CROSS REFERENCES TO RELATED APPLICATIONS
Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
Not Applicable.
TECHNICAL FIELD
This invention relates to time indicator assemblies, and in particular
to a time indicator assembly including migrating ink that migrates through an opaque
layer of material forming part of the assembly to produce a viewable image after
a period of time.
DESCRIPTION OF THE BACKGROUND ART
A known time indicator assembly 1 including migrating ink 2, such
as shown in Fig. 1, produces a visible image after a period of time. The migrating
ink 2 is applied to a base material 3, such as by printing, to form a back part
4 of the assembly 1. The back part 4 is adhesively joined with a front part 5 formed
from one or more layers 7, 8, 9 of opaque and/or transparent material or coatings
by an adhesive 6 to form and activate the assembly 1. Over a period of time, the
migrating ink 2 of the activated assembly 1 migrates through the adhesive 6 to form
a viewable image. The front part 5 and the back part 4 are not joined together until
activation of the time indicator assembly 1 is desired. As a result, properly aligning
the front part 5 and back part 4 to form and activate the assembly can be difficult.
This problem is solved by a time indicator assembly having a front
part and a back part adhesively joined at one edge, such as disclosed in U.S. Pat.
Nos. 5,107,470 and 5,974,003 which are fully incorporated herein by reference. These
patents disclose an assembly having a front part and a back part similar to the
time indicator assembly shown in Fig. 1. The back part includes migrating ink applied
to a base material, and the front part includes one or more opaque coatings or layers.
In order to ensure the front part and the back part are properly aligned, an edge
of the front part is adhesively joined to the back part adjacent to the migrating
ink. Prior to activation, a release liner interposed between the migrating ink and
the front part prevents the migrating ink from contacting the front part and migrating
through the opaque layers. When a user wishes to activate the assembly and initiate
migration of the ink, the release liner is removed and the portion of the front
part overlying the migrating ink is joined to the back part.
Since only one edge of the front part is joined to the back part,
the front part is free to flop around. The floppy front part causes havoc when printing
on outer surfaces of the assembly. Moreover, in one embodiment disclosed in the
'470 patent, the release liner is folded over to form a pull tab for removing the
release liner and activating the assembly. Prior to activation of the assembly,
this folded release liner forms an assembly having an uneven thickness which causes
further problems when attempting to print on an outer surface of the assembly.
SUMMARY OF THE INVENTION
The present invention provides a time indicator assembly having a
front part and a back part that can easily pass through a printer. The assembly
includes a base substrate forming at least part of the back part having a first
surface and a second surface extending between edges. A migrating ink is applied
over a portion of the first surface of the base substrate, and a release sheet overlies
the migrating ink to prevent migration of the migrating ink toward the front part.
In one embodiment, an adhesive is applied over the release sheet and onto the base
substrate. The adhesive joins a cover substrate forming at least part of the front
part to the base substrate over at least a portion of the release sheet along at
least two of the front part edges to prevent the cover substrate from flopping around.
Upon removal of the release sheet, the migrating ink migrates through the adhesive
to form the image in the cover substrate. In another embodiment a lift strip is
formed in at least one of the front part and the back part for easily separating
the front part and the back part to expose and remove the release sheet.
A general objective of the present invention is to provide a time
indicator assembly having a non-floppy front part. This objective is accomplished
by securing the front part to at least two edges of the back part.
Another objective of the present invention is to provide a time indicator
assembly having a front part that is easily separated from the back part to expose
a release liner for easy removal. This objective is accomplished in one embodiment
of the present invention by providing a lift strip in the one of the front part
and back part.
The foregoing and other objectives and advantages of the invention
will appear from the following description. In the description, reference is made
to the accompanying drawings which form a part hereof, and in which there is shown
by way of illustration a preferred embodiment of the invention. Such embodiment
does not necessarily represent the full scope of the invention, however, and reference
is made therefore to the claims herein for interpreting the scope of the invention.
BRIEF SUMMARY OF THE DRAWINGS
Fig. 1 is a cross sectional view of a prior art time indicator assembly
formed from two independent parts;
Fig. 2 is a perspective view of a time indicator assembly incorporating
the present invention in the form of a badge prior to activation;
Fig. 3 is a perspective view of the time indicator assembly of Fig.
2 after activation;
Fig. 4 is a sectional view along line 4-4 of Fig. 2;
Fig. 5 is a sectional view of another embodiment of a time indicator
assembly incorporating the present invention; and
Fig. 6 is a sectional view of yet another embodiment of a time indicator
assembly incorporating the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A time indicator assembly 10 in the form of a badge is shown in Figs.
2-4, and includes a front part 12 having at least two edges 14, 16 fixed relative
to a back part 18 by a pressure sensitive adhesive 20. Migrating ink 22 applied
to a top surface 24 of the back part 18 is separated from the adhesive 20 by a release
sheet 26. The time indicator assembly 10 is activated by removing the release sheet
26 and pressing the front part 12 and back part 18 together. Upon activation, the
migrating ink 22 migrates through the adhesive 20 until it is visible through a
transparent outer layer 28 forming part of the front part 12. Advantageously, fixing
at least two edges of the front part 12 relative to the back part 18 prevents the
front part 12 from flopping prior to use and when the time indicator assembly 10
passes through a printer that prints indicia on an exposed surface 66 of the time
indicator assembly 10.
The back part 18 includes a base substrate 30 upon which the migrating
ink 22 is printed. The base substrate 30 has a periphery defined by the edges 32,
34, 36, 38, and includes the top surface 24 of the back part 18 and a bottom surface
31. In the embodiment disclosed herein, the base substrate 30 is rectangular having
four edges 32, 34, 36, 38, however, the base substrate 30 can have any shape, such
as a circle wherein each edge is defined by an arc of approximately 90 degrees.
The base substrate 30 can be formed from one or more layers of material, such as
paper, cardboard, plastic, foil, and the like, without departing from the scope
of the invention. Moreover, the back part 18 can include a pressure sensitive adhesive
40 applied to the bottom surface 31 of the base substrate 30 and covered with a
release liner 42 to form a badge useable as a name tag that can releasebly adhere
to a user's clothing.
In the embodiment disclosed in Figs. 2-4, the migrating ink 22 is
applied to a portion of the back part top surface 24 and spaced inwardly from at
least two of the base substrate edges 32, 34, 36, 38. The migrating ink 22 defines
an image 44, or other indicia, such as alphanumeric characters, symbols, graphic
designs, stripes, and the like. The migrating ink 22 can be any known ink which
upon contact with the adhesive 20 migrates therethrough to form the image 44 in
the front part 12, such as disclosed in U.S. Pat. No. 4,212,153 which is fully incorporated
herein by reference. Forming an image 44 in the front part 12 or cover substrate
60 does not require the migrating ink 22 to migrate into any part of the front part
12 or cover substrate 60. The image 44 must, however, be at least viewable through
the front part 12 or cover substrate 60 to be formed in the front part 12 or cover
substrate 60. Of course, non-migrating ink can be applied to the base substrate
30 to hide the image 44 formed by the migrating ink 22, and/or reduce the contrast
between the background color seen through the front part 12 and the image 44, without
departing from the scope of the invention.
The release sheet 26 overlies the migrating ink 22 and separates the
migrating ink 22 from the adhesive 20 to prevent activation of the time indicator
assembly 10. The release sheet 26 can be formed from any known material impervious
to the migrating ink 22 and releasable from the adhesive 20, such as coated paper,
foil, and the like, without departing from the scope of the claims.
The adhesive 20 overlies the release sheet 26 and base substrate 30
to form an adhesive layer that fixes the front part 12 relative to the base substrate
30. The adhesive 20 can be any adhesive known in the art, such as a rubber or acrylic
based pressure sensitive adhesive. In one embodiment, the adhesive 20 includes an
opaqueing agent, such as titanium dioxide blended in a polymer mixture, to form
an opaque adhesive which obscures the migrating ink 22 from view as the migrating
ink 22 migrates therethrough. Of course, the adhesive 20 can be clear and an opaque
layer forming part of the front part 12 can be provided to obscure the migrating
ink 22 from view as the migrating ink 22 migrates through the adhesive 20 and opaque
layer following activation of the time indicator assembly 10.
The adhesive 20 is applied over the release sheet 26 and onto the
base substrate 30 adjacent at least two of the front part edges 14, 16 to fix the
two edges 14, 16 of the front part 12 relative to the two edges 32, 34 of the base
substrate 30. The edges 14, 16 of the front part 12 fixed relative to the base substrate
30 can be opposing edges, such as edges 14, 16, or adjacent edges, such as edges
14, 50, without departing from the scope of the invention. Advantageously, by fixing
at least two edges of the front part 12 relative to the base substrate 30, the front
part 12 is prevented from flopping around which allows the time indicator assembly
10 to pass through a printer without jamming the printer. Advantageously, the adhesive
20 can be spaced inwardly from at least one edge of the front part 12 to allow a
user to slip a fingernail, or other object, between the front part 12 and base substrate
30 to separate the front part 12 from the base substrate 30 to expose and remove
the release sheet 26.
In the embodiment disclosed herein, the front part 12 is bounded by
the edges 14, 16 and edges 50, 52 which coincide with edges of a cover substrate
60 forming the front part 12. The cover substrate 60 is formed from an inner layer
62 and the outer layer 28 of material which overlies and covers the migrating ink
22. The cover substrate 60 is joined to the base substrate 30 and the release sheet
26 by the adhesive 20. Although only two layers 62, 28 are disclosed, any number
of layers can be used to form the cover substrate 60 without departing from the
scope of the invention.
The inner layer 62 can be formed from an opaque material including
a non-porous polymer containing titanium oxide, or other opaqeuing agent, through
which the migrating ink 22 can migrate. Of course, if the adhesive 20 is opaque,
the opaque inner layer 62 can be eliminated, or be substituted with a transparent
layer, such as a non-porous polymer including plasticized PVC (polyvinyl chloride),
semiplasticized PVC, acrylics, polyurethanes and hytrel, and the like, without departing
from the scope of the invention. Moreover, any number of inner layers can be provided
without departing from the scope of the invention.
The outer layer 28 is transparent and impervious to the migrating
ink 22, such as a clear inert acetate or polyester film, to allow a user to see
the image 44 formed by the migrating ink 22 once it has migrated through the adhesive
20 and/or opaque inner layer 62 while preventing external migrating ink from passing
through the outer layer 28 from an external source of migrating ink. Preferably,
ink can be applied to an outwardly facing surface 66 of the outer layer 28, such
as by printing, stenciling, writing, and the like, to form indicia 68 on the outwardly
facing surface 66.
A lift strip 64 is formed in the back part 18 adjacent to the migrating
ink 22 by forming a cut 33 spaced inwardly from one edge 34 of the back part 18.
The lift strip 64 is adhesively fixed to the front part 12, and permits a person
to easily lift the front part 12 to expose and remove the release sheet 26 to activate
the assembly 10. Although forming the lift strip 64 in the back part 18 is disclosed,
the lift strip 64 can be formed in the front part 12 without departing from the
scope of the invention.
In use, the time indicator assembly 10 including the release sheet
26 interposed between the front part 12 and back part 18 is passed through a printer
for printing indicia 68 thereon. Advantageously, by securing the front part 12 and
back part 18 relative to each other by fixing at least two edges 32, 34 of the base
substrate 30 relative to two edges 14, 16 of the front part 12, the front part 12
cannot flop around and jam the printer. In Fig. 2, the front part edge 52 is shown
rolled back from the base substrate edge 38 to show the release sheet 26 disposed
therebetween.
The time indicator assembly 10 is activated by a user grasping the
lift strip 64 and separating the front part 12 from the back part 18 without breaking
the adhesive bond between at least one pair of adhesively bonded edges, such as
edges 32, 14, to expose the release sheet 26. The release sheet 26 is removed and
the front part 12 and the back part 18 are then pressed together to urge the adhesive
20 into contact with the migrating ink 22 to activate the time indicator assembly
10. Advantageously, by maintaining one pair of edges, such as edges 32, 14, together,
the edges of the front part 12 and back part 18 remain aligned when pressed together.
In other embodiments shown in Figs 5 and 6 where like components are
assigned like reference numbers, an adhesive 70 can be interspersed with the migrating
ink 22, such as shown in Fig. 5, or applied adjacent to the migrating ink 22, such
as shown in Fig. 6, to fix the release sheet 26 relative to the back part 18 which
is adhesively fixed to the front part 12 to fix at least two edges of the front
part 12 relative to the back part 18. Advantageously, in the embodiment shown in
Fig. 6, the lift strip 64 is adhesively fixed to the release sheet 26 which is easy
to grasp for removing the release sheet 26. Advantageously, in all of the embodiments,
the release sheet 26 remains flat to provide a flat surface for printing on the
time indicator assembly 10, and the time indicator assembly 10 remains inert in
its composite construction prior to removal of the release sheet 26. Of course,
the release sheet 26 can be folded or extend past one of the edges of the time indicator
assembly 10 to provide a tab for easy removal of the release sheet 26.
While there has been shown and described what is at present considered
the preferred embodiment of the invention, it will be obvious to those skilled in
the art that various changes and modifications can be made therein without departing
from the scope of the invention defined by the appended claims.
In summary a time indicator assembly including a front part and
a back part is disclosed that can easily pass through a printer. The time indicator
assembly includes a base substrate forming at least part of the back part having
a first surface and a second surface extending between edges. A migrating ink is
applied over a portion of the first surface of the base substrate, and a release
sheet overlies the migrating ink to prevent migration of the migrating ink toward
the front part. In one embodiment, an adhesive is applied over the release sheet
and onto the base substrate adjacent at least two of the base substrate edges. The
adhesive joins a cover substrate forming at least part of the front part to the
base substrate over at least a portion of the release sheet and along the at least
two of the base substrate edges. Upon removal of the release sheet, the migrating
ink migrates through the adhesive to form an image in the cover substrate. In another
embodiment a lift strip is formed in at least one of the front part and back part
for easily separating the front part and back part to expose and remove the release
sheet.