cell integrity, open cells structure
`and a lack offoamability. This is partly due to the non—branched structure causing the molecular chains to easily slipping
`over each other, without any other constraint than chain—to—chain friction. Moreover, the gap between melting point and
`crystallization point is wide (crystallization temperature often leads at i 100°C for non—nucleated PP, while melting
`point can be from 140°C to 170°C). As during thefoaming, the inner center of thefoam remains hotterthan the exterior
`because ofthe inherent thermal insulating properties of cellular materials, cells atthe middle of the foams are opening
`easily. Mechanical properties of the resulting foams are poor.
`[0006]
`In the particular case of direct gassing foaming processes, if a foam density as low as 15 to 20 kg/m3 is
`desired, having a majority of closed cells, it is necessary to use a special kind of polypropylene, the so—called << High
`Melt—strength >> (referred to hereafter as << HMS PP >>) grades. These grades possess long—chain branched structure,
`which leads to entanglements of the molecular chains. In the molten state, if such HMS PP ar e stretched, the disen-
`tanglement step of the molecular chains leads to an increase of the shear & elongational viscosity, which is favorable
`to maintain cell wall integrity during expansion in the still molten state. Furthermore, branches are believed to induce
`crystal nucleation, so that the temperature gap between melting point and crystallization point is reduced: the crystal-
`lization temperature rises to 120—125°C while the melting point is unaffected. This is definitely promoting closed—cells
`structure of the foam.
`
`[0007] BASELL Pro—Fax PF 814, BOREALIS DAPLOY 130D have both the aforementioned long—chain branching
`structure, introduced by a post—reactor step, either by irradiation (BASELL) or by reactive extrusion (BOREALIS), and
`are up to now the main materials successfully used to produce very low density foams.
`[0008] The foams obtained by using HMS PP can have a very low density, provided a maximum of HMS PP is used.
`The counterpart polymer may be another conventional linear polypropylene homopolymer or copolymer, having a melt-
`ing point range from 140°C to 170°C, as measured by Differential Scanning Calorimetry (DSC). Foams made from
`polypropylene are reported in the prior art to be more rigid than LDPE foams for example, influenced by the higher E-
`modulus of conventional homopolymer or copolymer (random or bloc) polypropylenes compared to LDPE.
`[0009]
`International patent application WO 01/94092 [TH ERMAFLEX INTERNATIONAL HOLDING] discloses a proc-
`ess for producing a polyolefin foam having higher temperature resistance and comprising a polypropylene and/or pol-
`yethylene. The process comprises first mixing and melting one or more polyolefins having a melting range, measured
`by means of differential scanning calorimetry at a heating rate of 10°C/min, within the range of 95°C to 170°C, with
`optionally other polyolefins and/or additives, so as to form a homogeneous mixture having a melt temperature within
`the range of 120 to 160°C, melting said homogeneous mixture in an extruder, mixing said molten mixture with a physical
`
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`

`
`EP1 479 716 A1
`
`foaming agent and cooling it to produce a foam at atmosphere. The polyolefins having a melting range from 95 to
`170°C are constituted from polypropylene having melting temperature range within 140 to 170°C, and PROFAX 814
`HMS—PP from BASELL is cited as representative of the polypropylene used. The other polyolefin can be a polyethylene
`having a melting range from 95 to 135°C, for example low density polyethylene, high density polyethylene, or EVA.
`[0010]
`Further in this patent application, it is pointed out that foams having a high polypropylene content have the
`best temperature resistance BUT are somewhat less flexible than the foams having a lower polypropylene content.
`The flexibility of foams containing from 40 to 95% by weight of polypropylene having a melting range within the range
`of 140 to 170°C are said to have in general aflexibility of 0.10 N/mm? at 20% impression, measured according to DIN
`53577, while the foams containing from 0 to 40% by weight of polypropylene having a melting range within the range
`of 140 to 170°C in general have a flexibility of 0.060 N/mm? at 20% impression, measured according to DIN 53577.
`[0011]
`Finally, WO 01/94092 teaches the advantage of compounding the polymers and additives priorto the extrusion
`of the foam, so that one single DSC melting peak is obtained.
`[0012] However, there are end uses that require both higher temperature resistance and improved flexibility.
`[0013] The present invention addresses the request for foams having improved flexibility while possessing a high
`thermal resistance, higher than existing flexible foams made, for example, from LDPE, or the aforementioned combi-
`nation of polypropylene and polyethylene disclosed in WO 01/94092.
`[0014] The foams of the present invention comprise from about 5 to about 95 weight percent of a High Melt Strength
`polypropylene. The remaining 95 to 5 weight percent will comprise from 95 to 5 weight percent of a polypropylene
`modified with ethylene/C3—C12 alpha—olefin copolymers, where the weight ration between polypropylene and the eth-
`ylene/C3—C12 alpha—olefin copolymer is between 90/10 and 30/70. These materials are commercially available with
`thetradenames Moplen orTPO HIFAX (Basell), FINAPRO (Fina) and the like. These products, having a flexural mod-
`ulus equal or inferior to 200 MPa and a melting point between 140°C and 170°C, may eventually be complemented
`by a polypropylene resin having a melting point between 140°C and 170°C, like a polypropylene homopolymer AND/
`OR a polypropylene bloc (heterophasic) copolymer AND/OR a polypropylene random copolymer.
`[0015]
`Surprisingly, when associating HMS PP with such flexible polypropylene copolymers, the mechanical prop-
`erties of the resulting foams are greatly improved. The resulting foam is much more flexible than PP foams, while the
`melting temperature is still much higherthan for LDPE foams and higherthan the prior art combination of polypropylenes
`with polyethylenes.
`[0016] An advantage of the foams according to the invention is that the dimensional stability problem arising during
`extrusion of such flexible polypropylene foams is solved.
`[0017] HIFAX resins which are manufactured under CATALLOY BASELL proprietary synthesis may be sued in the
`present invention. They are elastomeric thermoplastic olefins, bloc copolymers of polypropylene, with a peculiarly high
`rubber content. In the following table, key properties are listed in order to compare conventional polypropylene types
`with some ofthe HIFAX grades used in the frame ofthe present invention; these resins will be identified as « TPO PP » :
`
`MFI
`
`230°C/2.16kg
`(g/10min.)
`ISO 1133
`
`Flexural
`Modulus
`
`(MPa)
`ISO 178
`
`Tensile
`Modulus
`(MPa)
`ISO 527-2
`
`Melting point
`(°C)
`ISO 3146
`
`3
`
`12
`
`0.3
`
`0.3
`
`0.3
`
`14
`
`2.5
`
`0.6
`
`1700
`
`1550
`
`1500
`
`800
`
`80
`
`163°C
`
`165°C
`
`165°C
`
`1100
`
`165°C
`
`
`
`2 162°C
`
`Producer
`
`BASELL
`
`BASELL
`
`DSM
`
`BASELL
`
`PROFAX PF-
`814
`
`HMS PP
`
`MOPLEN
`HP500N
`
`STAMYLAN
`P 11 E10
`
`HOSTALEN
`PP H 1022
`
`HPP
`
`HPP
`
`Bloc copo PP
`
`DSM
`
`STAMYLAN
`
`Random
`
`P RA1E10
`HIFAX CA 60
`
`copo PP
`TPO PP
`
`A H
`
`IFAX 7320
`
`TPO PP
`
`HIFAX CA
`020
`
`TPO PP
`
`BASELL
`
`BASELL
`
`BASELL
`
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`

`
`[0018]
`
`For comparison, here is the same set of property for a low—density polyethylene:
`
`EP1 479 716 A1
`
`Producer
`
`Type
`
`MFI 230°C]
`2.16kg (gl
`10min.) ISO
`1133
`
`Density Kgl
`m3
`
`Tensile
`Modulus (MPa)
`ISO 527-2
`
`Melting point
`
`(‘’C) ISO 3146 DSM
`
`STAMYLAN LD
`2601TX17
`
`LDPE
`
`0.65
`
`BASELL
`
`LUPOLEN
`1800 H
`
`LDPE
`
`1.6
`
`926
`
`919
`
`320
`
`200
`
`[0019]
`One clearly sees that the cited HIFAX grades potentially combine an exceptional flexibility with a high melting
`point, more comparable to those of the conventional polypropylene homo and copolymers.
`[0020]
`It is however necessaryto combine the HIFAX TPO with HMS PP in orderto reach low density foams. HIFAX
`by themselves are not foaming well at all, a minimum of 5 % HMS PP (PROFAX PF—814 from BASELL for example)
`is therefore necessary to help foaming of the composition of the present invention.
`[0021] Optionally, one can add to the above composition ethylenic polymers having a melting point from 95°C to
`135°C, such as a high pressure copolymer of ethylene (for example: ethylene ethyl acrylate [EEA], ethylene acrylic
`acid (EAA), ethylene methacrylic acid [EMAA], ethylene vinyl acetate [EVA], ethylene butyl acrylate [EBA]) AND/OR
`a low density polyethylene AND/OR a medium density polyethylene AND/OR a high density polyethylene, provided
`the required combination of flexibility and temperature resistance of the foamed blend is achieved.
`[0022] Gas for foaming are chosen among following products: short chain alkanes from C2 to C8, C02, HFC (134,
`134a, 152a) and their blends. Preferred blowing agentfor making very low density are butane and propane and mixtures
`thereof, especially recommended is the use of isobutane.
`[0023]
`All kind of additives known to the skilled man in the art can be used to improve processability and properties
`of thefoams ofthe present invention: flame retardant, antistatics, processing aids, nucleating agents, pigments, infrared
`reflector/absorber, anti—UV agents, antioxidants, etc.
`[0024] The dimensional stability of polypropylene foams is governed by the relative permeation of the foaming gas
`compared to the outside airthrough the polymer membrane of each cell wall.
`It is also known that physical blowing
`agents having a molar volume somewhat bigger than atmospheric gases (nitrogen, oxygen and CO2), permeate at a
`different rate than air components through polypropylene. This is the case for HCFC 142b, which permeates at one
`fifth of the rate of air in a PP resin. For an approximately sterically similar molecule, isobutane, it is verified in practice
`to permeate also more slowly than air in polypropylene: foam is blowing further after the day of extrusion. This phe-
`nomenon induces a variation in the dimensions and density, which is more or less acceptable.
`[0025] Despite the use of permeability modifiers known in the art, like GMS or a saturated fatty acid derivative (stear—
`amide for example) commonly used for volume stabilization of LDPE foams, a collapse of the foam occurs after some
`meter on the cooling line. Despite that the next day the foam has blown back to a lower density, the foam has never-
`theless a bad aspect surface.
`[0026]
`Surprisingly, it has been discovered that by adding a permeability modifier like stearamide or glycerol mono-
`stearate to the composition of the present invention, and by applying a rapid cooling on the foam surface immediately
`after the die exit, the collapse during extrusion is unexpectedly reduced and the surface aspect is improved. Cooling
`is ideally made by air blowing ring having the external shape of the foam profile to be made in order to maintain an
`equal cooling efficiency overthe entire external surface ofthe foam. Care must be taken to avoid a cooling of the die,
`which would freezethe foam. An insulating Teflon plate with a small aperture can be used, for example, placed against
`the die, letting the foam expand after passing through the aperture in the Teflon plate.
`[0027]
`Preferably, a direct gassing extrusion process is used for making the foams of the present invention. The
`process comprises the following steps
`
`-
`
`-
`
`-
`-
`
`-
`
`feeding the polymers and optional additives into an extruder and heating the blend in the cylinder of the extruder
`so as to melt and blend the polymers and the optional additives;
`injecting a blowing agent which is liquid under injection pressure but gaseous at ambient conditions, mixing ofthe
`gas and molten polymers and the optional additives in the last part of the cylinder;
`cooling and further homogenizing through a heat exchanger section, followed by a static mixer element;
`extruding the cooled mixture through a die, the mixture is expanding by evaporation of the dissolved gas due to
`pressure drop and insolubility limit, so as to form a foam;
`cooling the foam immediately after the die;
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`EP 1 479 716 A1
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`-
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`further cooling the foam to the atmosphere conditions and while drawing the foam slightly.
`
`is the
`[0028] Another advantage brought by the use of these HIFAX with high rubber content and low E—modulus,
`improvement of impact at low temperature. Foams in some automotive use have to maintain their flexibility event at
`deep freeze temperature such as —40°C. Without the use of impact modifier, it is impossibleto avoid break of thefoam.
`The combination of high melt strength polypropylene and CATALLOY rubber modified polypropylene allows to pass
`this test, without affecting the upper side of temperature resistance of the foams.
`[0029] Applications for such new foams are numerous. Their combined high flexibility and high temperature resist-
`ance allows to outperform flexible LDPE foams where higher service temperature are requested, in thermal insulation
`of pressurized steam waterfor example. Automotive industry is very pleased to replace non—thermoplastics parts, like
`PUR, or PVC components; lightweight, recyclable, higher temperature resistance and flexible new PP foams of the
`present invention are adequate candidates. Furthermore, << All PP car >> is a wish in automotive industry, and the per-
`centage of PP in automotive plastic parts is more and more increasing. Any shape can be made with the new formu-
`lation: tube, rectangles, hollow shapes, sheets, irregular convex or concave shapes ...in any thickness, density and
`cell size according to the final use request.
`[0030] Care must be taken aboutthe long—term stability of polypropylene, especially if in contactwith metal, peculiarly
`copper. Antioxidant packages, including metal deactivator, are available and can help to satisfy the automotive stand-
`ards. Maximum temperature for long—term exposure must be determined carefully, in the most severe condition. Peak
`temperatures have also to be tested. It is however clear that the new polypropylene foams of the present invention
`can withstand a higher long—term service temperature than LDPE foams.
`[0031]
`Finally, the «flexibility » of the resulting new foams, measured for example by compression stress at 20%
`deformation according to DlN53577, is superiorto prior art foams like those described in W0 01/94092, that is, a lower
`value of the force is required to compress foam of 20% (remains 80% of initial height). Dimensional stability during
`extrusion is improved.
`
`Comparative example 1, not representing the present invention
`
`[0032] A foam is prepared by introducing in a twin screw co—rotative extruder a blend made from 40 weight parts of
`HMS polypropylene PROFAX PF—814(BASELL) and 60 weight parts of a random copolymer STAMYLAN P RA1 E10
`(DSM, flexural Modulus = 800 MPa), adding 5 weight parts of a PP based masterbatch containing 40% wt talcum, 1
`weight part of glycerol monostearate ATMER 129, 5 parts of a PE based 5% fluoroelastomer masterbatch and 6 parts
`of a 25% antioxidant PP based masterbatch. The mixture is extruded at 20 kg/h, using 1,86 kg isobutane per hour as
`blowing agent. The melt is cooled through a heat exchanger section, then passes a static mixer and finally is extruded
`through a rectangular shape die. Melt temperature before the die is 153.7°C. No air is blown on thefoam surface. The
`resulting foams expands to the atmosphere, has a fresh density of 30.5 kg/m3, with 870 cells/cm? It seems rather
`stable in dimensions in the cooling bath. Size of the rectangular foam is 26 x 17.5mm. Foam is moderatly flexible,
`compression at 20% deformation (DIN 53577) in the direction of extrusion is 0.063 N/mm2. Next day, density has fallen
`to 26 kg/m3.
`
`Comparative example 2, not representative of the invention
`
`[0033] A foam is prepared by introducing in a twin screw co—rotative extruder a blend made from 60 weight parts of
`HMS polypropylene PROFAX PF—814 (BASELL) and 40 weight parts of TPO PP HIFAX CA020 (BASELL), adding 0.5
`weight parts of a PP based masterbatch containing 60% wt talcum, 5 weight parts of an EVA based masterbatch
`containing 90wt% stearamide ARMID HT (AKZO NOBEL). The mixture is extruded at 15 kg/h, using 1,5 kg isobutane
`per hour as blowing agent. The melt is cooled through a heat exchanger section, then passes a static mixer and finally
`is extruded through a rectangular shape die. Melt temperature before the die is 147.4°C. No air is blown on the foam
`surface. The resulting foams expands to the atmosphere, the flexibility is very attractive but foam begins to collapse
`in the cooling some meters after the die. Density at the end of the cooling bath is 30.2 kg/m3, foam is 30mmx20mm.
`After 1 day, density is 36 kg/m3 and surface is wrinkled. After 1 month, density is 27 kg/m3 but surface aspect is bad.
`
`Example 3, representative of the invention
`
`[0034] The composition and extrusion parameter of example 3 are taken, except that an air ring is placed around
`the foam right after the die. A Teflon plate with adequate aperture avoids that air blows on the die itself, which would
`cause a freezing in the die. Foam now is almost not collapsing in the cooling bath. Fresh density after cooling bath is
`30.2 kg/m3. After 1 day, density is 31.2 kg/m3 and surface OK. After1 month, density has fallen to 27 kg/m3, but surface
`aspect is much better than in comparative example 3.
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`Example 4, representative of the invention
`
`EP1 479 716 A1
`
`To make a small protection insulative tubular foam, a complex blend is fed through the same extruder as in
`[0035]
`Example 1
`:
`
`-
`-
`-
`-
`
`60 parts of HMS PP PROFAX 814 (BASELL);
`40 parts of TPO PP HIFAX CA 60 A (BASELL);
`6 parts of a 25% antioxidant PP based masterbatch ;
`4 parts of a 80% halogenated flame retardant + antimony trioxide combination PP based masterbatch ;
`1.5 parts of an EVA based masterbatch containing 90% of a 60/30 stearamide/palmitamide blend;
`1 part of a PP based 40% talcum masterbatch;
`5 parts of a PE based 5% fluoroelastomer masterbatch.
`
`[0036] The mixture is extruded at 12 kg/h, using 1,56 kg isobutane per hour as blowing agent. The melt is cooled
`through a heat exchanger section, then passes a static mixer and finally is extruded through a round shape die having
`2.4 mm diameter, the tool having also a bolt of 1.2 mm. Melt temperature before the die is 150.1°C. Air ring with a T
`eflon plate having adequate aperture to letthe foam pass is placed just atthe die aroundthe tubularfoam. The resulting
`foams expands to the atmosphere, has a fresh density of 34 kg/m3, with 400 to 450 cells/cm2. There is no major sign
`of collapse in the cooling bath. Outer diameter is 15mm, internal diameter is 7mm. The resulting foam is very flexible.
`Single peak melting point DSC is 156.58°C. On the next day density is 31.5 kg/m3, the surface aspect is excellent.
`
`Claims
`
`1. High temperature resistant, high flexibility and low density foam comprising:
`
`0
`
`0
`
`0
`
`from about 5 to about 95 weight percent of a High Melt strength polypropylene,
`
`from about 95 to about 5 weight percent of a polypropylene modified with ethylene/C3—C12 alpha—olefin co-
`polymers, where the weight ratio between polypropylene and the ethylene/C3—C12 alpha—olefin copolymer is
`between 90/10 and 30/70 and
`
`a permeability modifier.
`
`2.
`
`3.
`
`4.
`
`5.
`
`6.
`
`Foam according to claim 1 wherein the modified polypropylene has a flexural modulus equal or inferiorto 200 MPa
`and a melting point between 140°C and 170°C.
`
`Foam according to claim 1 or 2 further comprising a polypropylene resin having a melting point between 140°C
`and 170°C.
`
`Foam according to claim 3 wherein the polypropylene resin having a melting point between 140°C and 170°C is
`chosen among the group consisting of polypropylene homopolymer, polypropylene bloc (heterophasic) copolymer,
`polypropylene random copolymer and mixtures thereof.
`
`Foam according to claim 1 to 3 further comprising at least one ethylenic polymer having a melting point from 95°C
`to 135°C.
`
`Foam according to claim 4, wherein at least one ethylenic polymers having a melting pointfrom 95°C to 135°C is
`chosen among the group consisting of ethylene ethyl acrylate [EEA], ethylene acrylic acid (EAA), ethylene meth-
`acrylic acid [EMAA], ethylene vinyl acetate [EVA], ethylene butyl acrylate [E BA]), low density polyethylene, medium
`density polyethylene, high density polyethylene and mixtures thereof.
`
`7. Method for producing a foam according to any of the preceding claims comprising the steps of:
`
`0
`
`0
`
`feeding the polymers and optional additives into an extruder and heating the blend in the cylinder of the extruder
`so as to melt and blend the polymers and the optional additives;
`injecting a blowing agent which is liquid under injection pressure but gaseous at ambient conditions, mixing
`of the gas and molten polymers and the optional additives in the last part of the cylinder;
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`EP1 479 716 A1
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`cooling and further homogenizing through a heat exchanger section, followed by a static mixer element;
`extruding the cooled mixture through a die, the mixture is expanding by evaporation of the dissolved gas due
`to pressure drop and insolubility limit, so as to form a foam;
`cooling the foam immediately after the die,
`further cooling the foam to the atmosphere conditions and while drawing the foam slightly.
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`EP1 479 716 A1
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`0 ) EuropeanPatent
`
`Ofiwe
`
`EUROPEAN SEARCH REPORT
`
`ApplicationNumber
`
`EP 03 10 1486
`
`DOCUMENTS CONSIDERED TO BE RELEVANT
`Citation ol document with indication, where appropriate,
`of relevant passages
`
`Category
`
`Relevant
`to claim
`
`CLASSlF|CAT|0N OF THE
`APPLICATION (lfil-Cl-7)
`
`X
`
`>
`
`A
`
`A
`
`C08J9/00
`C08J9/14
`
`7
`
`1-6
`
`1-7
`
`1-?
`
`TECHNICAL FIELDS
`se/mcneo
`(lnl.CI.7)
`
`CG8J
`
`N0 01 94092 A (BELL HUMPHREY REGINALD DE
`;BOUT HENDRIK NILLEM (NL); THERMAFLEX IN)
`13 December 2001 (2001-12-13)
`* page 1,
`line 4-9 *
`page 3,
`line 10 - page 4,
`page 3,
`line 1-21 *
`page 5,
`line 1-19 *
`page 7,
`line 34 - page 8,
`
`line 9 *
`
`line 17 *
`
`>(*X'>l-if
`
`ET AL)
`US 5 180 751 A (KATZ LEON
`19 January 1993 (1993-01-19)
`* the whole document *
`
`EP 0 291 764 B (FURUKAWA ELECTRIC CO LTD)
`23 November 1988 (1988-11-23)
`* the whole document *
`
`The present search report has been drawn up for all claims
`Place of search
`Dale of completion of ilne search
`
`Examiner
`
`MUNICH
`CATEGORY OF CITED DOCUM ENTS
`X : particularly relevant if taken alone
`Y 2 particularly relevant if combined wflh another
`document of the same category
`A 2 technological background
`O : non-written disclosure
`P: intermediate document
`
`
`
`Lartigue, M-L
`15 September 2003
`T : theory or principle underlying the invention
`E : earlier patent document, but published on, or
`after the filing date
`D : document cited in the application
`L : document cited for other reasons
`
`31 : member of the same patentfarnlly, corresponding
`document
`
`
`
`EPOFORM150308.82(PC4001)
`
`PAGE 8 OF 9
`
`8
`
`PAGE 8 OF 9
`
`

`
`EP1 479 716 A1
`
`ANNEX TO THE EUROPEAN SEARCH REPORT
`ONEUROPEANPATENTAPPUCKHONNO.
`
`EP0310]486
`
`This annex lists the patent family members relating to the patent documents cited in the above-mentioned European search repoit.
`The members are as contained in the European Patent Office EDP file on
`The European Patent Oltice is in no way liable for these particulars which are merely given for the purpose of information.
`15-09-2003
`
`cited in search report
`
`date
`
`member(s)
`
`date
`
`NO 0194092
`
`A
`
`13-12-2001
`
`
`
`NO
`AU
`EP
`
`13-12-2001
`0194092 A1
`17-12-2001
`5256100 A
`12-03-2003
`1289727 A1
`
`
`
`
`
`
`
`
`
`US 5180751
`A
`19-01-1993
`US
`AT
`CA
`DE
`DE
`EP
`ES
`JP
`JP
`JP
`JP
`KR
`NO
`US
`
`5116881 A
`122701 T
`2078123 A1
`69109860 D1
`69109860 T2
`0520028 A1
`2072606 T3
`2638532 B2
`7266413 A
`2521388 B2
`5506875 T
`9603278 B1
`9113933 A1
`5149579 A
`
`
`
`26-05-1992
`15-06-1995
`15-09-1991
`
`22-06-1995
`26-10-1995
`30-12-1992
`16-07-1995
`06-08-1997
`17-10-1995
`07-08-1996
`07-10-1993
`08-03-1996
`19-09-1991
`22-09-1992
`
`
`
`EP 0291764
`
`8
`
`23-11-1988
`
`JP
`JP
`JP
`DE
`EP
`KR
`US
`
`1804603 C
`5011745 B
`63288731 A
`3864742 D1
`0291764 A1
`9108593 B1
`4832770 A
`
`26-11-1993
`16-02-1993
`25-11-1988
`17-10-1991
`23-11-1988
`19-10-1991
`23-05-1989
`
`EPOFORMP0459 For more details about this annex : see Official Journal of the European Patent Office, No. 12/82
`
`PAGE 9 OF 9
`
`9
`
`PAGE 9 OF 9