U.S. patent application number 15/636755 was filed with the patent office on 2017-11-16 for polymer film graphics.
The applicant listed for this patent is Avery Dennison Corporation. Invention is credited to James Bodwell, Michael W. Roughton, David WELCH.
Application Number | 20170327716 15/636755 |
Document ID | / |
Family ID | 38535575 |
Filed Date | 2017-11-16 |
United States Patent
Application |
20170327716 |
Kind Code |
A1 |
Bodwell; James ; et
al. |
November 16, 2017 |
POLYMER FILM GRAPHICS
Abstract
The invention relates to a process for the manufacture of
polymer film graphics comprising providing a continuous substrate
having a release layer thereon; applying an image layer in the
shape of a graphic letter or design to the release layer;
depositing an adhesive layer to the image layer and which has the
same shape as the image layer graphic letter or design; curing the
adhesive and image layers; and winding the polymer film graphics
onto rolls. The invention further relates to a polymer film graphic
comprising a substrate having an upper surface and a lower surface;
a release layer overlying the upper surface of the substrate; an
image layer in the shape of a graphic letter or design overlying
the release layer; an adhesive layer overlying the image layer, the
adhesive layer having the same shape as the image layer graphic
letter or design.
Inventors: |
Bodwell; James; (Concord,
OH) ; Roughton; Michael W.; (South Plainfield,
NJ) ; WELCH; David; (Somerset, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Avery Dennison Corporation |
Glendale |
CA |
US |
|
|
Family ID: |
38535575 |
Appl. No.: |
15/636755 |
Filed: |
June 29, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11689617 |
Mar 22, 2007 |
9725624 |
|
|
15636755 |
|
|
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|
60788386 |
Mar 31, 2006 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 29/06 20130101;
B32B 27/10 20130101; B32B 7/12 20130101; B32B 27/304 20130101; B32B
27/18 20130101; B32B 2307/75 20130101; C09J 2433/00 20130101; B32B
2307/4023 20130101; B32B 2255/12 20130101; B32B 7/06 20130101; B32B
27/08 20130101; B32B 3/10 20130101; B32B 27/00 20130101; B41M 7/009
20130101; B41M 7/0081 20130101; C09J 7/29 20180101; Y10T 428/2486
20150115; B32B 27/22 20130101; B44C 1/162 20130101; B32B 2255/26
20130101; Y10T 428/14 20150115; C09J 2301/204 20200801 |
International
Class: |
C09J 7/02 20060101
C09J007/02; B32B 3/10 20060101 B32B003/10; B32B 7/06 20060101
B32B007/06; B32B 7/12 20060101 B32B007/12; B32B 27/00 20060101
B32B027/00; B32B 27/10 20060101 B32B027/10; B32B 27/18 20060101
B32B027/18; B41M 7/00 20060101 B41M007/00; B44C 1/16 20060101
B44C001/16; B32B 29/06 20060101 B32B029/06; B32B 27/30 20060101
B32B027/30; B32B 27/22 20060101 B32B027/22; B41M 7/00 20060101
B41M007/00; B32B 27/08 20060101 B32B027/08 |
Claims
1. A polymer film graphic comprising: a substrate having an upper
surface and a lower surface; a release layer overlying the upper
surface of the substrate; an image layer in the shape of a graphic
letter or design overlying the release layer; and an adhesive layer
overlying the image layer, wherein the adhesive layer has the same
shape as the image layer graphic letter or design.
2. The polymer film graphic of claim 1, wherein the substrate
comprises a paper, a polymer film, or a combination thereof.
3. The polymer film graphic of claim 1, wherein the substrate
comprises a transparent polymer film.
4. The polymer film graphic of claim 1, wherein the release layer
is disposed between the substrate and the image layer.
5. The polymer film graphic of claim 1, wherein the release layer
comprises a silicone release composition.
6. The polymer film graphic of claim 1, wherein the substrate has a
second release layer on the lower surface of the substrate.
7. The polymer film graphic of claim 1, wherein the adhesive
comprises a pressure sensitive adhesive.
8. The polymer film graphic of claim 1, wherein the adhesive
comprises an acrylic adhesive.
9. The polymer film graphic of claim 1, wherein the adhesive
comprises a hot melt adhesive.
10. The polymer film graphic of claim 1, wherein the image layer
comprises one or more of a plastisol, an organosol, a polyethylene,
a polypropylene, an acrylic, and an epoxy.
11. The polymer film graphic of claim 1, wherein the image layer
comprises a plastisol.
12. The polymer film graphic of claim 1, wherein the image layer
comprises a polyvinyl chloride resin and a plasticizer.
13. The polymer film graphic of claim 1, wherein the image layer
comprises a solvent based ink.
14. The polymer film graphic of claim 1 further comprising: a
carrier layer overlying the upper surface of the adhesive
layer.
15. The polymer film graphic of claim 1 further comprising: a
second adhesive layer disposed between the image layer and the
substrate.
16. The polymer film graphic of claim 15, wherein the second
adhesive layer comprises a pressure sensitive adhesive.
17. The polymer film graphic of claim 15, wherein the second
adhesive layer comprises an acrylic adhesive.
18. The polymer film graphic of claim 15, wherein the second
adhesive layer comprises a hot melt adhesive.
19. A polymer film graphic comprising: a substrate having an upper
surface and a lower surface; an adhesive layer in the shape of a
graphic letter or design overlying the upper surface of the
substrate; an image layer in the shape of a graphic letter or
design overlying the adhesive layer.
20. The polymer film graphic of claim 19, wherein the substrate
comprises a paper, a polymer film, or a combination thereof.
21. The polymer film graphic of claim 19, wherein the substrate
comprises a transparent polymer film.
22. The polymer film graphic of claim 19, wherein the adhesive
comprises a pressure sensitive adhesive.
23. The polymer film graphic of claim 19, wherein the adhesive
comprises an acrylic adhesive.
24. The polymer film graphic of claim 19, wherein the adhesive
comprises a hot melt adhesive.
25. The polymer film graphic of claim 19, wherein the image layer
comprises one or more of a plastisol, an organosol, a polyethylene,
a polypropylene, an acrylic, and an epoxy.
26. The polymer film graphic of claim 19, wherein the image layer
comprises a plastisol.
27. The polymer film graphic of claim 19, wherein the image layer
comprises a polyvinyl chloride resin and a plasticizer.
28. The polymer film graphic of claim 19, wherein the image layer
comprises a solvent based ink.
Description
RELATED APPLICATIONS
[0001] This application is a divisional application and claims
priority upon U.S. application Ser. No. 11/689,617 filed Mar. 22,
2007, now issued as US Patent No. which claims priority to U.S.
Provisional Application No. 60/788,386, filed Mar. 31, 2006. The
entire disclosure of the provisional application is hereby
incorporated by reference.
TECHNICAL FIELD OF THE INVENTION
[0002] The invention relates to a process for manufacturing polymer
film graphics, useful as lettering and free form designs, and
formation of the graphics without the necessity for cutting the
graphics from the polymer film. The invention also relates to the
resulting polymer film graphics.
BACKGROUND OF THE INVENTION
[0003] Graphics cutting methods wherein an image is cut from a
polymer film adhered to a pressure sensitive adhesive composite and
then transferred to a desired substrate are known. This technique
is used to provide a wide variety of graphics applications
including exterior identification signs, lettering and designs, as
well as decorative or commercial graphics on trucks, cars, boats,
and the like. The polymer film that is typically used with these
graphic applications is a calendered or dispersion cast polyvinyl
chloride (PVC) monolayer film. While the use of PVC films have met
with success in the marketplace, such films are often costly to
manufacture and typically result in film waste associated with the
portion of film discarded after cutting of the lettering or design.
This removal step is sometimes referred to in the art as "weeding".
Weeding involves peeling the unneeded portions of a film from the
release liner, leaving only the needed portions representing the
final image adhered to the release liner.
[0004] Therefore, it is desirable to provide a process for
manufacturing a polymer film graphic that eliminates the waste film
associated with wide web coating. It is also desired to provide a
process for forming a polymer film graphic that eliminates the
subsequent cutting of the graphic from application to a
surface.
SUMMARY
[0005] In one embodiment, the invention is directed to a process
for the manufacture of polymer film graphics comprising providing a
continuous substrate having a first and second surface, and having
a first release layer on the first surface; applying an image layer
in the shape of a graphic letter or design to the first release
layer; depositing an adhesive layer onto the image layer, the
adhesive layer having the same shape as the image layer graphic
letter or design; and curing the adhesive and image layers. The
polymer film graphic may be wound into a roll.
[0006] In another embodiment, the invention is directed to a
process for the manufacture of polymer film graphics comprising:
providing a continuous substrate having a first surface and a
second surface and having a first layer of adhesive on the first
surface; printing an image layer in the shape of a graphic letter
or design onto the first layer of adhesive; depositing a second
adhesive layer onto the image layer, the second adhesive layer
having the same shape as the image layer graphic letter or design;
and curing the second adhesive layer and image layer.
[0007] In a further embodiment, the invention is directed to a
polymer film graphic comprising a substrate having an upper surface
and a lower surface; a release layer overlying at least the upper
surface of the substrate; an image layer in the shape of a graphic
letter or design overlying the release layer; and an adhesive layer
overlying the image layer in the same shape as the image layer
graphic letter or design. The polymer film graphic may further
comprise a second release layer on the lower surface of the
substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic illustration of the side view of a
film embodying the present invention in a particular form.
[0009] FIG. 2 is a schematic illustration of the side view of an
alternative embodiment of the present invention.
[0010] FIG. 3 is a schematic illustration of the side view of a
further embodiment of the present invention.
[0011] FIG. 4 is a schematic illustration of the side view of
delivery of the material used to form the image layer for making
the polymer film graphics of the present invention.
[0012] FIG. 5 is diagram of an apparatus for the dispensing process
for making the polymer film graphics of the present invention.
[0013] FIG. 6 is a schematic illustration of an alternative
embodiment wherein the polymer film graphic is prepared on an
adhesive coated substrate.
[0014] FIG. 7 is a schematic illustration of an alternative
embodiment wherein a release liner is laminated to the polymer film
graphic.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0015] The present invention relates to graphic letters and free
form designs formed from a polymer film without the necessity for
cutting of the lettering or design. The term "overlies" and cognate
terms such as "overlying" and the like, when referring to the
relationship of one or a first layer relative to another or a
second layer, refers to the fact that the first layer partially or
completely overlies the second layer. The term "underlies" and
cognate terms such as "underlying" and the like have similar
meanings except that the first layer partially or completely lies
under, rather than over, the second layer.
[0016] The term "transparent" when referring to one or more layers
of the graphic means that the ink or print layer(s) can be seen
through such layer or layers.
[0017] The graphic letters and designs of the present invention are
illustrated in reference to the attached drawings. FIG. 1 is a
schematic illustration of a side view of a graphic 1 produced
according to the present invention. Graphic 1 comprises a substrate
or casting sheet 10 having an upper surface 12 and a lower surface
14. Overlying upper surface 12 of substrate 10 is a first release
layer 20. An image layer 30 in the shape of a graphic letter or
design overlies the first release layer 20 on the substrate 10. An
adhesive layer 40 having upper surface 45 and lower surface 48
overlies the image layer 30 and has the same shape as the graphic
letter or design of image layer 30.
[0018] The image layer is formed on a substrate or casting sheet 10
which may comprise paper, polymer film, or a combination thereof.
Paper substrates are useful because of the wide variety of
applications in which they can be employed. Paper is also
relatively inexpensive and has desirable properties such as
antiblocking, antistatic, dimensional stability, and can
potentially be recycled. Any type of paper having sufficient
tensile strength to be handled in conventional paper coating and
treating apparatus can be employed as the substrate material. Thus,
any type of paper can be used depending upon the end use and
particular personal preferences. Included among the types of paper
which can be used are clay coated paper, glassine, polymer coated
paper, hemp, and similar cellulose material prepared by such
processes as the soda, sulfite or sulfate (Kraft) processes, the
neutral sulfide cooking process, alkali-chlorine processes, nitric
acid processes, semi-chemical processes, etc. Although paper of any
weight can be employed as a substrate material, paper having
weights in the range of from about 30 to about 120 pounds per ream
are useful, and papers having weights in the range of from about 60
to about 100 pounds per ream are presently preferred. The term
"ream" as used herein equals 3000 square feet.
[0019] Alternatively, the substrate 10 may be a polymer film, and
examples of polymer films include polyolefin, polyester, PET, and
the like. The polyolefin films may comprise polymer and copolymers
of monoolefins having from 2 to about 12 carbon atoms, and in one
embodiment from 2 to about 8 carbon atoms, and in one embodiment
from about 2 to about 4 carbon atoms per molecule. Examples of such
homopolymers include polyethylene, polypropylene, poly-1-butene,
etc. The examples of copolymers within the above definition include
copolymers of ethylene with from about 1% to about 10% by weight of
ethylene or 1-butene, etc. Films prepared from blends of copolymers
or blends of copolymers with homopolymers are also useful. The
films may be extruded in mono or multilayers. In one embodiment,
the substrate 10 is a naturally releasing low surface energy film
of polypropylene, polyethylene, polyacrylate or polyacetal polymer
and copolymers, or combinations thereof. The surface energy of
these films will range from about 10 dynes/cm to about 30
dynes/cm.
[0020] Another type of material that can be used as the substrate
10 is a polycoated kraft liner that is basically comprised of a
kraft liner that is coated on either one or both sides with a
polymer coating. The polymer coating, which can be comprised of
high, medium, or low density polyethylene, propylene, polyester,
and other similar polymer films, is coated onto the substrate
surface to add strength and/or dimensional stability to the liner.
The weight of these types of liners ranges from about 30 to about
100 pounds per ream, with about 94 to about 100 pounds per ream
representing a typical range. In total, the final liner is
comprised of between 10% and 40% polymer and from 60% to 90% paper.
For two sided coatings, the quantity of polymer is approximately
evenly divided between the top and bottom surface of the paper.
[0021] In one embodiment, overlying the upper surface 12 of
substrate 10, is release layer 20. The composition of the release
layer 20 can be any release coating composition known in the art.
Silicone release coating compositions are preferred, and any of the
silicone release coating compositions that are known in the art can
be used. The major component of the silicone release coating is a
polyorganosiloxane and more often polydimethylsiloxane. The
silicone release coating compositions used may be room temperature
cured, thermally cured, or radiation cured. Generally, the room
temperature and thermally curable compositions comprise at least
one polyorganosiloxane and at least one catalyst (or curing agent)
for such polyorganosiloxane(s). Such compositions may also contain
at least one cure accelerator and/or adhesivity promoter. As is
known in the art, some materials have the capability of performing
both functions, i.e., the capability of acting as a cure
accelerator to increase the rate, reduce the curing temperature,
etc., and also as an adhesivity promoter to improve bonding of the
silicone composition to the substrate. The use of such dual
function additives where appropriate is within the purview of the
invention.
[0022] The release coating composition is applied to the substrate
10 using known techniques. These include, for example, gravure,
reverse gravure, offset gravure, roller coating, brushing,
knife-over roll, metering rod, reverse roll coating, doctor knife,
dipping, die coating, spraying curtain coating, and the like. In
one embodiment, the thickness or caliper of the resulting release
coating may range from about 0.1 to about 20 mils, and in one
embodiment from about 0.2 to about 0.5 mils.
[0023] In one embodiment, substrate 10 has a first release layer 20
on upper surface 12 and a second release layer on lower surface 14.
Upon rolling or stacking the graphic, the upper surface 45 of
adhesive layer 40 comes into contact with the second release
layer.
[0024] As illustrated in FIG. 2, in one embodiment, the polymer
graphic 1 of the invention may optionally comprise a carrier 50
which is a release-coated liner having one surface (the
release-coated surface) in contact with the otherwise exposed upper
surface 45 of adhesive layer 40 when the graphics 1 are stacked or
otherwise rolled upon themselves. The carrier 50 is used to protect
the upper surface 45 of the adhesive layer 40 during preparation,
handling, storage and shipping of the graphics 1. The carrier 50 is
removed from the graphic 1 prior to positioning and adhering the
graphic 1 to a surface. The release-coated liner 50 may comprise a
substrate sheet of paper, a polymer film or combinations thereof
coated with a release composition. Such materials are as described
with reference to the substrate 10.
[0025] Image layer 30 is formed in the shape of a letter or free
form design and applied over the release layer 20. In one
embodiment, the image layer 30 comprises a plastisol or organosol.
The term plastisol or organosol generally refers to a dispersion of
fine-particle plastic powders or granules in softeners that harden
or gelate when heated to higher temperatures. The plastisol
formulation that is applied to the substrate 10 comprises a resin,
a plasticizer, and optionally an activator/stabilizer, a viscosity
depressant, a pigment, and filler. The plastic powders or granules
are composed of fine particle polymers and copolymers including
vinyl chloride polymers, polyvinyl chloride-vinyl acetate
copolymers, acrylate polymers and copolymers such as polymethyl
methacrylate (PMMA) and polyalkyl methacrylate (PAMA); polyolefins
such as polyethylene, including high density polyethylene, low
density polyethylene, linear low density polyethylene, and linear
ultra low density polyethylene, polypropylene, and polybutylene;
polyesters; polycarbonate; polyacrylonitrile; butadiene-styrene
polymers; polyamide; ethylene vinylacetate copolymer; treated and
untreated poly(ethylene terephthalate); polystyrene; vinyl
copolymers; polyvinyl acetates; olefinic copolymers such as
ethylene/methacrylate copolymers, ethylene/vinyl acetate
copolymers;
[0026] acrylonitrile-butadiene-styrene copolymers;
ethylene/propylene copolymers; acrylic polymers and copolymers;
polyurethanes; and combinations of the foregoing. The vinyl
chloride polymers that may be used are the resinous products
obtained by the polymerization of vinyl chloride in the presence or
absence of another copolymerizable vinyl compound. The term "vinyl
chloride resin" includes vinyl chloride homopolymers as well as
copolymers, such as those formed between vinyl chloride and at
least one 5 other copolymerizable vinyl monomer, such as vinyl
acetate, vinyl propionate, vinyl butyrate, vinylidene chloride,
styrene, methyl-methacrylate, and the like. In one embodiment the
plastisol contains a PVC resin.
[0027] Plasticizers for making poly(vinyl chloride) plastisols are
well known in the art and commercially available. Typical
plasticizers include di(2-ethylehexyl)phthalate,
di(2-ethyl-4-methylpentyl)phthalate, di-capryl phthalate,
di-isodecyl phthalate, di-capryl phthalate, di-isodecyl phthalate,
di(2-ethylhexyl)sebacate, di(2-ethylhexyl)azelate, monomeric
epoxy(2-ethyl-hexylepoxytallate), triethylene glycol dicaprylate,
acetyl tributyl citrate, 2,2,4-trimethylpentane-1,3-diol
diisobutyrate, polyester of neopentyl glycol and 15 adipic acid
(M.W.=1,200-1,300), epoxidized soy bean oil (M.W. approximately
1,000), high boiling (above about 200.degree. C.) liquid mixture of
partially hydrogenated terphenyls and iso-octyl palmitate, dioctyl
phthalate, mixed phthalate esters containing alcohol moieties
having 7 to 11 carbon atoms, diisononyl phthalate, diisooctyl
phthalate, dioctyl terephthalate, mixed phthalate esters based on
isomeric nonyl alcohols, mixed phthalate esters containing alcohol
moieties having 6 to 12 carbon atoms, trioctyl trimellitate, butyl
benzyl phthalate, and polymeric plasticizers such as
poly(2,2,4-trimethyl-1,3-pentanediol adipate)terminated with the
monoisobutyrate acid ester of 2,2,4-trimethyl-1,3-pentanediol, and
poly(2,2-dimethyl-1,3-propanediol adipate) terminated with
2-ethylhexanol and the like. Cost considerations as well as desired
viscosity and adhesion properties of the system affect the specific
plasticizer choice. Where lower viscosity is desired without
further plasticizer, for example, for spray coating application,
small amounts of a diluent (5-15%) such as toluene, xylene, methyl
isoamyl ketone, diisobutyl ketone, methyl ethyl ketone, and the
like may be added to form the sprayable organosol.
[0028] Mixtures of the above identified plasticizers may be used if
desired. Normally, the plasticizer will be present in the plastisol
in the amount of about 20 to about 130 parts per hundred parts
(pph) of vinyl chloride resin. The plasticizers may be incorporated
in the vinyl chloride resin alone with or without other additives,
by a suitable process such as calendering, mixing or kneading of
the ingredients. A desirable procedure involves forming a vinyl
resin dispersion that can be cast in a film or thicker body, and
then heated to form a homogenous body of plasticized resin. Such
dispersions are suspensions of vinyl chloride resin particles in
nonaqueous liquids, including the plasticizer, which do not
dissolve the resin at ordinary temperature but do at elevated
temperatures. If the liquid phase consists of plasticizer only, the
dispersion is often termed as "plastisol", whereas if the
dispersing liquid also contains volatile components that evaporate
upon heating, the dispersion is often termed as "organosol".
Commercially available examples of plastisol/organosol polymer
useful in the present invention include those manufactured by
Polyone and Chemionics.
[0029] In one embodiment, the image layer 30 is formed from a
polymeric material, such as polyethylene, polypropylene, an
acrylic, an epoxy, copolymers and the like. Useful acrylate
polymers and copolymers for forming the liquid material layer 30
include polyacrylate and methacrylate homopolymers or copolymers of
C1-C12 acrylate or methacrylate monomers, such as methyl, ethyl,
propyl, butyl, hexyl, or octyl acrylates or methacrylates.
Commercial examples of available polymers include those produced by
Acronal.RTM. Acrylics from BASF, Rohm and Haas Rhoplex.RTM.,
Plexiglas.RTM., and Lucidene products.
[0030] Epoxy resins useful for making the image layer 30 include
epoxy resins and polymeric epoxy resins. These resins can vary
greatly in the nature of their backbones and substituent groups.
The epoxy resins of the invention can undergo initial curing upon
exposure to UV radiation via a free radical mechanism with the
addition of an appropriate photoinitiator. Final curing of the
epoxy resin layer is accomplished by heating the epoxy resin. A
particularly useful epoxy layer is formed from a mixture of a
diglycidyl ether of bisphenol A, an epoxy diacrylate and an amine
curing agent. Epon.RTM. 825, a bisphenol A epichlorohydrin epoxy
resin commercially available from Shell Chemical Co., is an example
of a diglycidyl ether of bisphenol A. An epoxy diacrylate useful in
the present invention is Ebecryl.RTM. 3700, a bisphenol A epoxy
diacrylate commercially available from UCB Chemical Corp.
[0031] In one embodiment, the image layer 30 is formed from a
polymer that can be dispersed or dissolved in solvents or water, as
are known in the art. Such polymers include, but are not limited to
polycarbonate, polyacrylonitrile, butadiene-styrene polymers,
poly(methylmethacrylate), polyamide, ethylene vinylacetate
copolymer, treated and untreated poly(ethylene terephthalate),
polystyrene, polyolefins, such as polyethylene, including high
density polyethylene, low density polyethylene, linear low density
polyethylene, and linear ultra low density polyethylene,
polypropylene, and polybutylenes; vinyl copolymers, and polyvinyl
acetates, olefinic copolymers, such as ethylene/methacrylate
copolymers, ethylene/vinyl acetate copolymers,
acrylonitrile-butadiene-styrene copolymers, and ethylene/propylene
copolymers; acrylic polymers and copolymers; polyurethanes; and
mixtures thereof.
[0032] The image layer 30 can be pigmented or can be transparent.
In one embodiment, the image layer 30 is pigmented. The pigment can
be a metallic pigment, heavy metal-based pigment, a heavy-metal
free pigment, or an organic pigment. A heavy metal is defined
herein as being lead, cadmium, chromium, or antimony. The pigments
that can be used include titanium dioxide, both rutile and anatase
crystal structure. The titanium dioxide may be coated or uncoated
(e.g. aluminum oxide coated TiO.sub.2).
[0033] In one embodiment, pigment is added to image layer 30 in the
form of a concentrate containing the pigment and a resin carrier.
The concentrate may contain, for example from about 20% to about
80% by weight pigment, and about 20% to about 80% by weight resin
carrier. The resin carrier can be 25 any thermoplastic polymer
having a glass transition temperature, in one embodiment, from
about -70.degree. C. up to about 150.degree. C. and in one
embodiment, from about 100.degree. C. to about 175.degree. C. The
carriers resins include polyolefin, thermoplastic polymers of
ethylene and propylene, a polyester, a polycarbonate, a styrene
derived polymer, a polyurethane, a polyacryl, a polymethacryl, a
polyvinyl alcohol, a polyamide, a polyimide, a polysulfone, a
polymethylpentene, a polyacetyl, a vinyl halide derived polymer, a
poly(ethylene vinyl alcohol), a vinyl acetate derived polymer, an
ionomer, and mixtures thereof. In one embodiment, a titanium
dioxide concentrate is used which is comprised of a blend of about
30% to about 70% by weight polypropylene and about 70% to about 30%
by weight titanium dioxide. An example of a commercially available
pigment concentrate that can be used is available from A. Schulman
under the tradename Polybatch White P8555 SD, which is identified
as a white color concentrate of 50% by weight in a polypropylene
homopolymer carrier resin. Examples of other pigment concentrates
include, but are not limited to Ampacet 150380, identified as a red
pigment concentrate, Ampacet 190303, identified as a black pigment
concentrate; Ampacet LR-87132 Orange PE MB, identified as a lead
molybdate concentrate, all available from Ampacet Corporation. The
heavy metal-free pigment concentrates that can be used include
Ampacet LR-86813 Yellow UV PE MB, Ampacet LR-86810 Red PE MB,
Ampacet LR-86816 Orange PE MB, and Ampacet LR-86789 Red UV PE MB.
The concentration of the pigment in the liquid film material can be
up to about 25% by weight, and in one embodiment about 5% to about
25% by weight, and in one embodiment about 10% to about 20% by
weight.
[0034] In one embodiment, color can be imparted to the image layer
30 by use of a dye-based ink. The inks used include commercially
available water-based, solvent-based or radiation curable inks.
Examples of such inks include Sun Sheet (a product of Sun Chemical
identified as an alcohol dilutable polyamide ink), Suntex MP (a
product of Sun Chemical identified as a solvent-based ink), X-Cel
(a product of Water Ink Technologies identified as a water-based
film ink), Uvilith AR-109 Rubine Red (a product of Daw Ink
identified as a UV ink) and CLA91598F (a product of Sun Chemical
identified as a multibond black solvent-based ink).
[0035] In one embodiment, the image layer 30 is produced from
printed ink. Suitable inks include the Color+series of solvent
based inks commercially available from Fujifilm Sericol USA, Inc.
of Kansas City, Kans. The ink can be applied through the use of
digital format printers such as the Indigo.RTM. printers available
from Hewitt Packard or Palo Alto, Calif., or wide format printers
such as those available from Mimaki Engineering Company of Japan
under the trade name Mimaki.
[0036] In one embodiment, pigment is added to adhesive layer 40.
When pigmented, the adhesive layer 40 can contain one or more of
the pigments described above. The pressure sensitive adhesive layer
40 can be any pressure sensitive adhesive known in the art. These
include rubber based adhesives, acrylic adhesives, vinyl ether
adhesives, silicone adhesives, and mixtures of two or more thereof.
Included are the pressure sensitive adhesive materials described in
"Adhesion and Bonding," Encyclopedia of Polymer Science and
Engineering, Vol. 1, pages 476-546, Interscience Publishers 2nd Ed.
1985, the disclosure of which is hereby incorporated by reference.
The pressure sensitive adhesive materials that are useful may
contain as a major constituent an adhesive polymer such as acrylic
type polymers, block copolymers, natural, reclaimed or styrene
butadiene rubbers, tackified nature or synthetic rubbers, random
copolymers of ethylene and vinyl acetate, ethylene-vinyl-acrylic
terpolymers, polyisobutylene, poly(vinyl ether), etc. The pressure
sensitive adhesive materials are typically characterized by glass
transition temperatures in the range of about -70.degree. C. to
about 10.degree. C.
[0037] Other materials in addition to the foregoing resins may be
included in the pressure sensitive adhesive layer 40. These include
solid tackifying resins, liquid tackifiers (often referred to as
plasticizers), antioxidants, fillers, pigments, waxes, etc. The
adhesive materials may contain a blend of solid tackifyng resins
and liquid tackifying resins (or liquid plasticizers).
[0038] The layer 40 of pressure sensitive adhesive generally has a
thickness of about 0.2 to about 2.5 mils, and in one embodiment
about 0.5 to about 1.5 mils. In one embodiment, the coat weight of
the pressure sensitive adhesive is in the range of about 10 to
about 50 grams per square meter (gsm), and in one embodiment about
20 to about 35 gsm.
[0039] The image layer 30 also may include additives other than
plasticizers that are normally incorporated in vinyl resin
compositions. Generally such compositions include one or more
stabilizers to impart resistance to thermal degradation. Inorganic
fillers, either fibrous or non-fibrous, may be used where
desirable. In addition, other additives, such as solvents,
diluents, binders and the like may be employed. The image layer 30
also may include other materials such as antioxidants, light
stabilizers such as (UV) light absorbers and/or other light
stabilizers, viscosity modifiers, antiblock and/or slip additives,
reinforcing agents, processing acids, mineral oil, and the like. In
one embodiment, stabilizers in addition to those normally present
in PVC plastisol formulations may be included. Examples of such
stabilizers include ultraviolet light stabilizers including
hindered amine light stabilizers. The hindered amine light
stabilizers may, for example, be derivatives of 2,2,6,6-tetraalkyl
piperidines or substituted piperizinediones. A number of hindered
amine light stabilizers useful in the invention are available
commercially such 5 as from Ciba-Geigy Corporation under the
general trade designation "Tinuvin" and "Chemissorb", and from
Cytec under the general designation "Cyasorb-UV". Examples include
Tinuvin 783 which is identified as a mixture of poly
[[60[1,1,3,3-tetramethyl
butyl)amino]-1,3,5-trizine-2,4-diyl][[2,2,6,6-tetramethyl-4-piperidyl)imi-
no]hexamethylene[2,2,6,6-tetramethyl-4- piperidyl imino]] and
dimethyl succinate polymer with
4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; Tinuvin 770
which is identified as
bis-(2,2,6,6-tetramethyl-4-piperidinyl)-sebacate; Tinuvin 765 which
is identified as
bis-(1,2,2,6,6-pentamethyl-4-piperidinyl)-sebacate; Tinuvin 622
which is a polyester of succinic acid and N-beta-hydroxy
ethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidine; and Chemissorb 944
which is
poly[6-(1,1,3,3-tetramethylbutyl)amino]-s-triazine-2,4-diy[[2,2,6,6-te-
tramethyl-4-piperidyl) imino]hexamethylene
(2,2,6,6-tetramethyl-4-piperidyl)imino]. A useful stabilizer is
available under the tradename Ampacet 10561 which is a product of
Ampacet identified as a UV stabilizer concentrate containing 20% by
weight of a UV stabilizer and 80% by weight of a low density
polyethylene carrier resin; the UV stabilizer in this product is
Chemissorb 944. Useful light stabilizers are also provided in
Ampacet 150380 and Ampacet 190303, both of which are pigment
concentrates discussed above. Ampacet 150380 has a UV stabilizer
concentration of 7.5% by weight. Ampacet 190303 has a UV stabilizer
concentration of 4% by weight. The UV stabilizer in each of these
products is Chemissorb 944. Ampacet LR-89933 is a grey concentrate
having a UV stabilizer concentration of 4.5% by weight, the UV
stabilizer being Tinuvin 783. Heat stabilizers include epoxies such
as Thermcheck 909, and barium/zinc heat stabilizers such as Mark
121 from Crompton Industries.
[0040] The image layer 30 may contain antiblock and/or slip
additives. The antiblock additives include natural silica,
diatomaceous earth, synthetic silica, glass spheres, ceramic
particles, etc. The slip additives include primary amides such as
stearamide, behenamide, oleamide, erucamide, and the like;
secondary amides such as stearyl erucamide, erucyl erucamide, oleyl
palimitamide, stearyl stearamide, erucyl stearamide, and the like;
ethylene bisamides such as N,N'-ethylenebisstearamide,
N,N'-ethylenebisolamide and the like; and combinations of any two
or more of the foregoing amides. An example of a useful slip
additive is available from Ampacet under the trade designation
10061; this product is identified as a concentrate containing 6% by
weight of a stearamide slip additive. The antiblock and slip
additives may be added together in the form of a resin concentrate.
An example of such a concentrate is available from DuPont under the
tradename Elvax CE9619-1. This resin concentrate contains 20% by
weight silica, 7% by weight of an amide slip additive, and 73% by
weight of Elvax 3170 (a product of DuPont identified as an
ethylene/vinyl acetate copolymer having a vinyl acetate content of
18% by weight). The antiblock additive can be used at a
concentration in the range of up to about 1% by weight, and in one
embodiment about 0.01% to about 0.5% by weight. The slip additive
can be used at a concentration in the range of up to about 1% by
weight, and in one embodiment about 0.01% to about 0.5% by
weight.
[0041] Referring to FIG. 4, there is depicted in cross section of
one embodiment of a process for delivery of the material used to
produce the image layer 30 to the substrate 10. Dispensing heads
50a, 50b, 50c, are attached to a dispensing head rail 60. In one
embodiment, dispensing heads 50a, 50b, 50c are digitally driven by
computer (not shown) to dispense layer 30 in letter or design form
as desired. In one embodiment, the motion of the substrate 10 past
the dispensing heads 50a, 50b, 50c is digitally driven by computer
(not shown). The material of image layer 30 is dispensed onto
substrate 10 having release layer 20. In one embodiment, the
material of image layer 30 is dispensed by spraying. In one
embodiment, the material of image layer 30 is dispensed by powder
coating. The thickness of the layer dispensed depends upon the
application for which it is intended and will be, in one
embodiment, from about 0.001 mil to about 15 mils, and in one
embodiment, from about 1.0 mils to about 5 mils. The thickness of
the film 30 dispensed will be controlled by the speed of the
applicator roll as well as the gap between the dispensing heads
50a, 50b, 50c and the applicator roll and pressure applied to the
spray nozzle.
[0042] A representation of one embodiment of the inventive process
is shown in FIG. 5, in which an applicator roll carries the
substrate 10 coated with release layer 20. Substrate 10 proceeds
past dispensing heads 50a, 50b, 50c disposed over substrate 10 on
dispensing head rail 60 and dispense material to produce image
layer 30 in a desired letter or design onto substrate 10. In one
embodiment, substrate 10 proceeds past a second set of dispensing
heads (not shown), from which is dispensed adhesive layer 40 onto
image layer 30 so as to conform with adhesive layer 40 graphic.
Substrate 10 with dispensed image layer 30 and adhesive 40 layers
are then thermally cured or radiation cured. In one embodiment,
following application of the image layer 30 to substrate 10,
substrate 10 will then proceed to curing prior to application of
adhesive layer 40.
[0043] In one embodiment, as illustrated in FIG. 3, upper surface
12 of substrate 10 is coated with adhesive layer 40 in the shape of
a desired letter or design. The material used to produce image
layer 30 is then dispensed over adhesive layer 40 so as to conform
to and have the same shape as adhesive layer 40 letter or
design.
[0044] Curing of the image layer 30 and adhesive 40 layers can be
effected in a continuous manner by passing the coated substrate
through equipment that is designed to provide the layers 30, 40
with sufficient residence time to completely cure the layers 30,
40. Curing may be effected at or near atmospheric pressure, in one
embodiment, in an inert atmosphere such as nitrogen or argon. The
length of exposure necessary to cure the layers 30, 40 varies with
such factors as the particular formulation used, the type and
wavelength of radiation, dosage rate, the atmosphere, energy flux,
concentration of photoinitiator (when required), and the thickness
of the layers 30, 40. Generally, the exposure is quite brief and
curing is completed in less than about 1 minute. The actual
exposure time required to give proper curing for various coatings
can be readily determined by one skilled in the art with a minimum
of experimentation. Where thermal curing is utilized, oven
temperatures will range from about 230.degree. F. to about
420.degree. F.
[0045] In one embodiment illustrated in FIGS. 6 and 7, the process
for producing the graphic includes printing an ink layer or pattern
30 in the desired shape over or laminated to an adhesive layer 60
that is adhered to a paper or polymeric substrate 10. The printing
is accomplished by laying down or creating an ink film 30, such as
by using a digital printer 64. The ink is permitted time to cure,
such as by the application of ultraviolet energy, and/or allowing
the solvent to evaporate prior to applying a second adhesive layer
62 to the surface of the ink. A release liner may be applied to the
second adhesive layer 62 by a laminating roll as illustrated in
FIG. 7.
[0046] The image layer 30 may be prepared in reverse image format,
particularly if a clear or transparent substrate 10 is used.
Alternatively, the image is printed or prepared such that the image
is visible in normal sight configurations, depending on the design
and layout of the product. Once the material used to form the image
layer exits the printer, it is then applied to or laminated to the
adhesive layer.
[0047] A clear ink or an ink that becomes clear upon curing may be
applied over the image layer or as part of the image layer, which
may eliminate the need for adding a clear protective film layer
over the top of the image layer. Alternatively, a clear ink layer
can be used to complement the protective layer, such as by creating
screening or shading.
[0048] While the invention has been explained in relation to its
preferred embodiments, it is to be understood that various
modifications thereof will become apparent to those skilled in the
art upon reading the specification. Therefore it is to be
understood that the invention disclosed herein is intended to cover
such modifications as fall within the scope of the appended
claims.
* * * * *