Classifications

• • 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
  • B65B61/00—Auxiliary devices, not otherwise provided for, for operating on sheets, blanks, webs, binding material, containers or packages
  • B65B61/18—Auxiliary devices, not otherwise provided for, for operating on sheets, blanks, webs, binding material, containers or packages for making package-opening or unpacking elements
  • B65B61/188—Auxiliary devices, not otherwise provided for, for operating on sheets, blanks, webs, binding material, containers or packages for making package-opening or unpacking elements by applying or incorporating profile-strips, e.g. for reclosable bags
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B70/00—Making flexible containers, e.g. envelopes or bags
  • B31B70/74—Auxiliary operations
  • B31B70/81—Forming or attaching accessories, e.g. opening devices, closures or tear strings
  • B31B70/813—Applying closures
  • B31B70/8131—Making bags having interengaging closure elements
  • B31B70/8132—Applying the closure elements in the machine direction

Definitions

• the present invention relates to a method for producing a resealable pouch such as that used for storing tobacco.
• the invention relates in particular to a method for inserting a resealable fastener into a pouch during the forming process of a standard tobacco pouch from a continuous reel of material.
• a pouch for tobacco is conventionally formed from a thermoplastic material, capable of being welded to itself using a combination of heat and pressure.
• the continuous material, or web is folded on itself along the length of the web from one side towards the other side, the fold being approximately a third the way along the width of the web, thus forming a double thickness web with a fold at one side and an extension of single thickness material extending from the double thickness to the opposite side of the web.
• the distance from the folded edge to the extremity of the double thickness will be approximately the same as the distance from the double thickness part of the web to the other edge.
• the double thickness part of the folded web is then welded, at fixed intervals across the width of the web, forming a continuous length of folded material formed into individual pockets of equal size, by the welds.
• the welds formed are of a reasonable thickness.
• the continuous length of formed pockets are cut by a knife along the welds, forming individual pouches welded at each side, with an extended flap approximately equal in length to the depth of the pouch.
• the individual pouches are filled with the product, tobacco, through the mouth of the pouch.
• the extended flap of the pouch is folded below the mouth of the pouch, but over the pouch mouth, so as to form the flap around the pouch.
• a second fold of the flap is made around the base of the pouch to form a completely wrapped pouch. This method of wrapping does not prevent loss of moisture from the contents, or spillage of the contents, before and during use.
• Document WO 83 04011 A discloses a method of producing a resealable pouch comprising a reclosable fastener.
• the pouch is formed from a plastic film and the reclosable fastener is welded to the film during a first step of the process.
• the object of the present invention is to provide a method of producing a resealable pouch by inserting a resealable fastener into the pouches during the forming process so as to enable enhanced moisture retention of the product, or perceived moisture retention by the user, and to enable a reduction in spillage of the product before and during the use of the pouch.
• the present invention provides a method of producing resealable filled pouches comprising the steps of folding across part of its original width a length of thermoplastics sheet to produce a folded sheet having a fold portion running lengthways of the sheet having a folded edge which fold portion extends across part of the original width of the sheet and a non fold portion extending from the fold portion to the other edge of the sheet; in a direction at right angles to the folded edge and at regular intervals along the folded edge, welding the fold portion together to form individual pockets of equal size having welded wall edges along the length of the sheet; cutting the sheet, across the width of the sheet and along the line of the welds, to produce individual pouches each having a mouth, welded edges and an extended flap portion; filling each pouch, through its mouth, with desired contents and folding the extended flap over the mouth so as to form the flap around the pouch; characterised in that, at the time of forming the fold portion of the sheet, a resealable fastener is located on the sheet in a direction parallel to the edges
• the fastener is supplied in the form of two interengaging closure strips, supplied in the engaged position.
• Each strip is typically formed with a protrusion, designed to engage with the complimentary strip, and flanges extending from the sides of the protrusion.
• the base of each of the closure strips may be provided with one or more flanges. It is a requirement that the closure strips are introduced and fixed into position, whilst engaged, so as to ensure perfect alignment between the two complimentary strips to ensure resealability. Any misalignment between the two complimentary strips will act so as to prevent full re-closure of the fastener or render the resealing action unworkable by the user. It is also a requirement of the process to ensure the closure is in the unengaged position when the pouch reaches the filling position. Both these actions are achieved in the manner described below.
• the pouch is formed in the manner described for a standard pouch, the resealable fastener, in its engaged position, being introduced into the forming process as the thermoplastic sheet is folded.
• the fastener is guided into the folded sheet into the position at which it is to be secured, i.e., immediately below what will become the mouth of the pouch,and the flanges of the closure strips are then welded to the pouch material in the correct position.
• Welding the fastener into the pouch while engaged ensures alignment is maintained between the complimentary strips. Care should be taken to ensure that the flanges from opposing complementary closure strips do not become welded together.
• the material and closure strips may be chilled, by a cooling mechanism, so as to prevent stretching or puckering of the material, which may occur due to retained heat.
• the closure strips which up to this point in time are engaged together are disengaged, whilst maintaining the positioning of the complimentary strips relative to each other.
• the opposing closure strips are welded together using a high-energy method of welding, such as ultra-sonic welding, at fixed points along their lengths which points coincide with the positions at which the side welds, to form the pouches, will be made.
• These welds are generally of a similar width as the side welds and act to ensure proper location of the opposing closures by closing the closures at the point of the weld, and "crushing" the closure with the ultra-sonic weld, or similar high-energy weld.
• an ultra-sonic weld or similar high-energy weld, ensures the opposing closures are securely welded together, such that the weld will not break under normal use of the pouch, and also acts to produce a thin weld, which does not adversely affect the visual impact of the pouch. It is important to note that, at this point, the closure, welded into mouth of the pouch, is in the unengaged position, and that the closure has to remain generally unengaged for the remainder of the forming and filling process. Also note that the ultra-sonic weld is designed to extend slightly beyond the width of the fastener for reasons that will become apparent.
• welds are made from the weld at the closure to the fold in the web, in the same manner as for the standard side weld.
• the side weld preferably does not extend to the same distance as the original weld, as the closure weld would cause adverse interference with side weld. Therefore, the side weld preferably welds from the fold in the web to immediately below the closure flanges, and acts to interfere with the extension of the closure weld below the flanges. This interference is important to ensure an airtight weld is maintained from the web fold to above the fastener.
• the guide strip used preferably extends throughout the pouch forming process up to the point the side welds are made, thus aiding with positive location and tracking of the closure and material.
• the continuous web of formed pouches, with the resealable fastener secured into the mouths of the pouches, is cut down the centre of the weld to form individual pouches sealed at each side, the resealable fastener remaining generally open. Any partial closing of the fastener that may have occurred can be eliminated by a blast of compressed air aimed at the mouth of the pouch.
• the individual pouches are then filled, subsequent to all formation of the individual pouches, through the mouth of the pouch.
• the preferred application of the invention is in the production of resealable pouches of tobacco, it is possible to fill the pouches with different products, such as food products.
• the fastener After deposition of the product into the pouch, the fastener is closed by means of pressure exerted onto the fastener.
• the pouch is preferably folded in a similar manner to that used in conventional pouch production; the first fold occurring between the filled pouch and the bottom of the fastener.
• the fastener is positioned such that the fold occurs in the same place as it does in a conventional pouch and hence does not affect the capacity of the pouch.
• a second fold of the flap around the base of the pouch can be made as in the conventional pouch.
• thermoplastics sheet used may be a sheet of polyethylene.
• the sheet may also be a laminate of a thermosplastics material with one or more layers of similar or different thermoplastics material, a metalised or metal coated sheet material or a paper Web.
• thermoplastics sheet may be supplied from a continuous reel.
• thermoplastics sheet may be folded such that the distance from the folded edge to the mouth of the pouch is equal to the distance from the mouth of the pouch to the edge of the extended flap.

Priority Applications (1)

Applications Claiming Priority (4)

Publications (2)

Family

ID=8241176

Family Applications (1)

Country Status (19)

Cited By (2)

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Family Cites Families (7)

• 2000
  • 2000-01-06 AT AT00900072T patent/ATE225733T1/de not_active IP Right Cessation
  • 2000-01-06 DE DE60000572T patent/DE60000572T2/de not_active Expired - Fee Related
  • 2000-01-06 AU AU18838/00A patent/AU771156B2/en not_active Expired
  • 2000-01-06 HU HU0104893A patent/HU224878B1/hu unknown
  • 2000-01-06 EP EP00900072A patent/EP1144253B1/en not_active Expired - Lifetime
  • 2000-01-06 WO PCT/GB2000/000020 patent/WO2000040465A1/en active IP Right Grant
  • 2000-01-06 EE EEP200100357A patent/EE200100357A/xx unknown
  • 2000-01-06 DK DK00900072T patent/DK1144253T3/da active
  • 2000-01-06 CN CN00802594A patent/CN1336888A/zh active Pending
  • 2000-01-06 JP JP2000592188A patent/JP2002534293A/ja active Pending
  • 2000-01-06 CA CA002358541A patent/CA2358541C/en not_active Expired - Lifetime
  • 2000-01-06 ZA ZA200105581A patent/ZA200105581B/en unknown
  • 2000-01-06 NZ NZ512603A patent/NZ512603A/xx not_active IP Right Cessation
  • 2000-01-06 CZ CZ20012463A patent/CZ300194B6/cs not_active IP Right Cessation
  • 2000-01-06 EA EA200100751A patent/EA003007B1/ru not_active IP Right Cessation
  • 2000-01-06 ES ES00900072T patent/ES2180507T3/es not_active Expired - Lifetime
  • 2000-01-06 PT PT00900072T patent/PT1144253E/pt unknown
  • 2000-01-06 ID IDW00200101702A patent/ID30078A/id unknown
• 2002
  • 2002-07-03 HK HK02104981.1A patent/HK1043098A1/zh unknown

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