# US 5,776,388 A · Methods for molding articles which include a hinged starch-bound cellular matrix

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- Number: US 5,776,388 A
- Document ID: US5776388A
- Status: Granted
- Kind: A
- Application number: 08/661,224
- Filed: 1996-06-10
- Granted: 1998-07-07
- Earliest claimed: 1994-02-07
- Assignees: E. Khashoggi Industries
- Inventors: Per Just Andersen; Simon K. Hodson
- Web page: https://patentgrep.com/patent/US5776388A

## CPC

- C08J 9/365: {Coating}
- B27N 3/002: {characterised by the type of binder (compositions of macromolecular compounds C08L)}
- B27N 3/007: {and at least partly composed of recycled material}
- B28B 1/00: Producing shaped {prefabricated} articles from the material (using presses B28B3/00; shaping on moving conveyors B28B5/00; producing tubular articles B28B21/00 {; producing articles with embedded elements B28B23/00})
- B28B 1/52: specially adapted for producing articles from mixtures containing fibres, {e.g. asbestos cement}(by wrapping on to mandrels B28B1/42)
- B28B 3/126: {on material passing directly between the co-operating rollers}
- B28B 3/20: wherein the material is extruded {(extrusion moulding of plastics B29C48/00)}
- B28B 11/00: Apparatus or processes for treating or working the shaped {or preshaped} articles (specially adapted for tubular articles B28B21/92; decoration or surface treatment in general B05, B44; compacting concrete in situ in connection with building E04G21/06; drying F26)
- B28B 11/003: {the shaping of preshaped articles, e.g. by bending (B28B11/08 takes precedence)}
- B28B 23/0081: {Embedding aggregates to obtain particular properties}
- B29C 33/36: continuously movable {in one direction, e.g. in a closed circuit (B29C49/0021 takes precedence)}
- B29C 39/003: {characterised by the choice of material}
- B29C 39/42: Casting under special conditions, e.g. vacuum
- B29C 43/003: {characterised by the choice of material}
- B29C 43/06: continuously movable {in one direction, e.g. mounted on chains, belts}
- B29C 43/34: Feeding the material to the mould or the compression means {(B29C43/085 takes precedence)}
- B29C 43/36: Moulds for making articles of definite length, i.e. discrete articles
- B29C 44/0407: {by regulating the temperature of the mould or parts thereof, e.g. cold mould walls inhibiting foaming of an outer layer}
- B29C 44/3402: {Details of processes or apparatus for reducing environmental damage or for working-up compositions comprising inert blowing agents or biodegradable components}
- B29C 45/0013: {using fillers dispersed in the moulding material, e.g. metal particles}
- B29C 51/002: {characterised by the choice of material}
- B29C 55/18: by squeezing between surfaces, e.g. rollers
- B29C 67/202: {comprising elimination of a solid or a liquid ingredient}
- B29C 67/24: characterised by the choice of material
- B29C 67/242: {Moulding mineral aggregates bonded with resin, e.g. resin concrete (shaping ceramic compositions without binder or water-setting cementitious material B28B; compositions per se C04B)}
- B29C 70/025: {with particular filler}
- B29C 70/12: using fibres of short length, e.g. in the form of a mat {(non-woven fabrics per se D04H1/00)}
- B29C 71/0009: {using liquids, e.g. solvents, swelling agents (spectacle cases, e.g. for cleaning contact lenses A45C11/04; disinfecting or sterilising contact lenses A61L12/00, using liquid substances A61L2/20; cleaning involving the use of liquid in general B08B3/00; for hydrating contact lenses B29D11/00067)}
- B32B 5/02: characterised by structural features of a {fibrous or filamentary} layer {(layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02)}
- B32B 5/14: characterised by a layer differing constitutionally or physically in different parts, e.g. denser near its faces
- B32B 5/18: characterised by features of a layer {of} foamed material
- B32B 9/00: Layered products comprising a {layer of a} particular substance not covered by groups B32B11/00 - B32B29/00
- B32B 13/02: with fibres or particles {being present as additives in the layer}
- B32B 27/04: as impregnant, bonding, or embedding substance {(not used)}
- B32B 27/20: using fillers, pigments, thixotroping agents
- B65D 43/162: {the container, the lid and the hinge being made of one piece (B65D43/161 takes precedence)}
- B65D 65/466: {Bio- or photodegradable packaging materials}
- C04B 26/28: Polysaccharides or derivatives thereof
- C08J 5/18: Manufacture of films or sheets
- C08J 9/0085: {Use of fibrous compounding ingredients (C08J9/0076 takes precedence)}
- C08J 9/12: by a physical blowing agent
- C08J 9/28: by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
- C08L 3/00: Compositions of starch, amylose or amylopectin or of their derivatives or degradation products
- C08L 3/02: Starch; Degradation products thereof, e.g. dextrin
- E05D 1/02: made of one piece
- B05C 5/0245: {for applying liquid or other fluent material to a moving work of indefinite length, e.g. to a moving web (B05C5/0241, B05C5/0254, B05C5/027, B05C5/0283 take precedence)}
- B29C 33/04: using liquids, gas or steam {(tyre moulds with incorporated heating or cooling means using liquids, gas or steam B29D30/0601)}
- B29C 33/10: with incorporated venting means
- B29C 33/20: Opening, closing or clamping
- B29C 43/00: Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor {(by liberation of internal stresses B29C61/006)}
- B29C 43/08: with circular movement {, e.g. mounted on rolls, turntables}
- B29C 2043/3433: {using dispensing heads, e.g. extruders, placed over or apart from the moulds}
- B29C 2043/5841: {for accommodating variation in mould spacing or cavity volume during moulding}
- B29K 2003/00: Use of starch or derivatives as moulding material
- B29K 2105/0064: {Latex, emulsion or dispersion}
- B29K 2105/04: cellular or porous
- B29K 2105/06: containing reinforcements, fillers or inserts
- B29K 2105/16: Fillers
- B29K 2995/0059: Degradable
- B29L 2031/712: {Containers; Packaging elements or accessories, Packages (closures therefor B29L2031/56; ink or toner cartridges B29L2031/7678; squeeze tubes B29L2023/20; suitcases B29L2031/7418)}
- B65D 2565/385: especially suited for or with means facilitating recycling
- C04B 2111/00094: {Sag-resistant materials}
- C04B 2111/0062: {Gypsum-paper board like materials}
- C08J 2201/0504: the liquid phase being aqueous
- C08J 2303/00: Characterised by the use of starch, amylose or amylopectin or of their derivatives or degradation products
- C08J 2323/02: not modified by chemical after treatment
- E05Y 2999/00: Subject-matter not otherwise provided for in this subclass
- Y02W 90/10: Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- B27N: MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL (containing cementitious material B28B; shaping of substances in a plastic state B29C; fibreboards made from fibrous suspensions D21J; drying F26B17/00)
- B28B: SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B22C; working stone or stone-like material B28D; shaping of substances in a plastic state, in general B29C; making layered products not composed wholly of these substances B32B)
- 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 (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00)
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- 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
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE
- C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06)
- E05D: HINGES OR SUSPENSION DEVICES FOR DOORS, WINDOWS OR WINGS (pivotal connections in general F16C11/00)
- B05C: APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (spraying apparatus, atomising apparatus, nozzles B05B; plant for applying liquids or other fluent materials to objects by electrostatic spraying B05B5/08)
- 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
- B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- E05Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES E05D AND E05F, RELATING TO CONSTRUCTION ELEMENTS, ELECTRIC CONTROL, POWER SUPPLY, POWER SIGNAL OR TRANSMISSION, USER INTERFACES, MOUNTING OR COUPLING, DETAILS, ACCESSORIES, AUXILIARY OPERATIONS NOT OTHERWISE PROVIDED FOR, APPLICATION THEREOF
- Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT

## Abstract

Methods and systems for forming hinged starch-bound matrices. Starch-based compositions are molded between heated molds in order to form a cellular matrix and also to remove the water from the starch-based compositions in order to form a binding matrix of solidified starch. The molding apparatus is configured to form one or more creases within the hinge area in order to define one or more lines upon which the hinge will bend. The molding apparatus is also configured such that the region of the mold corresponding to the inner surface of the hinge area will transfer heat more slowly to the inner hinge surface, resulting in reduced thickness of the skin of the inner hinge. This increases the collapsibility, or ability of the inner surface of the hinge to fold or buckle, during the bending action. This in turn reduces the bending radius of hinge such that the hinging action exerts less strain on the outer surface of the hinge. The inner surface of the hinge may optionally be treated with glycerin or other polyols to soften the inner surface. The outer surface of the hinge may optionally be coated with an elastomeric material, such as polyvinyl alcohol, in order to strengthen the outer surface and reduce its tendency to fracture during the hinging action.

## Claims

### Claim 1

A method for manufacturing an article having a starch-bound cellular matrix, the method comprising:
molding an aqueous starch-based mixture into a desired shape of the article under elevated temperature in order to remove a substantial portion of the water from the mixture by evaporation and thereby form the starch-bound cellular matrix of the article, the molding step including forming a hinge structure within the article, the hinge structure comprising an interior skin portion, an exterior skin portion, and an interior cellular core disposed between the interior skin portion and the exterior skin portion, the interior cellular core having a density less than the densities of the interior and exterior skin portions; and
demolding the article after the article has achieved form stability.

### Claim 2 (depends on 1)

A method for manufacturing an article as defined in claim 1, wherein the molding step includes forming at least one depression in the interior skin portion of the hinge structure.

### Claim 3 (depends on 1)

A method for manufacturing an article as defined in claim 1, wherein the molding step results in the interior skin portion having a thickness that is less than the thickness of the exterior skin portion.

### Claim 4 (depends on 1)

A method for manufacturing an article as defined in claim 1, wherein the molding step imparts less heat per unit time to the interior skin portion of the hinge structure than to the exterior skin portion of the hinge structure such that the interior skin portion is formed having a thickness that is less than the thickness of the exterior skin portion.

### Claim 5

A method for manufacturing an article having a starch-bound cellular matrix, the method comprising:
molding an aqueous starch-based mixture into a desired shape of the article under elevated temperature in order to remove a substantial portion of the water from the mixture by evaporation, thereby forming the starch-bound cellular matrix of the article, the molding step including forming a hinge structure within the article, wherein the hinge structure comprises an interior skin portion, an exterior skin portion, an interior cellular core disposed between the interior skin portion and the exterior skin portion, and at least one depression in the interior skin portion, the molding step resulting in the interior skin portion of the hinge structure having a thickness that is less than the thickness of the exterior skin portion of the hinge structure; and
demolding the article after the article has achieved form stability.

### Claim 6 (depends on 5)

A method for manufacturing an article as defined in claim 5, wherein the molding step imparts less heat per unit time to the interior skin portion of the hinge structure than to the exterior skin portion of the hinge structure such that the interior skin portion is formed having a thickness that is less than the thickness of the exterior skin portion.

### Claim 7 (depends on 5)

A method for manufacturing an article as defined in claim 5, wherein the molding step is carried out using a heated mold apparatus.

### Claim 8 (depends on 7)

A method for manufacturing an article as defined in claim 7, wherein the heated mold apparatus includes a molding strip corresponding to the interior skin portion of the hinge structure and having reduced heat diffusivity compared to the rest of the mold apparatus.

### Claim 9 (depends on 5)

A method for manufacturing an article as defined in claim 5, wherein the molding step yields a multiple hinge having at least two depressions in the interior skin portion of the hinge structure.

### Claim 10 (depends on 5)

A method for manufacturing an article as defined in claim 5, wherein the molding step results in the exterior skin portion of the hinge structure having at least one bending initiation groove.

### Claim 11 (depends on 5)

A method for manufacturing an article as defined in claim 5, further including the step of treating the interior skin portion of the hinge structure with a polyol.

### Claim 12 (depends on 11)

A method for manufacturing an article as defined in claim 11, wherein the polyol is applied by means of an aqueous polyol solution.

### Claim 13 (depends on 11)

A method for manufacturing an article as defined in claim 11, wherein the polyol comprises glycerin.

### Claim 14 (depends on 11)

A method for manufacturing an article as defined in claim 11, wherein the polyol is selected from the group consisting of polyethylene glycol, propylene glycol, polypropylene glycol, sorbitol, and mixtures of the foregoing.

### Claim 15 (depends on 5)

A method for manufacturing an article as defined in claim 5, further including the step of applying an elastomeric coating to the exterior skin portion of the hinge structure.

### Claim 16 (depends on 15)

A method for manufacturing an article as defined in claim 15, wherein the elastomeric coating comprises polyvinyl alcohol.

### Claim 17 (depends on 15)

A method for manufacturing an article as defined in claim 15, wherein the elastomeric coating is selected from the group consisting of polylactic acid, natural latex, derivatives of the foregoing, and mixtures of the foregoing.

### Claim 18

A method for manufacturing an article having a starch-bound cellular matrix, the method comprising:
molding an aqueous starch-based mixture into a desired shape of the article under elevated temperature in order to remove a substantial portion of the water from the mixture by evaporation, thereby forming the starch-bound cellular matrix of the article, the molding step including forming a hinge structure within the article, wherein the hinge structure comprises an interior skin portion, an exterior skin portion, an interior cellular core disposed between the interior skin portion and the exterior skin portion, and at least one depression in the interior skin portion, the molding step imparting less heat per unit time to the interior skin portion of the hinge structure than to the exterior skin portion of the hinge structure such that the interior skin portion is formed having a thickness that is less than the thickness of the exterior skin portion; and
demolding the article after the article has achieved form stability.

### Claim 19 (depends on 18)

A method for manufacturing an article as defined in claim 18, wherein the molding step yields a multiple hinge having at least two depressions in the interior skin portion of the hinge structure.

### Claim 20 (depends on 18)

A method for manufacturing an article as defined in claim 18, wherein the molding step results in the exterior skin portion of the hinge structure having at least one bending initiation groove.

### Claim 21 (depends on 18)

A method for manufacturing an article as defined in claim 18, further including the step of treating the interior skin portion of the hinge structure with a polyol.

### Claim 22 (depends on 21)

A method for manufacturing an article as defined in claim 21, wherein the polyol is applied by means of an aqueous polyol solution.

### Claim 23 (depends on 21)

A method for manufacturing an article as defined in claim 21, wherein the polyol comprises glycerin.

### Claim 24 (depends on 21)

A method for manufacturing an article as defined in claim 21, wherein the polyol is selected from the group consisting of polyethylene glycol, propylene glycol, polypropylene glycol, sorbitol, and mixtures of the foregoing.

### Claim 25 (depends on 18)

A method for manufacturing an article as defined in claim 18, further including the step of applying an elastomeric coating to the exterior skin portion of the hinge structure.

### Claim 26 (depends on 25)

A method for manufacturing an article as defined in claim 25, wherein the elastomeric coating comprises polyvinyl alcohol.

### Claim 27 (depends on 25)

A method for manufacturing an article as defined in claim 25, wherein the elastomeric coating is selected from the group consisting of polylactic acid, natural latex, derivatives of the foregoing, and mixtures of the foregoing.

### Claim 28 (depends on 18)

A method for manufacturing an article as defined in claim 18, further including the step of applying a wax-based coating material to the article.

### Claim 29 (depends on 18)

A method for manufacturing an article as defined in claim 18, wherein the molding step yields a clam shell container.

### Claim 30

A method for manufacturing an article having a starch-bound cellular matrix, the method comprising:
molding an aqueous starch-based mixture within a heated mold apparatus into a desired shape of the article under elevated temperature in order to remove a substantial portion of the water from the mixture by evaporation, thereby forming the starch-bound cellular matrix of the article, the heated mold forming a hinge structure within the article, wherein the hinge structure comprises an interior skin portion, an exterior skin portion, an interior cellular core disposed between the interior skin portion and the exterior skin portion, and at least one depression in the interior skin portion, the heated mold being configured such that it imparts less heat per unit time to the interior skin portion of the hinge structure than to the exterior skin portion of the hinge structure such that the interior skin portion is formed having a thickness that is less than the thickness of the exterior skin portion; and
demolding the article after the article has achieved form stability.

### Claim 31 (depends on 30)

A method for manufacturing an article as defined in claim 30, wherein the molding step yields a multiple hinge having at least two depressions in the interior skin portion of the hinge structure.

### Claim 32 (depends on 30)

A method for manufacturing an article as defined in claim 30, wherein the molding step results in the exterior skin portion of the hinge structure having at least one bending initiation groove.

### Claim 33 (depends on 30)

A method for manufacturing an article as defined in claim 30, further including the step of treating the interior skin portion of the hinge structure with a polyol.

### Claim 34 (depends on 33)

A method for manufacturing an article as defined in claim 33, wherein the polyol is applied by means of an aqueous polyol solution.

### Claim 35 (depends on 33)

A method for manufacturing an article as defined in claim 33, wherein the polyol comprises glycerin.

### Claim 36 (depends on 33)

A method for manufacturing an article as defined in claim 33, wherein the polyol is selected from the group consisting of polyethylene glycol, propylene glycol, polypropylene glycol, sorbitol, and mixtures of the foregoing.

### Claim 37 (depends on 30)

A method for manufacturing an article as defined in claim 30, further including the step of applying an elastomeric coating to the exterior skin portion of the hinge structure.

### Claim 38 (depends on 37)

A method for manufacturing an article as defined in claim 37, wherein the elastomeric coating comprises polyvinyl alcohol.

### Claim 39 (depends on 37)

A method for manufacturing an article as defined in claim 37, wherein the elastomeric coating is selected from the group consisting of polylactic acid, natural latex, derivatives of the foregoing, and mixtures of the foregoing.

### Claim 40 (depends on 30)

A method for manufacturing an article as defined in claim 30, further including the step of applying a wax-based coating material to the article.

### Claim 41 (depends on 30)

A method for manufacturing an article as defined in claim 30, wherein the molding step yields a clam shell container.