Rhone-Poulenc Industries

Sollac

Rhone-Poulenc S.a.

Rhone-Poulenc Chimie

Claude Bonnebat

Gilbert Roullet

Louis Macabrey

Thierry Soas

Jean-Pierre Quentin

Alain Morin

Fr&eacute;d&eacute;ric Jenny

Olivier Brun

Samy Branci

Gerard Halna Du Fretay

Yves Vaginay

A method and device for continuously coating at least a metal strip ( ) with a crosslinkable polymer fluid film which is free of non-reactive solvent or diluent, and which has a softening temperature higher than 50&deg; C. The method includes the steps of: continuously unwinding the metal strip ( ) on at least a back-up roll ( ); forming, by forced flow on an applicator roll ( ) having a deformable surface, a layer of the crosslinkable polymer; and forming on the applicator roll ( ) the crosslinkable polymer film and transferring the film from the applicator roll onto the metal strip. The device implements this method.

Method and device for continuously coating at least a metal strip with a crosslinkable polymer fluid film

A method for the continuous coating of at least one metal strip with a fluid, crosslinkable polymer film free from solvent or diluent and having a thickness less than that of the metal strip. The process firs continuously moves the metal strip on at least one support roller, pre-heats the strip, forms by forced flow, on a pinch roller on a lap of the crosslinkable polymer, heats and drives in rotation the pinch roller in the same direction as the support roller, and forms the crosslinkable film by compressing, between the pinch roller and the metal strips, an applicator element with a deformable surface, heated and driven in rotation in the same direction as the support roller to transfer the film from the pinch roller onto the applicator element and from the applicator element onto a metal strip. A coating device for implementing this method is also disclosed.

Method and device for continuous coating of at least one metal strip with a fluid cross-linkable polymer film

The invention concerns a method for continuously coating at least a metal strip with a crosslikable polymer fluid film free of non-active solvent or diluent and whereof the softening temperature is higher than 50&deg; C. The method consists in continuously unwinding the metal strip ( ) on at least a back-up roll ( ); forming, on a roll ( ) by forced flow, a layer of said crosslinkable polymer in melted state; forming, from said layer ( ), said crosslinkable polymer film ( ); and transferring entirely in thickness said film onto the metal strip ( ) and, between the zone forming the layer ( ) on the roll ( ) and the zone applying the film ( ) on the metal strip, in thermally conditioning the crosslinkable polymer to reduce its viscosity. The invention also concerns a coating device for implementing said method.

Method and device for measuring the thickness of an insulating coating

Polyvinyl alcohol films are provided which are gelled, non-tacky, bubble-free and resistant to water at ambient temperatures. The polyvinyl alcohol film is obtained by plasticizing (fluxing) and melting granules of pure polyvinyl alcohol containing from 25 to 35% by weight of water at a temperature at least 100.degree. C. above the equilibrium melting point of the granules and less than or equal to 220.degree. C., and extruding the melted granules through a die at a temperature at least 5.degree. C. above the equilibrium melting point of the granules and less than or equal to 98.degree. C., optionally followed by monoaxial stretching or biaxial stretching of the unstretched film obtained. The stretched or unstretched film may be heat-treated to improve its properties. The polyvinyl alcohol film can be used to prepare with thermoplastic films composite films or sheets having a high gas impermeability. The invention also provides composite, biaxially oriented, impermeable barrier layer coated, thermoplastic hollow shaped articles useful as packaging materials, e.g., as packages and bottles for flavored foods and carbonated beverages. The hollow shaped articles are produced by externally barrier covering a thermoplastic tubular blank, parison or preform with a relatively thick barrier layer consisting essentially of water-resistant and highly crystalline polyvinyl alcohol, said barrier layer having been prepared by shaping a melt of homogeneously shear fluxed and molten flakes or pure polyvinyl alcohol having a water content of 25 to 35% by weight thereof, with said shear fluxing and melting of said polyvinyl alcohol flakes being at a temperature above the equilibrium melting point of the polyvinyl alcohol/water admixture essentially constituting said flakes, and said shaping being at a temperature of at least said equilibrium melting point but less than that at which the vapor pressure of the component water would effect the surface expansion and bubbling of the desired barrier layer, and thence biaxially orienting and blow molding into final configuration said barrier covered blank, parison or preform.

Water-resistant polyvinyl alcohol film and its application to the

Smooth, thin, dimensionally stable, essentially circular and planar injection-molded disc members, well adapted as substrates for magnetic recording discs, e.g., by providing same with an effective recording amount of a magnetic coating material on at least one of the face surfaces thereof, comprise a radially molecularly oriented thermotropic polymer, desirably having a flow temperature ranging from 200.degree. C. to 350.degree. C. and an inherent viscosity of at least 1 dl g.sup.-1.

Highly oriented thermotropic magnetic recording medium

Rigid, dimensionally stable, essentially circular and planar, axially injection-molded disc members, well adapted as support substrates for radiation sensitive layers for optical discs, e.g., laser discs, comprise radially molecularly oriented thermotropic polymers and such disc members have a radiation-sensitive microrelief pattern on at least one of the face surfaces thereof.

Highly oriented thermotropic optical disc member

Polyvinyl alcohol films are provided which are gelled, non-tacky, bubble-free and resistant to water at ambient temperatures. The polyvinyl alcohol film is obtained by plasticizing (fluxing) and melting granules of pure polyvinyl alcohol containing from 25 to 35% by weight of water at a temperature at least 100.degree. C. above the equilibrium melting point of the granules and less than or equal to 220.degree. C., and extruding the melted granules through a die at a temperature at least 5.degree. C. above the equilibrium melting point of the granules and less than or equal to 98.degree. C., optionally followed by monoaxial stretching or biaxial stretching of the unstretched film obtained. The stretched or unstretched film may be heat-treated to improve its properties. The polyvinyl alcohol film can be used to prepare with thermoplastic films composite films or sheets having a high gas impermeability. The invention also provides composite, biaxially oriented, impermeable barrier layer coated, thermoplastic hollow shaped articles useful as packaging materials, e.g., as packages and bottles for flavored foods and carbonated beverages. The hollow shaped articles are produced by externally barrier covering a thermoplastic tubular blank, parison or perform with a relatively thick barrier layer consisting essentially of water-resistant and highly crystalline polyvinyl alcohol, said barrier layer having been prepared by shaping a melt of homogeneously shear fluxed and molten flakes of pure polyvinyl alcohol having a water content of 25 to 35% by weight thereof, with said shear fluxing and melting of said polyvinyl alcohol flakes being at a temperature above the equilibrium melting point of the polyvinyl alcohol/water admixture essentially constituting said flakes, and said shaping being at a temperature of at least said equilibrium melting point but less than that at which the vapor pressure of the component water would effect the surface expansion and bubbling of the desired barrier layer, and then biaxially orienting and blow molding into final configuration said barrier covered blank, parison or preform.

Method of extruding and blow molding of gas-impermeable composite

Polyvinyl alcohol films are provided which are gelled, non-tacky, bubble-free and resistant to water at ambient temperatures. The polyvinyl alcohol film is obtained by plasticizing (fluxing) and melting granules of pure polyvinyl alcohol containing from 25 to 35% by weight of water at a temperature at least 100.degree. C. above the equilibrium melting point of the granules and less than or equal to 220.degree. C., and extruding the melted granules through a die at a temperature at least 5.degree. C. above the equilibrium melting point of the granules and less than or equal to 98.degree. C., optionally followed by monoaxial stretching or biaxial stretching of the unstretched film obtained. The stretched or unstretched film may be heat-treated to improve its properties. The polyvinyl alcohol film can be used to prepare with thermoplastic films composite films or sheets having a high gas impermeability. The invention also provides composite, biaxially oriented, impermeable barrier layer coated, thermoplastic hollow shaped articles useful as packaging material, e.g., as packages and bottles for flavored foods and carbonated beverages. The hollow shaped articles are produced by externally barrier covering a thermoplastic tubular blank, parison or preform with a relativley thick barrier layer consisting essentially of water-resistant and highly crystalline polyvinyl alcohol, said barrier layer having been prepared by shaping a melt of homogeneously shear fluxed and molten flakes of pure polyvinyl alcohol having a water content of 25 to 35% by weight thereof, with said shear fluxing and melting of said polyvinyl alcohol flakes being at a temperature above the equilibrium melting point of the polyvinyl alcohol/water admixture essentially constituting said flakes, and said shaping being at a temperature of at least said equilibrium melting point but less then that at which the vapor pressure of the component water would effect the surface expansion and bubbling of the desired barrier layer, and then biaxially orienting and blow molding into final configuration said barrier covered blank, parison or preform.

An elongate, rigid, tubular, biaxially oriented thermoplastic, hollow thin-walled shaped article is molded by (i) introducing into an elongate mold cavity, the internal configuration and dimensions thereof corresponding to the exterior surface area of the desired shaped article, and aligning along the longitudinal axis thereof, a hollow tubular thermoplastic preform heated to the biaxial orientation temperature of said thermoplastic; (ii) expanding under internal pressure said heated preform to simultaneously, both longitudinally and transversely, uniformly stretch same, at least to the natural biaxial drawing ratio thereof, but to a value in the transverse direction of less than 100% of that ultimately desired; (iii) next further expanding said heated preform, under increased internal pressure, completely against the internal walls of the mold cavity to thus completely shape said ultimately desired shaped article; and (iv) then cooling said desired shaped article and releasing all pressure therefrom.

Molding of elongate, hollow, biaxially oriented thermoplastic shaped

A process for preparing biaxially oriented hollow shaped articles, in particular bottles of thermoplastic material, by biaxial draw- and blow-molding comprises blow-molding a preform and subsequently maintaining the thermoplastic material in close contact with the hot walls of the mold at a temperature which is in the range from about the minimum effective temperature for biaxial orientation of the thermoplastic material to about 40.degree. C. above this temperature for a period of time which is sufficient to partially reduce internal residual stresses in the hollow shaped articles. Following this partial thermo-stabilization, the hollow shaped article preferably is subjected to cooling, whereby the pressure within the article is at least partially maintained or the shaped article is cooled or allowed to shrink and subsequently subjected to a second blow-molding procedure.

Process for preparing biaxially oriented hollow shaped articles from

Novel polyester for the packaging of perishable comestibles, e.g., as bottles for still or carbonated mineral waters, is a poly(ethylene glycol)terephthalate (PET) having an intrinsic viscosity ranging from 0.65 to 1.05 dl/g and a density of more than 1.38, comprising 92.5 to 98.5% of ethylene terephthalate recurring units and 1.5 to 7.5 mol % of recurring units of at least one polybasic acid and/or polyhydric alcohol comonomeric crystallization retardant, the di- and/or triethylene glycol content thereof being less than about 3.5 mol % per mol of diacid radicals present in the polymer chain, said PET also having a residual acetaldehyde concentration of less than 1.25 ppm, with acetaldehyde being reformed therefrom at a rate of less than 5 ppm/hour, at 220.degree. C., and said PET being devoid of visible crystallization in an at least 4 mm thick test plate shaped in a mold cavity from a melt thereof.

Novel polyester for the packaging of comestibles

Hollow shaped articles are extruded, advantageously continuously extruded, from molten thermoplastics by controlled cooling of the molten charge prior to entry into an extrusion die.

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Pontault Combault, France

Claude Bonnebat