EP1594915A2 - Starch-loaded polyvinyl alcohol copolymer film for packaging non-liquid product and method for making the same - Google Patents
Starch-loaded polyvinyl alcohol copolymer film for packaging non-liquid product and method for making the sameInfo
- Publication number
- EP1594915A2 EP1594915A2 EP20040710619 EP04710619A EP1594915A2 EP 1594915 A2 EP1594915 A2 EP 1594915A2 EP 20040710619 EP20040710619 EP 20040710619 EP 04710619 A EP04710619 A EP 04710619A EP 1594915 A2 EP1594915 A2 EP 1594915A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- percent
- film
- copolymer
- range
- weight
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
- B65D65/38—Packaging materials of special type or form
- B65D65/46—Applications of disintegrable, dissolvable or edible materials
-
- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W90/00—Enabling technologies or technologies with a potential or indirect contribution to greenhouse gas [GHG] emissions mitigation
- Y02W90/10—Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics
Definitions
- the present invention relates generally to water-soluble polyvinyl alcohol (PVOH) film. More specifically, the present invention relates to water-soluble PVOH film with particular applications for packaging of non-liquid products, such as cleansers, conditioners, disinfectants, and the like.
- PVOH polyvinyl alcohol
- Polyvinyl alcohol is a synthetic resin generally prepared by the alcoholysis, usually termed hydrolysis or saponification, of polyvinyl acetate.
- Fully hydrolyzed PVOH where virtually all the acetate groups have been converted to alcohol groups, is a strongly hydrogen-bonded, highly crystalline polymer which dissolves only in hot water — greater than about 140° F (60° C). If a sufficient number of acetate groups are allowed to remain after the hydrolysis of polyvinyl acetate, the PVOH polymer then being known as partially hydrolyzed, it is more weakly hydrogen- bonded and less crystalline and is soluble in cold water — less than about 50° F (10° C). Both fully and partially hydrolyzed PVOH types are commonly referred to as PVOH homopolymers although the partially hydrolyzed type is technically a vinyl alcohol- vinyl acetate copolymer.
- PVOH copolymer is generally used to describe polymers that are derived by the hydrolysis of a copolymer of a vinyl ester, typically vinyl acetate, and another monomer. PVOH copolymers can be tailored to desired film characteristics by varying the kind and quantity of copolymerized monomers. Examples of copolymerizations are those of vinyl acetate with a carboxylic acid or with an ester of a carboxylic acid. Again, if the hydrolysis of acetate groups in these copolymers is only partial, then the resulting polymer could be described as a PVOH te ⁇ olymer — having vinyl acetate, vinyl alcohol, and carboxylic acid groups — although it is commonly referred to as a copolymer.
- the present invention has solved this problem of film quality versus manufacturing cost as it relates to packaging of powdered product, as well as other problems faced by those in the industry.
- a water-soluble film suitable for packaging a non-liquid product including the method for preparing the film composition and packaging for the non- liquid product, is disclosed.
- the film combination comprises a hydrolyzed copolymer of vinyl acetate and methyl acrylate in the range of from about 30 to about 95 percent by weight, modified starch in the range of from about 4 to about 30 percent by weight, plasticizer in the range of from about 5 to about 30 percent by weight, lubricant/release agent in the range of from about 0.0 or about 0.01 to about 1.5 percent by weight, and surfactant in the range of from about 0.01 to about 1.5 percent by weight.
- the film composition utilizes a bleaching agent to prevent color drift, such as browning, of a polymer solution used to cast the film.
- a bleaching agent to prevent color drift, such as browning, of a polymer solution used to cast the film.
- Oxidizing bleaching agents e.g., chlorine, chlorinated compounds, oxygen, and oxygenated compounds
- reducing bleaching agents e.g., hydrosulfites, borohydrides, and metabisulfites
- Examples include sodium percarbonate, sodium persulfate, peracetic acid, sodium hydrosulfite and sodium metabisulfite. Sodium percarbonate and sodium metabisulfite are preferred, and sodium metabisulfite is most preferred.
- the agent comprises sodium metabisulfite in an amount in the range of from about 0.12 to about 1.0 percent by weight. Most preferably, the sodium metabisulfite is used in an amount in the range of from about 0.4 to about 0.7 percent by weight.
- a preferred method for preparing a water-soluble copolymer film for packaging of a non-liquid product comprises the steps of copolymerizing vinyl acetate and methyl acrylate to form a copolymer, hydrolyzing the vinyl acetate-methyl acrylate copolymer to form a vinyl alcohol-gamma lactone copolymer having a 4% solution viscosity in the range of from about 5 to about 50 cps at 20° C, slurrying the hydrolyzed polymer with water, adding modified starch to the copolymer-water slurry in an amount of from about 4.0 to about 25.0 percent by weight, heating the hydrolyzed copolymer and starch slurry to form a solution, treating the solution with caustic soda to create a solution of a copolymer having from about 1 to about 12 mol percent carboxylate groups, from about 0 to about 11 mol percent gamma lactone units, and from about 88 to about 99 mol percent vinyl
- a package for containing a non-liquid product comprises at least one compartment comprised of a water-soluble film comprising from about 30 to about 95 percent by weight of a hydrolyzed copolymer of vinyl acetate and methyl acrylate, from about 4 to about 30 percent by weight of modified starch filler, from about 5 to about 30 percent by weight of plasticizer, and from about 0.01 to about 1.5 percent by weight of a surfactant.
- the package may be used to deliver a unit dose of a non-liquid agent.
- the preferred unit dose comprises a package comprising a water- soluble film comprising from about 40 to about 90 percent by weight of a hydrolyzed copolymer of vinyl acetate and methyl acrylate, from about 4 to about 30 percent by weight of a modified starch filler, from about 5 to about 30 percent by weight of a plasticizer, and from about 0.01 to about 1.0 percent by weight of a surfactant, and a non-liquid agent contained within the package.
- the non-liquid agent may be a cleanser, a disinfectant, a polish, a conditioner, or the like.
- FIGURE 1 is a perspective view of a test apparatus used to analyze the water disintegration and dissolution of film samples
- FIGURE 2 is a perspective view of the test apparatus and test set-up illustrating the procedure for analyzing the water-solubility of film samples; and
- FIGURE 3 is a top view of the test set-up of FIGURE 2.
- Non-liquid shall refer to any product that has as a component a form characteristic of a solid, including but not limited to powder, caked, shaving, solid, gel, slurry, paste, pelletized, and the like.
- Package or “packaging” shall refer to any receptacle or method suitable for holding or enclosing, to a substantial degree, a quantity of non-liquid product, without regard to size, shape, or the number of parts used to form the container or carry out the method.
- the film is based on an amount of a hydrolyzed copolymer of vinyl acetate and methyl acrylate and is a vinyl alcohol-gamma lactone copolymer, in the range of from about 30 to about 95 percent by weight. Preferably, the amount of copolymer is in the range of from about 50 to about 85 percent by weight.
- the copolymer may be prepared in any manner known by those skilled in the art. A particularly suitable copolymer is sold by E.I. duPont de Nemours under the tradename ELVANOL.
- the ELVANOL range of water-soluble synthetic polymers has excellent film-forming, emulsifying, and adhesive properties. Such polymers offer resistance to oil, grease and solvents, plus high tensile strength, flexibility, and high oxygen barrier.
- a vinyl acetate-methyl acrylate copolymer must first undergo hydrolysis (also called alcoholysis) to form a vinyl alcohol-gamma lactone copolymer.
- the vinyl alcohol-gamma lactone copolymer preferably has a 4% solution viscosity in the range of from about 5 to about 50 cps (0.005 to 0.050 pascal seconds) at 20° C (68° F).
- the vinyl alcohol- gamma lactone copolymer has a 4% solution viscosity in the range of from about 8 to about 35 cps (0.008 to 0.035 pascal seconds) and, most preferably, the vinyl alcohol- gamma lactone copolymer has a 4% solution viscosity in the range of from about 15 to about 25 cps (0.015 to 0.025 pascal seconds).
- the hydrolyzed copolymer initially comprises an amount of gamma lactone units preferably from about 2 to about 12 mol percent, more preferably from about 4 to about 6 mol percent.
- Modified starch is added to the hydrolyzed copolymer, which preferably is first slurried with water, in an amount in the range of from about 4 to about 30 percent by weight, preferably about 4 to about 12 percent by weight. While other modified starches may be suitable, the preferred modified starch is hydroxyethyl modified starch in an amount of about 10 percent by weight, hi another embodiment, the amount of starch is at least 5 percent by weight.
- the composition also comprises plasticizer, such as in the range of from about 5 to about 30 percent by weight, preferably about 10 to about 20 percent by weight, or preferably in the range of from about 20 to about 30 percent by weight when sorbitol is present as a plasticizer.
- plasticizer such as in the range of from about 5 to about 30 percent by weight, preferably about 10 to about 20 percent by weight, or preferably in the range of from about 20 to about 30 percent by weight when sorbitol is present as a plasticizer.
- the composition also preferably comprises lubricant/release agent in the range of from about 0.0 to about 1.5 percent by weight, and surfactant in the range of from about 0.01 to about 1.5 percent by weight.
- lubricant/release agent in the range of from about 0.0 to about 1.5 percent by weight
- surfactant in the range of from about 0.01 to about 1.5 percent by weight.
- suitable components such as additional plasticizers, lubricants, and release agents, fillers, extenders, antiblocking agents, detackifying agents, antifoams and other functional ingredients, may be added in proper amounts to achieve a desired effect to the extent such components do not inhibit other desired characteristics of the copolymer film.
- the copolymer solution preferably is treated with caustic soda (sodium hydroxide), to yield a copolymer solution having from about 1 to about 12 mol percent, preferably from about 2 to about 6 mol percent, and most preferably from about 3 to about 4 mol percent carboxylate groups, from 0 to about 11 mol percent, preferably from 0 to about 5 mol percent, and most preferably from about 1 to about 2 mol percent gamma lactone units, and from about 88 to 99 mol percent, preferably from about 92 to about 98 mol percent, and most preferably from about 94 to about 96 mol percent vinyl alcohol units.
- caustic soda sodium hydroxide
- the copolymer solution is then cast to create a film having a thickness in the range of from about 0.5 mils to about 5.0 mils (about 0.013 to about 0.127 mm).
- the film thickness can have a direct effect on the speed at which the final product will dissolve in water, with thin films (e.g., less than 3.0 mil or 0.076 mm) completely dissolving in less time.
- thinner films typically provide less structural protection than their thicker film counte ⁇ arts. A balance must be struck between these and other factors.
- a preferable film thickness is in the range of from about 0.5 to about 3.0 mils (about 0.013 to about 0.076 mm), and most preferably in the range of from about 1.0 to about 2.0 mils (about 0.025 to about 0.050 mm).
- a browning effect can occur. It is desirable in most applications that the water-soluble film have a clear and colorless appearance. To combat this, and any other known color drift to which the copolymer solution may be susceptible, a suitable bleaching agent can be added to the copolymer solution.
- the use of sodium metabisulfite has been found to substantially maintain the solution clarity and colorlessness during preparation when used in an amount in the range of from about 0.12 to about 1.0 percent by weight, most preferably in an amount from about 0.4 to about 0.7 percent by weight.
- Suitable plasticizers include, but are not limited to, glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols and ethanolamines.
- Preferred plasticizers are glycerin, triethyleneglycol, propylene glycol and trimethylolpropane.
- Suitable surfactants may include the nonionic, cationic, anionic and zwitterionic classes.
- the surfactants will be of the nonionic, cationic or zwitterionic classes or combinations of these.
- Suitable surfactants include, but are not limited to, polyoxyethylenated polyoxypropylene glycols, alcohol ethoxylates, alkylphenol ethoxylates, tertiary acetylenic glycols and alkanolamides (nonionics), polyoxyethylenated amines, quaternary ammonium salts and quaternized polyoxyethylenated amines (cationics), and amine oxides, N-alkylbetaines and sulfobetaines (zwitterionics).
- Preferred surfactants are alcohol ethoxylates, quaternary ammonium salts and amine oxides.
- Suitable lubricants/release agents include, but are not limited to, fatty acids and their salts, fatty alcohols, fatty esters, fatty amines, fatty amine acetates and fatty amides.
- Preferred lubricants/release agents are fatty acids, fatty acid salts, and fatty amine acetates.
- Suitable fillers/extenders/antiblocking agents/detackifying agents include, but are not limited to, starches, modified starches, crosslinked polyvinylpyrrolidone, crosslinked cellulose, microcrystalline cellulose, silica, metallic oxides, calcium carbonate, talc and mica.
- Preferred materials are starches, modified starches and silica. If used, the preferred amount of such filler/extender/antiblocking agent/detackifying agent in the water-soluble film of the present invention is between 0.1% and 25% by weight, more preferably between 1 % and 15% by weight, and preferably between 1% and 5% by weight if starch is absent.
- Suitable antifoams include, but are not limited to, those based on polydimethylsiloxanes and hydrocarbon blends. If used, the preferred amount of antifoam in the water-soluble film of the present invention is between 0.001% and 0.5%, more preferably between 0.01 % and 0.1 % by weight.
- the preferred method for preparing the water-soluble copolymer film comprises the steps of copolymerizing vinyl acetate and methyl acrylate to form a copolymer.
- this vinyl acetate-methyl acrylate copolymer may be more readily purchased.
- the next steps include hydrolyzing the vinyl acetate- methyl acrylate copolymer to form a vinyl alcohol-gamma lactone copolymer having a 4% solution viscosity in the range of from about 5 to about 50 cps at 20°C, and slurrying the hydrolyzed polymer with water while adding modified starch to the copolymer-water slurry in an amount of from about 4.0 to about 25.0 percent by weight.
- the amount of modified starch is about 4 to about 12 percent by weight.
- the hydrolyzed copolymer and starch slurry is then heated to boiling point to form a solution.
- the solution is then treated with caustic soda to create a solution of a copolymer having from about 1 to about 12 mol percent carboxylate groups, from about 0 to about 11 mol percent gamma lactone units, and from about 88 to about 99 mol percent vinyl alcohol units. More preferable ranges have been previously stated.
- the next step is maintaining the solution at a temperature in the range of from about 160° F to about 200° F (about 71°C to about 93 °C), and then casting the hot copolymer solution on a suitable surface to create a film having a thickness in the range of from about 0.1 to about 5.0 mils (about 0.0025 to about 0.127mm).
- the method can further comprise the step of adding a bleaching agent, such as sodium metabisulfite, in an amount greater than 0.12 percent by weight to substantially reduce or prevent browning of the heated solution.
- a bleaching agent such as sodium metabisulfite
- a bisulfite is added in the amount of from about 0.4 to about 0.7 percent by weight.
- the resulting film can then be formed into a package for containing a non-liquid product, as previously described.
- Steps for forming a suitable package are known by those skilled in the art for similar handling films, or can be derived without undue experimentation.
- a preferred requirement of the film, and therefore the formed package is that it be capable of complete dissolution in water in a relatively short period of time.
- a preferred film of the present invention at a thickness of about 1.5 mil (about 0.038 mm), dissolves in water at a temperature of about 20°C in less than 60 seconds.
- Method 205 is used to determine the time required for a water-soluble film to break apart (disintegrate) and its subsequent relative dissolution time when held stationary. The test procedure is disclosed with reference to drawing FIGURES 1-3.
- Thermometer (0 to 100° C, ⁇ 1° C)
- test specimens from film sample using stainless steel template (i.e., 3.8 cm x 3.2 cm specimen). If cut from a film web, specimens should be cut from areas of web evenly spaced along the transverse direction of the web.
- the results should include the following:
- a unit dose of a non-liquid agent contained within the formed package does not necessarily pose the same packaging problems as a liquid product. With respect to the use of such a unit dose, however, no procedural changes are required. That is, merely adding the unit dose package to the appropriate quantity of water and following the necessary stirring or agitation times yields the desired cleaning, conditioning, or disinfectant solution.
Abstract
Description
Claims
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US367050 | 1982-04-09 | ||
US722637 | 1991-06-28 | ||
US10/367,050 US6821590B2 (en) | 2003-02-14 | 2003-02-14 | Starch-loaded polyvinyl alcohol copolymer film |
US10/722,637 US7005168B2 (en) | 2003-02-14 | 2003-11-26 | Starch-loaded polyvinyl alcohol copolymer film for packaging non-liquid product and method for making the same |
PCT/US2004/004048 WO2004074351A2 (en) | 2003-02-14 | 2004-02-12 | Starch-loaded polyvinyl alcohol copolymer film for packaging non-liquid product and method for making the same |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1594915A2 true EP1594915A2 (en) | 2005-11-16 |
Family
ID=32911917
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20040710619 Withdrawn EP1594915A2 (en) | 2003-02-14 | 2004-02-12 | Starch-loaded polyvinyl alcohol copolymer film for packaging non-liquid product and method for making the same |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1594915A2 (en) |
AU (1) | AU2004213383B2 (en) |
CA (1) | CA2517716C (en) |
WO (1) | WO2004074351A2 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101203551B (en) | 2005-06-16 | 2011-09-28 | 日本合成化学工业株式会社 | Water-solubility membrane |
CN107075152B (en) | 2014-11-28 | 2020-09-22 | 株式会社可乐丽 | Silage film, feed package, and feed storage method |
TW201829600A (en) * | 2016-10-27 | 2018-08-16 | 美商摩諾索公司 | Water-soluble film with low coefficient of friction |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2649403B1 (en) * | 1989-07-05 | 1991-10-25 | Lenigen Norbert | POLYVINYL ALCOHOL FILM HAVING IMPROVED SOLUBILITY CHARACTERISTICS |
US5272191A (en) * | 1991-08-21 | 1993-12-21 | Fmc Corporation | Cold water soluble films and film forming compositions |
US6387991B1 (en) * | 1995-12-18 | 2002-05-14 | E. I. Du Pont De Nemours & Company | Poly(vinyl alcohol) copolymer ionomers, their preparation and use in textile sizes |
-
2004
- 2004-02-12 AU AU2004213383A patent/AU2004213383B2/en not_active Ceased
- 2004-02-12 EP EP20040710619 patent/EP1594915A2/en not_active Withdrawn
- 2004-02-12 CA CA 2517716 patent/CA2517716C/en not_active Expired - Lifetime
- 2004-02-12 WO PCT/US2004/004048 patent/WO2004074351A2/en active Search and Examination
Non-Patent Citations (1)
Title |
---|
See references of WO2004074351A2 * |
Also Published As
Publication number | Publication date |
---|---|
CA2517716C (en) | 2009-06-02 |
CA2517716A1 (en) | 2004-09-02 |
AU2004213383A1 (en) | 2004-09-02 |
WO2004074351A2 (en) | 2004-09-02 |
WO2004074351A3 (en) | 2004-11-18 |
AU2004213383B2 (en) | 2008-08-14 |
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