Expandable bag and method of manufacture

• US 4,510,734 A
• Filed: 09/16/1982
• Issued: 04/16/1985
• Est. Priority Date: 07/25/1980
• Status: Expired due to Term

• Current Assignee: CCL Technologies Incorporated
• Original Assignee: Enviro-Spray Systems Incorporated
• Inventors: Banks, Russell, Magid, David J.
• Primary Examiner(s): Culver, Horace M.
• Application Number:
  US06/419,073
• Time in Patent Office: 943 Days
• Field of Search: 53/470, 53/474, 53/433, 53/434, 53/453, 53/454, 53/449, 222/386.5
• US Class Current: 53/449
• CPC Class Codes: B65D 81/32 for packaging two or more different materials which must be maintained separate prior to use in admixture containers with removable or destructible partitions B65D25/08 ; closures combined with auxiliary containers B65D51/28; in aerosol containers B65D83/682; amalgam capsules A61C5/66; containers for pharmaceutical purposes A61J1/20, A61M5/19; medical syringes A61M3/005, resin cartridges for grouting anchoring-bolts in mines E21D20/026
• CPC Class Codes: B65D 83/14 for delivery of liquid or semi-liquid contents by internal gaseous pressure, i.e. aerosol containers comprising propellant for a product delivered by a propellant
• CPC Class Codes: B65D 83/625 the propellant being generated by a chemical or electrochemical reaction for pressure gas in portable fire extinguishers A62C13/02

Abstract

A fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing the bag to expand gradually from a collapsed condition to an ultimately fully expanded condition. The internal compartmentation in the bag also contains a solvent medium and a time release capsule of one of the components, thereby providing apparatus that can be mass produced and used for insertion into aerosol-type liquid product dispensing containers to provide relatively constant expulsion pressure during use.

Claims

1. The method of fabricating a fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing said bag to expand gradually from a collapsed condition to an ultimate fully expanded condition comprising the steps of:

(a) forming a group of pockets in a first plastic sheet, said pockets being aligned in a staggered series;

(b) fabricating a rupturable solvent containing means associated with said first sheet;

(c) introducing measured amounts of said first component into each pocket of said group;

(d) placing a second plastic sheet over said first group of pockets and releasably sealing it at least at its marginal areas to said first sheet;

(e) placing time release capsule containing said first component, and a measured amount of said second component on a portion of said first sheet spaced from all of said pockets; and

(f) permanently sealing a third plastic sheet to said first sheet at the marginal areas of both and to said second sheet to provide a bag-like enclosure containing within its interior all of said compartments, and said second compartment.

2. In the method of claim 1, each said sheet being laminated polyethylene/polypropylene, and having the releasably sealed surfaces being a polyethylene to polypropylene bond and the permanently sealed surfaces being a homogeneous bond of the same plastic.

3. In the method of claim 2, step (a) using vacuum forming and steps (d) and (f) employing heat sealing.

4. In the method of claim 3, the measured amounts of said first component totalling the stoichiometric amount required to completely react with the measured amount of said second component in step (e), and the amount of solvent medium in step (b) being sufficient to dissolve all of said first and second components.

5. The method according to claim 4 including forming successive interconnected bags in a continuous plastic sheet, winding said continuous sheet containing the formed bags into a supply roll for transport and subsequent use.

6. In the method of claim 4, said first component is citric acid, said second component sodium bicarbonate, and said solvent medium is water.

7. The method of fabricating a fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing said bag to expand gradually from a collapsed condition to an ultimate fully expanded condition comprising the steps of:

(a) forming a plurality of pockets in a first plastic sheet, said pockets being aligned in a staggered series;

(b) introducing measured amounts of said first component into each pocket of said group;

(c) placing a rupturable plastic enclosure on said first sheet containing a solvent medium and said second component;

(d) placing a second plastic sheet over said pockets and releasably sealing it at least at its marginal areas to said first sheet; and

(e) permanently sealing a third plastic sheet to said first sheet at the marginal areas of both and to said second sheet to provide a bag-like enclosure containing within its interior all of said compartments, said second sheet and said enclosure.

10. In the method of claim 7, step (d) including releasably sealing said second sheet to said first sheet in a plurality of relatively short angular guard seals adjacent said pockets and step (e) including permanently sealing said second and third sheets together in an elongated separation seal running generally longitudinally and centrally of said bag.

8. The method of fabricating an aerosol-type container for dispensing a liquid product on demand in which the internal pressurizing means in said container is a fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing said bag to expand gradually from a collapsed condition to an ultimate fully expanded condition comprising the steps of:

(a) forming a plurality of pockets in a first continuous plastic sheet, said pockets being aligned in a staggered series;

(b) introducing measured amounts of said first component into each pocket;

(c) placing a time release capsule containing said first component, and a rupturable plastic enclosure on said first continuous sheet containing a solvent medium and said second component;

(d) placing a second plastic sheet over said first continuous group of pockets and releasably sealing it at least at its marginal areas to said first sheet;

(e) permanently sealing a third plastic sheet to said first continuous sheet at the marginal areas of both and to said second sheet to provide a bag-like enclosure containing within its interior all of said compartments, said second sheet and said enclosure;

(f) forming successive bags in said first continuous sheet;

(g) winding said continuous sheet containing the formed bags into a supply roll having a delivery end presenting a first bag;

(h) positioning the body of said container adjacent said supply roll;

(i) breaking said rupturable enclosure in the bag at said delivery end to bring its contents into contact with said time release capsule;

(j) severing the bag in step (i) from said roll and inserting said bag into said container;

(k) introducing said liquid product into said container; and

(l) affixing a top with associated dispensing means on said container to enclose the same.

9. In the method of claim 8, heating said container sufficiently to enhance activation of the admixture of said time release capsule and said second component in said solvent medium.

11. In the method of claim 8, step (d) including releasably sealing said second sheet to said first sheet in a plurality of relatively short angular guard seals adjacent said pockets and step (e) including permanently sealing said second and third sheets together in an elongated separation seal running generally longitudinally and centrally of said bag.

12. The method of assembling an aerosol-type container for dispensing a liquid product on demand in which the internal pressurizing means in said container is a fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing said bag to expand gradually from a collapsed condition to an ultimate fully expanded condition comprising the steps of:

(a) providing a supply roll containing the formed bags and having a delivery end presenting a first bag, each of said bags having a time release capsule and a rupturable enclosure containing a solvent medium therein;

(b) positioning the body portion of said aerosol-type container adjacent said supply roll;

(c) breaking said rupturable enclosure in the bag at said delivery end to bring its contents into contact with said time release capsule;

(d) severing the bag in step (c) from said roll and inserting said bag into said container;

(e) introducing said liquid product into said container; and

(f) affixing a top with associated dispensing means on said container to enclose the same.

13. In the method of claim 12, heating said container sufficiently to enhance activation of the admixture of said time release capsule and the second gas generating component in said solvent medium.

14. A method of assembling an aerosol-type container for dispensing a liquid product on demand in which the internal pressurizing means in said container is a fluid impervious expandable enclosed bag containing separately compartmental first and second gas generating components which, upon admixture in successive amounts, generate gas causing said bag to expand gradually from a collapsed condition to an ultimate fully expanded condition comprising the steps of:

(a) routing said aerosol-type containers along a predetermined path to an insertion station;

(b) feeding a supply roll of said expandable enclosed bags to the insertion station;

(c) breaking one of said compartmented gas generating components to release its contents and permit contact with the other of said gas generating components;

(d) severing the individual bag from said supply roll;

(e) inserting the severed bag into said aerosol type container;

(f) introducing the liquid product into the container; and

(g) affixing a top on said container thereby enclosing the same.

15. The method of claim 14 which further includes the steps of providing a time release capsule in said bag and routing said aerosol container with bag inserted therein to a heated medium to activate the time release capsule and the gas generating components.