METHOD OF MANUFACTURING FOOD PACKAGING CELLULOSIC FILMS AND FOOD PACKAGING CELLULOSIC FILMS THUS PRODUCED

• US 20190313655A1
• Filed: 10/03/2016
• Published: 10/17/2019
• Est. Priority Date: 10/03/2016
• Status: Active Grant

• Current Assignee: Viskase Companies Incorporated
• Original Assignee: Viskase Companies Incorporated
• Inventors: Nicholson, Myron D., Bargeot, Francois
• Granted Patent: US 11,499,024 B2
• Time in Patent Office: Days
• CPC Class Codes: A22C 13/0013 Chemical composition of synthetic sausage casings
• CPC Class Codes: A22C 2013/002 made by extrusion
• CPC Class Codes: A22C 2013/0036 with features allowing an easy opening and/or removal of the casing
• CPC Class Codes: A22C 2013/0073 seamless casings made out of a continuous seamless tubular sheet
• CPC Class Codes: A22C 2013/0096 cellulosic
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29K 2001/00 Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material
• CPC Class Codes: B29K 2505/12 Iron
• CPC Class Codes: B29K 2509/00 Use of inorganic materials not provided for in groups B29K2503/00 - B29K2507/00, as filler
• CPC Class Codes: B29K 2995/0008 Magnetic or paramagnetic
• CPC Class Codes: B29L 2031/7129 open
• CPC Class Codes: B32B 2264/102 Oxide or hydroxide
• CPC Class Codes: B32B 2264/30 Particles characterised by physical dimension
• CPC Class Codes: B32B 23/06 of paper or cardboard
• CPC Class Codes: B32B 23/08 of synthetic resin
• CPC Class Codes: B32B 23/10 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 23/14 characterised by containing special compounding ingredients
• CPC Class Codes: B32B 23/18 Fillers
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2307/718 : Weight, e.g. weight per square meter
• CPC Class Codes: B32B 2307/7244 : Oxygen barrier
• CPC Class Codes: B32B 2439/70 : Food packaging
• CPC Class Codes: C08J 2301/02 : Cellulose; Modified cellulose
• CPC Class Codes: C08J 2301/06 : Cellulose hydrate
• CPC Class Codes: C08J 2301/22 : Cellulose xanthate
• CPC Class Codes: C08J 2427/08 : Homopolymers or copolymers of vinylidene chloride
• CPC Class Codes: C08J 5/18 : Manufacture of films or sheets
• CPC Class Codes: C08J 7/0427 : with only one layer of a composition containing a polymer binder with more layers C08J7/042
• CPC Class Codes: C08J 7/048 : Forming gas barrier coatings

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).

Claims

1. A method of manufacturing a detectable cellulosic food packaging film, which cellulosic film comprises detectable particles incorporated therein, wherein the method comprises 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 disversant, wherein the detectable particles are magnetic and are detectable by a metal detection device and wherein the dispersant is selected among surface-active detergents and polymers,

(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 a detectable cellulosic food packaging film comprising the detectable particles incorporated therein in homogeneous distribution.

49. The method as defined in claim 1,

wherein the dispersant is a surface-active polymer having a number-average molecular weight of at least 500 g/mol and up to 1,000,000 g/mol;

and

wherein the dispersant is a surface-active polymer comprising functional groups.

50. The method as defined in claim 1,

wherein the dispersant is a polymeric dispersant based on a naphthalene condensate or its neutral salts.

51. The method as defined in claim 1,

wherein the dispersant is used in amounts, calculated as the weight ratio of detectable particles:

dispersant, in the range of from 2,000;

1 to 1;

1.

52. The method as defined in claim 1,

wherein the detectable particles are introduced into the solution or dispersion comprising at least one of a cellulose and a cellulose precursor or derivative in the presence of at least one rheology modifier.

53. The method as defined in claim 52,

wherein the rheology modifier is a thickening agent comprising a cellulose derivative selected among cellulose esters and cellulose ethers.

54. The method as defined in claim 1,

wherein the detectable particles are introduced in the form of a dispersion wherein the dispersion comprises the detectable particles in amounts of from 0.5 to 80 wt. % based on the dispersion.

55. The method as defined in claim 54,

wherein the dispersion further comprises the at least one dispersant.

56. The method as defined in claim 1,

wherein the detectable particles comprise or consist of at least one magnetic metal or metal oxide selected among iron (Fe), cobalt (Co) nickel (Ni) and their oxides.

57. The method as defined in claim 1,

wherein the detectable particles comprise or consist of at least one magnetic iron oxide.

58. The method as defined in claim 1,

wherein the detectable particles comprise or consist of 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.

59. The method as defined in claim 1,

wherein the detectable particles comprise iron (Fe) in weight-related amounts in the range of from 20 to 80 wt. %, based on the overall particle weight.

60. The method as defined in claim 1,

wherein the detectable particles comprise a weight-related specific saturation magnetization of at least 50 Am²/kg iron (Fe).

61. The method as defined in claim 1,

wherein the detectable particles comprise absolute particle sizes in the range of from 0.01 to 1,000 micrometers.

62. The method as defined in claim 1,

wherein the detectable particles are used in such amounts that the resulting cellulosic film comprising the detectable particles incorporated therein comprises 0.1 to 50 wt. % of the detectable particles, based on the overall weight of the cellulosic film comprising the detectable particles incorporated therein.

63. The method as defined in claim 1,

wherein the cellulosic film comprising the detectable particles incorporated therein comprises 0.1 to 20 wt. % of the detectable particles, based on the overall cellulosic film weight.

64. The method as defined in claim 1,

wherein the regeneration and recovery of the cellulose is combined with an extrusion step.

65. The method as defined in claim 1,

wherein the slurry resulting from introducing the detectable particles into the solution or dispersion comprising at least one of a cellulose and a cellulose precursor or derivative is subjected to an extrusion process during or combined with the regeneration and recovery of the cellulose, wherein the slurry is extruded into at least one regeneration bath comprising a chemical required to regenerate and recover the cellulose, comprising precipitating the cellulose or to convert and react the cellulose precursor or derivative to cellulose, so as to obtain an extrudate comprising one of a regenerated cellulose and cellulose hydrate (cellophane).

2-48. -48. (canceled)

66. A detectable cellulosic food packaging film, which detectable cellulosic food packaging film is made of at least one of a regenerated cellulose and cellulose hydrate (cellophane) comprising detectable particles incorporated therein.

67. The film as defined in claim 66,

wherein the detectable particles are incorporated in homogeneous distribution.

68. The film as defined in claim 66,

wherein the detectable particles comprise or consist of at least one magnetic metal or metal oxide selected among iron (Fe), cobalt (Co) nickel (Ni) and their oxides.

69. The film as defined in claim 66,

wherein the detectable particles comprise or consist of at least one magnetic iron oxide.

70. The film as defined in claim 66,

wherein the detectable particles comprise or consist of 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.

71. The film as defined in claim 66,

wherein the detectable particles comprise iron (Fe) in weight-related amounts in the range of from 20 to 80 wt. %, based on the overall particle weight.

72. The film as defined in claim 66,

wherein the detectable particles comprise a weight-related specific saturation magnetization of at least 50 Am²/kg iron (Fe).

73. The film as defined in claim 66,

wherein the detectable particles comprise absolute particle sizes in the range of from 0.01 to 1,000 micrometers.

74. The film as defined in claim 66,

which the detectable cellulosic food packaging film comprises the detectable particles in amounts of from 0.1 to 50 wt. %, based on the overall weight of the cellulosic film comprising the detectable particles incorporated therein.

75. The film as defined in claim 66,

which the detectable cellulosic food packaging film comprises the detectable particles in amounts of from 0.1 to 20 wt. % of the detectable particles, based on the overall cellulosic film weight.

76. The film as defined in claim 66,

wherein the detectable cellulosic food packaging film is in the form of a flat film, a sheet, a tubular film, a casing or a bag.

77. The film as defined in claim 66,

wherein the detectable cellulosic food packaging film is flat or tubular.

78. The film as defined in claim 66,

wherein the detectable cellulosic food packaging film forms a seamless tube.

79. The film as defined in claim 66,

wherein the detectable cellulosic food packaging film forms a seamless tubular casing.

80. The film as defined in claim 66,

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, wherein the detectable particles are magnetic and are detectable by a metal detection device and wherein the dispersant is selected among surface-active detergents and polymers,

(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 a detectable cellulosic food packaging film comprising the detectable particles incorporated therein in homogeneous distribution.

81. A foodstuff article packaged in a detectable cellulosic food packaging film as defined in claim 66.