Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
  • B29C49/42—Component parts, details or accessories; Auxiliary operations
  • B29C49/64—Heating or cooling preforms, parisons or blown articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B3/00—Packaging plastic material, semiliquids, liquids or mixed solids and liquids, in individual containers or receptacles, e.g. bags, sacks, boxes, cartons, cans, or jars
  • B65B3/02—Machines characterised by the incorporation of means for making the containers or receptacles
  • B65B3/022—Making containers by moulding of a thermoplastic material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
  • B29C49/42—Component parts, details or accessories; Auxiliary operations
  • B29C49/4273—Auxiliary operations after the blow-moulding operation not otherwise provided for
  • B29C49/42808—Filling the article
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
  • B29C49/42—Component parts, details or accessories; Auxiliary operations
  • B29C49/64—Heating or cooling preforms, parisons or blown articles
  • B29C49/6604—Thermal conditioning of the blown article
  • B29C49/6605—Heating the article, e.g. for hot fill
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/13—Hollow or container type article [e.g., tube, vase, etc.]

Definitions

• the present invention relates to a method of pressurizing the interior of a thin-walled container to impart a high mechanical strength.
• the invention also covers the pressurized container thus obtained with high mechanical strength.
• Thin-walled containers are known for example in patent applications WO-O3 / 033361, EP-1468930 and EP-1527999.
• the rigidity of such a thin-walled container poses another problem because these containers are conditioned at room temperature and when these containers are placed in a cold environment, there is a phenomenon of collapse which causes deformation of the container. Therefore, when the thin-walled containers are filled cold with flat liquids such as mineral water, oil, fruit juice, milk, it is necessary to use an aseptic working system, necessarily. Then, to meet the need for rigidity, it is planned to put these thin-walled containers under internal pressure by including the so-called method of nitrogen drop which is commonly used industrially. This method consists in introducing into the filled container of the liquid to be conditioned, a drop of liquid nitrogen, immediately before capping, in the headspace of the container.
• the distribution means of this drop of nitrogen must be integrated in the chain and, therefore, they must be adapted to operate in an aseptic environment, which is a strong constraint: cleaning, sterilization, maintenance.
• An additional station involves an additional source of failure to stop a chain on which the interventions are difficult and long because it is necessary to put all the conditions of aseptic packaging.
• the liquid nitrogen at a strongly negative temperature, falls into the liquid at room temperature so that the drop of drop regularly causes splashing on the edges of the container.
• the material used for the manufacture of thin-walled containers is often PET, polyethylene terephthalate, known for its transparency, its low weight and its great possibilities of conformation.
• PET also allows a good conservation of the contained liquids.
• the present invention provides a method of pressurizing the interior of a thin-walled container, filled cold and containing a flat liquid to improve the rigidity of said container before opening, a method that overcomes the problems mentioned above .
• the thin-walled container is of the type manufactured in known manner by blowing from a preform.
• This container has the necessary volume and searched.
• the thin-walled container obtained has a weight ratio of material / wall surface of the order of 150 g / m 2 to 250 g / m 2 and more particularly 150 g / m 2 at 200 g / m 2 .
• the method of pressurizing, according to the present invention, a thin-walled container for containing a flat liquid consists of the succession of the following steps:
• This last so-called heating step of the wall is intended to heat only the wall taken in its thickness. This heat supply causes the relaxation of the stresses which had been frozen by the rapid cooling after deformation during manufacture.
• the residual stresses are bi-oriented.
• the container therefore tends to return to its original shape, that is to say that of the preform. Because of this tendency to a volume reduction, the interior of the container is pressurized and as the liquid is incompressible, the head space is compressed to a balance between the pressure exerted by the wall and the internal pressure.
• Such heating can be achieved by means of a hot air projection on the periphery of the container for a short time. It is necessary to reach temperature point causing stress relaxation in the material, also known as the glass transition point.
• the supply of heat energy must be important for a very short time.
• the PET which is bad conductor of the heat, absorbs the calories brought by the hot air, which leads to a fast release of the stresses and avoids the transmission of the calories to the liquid or at least renders totally negligible the quantity of calories transmitted .
• the internal pressurization according to the method of the present invention also makes it possible to compensate for the pressure decrease, which is small but may exist, related to the loss of a part of the liquid due to the permeability of the walls, these walls being very thin.
• the pressurization of the inside of the container also makes it possible to compensate for the collapse due to a decrease in temperature between the conditioning temperature and the storage temperature, before opening.
• Thin-walled containers thus produced having wall thicknesses such as the weight ratio of material / surface is between 150g / m 2 and 250g / m 2 , more particularly between 150 g / m 2 and 200 g / m 2 , can withstand significant loads because of their greatly improved rigidity, including such containers can be palletized and the pallets can themselves be stacked.
• Heating which is indicated that a preferred embodiment is that of hot air may also use infrared heaters.
• the material concerned is PET because it is currently the most used but any suitable material for making a container, likely to have residual stresses, come from deformation, is concerned by the present invention.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Containers Having Bodies Formed In One Piece (AREA)
• Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
• Press Drives And Press Lines (AREA)
• Auxiliary Devices For And Details Of Packaging Control (AREA)
• Basic Packing Technique (AREA)
• Filling Of Jars Or Cans And Processes For Cleaning And Sealing Jars (AREA)
• Vacuum Packaging (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=39315191

Family Applications (1)

Country Status (10)

Cited By (1)

Families Citing this family (2)

Family Cites Families (44)

• 2007
  • 2007-10-10 FR FR0758188A patent/FR2922151B1/fr not_active Expired - Fee Related
• 2008
  • 2008-10-09 JP JP2010528459A patent/JP2011500457A/ja active Pending
  • 2008-10-09 AU AU2008315891A patent/AU2008315891A1/en not_active Abandoned
  • 2008-10-09 WO PCT/FR2008/051825 patent/WO2009053615A2/fr not_active Ceased
  • 2008-10-09 CN CN200880111758A patent/CN101842216A/zh active Pending
  • 2008-10-09 EP EP08842872A patent/EP2200809A2/de not_active Withdrawn
  • 2008-10-09 MX MX2010003780A patent/MX2010003780A/es not_active Application Discontinuation
  • 2008-10-09 CA CA2702282A patent/CA2702282A1/fr not_active Abandoned
  • 2008-10-09 US US12/681,955 patent/US20100209635A1/en not_active Abandoned
• 2010
  • 2010-04-08 ZA ZA2010/02461A patent/ZA201002461B/en unknown

Non-Patent Citations (1)

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