U.S. patent application number 11/638196 was filed with the patent office on 2007-05-03 for multi-layer dry paint decorative laminate having discoloration prevention barrier.
This patent application is currently assigned to AVERY DENNISON CORPORATION. Invention is credited to Roger A. Fahlsing, Valery Boris Golub, Keith L. Truog.
Application Number | 20070098943 11/638196 |
Document ID | / |
Family ID | 32911919 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070098943 |
Kind Code |
A1 |
Truog; Keith L. ; et
al. |
May 3, 2007 |
Multi-layer dry paint decorative laminate having discoloration
prevention barrier
Abstract
A decorative dry paint transfer laminate includes a layer of dry
paint, a pressure-sensitive adhesive layer on one side of the dry
paint layer, and a release liner in releasable contact with the dry
paint layer on a side opposite from the pressure-sensitive adhesive
(PSA). The release liner has a matte release coat layer that
contacts the dry paint layer. The release liner is released from
the dry paint layer after the PSA side is attached to a surface.
The matte release coat adheres to the dry paint layer to provide a
protective function but also to transfer a decorative matte finish
to the dry paint layer when the release liner is removed from it.
The laminate includes a barrier layer to protect against
significant discoloration of the color in the dry paint layer
caused by migration of mono azo pigments from a painted
surface.
Inventors: |
Truog; Keith L.; (Crown
Point, IN) ; Fahlsing; Roger A.; (Hobart, IN)
; Golub; Valery Boris; (Highland, IN) |
Correspondence
Address: |
CHRISTIE, PARKER & HALE, LLP
PO BOX 7068
PASADENA
CA
91109-7068
US
|
Assignee: |
AVERY DENNISON CORPORATION
|
Family ID: |
32911919 |
Appl. No.: |
11/638196 |
Filed: |
December 12, 2006 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10779528 |
Feb 13, 2004 |
|
|
|
11638196 |
Dec 12, 2006 |
|
|
|
10457826 |
Jun 9, 2003 |
7132142 |
|
|
10779528 |
Feb 13, 2004 |
|
|
|
10367611 |
Feb 14, 2003 |
|
|
|
10457826 |
Jun 9, 2003 |
|
|
|
Current U.S.
Class: |
428/40.1 ;
428/354 |
Current CPC
Class: |
C09J 7/22 20180101; B32B
27/20 20130101; B32B 27/32 20130101; B32B 27/36 20130101; B32B
27/34 20130101; B32B 2264/105 20130101; Y10T 428/24802 20150115;
B32B 5/022 20130101; B32B 37/153 20130101; B32B 2255/10 20130101;
B32B 2307/546 20130101; B32B 2307/704 20130101; B32B 2451/00
20130101; B32B 27/308 20130101; B32B 2307/4026 20130101; B32B
2307/42 20130101; B32B 2307/7242 20130101; B44C 1/105 20130101;
C09J 7/38 20180101; C09J 7/385 20180101; B32B 2262/062 20130101;
C09J 7/29 20180101; Y10S 428/906 20130101; B32B 7/02 20130101; Y10T
428/1462 20150115; Y10T 428/24372 20150115; B32B 27/30 20130101;
B32B 7/12 20130101; Y10T 428/1467 20150115; B32B 7/06 20130101;
B44C 1/1741 20130101; B32B 27/306 20130101; C09J 2301/302 20200801;
B32B 2270/00 20130101; B32B 2264/10 20130101; B44F 1/02 20130101;
Y10T 428/1486 20150115; B32B 2607/02 20130101; Y10T 428/14
20150115; Y10T 428/24355 20150115; B32B 2264/102 20130101; B32B
27/12 20130101; B44C 1/17 20130101; B32B 2255/20 20130101; Y10T
428/2848 20150115; Y10T 428/31786 20150401; B32B 27/08 20130101;
B32B 2262/02 20130101; B32B 2307/7265 20130101; C09J 7/403
20180101; C09J 2433/00 20130101 |
Class at
Publication: |
428/040.1 ;
428/354 |
International
Class: |
B32B 33/00 20060101
B32B033/00; B32B 7/12 20060101 B32B007/12 |
Claims
1. A multi-layer decorative laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry) paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner
removable from the dry paint layer at room temperature for exposing
an outer surface of the dry paint layer when the pressure-sensitive
adhesive layer adheres the laminate to the substrate surface under
application of pressure and the release liner is peeled away from
the dry paint layer; and a barrier layer formed as a thin, flexible
barrier film disposed between the adhesive layer and the color
layer, the barrier layer film positioned between the adhesive layer
and the color layer and made from a material so as to inhibit
migration of discoloration-causing pigments from a painted surface
of the substrate through the adhesive layer to the color layer
sufficiently to essentially prevent noticeable color change caused
by the migrating pigments from occurring in the color layer under
room temperature conditions, in which the barrier layer material is
selected from the group consisting of an acrylic resinous material
which has been cross-linked to an amount sufficient to reduce
pigment transmission to the color layer, a polymeric material
containing an adhesion promoter, a high molecular weight acrylic
resinous material having a molecular weight in excess of 250,000,
or a polymeric material containing a fine particulate dispersed
barrier filler material that reduces pigment transmission to the
color layer, the barrier filler material comprising a metal oxide,
a metal compound and/or a metal salt.
2. The article according to claim 1 in which the barrier layer is
applied at a dry film thickness in the range of about 0.05 to about
0.20 mil.
3. The article according to claim 1 in which the barrier layer has
a glass transition temperature (Tg) greater than about 60.degree.
C.
4. The article according to claim 1 in which the barrier material
has a dry film thickness of not more than about 10% of the total
thickness of the decorative laminate (exclusive of the release
liner).
5. The article according to claim 1 in which the laminate further
includes a tie coat for enhancing adhesion between the cross-linked
barrier layer and the pressure-sensitive adhesive layer.
6. The article according to claim 1 in which the pressure-sensitive
adhesive comprises a cross-linked acrylic resinous material.
7. The article according to claim 1 in which the pressure-sensitive
adhesive comprises an internally cross-linked acrylic emulsion.
8. The article according to claim 1 in which the release liner
comprising a matte release coat comprising a cross-linked resinous
material bonded to the release liner and having a micro-roughened
surface that transfers a matte surface finish to the dry paint
layer.
9. The article according to claim 8 in which the dry paint layer
comprises a pigmented color coat layer and a transparent outer
clear coat layer bonded to the color coat and in contact with the
release liner.
10. The article according to claim 9 in which the transparent outer
clear coat layer comprises an acrylic resinous material.
11. The article according to claim 10 in which the
pressure-sensitive adhesive layer comprises a cross-linked acrylic
resinous material.
12. The article according to claim 1 in which the barrier layer
material produces a color shift of less than about 0.30 .DELTA.b*
C.I.E. color scale shift units at 60.degree. C.
13. A multi-layer decorative laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner
removable from the dry paint layer at room temperature for exposing
an outer surface of the dry paint layer when the pressure-sensitive
adhesive layer adheres the laminate to the substrate surface under
application of pressure and the release liner is peeled away from
the dry paint layer; and a barrier layer formed as a thin, flexible
barrier film disposed between the adhesive layer and the color
layer, the barrier layer film positioned between the adhesive layer
and the color layer and made from a material having a glass
transition temperature greater than about 60.degree. C. so as to
inhibit migration of discoloration-causing pigments from a painted
surface of the substrate through the adhesive layer to the color
layer, in which the barrier material has a dry film thickness of
not more than about 10% of the total thickness of the decorative
laminate (exclusive of the release liner).
14. The article according to claim 13 in which the barrier layer is
applied at a dry film thickness in the range of about 0.05 to about
0.20 mil.
15. The article according to claim 13 in which the barrier layer
comprises an acrylic resinous material which has been cross-linked
to an amount sufficient to reduce the pigment transmission to the
color layer.
16. The article according to claim 13 in which the barrier layer
material includes an adhesion promoter.
17. The article according to claim 13 in which the laminate further
includes a tie coat for enhancing adhesion between the cross-linked
barrier layer and the pressure-sensitive adhesive layer.
18. The article according to claim 13 in which the barrier layer
material comprises a high molecular weight acrylic resinous
material having a molecular weight in excess of 250,000.
19. The article according to claim 13 in which the barrier layer
material contains a fine particulate dispersed filler material that
reduces the pigment transmission to the color layer.
20. The article according to claim 19 in which the barrier filler
material comprises a metal oxide, a metal compound and/or a melt
salt.
21. The article according to claim 13 in which the
pressure-sensitive adhesive comprises a cross-linked acrylic
resinous material.
22. The article according to claim 13 in which the barrier layer
material produces a color shift of less than about 0.30 .DELTA.b*
C.I.E. color scale shift units at 60.degree. C.
23. A multi-layer decorative laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner
removable from the dry paint layer at room temperature for exposing
an outer surface of the dry paint layer when the pressure-sensitive
adhesive layer adheres the laminate to the substrate surface under
application of pressure and the release liner is peeled away from
the dry paint layer; and a barrier layer formed as a thin, flexible
barrier film disposed between the adhesive layer and the color
layer, the barrier layer film positioned between the adhesive layer
and the color layer and made from a material comprising an acrylic
resinous material and a fine particulate additive comprising a
metal compound, a metal oxide and/or a metal salt dispersed in the
acrylic resinous material in an amount that reduces migration of or
captures migrating discoloration-causing pigments from a painted
surface of the substrate through the adhesive layer to the color
layer, in which the barrier layer material produces a color shift
of less than about 0.30 .DELTA.b* C.I.E. color scale shift units at
60.degree. C.
24. The article according to claim 23 in which the barrier layer is
applied at a dry film thickness in the range of about 0.05 to about
0.20 mil.
25. The article according to claim 23 in which the barrier layer
has a glass transition temperature (Tg) greater than about
160.degree. C.
26. The article according to claim 23 in which the barrier material
has a dry film thickness of not more than about 10% of the total
thickness of the decorative laminate (exclusive of the release
liner).
27. A self-wound multi-layer laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner having
a matte release coat releasably adhered to the lower surface of the
dry paint layer, and an adhesive release coat layer on a side of
the release liner opposite from the dry paint layer, the release
liner and the matte release coat removable from the dry paint layer
at room temperature, the matte release coat transferring a matte
finish to an exposed surface of the dry paint layer when the
pressure-sensitive adhesive layer adheres the laminate to the
substrate surface under application of pressure and the release
liner is peeled away from the dry paint layer, the laminate adapted
for being self-wound into a roll with the pressure-sensitive
adhesive layer in contact with the adhesive release coat layer, the
adhesive release coat layer and the pressure-sensitive adhesive
layer having an unwind release force between them which is lower
that a carrier release force between the matte release coat and the
dry paint layer, such that the adhesive release coat preferentially
releases the liner from contact with the pressure-sensitive
adhesive layer when unwinding the laminate from its roll form,
while the matte release coat maintains contact with the dry paint
layer when the laminate is being unwound from its roll form, and a
barrier layer disposed between the adhesive layer and the color
layer and made from a material that inhibits migration of
discoloration-causing pigments from a painted surface to which the
adhesive side of the laminate is adhered, the barrier material made
of a composition adapted to essentially prevent noticeable color
change caused by the migrating pigments from occurring in the color
layer under room temperature conditions, in which the barrier layer
material is selected from the group consisting of an acrylic
resinous material which has been cross-linked to an amount
sufficient to reduce pigment transmission to the color layer, a
polymeric material containing an adhesion promoter, a high
molecular weight acrylic resinous material having a molecular
weight in excess of 250,000, or a polymeric material containing a
fine particulate dispersed barrier filler material that reduces
pigment transmission to the color layer, the barrier filler
material comprising a metal oxide, a metal compound and/or a metal
salt.
28. The article according to claim 27 in which the barrier layer is
applied at a dry film thickness in the range of about 0.05 to about
0.20 mil.
29. The article according to claim 27 in which the barrier layer
has a glass transition temperature (Tg) greater than about
160.degree. C.
30. The article according to claim 27 in which the barrier material
has a dry film thickness of not more than about 10% of the total
thickness of the decorative laminate (exclusive of the release
liner).
31. The article according to claim 27 in which the laminate further
includes a tie coat for enhancing adhesion between the cross-linked
barrier layer and the pressure-sensitive adhesive layer.
32. The article according to claim 27 in which the barrier layer
material produces a color shift of less than about 0.30 .DELTA.b*
C.I.E. color scale shift units at 60.degree. C.
33. A process for making a multi-layer decorative laminate for
applying a layer of color to a substrate surface, the process
comprising: forming a dry paint layer on a release liner, the dry
paint layer comprising a color layer which includes a binder and a
pigment, the dry paint layer having an upper surface and a lower
surface, applying a pressure-sensitive adhesive layer to the upper
surface of the dry paint layer, the adhesive layer adapted for
adhering the laminate to a substrate surface at room temperature;
the release liner overlying the lower surface of the dry paint
layer, the release liner removable from the dry paint layer at room
temperature for exposing an outer surface of the dry paint layer
when the pressure-sensitive adhesive layer adheres the laminate to
the substrate surface under application of pressure and the release
liner is peeled away from the dry paint layer; and applying a
barrier layer between the adhesive layer and the color layer, the
barrier layer formed as a thin, flexible barrier film positioned
between the adhesive layer and the color layer and made from a
material so as to inhibit migration of discoloration-causing
pigments from a painted surface of the substrate through the
adhesive layer to the color layer sufficiently to essentially
prevent noticeable color change caused by the migrating pigments
from occurring in the color layer under room temperature
conditions, in which the barrier layer material is selected from
the group consisting of an acrylic resinous material which has been
cross-linked to an amount sufficient to reduce pigment transmission
to the color layer, a polymeric material containing an adhesion
promoter, a high molecular weight acrylic resinous material having
a molecular weight in excess of 250,000, or a polymeric material
containing a fine particulate dispersed barrier filler material
that reduces pigment transmission to the color layer, the barrier
filler material comprising a metal oxide, a metal compound and/or a
metal salt.
34. The process according to claim 33 in which the barrier layer is
applied at a dry film thickness in the range of about 0.05 to about
0.20 mil.
35. The process according to claim 33 in which the barrier layer
has a glass transition temperature (Tg) greater than about
160.degree. C.
36. The article according to claim 33 in which the barrier material
is applied at a dry film thickness of not more than about 10% of
the total thickness of the decorative laminate (exclusive of the
release liner).
37. The process according to claim 33 including applying a tie coat
for improving adhesion between the cross-linked barrier layer and
the pressure-sensitive adhesive layer.
38. The process according to claim 33 in which the barrier layer
material produces a color shift of less than about 0.30 .DELTA.b*
C.I.E. color shift units at 60.degree. C.
39. A multi-layer decorative laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner
removable from the dry paint layer at room temperature for exposing
an outer surface of the dry paint layer when the pressure-sensitive
adhesive layer adheres the laminate to the substrate surface under
application of pressure and the release liner is peeled away from
the dry paint layer; and a barrier layer formed as a thin, flexible
barrier film disposed between the adhesive layer and the color
layer, the barrier layer film positioned between the adhesive layer
and the color layer and made from a material so as to inhibit
migration of discoloration-causing pigments from a painted surface
of the substrate through the adhesive layer to the color layer, the
barrier layer comprising one or more of (a)-(c): (a) a material
having a glass transition temperature greater than about 60.degree.
C., (b) a material having a dry film thickness of not more than
about 10% of the total thickness of the decorative laminate, (c) a
material that produces a color shift of less than about 0.30
.DELTA.b* C.I.E. color scale shift units at 60.degree. C.
40. A multi-layer decorative laminate for applying a layer of color
to a substrate surface, the laminate comprising: a dry paint layer
comprising a color layer which includes a binder and a pigment, the
dry paint layer having an upper surface and a lower surface, a
pressure-sensitive adhesive layer overlying the upper surface of
the dry paint layer and adapted for adhering the laminate to a
substrate surface at room temperature; a release liner overlying
the lower surface of the dry paint layer, the release liner
removable from the dry paint layer at room temperature for exposing
an outer surface of the dry paint layer when the pressure-sensitive
adhesive layer adheres the laminate to the substrate surface under
application of pressure and the release liner is peeled away from
the dry paint layer; and a barrier layer formed as a thin, flexible
barrier film disposed between the adhesive layer and the color
layer, the barrier layer film positioned between the adhesive layer
and the color layer and made from a material so as to inhibit
migration of discoloration-causing pigments from a painted surface
of the substrate through the adhesive layer to the color layer, in
which the laminate further includes one or more of (a)-(b): (a) a
tie coat for enhancing adhesion between the barrier layer film and
the pressure-sensitive adhesive layer, (b) an adhesive release coat
layer on a side of the release liner opposite from the dry paint
layer.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part of U.S. application Ser. No.
457,826, filed Jun. 9, 2003, which is a continuation-in-part of
U.S. application Ser. No. 367,611, filed Feb. 14, 2003. These
applications are incorporated herein in their entirety by this
reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to dry paint transfer
laminates, and more particularly, to a multi-layer dry paint
decorative laminate having a barrier layer that inhibits migration
of discoloration-causing pigments into color-producing layers of
the laminate.
BACKGROUND
[0003] Dry paint transfer laminates have been used in the past as
surface coverings that provide an alternative to conventional
painting. Water based paints and oil based paints have well known
shortcomings that can be overcome by the use of decorative dry
paint transfer films as a paint replacement. Environmental problems
such as solvent evaporation from paint systems applied by spray
painting also are avoided by use of decorative dry paint transfer
films.
[0004] Such decorative dry paint transfer films are typically
applied to a substrate surface by an adhesive layer carried by the
film. Use of heat-activated adhesives or water-activated adhesives
can have certain disadvantages that are overcome by use of
pressure-sensitive adhesives, by which the decorative film is
adhered to the substrate surface by application of pressure only,
typically at room temperature. Examples of decorative films having
pressure-sensitive adhesive layers for interior or exterior
applications are disclosed in U.S. Pat. No. 6,096,396 to Patton et
al., U.S. Pat. No. 6,086,995 to Smith, and U.S. Pat. No. 5,229,207
to Paquette et al.
[0005] Decorative films having a pressure-sensitive adhesives are
often adapted to facilitate application to a surface by using
various forms of repositionable adhesives known in the art. The
laminate can be initially applied to a surface, removed
temporarily, and then repositioned, to allow the adhesive to form a
permanent bond. Decorative films having such a repositionable
adhesive layer are described, for example, in the '207 patent to
Paquette et al.
[0006] The present invention comprises a multi-layer laminate
adapted to be placed in contact with a surface which can be a
painted surface. In films overlaying painted surfaces containing
pigmented materials such as dyes or mono azo pigments, the colored
materials may migrate or bleed into the overlaying film. This
causes the finish to discolor. Pigments used in wall paints
containing yellow pigments as a component, or to a lesser extent,
orange or red pigments or dyes, can contain such mono azo
constituents that can migrate from the wall surface through the
overlaid film and into the color layer of the film, causing it to
discolor.
[0007] The present invention provides a multi-layer laminate
adapted for contact with a painted substrate surface containing
organic materials with color constituents that will bleed or
migrate; and the invention addresses a situation, in particular,
where the painted surface containing the migrating organic color
components may not be modified to avoid the color migration
problem. In response to this problem, the invention provides a
laminate containing one or more barrier layers that cooperate to
block or capture the migrating color materials, and in particular,
those containing mono azo pigments. The barrier layer inhibits
discoloration of the colored layer or layers in the laminate caused
by the laminate contacting such a painted surface.
SUMMARY OF THE INVENTION
[0008] Briefly, the invention comprises a multi-layer laminate
adapted to provide a layer of color to a painted surface. The
laminate includes a pressure-sensitive adhesive for overlaying and
contacting the painted surface. The laminate includes one or more
barrier layers that slow or stop the migration of
discoloration-causing pigments from the surface, through the
adhesive layer, to the color layer of the laminate.
[0009] In one embodiment, the barrier will slow or stop the color
change caused by mono azo pigments in interior latex paint. By
applying a barrier layer of specific polymers and/or by addition of
specific additive materials to the barrier layer, the color
migration may be stopped or significantly reduced.
[0010] One embodiment of the invention comprises a decorative dry
paint transfer laminate having a layer of dry paint, a
pressure-sensitive adhesive layer on one side of the dry paint
layer, and a release liner in releasable contact with the dry paint
layer on a side opposite from the pressure-sensitive adhesive. The
dry paint layer comprises a binder and a pigment. A barrier layer
is positioned between the dry paint layer and the
pressure-sensitive adhesive layer. The release liner is removable
from the dry paint layer at room temperature. The
pressure-sensitive adhesive is adapted for adhering the laminate to
a substrate surface at room temperature. The substrate surface can
be a painted wall surface containing organic materials with color
that can bleed or migrate. The pressure-sensitive adhesive layer
adheres the laminate to the substrate surface under application of
pressure. The release liner is then peeled away from the dry paint
layer. The barrier layer comprises a thin, flexible film made from
a material that stops or appreciably reduces migration of
discoloration-causing constituents migrating from the painted
surface through the adhesive layer to the color layer. In one
embodiment, the barrier layer can comprise a polymeric material
having a cross-linking density sufficient to inhibit transmission
of discoloration-causing pigments and/or a dispersed additive that
may capture or retard the migration of discoloration-causing
pigments. The barrier layer is particularly useful in retarding or
inhibiting the transmission of azo-type pigments and is present at
a low coat weight or thickness which does not significantly
increase the overall thickness of a decorative film. In one
embodiment, the barrier thickness is no more than about 10% of the
total thickness of the decorative film (excluding the outer
releasable carrier film).
[0011] These and other aspects of the invention will be more fully
understood by referring to the following detailed description and
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic cross-sectional view illustrating one
embodiment of a multi-layer dry paint transfer laminate according
to principles of this invention.
[0013] FIG. 2 is a schematic illustration of the dry paint transfer
laminate self-wound into a roll form.
[0014] FIG. 3 is a schematic cross-sectional view showing an
alternative embodiment of a dry paint layer contained in the
laminate.
[0015] FIG. 4 is a schematic cross-sectional view showing another
alternative embodiment of the dry paint layer.
[0016] FIG. 5 is a schematic cross-sectional view illustrating an
alternative embodiment of the dry paint layer of FIG. 4.
[0017] FIG. 6 is a schematic cross-sectional view illustrating an
embodiment containing a support layer.
[0018] FIG. 7 is a schematic cross-sectional view illustrating an
embodiment containing a barrier layer.
[0019] FIG. 8 is a schematic illustration of a process for
co-extruding a support layer and an adhesive layer used in one
embodiment of the invention.
[0020] FIG. 9 is a schematic illustration of a process for
co-extruding a support layer and an adhesive layer used in another
embodiment of the invention.
[0021] FIG. 10 is a schematic view illustrating one embodiment of
the invention which includes a dry paint layer, a barrier layer and
a tie coat for the adhesive layer.
DETAILED DESCRIPTION
[0022] Referring to FIG. 1, a multilayer dry paint transfer
laminate 20 is adapted for use as a surfacing film. The multilayer
laminate includes a pigmented dry paint layer 22 comprising a
synthetic resinous binder containing a dispersed pigment. The dry
pigmented paint layer 22, also referred to herein as a color layer,
generally can be a monocoat pigmented layer as illustrated in FIG.
1, or it can be combined with additional pigmented paint layers,
coatings or print coats described below. In each instance, these
decorative elements of the multilayer dry paint transfer film will
be referred to generally as a decorative dry paint layer. In the
illustrated FIG. 1 embodiment, the dry paint layer 22 has an upper
surface 24 and a lower surface 26. The multilayer laminate further
includes a dry adhesive layer 28 overlying and adhered to the upper
surface 24 of the dry paint layer, and a flexible and foldable
release liner 30 overlying and releasably adhered to the lower
surface of the dry paint layer. The release liner has a matte
release coat 32 on its inner surface for releasably adhering the
release liner 30 to the lower surface 26 of the dry paint layer 22.
The release liner 30 is adapted to be peeled away from the dry
paint layer under an applied release force, also referred to herein
as a carrier release function. The matte release coat 32 separates
from the dry paint layer 22 but remains adhered to the release
liner 30 when the release liner is peeled away from the dry paint
layer. The release liner 30 also has an adhesive release coat layer
34 on a surface opposite from the dry paint layer. An exposed outer
surface 38 of the adhesive release coat layer 34 is adapted for
releasably contacting an exposed outer surface 40 of the adhesive
layer 28 when the laminate is wound in a roll form illustrated in
FIG. 2.
[0023] Referring to FIG. 2, the dry paint transfer laminate 20 is
self-wound into a roll form with the outer exposed surface 38 of
the adhesive release coat layer 34 in releasable contact with the
exposed outer surface 40 of the adhesive layer 28. Thus, when the
dry paint transfer laminate 20 illustrated in FIG. 2 is unwound,
the adhesive release coat layer 34 on the release liner separates
from the outer surface 40 of the adhesive layer 28 and remains
adhered to the release liner 30. The matte release coat 32 remains
adhered to the dry paint layer.
[0024] FIG. 3 illustrates a dry paint transfer laminate 42 which is
identical to the dry paint transfer laminate 20 illustrated in FIG.
1, except that the decorative dry paint layer includes an optically
transparent synthetic resinous clear coat layer 44 adhered to the
lower surface 26 of the pigmented dry paint layer 22. In this
embodiment, the outer clear coat layer 44 is in releasable contact
with the matte release coat 32 of the release liner 30. When the
release liner 30 is peeled away from the clear coat layer 44, the
matte release coat 32 separates from the clear coat layer 44 and
remains adhered to the release liner 30.
[0025] FIG. 4 illustrates a multilayer dry paint transfer laminate
46 which is identical to the dry paint transfer laminate 42
illustrated at FIG. 3, except that the decorative dry paint layer
further includes a decorative print coat layer 48 between the
pigmented dry paint layer 22 and the clear coat layer 44. The
decorative print coat layer provides a decorative print pattern,
and the pigmented dry paint layer 22 provides a background color
and opacity for the decorative dry paint layer. The print pattern
and background color are visible through the outer clear coat layer
44.
[0026] FIG. 5 illustrates a multilayer dry paint transfer laminate
50 which is identical to the dry paint transfer laminate 46
illustrated in FIG. 4, except that a second decorative print coat
layer 52 can be printed or coated between the print coat layer 48
and the outer clear coat layer 44.
[0027] Additional print coat layers may be used. For instance, the
multilayer laminate may contain up to about five or more print
coats, and in one embodiment, preferably three or four print coat
layers are used. The layers may have a print or design pattern
using conventional printing methods, such as gravure, flexography,
silk screen, or ink jet printing.
[0028] FIG. 6 illustrates an embodiment of a multilayer dry paint
transfer laminate 54 which is identical to the multilayer laminate
20 illustrated in FIG. 1, except that the laminate 54 includes a
flexible reinforcing layer 56 (also referred to herein as a support
layer) between the dry paint layer 22 and the adhesive layer 28.
The reinforcing layer 56 provides a means of structural support for
the decorative dry paint layer and can provide additional opacity
for the decorative dry paint layer. The reinforcing layer has a
tensile strength which exceeds that of the dry paint layer or
layers.
[0029] FIG. 7 illustrates another embodiment of the dry paint
transfer laminate 58 which is identical to the laminate 20
illustrated in FIG. 1, except that the laminate 58 includes a
flexible barrier layer 60 between the pigmented dry paint layer 22
and the adhesive layer 28. The intervening barrier layer can be
used to inhibit or prevent undesired migration of constituents
between the adhesive layer and the paint coat layer. Such barrier
properties can include reducing or avoiding undesired discoloration
by inhibiting or preventing migration of pigments from an
underlying substrate surface through the adhesive layer to the dry
paint layer.
[0030] The embodiment of FIGS. 6 and 7 show separate support
(reinforcing) and barrier layers. In addition, the barrier layer 60
may be included as a layer in the FIG. 6 embodiment. In this
instance, the barrier layer may be applied between the dry paint
layer and the support (reinforcing) layer, or the barrier layer may
be applied between the adhesive layer and the support layer.
[0031] The dry paint layer 22 may have a thickness generally of
about 0.5 to about 1.5 mils, in one embodiment about 0.5 to about
1.2 mils, and in another embodiment from about 0.5 to about 0.9
mil. The thickness of the adhesive layer may range generally from
about 0.4 to about one mil, in one embodiment from about 0.4 to
about 0.8 mil, and in another embodiment from about 0.4 to about
0.6 mil. The thickness of the release liner may range generally
from about 0.5 to about 2 mils, in one embodiment from about 0.5 to
about 1.5 mils, and in another embodiment from about 0.85 to about
1.05 mils. The thickness of the matte release coat layer may range
generally from about 0.05 to about 0.3 mil, and in one embodiment
from about 0.1 to about 0.2 mil. The thickness of the adhesive
release coat layer may range from about 0.04 to about 0.2 mil, in
one embodiment from about 0.04 to about 0.15 mil, and in another
embodiment from about 0.04 to about 0.08 mil. The thickness of the
outer clear coat layer may range generally from about 0.05 to from
about 0.4 mil, and in one embodiment from about 0.05 to about 0.3
mil.
[0032] The thickness of the decorative print coat layers may range
from about 0.02 to about 0.15 mil, and in one embodiment from about
0.02 to about 0.08 mils.
[0033] The reinforcing layer may have a thickness generally of
about 0.3 to about 1.4 mils. In one embodiment the thickness can be
about 0.3 to about 1.1 mils, in another embodiment about 0.3 to
about 0.8 mil, and in a further embodiment about 0.3 to about 0.5
mil. When the reinforcing layer is used, the overall thickness of
the combination of the dry paint layer and the support layer may be
in the range of about 0.5 to about 1.5 mils, in another embodiment
about 0.5 to about 1.2 mils, and in a further embodiment from about
0.5 to about 0.9 mil.
[0034] The barrier layer may have a thickness in the range of about
0.01 to about 0.1 mil, and in one embodiment about 0.05 to about
0.1 mil, and in another embodiment from about 0.01 to about 0.02
mil.
[0035] Each of the foregoing thicknesses are dry film thicknesses.
The laminates may have any width or length that is suitable for its
end use. For example, the width may range from about one to about
200 cm, and in one embodiment from 10 to 100 cm, and in another
embodiment from about 30 to about 40 cm. The length may range from
about 10 to about 6500 meters, and in one embodiment from about 15
to about 1000 meters. The laminates may take the form of flat
sheets or as a self-wound roll form as illustrated in FIG. 2.
Dry Paint Layer
[0036] The dry paint layers may comprise independently one or more
polymeric binders or resins, and one or more pigments. The
reinforcing layer and barrier layer may comprise one or more
polymeric binders or resins, and optionally one or more pigments.
The transparent outer clear coat layer may comprise one or more
polymeric binders or resins. These layers may be made from solvent
cast liquid coating or paint compositions comprising the one or
more binders or resins and one or more pigments (if used). These
compositions may be dispersed in water or one or more organic
solvents, and optionally may contain one or more additional
additives for controlling properties such as rheological properties
or barrier properties. The dry paint layers, or the transparent
outer clear coat layer, or the reinforcing layer or barrier layer
may each comprise independently one or more extruded layers.
[0037] The binder or resin may comprise any binder or resin
conventionally used in coating or paint formulations. The binder
may comprise a thermoplastic or thermosetting resin. The binder or
resin may be a synthetic resin or a natural resin. The binder or
resin may comprise a film forming material which may be cast as a
solvent-based coating or in one embodiment may be an extrudable
film forming material. Examples of useful binders or resins
generally include acrylic, vinyl, polyester, alkyd, butadiene,
styrene, urethane and epoxy resins and phthalic acid or anhydride
resins, and mixtures thereof. More specifically, the binder or
resin may include one or more polystyrenes, polyolefins,
polyamides, polyesters, polycarbonates, polyvinyl chloride,
polyvinyl alcohol, polyethylene vinyl alcohol, polyurethanes,
polyacrylates, polyvinyl acetates, ionomer resins, and mixtures
thereof.
[0038] The binder or resin may comprise vinyl and vinylidene
polymers or copolymers containing units such as vinyl acetate,
vinyl chloride, and vinylidene chloride; hydrocarbon polymers and
copolymers containing ethylene or propylene units and oxygenated or
halogenated derivatives of ether, butadiene, oxygenated butadiene,
isoprene, oxygenated isoprene, butadiene-styrene, butadiene vinyl
toluene, and isoprene-styrene; polymers or copolymers containing
units of acrylic acid, methacrylic acid, their esters, or
acrylonitrile; vinylic hydrocarbon monomers reacted with
unsaturated materials such as the reaction product of maleic acid
or anhydride with styrene; and, broadly, various other resinous
rubber-like elastomeric latex polymers and copolymers of
ethylenically unsaturated monomers and polymers obtainable in
stable aqueous latex form. The binder or resin may comprise a
copolymer of vinyl chloride and vinyl acetate.
[0039] The polyolefins may be characterized as having a melt index
or melt flow rate of less than about 30, and in one embodiment less
than about 20, and in one embodiment less than about 10 as
determined by ASTM Test Method 1238. The polyolefins include
polymers and copolymers of ethylene, propylene, 1-butene, etc., or
blends of mixtures of such polymers and copolymers.
[0040] Various polyethylenes may be used including low, medium, and
high density polyethylenes. The low density range for the
polyethylenes may be from about 0.910 to about 0.925 g/cm.sup.3,
the medium density range may be from about 0.925 to about 0.940
g/cm.sup.3, and the high density range may be from about 0.940 to
about 0.965 g/cm.sup.3. An example of a useful low density
polyethylene is Rexene 1017 available from Huntsman.
[0041] The propylene homopolymers which may be used either alone or
in combination with a propylene copolymer include a variety of
propylene homopolymers such as those having melt flow rates from
about 0.5 to about 20 as determined by ASTM Test D 1238, condition
L.
[0042] The polyamide resins include resins available from EMS
American Grilon Inc., Sumter, S.C. under the general tradename
Grivory such as CF-65, CR-9, XE-3303 and G-21. The polyamide resins
also include those available from, for example, Union Camp of
Wayne, N.J. under the Uni-Rez product line, and dimer-based
polyamide resins available from Bostik, Emery, Fuller, and Henkel
(under the Versamid product line).
[0043] The polystyrenes include homopolymers as well as copolymers
of styrene and substituted styrene such as alpha-methyl styrene.
Examples of styrene copolymers and terpolymers include:
acrylonitrile-butene-styrene (ABS); styrene-acrylonitrile
copolymers (SAN); styrene butadiene (SB); styrene-maleic anhydride
(SMA); and styrene-methyl methacrylate (SMMA); etc.
[0044] The polyurethanes include aliphatic as well as aromatic
polyurethanes.
[0045] The polyesters may be prepared from various glycols or
polyols and one or more aliphatic or aromatic carboxylic acids.
Polyethylene terephthalate (PET) and PETG (PET modified with
cyclohexanedimethanol) are useful film forming materials which are
available from a variety of commercial sources including Eastman.
For example, Kodar 6763 is a PETG available from Eastman Chemical;
Another useful polyester from DuPont is Selar PT-8307 which is
polyethylene terephthalate.
[0046] Acrylate polymers and copolymers and alkylene vinyl acetate
resins (e.g., EVA polymers) may be used. Examples include Escorene
UL-7520 (Exxon), a copolymer of ethylene with 19.3% vinyl acetate;
Nucrell 699 (DuPont), an ethylene copolymer containing 11% of
methacrylic acid, etc.
[0047] Ionomer resins (polyolefins containing ionic bonding of
molecular chains) may be used. Examples of ionomers include
ionomeric ethylene copolymers such as Surlyn 1706 (DuPont) and
Surlyn 1702 from DuPont.
[0048] Polycarbonates also are useful, and these are available from
the Dow Chemical Co. (Calibre) G.E. Plastics (Lexan) and Bayer
(Makrolon).
[0049] The pigment may be any pigment used in making decorative
coatings. These include opacifying pigments, such as titanium
dioxide and zinc oxide, as well as tinting pigments such as carbon
black, yellow oxides, brown oxides, tan oxides, raw and burnt
sienna or umber, chromium oxide green, phthalocyanine green,
phthalocyanine blue, ultramarine blue, cadmium pigments, and
chromium pigments. The pigments include organic reds such as azo
reds, quinacridone red and perylene red as well as organic yellows
such as diarylide yellow. Mixed metal oxide pigments may be used.
Filler pigments such as clay, silica, talc, mica, woloastonite wood
flour, barium sulfate, calcium carbonate, aluminum silicate, and
the like can be added as well in conventional amounts traditionally
used in coating and paint formulations.
[0050] The solvent may be an organic-based solvent, such as a
ketone, ester, aliphatic compound, aromatic compound, alcohol,
glycol, glycol ether, etc. These include methylethyl ketone,
methylisobutyl ketone, ethyl acetate, white spirits, alkanes,
cycloalkanes, benzene, hydrocarbon substituted aromatic compounds
(e.g., toluene, the xylenes, etc.), isoparaffinic solvents, and
combinations of two or more thereof. Alternatively, water or a
water-based solution may be used to form an aqueous emulsion with
the binder or resin. Water-based solutions include water-alcohol
mixtures. The solvent or water is sufficiently volatile so that
when applied to a substrate, the solvent evaporates leaving behind
the binder or resin, pigment (if used), and any other additional
non-volatile components.
[0051] Additional ingredients that may be used include wetting
agents; plasticizers; suspension aids; thixotropic agents such as
silica; water repellant additives such as polysiloxane compounds;
fire retardant additives; biocides; defoamers; and flow agents.
[0052] The pigment concentration for the liquid paint or coating
composition used to form the dry paint layers may range from about
10 to about 30% by weight, and in one embodiment about 13 to about
27% by weight. The binder or resin concentration may range from
about 20 to about 40% by weight, and in one embodiment about 22 to
about 37% by weight. The water or organic solvent concentration may
range from about 30 to about 70% by weight, and in one embodiment
about 40 to about 60% by weight. The additional ingredients such as
wetting agents, suspension agents, etc., may have concentrations up
to about 5% by weight. The coating or paint compositions used in
making the dry paint layers may have a pigment to binder volume
concentration in the range of about 5 to about 35%, and in one
embodiment 10 to about 30%.
[0053] The liquid paint or coating compositions used for making the
dry paint layers may be blended using known techniques. The dry
paint layer may comprise a single coat or multiple coats of paint
and is in the form of a continuous layer, while the printed
decorative layers may independently be in the form of continuous or
discontinuous layers. When multiple coats for the dry paint layer
are used, each coat may have the same or a different formulation.
The print coats may have the same color or a different color than
the dry paint layer, or the print coats may have the same color, or
they may have colors that are different from each other. The dry
paint layer may be used to provide background color while the print
layers may be used to provide a desired pattern or design.
[0054] (a) Transparent Top Coat Layer
[0055] The transparent outer clear coat layer may comprise a single
coating layer or multiple coats, and may comprise any of the
resinous materials described above. When multiple coats are used,
each coat may have the same or a different formulation. As
mentioned previously, the outer clear coat layer may be solvent
cast (aqueous or organic solvent based) or the outer clear coat
layer may be extruded. The outer clear coat layer, in one
embodiment, provides enhanced scuff resistance, stain resistance
and/or recoatability to the dry paint film layer or layers
underlying it. Enhanced recoatability facilitates the subsequent
application of another dry paint film layer or printed decorative
layer over it, or the application of conventional paint or
decorative dry paint films.
[0056] (b) Reinforcing or Support Layer
[0057] The reinforcing or support layer may be formed from any of
the binder or resin materials described above. This layer may be
formed from a solution or an emulsion and applied using any of the
coating techniques described below. This layer also may be
extruded. The reinforcing layer may contain one or more of the
above-described pigments to enhance opacity of the finished
laminate. The concentration of pigment in the reinforcing layer,
when used, may range up to about 10% by weight, and in one
embodiment about 6 to about 10% by weight.
[0058] The dry paint layers, outer clear coat layer or reinforcing
layer independently may contain inorganic fillers or other organic
or inorganic additives to provide desired properties such as
appearance properties (clear, opaque or colored films), durability
and processing characteristics. Examples of useful materials
include calcium carbonate, titanium dioxide, metal particles,
fibers, flame retardants, antioxidant compounds, heat stabilizers,
light stabilizers, ultraviolet light stabilizers, antiblocking
agents, processing aids, and acid acceptors.
[0059] One or more of the dry paint layers, outer clear coat layer
or reinforcing layer may contain a minor amount of an adhesive
resin to enhance the adhesion of the dry paint layer to the outer
clear coat layer and/or the support layer. Also, or alternatively,
tie coat layers of an adhesive resin can be used between the dry
paint layers and either the outer clear coat layer or the
reinforcing layer. The adhesive resin for the tie coat can be an
acrylic resin adhesive, or it can be an ethylene/vinyl acetate
copolymer adhesive such as those available from DuPont under the
tradename Elvax. The adhesive resins available from DuPont under
the tradename Bynel also may be used.
[0060] In one embodiment, the dry paint layers, the outer clear
coat layer and/or the reinforcing layer are flexible, but
non-stretchable and non-elastic at room temperature.
Adhesive Layer
[0061] The dry adhesive layer may comprise a pressure-sensitive
adhesive (PSA) which bonds the decorative laminate to a substrate
surface, under applied pressure, at room temperature. The adhesive
layer may be a continuous or discontinuous layer, and it may
comprise one or a mixture of two or more adhesives. The adhesive
layer may be a patterned adhesive layer with relatively strong
adhesive tack level in some areas and a relatively weak adhesive in
other areas.
[0062] In one embodiment, the adhesive layer is a repositionable
adhesive, having a low initial tack that allows slight movement of
the laminate to allow positioning adjustments prior to forming a
permanent bond. In one embodiment, the adhesive has a suppressed
initial level of tack at room temperature that allows the laminate
to adhere to a substrate surface and be repositioned thereon
followed by removal of the matte release liner from the decorative
dry paint layer. The adhesive layer undergoes a subsequent buildup
of adhesion due to the passage of time sufficient to permanently
bond the dry paint layer to the substrate. In one embodiment, the
adhesive layer is characterized by producing only a limited amount
of ooze beyond the borders of the laminate when the laminate is
applied to a substrate. In one embodiment, no ooze is produced.
[0063] In one embodiment of the invention described below, the
pressure-sensitive adhesive comprises a cross-linked acrylic
resinous material, and more particularly, a cross-linked acrylic
emulsion. A particularly useful adhesive material comprises an
internally cross-linked acrylic emulsion. These pressure-sensitive
adhesive materials provide a useful combination of low tack, peel
and flow properties with a sufficient level of cohesive strength at
a useful (thin) coat weight for providing the differential release
properties described below. High molecular weight acrylic adhesives
and externally cross-linked acrylic adhesives also may be used to
produce the desired combination of functional properties.
[0064] The adhesive may comprise a rubber based adhesive, acrylic
adhesive, vinyl ether adhesive, silicone adhesive, or mixture of
two or more thereof. The adhesive may be applied to the laminate as
a hot melt, solvent-based or water based adhesive. The adhesive
materials that are useful may contain as a major constituent an
adhesive polymer such as an acrylic-type polymer; block copolymer;
natural, reclaimed, or styrene-butadiene rubber; tackified natural
or synthetic rubber; a copolymer of ethylene and vinyl acetate; an
ethylene-vinyl-acrylic terpolymer; polyisobutylene; or poly(vinyl
ether). Other materials may be included in the adhesive such as
tackifying resins, plasticizers, antioxidants, fillers, and
waxes.
[0065] A description of useful pressure-sensitive adhesives may be
found in Encyclopedia of Polymer Science and Engineering, Vol. 13.
Wiley-Interscience Publishers (New York, 1988). Additional
description of useful pressure-sensitive adhesives may be found in
Encyclopedia of Polymer Science and Technology, Vol. 1,
Interscience Publishers (New York, 1964).
[0066] Pressure-sensitive adhesives that may be used include the
hot melt pressure-sensitive adhesives available from H.B. Fuller
Company, St. Paul, Minn. as HM-1597, HL-2207-X, HL-2115-X,
HL-2193-X. Other useful pressure-sensitive adhesives include those
available from Century Adhesives Corporation, Columbus, Ohio.
[0067] Conventional PSAs, including silicone-based PSAs,
rubber-based PSAs, and acrylic-based PSAs are useful. Another
commercial example of a hot melt adhesive is H2187-01, sold by Ato
Findley, Inc., of Wauwatusa, Wis. In addition, rubber based block
copolymer PSAs described in U.S. Pat. No. 3,239,478 to Harlan also
can be used. This patent is incorporated by reference for its
disclosure of such hot melt adhesives.
[0068] The adhesive compositions may contain at least one solid
tackifier resin component. A solid tackifier is defined herein as
one having a softening point above 80.degree. C. When the solid
tackifier resin component is present, the adhesive compositions may
comprise from about 40% to about 80% by weight of a thermoplastic
elastomer component, in one embodiment from about 20% to about 60%
by weight, and in another embodiment from about 55% to about 65% by
weight of a solid tackifier resin component. The solid tackifier
reduces the modulus of the mixture sufficiently to build tack or
adhesion. Also, solid tackifiers (particularly the higher molecular
weight solid tackifiers (e.g., Mw greater than about 2000) and
those having a lower dispersity (Mw/Mn=less than about 3) may be
less sensitive to migration into the polymer film layer. This is
desirable since migration of tackifier into the film layer may
cause dimensional instability.
[0069] The solid tackifier resins include hydrocarbon resins,
rosin, hydrogenated rosin, rosin esters, polyterpene resins, and
other resins which exhibit the proper balance of properties. A
variety of useful solid tackifier resins are available commercially
such as terpene resins which are sold under the trademark Zonatac
by Arizona Chemical Company, petroleum hydrocarbons resins such as
the resins sold under the trademark Escorez by Exxon Chemical
Company, or Wingtack 95, a synthetic tackifier resin available from
Goodyear, Akron, Ohio.
[0070] The modulus of adhesive mixtures to be coextruded also may
be lowered by the incorporation of liquid rubbers, i.e., liquid at
room temperature. The liquid rubbers generally will have an Mw of
at least 5,000 and more often at least 20,000. Incorporation of
liquid rubbers in amounts of less than 10%, and even less than 5%
by weight based on the overall weight of the adhesive formulation
results in adhesives which are coextrudable with the polymeric film
materials. The incorporation of a liquid rubber may produce an
adhesive having increased tack and adhesion. Liquid block
copolymers such as liquid styrene-isoprene block copolymers may be
used. Other liquid rubbers which may be incorporated into the
adhesive mixture include liquid styrene-butadiene rubbers, liquid
butadiene rubbers, ethylene-propylene rubbers, etc.
[0071] The adhesive layer also may contain one or more pigments to
enhance the opacity of the paint film layers overlying it and
permit use of thinner paint film layers to achieve desired levels
of opacity. Any of the pigments identified above may be used.
Examples include titanium dioxide and carbon black. The pigment
volume concentration may range up to about 10%, in one embodiment
from about 5% to about 10%, and in another embodiment from about 2%
to about 8%.
[0072] The adhesive compositions also may include other materials
such as antioxidants, heat and light stabilizers, ultraviolet light
absorbers, fillers, colorants, antiblocking agents, reinforcing
agents, and processing aids.
[0073] The adhesive compositions may contain inorganic fillers and
other organic and inorganic additives to provide desired
properties. Examples of useful fillers include calcium carbonate,
titanium dioxide, metal particles, and fibers.
Barrier Layer
[0074] The barrier layer may comprise any of the acrylate polymers
or copolymers described above, polyvinyl alcohol, copolymers
derived from ethylene and vinyl acetate, and copolymers derived
from ethylene, vinyl acetate and polyvinyl alcohol. The barrier
layer may comprise a polymer blend derived from polyvinyl alcohol,
urethane, Cymel 385 (a product of Cytec identified as a melamine
formaldehyde resin) and a polyaziridine (e.g., NeoCryl CX100 which
is identified as trimethol-tris N (methyl aziridinyl) proprionate
and is available from Avecia Resins), the weight ration of
polyvinyl alcohol to urethane in one embodiment being about 20:80.
The following examples illustrate specific coating compositions
which may be used in forming the barrier layer: TABLE-US-00001
Percent by Weight Barrier Layer No. 1 Elvacite 2042 (product of
Ineos 20 identified as an ethyl methacrylate copolymer) Tolune 48
Methyl ethyl ketone 32 Barrier Layer No. 2 Adcoat 61WG178 (product
of Rohm and Haas 55.55 identified as a solution of acrylic polymer)
Syloid 234 (product of Grace Davidson 0.10 identified as synthetic
amorphous silica) N-propanol 44.35 Barrier Layer No. 3 Adcoat 74.07
N-propanol 25.83 Syloid 234 0.10 Barrier Layer No. 4 Adcoat 61WG178
55.55 N-propanol 44.35 Syloid 234 0.10 Desmodur CB 75N (product of
Bayer 0.44 identified as an oligomeric toluene diisocyanate)
Barrier Layer No. 5 Adcoat 61WG178 74.07 N-propanol 25.83 Syloid
234 0.10 Desmodur CB 75N 0.44 Barrier Layer No. 6 Adcoat 61WG178
58.0 R-900 TiO.sub.2 (product of DuPont identified 15.00 as rutile
titanium dioxide) N-propanol 24.0 Isobutanol 3.00 Barrier Layer No.
7 Adcoat 61WG178 58.00 R-900 TiO.sub.2 15.00 N-propanol 24.00
Isobutanol 3.00 Desmodur CB 75N 0.88 Barrier Layer No. 8 Air Vol
523 (product of Air Products 5.0 identified as polyvinyl alcohol)
Water 47.5 Isopropanol 47.5
[0075] As mentioned previously, the substrate surface contacted by
the decorative laminate can comprise a painted surface having
pigment materials containing color constituents which can migrate
into the decorative film and through the adhesive layer to the
color layer, causing discoloration. The barrier layer stops or
retards the transmission of undesired discoloration-causing
pigments sufficient to maintain discoloration or color shift of the
color layer to within a level which is essentially unnoticeable for
a useful life of the decorative film. Normal use conditions under
which the decorative film is applied and normally in use are
defined as temperatures from about 4.degree. C. (40.degree. F.) to
about 35.degree. C. (90.degree. F.), and more particularly, from
about 15.degree. C. (60.degree. F.) to about 27.degree. C.
(80.degree. F.). To approximate the amount of color shift that may
occur during an estimated useful life of the film under normal use
conditions, film samples are tested by accelerated aging techniques
and measured for color shift under those conditions. (Higher
temperatures accelerate migration of discoloration color
constituents.) In one embodiment, color shift is measured by
comparing the color of an interior latex test sample with an
interior latex color standard and then subjecting the test sample
to a 60.degree. C. (140.degree. F.) environment for approximately
400 hours (16 days). The test sample is then measured for color
shift and compared with the standard to determine the amount of
color shift. According to one test, color shift is measured under
ASTM 805 test procedures, and the unit of measure is C.I.E. color
units on the .DELTA.b* (yellow/blue) scale, although other color
shift measurements can be used to determine whether color shift is
within a specified range. These color shift measuring techniques
are useful in evaluating whether a color shift is acceptably low by
measuring the color shift in a blue painted sample caused by
migration of yellow color constituents from mono azo pigments or
dyes. In one embodiment, the color shift is considered sufficiently
low to be within an acceptable range if testing at 60.degree. C.
for 400 hours produces a color shift equal to or less than about
0.30 C.I.E. .DELTA.b* color units.
[0076] The barrier layer comprises a thin, flexible polymeric film
which, in one embodiment, can be cross-linked to enhance barrier
properties. One embodiment of the barrier layer comprises a
non-pigmented acrylic resinous material which is cross-linked at a
cross-linking density sufficient to retard transmission of mono azo
pigments to within the acceptable level. One embodiment of this
barrier layer comprises a relatively low molecular weight acrylic
polymer which is cross-linked with a melamine resin. A low
molecular weight acrylic resin suitable for the barrier layer has a
molecular weight below about 100,000. One such cross-linked acrylic
barrier layer (identified in more detail in Example 9) is the
acrylic polymer (Adcoat 61WG178 from Rohm and Haas) which has a
molecular weight of about 50,000. The cross-linking increases the
molecular weight and raises the softening point of the barrier coat
and creates a network at the molecular level that retards
transmission of the azo color constituents through the barrier
layer.
[0077] The use of a cross-linked polymeric material as a barrier
coat can be useful in producing the desired retardation, but in
some instances, the cross-linking of the resinous material can
reduce adhesion to the PSA layer. In some instances, it is
desirable to include a tie coat between the base coat and the PSA
layer. One tie coat layer which has been shown to improve adhesion
comprises a thin coating of a material similar to the pigmented
base coat layer used in the decorative film. One example of such a
tie coat is the plasticized vinyl tie coat shown in Example 9.
[0078] The PSA layer can be applied to the barrier coat by direct
coating or casting of the PSA onto the previously formed barrier
coat. Alternatively, the PSA can be separately cast on a temporary
carrier and then transfer-laminated from the carrier to the barrier
coat. Experimental tests have shown that adhesion between the
barrier coating and the adhesive and the resistance to migration of
color constituents is better when the adhesive is coated directly
onto the barrier coating as opposed to transfer-lamination of the
cast adhesive.
[0079] In another embodiment, the barrier layer can be made from a
thermoplastic (non-cross linked or lightly cross linked) polymeric
material. One such material is the low molecular weight acrylic
material (61WG178) described above. To increase the material's
resistance to migration of color constituents, a fine particulate
filler material or additive can be dispersed in the barrier
material. The filler or additive can have scavenging properties, or
properties similar to a laking agent to which migrating pigments
can attach, or the filler material can physically retard
transmission rate to a sufficiently low level. Materials that have
been found to reduce, capture, or stop migration of mono azo
pigments include fumed aluminum oxide, metal phosphate compounds
and/or titanium dioxide, although other metal salts, or oxides, or
metal compounds also can be used to produce similar results. One
metal compound useful in the barrier coat comprises an aluminum
zirconium phosphosilicate available as Xtain A from Halox. Tests
have shown good color shift results for low molecular weight
thermoplastic acrylic resinous barrier materials containing these
types of filler or additive materials. These materials also reduce
color shift in a cross-linked acrylic resinous barrier coat
layer.
[0080] In one embodiment of the invention, in which the barrier
coat comprises a thermoplastic resinous material containing a
dispersed filler for retarding color transmission, adhesion to the
PSA layer can be enhanced by addition of a dispersed adhesion agent
to the barrier coat. The low molecular weight thermoplastic acrylic
barrier coat can have adhesion properties enhanced by addition of
polyvinyl pyrrolidone homopolymer (PVP). This barrier coat produces
good adhesion to PSA layers which are either direct-coated or
transfer-laminated to the barrier coat. The PVP is compatible with
the acrylic base polymer material and the solvents used in the
system and also increases adhesion to the PSA layer. One source of
the PVP is International Specialty Products (ISP) identified as PVP
K80.
[0081] Another embodiment of the barrier layer comprises a
thermoplastic polymeric material having a sufficiently high
molecular weight to retard color transmission to within desirable
limits. A suitable high molecular weight barrier material has a
molecular weight in excess of 250,000. One barrier material
comprises a high molecular weight acrylic resinous material such as
a polymethyl methacrylate (PMMA) having a molecular weight of about
350,000. This barrier material can produce the acceptable color
shift results without addition of adhesion promoters or additives
and also can be used without an additional tie coat layer to
promote adhesion to the PSA.
[0082] The barrier layer of this invention is applied at a
sufficiently low coat weight to produce a dry film thickness within
a range of about 0.05 to about 0.20 mil. The barrier coat is
sufficiently thin so as to not add significant thickness to the
decorative portion (excluding the release liner) of the multi-layer
laminate. In one embodiment, film thickness of the barrier layer is
not more than about ten percent (10%) of the total thickness of the
decorative portion of the film.
[0083] The barrier layer also is resistant to softening at elevated
temperatures, and in one embodiment, the barrier layer has a glass
transition temperature (T.sub.g) greater than about 60.degree.
C.
[0084] The addition of the barrier layer and the adjoining tie coat
layer (if used) does not impact the differential release properties
of the decorative film. Adhesion of the barrier layer to the PSA
layer is sufficient to not appreciably reduce the peel force
characteristics of the laminate in its self-wound form as described
herein.
Matte Release Liner
[0085] The release liner may independently comprise paper, polymer
film, or a combination thereof. The release liner, in one
embodiment, is thermally stable, non-elastomeric and
non-stretchable at room temperature.
[0086] Although paper of any weight may be used as a release liner,
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 preferred. The
term "ream" as used herein equals 3000 square feet.
[0087] Alternatively, the release liner may independently comprise
a polymeric film, and examples of polymeric films include
polyolefin, polyester, and combinations thereof. The release liner
preferably may be formed from a flexible, foldable, heat-resistant,
substantially inelastic, self-supporting temporary carrier film or
casting sheet as is known in the art of dry paint transfer films.
The release liner is preferably an oriented polyester film such as
polyethylene terephthalate (PET) available as Mylar, a trademark of
DuPont, or Hoechst Celanese Hostaphan 2000 polyester film, for
example.
[0088] The release liner provides structural integrity to the
laminate until the liner is removed upon application of the
laminate to a substrate surface.
[0089] The matte release coat layer may comprise any of the above
identified binders or resins which provide a level of tack or
adherence between the release coat layer and the decorative dry
paint layer, which may comprise either the color coat layer, the
outer clear coat layer, or the decorative print layer. The tack
level of the matte release coat layer is sufficient to prevent
separation of the release coat layer from the adhered dry paint
layer during the process of forming the dry paint transfer laminate
and during normal handling of the laminate, including forming it in
its self-wound orientation, unwinding it, and applying it to the
substrate surface. The matte release coat also continues to have
sufficient release properties to facilitate separation between the
release coat layer and the adhered dry paint layer after having
applied the laminate to the substrate.
[0090] The matte release coat formulation comprises a coating which
can be applied to the release liner by conventional casting
techniques such as gravine printing. The preferred coating
composition is a thermosetting resinous material which, when
exposed to heat for drying it, also cross links and permanently
bonds as a surface film adhered to the release liner. The solids
contained in the matte release coat preferably include, as a
principal component, one or more crosslinking agents to provide
good adhesion of the dried crosslinked coating to a polyester
carrier film. In one embodiment, the matte release coat formulation
includes a primary crosslinking resin such as a melamine resin that
controls crosslinking and produces adhesion to the polyester
carrier film. A presently preferred crosslinking resin is
hexamethoxy methyl resin such as Cymel 303. A suitable primary
functional resin is a vinyl resin such as a medium molecular weight
vinyl chloride-vinyl acetate resin known as VAGH. The vinyl resin
can be present in an amount up to about 20% of the total solids in
the matte release coat. In addition, the matte release coat can
include a secondary functional resin to improve release of the top
surface of the decorative dry paint layer from the matte release
coat. In one embodiment, the secondary functional resin can be an
acrylic-modified alkyd resin such as the resin known as Chempol 13
1501 or Lankyd 13-1245. This secondary functional resin comprises
from about one percent to about 16% of the total solids, by weight,
of the matte release coat. The matte release coat further includes
a suitable catalyst for accelerating the crosslinking process,
typically comprising from about one percent to about eight percent
of the total solids in the matte release coat, by weight.
[0091] The resinous components of the matte release coat
composition are combined with suitable solvents. In one embodiment,
the resins are mixed with a primary resin solvent such as methyl
isobutyl ketone (MIBK) which comprises from about 65% to about 85%
of the total solvent in the formulation. A secondary resin solvent,
such as isopropyl alcohol (IPOH), is useful in retarding
crosslinking of resins in solution. The secondary resin solvent
preferably comprises from about 5% to about 20% of the total
solvent.
[0092] The matte release coat formulation is prepared by dissolving
the primary functional resin in the primary and secondary resin
solvents by mixing and then adding the secondary functional resin
together with a primary matting agent, preferably in the form of a
filler comprising a fine particulate inert inorganic material. In
one embodiment, the filler comprises aluminum silicate with an
average particle size of about 4.8 microns. In another embodiment,
the filler can comprise talc. The filler contained in the
formulation comprises up to about 50% of the total solids in the
matte release coat. In one embodiment, the talc filler material
comprises from about 40% to about 50% of the total solids contained
in the matte release coat. The fine particulate filler is
thoroughly dispersed in the resin and resin solvent blend,
preferably under elevated temperatures from about 100.degree. F. to
about 120.degree. F.
[0093] In use, when the matte release layer dries and cross links,
it forms a chemical matte coating on the surface of the carrier
sheet. The matte surface is controlled by the amount and particle
size of the filler. The fine particles project through the dried
exterior surface of the matte release coat to form, on a
microscopic scale, a surface with a microroughness that transfers a
replicated microroughness to the exposed surface of the dried outer
clear coat or dry paint layer. This produces light scattering,
resulting in a flat or low surface gloss matte finish on the top
surface of the decorative dry paint layer.
[0094] In one embodiment a matte release coat formulation useful
for this invention contains no significant amount of a
silicone-based release material and/or a wax-based component. Such
materials may be useful in providing release properties at high
temperatures; but the matte release coat of this invention, in one
embodiment, comprises a formulation that, in the absence of a
silicone-based release material or a wax-based component, provides
a useful combination of room temperature release, adherence of the
release liner to the dry paint layer, and transfer of the matte
surface to the exposed surface of the dry paint layer. Stated
another way, the matte release coat has a hardened state at room
temperature and is made from a resinous material that contains (1)
a surfacing component that forms a matte release surface, (2) an
adhesion component for releasably adhering the matte release
surface to the dry paint layer, and (3) a release component that
releases the matte release surface from contact with the dry paint
layer at room temperature to transfer the matte surface finish from
the matte release surface to the exposed surface of the dry paint
layer.
[0095] In one embodiment, the matte release coat comprises, on a
solids basis, from about 10% to about 30% by weight alkyd resin;
from about 10% to about 30% by weight vinyl resin; from about 20%
to about 35% by weight melamine crosslinking resin; and from about
5% to about 10% catalyst. The balance of the solids comprises the
fine particulate filler, e.g. talc, as described previously.
[0096] In one embodiment, the weight ratio of particulates to resin
or binder may range up to about 1.1:1, in one embodiment from about
0.7:1 to about 1.1:1, in another embodiment from about 0.7:1 to
about 0.9:1, and in a further embodiment from about 0.9:1 to about
1.1:1.
[0097] The gloss transferred to the outer surface of the dry paint
layer can be controlled by a combination of release coat
formulations and the composition of the outer surface layer of dry
paint in contact with the release coat. In one embodiment, an
85.degree. gloss of less than about 10 gloss units can be
transferred to dry paint films having a monocoat or base coat/clear
coat finish comprised of urethane, acrylic and/or vinyl resinous
paint layers. The preferred release coat comprises an acrylic/vinyl
blend containing a micro-particle filler. In another embodiment,
85.degree. gloss measurements of less than about 35 gloss units can
be transferred to dry paint films having a monocoat or base
coat/clear coat finish comprised of urethane, acrylic and/or vinyl
resinous paint layers. The preferred release coat comprises an
acrylic modified alkyd resin and/or vinyl resins containing
dispersed microparticles.
[0098] The carrier film or release liner is typically contained on
a supply roll from which the carrier is unwound and passed to a
gravure print station where the matte release coat is coated onto
the release liner. The release liner containing the matte release
coat is then passed through a drying oven operated at a temperature
from about 325.degree. F. to about 350.degree. F., sufficient for
drying and crosslinking the matte release coat. In the first stage
drying oven, the matte release coat is sufficiently cross-linked to
permanently bond it to the carrier sheet. Preferably, the matte
release coat is coated and dried to a coat weight (dry) from about
3 to about 6 gsm.
[0099] The adhesive release coat layer may comprise any release
coating composition known in the art. Silicone release coating
compositions may be used. The silicone release coating compositions
typically comprise polyorganosiloxanes such as
polydimethylsiloxanes. The silicone release coating composition
used in this invention 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). These compositions may also contain at
least one cure accelerator and/or adhesivity promoter.
[0100] Each of the layers in the multi-layer laminate may be
independently applied and dried and/or cured using known
techniques. The application techniques include gravure, reverse
gravure, offset gravure, roll coating, brushing, knife-over roll,
metering rod, reverse roll coating, doctor knife, dipping, die
coating, slot die coating, spraying, curtain coating, slide
coating, slide curtain coating, extrusion, co-extrusion,
flexographic, letter press, rotary screen, and flat screen. In one
embodiment, the pressure sensitive adhesive layer may be applied
using transfer lamination. The decorative print layers may be
applied using known printing techniques including gravure,
flexographic, silk screen, and ink jet printing. The applied layers
may be dried and/or cured by exposure to heat or to known forms of
ionizing or actinic non-ionizing radiation. Drying or curing
temperatures that may be used may range from about 115.degree. C.
to about 160.degree. C., and in one embodiment about 140.degree. C.
to about 150.degree. C. Useful types of radiation include
ultraviolet light and electron beam. The equipment for generating
these forms of thermal or radiation drying and/or curing are well
known to those skilled in the art.
[0101] Various layers of the multi-layer laminate also can be
formed by extrusion and co-extrusion techniques identified above
and described in more detail in U.S. application Ser. No. 457,826
identified above and incorporated herein by reference. The dry
paint layer or the support layer may be coextruded with the
adhesive layer using separate extruders as illustrated in FIG. 8 or
a dual die extruder as illustrated in FIG. 9. Referring to FIG. 8,
release liner 70 is uncoiled from a roll 72 and advanced past an
extrusion die 74 where it is coated with an adhesive layer 76, and
then past an extrusion die 78 where a reinforcing or support layer
79 is coated onto the adhesive layer 76. The resulting co-extrudate
is collected on a take-up roll 80. Referring to FIG. 9, the release
liner 70 is advanced past a dual extrusion die 82 which
simultaneously coats the release liner 70 with a coextruded
adhesive layer 84 and support layer 86. The resulting co-extrudate
is collected on a take-up roll 88.
[0102] The dry paint transfer laminate illustrated in FIG. 1 may be
made by applying the adhesive release coat to the lower surface of
the release liner using one of the foregoing application techniques
and then curing the release coat. The coat weight for the adhesive
release coat layer may be in the range from about 0.1 to about one
gram per square meter (gsm), and in one embodiment from about 0.25
to about 0.35 gsm. The matte release coat layer is then applied to
the upper surface of release liner using one of the above described
application techniques (e.g., gravure) and then dried or cured. The
coat weight for the matte release coat may be in the range from
about 2.5 to about 6.5 gsm, and in one embodiment, from about 4.5
to about 5.5 gsm. The liquid paint or coating composition for
forming the pigmented dry paint layer is then applied to the
surface of the matte release coat layer using one of the above
described application techniques (e.g., reverse roll or slot die)
and then dried or cured. The coat weight for the pigmented dry
paint layer may range from about 20 to about 60 gsm, and in one
embodiment about 30 to about 40 gsm. One or more coats may be
applied. The pressure-sensitive adhesive layer is then applied to
the upper surface of dry paint layer using one of the above
indicated application techniques (e.g., slot die) and then dried or
cured. The pressure sensitive adhesive may be applied using coating
techniques or transfer lamination. The coat weight for the pressure
sensitive adhesive layer may range from about 10 to about 30 gsm,
and in one embodiment about 11 to about 17 gsm. The dry paint
transfer laminate 20 may then be wound into roll form as
illustrated in FIG. 2.
[0103] The dry paint transfer laminate illustrated in FIG. 3 may be
made using the same procedure as the laminate 20 of FIG. 1, except
that the transparent outer clear coat layer is applied to the matte
release coat layer and then dried or cured prior to application of
the pigmented dry paint film layer. The dry paint layer is then
applied to the surface of the clear coat layer. The clear coat
layer may be applied using one of the foregoing application
techniques (e.g., gravure). The coat weight for the clear coat
layer may range from about one to about 5 gsm, and in one
embodiment about 2.5 to about 3.5 gsm. One or more coats may be
applied. The dry paint transfer laminate may then be wound into a
roll as illustrated in FIG. 2.
[0104] The dry paint transfer laminate illustrated in FIG. 4 may be
made using the same procedure used as the laminate 20, except that
the liquid paint composition for forming the printed decorative
layer is applied to the surface of the transparent film layer and
then cured prior to application of the dry paint film layer. The
dry paint film layer is then applied to the surface of the printed
decorative layer. The printed decorative layer may be applied using
any of the foregoing printing techniques (e.g., gravure,
flexographic, silk screen, or ink jet). The coat weight for the
printed decorative layer may range from about 0.3 to about 2 gsm,
and in one embodiment about 0.3 to about 0.7 gsm. The dry paint
transfer laminate may then be wound into a roll as illustrated in
FIG. 2.
[0105] The dry paint transfer laminate illustrated in FIG. 5 may be
made using the same procedure as the laminate of FIG. 4, except
that the liquid paint composition for forming the second printed
decorative layer is applied to the surface of the transparent film
layer and then dried or cured prior to the application of the first
printed decorative layer. The second printed decorative layer may
be applied using any of the foregoing printing techniques (e.g.,
gravure, flexographic, silk screen, ink jet). The coat weight for
the second printed decorative layer may range from about 0.3 to
about 2 gsm, and in one embodiment about 0.3 to about 0.7 gsm. The
dry paint transfer laminate may then be wound into a roll as
illustrated in FIG. 2.
[0106] The dry paint transfer laminate illustrated in FIG. 6 may be
made using the same procedure used for making the laminate 20
illustrated in FIG. 1, except that the reinforcing layer is adhered
to the dry paint layer. The reinforcing layer may be coextruded
with the adhesive layer and then the dry paint film layer may be
coated (e.g., gravure) onto the reinforcing layer. The dry paint
transfer laminate may then be wound into a roll as illustrated in
FIG. 2.
[0107] The dry paint transfer laminate illustrated in FIG. 7 may be
made using the same procedure used for making the laminate 20
illustrated in FIG. 1, except that the barrier layer is coated on
the dry paint transfer layer. The dry paint transfer laminate may
then be wound into a roll as illustrated in FIG. 2.
[0108] The dry paint transfer laminate may be made in a single
production line or in multiple production lines or multiple
production facilities. With multiple production lines or
facilities, part of the laminate may be produced as a roll
laminate, dried or cured, rolled up, transferred to the next
production line or facility, unrolled, and further treated with the
application of additional layers. For example, the dry paint layer
and the adhesive layer may be formed in multiple lines, or they may
be formed in sequence in a single production line, or they may be
simultaneously formed such as by coextrusion or multi-die coating
methods.
[0109] The dry paint transfer laminate 20 may be used by unrolling
the laminate from the roll illustrated in FIG. 2, and
simultaneously applying the laminate to the substrate surface to be
covered. The substrate may comprise any flat surface. The flat
surface may comprise wall board, plastic sheet, metal sheet,
composites, and the like. The substrate may comprise an interior
(i.e., indoor) surface or an exterior (i.e., outdoor) surface. The
laminate may be applied to a painted surface having various surface
finishes, from flat, semi-gloss to glossy. The laminate is placed
over the substrate with the adhesive layer in contact with the
substrate. Pressure is applied, with repositioning if necessary,
until the laminate is adhered to the surface. The release liner is
then peeled off the front face of the decorative laminate, leaving
the dry paint film layer adhered to the substrate by the adhesive
layer. The dry paint transfer laminates shown in FIGS. 3 through 7
and in FIG. 10 also may be applied to a substrate surface in the
same manner as the laminate 20.
Differential Release System
[0110] In one embodiment of the invention, the release properties
of the laminate are controlled so that, in the embodiments
illustrated in FIGS. 1-7 and FIG. 10, the release force required to
separate the matte release coat layer from the dry paint layer
(which may comprise the transparent layer, the color layer, or
printed decorative layer) is greater than the release force
required to separate the adhesive release coat layer from the
pressure-sensitive adhesive layer.
[0111] In one embodiment, the carrier release force required to
separate the matte release coat layer from the dry paint layer
(i.e., the color layer, the clear coat layer, or the printed
decorative layer) may be generally in the range from about 20 to
about 180 grams per two inches (g/2 in), in one embodiment from 30
to about 150 g/2 in, and in another embodiment 40 to about 120 g/2
in. In other embodiments the release force range may be from 50 to
about 100 g/2 in, from 50 to about 90 g/2 in, from about 70 to
about 90 g/2 in, and from about 50 to about 65 g/2 in.
[0112] In one embodiment, the unwind release force required to
separate the adhesive release coat layer from the
pressure-sensitive adhesive layer is generally in the range from
about 10 to about 150 g/2 in, in one embodiment from about 20 to
about 150 g/2 in, in another embodiment about 20 to about 90 g/2
in, and in other embodiments from about 30 to about 150 g/2 in,
about 30 to about 100 g/2 in, and about 30 to about 70 g/2 in.
[0113] The test method for determining these release forces
involves measuring the force required to separate a two-inch wide
release coated liner from the dry paint layer or from an adhesive
coated substrate, with the release coated liner extending at an
angle of 90.degree. relative to the layer or substrate and being
pulled at a rate of 300 inches per minute. The test is conducted at
room temperature.
[0114] According to one embodiment of the invention, the decorative
film contains a differential release system which enables the film
to be unrolled from its self-wound form with the release liner
maintaining continuous contact with the dry paint layer. As the
decorative film is unrolled, the silicone-coated outer surface of
the release liner preferentially releases from contact with the PSA
side of the film while the matte release coat side of the release
liner maintains constant contact with the dry paint layer. This
contact of the release liner with the dry paint layer is maintained
throughout unwinding, application to the substrate surface, and any
repositioning of the decorative film on the surface, until the
release liner is ready to be peeled away from the decorative paint
layer. The differential release system is adapted to maintain such
preferential contact between the release liner and the dry paint
layer because the dry paint layer is non-self-supporting, i.e., it
has no structural integrity in and of itself, and therefore relies
upon its contact with the release liner to provide the necessary
structural support during unrolling, handling and repositioning,
for example.
[0115] As mentioned previously, the release force between the
release liner and the matte release layer (carrier release force)
exceeds the release force between the silicone-coated side of the
releaser liner and the PSA (unwind release force). Tests have shown
that this "force differential" is dependent upon the rate or speed
at which the materials at each interface are peeled away from each
other. Inasmuch as the self-wound film, in use, may be unwound at
different speeds, an objective of the differential release system
is to ensure that the carrier release force exceeds the unwind
release force over a wide range of release rates that are normally
encountered during use. Generally speaking, this force differential
is maintained over a wide range of speeds. During use, slow rates
are encountered when unwinding a new roll or during the initial
start of a roll on the surface. Medium to fast rates are
encountered when the strip continues down the surface. In one
embodiment, the force differential is maintained for a range of
speeds up to about 300 inches per minute for a 2 inch wide strip.
In another embodiment, this force differential is maintained up to
a speed of at least 600 inches per minute for a 2 inch wide
strip.
[0116] The force needed to remove the PSA from the silicone side of
the liner also should be less than the force needed to peel the
carrier off the dry paint side in order to prevent peeling the
carrier during slitting or unwinding, in addition to avoiding
peeling of the carrier during unrolling, application to a surface,
and repositioning on the surface. Unwind speeds in excess of 600
inches per minute may be encountered when cutting the film to
individual roll sizes, but tests have shown that, in one
embodiment, at such high speeds an undesired unwind response is not
produced even when unwind release forces exceed carrier release
force.
[0117] Such differential release forces can be measured, as
described previously, by separating the liner from the matte
release layer or the PSA layer in a two-inch wide strip at an angle
of 90.degree. pulled at a rate of 300 inches per minute with the
tests conducted at room temperature. In one embodiment, the carrier
release force is maintained higher than the unwind release force
for release rates from about 6 inches per minute up to at least
about 300 inches per minute. In another embodiment, the carrier
release force is maintained within a range from about 45 to about
65 grams/2 inches over a wide range of release rates from about 6
inches per minute up to at least about 300 inches per minute. A
corresponding unwind release force is maintained within a range
from about 20 to about 40 grams/2 inches, over a range of liner
release rates from about 12 to about 60 inches per minute.
[0118] Tests have shown that carrier release forces are maintained
at a relatively uniform level across a wide range of release rates,
whereas unwind release forces tend to increase as release rates
increase and can eventually exceed the carrier release forces above
certain higher release rate levels. However, tests have shown that
for release rates above about 300 inches per minute, an unwind
release force in excess of the carrier release force does not
negatively impact premature release of the release liner from the
matte release layer during normal use conditions of the self-wound
decorative film.
[0119] The composition of the PSA is coordinated with the
composition of the dry paint layer in order to produce the desired
differential release properties. The particular formulation used
for the PSA can affect unwind release response. In addition, the
composition of the dry paint layer which comes into contact with
the matte release layer can affect release properties. In one
embodiment, a relatively low unwind release force can be desirable
if the carrier release force is relatively higher. However, there
are limitations on the absolute magnitude of the carrier release
force. Producing a substantially higher carrier release force
compared to the lower unwind release force can maintain desired
contact between the carrier and dry paint film during unwinding and
application to a substrate surface; but if the carrier release
force is too high, there may be difficulties in producing a proper
release of the release liner from the dry paint layer after the PSA
side of the laminate has been affixed to the substrate surface. If
the carrier release force is too high, the user may experience
difficulty in initially peeling the liner from the paint film; or
removing the release liner may overcome the bond between the dry
paint layer and the substrate and result in peeling the dry paint
layer from the surface.
[0120] Therefore, another objective of the invention is to produce
a differential release system in which the carrier release force is
higher than the unwind release force over a broad range of release
rates, but the carrier release force level is maintained below a
certain maximum force level. In one embodiment, a preferred dry
paint layer comprises a transparent outer clear coat layer as
described in Examples 7 and 9, in which the outer layer comprises a
solvent-cast acrylic resinous material. This top coat material
provides benefits of abrasion and stain resistance and
repaintability in the finished film in addition to a useful carrier
release force level when the matte release liner is peeled from the
outer layer. The composition of the matte release coat in this
embodiment comprises the alkyd/vinyl/melamine resinous composition
of Examples 7 or 9, and the composition of the PSA comprises the
adhesive formulation of Examples 7 or 9. In this embodiment, the
carrier release force when peeled from the acrylic-based paint
layer is maintained within a range of about 45 to about 65 grams
per 2 inches. Corresponding unwind release force is maintained
within a range of about 20 to about 40 grams per 2 inches, over a
range of liner release rates from about 12 to at least about 60
inches per minute. It has been observed that the lower carrier
release force level associated with the acrylic-based outer clear
coat layer, i.e., below about 65 grams per 2 inches, provides
sufficiently low carrier release properties to enable users to
easily remove the release liner over a wide range of use conditions
and carrier release rates.
[0121] By lowering the unwind release force response, the carrier
release force then can be lowered to a more desirable level as
mentioned previously. The PSA used in the present invention is
preferably an internally cross-linked pressure-sensitive adhesive
which lowers peel and tack levels. In one embodiment, the
internally cross-linked acrylate-based copolymer emulsion PSA of
Example 9, for instance, produces unwind release levels that are
sufficiently low to allow use of matte release coatings that
produce carrier release responses at the more desirable lower
levels as described previously. Use of a non-crosslinked (or
lightly crosslinked) pressure-sensitive adhesive, which is softer,
can have undesirable edge ooze characteristics during use; but in
addition, it can produce higher peel and tack levels that
undesirably increase the unwind release force in a direction toward
the carrier release force.
[0122] The matte release coat composition also can control the
carrier release force level. In the matte release coat formulation
of Examples 7 and 9, the melamine crosslinking agent can be used to
control the carrier release force level. The content of the alkyd
resin and the lower molecular weight vinyl resin also can be
controlled to lower release force. A useful combination of these
components can produce desired room temperature adhesion to the
release liner and release force response when peeling the release
liner from the dry paint layer surface. The release coat
composition also controls uniformity of and gloss level of the
transferred matte surface.
[0123] As mentioned, the tack or peel level of the PSA also is
controlled with respect to the surface to which the laminate is
affixed. That is, the PSA in its dry form must have a low unwind
release force from the silicone-coated release liner but also must
have a sufficient level of tack to properly adhere to a substrate
surface as well as providing sufficient repositionability.
[0124] A pressure sensitive adhesive useful for this invention is
characterized by relatively low tack and peel force levels and
relatively low room temperature flow properties. Such adhesives, if
they are too soft, can undesirably increase unwind force and can
adversely affect repositioning of the paint film. Acrylic emulsion
PSAs are particularly useful when such PSAs have a level of
crosslinking that produces an adhesive material with a relatively
high cohesive strength that yields a desirable combination of low
tack, peel and flow properties. Examples of useful PSAs in which
the level of crosslinking can be appropriately adjusted include
acrylic emulsion PSAs such as pure polymer (butyl acrylate or
2-ethyl hexyl acrylate or 2-ethyl hexyl acrylate/butyl acrylate)
PSAs or similar pigmented polymer and copolymer materials.
[0125] A particularly useful PSA for this invention is an
internally cross-linked acrylic emulsion PSA such as a
non-tackified cross-linked copolymer emulsion of butyl acrylate and
2-ethyl hexyl acrylate. This particular adhesive contains a
crosslinking agent which controls the level of crosslinking and
produces a desirable combination of low tack, peel and flow and
relatively high cohesive strength at a useful low coat weight. This
adhesive is available from Avery Dennison Corporation as product
no. S-3506, or in its pigmented form as product no. S-3526.
[0126] Other multi-functional acrylic-based polymer and copolymer
materials can be used to produce similar adhesive properties in
their cross-linked form. In addition, other suitable
pressure-sensitive adhesives for this invention can comprise high
molecular weight acrylic emulsion adhesives. Such high molecular
weight adhesives can behave in a manner similar to the cross-linked
adhesives in producing low tack, peel and flow characteristics at
sufficiently high cohesive strength. Exterior crosslinking agents
also can be used to provide the desired level of crosslinking in
such pressure sensitive adhesives materials.
[0127] Another useful adhesive is a high molecular weight
cross-linked acrylic emulsion adhesive (butyl acrylate/2-ethyl
hexyl acrylate) available from Avery Dennison as product no.
S-3000.
[0128] As mentioned previously, the PSA useful for this invention
can be characterized, in part, as an adhesive that produces an
unwind release force which is lower than the carrier release force,
when releasing from contact with a silicone-coated release liner.
The PSA also can be characterized, in part, by its level of
adhesion to a substrate such as flat paint, glossy paint, primed
drywall or stainless steel, for example. In one embodiment, the PSA
formulation can be controlled to produce a low level of tack
characterized by a looptack value within the range of about 0.8 to
about 2.4 lbs/in, in which the adhesive is measured for adhesion to
stainless steel and laminated to a 2 mil PET facestock, at a
standard coat weight of 15 gsm.
[0129] In another embodiment, the PSA formulation can be controlled
to produce a low level of 90.degree. peel force adhesion,
characterized by 15 minute peel adhesion to stainless steel in the
range of 0.80 to 1.5 lbs/in for 2 mil PET; or 15 minute peel
adhesion to flat painted surfaces of 0.05 to 0.30 lbs/in, or 15
minute peel adhesion to glossy painted surfaces of 0.20 to 0.40
lbs/in in which the adhesive is laminated to the dry paint transfer
film with the release liner carrier.
[0130] In another embodiment, the PSA can be adjusted to produce a
low peel force characterized by 90.degree. peel adhesion values at
24 hours as follows: dry wall--0.30 to 0.50 lbs/in; flat
paint--0.40 to 0.65 lbs/in; and glossy paint--0.60 to 0.90
lbs/in.
[0131] The PSA also can be characterized by its desired low flow
properties at room temperature. Such characteristics can be
measured by its WPI (plasticity) value which in one embodiment has
a WPI value from about 3.2 to about 3.8 mm.
[0132] The desired PSA also has a sufficient level of cohesive
strength that enables the adhesive to permanently bond the paint
film to the wall in the absence of a high level of tack. The level
of crosslinking can effect such a cohesive strength, and in one
embodiment, the cohesive strength is measured by a shear value of
greater than 1,000 minutes (500 g 1/4 sq. in., 20 minute dwell,
14-16' gsm coat weight direct coated on 2 mil PET dried at
120.degree. C. for 5 minutes).
EXAMPLES 1 AND 2
[0133] A polyethylene terephthalate (PET) release liner is coated
on one side with a silicone release coating corresponding to the
adhesive release coating layer. The thickness of the release coated
liner is 0.92 mil, also known as Mitsubishi 92 gauge SLK.
[0134] A matte release coat is applied to the other side of the
release liner using gravure at a coat weight of 6.5-7.75 gsm. The
formulation for the matte release coat is as follows: 26 parts by
weight methylisobutyl ketone, 6 parts by weight isopropanol, 34.8
parts by weight Lankyd 13-1425 (a product supplied by Akzo Resins
identified as an acrylic modified alkyd), 2.6 parts by weight
Elvacite 2042 (a product supplied by Lucite International
identified as a polyethyl methacrylate polymer), 30 parts by weight
Microtalc MP 15-38 (a product supplied by Barretts Minerals
identified as a talc extender pigment), 2.5 parts by weight Cycat
4040 (a product supplied by Cytec identified as paratoluene
sulfonic acid), and 8.7 parts by weight Cymel 303 (a product
supplied by Cytec identified as a melamine resin). The matte
release coat is dried using forced hot air at a temperature of
149.degree. C. which crosslinks the resin and bonds the matte
silicone coat to the polyester carrier. The talc particles project
from the surface of the dried matte release coat to form a
microroughened surface.
[0135] A transparent clear coat layer is applied to the matte
release coat using gravure at a coat weight of 2.7-2.9 gsm and
dried using forced hot air at a temperature of 120.degree. C. The
formulation for the clear coat layer is as follows: 46.7% by weight
methyl ethyl ketone, 31.3% by weight toluene, 11% by weight VYNS (a
product of Union Carbide identified as a vinyl chloride/vinyl
acetate copolymer containing 5-20% by weight vinyl acetate), and
11% by weight Vitel 2200B (a product of Bostic identified as a
polyester copolymer).
[0136] The following paint compositions are used to form a dry
paint layer on the clear coat layer, one for Example 1 and the
other for Example 2. The dry paint layer of Example 1 has a deep
brown tone, while the dry paint layer of Example 2 has an orange
pastel tone. In the following table, all numerical values are in
parts by weight. TABLE-US-00002 Component Example 1 Example 2
Methylethyl ketone 66.7 66.7 Toluene 33.3 33.3 VYHH (product of
Union Carbide 50.05 30.55 identified as a vinyl chloride/vinyl
acetate copolymer) Edenol 9790 (a product of Cognis 24.65 15.05
identified as a polyester plasticizer) Yellow pigment 42 (iron
oxide) 17.8 2.3 Orange pigment 36 (monoazo 2.5 0.38
benzimidazoline) Black 7 (carbon black) 0.1 0.02 White 6 (titanium
dioxide) 4.9 51.7
[0137] The pigment-to-binder volume ratio for Example 1 is 10%, and
for Example 2 the ratio is 27%. The above paint formulations are
applied to the clear coat layer using a reverse roll coater and are
dried at a temperature of 135.degree. C. to drive off the solvents.
The dry film thickness of each of the dry paint layers is 0.7
mil.
[0138] A pigmented pressure sensitive adhesive is then applied to
the dry paint layer at a coat weight of 14-20 gsm using transfer
lamination to provide an adhesive layer corresponding to pressure
sensitive adhesive layer 120. The adhesive is an ethyl hexyl
acrylate based PSA available from Avery Dennison Corporation under
product no. S-692N and the formulation for the pressure sensitive
adhesive is as follows: 70-90% by weight 2-ethyl hexyl acrylate,
1-10% by weight acrylic acid, 10-20% by weight methyl acrylate,
3.7% UCD 1106E (a product of Rohm and Haas identified as a titanium
dioxide dispersion concentrate), and 0.3% by weight of UCD 1507E (a
product of Rohm and Haas identified as a carbon black dispersion
concentrate).
EXAMPLE 3
[0139] The procedure used for Examples 1 and 2 is repeated except
that the following liquid paint composition is used to form the dry
paint layer. In the following table, all numerical values are in
parts by weight. TABLE-US-00003 Component Parts Methylethyl ketone
29.6 Toluene 19.5 Vitel 2200 B 11.6 Vitel 2650 (product of Bostic
identified 11.5 as a polyester copolymer) R-900 (product of DuPont
identified as 27.5 titanium dioxide) 955-39230 (product of
Gibraltar Chemical 0.2 Works identified as shading black) 99-34520
(product of Gibraltar Chemical 0.1 Works identified as phthalo blue
GS) 955-37470 (product of Gibraltar Chemical tint Works identified
as carbazole violet)
[0140] The foregoing paint composition has a light blue color. The
dry film thickness of the dry paint film layer is 0.6-0.8 mil.
EXAMPLE 4
[0141] A PET release liner is coated on one side with a silicone
release coating corresponding to the adhesive release coat layer.
The thickness of the release coated liner is 0.92 mil.
[0142] A matte release coat layer is applied to the other side of
the release liner using gravure at a coat weight of 4.4-4.6 gsm.
The formulation for the matte release coat is as follows: 50.54
parts by weight methylisobutyl ketone, 7.84 parts by weight
isopropanol, 8.93 parts by weight Lankyd 13-1425, 10.68 parts by
weight VAGH (product of Union Carbide identified as hydroxy
modified polyvinyl chloride/polyvinyl acetate copolymer), 22 parts
by weight Microtalc MP 15-38, 2 parts by weight Cycat 4040, and 6.8
parts by weight Cymel 303. The matte release coat is dried using
forced hot air at a temperature of 149.degree. C.
[0143] A first coat of a transparent outer clear coat layer is
applied to the matte release coat using gravure at a coat weight of
1.3-2 gsm and dried using forced hot air at a temperature of
120.degree. C. The dry film thickness is 0.05-0.1 mil. The
formulation for this first clear coat layer is as follows: 41.5% by
weight methyl ethyl ketone, 41.5% by weight methyl isobutyl ketone,
and 17% by weight Elvacite 2042 (a product of Lucite International
identified as a polymethyl methacrylate).
[0144] A second coat of a clear coat layer is applied over the
first transparent layer using gravure at a coat weight of 1.0-1.5
gsm and dried using forced hot air at a temperature of 120.degree.
C. The dry film thickness is 0.03-0.1 mil. The formulation for this
second transparent film layer coat is as follows: 41.5% by weight
methyl ethyl ketone, 41.5% by weight methyl isobutyl ketone, and
17% by weight VYHH (a product of Union Carbide identified as a
vinyl chloride/vinyl acetate copolymer containing 5-20% by weight
vinyl acetate).
[0145] A decorative print layer is printed over the second
transparent clear coat layer at a coat weight of 3.0-3.2 gsm and
dried in hot air at a temperature of 120.degree. C. The paint
composition for this decorative print layer has the following
formulation (all numerical values are in parts by weight):
TABLE-US-00004 Component Parts Methylethyl ketone 42.6 Methyl
isobutyl ketone 38.7 VYHH 15.86 DP 80110 (product of Gibraltar
Chemical 2.1 Works identified as containing methylethyl ketone,
toluene, carbon black and acrylic polymer) DP 36640 (product of
Gibraltar Chemical 0.22 Works identified as containing methyl ethyl
ketone, toluene, quinacridone red, and acrylic polymer) I8977
(product of Gibraltar Chemical 0.10 Works identified as containing
methyl ethyl ketone, toluene, R.S. Phthalo Blue, and acrylic
polymer) I8980 (product of Gibraltar Chemical 0.38 Works identified
as containing methyl ethyl ketone, toluene, isoindolinone yellow
and acrylic polymer)
[0146] An additional decorative print layer is printed over the
previous decorative print layer at a coat weight of 0.8 gsm and
dried in hot air at a temperature of 120.degree. C. The paint
composition used for this decorative print layer has the following
formulation (all numerical values are in parts by weight):
TABLE-US-00005 Component Parts Methylethyl ketone 42.85 Methyl
isobutyl ketone 39.1 VYHH 16.0 DP 80110 1.71 DP 36640 0.18 18977
0.18
[0147] The following paint composition is coated over the two dried
print coat layers at a coat weight of 30-32 gsm and dried in hot
air at a temperature of 120.degree. C. to provide a dry paint. In
the following table, all numerical values are in parts by weight.
TABLE-US-00006 Component Parts Methyl ethyl ketone 34 Toluene 16.7
VYHH 18.3 Edenol 9790 9 AVI-0301-3 Orange (product of Gibraltar 8.9
Chemical Works identified as containing methyl ethyl ketone,
toluene, diarylide orange, VYHH and Edenol 9790) AVI-0301-5 Magenta
(product of Gibraltar 5.3 Chemical Works identified as containing
methyl ethyl ketone, toluene, Metal Azo Red, VYHH and Edenol 9790)
AVI-0301-6 Iron Red (product of Gibraltar 3.7 Chemical Works
identified as containing methyl ethyl ketone, toluene, Iron Oxide
Red, VYHH and Edenol 9790) AVI-0301-1 TiO.sub.2 White (product of
Gibraltar 3.52 Chemical Works identified as containing methyl ethyl
ketone, toluene, titanium dioxide, VYHH and Edenol 9790) AVI-0301-2
Carbon Black (product of 0.03 Gibraltar Chemical Works identified
as containing methyl ethyl ketone, toluene, carbon black, VYHH and
Edenol 9790)
[0148] A pigmented pressure sensitive adhesive is then applied over
the dry paint layer at a coat weight of 17 gsm using transfer
lamination to provide an adhesive layer corresponding to pressure
sensitive adhesive layer. The formulation for the pressure
sensitive adhesive is as follows: 96% by weight of a non-tackified
acrylic emulsion containing a cross-linked copolymer of butyl
acrylate and 2-ethyl hexyl acrylate, 3.7% by weight UCD 1106E, and
0.3% by weight UCD 1507E.
EXAMPLE 5
[0149] A PET release liner is coated on one side with a silicone
release coating. The thickness of the release coated liner is 0.92
mil.
[0150] A matte release coat is applied to the other side of the
release liner using gravure at a coat weight of 4.4-4.6 gsm. The
matte release coat is dried using forced hot air at a temperature
of 149.degree. C. The formulation for the matte release coat is as
follows (all numerical values are in parts by weight):
TABLE-US-00007 Component Parts Methyl isobutyl ketone 52.54
Elvacite 4402 (product of Lucite 20.98 International identified as
hydroxy ethyl methacrylate modified acrylic resin) VYNS 1.35
Microtalc 15-38 22.85 Byk 451 (product supplied by Byk 2.2 Chemie
identified as blocked acid catalyst) Cymel 303 6.38
[0151] A transparent clear coat layer is applied to the matte
release coat using a reverse roll coater at a coat weight of 13 gsm
and dried using forced hot air at a temperature of 120.degree. C.
The dry film thickness is 0.4 mil. The formulation for the
transparent clear coat layer is as follows (all numerical values
are in parts by weight): TABLE-US-00008 Component Parts Rucothane
CO-A-5002L (product 62.5 of Ruco Chemical identified as polyester
urethane) Toluene 18.75 Isopropanol 18.75
[0152] A decorative print layer is printed over the above indicated
transparent film layer at a coat weight of 1 gsm and dried in hot
air at a temperature of 120.degree. C. The paint composition used
for this decorative layer has the following formulation (all
numerical values are in parts by weight): TABLE-US-00009 Component
Parts Methyl ethyl ketone 25.67 Methyl isobutyl ketone 22.0 VYHH
9.17 I8980 3.5 DP 37251 (product of Gibraltar Chemical 0.99 Works
identified as containing perylene red, methyl ethyl ketone, toluene
and acrylic polymer) DP80110 1.0 DP39600 (product of Gibraltar
Chemical 37.47 Works identified as containing TiO.sub.2, methyl
ethyl ketone, toluene and acrylic polymer) I8977 0.20
[0153] The following paint composition is coated over the
decorative print layer at a coat weight of 66 gsm and dried in hot
air at a temperature of 138.degree. C. to form a dry paint layer.
In the following table, all numerical values are in parts by
weight: TABLE-US-00010 Component Parts Methyl isobutyl ketone 24.11
Toluene 20.65 VYHH 11.54 R-900 38.4 Acryloid B-72 (product of Rohm
and 3.86 Haas identified as an acrylic resin) I8980 2.6 DP37251
0.21 DP80110 0.40
[0154] A pressure sensitive adhesive is then applied over the dry
paint layer at a coat weight of 15-20 gsm using transfer lamination
to provide an adhesive layer. The pressure sensitive adhesive is a
non-tackified acrylic emulsion. The formulation for the pressure
sensitive adhesive is as follows: 70-90% by weight 2-ethyl hexyl
acrylate, 1-10% by weight acrylic acid, and 10-20% by weight methyl
acrylate.
EXAMPLE 6
[0155] A PET release liner is coated on one side with a silicone
release coating. The thickness of the release coated liner is 0.92
mil.
[0156] A matte release coat is applied to the other side of the
release liner using gravure. The release coat is dried using forced
hot air at a temperature of 148.9.degree. C. The matte release coat
is applied at a coat weight of 4.0-5.0 gsm. The formulation for the
matte release coat is as follows (all numerical values are in parts
by weight): TABLE-US-00011 Component Parts Methyl isobutyl ketone
42.03 Isopropanol 8.51 Microtalc 15-38 23.87 Cymel 303 7.36 Cycat
4040 1.8 VROH (product supplied by 16.43 Union Carbide identified
as a vinyl chloride/vinyl acetate copolymer with OH
functionality)
[0157] A transparent clear coat layer is applied over the matte
release coat using a 2 mil byrd bar at a coat weight of 30 gsm and
dried using hot air at a temperature of 126.7.degree. C. The
formulation for the transparent film layer is as follows (all
numerical values are in parts by weight): TABLE-US-00012 Component
Parts Water 7.98 N-methyl pyrrolidone 4.79 Texanol (product of
Eastman 4.79 Chemicals identified as an ester alcohol) BYK 333
(product of Byk Chemie 0.4 identified as a wetting agent) Vycar 351
(product of Noveon identified 79.81 as a polyvinyl chloride
copolymer emulsion) Antifoam PD-218 (product of Magrabar 0.32
Chemical identified as an antifoam agent) Rheolate 350 (product of
heox, Inc. 1.92 identified as a thickener)
[0158] The following paint composition is coated over the
transparent clear coat film at a coat weight of 96 gsm and dried in
hot air at a temperature of 126.7.degree. C. to form a dry paint
film layer. In the following table, all numerical values are in
parts by weight: TABLE-US-00013 Component Parts Water 18.28
Surfynol CT-324 (product of Air 0.98 Products identified as a
surfactant) R-900 32.88 Vycar 460X45 (product of Noveon identified
34.72 as a vinyl chloride/acrylic copolymer) Vycar 460X46 (product
of Noveon identified 11.57 as a vinyl chloride/acrylic copolymer)
Antifoam PD-218 0.19 Byk 333 0.23 Rheolate 350 1.2
[0159] A pressure sensitive adhesive layer is then applied over the
dry paint layer at a coat weight of 17 gsm using transfer
lamination to provide an adhesive layer corresponding to pressure
sensitive adhesive layer. The formulation for the pressure
sensitive adhesive is as follows: 96% by weight of a non-tackified
emulsion containing a cross-linked copolymer of butyl acrylate and
2-ethyl hexyl acrylate, 3.7% by weight UCD 1106E, and 0.3% by
weight UCD 1507E.
EXAMPLE 7
[0160] A PET release liner is coated on one side with a silicone
release coat layer. The thickness of the release coated liner is
0.92 mil.
[0161] A matte release coat is applied to the other side of the
release liner using gravure at a coat weight of 4.4-4.6 gsm. The
formulation for the matte release coat is as follows: 50.54 parts
by weight methyl isobutyl ketone, 7.84 parts by weight isopropanol,
8.93 parts by weight Lankyd 13-1425, 10.68 parts by weight VAGH
(product of Union Carbide identified as hydroxy modified polyvinyl
chloride/polyvinyl acetate copolymer), 22 parts by weight Microtalc
MP 15-38, 2 parts by weight Cycat 4040, and 6.8 parts by weight
Cymel 303. The matte release coat is dried using forced hot air at
a temperature of 149.degree. C.
[0162] A transparent clear coat layer is applied to the matte
release coat using gravure at a coat weight of 12-16 gsm and dried
using forced hot air at a temperature of 165.degree. C. The dry
film thickness is 0.35-0.5 mil. The formulation for this
transparent film layer is as follows (all numerical values are in
parts by weight): TABLE-US-00014 Component Parts Cyclohexanone 69.3
Elvacite 2042 10.5 Solsperse 17000 (product of Avecia 0.1
identified as a wetting agent) Tinuvin 234 (product of Ciba
identified 0.6 as a light stabilizer) Kynar 301F (product of
Atofina 27.0 identified as a polyvinyl fluoride homopolymer)
N-methyl-2-pyrrolidone 2.5
[0163] A decorative print layer is printed over the transparent
coating layer at a coat weight of 0.3-1.2 gsm and dried in hot air
at a temperature of 105.degree. C. The paint composition used for
this decorative layer has the following formulation (all numerical
values are in parts by weight): TABLE-US-00015 Component Parts
Methylethyl ketone 36.0 Methyl propyl ketone 35.1 Kynar 7201 (SL)
(product of Atofina 10.2 identified as a polyvinyl fluoride
copolymer) Elvacite 2010 (product of Lucite 3.4 International
identified as a polymethyl methacrylate) Tinuvin 234 0.27 DP35740
(product of Gibraltar 0.10 Chemical Works identified as a buff
mixed metal oxide pigment concentrate) DP35820 (product of
Gibraltar 11.7 Chemical Works identified as a brown mixed metal
oxide pigment concentrate) DP39040 (product of Gibraltar 3.3
Chemical Works identified as a black mixed metal oxide pigment
concentrate)
[0164] An additional decorative print layer is printed over the
previous printed decorative layer at a coat weight of 0.3-1.2 gsm
and dried in hot air at a temperature of 105.degree. C. The paint
composition used for this decorative print layer has the following
formulation (all numerical values are in parts by weight):
TABLE-US-00016 Component Parts Methylethyl ketone 34.0 Methyl
propyl ketone 33.0 Kynar 7201 (SL) 9.6 Elvacite 2010 3.2 Tinuvin
234 0.25 DP35740 14.4 DP35820 5.0 DP39040 3.2
[0165] The following paint composition is coated over the
decorative print layers at a coat weight of 6-10 gsm and dried in
hot air at a temperature of 105.degree. C. to provide a dry paint
film layer corresponding to dry paint film layer 110. In the
following table, all numerical values are in parts by weight.
TABLE-US-00017 Component Parts Methyl ethyl ketone 27.6 Methyl
propyl ketone 26.3 Kynar 7201 (SL) 7.4 Elvacite 2010 2.5 Tinuvin
234 0.2 DP35740 4.1 DP35820 7.8 DP39040 0.6 DP39600 (product of
Gibraltar 23.6 Chemical Works identified as a white titanium
dioxide pigment concentrate)
[0166] A pigmented pressure sensitive adhesive is then applied over
the dry paint layer at a coat weight of 17 gsm using transfer
lamination to provide an adhesive layer corresponding to pressure
sensitive adhesive layer 120. The formulation for the pressure
sensitive adhesive is as follows: 96% by weight of a non-tackified
acrylic emulsion containing a cross-linked copolymer of butyl
acrylate and ethyl hexyl acrylate, 3.7% by weight UCD 1106E, and
0.3% by weight UCD 1507E.
EXAMPLE 8
[0167] A PET release liner is coated on one side with a silicone
release coating corresponding to the adhesive release coat layer.
The thickness of the release coated liner is 0.92 mil.
[0168] A matte release coat is applied to the other side of the
release liner using gravure at a coat weight of 4.4-4.6 gsm. The
formulation for the matte release coat is as follows: 50.54 parts
by weight methylisobutyl ketone, 7.84 parts by weight isopropanol,
8.93 parts by weight Lankyd 13-1425, 10.68 parts by weight VAGH
(product of Union Carbide identified as hydroxy modified polyvinyl
chloride/polyvinyl acetate copolymer), 22 parts by weight Microtalc
MP 15-38, 2 parts by weight Cycat 4040, and 6.8 parts by weight
Cymel 303. The matte release coat is dried using forced hot air at
a temperature of 149.degree. C.
[0169] A decorative print layer is printed over the matte release
coat at a coat weight of 0.3-1.2 gsm and dried in hot air at a
temperature of 105.degree. C. The paint composition used for this
decorative layer has the following formulation (all numerical
values are in parts by weight): TABLE-US-00018 Component Parts
Methylethyl ketone 36.0 Methyl propyl ketone 35.1 Kynar 7201 (SL)
(product of Atofina 10.2 identified as a polyvinyl fluoride
copolymer) Elvacite 2010 (product of Lucite 3.4 International
identified as a polymethyl methacrylate) Tinuvin 234 0.27 DP35740
(product of Gibraltar 0.10 Chemical Works identified as a buff
mixed metal oxide pigment concentrate) DP35820 (product of
Gibraltar 11.7 Chemical Works identified as a brown mixed metal
oxide pigment concentrate) DP39040 (product of Gibraltar 3.3
Chemical Works identified as a black mixed metal oxide pigment
concentrate)
[0170] An additional decorative print layer is printed over the
previous printed decorative layer at a coat weight of 0.3-1.2 gsm
and dried in hot air at a temperature of 105.degree. C. The paint
composition used for this decorative print layer has the following
formulation (all numerical values are in parts by weight):
TABLE-US-00019 Component Parts Methylethyl ketone 34.0 Methyl
propyl ketone 33.0 Kynar 7201 (SL) 9.6 Elvacite 2010 3.2 Tinuvin
234 0.25 DP35740 14.4 DP35820 5.0
[0171] The following paint composition is coated using rotogravure
over the decorative print layers at a coat weight of 5-16 gsm and
dried in hot air at a temperature of 105.degree. C. to form a dry
paint layer. In the following table, all numerical values are in
parts by weight. TABLE-US-00020 Component Parts Toluene 19.0 Methyl
ethyl ketone 23.6 VYHH 5.8 Edenol 9790 2.9 DV39600 (product of
Gibraltar 48.6 Chemical identified as iron oxide red pigment
dispersion) DV39420 (product of Gibraltar 0.07 Chemical identified
as carbon black pigment dispersion) DV36500 (product of Gibraltar
0.03 Chemical identified as Pigment Red 178 pigment dispersion)
DV34130 (product of Gibraltar 0.10 Chemical identified as Phtalo
Blue RS pigment dispersion)
[0172] The following coating composition is coated over the dry
paint layer using roll coating at a coat weight of 20-30 gsm and
dried in hot air at a temperature of 105.degree. C. to form a
support or reinforcing layer. In the following table, all numerical
values are in parts by weight: TABLE-US-00021 Component Parts
Toluene 14.1 Methyl ethyl ketone 21.1 VYHH 13.2 Edenol 9790 6.6
DV39600 44.96 DV39420 0.04
[0173] A pigmented pressure sensitive adhesive is then applied over
the coated layer corresponding to support layer 180 at a coat
weight of 17 gsm using transfer lamination to provide an adhesive
layer corresponding to pressure sensitive adhesive layer 120. The
formulation for the pressure sensitive adhesive is as follows: 96%
by weight of a non-tackified acrylic emulsion containing a
cross-linked copolymer of butyl acrylate and 2-ethyl hexyl
acrylate, 3.7% by weight UCD 1106E, and 0.3% by weight UCD
1507E.
EXAMPLE 9
[0174] FIG. 10 illustrates one embodiment of the invention in which
a decorative laminate 89 includes a dry paint layer coated in
sequence onto a release liner 30 which includes a matte release
coat 32 on one side and an adhesive release layer 34 on the side
opposite the dry paint layer. The dry paint layer comprises an
outer clear coat layer 44, one or more decorative print coats 48,
and a color layer 22. A barrier layer 60 is bonded to the color
layer and a tie coat 90 is bonded to the barrier coat and the PSA
layer 28.
[0175] A PET liner is coated on one side with a silicone release
coating corresponding to the adhesive release coat layer. The
thickness of the silicone coated liner is 0.92 mil and comprises
Mitsubishi 92 gauge SLK.
[0176] The matte release coat is applied to the other side of the
release liner using gravure at a coat weight of 4.5 to 5.5 gsm. The
formulation for the matte release coat is as follows (with all
numerical values in parts by weight): TABLE-US-00022 Component
Parts Methyl isobutyl ketone (MiBK) 53.47 Isopropanol 6.49 Lankyd
13-1245 (product of Akzo 7.21 Chemical, identified as an acrylic
modified alkyd) VAGH 8.72 EFKA 5055 (a carboxylic acid ester 1.10
dispersing agent) Microtalc MP 15-38 23.02 Cymel 303 (Cytec
melamine resin) 7.45 Byk 451 (Byk Chemie blocked acid catalyst)
3.50
[0177] In preparing the release coat material the base materials
(VAGH, alkyd and talc) are compounded in a 100 part formula. The
Cymel 303 and Byk 451 are later blended and after the materials are
delivered to the coater the two solutions are blended together. The
matte release coat is dried using forced air at a temperature of
149.degree. C.
[0178] The matte release coat comprises as its crosslinking resin
the melamine (hexamethoxy methyl) resin Cymel 303. The hydroxyl
modified polyvinyl chloride/polyvinyl acetate copolymers (VAGH)
comprise the primary functional resin and the acrylic modified
alkyd comprises a secondary functional resin. The primary
crosslinking resin controls crosslinking and bonds to the polyester
carrier film. The secondary functional resin modifies release of
the dry paint layer (top coat) from the matte release coat. The
blocked acid catalyst accelerates the crosslinking process and the
filler particles, talc, control the degree of microroughness of the
dry matte release coat.
[0179] A transparent clear coat layer is applied to the matte
release coat using gravure at a coat weight of 2.6 to 3.0 gsm and
dried using forced hot air at a temperature of 165.degree. C. The
dry film thickness is 0.09-0.10 mil. The clear coat consists
essentially of a thermoplastic acrylic resinous material,
preferably polymethyl methacrylate. The formulation for the
transparent top coat layer (with all numerical values in parts by
weight) is as follows: TABLE-US-00023 Component Parts MEK 40 MiBK
41 Elvacite 2042 19
[0180] One or more decorative print coats having printing ink
formulations similar to those described in previous examples are
next printed over the transparent top coat layer following
procedures as described previously.
[0181] The following paint coat composition comprises a plasticized
vinyl-based pigmented base coat having an epoxy stabilizer. The tie
coat is coated over the decorative print layers, using roll coating
at a coat weight of 33.0 to 36.0 gsm and dried in hot air at a
temperature of 105.degree. C. to form a color coat layer. The dry
film thickness is 0.65 to 0.73 mil. In the following table all
numerical values are in parts by weight: TABLE-US-00024 Component
Parts NiPar 820 (product of Angus Chemical 15.98 identified as a
blend of 80% nitro propane and 20% nitro ethane) Xylene 23.95
Cyclohexanone 7.71 VYHH 12.76 Edenol 9790 6.38 Stanclere T-883
(product of Adchross 0.06 Chemical identified as a tin heat
stabilizer) EPON 828 (epoxy resin product of Shell) 0.26 DV 39600
(Gibraltar TiO.sub.2 white 32.12 pigment dispersion) DV 396420
(Gibraltar carbon black 0.23 pigment dispersion) DV 36500
(Gibraltar red pigment 0.16 dispersion) DV 34130 (Gibraltar phthalo
blue 0.39 pigment dispersion)
[0182] The following barrier coat layer is coated over the dried
color coat layer at a coat weight of 1.5 to 2.0 gsm. All numerical
values are in parts by weight: TABLE-US-00025 Component Parts
Adcoat 61WG178 (a product of Rohm 45 and Haas identified as acrylic
polymer) Isopropanol 52 Cymel 303 (Cytec melamine resin) 2.4 Cycat
4040 (Cytec paratoluene 0.2 sulfonic acid)
[0183] The barrier layer comprises a cross-linked acrylic resinous
material which is applied by gravure and dried, using forced air at
a temperature of 149.degree. C. The dry film thickness of the
barrier layer is 0.05 to 0.07 mil.
[0184] As mentioned previously, the barrier layer provides a means
for inhibiting or preventing migration of discoloration-causing
pigments into the color-producing layers of the laminate.
[0185] The following tie coat is coated over the dried barrier
layer. All numerical values are in parts by weight: TABLE-US-00026
Component Parts MEK 25.24 MiBK 25.59 VYHH 8.98 Edenol 9790
plasticizer 4.49 Stanclere T-883 0.04 EPON 828 0.18 DV 39600 35.03
DV 39420 0.45
[0186] The tie coat is coated at a coat weight of 2.8 to 3.3 gsm
and with a dry film thickness from about 0.05 to 0.06 mil. The tie
coat enhances adhesion between the barrier layer and the pressure
sensitive adhesive layer. The tie coat is a variation of the color
coat. In the present system, the barrier layer adheres to the color
coat and the PSA adheres well to a similar color coat; so the tie
coat is selected for its ability to provide good adhesion between
the color coat and the PSA. The pigment component of the tie coat
hardens the binder to a useful level.
[0187] The dry film thickness of the decorative laminate of this
Example is within a preferred range of 1.30 to 1.60 mil. In the
described example, the dry film thickness of the combined top coat,
color coat, barrier coat, tie coat and PSA is from 1.35 to 1.51
mil.
[0188] A pigmented pressure sensitive adhesive layer is then
applied to a carrier at a coat weight of 13 to 16 gsm. The dry film
thickness of the PSA is from about 0.45 to 0.55 mil. The PSA is
then applied to the tie coat by transfer lamination. The PSA is
available from Avery Dennison Corporation under product no. S-3526
and the formulation for the PSA is as follows (with numerical
values in parts by weight): TABLE-US-00027 Component Parts S-3506
(product of Avery Dennison, 96.0 Performance Polymers, identified
as a cross-linked copolymer emulsion of butyl acrylate and 2-ethyl
hexyl acrylate) UCD 110GE (white TiO.sub.2 pigment 3.7 dispersion
from Rohm and Haas) UCD 1507E (carbon black pigment 0.3 dispersion
from Rohm and Haas)
EXAMPLE 10
[0189] Gloss measurements taken on the Byk-Mallinckrodt gloss meter
for various paint films as described herein produced the following
gloss readings:
[0190] (1) Release coat--Elvacite 2899/VYNS at a ratio of 14.5:1,
having a standard range of microtalc at 1.0 to 1.1:1 talc to
polymer with Cymel 303
[0191] Top coat--none
[0192] Color coat--Rohm and Haas Acryloid B72/VYHH at a ratio of
1:3 [0193] Gloss at 60.degree.--3.4 [0194] Gloss at
85.degree.--8.8
[0195] (2) Release coat--Elvacite 2899/VYNS at a ratio of 14.5:1,
having a standard range of microtalc at 1.0 to 1.1:1 talc to
polymer with Cymel 303
[0196] Top coat--Rucothane CO A 5002L urethane polymer
[0197] Color coat--Rohm and Haas B72/VYHH at a ratio of 1:3 [0198]
Gloss at 60.degree.--4.9 [0199] Gloss at 85.degree.--8.5
[0200] (3) Film having faux leather finish:
[0201] Release coat--Acrylic modified alkyd with Cymel 303 and
standard range of microtalc at 1.0 to 1.1:1 talc to polymer.
[0202] Top coat--Elvacite 2042 and VYHH/Vitel 220B at 1:1
ratio.
[0203] Gloss at 60.degree.--2.2
[0204] Gloss at 85.degree.--32.4
[0205] (4) Films having release coats and transparent top coat
layers prepared according to Examples 7 and 9 produced gloss
readings within a range from about 26 to about 30 at
85.degree..
EXAMPLE 11
[0206] To measure the "force differential" in terms of carrier
release force versus unwind release force, samples were produced in
two-inch-wide by 12-inch long strips to simulate unwinding of a
roll of the decorative film. A construction under test comprised
the FIG. 3 embodiment having a transparent top coat, pigmented
color layer, a PSA layer with the PSA side of the film exposed, and
a release liner comprising a PET film having a matte release coat
in contact with the top coat and an exposed silicone release coat
on the opposite side of the release liner. In other tests, the
construction was similar to that shown in FIG. 10 in which the same
construction included the barrier layer and the tie coat layer.
[0207] One comparative test used test samples in which the
compositions of the transparent top coat, the color coat and the
PSA layer were generally as described in Examples 7 and 9, which
included the Avery Dennison S-3506 PSA layer (an unpigmented form
of Avery S-3526 adhesive). In other test samples, color coat and
top coat formulations similar to Example 1 were used, in
combination with the Avery S-3506 PSA layer. In further test
samples, a construction involved the top coat and color coat
formulations of Example 1 along with a different Avery Dennison PSA
identified as S-692N adhesive.
[0208] The tests involved peeling the matte release layer away from
the dry paint layer and peeling the silicone side of the release
liner away from the PSA part of the sample. The tests were
conducted at room temperature. In one test, separate adhesive tapes
were attached to the sides of the test samples to test the peel
force at each interface with each tape extending in opposite
directions, each at a 90.degree. angle to the sample. The tests
were performed on a movable sled having adjustable peel rates
which, in one embodiment, were varied in increments from speeds as
low as 12 inches per minute up to 1200 inches per minute. Peel
forces were measured at progressive speed intervals and plotted on
comparative force-versus-peel rate profiles.
[0209] The test results showed that carrier release force is
reasonably uniform across a broad range of release rates, whereas
unwind release forces tend to stay below the carrier release force
at low speeds, but they approach and ultimately exceed the carrier
force at higher speeds. Each profile generated by the tests was
characterized by a cross-over release rate at which the unwind
release force reaches and exceeds the carrier release force.
Generally speaking, the self wound rolls that produced the best
unwind response maintained a carrier release force in excess of the
unwind release force at rates up to about 100 inches per minute.
The test results showed that unwind force for the S-692N PSA
approached carrier release force more rapidly than and exceeded it
at a much lower propagation rate than the S-3506 PSA, which had
superior unwind performance compared to the S-692N PSA. Such
superior unwind performance was characterized by self-wound rolls
of film containing the S-3506 adhesive being unwound without
premature release of the release liner from the dry paint layer;
whereas rolls of film containing the S-692N PSA experienced
unreliable release response.
[0210] It was also observed that the S-3506 PSA exhibited lower
tack levels and had less cold flow than the S-692N PSA. This was
attributed to the S-3506 PSA having an internally cross-linked
structure which produced the lower tack levels and lower cold flow
than the S-692N PSA which was not internally cross-linked and had
higher tack levels, as well as higher cold flow. This difference in
PSA properties caused the non-cross-linked PSA to stick more to the
silicone side of the release liner and raised the unwind release
force to levels that were too high and produced unreliable unwind
response compared to the cross-linked PSA which produced more
desirable (lower) unwind release force levels.
EXAMPLE 12
[0211] Test panels containing barrier coats were prepared and
tested for color shift. The test panels included a blue color layer
similar to the color layer of Example 9 and a cross linked acrylic
PSA layer, Avery's S-3506, similar to the PSA used in Example 9.
The test films were applied to a yellow (Hansa Yellow 10G) painted
surface and subjected to accelerated aging. The test films were
measured for discoloration (color shift) caused by migration of
azo-type color constituents that passed from the painted surface
through the PSA layer to the color layer of the test sample. The
test panels were prepared by using a dry paint color layer
containing a plasticized vinyl-based paint layer containing a
dispersed blue pigment. The S-3506 PSA was applied to the color
layer. A medium yellow painted substrate was prepared using Behr
1300 deep base (5 ounces medium yellow per gallon base) applied at
7.5 mils wet coating to 3 mil polyester. The paint coat was allowed
to dry for three hours minimum at room temperature then force air
dried for five minutes at 250.degree. F. The C.I.E. test procedures
were used to measure .DELTA. b* color change on the test panel at
60.degree. C.
[0212] The following table shows six separate barrier coatings
which were evaluated for color shift using these test procedures.
Test sample 1 was a cross-linked low molecular weight acrylic
barrier coat; test samples 2 and 3 were thermoplastic low molecular
weight acrylic barrier coats containing filler or additive
materials for reducing color transmission; test samples 4 and 5
were thermoplastic low-molecular weight acrylic barrier layers that
included the filler or additive materials, but also included PVP as
an adhesion promoter; and test sample 6 was a high molecular weight
thermoplastic acrylic barrier coat in the absence of any additive,
filler or adhesion promoter. The materials contained in each test
sample are shown in parts by weight. TABLE-US-00028 Barrier Coat
Test Samples Materials #1 #2 #3 #4 #5 #6 Adcoat 61WG178 45.0 54.2
61.5 46.5 44.7 acrylic Degussa Alum. Ox. 2.5 0.9 2.1 0.7 Halox
Xtain A 2.5 0.9 2.1 0.7 IPOH 52.4 40.8 36.7 35.0 26.6 20.0 Cymel
303 2.4 Cycat 4040 0.2 PVP K80 14.3 27.3 Toluene 70.7 Elvacite 2041
9.3 acrylic
[0213] The following test results for test samples #1 through #6
show color shift data for PSAs applied by both direct coating and
by transfer-lamination. TABLE-US-00029 Test Samples Materials #1 #2
#3 #4 #5 #6 Coat weight (gsm) 1.6 4.9 4.7 2.6 2.4 0.8 Direct
adhesion good good good good good good Color change 60.degree. C.
0.38/ 0.37/ 0.35/ 0.4/ (.DELTA.b*) 1170 hrs 552 hrs 1002 hrs 1002
hrs Transfer- poor poor poor good good good lamination adhesion
Color change 60.degree. C. 0.47/ 0.97/ 0.61/ 0.89/ 0.39/ 0.38/
(.DELTA. b*) 162 hrs 239 hrs 330 hrs 201 hrs 376 hrs 552 hrs
[0214] A similar test was conducted using the cross-linked acrylic
barrier coat of test sample #1 with the following tie coat (in
parts by weight): TABLE-US-00030 Tie Coat Material Parts MEK 25.22
MiBK 25.59 Dow VYHH 8.98 Plastolein 9790 4.49 Stanclere T-883 0.04
Dow EPON 828 0.18 DV39600 (Gibraltar White) 35.30 DV29420
(Gibraltar Black 0.45 Disp.) MiBK 4.00
[0215] The product having the tie coat was tested as 60.degree. C.
for 401 hours. Samples for color shift measurement were taken
throughout the roll. An average of 0.24 .DELTA.b* color change
resulted with a standard deviation of 0.06. The tie coating was
used in this test because the adhesive was applied by
transfer-lamination, and the tie coat was needed to increased
adhesion between the barrier coat and the pressure sensitive
adhesive.
[0216] Similar barrier polymer tests were conducted in which the
C.I.E. .DELTA.b* color shift was measured for different test
samples, and then the color change that would occur at 60.degree.
C. for 16 days was estimated. TABLE-US-00031 Coat wt. Final Proj.
Barrier Polymer (gsm) Hrs. 16 days (1) Thermoplastic acrylic - R
& H 2.5 400 1.82 61WG178 (2) Same as (1) 2.5 308 4.86 (3)
Cross-linked acrylic - R & H 1.8 1337 0.25 61WG178/15 phr Cymel
303/1 phr Cycat 4040 (4) Same as (3) 1.6 497 0.37 (5) Same as (3)
1.6 227 0.96 (6) Cross-linked acrylic - R & H 1.8 1337 0.30
61WG178/10 phr Cymel 303/1 phr Cycat 4040 (7) Cross-linked acrylic
- R & H 1.6 487 0.22 61WG178/15 phr Cymel 303/1 phr Cycat
4040/5 phr Ti02/9 phr AlO.sub.x (8) Thermoplastic acrylic - R &
H 2.0 427 0.12 61 WG 178/15 phr AlO.sub.x/15 phr Xtain.
[0217] General observations from these tests are that cross-linking
of the low molecular weight acrylic barrier layer produces good
color shift improvements into the acceptable range. Addition of
titanium dioxide, aluminum oxide and similar metal compounds and
oxides and salts further improve the barrier properties of both
thermoplastic and cross-linked polymeric barrier layers.
[0218] The present invention has been described with respect to
multilayer laminates used as a wall film for interior architectural
applications, but the laminate also is useful in other applications
as well. These would include exterior architectural applications
such as siding panels and wall surfaces; outdoor decorative items
and signs; interior automotive decorative and functional uses such
as dashboards and panels; and exterior automotive uses including
automotive body parts, trim parts and panels.
* * * * *