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US 11,499,024 B2Granted
Method of manufacturing food packaging cellulosic films and food packaging cellulosic films thus produced
AssigneeViskase Companies, Inc.
InventorsMyron D. Nicholson, Francois Bargeot
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Abstract
The present invention relates to a method of manufacturing a cellulosic film (cellulose film), particularly a cellulosic food packing film, especially a detectable cellulosic film, which cellulosic film comprises detectable particles incorporated therein, as well as to the cellulosic film thus produced and to its applications and usages (i.e. its use).
Claims24
A detectable cellulosic food packaging film,
- wherein the detectable cellulosic food packaging film is made of at least one of a regenerated cellulose and a cellulose hydrate and comprises detectable particles incorporated therein in a homogeneous distribution;
- wherein the detectable particles:
- are magnetic,
- are detectable by a metal detection device,
- comprise at least one magnetic iron oxide selected from the group consisting of magnetite (Fe3O4), maghemite (Fe2O3), hematite (Fe2O3), ferrite, goethite (FeO(OH)), lepidocrocite (FeO(OH)) and ferroxyhyte (FeO(OH)) as well as mixtures and combinations thereof, and
- comprise a weight-related specific saturation magnetization of at least 50 Am2/kg iron (Fe);
- wherein the detectable particles comprise a hydrophobic surface-modification protective against oxygen and oxidation, wherein the surface-modification is bonded to the particle surfaces of the detectable particles and comprises inorganic, organic or inorganic-organic polymers selected from the group consisting of polysilanes, polysiloxanes, polyacrylates, polymethacrylates, polyacrylamides, starch-based polymers, cellulose-based polymers, polysaccharides, polyaminosaccharides and biopolymers as well as mixtures and combinations thereof;
- and
- wherein the cellulosic food packaging film comprises:
- (i) the at least one of regenerated cellulose and cellulose hydrate in amounts of from 70 to 99.4 wt. %, based on the overall weight of the cellulosic food packaging film comprising the detectable particles incorporated therein;
- (ii) the detectable particles in amounts of from 0.1 to about 30 wt. %, based on the overall weight of the cellulosic food packaging film comprising the detectable particles incorporated therein;
- (iii) at least one food-compatible plasticizer comprising a polyol and in amounts of from 0.5 to about 30 wt. %, based on the overall weight of the cellulosic film comprising the detectable particles incorporated therein;
- (iv) at least trace amounts of at least one dispersant selected from the group consisting of arylsulfonic acids-formaldehyde condensates;
- and
- (v) at least trace amounts of at least one rheology modifier, wherein the at least one rheology modifier is a cellulose derivative selected from the group consisting of carboxymethyl cellulose (CMC), methyl ethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, methyl cellulose, ethyl cellulose, cellulose powder, microcrystalline cellulose, and mixtures and combinations of any of the foregoing.
12 more elements
A detectable cellulosic food packaging film,
- wherein the detectable cellulosic food packaging film is made of at least one of a regenerated cellulose and a cellulose hydrate and comprises detectable particles incorporated therein in a homogeneous distribution, wherein the detectable particles:
- are magnetic,
- are detectable by a metal detection device,
- comprise at least one magnetic iron oxide selected from the group consisting of magnetite (Fe3O4), maghemite (Fe2O3), hematite (Fe2O3), ferrite, goethite (FeO(OH)), lepidocrocite (FeO(OH)) and ferroxyhyte (FeO(OH)) as well as mixtures and combinations thereof, and
- comprise a weight-related specific saturation magnetization of at least 50 Am2/kg iron (Fe);
- and
- wherein the cellulosic food packaging film comprises:
- (i) the at least one of regenerated cellulose and cellulose hydrate in amounts of from 70 to 99.4 wt. %, based on the overall weight of the cellulosic food packaging film comprising the detectable particles incorporated therein;
- (ii) the detectable particles in amounts of from 0.1 to about 30 wt. %, based on the overall weight of the cellulosic food packaging film comprising the detectable particles incorporated therein;
- (iii) at least one food-compatible plasticizer comprising a polyol and in amounts of from 0.5 to about 30 wt. %, based on the overall weight of the cellulosic film comprising the detectable particles incorporated therein;
- (iv) at least trace amounts of at least one dispersant selected from the group consisting of arylsulfonic acids-formaldehyde condensates;
- and
- (v) at least trace amounts of at least one rheology modifier selected from the group consisting of cellulose esters and cellulose ethers.
10 more elements
A detectable cellulosic food packaging film,
- wherein the detectable cellulosic food packaging film is made of at least one of a regenerated cellulose and a cellulose hydrate and comprises detectable particles incorporated therein in a homogeneous distribution;
- wherein the detectable particles:
- are magnetic,
- are detectable by a metal detection device,
- comprise at least one magnetic iron oxide selected from the group consisting of magnetite (Fe3O4), maghemite (Fe2O3), hematite (Fe2O3), ferrite, goethite (FeO(OH)), lepidocrocite (FeO(OH)) and ferroxyhyte (FeO(OH)) as well as mixtures and combinations thereof, and
- comprise a weight-related specific saturation magnetization of at least 50 Am2/kg iron (Fe);
- and
- wherein the film has been obtained by a method comprising the following steps:
- (i) a first step of introducing detectable particles into a solution or dispersion comprising at least one of a cellulose and a cellulose precursor or derivative in the presence of:
- at least one dispersant comprising a naphthalenesulfonic acid-formaldehyde condensate or a neutral salt thereof;
- and
- at least one rheology modifier selected from the group consisting of (i) carboxymethyl cellulose (CMC), methyl ethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, methyl cellulose, ethyl cellulose, cellulose powder, and microcrystalline cellulose;
- (ii) organic polymers selected from the group consisting of polyvinyl alcohols, polyacrylic acids and their salts, polyacrylates, polymethacrylic acids and their salts, polymethacrylates, polyacrylamides, polyvinylpyrrolidones, and polyalkylene glycols;
- (iii) alginic acids and their salts, ethers, and esters;
- (iv) agar (agar-agar);
- (v) carrageenans;
- (vi) ceratonia siliqua gums (locust bean gums);
- (vii) galactomannans;
- (viii) tragacanth gums;
- (ix) gum Arabic;
- (x) xanthan gums;
- (xi) gellan gums;
- (xii) polysaccharides and polysaccharide derivatives;
- and (xiii) mixtures and combinations of any of the foregoing;
- and
- (ii) followed by a second step of regenerating and recovering cellulose from the solution or dispersion in the presence of the detectable particles, so as to obtain the detectable cellulosic food packaging film comprising the detectable particles incorporated therein in homogeneous distribution.
23 more elements
Dependencies are inferred from the claim text.