U.S. patent application number 09/896552 was filed with the patent office on 2002-08-22 for grease masking packaging materials and methods thereof.
Invention is credited to Gould, Richard J..
Application Number | 20020114933 09/896552 |
Document ID | / |
Family ID | 27401163 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020114933 |
Kind Code |
A1 |
Gould, Richard J. |
August 22, 2002 |
Grease masking packaging materials and methods thereof
Abstract
The present invention relates generally to the packaging
materials. More specifically, the invention relates to materials
and methods suitable for use as packaging materials whereby the
appearance of grease, fat or oil staining on the packaging material
is reduced or eliminated.
Inventors: |
Gould, Richard J.; (St.
Paul, MN) |
Correspondence
Address: |
NEEDLE & ROSENBERG, P.C.
The Candler Building, Suite 1200
127 Peachtree Street, N.E.
Atlanta
GA
30303-1811
US
|
Family ID: |
27401163 |
Appl. No.: |
09/896552 |
Filed: |
June 29, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60258686 |
Dec 28, 2000 |
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60298868 |
Jun 15, 2001 |
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Current U.S.
Class: |
428/212 ;
428/59 |
Current CPC
Class: |
B65D 81/264 20130101;
Y10T 428/193 20150115; B32B 2553/00 20130101; B65D 65/16 20130101;
D21H 19/82 20130101; B32B 2307/402 20130101; B32B 29/00 20130101;
B32B 27/20 20130101; Y10T 428/24942 20150115; D21H 27/10
20130101 |
Class at
Publication: |
428/212 ;
428/59 |
International
Class: |
B32B 003/00; B32B
007/02 |
Claims
What is claimed is:
1. A material for packaging grease, fat or oil-containing
substances, wherein the material comprises: a. a grease, fat or oil
permeable substrate suitable for use as a packaging material,
wherein the substrate has an inner and an outer surface; b. a dark
colored layer comprising a dark colorant and having an inner and an
outer surface, wherein the dark colored layer is optionally applied
from a solution comprising a dark colorant, and wherein the inner
surface of the dark colored layer is disposed proximal to the outer
surface of the substrate; and c. a light colored layer having an
inner and an outer surface, wherein the light colored layer is
applied from a solution comprising a light colorant, and wherein
the inner surface of the light colored layer is disposed proximal
to the outer surface of the dark colored layer; wherein one or more
of the light colored or dark colorant-containing solutions each,
independently, comprises a binder material at from about 17% to
about 60% by weight of the respective colorant-containing solution,
wherein the dark and light colored layers are selected to mask an
appearance of grease, fat or oil staining on the packaging
material, and wherein neither the dark colored layer nor the light
colored layer comprises a non-leafing metallic ink.
2. The packaging material of claim 1, wherein the inner surface of
the light colored layer is adjacent to the outer surface of the
dark colored layer.
3. The packaging material of claim 1, wherein the inner surface of
the dark colored layer is adjacent to the outer surface of the
substrate.
4. The packaging material of claim 1, wherein the dark colorant
comprises one or more of: carbon black, raw sienna, burnt sienna,
burnt umber, chrome black, high purity furnace black, black azo
dyes or brown azo dyes.
5. The packaging material of claim 1, wherein the dark colorant
comprises carbon black.
6. The packaging material of claim 1, wherein the light colorant
comprises one or more of: titanium dioxide, calcium carbonate,
calcium silicate, calcium sulfate, barium sulfate, natural clay,
synthetic clay, magnesium oxide, magnesium silicate, zinc
carbonate, zinc oxide or plastic pigment.
7. The packaging material of claim 1, wherein the light colorant
comprises titanium dioxide.
8. The packaging material of claim 1, wherein the dark colored
layer is applied from the dark colorant-containing solution and the
solution comprises from about 0.01 to about 20.0% by weight of the
dark colorant as measured by total weight of the solution.
9. The packaging material of claim 1, wherein the dark colored
layer is applied from the dark colorant-containing solution and the
solution comprises from about 0.25 to about 4.0% by weight of the
dark colorant as measured by total weight of the solution.
10. The packaging material of claim 1, wherein the light
colorant-containing solution comprises from about 30 to about 90%
by weight of the light colorant as measured by total weight of the
solution.
11. The packaging material of claim 1, wherein the light
colorant-containing solution comprises from about 40 to about 80%
by weight of the light colorant as measured by total weight of the
solution.
12. The packaging material of claim 1, wherein the substrate
comprises one or more dark colored outer plys, thereby providing
the dark colored layer on the outer surface of the substrate.
13. The packaging material of claim 1 having a TAPPI brightness
number of from about 60 to about 90.
14. The packaging material of claim 1, wherein the dark colored
layer is applied from the dark colorant-containing solution and the
solution further comprises a sizing agent, dark colored pigment and
water.
15. The packaging material of claim 14, wherein the sizing agent
comprises starch.
16. The packaging material of claim 1, wherein the grease, fat or
oil permeable substrate comprises paperboard, paper or fabric.
17. The packaging material of claim 1, wherein the grease, fat or
oil permeable substrate comprises paperboard.
18. The packaging material of claim 17, wherein the paperboard
comprises one or more of: SBS, SUS or recycled paperboard.
19. The packaging material of claim 1, wherein the packaging
material is suitable for use in packaging of human food, animal
food, drugs or cosmetics.
20. The packaging material of claim 1, wherein one or more of the
dark or the light colorant-containing solutions each,
independently, further comprise one or more of: water, dispersant,
resin, surfactant, wetting agent, defoamer, thickener, starch,
preservative or antioxidant.
21. The packaging material of claim 1, wherein the binder is
present at from about 20 to about 50% by weight of the light or
dark colorant-containing solutions.
22. The packaging material of claim 1, wherein the binder comprises
one or more of a naturally or synthetically derived binder.
23. The packaging material of claim 1, wherein the binder comprises
a latex polymer and a protein.
24. The packaging material of claim 23, wherein the ratio of latex
polymer to protein is from about 2:1 to about 10:1.
25. The packaging material of claim 1, further comprising a printed
layer adjacent to the outer surface of the light colored layer.
26. An article prepared from the packaging material of claim 1.
27. The article of claim 26, wherein the article further comprises
a consumer good.
28. The article of claim 26 in the form of a wrap, pouch, bag, box,
cup, tray, plate, can, tube or bottle.
29. The article of claim 26, further comprising a food material
comprising one or more of: sweets, chocolate, confectionery,
pastries, biscuits, dairy products, powdery foodstuffs, frozen
food, fresh and semipreserved foods, pet food, or carryout
foods.
30. The article of claim 26, further comprising a non-food material
comprising one or more of: cosmetics, toiletries, pharmaceuticals,
cigarettes, detergents, textiles, toys, games, tools, household
appliances, pesticides, fertilizers, hobby items, paper products,
cassettes, record sleeves, or auto parts.
31. A material for packaging grease, fat or oil-containing
substances, wherein the material comprises: a. a grease, fat or oil
permeable substrate suitable for use as a packaging material,
wherein the substrate has an inner and an outer surface; b. a dark
colored layer comprising a dark colorant and having an inner and an
outer surface, wherein the dark colored layer is optionally applied
from a composition comprising a dark colorant, and wherein the
inner surface of the dark colored layer is disposed proximal to the
outer surface of the substrate; and c. a light colored layer having
an inner and an outer surface, wherein the light colored layer is
applied from a composition comprising a light colorant and one or
more of: polyethylene, polypropylene, polyester, polystyrene, or
halogenated or non-halogenated vinyl polymer, and wherein the inner
surface of the light colored layer is disposed proximal to the
outer surface of the dark colored layer; wherein the dark and light
colored layers are selected to mask an appearance of grease, fat or
oil staining on the packaging material, and wherein neither the
dark colored layer nor the light colored layer comprises a
non-leafing metallic ink.
32. The packaging material of claim 31, wherein the dark colored
layer is applied from the dark colorant-containing composition and
the dark and light colored compositions each, independently,
comprise from about 5 to about 40% colorant as measured by the
total weight of each colored composition.
33. The packaging material of claim 31, wherein the dark colored
layer is applied from the dark colorant-containing composition and
the composition comprises one or more of: polyethylene,
polypropylene, polyester, polystyrene, or halogenated or
non-halogenated vinyl polymer.
34. An article prepared from the packaging material of claim
31.
35. The article of claim 34 in the form of a wrap, pouch, bag, box,
cup, tray, plate, can, tube or bottle.
36. The article of claim 34 further comprising a consumer good.
37. The article of claim 34 further comprising a food material
comprising one or more of: sweets, chocolate, confectionery,
pastries, biscuits, dairy products, powdery foodstuffs, frozen
food, fresh and semipreserved foods, pet food, or carryout
foods.
38. The article of claim 34 further comprising a non-food material
comprising one or more of: cosmetics, toiletries, pharmaceuticals,
cigarettes, detergents, textiles, toys, games, tools, household
appliances, pesticides, fertilizers, hobby items, paper products,
cassettes, record sleeves, or auto parts.
39. A material for packaging grease, fat or oil-containing
substances, wherein the material comprises: a. a grease, fat or oil
permeable substrate suitable for use as a packaging material,
wherein the substrate has an inner and an outer surface; b. a dark
colored layer comprising a dark colorant and having an inner and an
outer surface, wherein the dark colored layer is optionally applied
from a solution comprising a dark colorant, and wherein the inner
surface of the dark colored layer is disposed proximal to the outer
surface of the substrate; and c. a light colored layer having an
inner and an outer surface, wherein the light colored layer is
applied from a solution comprising a light colorant, and wherein
the inner surface of the light colored layer is disposed proximal
to the outer surface of the dark colored layer; wherein one or more
of the light colored or dark colorant-containing solutions each,
independently, comprises a binder material at from about 17% to
about 60% by weight of the respective colorant containing solution,
wherein the dark and light colored layers are selected to mask an
appearance of grease, fat or oil staining on the packaging
material, and wherein both the dark colorant and light colorant
containing solutions are aqueous.
40. The packaging material of claim 39, wherein neither the dark
colored layer nor the light colored layer comprises a non-leafing
metallic ink.
41. The packaging material of claim 39, wherein the dark colored
layer is applied from the dark colorant-containing solution and the
solution comprises a sizing agent, dark colored pigment and
water.
42. The packaging material of claim 39, wherein the sizing agent
comprises starch.
43. The packaging material of claim 39, wherein the grease, fat or
oil permeable substrate comprises paperboard, paper or fabric.
44. The packaging material of claim 43, wherein the substrate
comprises paperboard comprising one or more of: SBS, SUS or
recycled paperboard.
45. The packaging material of claim 39, wherein the packaging
material is suitable for use in packaging human food, animal food,
drugs or cosmetics.
46. The packaging material of claim 39, wherein the binder
comprises one or more of: a naturally or a synthetically derived
binder.
47. The packaging material of claim 39, wherein the binder
comprises a latex polymer and a protein.
48. The packaging material of claim 47, wherein the ratio of latex
polymer to protein is from about 2:1 to about 10:1.
49. An article prepared from the packaging material of claim
39.
50. The article of claim 49, in the form of a wrap, pouch, bag,
box, cup, tray, plate, can, tube or bottle.
51. The article of claim 49 further comprising a consumer good.
52. The article of claim 49 further comprising a food material
comprising one or more of: sweets, chocolate, confectionery,
pastries, biscuits, dairy products, powdery foodstuffs, frozen
food, fresh and semipreserved foods, pet food, or carryout
foods.
53. The article of claim 49 further comprising a non-food material
comprising one or more of: cosmetics, toiletries, pharmaceuticals,
cigarettes, detergents, textiles, toys, games, tools, household
appliances, pesticides, fertilizers, hobby items, paper products,
cassettes, record sleeves, or auto parts.
54. A method of making a packaging material that masks grease, fat
or oil permeation in a grease, fat or oil permeable packaging
material comprising the steps of: a. providing a grease, fat or oil
permeable substrate suitable for use as a packaging material,
wherein the substrate has an inner and an outer surface; b.
selecting a dark colored layer having an inner and an outer surface
and a light colored layer having an inner and an outer surface,
wherein the layers are together suitable for masking an appearance
of a grease, fat or oil permeation on the packaging material; c.
applying the dark colored layer proximal to the outer surface of
the substrate, wherein the dark colored layer is optionally applied
from a solution comprising a dark colorant; and d. applying the
light colored layer proximal to the outer surface of the dark
colored layer, wherein the light colored layer is applied from a
solution comprising a light colorant; wherein one or more of the
dark or light colorant-containing solutions each, independently,
comprises a binder material at from about 17% to about 60% by
weight as measured by weight of the respective solution, and
wherein neither the dark colored layer nor the light colored layer
comprises a non-leafing metallic ink.
55. The method of claim 54, wherein the inner surface of the dark
colored layer is adjacent to the outer surface of the
substrate.
56. The method of claim 54, wherein the inner surface of the light
colored layer is adjacent to the outer surface of the dark colored
layer.
57. The method of claim 54, wherein the dark colorant comprises one
or more of: carbon black, raw sienna, burnt sienna, burnt umber,
chrome black, high purity furnace black, black azo dyes or brown
azo dyes.
58. The method of claim 54, wherein the dark colorant comprises
carbon black.
59. The method of claim 54, wherein the light colorant comprises
one or more of: titanium dioxide, calcium carbonate, calcium
silicate, calcium sulfate, barium sulfate, natural clay, synthetic
clay, magnesium oxide, magnesium silicate, zinc carbonate, zinc
oxide or plastic pigment.
60. The method of claim 54, wherein the light colorant comprises
titanium dioxide.
61. The method of claim 54, wherein the dark colored layer is
applied from the dark colorant-containing solution and the solution
comprises from about 0.01 to about 20.0% by weight of the dark
colorant as measured by total weight of the solution.
62. The method of claim 54, wherein the dark colored layer is
applied from the dark colorant-containing solution and the solution
comprises from about 0.25 to about 4.0% by weight of the dark
colorant as measured by total weight of the solution.
63. The method of claim 54, wherein the light colorant-containing
solution comprises from about 30 to about 90% by weight of the
light colorant as measured by total weight of the solution.
64. The method of claim 54, wherein the light colorant-containing
solution comprises from about 40 to about 80% by weight of the
light colorant as measured by total weight of the solution.
65. The method of claim 54 having a TAPPI brightness number of from
about 60 to about 90.
66. The method of claim 54, wherein the dark colored layer is
applied from the dark colorant-containing solution and the solution
further comprises a sizing agent, dark colored pigment and
water.
67. The method of claim 66, wherein the sizing agent comprises
starch.
68. The method of claim 54, wherein the grease, fat or oil
permeable substrate comprises paperboard, paper or fabric.
69. The method of claim 54, wherein the grease, fat or oil
permeable substrate comprises paperboard.
70. The method of claim 69, wherein the paperboard comprises one or
more of: SBS, SUS or recycled paperboard.
71. The method of claim 54, wherein the packaging material is
suitable for use in packaging human food, animal food, drugs or
cosmetics.
72. The method of claim 54 further comprising the step of forming
the packaging material into a wrap, pouch, bag, box, cup, tray,
plate, can, tube or bottle, thereby forming an article.
73. The method of claim 72, further comprising the step of
including a packaged material in the article, wherein the packaged
material comprises one or more of: sweets, chocolate,
confectionery, pastries, biscuits, dairy products, powdery
foodstuffs, frozen food, fresh and semipreserved foods, pet food,
carryout foods, cosmetics, toiletries, pharmaceuticals, cigarettes,
detergents, textiles, toys, games, tools, household appliances,
pesticides, fertilizer, hobby items, paper products, cassettes,
record sleeves, or auto parts.
74. The method of claim 54, wherein one or more of the dark colored
layer and the light colored layers each, independently, comprises
one or more of: water, dispersant, resin, surfactant, wetting
agent, defoamer, thickener, starch, preservative or
antioxidant.
75. The method of claim 54, wherein the binder comprises one or
more of: a naturally or synthetically derived binder.
76. The method of claim 54, wherein the binder comprises a latex
polymer and a protein.
77. The method of claim 76, wherein the ratio of latex polymer to
protein is from about 2:1 to about 10:1.
78. The method of claim 54, further comprising applying a printed
layer adjacent to the outer surface of the light colored layer.
79. A method for masking grease, fat or oil staining on a packaging
material, wherein the method comprises the steps of: (a) contacting
the packaging material of claim 54 with a grease, fat or oil
containing material.
80. A method of making a packaging material that masks grease and
oil permeation in a grease, fat or oil packaging material,
comprising the steps of: a. providing a grease, fat or oil
permeable substrate having an inner and an outer surface, wherein
the substrate is suitable for use as a packaging material; b.
selecting a dark colored layer having an inner and an outer surface
and a light colored layer having an inner and an outer surface,
wherein the layers are together suitable for masking an appearance
of grease, fat or oil permeation on the packaging material; c.
extruding a composition comprising a dark colorant proximal to the
outer surface of the substrate, thereby providing the dark colored
layer; and d. extruding, either simultaneously or sequentially to
step (c), a composition comprising a light colorant proximal to the
outer surface of the dark colored layer, thereby providing the
light colored layer.
81. The method of claim 80, wherein the dark colored layer and
light colored layer each, independently, comprises one or more of:
polyethylene, polypropylene, polyester, polystyrene or halogenated
or non-halogenated vinyl polymer.
82. The method of claim 80, wherein the dark colored layer and the
light colored layer each, independently, comprise from about 5 to
about 40% colorant as measured by total weight of each individual
layer.
83. The method of claim 80, wherein the light colored layer
comprises one or more of: titanium dioxide, calcium carbonate,
calcium silicate, calcium sulfate, barium sulfate, natural clay, a
synthetic clay, magnesium oxide, magnesium silicate, zinc carbonate
or zinc oxide.
84. The method of claim 80, wherein the light colored layer
comprises titanium dioxide.
85. The method of claim 80, wherein the substrate comprises
paperboard comprising one or more of: SBS, SUS or recycled
paperboard.
86. The method of claim 80, wherein the packaging material is
suitable for use in packaging human food, animal food, drugs and
cosmetics.
87. The method of claim 80 further comprising forming the packaging
material into a wrap, pouch, bag, box, cup, tray, plate, can, tube
or bottle, thereby forming an article.
88. The method of claim 87 further comprising including a packaged
material in the article comprising one or more of: sweets,
chocolate, confectionery, pastries, biscuits, dairy products,
powdery foodstuffs, frozen food, fresh and semipreserved foods, pet
food, carryout foods, cosmetics, toiletries, pharmaceuticals,
cigarettes, detergents, textiles, toys, games, tools, pesticides,
fertilizers, household appliances, hobby items, paper products,
cassettes, record sleeves, or auto parts.
89. A method for masking the appearance of grease, fat or oil
staining on a packaging material, wherein the method comprises: (a)
contacting the packaging material of claim 80, with a grease, fat
or oil containing material.
90. A method for making a packaging material that masks grease, fat
or oil permeation in a grease, fat or oil permeable packaging
material, comprising the steps of: a. providing a grease, fat or
oil permeable substrate having an outer surface and a dark colored
outer layer having an inner and an outer surface, wherein the
substrate is suitable for use as a packaging material; and b.
extruding a composition comprising a light colorant proximal to the
outer surface of the dark colored outer layer, thereby providing a
light colored outer layer, wherein the dark colored layer and the
light colored outer layer are selected so as to mask the appearance
of grease, fat or oil staining on the packaging material, thereby
providing a packaging material suitable for masking the appearance
of grease, fat or oil on the material.
91. The method of claim 90, wherein the dark colored outer layer is
obtained by extruding a composition comprising a dark colorant
proximal to the outer surface of the substrate prior to the
extrusion step.
92. The method of claim 90, wherein the dark colored outer layer is
obtained by applying a solution comprising a dark colorant to the
outer surface of the substrate prior to the extrusion step.
93. The method of claim 90, wherein the dark colored outer surface
is obtained by placing a dark colored paper or fabric layer on the
outer surface of the substrate prior to the extrusion step.
94. The method of claim 90, wherein the dark colored outer surface
is obtained by including one or more dark colored plys in the outer
surface of the substrate prior to the extrusion step.
95. A method for masking grease, fat or oil staining on a packaging
material method, wherein the method comprises: a. contacting the
packaging material of claim 90 with a grease, fat or oil containing
material.
96. A method for making a material for masking grease and oil
permeation in a grease, fat or oil permeable, substrate, comprising
the steps of: a. providing a grease, fat or oil permeable substrate
having an inner and an outer surface, wherein the substrate is
suitable for use as a packaging material; b. selecting a dark
colored layer and a light colored layer wherein the layers are
together suitable for masking grease, fat or oil permeation in the
substrate; c. extruding either simultaneously or sequentially a
composition comprising a dark colorant and a composition comprising
a light colorant, thereby forming a laminate material having an
inner and an outer surface, wherein the light colored layer forms
the outer surface of the laminate material and the dark colored
layer forms the inner surface of the laminate material; d. applying
the inner surface of the laminate material to the outer surface of
the substrate, thereby providing a packaging material suitable for
masking the appearance of grease, fat or oil on the material.
97. A method for masking grease, fat or oil staining on a packaging
material, wherein the method comprises: a. contacting the packaging
material of claim 96, with a grease, fat or oil containing
material.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application No. 60/298,868, filed Jun. 15, 2001. This application
also claims priority to U.S. Provisional Application No.
60/258,686, filed Dec. 28, 2000. The disclosures of each of these
applications are incorporated herein by reference in their
entireties.
FIELD OF THE INVENTION
[0002] The present invention relates generally to packaging
materials. More specifically, the invention relates to materials
suitable for use as packaging materials, whereby the appearance of
grease, fat or oil staining on the packaging material is reduced or
eliminated.
BACKGROUND OF THE INVENTION
[0003] Packaging materials, such as paperboard, paper or fabric are
frequently utilized to package grease, fat or oil-containing
materials. For example, human and animal foodstuffs commonly
include a significant amount of grease, fat or oil. During filling,
transport or storage, the grease, fat or oil from the foodstuff can
migrate from the food product to the packaging material, thereby
resulting in unsightly stains on the outer surface of the packaging
material. Also, grease, fat or oil-containing materials may come
into contact with the outer surface of the packaging material to
cause staining. While this migration of grease, fat or oil does not
normally effect the structural integrity of the packaging material,
the consumer generally dislikes the stained container and may be
less likely to purchase a product because of such staining.
[0004] One solution to the problem of grease, fat or oil staining
on a packaging material is to place the material to be packaged
within an separate impermeable container within the packaging
material itself such as, for example, a plastic bag. While such a
method normally prevents grease, fat or oil staining in the
packaging material prior to use by the consumer of the packaged
material, this method has less effectiveness when the package has
been opened and returned to the consumer's shelf for storage. For
example, grease, fat or oil-containing crackers may be placed in a
plastic bag within a packaging material. Grease, fat or oil will be
contained within the bag as long as the bag remains closed.
However, once opened, it is quite common for a consumer to drop one
or more crackers between the bag and the inner surface of the
packaging material when removing the crackers for use. If there is
no barrier material between the outer surface of the plastic bag,
it is likely that grease, fat or oil will migrate from the cracker
into and through the packaging material, thereby resulting in an
unsightly stain on the outer surface of the packaging material.
Stains on packaging material may also be caused by filling line
debris or puncturing of the plastic bag.
[0005] Stains on the packaging material may also be caused by
contact by a grease, fat or oil-containing material with the outer
surface of the packaging material. Such stains may be from contact
of the package with a grease, fat or oil stain on another package
or by contact with grease, fat or oil-containing substances that
may occur during filling, transport or storage.
[0006] Furthermore, it will be understood that, irrespective of the
origin of a grease, fat or oil stain, extended times and elevated
temperatures will normally exacerbate the appearance of such
stains.
[0007] Whether or not a plastic bag is placed within the packaging
material, in the past, it has been common to treat the packaging
material with a barrier material effective to reduce the
possibility that grease, fat or oil will migrate into and through
the packaging material to cause a visible stain on the outer
surface of the packaging material. The most common barrier
materials from the standpoint of cost and effectiveness have been
those of the fluorochemical variety i.e., Scotchguard.RTM.
products, made by the 3M Company of Minneapolis, MN. These
materials have generally been applied to the packaging material
prior to formation into, for example, a box. However, due to
environmental and health concerns, 3M's fluorochemical barrier
products have recently been removed entirely from the market. While
other barrier materials exist, many otherwise effective methods are
either not acceptable as the sole method of protection for use in
certain applications or are applied from solvent-based systems.
Moreover, for some of the more useful methods, the methods may be
prohibitively expensive and/or not effective enough for many
applications. Thus, the removal of 3M's fluorochemical barrier
products from use has left a major void in the packaging materials
market.
[0008] U.S. Pat. No. 4,521,492 discloses a method of masking the
appearance of grease, fat or oil staining on a paperboard packaging
substrate by first applying a non-leafing metallic ink over the
substrate, followed by the application of a highly pigmented white
outer layer. It is stated that the presence of the metallic ink
alters the refractive index of the grease, fat or oil stained
substrate and the over-coating with the highly pigmented white
outer layer reduces or eliminates the metallic appearance of the
lower ink layer. While effective for the masking of grease, fat or
oil permeation, this method has at least two significant
disadvantages. First, this material requires application of at
least the non-leafing metallic ink layer using explosion-proof
equipment because the non-leafing metallic ink is delivered from a
solvent-based system. Second, the method requires the use of
solvent recovery systems. These greatly increase the cost of
utilizing this prior art grease masking system because the method
cannot be used with existing mill equipment without resulting in
difficulties. Further, the method of U.S. Pat. No. 4,521,492 has
limited applications to printing press methods which reduces the
usefulness of the process in printing processes requiring a
multiple of print stations.
[0009] Against the above, it would be highly desirable to develop a
method whereby the appearance of grease, fat or oil staining on a
packaging material could be masked so that even if grease, fat or
oil staining does occur, such stains will be less noticeable.
Specifically, it would be desirable to be able to mask the
appearance of grease, fat or oil staining on a packaging material
whereby the materials utilized do not comprise non-leafing metallic
inks. Further, it would be desirable to apply such masking methods
by way of aqueous systems, thereby allowing the use of standard
mill equipment.
SUMMARY OF THE INVENTION
[0010] In accordance with the purpose(s) of this invention, as
embodied and broadly described herein, this invention, in one
aspect, relates to a packaging material comprising a substrate
suitable for use as a packaging material wherein the appearance of
grease, fat or oil on the substrate is masked by the selection of
the color and, optionally, composition of one or more colored
layers proximally disposed on an outer surface of the substrate,
wherein the substrate may itself be colored. In a further aspect,
methods of making and using the previously described packaging
materials are provided.
[0011] Additional advantages of the invention will be set forth in
part in the description which follows, and in part will be obvious
from the description, or may be learned by practice of the
invention. The advantages of the invention will be realized and
attained by means of the elements and combinations particularly
pointed out in the appended claims. It is to be understood that
both the foregoing general description and the following detailed
description are exemplary and explanatory only and are not
restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an illustration of a coated substrate with a dark
colored layer and light colored layer disposed proximally
thereto.
[0013] FIG. 2 is an illustration of a substrate in which the outer
surface is dark colored and the substrate has a light colored layer
disposed proximally thereto.
[0014] FIG. 3 is an illustration of a substrate with a precoat
layer adjacent thereto and with a dark colored and light colored
layer disposed proximally to the precoat treated substrate.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Before the present compounds, compositions, articles,
devices, and/or methods are disclosed and described, it is to be
understood that this invention is not limited to specific methods
of making or applying the masking compositions herein, or specific
compositions thereof, and, as such, may, of course, vary. It is
also to be understood that the terminology used herein is for the
purpose of describing particular embodiments only and is not
intended to be limiting.
[0016] It must be noted that, as used in the specification and the
appended claims, the singular forms "a," "an" and "the" include
plural referents unless the context clearly dictates otherwise.
Thus, for example, reference to "a colorant" includes mixtures of
colorants.
[0017] Ranges may be expressed herein as from "about" one
particular value, and/or to "about" another particular value. When
such a range is expressed, another embodiment includes from the one
particular value and/or to the other particular value. Similarly,
when values are expressed as approximations, by use of the
antecedent "about," it will be understood that the particular value
forms another embodiment. It will be further understood that the
endpoints of each of the ranges are significant both in relation to
the other endpoint, and independently of the other endpoint.
[0018] In this specification and in the claims that follow,
reference will be made to a number of terms which shall be defined
to have the following meanings:
[0019] "Colorant" means any substance that imparts color to another
substance or mixture. As meant herein, white and black are colors.
This definition of colorant also includes, but is not limited to
pigments, dyes, whiting, barytes, clays and talc.
[0020] "Substrate color" means the color of the substrate e.g.,
paperboard, paper or fabric or other material without any added
colorant and prior to the addition of the dark colored layer or the
light colored layer. When a colorant is directly added to one or
more plys of the substrate as described hereinbelow, the substrate
color will be different from uncolored paperboard. For example,
when recycled paperboard is the substrate, the substrate color will
generally be light brown prior to the addition, if any, of colorant
to one or more plys of the paperboard.
[0021] "Light colored" as utilized to describe either a layer or a
colorant means having a value of from about 50 to about 95 on the
Cielab scale. In further separate aspects, the light colored layer
may be from about 55 to about 95 or from about 60 to about 95, or
from about 65 to about 95, or from about 75 to about 95, or from
about 80 to about 95, all such values being measured on the Cielab
scale.
[0022] "Dark colored" as utilized to describe either a layer or a
colorant means having a value of from about 0 to about 75 on the
Cielab scale. In further separate aspects, the dark colored layer
may be from about 0 to about 65, or from about 0 to about 55, or
from about 0 to about 45, or from about 0 to about 40, or from
about 0 to about 35, or from about 0 to about 30, or from about 0
to about 25, or from about 0 to about 20, or from about 0 to about
15, such values being measured on the Cielab scale.
[0023] As utilized herein, "dark colored" is defined in reference
to a corresponding "light colored layer" and vice versa. That is, a
dark colored layer (or substrate) is always darker in color that
the light colored layer that will be applied over the dark colored
layer (or substrate) when these two colored aspects combine to form
the masking aspect of the present invention. In one or more
aspects, it is possible that a dark colored layer (or substrate)
utilized with one substrate may be lighter in color than the light
colored layer utilized on a different substrate.
[0024] "Aqueous" means that the system comprises about 92% by
weight or above of water. Such systems are considered to be
essentially solvent free.
[0025] "Proximal" means that the referenced aspect or object is
near to but not necessarily touching the aspect or object to which
the word "proximal" refers. "Adjacent to" means the aspect or
object is touching the aspect or object to which the phrase
"adjacent to" refers.
[0026] References in the specification and concluding claims to
parts by weight of a particular element or component in a
composition or article, denotes the weight relationship between the
element or component and any other elements or components in the
composition or article for which a part by weight is expressed.
Thus, in a compound containing 2 parts by weight of component X and
5 parts by weight component Y, X and Y are present at a weight
ratio of 2:5, and are present in such ratio regardless of whether
additional components are contained in the compound. However,
compositions such as those disclosed and claimed herein may also be
described by one of ordinary skill in the art as containing "parts"
of a component. For example, a composition containing 100 parts
pigment and 22 parts binder would comprise 82% pigment (100/100+22)
and 18% binder (22/22+100). Such nomenclature is not used to
describe and claim the invention herein.
[0027] A weight percent of a component, unless specifically stated
to the contrary, is based on the total dry weight percent of the
formulation or composition in which the component is included.
[0028] As utilized herein, "packaging material" means a material
that may be used to make an article suitable for performing one or
more of the following functions: a) containment for handling,
transportation and use; b) preservation and protection of the
contents for required shelf and use life and sometimes protection
of the external environment from any hazards of contact with the
contents; c) identification of contents, quantity, quality and
manufacturer; and d) facilitation of dispensing and use.
Non-limiting examples of the packaging material article include a
wrap, pouch, bag, box, cup, tray, plate, can, tube, bottle or other
container form.
[0029] By the term "effective amount" of a compound or property as
provided herein it is meant such amount as is capable of performing
the function of the compound or property for which an effective
amount is expressed. As will be pointed out below, the exact amount
required will vary from process to process, depending on recognized
variables such as the compounds employed and the processing
conditions observed. Thus, it is not possible to specify an exact
"effective amount." However, an appropriate effective amount may be
determined by one of ordinary skill in the art using only routine
experimentation.
[0030] Referring first to the drawings, FIG. 1 is an illustration
of one aspect of the present invention. A substrate 12 having an
inner substrate surface 14 and an outer substrate surface 16 is
coated with a dark colored layer 18 having an inner dark colored
surface 20 and an outer dark colored surface 22 such that the dark
colored layer is disposed proximal to outer substrate surface 16. A
light colored layer 24 having an inner light colored surface 26 and
an outer light colored surface 28 is disposed proximally to outer
dark colored surface 22. A packaged good 30 may be present and may
or may not be in contact with the inner substrate surface 14.
[0031] FIG. 2 illustrates a further aspect of the present invention
wherein the substrate 32 has an integrated dark colored portion 34
having an inner dark colored surface 36 and an outer dark colored
surface 38. The light colored layer 24 may then be disposed
proximally to the outer dark colored surface 38.
[0032] FIG. 3 illustrates a further aspect of the present invention
wherein the substrate 12 has a precoat layer 40 having an inner
precoat surface 42 and an outer precoat surface 44 disposed
proximally to outer substrate surface 16 and inner dark colored
surface 20.
[0033] Now referring to a first major aspect of the present
invention, the invention provides a material for packaging grease,
fat or oil-containing substances, wherein the packaging material
comprises: a grease, fat or oil permeable substrate suitable for
use as a packaging material, wherein the substrate has an inner and
an outer surface; a dark colored layer having an inner and outer
surface disposed proximal to the outer surface of the substrate,
wherein the dark colored layer comprises a dark colorant; and a
light colored layer having an inner and an outer surface disposed
proximal to an outer surface of the dark colored layer, wherein the
light colored layer comprises a light colorant; wherein the dark
and light colored layers are selected to mask the appearance of
grease, fat or oil staining on the packaging material, and wherein
neither the dark colored layer nor the light colored layer
comprises a non-leafing metallic ink. By "non-leafing metallic
ink," it is meant the inks disclosed in U.S. Pat. No. 4,521,492,
the disclosure of which is incorporated herein in its entirety by
this reference. In a still further aspect, the colorants of the
invention herein do not comprise a metallic material. For example,
the colorants of the invention herein do not comprise an
aluminum-containing colorant. Yet still further, the colorants of
the present invention consist essentially of a non-leafing metallic
ink.
[0034] A grease, fat or oil-containing material can be packaged in
the packaging material. Upon storage, grease, fat or oil from the
packaged material may come in contact with the inner surface of the
substrate such that grease, fat or oil may migrate through the
substrate to be visible on an untreated outer surface of the
substrate. Also, grease, fat or oil may come into contact with the
outer surface of a packaging material during filling or storage of
the packaging material. It has been discovered that with the
present invention, the appearance of such grease stains may be
reduced or eliminated. As meant herein, "reduced" or "eliminated"
are terms that will be relative to the specific application. For
example, in a particular aspect, grease, fat or oil staining may be
totally "eliminated" when the package has a useful life of only
several weeks, whereas, grease, fat or oil staining may be
"reduced" in the same treated substrate if the useful life of the
package is several months. This is due to the fact that the present
invention generally does not result in the formation of an
impermeable barrier on a packaging material. Rather, it is believed
that through a combination of optical phenomena and formulation
selection, the surprising and unexpected masking properties of the
present invention are obtained.
[0035] In a further aspect, the dark colorant may comprise one or
more of: carbon black, raw sienna, burnt sienna, burnt umber,
chrome black, high purity furnace black, black azo dyes or brown
azo dyes. In a still further aspect, the dark colorant comprises
carbon black. While such masking many not be permanent in most
circumstances, the duration and extent of masking is sufficient for
packaging materials uses.
[0036] In a further aspect, the light colorant comprises one or
more of: titanium dioxide, calcium carbonate, calcium silicate,
calcium sulfate, barium sulfate, natural clay, a synthetic clay,
magnesium oxide, magnesium silicate, zinc carbonate, zinc oxide and
plastic pigment. A titanium dioxide product particularly suitable
for use in the invention herein is Huntsman R-BC Slurry, a product
of Huntsman Trioxide, Salt Lake City, UT. Clays suitable for use in
the invention herein include, but are not limited to, kaolin
(grades 1, 2 etc.), delaminated clay and structured clay. Kaolin
clays particularly suited for the invention herein include Kaoprint
and Kaobrite, products of Thiele, Sandersville, Ga. In a further
aspect, the colorant does not comprise calcium carbonate. In a
further aspect, the light colorant does not comprise calcium
carbonate.
[0037] In a further aspect, the dark colorant may be optionally
applied from a dark colorant-containing solution. It should be
noted that the dark colorant-containing solution may normally
contain additional materials, including other colorants. These
additional materials may comprise materials such as titanium
dioxide, which, in addition to being a white colorant, may also act
as an opacifier. Thus, when opacity is desirable in the dark
colored layer, titanium dioxide can be included along with the dark
colorant. A further additional material in the dark colored layer,
as well as in the light colored layer, may comprise clay or calcium
carbonate, which, in addition to being white colorants, may also
act as extenders or opacifiers, whereby the amount of colorant to
be utilized in the solution may be reduced or eliminated. Thus, it
is contemplated according to the invention herein, that the dark
colorant-containing solution may also contain materials that are
referred to elsewhere herein or otherwise known as "light
colorants" or that are otherwise generally known to one of ordinary
skill in the art as "colorants." Thus, when utilized in conjunction
with the dark colorant herein, the purpose of these materials is
for a reason other than for conferring color, however, some color
may nonetheless be conferred by use of such materials.
[0038] In a significant aspect, the materials utilized in one or
more of the dark or light colored layers or to color one or more
plys of the substrate itself may be suitable for use in food, drug
or cosmetic applications. Such materials are specifically described
in Title 21 of the United States Code. More particularly, the
colorants that may be suitable for use in the invention herein are
described in Title 21, Section 178.3297 of the United States Code.
The disclosures of all referenced United States Code sections are
herein incorporated in their entireties by this reference. Other
materials, whether colorants or otherwise, may be suitable for use
in food, drug and cosmetic applications that are not specifically
delineated in the United States Code, particularly materials that
may be available outside of the U.S. and are suitable for use
therein. As such, it is contemplated herein that materials not
specifically set forth in the United States Code may be utilized in
the present invention.
[0039] One of ordinary skill in the art may further understand that
other non-food, drug or cosmetic approved colorants or other
ingredients may be utilized in accordance with the invention herein
according to the intended end-use for the packaging material, as
long as such colorants are not those utilized in non-leafing
metallic inks. For example, if the material to be packaged is a
grease, fat or oil-containing pesticide, it will not be necessary
for the materials utilized on the surface of the packaging
substrate to be acceptable for food, drug or cosmetic applications.
Further, even where the material to be packaged is food, drug or
cosmetic material, a wide range of additional colorants may be
utilized where such materials are acceptable for such
applications.
[0040] In one aspect, the dark colored layer may be applied from a
dark colorant-containing solution, wherein the dark
colorant-containing solution comprises from about 0.01 to about
20.0% by weight of the dark colorant as measured by total weight of
the solution. Still further, the dark colorant-containing solution
comprises from about 0.25 to about 4.0% by weight of the dark
colorant as measured by total weight of the solution. Yet still
further, the dark colorant may be present in the dark
colorant-containing solution at from about 0.01, 0.1, 0.25, 0.5,
1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0,
7.5, 8.0, 10.0, 12.0, 14.0, 16.0, 18.0 and 20.0% by weight of the
dark-colorant-containing solution, where any of these stated
amounts may comprise either the upper or lower endpoint of the
range of dark colorant therein and any lower endpoint can be used
with any upper endpoint.
[0041] In a further aspect, the light colored layer may be applied
from a light colorant-containing solution, wherein the light
colorant-containing solution comprises from about 30 to about 90%
by weight of the light colorant as measured by total weight of the
solution. Still further, the light colored layer may be applied
from a light colorant-containing solution, wherein the light
colorant-containing solution comprises from about 40 to about 80%
by weight of the light colorant as measured by total weight of the
solution. Yet still further, the light colorant may be present in
the light colorant-containing solution at from about 1, 5, 10, 25,
30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 99% by
weight of the light colorant-containing solution, where any of
these stated amounts may comprise either the upper or lower
endpoint of the range of light colorant therein and any lower value
can be used with any upper value.
[0042] In a significant further aspect, either or both of the
colored layers may be applied from respective light or dark
colorant-containing solutions, wherein either or both solutions may
be aqueous. By having aqueous systems as defined previously,
standard paper mill equipment may be readily utilized to prepare
packaging materials according to the invention herein. This
provides significant advantages in the present invention over the
methods disclosed in U.S. Pat. No. 4,521,492.
[0043] In one or more aspects of the present invention, the dark
colored layer may not be separately applied to the substrate. If no
dark colored layer is separately applied, the substrate itself may
have a substrate color that is darker than the light colored layer.
In such an aspect, the substrate color is modified to be darker
than the uncolored (natural) substrate. For example, a dark color
can be added to one or more layers (or plys) in a single or
multi-ply paperboard by means of a colorant addition step during
the paper manufacturing process so that the entire substrate (in a
single ply product) or the outer surface of the paperboard (in a
multi-ply product) is darker than that of uncolored substrate. In
one aspect, a multi-ply paperboard article may be manufactured
whereby the pulp comprising one or more outer plys, for example,
the top liner, is treated with a dark colorant to result in a dark
colored outer surface for the substrate. In separate aspects, the
number of plys in the paperboard (whether colored or uncolored) is
two, three, four, five, six, seven, eight, nine or ten, in which
one or more outer plys may be colored with a dark colorant
according to the present invention. Such dyes or colorants may be
present in a pulp slurry in a range of from about 0.1 to about 3.0%
by weight. Such colorants may in the form of azo dyes wherein the
individual colors may be used alone or mixed with other azo dyes to
form a dark color in one or more plys of the paperboard. In a
further aspect, the entire paperboard product may be dark colored
by the addition of azo dyes to a pulp slurry in the amounts of from
about 0.1 to about 3.0% by weight.
[0044] Methods of making paperboard products are not crucial to the
invention herein and are well known generally to one of ordinary
skill in the art. Specific examples of methods that may be utilized
herein are described generally in U.S. Pat. Nos. 4,753,710,
4,913,773 and 5,169,496, the disclosures of which are each
incorporated herein in their entireties by this reference.
[0045] As contemplated herein, the specific shade of dark colorant
or light colorant is not crucial to the invention. However, as
noted, the "dark" colorant should provide a color to the substrate
that is darker than that provided by the "light" colorant to the
light colored layer and vice versa.
[0046] In one aspect, the light colored layer may be white and the
dark colored layer may be black or gray. In further aspects, the
light colored layer may be yellow, pink, pale green, pale blue,
etc.; that is, the light colored layer may be any color that
exhibits a significant reflectance of light. The dark colored layer
may be blue, purple, brown, etc.; that is, the dark colored layer
may be any color that exhibits a significant absorbance of light.
Definitions of "light colored" and "dark colored" are as previously
set forth herein.
[0047] While not wishing to be bound by theory, it is believed that
by selecting an outer substrate color that is closer in color to
that of a grease, fat or oil stain, the appearance of a grease, fat
or oil stain on the outer surface of the packaging material will be
lessened, reduced or eliminated. That is, it is hypothesized by
normalizing the background color of the packaging material to a
shade similar to the grease, fat or oil, the refractive index of
the packaging substrate may be altered so that a grease, fat or oil
stain may be less visible in the finished packaging material.
Further, selection of the light colored layer will be dependent on
a number of factors including the degree of darkness of the dark
colored layer and the desired whiteness/brightness of the outer
layer.
[0048] It should be noted that a very dark colored layer itself
will likely be effective to mask a wide variety of grease, fat or
oil stains or a substrate. However, one of ordinary skill in the
art will recognize that such a dark layer will be difficult to
cover with a light-colored over layer without having a very thick
layer and/or having a large amount of opacifying pigments, such as
TiO.sub.2. However, according to the method and compositions of the
present invention, it is possible to mask grease, fat or oil
staining by means of selection of the dark colored and light color
layers to provide cost effective packaging materials.
[0049] Accordingly, when a light colored layer is selected and
applied over the dark colored substrate or the dark colored layer,
the masking may be effectuated by the application of the light
colored outer layer. In accordance with the present invention, and
in some aspects in conjunction with binder materials (as discussed
in more detail below), it is believed that this optical phenomenon
is augmented and enhanced in a surprising and unexpected
manner.
[0050] In the selection of the colors so as to mask the appearance
of grease, fat or oil permeation (e.g. staining) in a packaging
material, the relative thickness of the colored layers, the
concentration of colorants in the coatings, the type of grease, fat
or oil-containing material being packaged and the time and the
temperature to which the package is subjected will each be
relevant. For example, when the grease masking capability of a
packaging material need only be apparent for a short time, such as
with a fast food container in which the packaged material may be
consumed shortly after purchase, a dark color may not need to be as
dark and a light color may not need to be as light relative to each
other because the grease masking necessity for the package is
relatively short-lived. In contrast, when packaging a food product
where the storage capability needs to be longer, the dark color
and/or the light color may need to have a greater masking ability.
Moreover, the degree of a grease, fat or oil stain will also be
related to the type of material being stored in the packaging
material. However, in accordance with the disclosure herein and the
general knowledge in the art, one of ordinary skill in the art will
be able to determine the relative amounts of ingredients, thickness
of coatings, etc. useful for particular applications without undue
experimentation.
[0051] In a still further aspect, the packaging material may have a
TAPPI brightness number of from about 50, 55, 60, 65, 70, 75, 80,
85, 90, 95, 99 or 100, where any of these referenced measurements
may comprise either the upper or lower endpoint and any of these
lower endpoints may be used with any of these higher endpoints. In
a further aspect, the packaging material may have a TAPPI
brightness number of from about 60 to about 90. Still further, in
another aspect, the packaging material has a TAPPI brightness
number of greater than 75. The brightness of the packaging
materials are measured according to TAPPI method T452 om-83. This
TAPPI method is incorporated herein in its entirety by this
reference.
[0052] In a further major aspect, the grease, fat or oil permeable
substrate utilized according to the compositions and methods herein
comprises paperboard, paper or fabric. However, one of ordinary
skill in the art will recognize that the substrates in which this
invention may be utilized are not limited to these specifically
enumerated substrates. Rather, it is contemplated according to the
invention herein "substrate" includes any article that customarily
or feasibly could be coated with a coating formulation or that may
itself be dark colored and may be coated with the light colored
layers described herein. In separate aspects, the substrate must be
suitable for use as a packaging material as the term is defined
elsewhere herein.
[0053] Still further, in another aspect, the grease, fat or oil
permeable substrate may comprise paperboard. The paperboard so
utilized can specifically comprise one or more of: SBS ("solid
bleached sulfate"), SUS ("solid unbleached sulfate") or recycled
paperboard.
[0054] SUS (for example, Omnicoat.RTM. or Pearlcoat.RTM.,
Riverwood, Marietta, Ga.) utilized according to the methods herein
may be comprised of primarily southern pine species such as the
Loblolly as a fiber source, although some hardwood fiber may be
used, particularly in one or more outer plys. Some recovered paper
may also be added as a fiber source, which may account for about
20% of the fiber (although this amount will vary based on market
conditions and other factors). SUS is generally a brown-colored
paperboard which can then be coated according to the methods herein
with application of a dark colored layer proximal to the SUS and a
light colored proximal to the dark colored layer. Additionally, one
or more outer plys of the SUS may be colored to result in a one or
more dark colored outer plys on the paperboard.
[0055] When recycled paperboard (for example ClassicNews.RTM.,
Rock-Tenn Company, Norcross, Ga.) is utilized in the compositions
and methods herein, a variety of types of recovered paper and
paperboard may be utilized. Each source may have an impact on the
final substrate and, accordingly, the packaging applications to
which the packaging material is suited. Two of the predominant
fibers utilized in recycled paperboard sources may be old
newspapers (ONP) and old corrugated containers (OCC). ONP normally
add bulk and can improve formation but may not convey as much
strength as OCC. Another common fiber source may be office waste
paper (OWP) which has high value when utilized as an outer (top)
ply to provide a clean, smooth printing surface for the coated
recycled paperboard. This outer ply may be made dark colored
according to the methods of the invention herein. Recycled
clippings from printing and converting plants also can provide a
large fiber source for the recycled coated paperboard industry.
[0056] SBS (for example, from Westvaco, Covington, Va.) that may be
utilized according to the methods and compositions herein generally
comprises bleached fiber from both softwood and hardwood trees,
although there normally is a higher percentage of hardwood fiber
therein. The percentage of hardwood fiber can vary significantly
without affecting its use in the invention herein, but, typically,
the hardwood content may be greater than about 80%. SBS utilized
according to the methods herein may also contain some recycled
fibers. When matted into paperboard according to known papermaking
procedures, hardwood fibers generally form a smooth white sheet. As
such, without treatment with the grease masking method herein, the
appearance of grease, fat or oil staining on this SBS substrate
will be marked. In a significant aspect, the packaging material
prepared according to the invention herein may be suitable for use
in packaging food, drugs or cosmetics. More particularly, the
packaging material may be suitable for use in packaging human food
or animal food.
[0057] In addition to paperboard as described above, the substrate
may be paper or fabric. If the substrate is paper or fabric or some
other suitable substrate, it will be understood that the substrate
itself may be dark colored or a separate dark colored outer layer
may be applied to accomplish the objectives of the present
invention. When paper, the packaging material may be in the form of
a single layer or in a multi-ply bag. Application of the dark and
light colored layers to both paper and fabric materials is in
accordance to the methods disclosed herein with respect to
paperboard. To the extent that the application methods may differ,
such differences will be minimal and one of ordinary skill in the
art will recognize the same.
[0058] In a further aspect, the colorant-containing solutions from
which one or more of the dark colored layers and the light colored
layers are applied each, independently, comprise one or more of:
water, dispersant, resin, surfactant, wetting agent, defoamer,
thickener, starch, preservative, or antioxidant. Such additional
materials may be included in the colorant-containing solutions
according to methods known generally to one of ordinary skill in
the art. Non-exclusive examples of coating formulations that may be
utilized in accordance with the invention herein are disclosed
generally in U.S. Pat. No. 5,837,383, the disclosure of which is
incorporated herein in its entirety by this reference.
[0059] Furthermore, there may be a layer on the outer surface of
the grease, fat or oil-permeable substrate, wherein the layer
comprises one or more of: starch, polyvinyl alcohol, or one or more
sizing agents that would be recognizable by one of ordinary skill
in the art. When starch is utilized in the present invention, the
starch may be catatonically modified to augment the affinity of the
precoat to the substrate that, if comprised of paper or paperboard,
may carry a net anionic charge. Still further, in another aspect,
the layer may comprise a dye, pigment or other type of colorant,
and, as such, this layer may operate as the dark colored layer.
This layer, whether colored or not, may or may not comprise
binder.
[0060] Still further, in another aspect, a printed layer may be
present adjacent to an outer surface of the light colored layer.
Such methods of printing are well known to one of ordinary skill in
the art and, as such, are not described herein in detail.
[0061] With respect to the dark colored layer aspect of the
invention, the following method may be utilized. After preparation
and drying of the packaging substrate, a dark colorant containing
solution, for example, comprising starch, dark colored pigment and
water can be applied on a wet stack calendar (in addition to or
instead of applications on a size press for Fourdrinier machines).
The wet stack may consist of a stack of rollers, which may be from
five or seven rollers high. The web may then be threaded through
this stack. Water boxes containing the percent solution may be
placed adjacent to one roller for the topside of the web and
another roller for the bottom side of the web. The dark colored
layer can be applied to the web as the web passes the water
boxes.
[0062] In separate aspects, the dark colored layer may be adjacent
to the substrate and the light colored layer may be adjacent to the
dark colored. Still further, the dark colored layer may be proximal
to the substrate and adjacent to the light colored layer. Still
further, the dark colored layer may be proximal to the substrate
and the light colored layer may be proximal to the dark colored
layer.
[0063] In addition to the previously described layers, a barrier or
fixing layer separate from the light and or dark colored layer may
be added at any location on the packaging material without
detracting from the purposes of the present invention. For example,
a clear barrier or fixing coat may be disposed between the outer
surface of the substrate and the dark colored layer, between the
dark colored layer and the light colored layer or may be disposed
on the surface of the light colored layer before or after the
application of a printed layer, if any.
[0064] As noted, binders may be useful in the light and/or dark
colorant-containing solutions herein and will be present in binder
solutions as binder solids as discussed below. Binders suitable for
use in the first or light colored solutions herein may comprise
naturally- or synthetically-derived materials.
[0065] In particular aspects, suitable synthetic binders may
comprise latex polymers, wherein such latex polymers are derived
from monomers comprising one or more of: acetoacetoxy ethyl
methacrylate, acetoacetoxy ethyl acrylate, methyl acrylate, methyl
methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate,
butyl methacrylate, isobutyl acrylate, isobutyl methacrylate,
ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-ethyl hexyl
acrylate, isoprene, octyl acrylate, octyl methacrylate, iso-octyl
acrylate, iso-octyl methacrylate, trimethyolpropyl triacrylate,
styrene, .alpha.-methyl, glycidyl methacrylate, carbodiimide
methacrylate, C.sub.1-C.sub.18 alkyl crotonates, di-n-butyl
maleate, .alpha.-or-.beta.-vinyl naphthalene, di-octylmaleate,
allyl methacrylate, di-allyl maleate, di-allylmalonate,
methyoxybutenyl methacrylate, isobornyl methacrylate,
hydroxybutenyl methacrylate, hydroxyethyl(meth)acrylate,
hydroxypropyl(meth)acrylate, vinyl acetate, vinyl ethylene
carbonate, epoxy butene, 3,4-dihydroxybutene,
hydroxyethyl(meth)acrylate, methacrylamide, acrylamide, butyl
acrylamide, ethyl acrylamide, vinyl(meth)acrylates, or
isopropenyl(meth)acrylate. In particular, suitable latexes may
include one or more of: styrene butadiene (SBR), polyvinyl acetate,
polyvinyl acetate-acrylate, ethylene vinyl acetate, styrene
acrylates, polyacrylates and acrylic materials. Still further,
naturally derived binders may be used in the present invention.
Such binders may include, but are not limited to, soy or animal
protein materials.
[0066] One of ordinary skill in the art will recognize that such
binders may be useful in the methods of the present invention to
assist in holding the colorant particles together and to the
packaging substrate. The type of binder utilized in the methods of
the present invention may vary depending on the particular colorant
utilized, the packaging substrate and the intended end use for the
packaging material. For example, SBR binders typically provide very
good binding strength, gloss, ink holdout, and flexibility. PVAc
binders can provide good gluing properties, brightness stability,
ink receptivity, and low odor. Protein binders may contribute to
appearance, gloss, fountain solution acceptance, and
glueability.
[0067] As for binder amounts to be included in the solutions, a
binder may be present in the dark and/or light colorant-containing
solutions in an amount of from about 17 to about 60% by weight of
each individual colorant-containing solution. Still further, the
binder may be present in the dark and/or light colorant-containing
solutions in an amount of from about 17 to about 37% by weight of
each individual colorant-containing solution. Still further, the
amount of binder may be from 23% to 40% by weight of each
individual colorant-containing solution. In a further aspect, the
binders may be present at from about 25% to about 35% by weight of
each individual colorant-containing solution. Still further, the
binders may be present in the individual colorant-containing
solutions in the amount of from about 20, 25, 30, 35, 40, 45, 50,
55, 60, 65 or 70% by weight of each individual colorant-containing
solution, where any of these values may form the lower endpoint and
the upper endpoint and any lower value may be utilized with any
upper value. In a further aspect, the amount of binder is greater
than 17% by weight. One of ordinary skill in the art will recognize
that such binder materials are often supplied as % solids in
liquid. The values recited herein are measure as total dry weight
under solids used in the coating compositions.
[0068] In further aspects, a mixture of synthetically and naturally
derived binders may be utilized in the individual colorant
containing solutions. In one non-limiting aspect of the invention,
the individual colorant containing solutions may comprise a mixture
of latex polymer binder and animal and/or vegetable protein,
wherein the total amount of binder in the acting composition is
measured by the sum of the weight percent of latex polymer solids
and the soy protein solids. In a further aspect, the ratio of latex
polymer to animal and/or vegetable protein is from about 2:1 to
about 20:1, or from about 2:1 to about 10:1, where the total amount
of binder in the individual colorant containing solutions is as
stated previously. Still further, the ratio of latex polymer to
animal and/or vegetable protein is from about 7:1 to about 12:1,
where the total amount of binder in the individual
colorant-containing solutions is stated previously. Yet still
further, the ratio of latex polymer to animal and/or vegetable
protein is from about 3:1, 5:1, 7:1, 9:1, 10:1, 11:1, 13:1, 15:1,
17:1, 19:1, where any lower value may be paired with any upper
value and where the total amount of binder in the individual
colorant-containing solutions is as stated previously.
[0069] In one aspect, the dark colored layer does not comprise
binder and the light colored layer comprises binder. In a further
aspect, the dark colored layer comprises binder and the light
colored layer does not comprise binder. Still further, in another
aspect, each of the colored layers comprise binder.
[0070] Although the amounts of components in the individual
colorant solutions are recited above, it should be noted that the
amount of pigment, binder and/or other ingredients, will be, in
part, affected by factors such as the base color of the substrate
and the amount and duration of the grease masking needed in a
particular application. For example, where recycled paperboard or
SUS board stock is utilized as a substrate, the base color of the
substrate will be darker (or less white). Accordingly, the amount
of pigment in the light colored layer(s) may need to be higher in
order to satisfactorily hide the color of the substrate. In
contrast, if SBS is utilized as the substrate, the amount of light
colored pigment needed in the light colored layer(s) may be lower
than that needed for a darker colored substrate because this
substrate is less dark in color.
[0071] Moreover, while the specific type of binder(s) utilized in
the present invention has not been found to be crucial to the
present invention, one of ordinary skill in the art would recognize
that the amount of pigment in the colorant containing solutions
should directly affect the amount of binder to be included in the
solutions. Thus, where a lower amount of light colored pigment is
utilized (as discussed above), a proportionally lower amount of
binder will be necessary. However, in accordance with the grease,
fat or oil masking compositions and methods of the present
invention, the amount of binder needed for a particular application
has been found to be in excess of the amount of binder utilized for
that same particular application where no grease, fat or oil
masking properties are present.
[0072] The dark and light colored layers may be applied utilizing
existing methods of applying coatings to packaging substrates. Such
methods and compositions useful herein are known generally to one
of ordinary skill in the art of packaging material manufacture and,
as such, are not described in detail herein. Methods and
compositions that may be utilized according to the invention herein
are disclosed in U.S. Pat. Nos. 3,196,038, 3,873,345, 4,265,969 and
4,301,210, the disclosures of which are each incorporated herein in
their entireties by this reference.
[0073] Further specific examples of coating methods that may be
utilized include the following.
[0074] In a major aspect, an in-line coating method maybe utilized
to reduce the cost of the coating process, however, in another
aspect an off-line process may be utilized. Coating processes that
may be utilized include, but are not limited to: roll coating,
rigid blade, straight blade or bent blade, air knife or a
combination of coaters. Additionally, the compositions of the
invention may be applied utilizing rotogravure and flexographic
methods.
[0075] Roll coaters will generally not be utilized as a stand-alone
coating method but may be used as the applicator roll in each of
the coating processes discussed below. One of ordinary skill in the
art will recognize that roll coaters operate similarly to a roller
one uses to paint a wall at home. That is, in one aspect, the roll
may rotate in a vat of coating and continues to rotate until it
comes into contact with the paperboard and applies the wet coating
thereto. The wet coating may then immediately be removed by either
a blade, rod, or air knife.
[0076] A blade coater may be utilized to remove excess coating by
use of a rigid (straight) or bent blade. In either aspect, the
blade may actually contact the paperboard and scrape off the excess
coating. Blade coaters will generally leave more coating in the low
areas (valleys) and less coating on the high areas (hills) of the
paperboard.
[0077] Blade coatings may be utilized to level off and seal the
paperboard. Blade coatings generally augment paperboard smoothness
and may be preferable for some end uses. A typical blade coater
will generally apply from about 1 to 2 dry pounds of coating per
1000 square feet. Blade coaters are generally utilized to apply
base coating (primers) as well as top coatings to seal the sheet.
Blade coaters are particularly useful when the packaging substrate
utilized herein is SBS.
[0078] A rod coater may be utilized according to the invention
herein to remove excess coating with a smooth or wire wound rod.
The rod may be placed in a holder and may be slowly rotated as
coating is wiped away. One of ordinary skill in the art will
recognize that a rod coater operates similarly to a blade coater in
that it generally levels and seals the sheet, but may also follow
the natural contour of the paperboard surface. Rod coaters can be
considered to allow a greater margin for error than a blade coater,
in that small impurities that can cause scratches and streaks in
the blade process are more likely to pass under the rod and not
cause these defects. For this reason, rod coaters will be useful in
the present invention when the packaging substrate comprises
recycled paperboard and or SUS. Rod coaters will generally apply
from about 1 to 3 dry pounds of coating per 1000 square feet.
[0079] In a further aspect, an air knife coater may be utilized to
remove excess dark and/or light colored layer by the blowing of a
thinjet of air on the wet coating. The air knife generally leaves a
more uniform film thickness of coating across the entire web by
following the contour of the sheet. Thus, if the surface of the
packaging substrate is rough, it will remain rough. If it is
smooth, it will generally remain smooth. Because of its excellent
uniformity and its greater thickness, air knife coatings may be
utilized when an opaque coating is desired. Air knife coatings are
particularly useful for coating SBS and recycled paperboard.
Typical air knife coaters will generally apply about 2 to about 6
dry pounds of coating per 1000 square feet.
[0080] In accordance with the methods herein, two, three or more
coating units may be utilized to prepare the packaging material. In
one aspect, the use of multiple coating methods may allow improved
smoothness of the surface of the packaging material and may
generally allow improved printability. One of ordinary skill in the
art will recognize that various combinations may be utilized
depending on the characteristics of the packaging substrate and the
performance and cost attributes desired in the finished packaging
material.
[0081] It will be recognized that when applied from a
colorant-containing solution, the one or more colored layers are
applied wet and should normally be dried. Drying of the packaging
materials can be accomplished using either forced air or infrared
dryers. In some cases both methods may be used.
[0082] In a further aspect, the coated packaging material may be
dry calendered either before or after the application of a printed
layer, if one is desired. One of ordinary skill in the art will
recognize that dry calendering is a process of polishing the coated
substrate and of controlling caliper and density of the finished
surface. Calender finishing is generally performed to improve
smoothness and increase gloss of the finished packaging material.
In accordance with the present invention, a stack of calendar rolls
may be utilized; this is generally referred to as "hard nip
calendering." Alternatively, gloss calenders having a
highly-polished, heated cylinder that is loaded against a resilient
rubber backing roll may be utilized. As the packaging substrate
outer surface comes into contact with the polished hot roll and
enters the calender nip (between the two rolls), a slight change in
speed may occur which results in a polishing of the coating. This
process is referred to as "soft nip calendering." Methods of
calendering are known generally to those of ordinary skill in the
art. Non-exclusive examples of calendering are disclosed in U.S.
Pat. No. 5,029,521, the disclosure of which is incorporated herein
in its entirety by this reference.
[0083] In a further major aspect of the invention herein, the dark
colored layer and light colored layer each, independently, may
comprise one or more of: polyethylene, polyester, polypropylene,
polystyrene, or halogenated or non-halogenated vinyl polymers. Such
materials may also be considered, in some aspects, to comprise
binder materials. With respect to the polyethylene aspect, suitable
polyethylenes include HDPE, MDPE, LDPE, LLDPE, homogenously
branched linear ethylene polymers and substantially linear ethylene
polymers. Such materials may also be considered, in some aspects,
to comprise binder materials. In this aspect, the dark colored
layer and the light colored layer each, independently, may comprise
from about 5 to about 40% colorant as measured by total weight of
each individual layer. Still further, the dark colored layer and
the second layer each, independently, may from about 5, 10, 15, 20,
30, 40, 45, and 50% colorant, where any of these numbers may
comprise either endpoint for the amount of colorant and any lower
endpoint may be utilized with any upper endpoint. While any of the
above-described colorants may be utilized in this aspect of the
invention, in one further particular aspect, the light colorant may
comprise titanium dioxide and the dark colorant may comprise carbon
black.
[0084] In this aspect of the invention, a grease, fat or oil
permeable substrate having an outer surface is provided whereby a
dark colored layer may be extruded onto the outer surface of the
substrate and a light colored layer may be simultaneously or
sequentially extruded onto an outer surface of the dark colored
layer. Alternatively, a paperboard material may be utilized wherein
one or more layers (plys) of the paperboard are colored with a dark
colorant. In this latter aspect, a one or more colored layers may
be extruded onto the outer surface of the colored paperboard with
or without application of a precoat layer.
[0085] Methods of extrusion coating packaging materials are known
generally to one of ordinary skill in the art, and, as such, need
not be described in detail herein. Non-exclusive examples of
extrusion coating methods that may be utilized according to the
invention herein are described generally in U.S. Pat. Nos.
4,343,858 and 4,455,184, the disclosures of which are each
incorporated herein in their entireties by this reference.
[0086] In a further aspect, one or more of the colored layers may
be extruded either simultaneously or sequentially to form a
laminate material. This laminate material may be applied to the
outer surface of the substrate of the invention herein to form
either or both of the colored layers.
[0087] In still a further aspect, a dark colored layer may be
applied to the substrate and a light color layer may be extruded to
the dark colored surface. For example, a dark colored layer having
an inner and an outer surface may be applied from a dark
colorant-containing solution as set forth above. A light colored
layer having an inner and an outer surface may then be extruded
thereto. Alternatively, a dark colored paper or fabric may be
applied to a paperboard, paper or fabric substrate and a light
colored layer extruded thereto.
[0088] The substrates treated according to the present invention
may be utilized in a number of different applications. In specific
non-limiting examples, packaging materials in the form of a box,
cup, tray, plate, can, tube, bottle or other container form may be
prepared. Materials packaged therein may be consumer goods. In
separate examples, the packaging materials may be used for both
food and non-food packaging. As examples of food that may suitably
be packaged in materials treated with the compositions and methods
of the present invention, the following non-limiting examples are
presented: sweets, chocolate, confectionery, pastries, biscuits,
dairy products (e.g, butter and cheese), powdery foodstuffs (e.g.,
coffee, tea, cocoa, flour, cereals), frozen food (e.g., ice cream,
pastries, vegetables, seafood), fresh and semipreserved foods, pet
food or carryout foods. Non-limiting examples of non-food packaging
that may suitably be packaged in materials treated with the
compositions and methods of the present invention include:
cosmetics, toiletries, pharmaceuticals, cigarettes, detergents,
textiles, toys, games, tools, household appliances, pesticides,
fertilizers, hobby items, paper products, cassettes, record
sleeves, and auto parts.
[0089] Converting methods known generally in the art may be
utilized to form the packaging materials of the present invention.
For example, the packaging material may be fabricated into a box
configuration, a tube (shell) configuration, a tray configuration,
or a bottle wrap configuration. These recited examples are meant to
be illustrative only and one of ordinary skill in the art would
recognize that the types of packaging materials that may be
fabricated utilizing the grease, fat or oil masking compositions of
the present invention may encompass a wide variety of
configurations. Moreover, one of ordinary skill in the art would
recognize conventional converting methods (i.e., cutting, creasing,
and gluing) are suitable for use in conjunction with the present
invention.
[0090] Experimental
[0091] The following examples are put forth so as to provide those
of ordinary skill in the art with a complete disclosure and
description of how the compounds, compositions, articles, devices,
and/or methods claimed herein are made and evaluated, and are
intended to be purely exemplary of the invention and are not
intended to limit the scope of what the inventors regard as their
invention. Efforts have been made to ensure accuracy with respect
to numbers (e.g., amounts, temperature, etc.) but some errors and
deviations should be accounted for. Unless indicated otherwise,
parts are parts by weight, temperature is in .degree. F. or is at
ambient temperature, and pressure is at or near atmospheric.
[0092] Bending chip recycled paperboard ("uncoated box board") was
utilized in the examples.
[0093] Suitable formulations for use in the present invention are
set forth in Tables 1 and 2 below.
[0094] Various grease, fat or oil-containing packaged goods were
tested in packaging materials treated with formulations of the
present invention, such as those described below. Such tests were
run for extended times and at elevated temperatures as
described.
[0095] All tests utilized grease, fat or oil-containing materials.
Where known, test results set forth below include the weight
percent of grease, fat or oil in the subject materials. However,
since some tested product were proprietary formulations, the amount
of grease, fat or oil within the product was unknown. In such
cases, grease, fat or oils that may be present in the tested
product are described.
1TABLE 1 Air Coating Method Material Supplier Product Name % solids
wet lbs dry lbs pigments Pigment Kaoline clay Theile Kaolin Company
KaoPrint 0.68 15 10.2 47.6% 68.8% TiO2 Trioxide Americas, Inc.
RR-BC slurry 0.75 15 11.25 52.4% Protein Protein Technologies
Pro-Code 427 0.15 8 1.2 3.8% Protein % Latex Rohm & Haas Res
3083 0.5 17 8.5 27.3% latex % Defoamer Nalco Chemical Company Nalco
8669 0.76 0.038 0.029 0.09% Water 0 5 0 60.04 31.18 31.1% Total %
comb Binder calc. Solids 52% 39.6 Parts latex 5.6 Parts protein
45.2 Parts binder
[0096]
2TABLE 2 Rod Coating Method Material Supplier Product name % solids
wet lbs dry lbs dry pigments Pigment Kaoline clay #1 Theile Kaolin
Company Kaobrite 0.68 15 10.2 45.8% 68.9% Kaoline clay #2 Theile
Kaolin Company KaoPrint 0.68 15 10.2 45.8% TiO2 Trioxide Americas,
Inc. RR-BC slurry 0.75 2.3 1.73 7.8% Black Various FDA listed
pigment 0.8 0.16 0.13 0.6% Latex Rohm & Haas Res 3083 0.5 20 10
31.0% Defoamer Nalco Chemical Company Nalco 8669 0.76 0.02 0.015
0.05% Thickener Alco Chemical Alcogum 149 0.354 0.078 0.028 0.09%
Water 0 5 0 calc. Solids 56.1% 44.9 Parts bunder
[0097]
3TABLE 3 COATING FORMULATIONS TESTED Coating Coating Coating
Coating Coating Coating Formula Formula Formula Formula Formula
Formula #1 #1A #1C #1D #2A #2B First Down (White/light) Top
Coating(s) Pigments Kaolin Clay 1 28.7% 35.2% 35.2% 35.2% 35.2%
35.2% Kaolin Clay 2 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% TiO2 71.3% 29.1%
29.1% 29.1% 29.1% 29.1% Total Pigment % 63.0% 64.3% 64.3% 64.3%
64.3% 64.3% Binders Soy Protein 2.5% 0.0% 0.0% 0.0% 0.0% 0.0% Poly
vinyl acetate 34.1% 35.6% 35.6% 35.6% 35.6% 35.6% latex Total %
comb. 36.6% 35.6% 35.6% 35.6% 35.6% 35.6% Binder Additives
Thickener 0.07% 0.0% 0.0% 0.0% 0.0% 0.0% Alcosperse 0.1% 0.0% 0.0%
0.0% 0.0% 0.0% Defoamer 0.25% 0.0% 0.0% 0.0% 0.0% 0.0% First down
(dark) coating Starch Cationic 5% 0 0 0 0 0 Black Pigment 0.6% 0.1%
0.2% 0.2% 0.51% 0.51% Water 94.40% 0.0 0 0 0 0 Pigments Kaolin Clay
1 0% 0.0% 0.0% 0.0% 0.0% 0.0% Kaolin Clay 2 0% 64.6% 64.6% 57.0%
60.3% 60.3% TiO.sub.2 0% 0.0% 0.0% 11.1% 6.4% 6.4% Total Pigment %
0% 64.6% 64.6% 68.1% 66.6% 66.6% Binders Soy Protein 0 0.0 0.0 0.0
0.0 0.0 Poly vinyl acetate 0.0 35.3% 35.2% 31.7% 32.8% 32.8% Latex
Total % comb. 0% 35.3% 35.2% 31.7% 32.8% 32.8% Binder Additives 0 0
0 0 0 0 Thickener 0 0 0 0 0 0 Dispersant 0 0 0 0 0 0 Defoamer 0 0 0
0 0 0 Coating Coating Coating Coating Coating Coating Formula
Formula Formula Formula Formula Formula #2C #5 #6 #7 #7-4B #8 First
Down (White/light) Top Coating(s) Pigments Kaolin Clay 1 35.2%
35.2% 17.6% 44.90% 44.9% 44.9% Kaolin Clay 2 0.0% 0.0% 0.0% TiO2
29.1% 29.1% 46.6% 18.1% 18.1% 18.1% Total Pigment 64.3% 64.3% 64.2%
63.0% 63.0% 63.0% % Binders Soy Protein 2.0% 2.9% 0.0% 2.5% 2.5%
2.5% Poly vinyl 33.0% 31.0% 35.6% 34.1% 34.1% 34.1% acetate laytex
Total % 35.0% 33.9% 35.6% 36.6% 36.6% 36.6% comb. binder Additives
Thickener 0.0% 0.31% 0.065% 0.07% 0.07% 0.07% Dispersant 0.0% 0.16%
0.12% 0.10% 0.10% 0.10% Defoamer 0.0% 0.04% 0.007% 0.25% 0.25%
0.25% First down (dark) coating Starch Cationic 0 0 0 0 5% 5% Black
Pigment 0.51% 0.15% 0.15% 0.2% 0.6% 0.6% Water 0 0.0 0.0 0.0 94.40%
94.40% Pigments Kaolin Clay 1 0.0% 31.0% 29.9% 30.2% 0% 0% Black
Pigment 0.51% 0.15% 0.15% 0.2% 0.6% 0.6% Water 0 0.0 0.0 0.0 94.40%
94.40% Pigments Kaolin Clay 1 0.0% 31.0% 29.9% 30.2% 0% 0% Kaolin
Clay 2 60.3% 31.0% 29.9% 30.2% 0% 0% TiO.sub.2 6.4% 5.0% 5.1% 5.1%
0% 0% Total Pigment 66.6% 67.0% 64.9% 65.5% 0% 0% % Binders Soy
Protein 0.0 0.0 0.0 0 0 Poly vinyl 32.8% 32% 35% 34% 0.0 0.0
acetate Latex Total % 32.8% 32.0% 35.2% 34.0% 0% 0% comb. Binder
Additives 0 0 0 Thickener 0 0.31% 0.15% 0.21% 0 0 Dispersant 0
0.16% 0.10% 0.00% 0 0 Defoamer 0 0.04% 0.15% 0.04% 0 0
[0098]
4TABLE 4 Masking of Packaging Material Contacted with Votive
Candles or Oil Impregnated Dusting Gloves Oil impregnated Dusting
Glove Substrate Votive Candles* (.about.5% mineral oil) Coating
Formula 1 Good - No outside Stack test staining and very little
Stored at 120 deg F. inside staining Evaluated at 31 days Coating
Formula 1 Good - No outside staining; Carton test very little to no
inside Stored at 120 deg F. staining Evaluated at 117 days Coating
Formula 1 Good - No outside staining; Carton test very little to no
inside Stored at TAPPI conditions staining (73 deg. F., 50%
humidity) Evaluated at 117 days *Composition of votive candles
unknown. Such candles are known to include petroleum (oily) waxes
and fragrance oils.
[0099]
5TABLE 5 Masking of Packaging Materials Contacted with Various Cat
Food Formulations Cat Food Formula I Cat Food Formula II Substrate
(.gtoreq. 10% Fat Content) (.gtoreq. 14% Fat Content) Coating
Formula 1 Good - No outside staining; Good - No outside staining;
Hand filled Carton test Moderate inside staining; Moderate inside
staining; Stored at 120 deg F. no staining to corrugated no
staining to corrugated Evaluated at 61 days under carton under
carton Coating Formula #7-4B Good - No outside staining; Pile test
Moderate inside staining Stored at 120 deg F. Evaluated at 117 days
CCNB (comparative) Poor staining Poor staining Pile test Stored at
120 deg F. Evaluated at 21 days Low density Polyethylene Poor -
Inside edge wicking Poor - Inside edge wicking Extruded CCNB
Paperboard Clear Inside Poly (1/2 mil inside) (comparative) Stored
at 120 deg F. Evaluated at 21 days White Outside low density Poor -
Outside staining Poor - Outside staining Polyethylene extrusion
visible visible coated CCNB - (comparative) Stored at 120 deg F.
Evaluated at 21 days White 2-sided low density Poor - Inside edge
wicking Poor - Inside edge wicking Polyethylene extrusion coated
CCNB (comparative) Stored at 120 deg F. Evaluated at 21 days
Metalized Polyester Film Good - Inside staining, no Good - Inside
staining, no laminated to CCNB outside staining outside staining
(comparative) Stored at 120 deg F. Evaluated at 21 days Coating
Formula #1A, 1C, Good - Slight inside Good - Slight inside stain;
1D Stored at 120 deg F. staining, no outside staining shiny area on
outside where Evaluated at 21 days product was piled (not a stain
appearance) PM Good - Inside edge Good - Inside edge Stored at 120
deg F. wicking, no outside staining wicking, no outside staining
Evaluated at 21 days
[0100]
6TABLE 6 Masking of Packaging Materials Contacted with Various Dog
Snack Formulations Dog Dog Snacks Snacks Dog Dog Snacks Dog Snacks
Formula Formula Snacks Formula 1 Formula II III IV Formula V
(.gtoreq.4% Fat (.gtoreq.3% Fat (.gtoreq.6% Fat (.gtoreq.6% Fat
(.gtoreq.14% Fat Substrate content) content) content) content)
content) Coating Good-No Formula 1 outside Machine filled stains;
Carton test moderate Stored at 120 inside deg F staining Evaluated
at 61 days RF2 Poor- (comparative) Moderate Machine filled staining
Carton Test seen on Stored at 120 printed deg F side; Evaluated at
61 moderate days inside staining Coating Good-No Good-No Formula 1
outside outside Hand filled staining; no staining; carton test
staining on moderate Stored at 120 corrugated inside deg F under
staining; no Evaluated at 72 carton staining to days corrugated
under carton RF2 Poor- Poor- (comparative) Several Many oil Test
stains on droplet Stored at 120 printed stains on deg F side; no
printed Evaluated at 72 staining to side; days corrugated moderate
under inside carton staining, no staining to corrugated under
carton Coating Good-no Formula #7-4B outside Pile test staining,
Stored at 120 moderate deg F inside Evaluated at staining 117 days
CCNB Good-No Good-No Marginal- Poor-1/4" Poor- (comparative) inside
or inside or No major stains in Staining all Hand-filled outside
outside staining, several over the cartons Stored staining staining
several areas of the outside of at 120 deg F small spots carton the
carton Evaluated at 21 of staining days Low density Good-No Good-No
Good-No Good-No Poor- Polyethylene edge edge edge edge Edge
Extruded (1/2 wicking or wicking or wicking or wicking or staining
mil inside) staining staining staining staining CCNB Paperboard
(comparative) Pile Test Stored at 120 deg F Evaluated at 21 days
Coating Good-No Good-No Good-No Good-No Good-No Formula outside
outside outside outside outside #1D staining staining staining
staining staining Pile test Stored at 120 deg F Evaluated at 21
days PM Good-No Good-No Good-No Good-No Good-No Pile Test outside
outside outside outside outside Stored at 120 staining staining
staining staining staining deg F Evaluated at 21 days
[0101]
7TABLE 7 Masking of Packaging Materials Contacted with Hand Lotion*
Lotion Product Lotion Drop Test Lotion Stack Storage Test (3
Substrate (7 hours) Test (3 weeks) weeks) Coating Formula #8 Good -
No outside Good - No Good - No outside Hand filled Carton staining
outside staining staining Stored at 120 deg F. Coating Formula #7-
Good - No outside Good - No 4B staining outside staining Stored at
120 deg F. Coating Formula #6 Good - No outside Good - No Stored at
120 deg F. staining outside staining Coating Formula #5 Good - No
outside Good - No Stored at 120 deg F. staining outside staining
Coating Formula Good - No outside Good - No #2A, 2B, 2C staining
outside staining Stored at 120 deg F. Coating Formula #1- Good - No
outside Good - No 1A, 1B, 1C staining outside staining Stored at
120 deg F. *Lotion formulation unknown, but hand lotions known to
contain moderate amounts of oils, including mineral oil.
[0102]
8TABLE 8 Masking of Packaging Materials Contacted with Biscuit Mix
Substrate Biscuit Mix (.gtoreq. 14% Fat Content) Coating Formula 1
Good - No outside staining; Light inside Hand filled carton test
staining; no staining to corrugated under Stored at 120 deg F.
carton Evaluated at 72 days RF1 (comparative) Good - No outside
staining; no staining to Machine filled Carton test corrugated
under carton Stored at 120 deg F. Evaluated at 72 days Coating
Formula #7-4B Good - No outside staining, Light inside Pile Test
staining Stored at 120 deg F. Evaluated at 117 days CCNB
(comparative) Poor staining Pile test Stored at 120 F. Evaluated at
26 days Low density Polyethylene Good - No staining or edge wicking
Extruded CCNB Paperboard (1/2 mil inside) (comparative) Pile Test
Stored at 120 deg F. Evaluated at 26 days GM (comparative) Poor -
Light staining through the board Pile test Stored at 120 deg F.
Evaluated at 26 days 2 sided White Low density Good - No staining
or edge wicking Poly CCNB (comparative) Pile Test Stored at 120 deg
F. Evaluated at 26 days White outside Poly Poor - Significant
staining (comparative) Pile Test Stored at 120 deg F. Evaluated at
26 days
[0103]
9TABLE 9 Masking of Packaging Materials Contacted with Lotion
Impregnated Tissues* Lotion-containing Substrate Tissues Coating
Formula 1 Good - No outside Hand filled carton Test Stored at 120
F. staining Evaluated at 72 days Coating Formula 1 Good - No
outside Hand filled carton Test Stored at staining TAPPI conditions
(73 deg. F., 50% humidity) Evaluated at 72 days *Amount and
formulation of lotion in tissues unknown, but lotion compositions
known to contain moderate amounts of oils, including mineral
oils.
[0104]
10TABLE 10 Masking of Packaging Materials Contacted with Various
Cat Food Formulations Cat Formula III Cat Food Formula IV Substrate
(.gtoreq. 14% Fat content) (.gtoreq. 12% Fat content) Coating
Formula 1 Good - No outside staining; Carton test Stored at 120 F.
moderate inside staining; Evaluated at 72 days moderate staining at
one corner of carton to corrugated under carton Coating Formula
#7-4B Good - No outside staining; Piled test Stored at 120 F.
moderate inside staining Evaluated at 117 days CCNB (comparative)
Poor - Inside and outside Poor - Inside and outside Piled Test
Stored at 120 F. staining staining Evaluated at 183 days Coating
Formula #2C Good - No outside staining Good - No outside staining
Piled test Stored at 120 F. Evaluated at 183 days
[0105]
11TABLE 11 Masking of Packaging Materials Contacted with Various
Cat Food Formulations Cat Food Formula V (.gtoreq. 8% Fat Substrate
Content) Coating Formula 1 Good - No outside staining; Heavy
staining Carton test Stored at 120 F/ on inside of carton; Heavy
staining on Evaluated at 72 days corrugated under the carton RF2
(comparative) Marginal - No inside staining; slight Pile test
Stored at 120 F. staining on printed side of sample Evaluated at
117 days Coating Formula #7-4-B Good - No outside staining; Heavy
staining Piled test Stored at 120 F. on inside of paperboard
Evaluated at 117 days Low density Polyethylene Extruded CCNB Poor -
Pin-holing staining on carton; heavy Paperboard (1/2 Mil inside)
(comparative) edge wicking staining Hand-filled carton test Stored
at 120 F. Evaluated at 21 days Coating Formula #2A, 2B, 2C Good -
No outside staining; Heavy staining Filled Carton test Stored at
120 F. on fiber side of paperboard; Staining on Evaluated at 36
days paperboard under the sample Coating Formula #2A, 2B, 2C Good -
No outside staining; Heavy staining Piled test Stored at 140 F. on
fiber side of paperboard Evaluated at 14 days
[0106]
12TABLE 13 Masking of Packaging Materials Contacted with Gravy Mix,
Pancake Mix and Biscuit Mix Biscuit Mix Pancake Mix II Gravy Mix
(.about.3% Fat (.gtoreq.3% Fat Substrate (.about.10% Fat Content)
Content) Content) Coating Formula #7-4B Good - No outside Pile Test
Stored at 120 F. staining, Light inside Evaluated at 117 days
staining Low density Good- No staining or edge Polyethylene
Extruded wicking; CCNB Paperboard (1/2 Very slight staining seen
mil inside) after 4 months, however, (comparative) print graphics
would likely Filled Carton Test cover the stain; Stored at 120 F.
Staining at die cut edges Evaluated at 154 days and along bottom
fold is worsening in the 5.sup.th month of storage CCNB
(comparative) Good - No Filled Carton Test staining or Stored at
120 F. edge wicking Evaluated at 154 days CCNB (comparative) Poor-
Major staining Good - No Good - No Pile Test staining or staining
or Stored At 120 Deg F. edge wicking edge wicking Evaluated at 24
days Low density Good - No staining Good - No Good - No
Polyethylene Extruded staining staining CCNB Paperboard (1/2 mil
inside) (comparative) Pile Test Stored at 120 F. Evaluated at 28
days PM (comparative) Good - No staining to the Good - No Good - No
Pile Test print side staining staining Stored at 120 F. Evaluated
at 28 days
[0107]
13TABLE 14 Masking of Packaging Materials Contacted with Snack
Crackers and Dog Biscuits Snack Crackers (.about.16% Fat Dog
Biscuits Substrate content) (.about.6% fat Content) Coating Formula
1 Good - No outside Hand filled carton Test without inner liner
staining, no inside Stored at 120 deg F. staining Evaluated at 22
days Coating Formula 1 Good - No Hand filled carton Test without
inner liner outside staining, Stored at 120 deg F. very slight
Evaluated at 72 days staining to corrugated at corners of carton
Coating Formula 1 Good - No Hand filled carton Test without inner
liner outside staining, Stored at 140 deg F. very slight Evaluated
at 72 days staining to corrugated at corners of carton Coating
Formula 1 Good - No Hand filled carton Test without inner liner
outside staining, Stored at TAPPI conditions (73 deg. F., 50% no
staining to humidity) corrugated under Evaluated at 72 days carton
RF2 without inner liner (comparative) Good - No Stored at 120 F.
outside staining, Evaluated at 72 days medium staining to
corrugated at corners of carton RF2 (comparative) Good - No Stored
at 140 F. outside staining, Evaluated at 72 days medium staining to
corrugated at corners of carton RF2 (comparative) Good - No TAPPI
conditions (73 deg. F., 50% humidity) outside staining, Evaluated
at 72 days no staining to corrugated under carton Coating Formula
#2A, 2B, 2C Good - No Pile Test Staining Stored at 140 deg. F. at
14 days
[0108]
14TABLE 15 Masking of Packaging Materials Contacted with Various
Dryer Sheets* Dryer Dryer Sheet Dryer Sheet Substrate Sheet I II
Dryer Sheet III IV Coating Formula 1 Good - Good - No Good - No
Good - No Hand-filled Carton test No outside outside staining
outside Stored at 120 F. outside staining staining Evaluated at 4
days staining Coating Formula 1 Good - Good - No Good - No Good -
No Hand-filled Carton test No outside outside staining outside
Stored at 100 F./70% outside staining staining RH staining
Evaluated at 4 days Coating Formula 1 Good - Good - No Good - No
Good - No Hand-filled Carton test No outside outside staining
outside 80 deg F./80% RH outside staining staining Evaluated at 4
days staining Coating Formula 1 Good - Good - No Good - No Good -
No Hand-filled Carton test No outside outside staining outside
Stored at TAPPI outside staining staining conditions (73 deg. F.,
staining 50% humidity) Evaluated at 4 days Low density Good - Poor
- Major Marginal - Good - No Polyethylene Extruded No outside
Slight outside outside (1/2 mil inside) CCNB outside staining
staining around staining Paperboard staining around die cut
perforations (comparative) perforations Hand-filled carton test
Stored at 120 F. Evaluated at 4 days Low density Good - Good - No
Good - No Good - No Polyethylene Extruded No outside outside
staining outside (1/2 mil inside) CCNB outside staining staining
Paperboard staining (comparative) Hand-filled carton test Stored at
100 F./70% RH Evaluated at 4 days Low density Good - Good - No Good
- No Good - No Polyethylene Extruded No outside outside staining
outside (1/2 mil inside) CCNB outside staining staining Paperboard
staining (comparative) Hand-filled carton test Stored at 80 deg F./
80% RH Evaluated at 4 days Low density Good - Good - No Good - No
Good - No Polyethylene Extruded No outside outside staining outside
(1/2 mil inside) CCNB outside staining staining Paperboard staining
(comparative) Hand-filled carton test Stored at TAPPI conditions
(73 deg. F., 50% humidity) Evaluated at 4 days Coating Formula 1
Good - Poor - Heavy Good - No Good - No Stack test - Stored at No
tack on print staining to print staining to 120 F. staining to
print stack side; slight tack print side; Evaluated at 7 days to
print test* on print to print slight tack on side; slight stack
test print to print tack on print stack test to print stack test
*Composition of dryer sheets unknown. However, commercial dryer
sheets are known to be impregnated with fabric softener
compositions. Such compositions are known to include one or more of
fatty alcohols, mineral oils, or organosilicone materials.
[0109] As set forth in the various Tables above, the substrates
treated according to the methods and compositions and methods of
the present invention effectively mask staining from grease, fat or
oil permeation through a packaging material. Further, the
appearance of the packaging material is equal to or better than
packaging materials treated according to prior art methods and
compositions including the now unavailable flurochemical barrier
treatments. Accordingly, these results demonstrate that the methods
and compositions of the present invention provide a useful and
valuable improvement to the field of packaging materials.
[0110] Throughout this application, various publications are
referenced. The disclosures of these publications in their
entireties are hereby incorporated by reference into this
application in order to more fully describe the state of the art to
which this invention pertains.
[0111] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the scope or spirit of the invention. Other
embodiments of the invention will be apparent to those skilled in
the art from consideration of the specification and practice of the
invention disclosed herein. It is intended that the specification
and examples be considered as exemplary only, with a true scope and
spirit of the invention being indicated by the following
claims.
* * * * *