METHOD OF FORMING A REINFORCED PARCHMENTED NONWOVEN PRODUCT, AND THE PRODUCT

• US 20100139877A1
• Filed: 01/10/2008
• Published: 06/10/2010
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Ahlstrom Corporation
• Original Assignee: Ahlstrom Corporation
• Inventors: Bras, Julien, Black, Michael Dennis, Cartier, Noël, Volpe, Raymond, Wightman, Alan, Vaca-Garcia, Carlos
• Granted Patent: US 8,317,977 B2
• Time in Patent Office: Days
• US Class Current: 162/146
• CPC Class Codes: A22C 13/0003 Apparatus for making sausage casings, e.g. simultaneously with stuffing artificial casings enclosing material webs being formed into tubes in situ around filling nozzles B65B9/20
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: D04H 1/4374 using different kinds of webs, e.g. by layering webs
• CPC Class Codes: D04H 1/54 by welding together the fibres, e.g. by partially melting or dissolving in combination with needling D04H1/485
• CPC Class Codes: D04H 1/587 characterised by the bonding agents used
• CPC Class Codes: D04H 5/03 by fluid jet
• CPC Class Codes: D06M 11/55 with sulfur trioxide; with sulfuric acid or thiosulfuric acid or their salts
• CPC Class Codes: D06M 11/64 with nitrogen oxides; with oxyacids of nitrogen or their salts with pernitric acids or their salts D06M11/50
• CPC Class Codes: D06M 11/70 with oxides of phosphorus; with hypophosphorous, phosphorous or phosphoric acids or their salts
• CPC Class Codes: D06M 13/188 Monocarboxylic acids; Anhydrides, halides or salts thereof D06M13/1845 takes precedence
• CPC Class Codes: D06M 15/05 Cellulose or derivatives thereof
• CPC Class Codes: D21H 27/06 Vegetable or imitation parchment; Glassine paper

Abstract

This specification is generally related to reinforced, parchmented paper, composite, reinforced parchmented paper and methods of manufacture thereof. The reinforced, parchmented paper may be used to form a sausage casing.

Claims

1-60. -60. (canceled)

61. A method of forming a layered precipitated nonwoven product comprising:

a) Forming a nonwoven base sheet of at least non-cellulose fibers,

b) Applying on the base sheet material sensitive to a gelatinizing agent,

c) Associating said base sheet and said material together to form a composite sheet,

d) Treating one of

the base sheet before or during step c),

the material sensitive to a gelatinizing agent before or during step c) and

the composite sheet during or after step c)

 

with a gelatinizing agent to partially dissolve some material sensitive to gelatinizing agent,

e) Washing the gelatinized sheet to remove gelatinizing agent and to regenerate and to precipitate the material dissolved/gelatinized in step d), and

f) Drying the product.

62. The method of claim 61, characterized in, in step a) depositing thermoplastic filaments on a moving forming surface to form a spunlaid batt of filaments, and bonding the thus deposited filaments by thermal point bonding or by through air bonding to form the base sheet.

63. The method of claim 61, characterized in that the material sensitive to a gelatinizing agent is a fibrous material.

64. The method of claim 63, characterized in that the fibrous material sensitive to a gelatinizing agent is one or more of cellulose, chitosan, rayon, nylon, polylactic acid (PLA), and the gelatinizing agent is one or more of aqueous solutions of alkalis, such as caustic soda;

acids such as sulfuric, phosphoric, nitric, formic or acetic acid;

acid salts of zinc, tin, antimony or aluminum, like zinc chloride, and PLA solvent, respectively.

65. The method of claim 61, characterized in that the material sensitive to a gelatinizing agent is a non-fibrous film, preferably a cellulose film or a nylon film, more preferably a cellophane film.

66. The method of claim 61, characterized in using the dissolved material for bonding at least some of the fibers of the base sheet.

67. The method of claim 61, characterized in that the nonwoven base sheet formed in step a) comprises, in addition to non-cellulose fibers, also material sensitive to a gelatinizing agent, like for instance cellulose fibers, nylon, or cellophane.

68. The method of claim 61, characterized in deriving the non-cellulose fibers from at least one of glass, carbon, polyethylene terephthalate (PET), a mixture of polyethylene terephthalate polymers with similar or modified chemistries (for example CHDM (1,4-cyclohexanedimethanol) modified polyethylene terephthalate), polylactic acid (PLA), other polyesters such as polybutylene terephthalate (PBT) and poly trimethylene terephthalate (PTT), polypropylene (PP), polyethylene (PE), polyamide, copolymers of any of these polymers, mixtures of any of these polymers, and chitosan.

69. The method of claim 61, characterized in forming the base sheet of continuous or staple length thermoplastic fibers and cellulose fibers.

70. The method of claim 61, characterized in, in step b), for forming a nonwoven composite product, applying material sensitive to a gelatinizing agent, preferably fibrous material, more preferably cellulose fibers, on the base sheet as a pre-formed web or tissue or sheet or by means of a wet-laying or an air-laying process.

71. The method of claim 63, characterized in, in step c), for forming a nonwoven composite sheet, associating said fibrous material sensitive to a gelatinizing agent with the base sheet by wet pressing or by entangling.

72. The method of claim 61, characterized in overlaying additional sheets to the composite sheet to form a more layered composite precipitated product.

73. The method of claim 61, characterized in forming at least one of the sheets at least partially of filaments extending substantially continuously in the machine direction.

74. The method of claim 61, characterized in positioning the sheets one over the other either before, during or after the treatment with a gelatinizing agent.

75. The method of claim 61, characterized in, for forming a layered precipitated product, associating the sheets to each other by the gelatinized and precipitated material.

76. The method of claim 61, characterized in treating the base sheet or base sheet composite with a plasticizing agent.

77. The method of claim 61, characterized in cutting the reinforced gelatinized/precipitated nonwoven product into strips, folding the strips to form tubes, and fastening the sides of the strips to form a seam.

79. A layered precipitated nonwoven product produced in accordance with the method of claim 61, characterized in that the product is formed of at least a nonwoven web of thermoplastic fibers, and a layer of material sensitive to a gelatinizing agent associated with the thermoplastic nonwoven web, the material sensitive to a gelatinizing agent being precipitated at least partially.

80. The layered precipitated nonwoven product of claim 79, characterized in that the product is formed of

a first nonwoven layer comprising precipitated material sensitive to a gelatinizing agent having an outer face and an inner face,

a second nonwoven layer of substantially continuous thermoplastic filaments and fibrous material sensitive to a gelatinizing agent entangled with the thermoplastic filaments, the second layer having an inner face adjacent the first layer, filaments from the inner face being at least partially embedded in precipitated material sensitive to a gelatinizing agent, and

the first and second layers being bonded together by precipitated material sensitive to a gelatinizing agent derived from the fibrous material sensitive to a gelatinizing agent, the material sensitive to a gelatinizing agent or both.

81. The layered precipitated nonwoven product of claim 79, and suitable for the preparation of a casing material for the packaging of a food product, characterized in a plurality of randomly oriented, thermoplastic fibers and fibrous material sensitive to a gelatinizing agent entangled with the thermoplastic fibers, some portion of the fibrous material sensitive to a gelatinizing agent being precipitated.

82. A layered precipitated nonwoven product produced in accordance with the method of claim 61, and suitable for the preparation of a casing material for the packaging of a food product, characterized in

a first nonwoven layer of substantially continuous filaments, the first layer having an inner face,

a second nonwoven layer comprising precipitated material sensitive to a gelatinizing agent having an exterior face and an opposing inner face;

some filaments being embedded within precipitated material sensitive to a gelatinizing agent adjacent the second layer inner face; and

the layers being bonded together only by precipitated material sensitive to a gelatinizing agent.

83. The layered precipitated nonwoven product of claim 82, characterized in that the material sensitive to a gelatinizing agent of the second layer comprises one or more of cellulose fibers, and a cellulose film.

84. The layered precipitated nonwoven product of claim 83, characterized in that cellulose fibers are entangled with the filaments of the first nonwoven layer

85. The layered precipitated nonwoven product of claim 82, characterized in the exterior surface at least partially comprising a thin dense layer of precipitated material.

86. The layered precipitated nonwoven product of claim 82, characterized in cellulose fibers interposed between filaments of the first layer, and that the precipitated material is precipitated cellulose.

78. A method of forming a layered precipitated tubular nonwoven product comprising:

a) Forming a nonwoven base sheet of at least non-cellulose fibers,

b) Applying on the base sheet material sensitive to a gelatinizing agent,

c) Associating said base sheet and said material together to form a composite sheet,

d) Forming the composite sheet into a tube,

e) Joining the edges thereof,

f) Treating the composite sheet before steps d) and e) or the tube after step e) with a gelatinizing agent to partially dissolve some material sensitive to gelatinizing agent,

g) Washing the tube to remove gelatinizing agent and to regenerate and to precipitate the material dissolved/gelatinized in step f), and

h) Drying the product.