WO2003069586A2

WO2003069586A2 - Adhesive coated thin film label

Info

Publication number: WO2003069586A2
Application number: PCT/US2003/002492
Authority: WO
Inventors: Richard Fearn; Richard Spear
Original assignee: Spear U.S.A., L.L.C
Priority date: 2002-02-12
Filing date: 2003-01-29
Publication date: 2003-08-21
Also published as: EA005717B1; WO2003069586A3; US20030152722A1; AU2003214922A1; DE60301334T2; DE60301334D1; US6818271B2; EP1476861A2; DK1476861T3; ZA200406024B; MXPA04007782A; CN1630891A; CA2475223A1; JP2005517981A; CA2475223C; ATE302458T1; EP1476861B1; CN1630891B; EA200401030A1; ES2250877T3

Abstract

An adhesive coated thin film label (10) and a method for applying a thin film label to a substrate (32). The thin film label (10) has a thickness less than 1.0 mil and is die cut to define a label shape. The label (10) includes visible indica (14, 16) and adhesive (22) is applied to one side of the label film (12) for bonding to the substrate (32). The label (10) may further be provided in roll form (30) mounted on a release liner (24).

Description

ADHESIVE COATED THIN FILM LABEL

Pursuant to 37 C.F.R. § 1 .78(a)(4), this application

claims the benefit of and priority to prior filed co-pending Provisional

Application Serial No. 60/356,283, filed February 12, 2002, which is

expressly incorporated herein by reference.

Field of the Invention

This invention relates to labels for containers, and more

particularly to adhesive coated thin film labels.

Background of the Invention

Printed labels are widely used on containers to identify the

particular products, manufacturers and brand names associated with the

products in those containers. Conventional paper labels have been widely

used for many years, however paper labels suffer several drawbacks, such

as susceptibility to abrasion and poor adhesion in wet or moist conditions. An increasingly popular means of labeling containers has been through the

use of pre-printed thin film labels. Thin film labels are made from a web of

polymeric material printed with desired indicia and applied to containers

with an adhesive. These thin film labels provide a printed-on look to the

containers to which they are applied and result in a label which is generally

more durable than conventional paper labels. Thin film labels are generally

die cut from the web of polymeric material to define a discrete label shape

and are often provided on a web of carrier material such as a release liner.

It is desirable to make thin film labels from as thin a film as

possible. Thinner films increase the aesthetic appearance of the labels,

reduce overall material costs, and improve efficiency in the label application

process. For example, as the thickness of the film is decreased, more labels

may be supplied on a length of release liner which is to be wound into a

given size roll. Conventional thin film labels generally have been made with

thicknesses in the range of 2 to 3 mils, or even greater. It has long been

desired to decrease the thickness of thin film labels to less than about 1

mil. However prior attempts to produce and apply labels less than about 1

mil in thickness in production environments have heretofore been

unsuccessful.

While thin labels are desirable, they also create problems,

particularly in the manufacture of the labels and the application of the labels

to their respective containers. Very thin film labels exhibit relatively low

stiffness, whereby attempts to dispense very thin film labels having a

thickness of about 1 mil or less, from conventional peel tip equipment have been unsuccessful. Thinner labels also introduce durability issues into

automated label application processes. Because the automated processing

equipment used to package containers to which the labels will be applied

are often run at high speeds, the labels must be applied to the containers at

speeds which are sufficiently similar to the speed of the processing

equipment. Such high speed application requirements often cause very thin

film labels to stretch or split during the application process. The use of very

thin films for labels stock also makes it difficult to die cut individual labels

from the web of film stock without cutting through the carrier web of

release liner.

There is thus a need for a very thin film label which may be

applied to containers in high speed production lines, and which overcomes

problems of prior art thin film labels, such as those described above.

Summary of the Invention

The present invention provides a thin film label having a

thickness in the range of 0.1 mil to 1 .0 mil, which may be applied to

substrates, such as glass or plastic bottles, or other containers. The label

may be dispensed from conventional peel tip equipment to a desired

container at production line speeds without damaging the label. The label

may be die cut from a web of polymeric material with an adhesive on one

side of the label film for bonding to the substrate.

In one aspect of the invention, multiple labels may be supplied

on a web of release material for convenient dispensing in a packaging

production line. It has been discovered that use of a low release value on very thin film labels will cause the labels to dispense from a peel tip when

the labels have been "stiffened" by applying ink in the form of graphics on

the labels. The release value of the adhesive acts in conjunction with the

tension and speed of the web of liner material to dispense the thin film

labels to a substrate as the liner web passes over a peel tip.

In another aspect of the invention, an exemplary thin film label

may be made by forming a laminate from an elongate web of thin film, a

web of release liner, and adhesive disposed between the film and release

liner. Visible indicia are applied to the film and the film is die cut to define

discrete label shapes and a matrix of waste film. The matrix is stripped

from the laminate, leaving the discrete thin film labels on the web of release

liner.

The features and objectives of the present invention will

become more readily apparent from the following Detailed Description taken

in conjunction with the accompanying drawings.

Brief Description of the Drawings

The accompanying drawings, which are incorporated in and

constitute a part of this specification, illustrate embodiments of the

invention and, together with a general description of the invention given

above, and the detailed description given below, serve to explain the

invention.

FIG. 1 is a plan view of an exemplary thin film label of the

present invention; FIG. 2 is a partial cross-sectional view of the thin film label of

FIG. 1 , taken along line 2-2;

FIG. 3 is a perspective view of a series of thin film labels on a

release liner and provided in a roll; and

FIG. 4 is a schematic illustration depicting the dispensing and

application of thin film labels to containers.

Detailed Description

Referring to FIGS. 1 and 2, there is shown an exemplary

adhesive coated thin film label 10 according to the present invention. The

label 10 includes a very thin label film having a thickness of approximately

0.1 mil to approximately 1 .0 mil. The label is die cut to a desired shape

and further includes visible indicia 14,16 selectively applied to the label film

12 to create letters, numbers, decorative designs, or any combination

thereof. The visible indicia 14, 16 may be created, for example, by

applying ink, hot stamped foil, or embossed images to the label film 1 2.

In the exemplary label shown in FIG. 1 , the label includes an

opaque printed area 18 defining a background and decorative designs 16

and indicia 14 printed on top of the background. The background 18 does

not cover the entire label surface and therefore the label 10 has a border 20

which comprises only the label film 1 2. In an exemplary embodiment, the

label film 12 is clear, however the label film 12 may be manufactured to

have any color desired. For example, the label film 12 may be

manufactured to have an opaque, white color which gives the look of a

paper label, while retaining the advantages of thin film labels. The label 10 further includes an adhesive 22 applied to one

side of the label film 12, for securing the label 10 on a substrate, such as a

container. The adhesive 22 may be pressure sensitive adhesive, heat

activated adhesive, water activated adhesive, or any other type of adhesive

suitable for securing the label on a substrate. In an exemplary embodiment,

the adhesive 22 is a pressure sensitive acrylic adhesive. In another

exemplary embodiment, the adhesive 22 has a release value not greater

than 15g, as measured in a TMI release tester according to a modified

FINAT test method, wherein a two-inch wide sample is pulled through an

angle of 180 degrees at 1200 inches per minute. This release value is

lower than release values typically used for such labels. The visible indicia

14, 16 may be applied to either side of the label film 12 to produce a

desired effect. For example, the visible indicia 14, 1 6 may be applied as a

reverse image on the same side of the label film 12 that the adhesive 22 is

applied, whereby the image may be viewed through the label film 12 after

the label 10 has been applied to a container.

In an exemplary embodiment, the thin film label 10 further

includes a release liner 24 applied to the adhesive side of the label film 12.

The release liner 24 protects the adhesive 22 and prevents premature

bonding of the adhesive 22 prior to application on a desired container.

The release liner 24 may be of any suitable material, such as polyester film,

and generally has a thickness of about 1 .0 mil. In an exemplary

embodiment, the release liner 24 is a polyester film having a thickness of

0.7 mil. The release liner 24 may be provided in an elongated web which supports several individual thin film labels 10. The elongated web of

release liner 24 may generally be wound into a roll 30 for convenient

storage and dispensing of the thin film labels 10, as depicted in FIG. 3.

Advantageously, the thin film labels 10 of the present

invention have a thickness which is much less than conventional thin film

labels currently in use. Conventional thin film labels generally have

thicknesses greater than 1 .0 mil, and typically on the order of 2.0 mils or

more. The thinner labels of the present invention provide benefits in the

form of improved aesthetic appearance of containers to which the labels are

applied and increased durability of the labels. Furthermore, because the

label film 1 2 is thinner than previous thin film labels, more labels 10 may be

provided on a given size roll 30 of labels. Accordingly, the rolls 30 will

require less frequent replacement when used in conventional label

application equipment, thereby improving production efficiency.

The label film 12 comprises a web of polymeric material such

as polypropylene, polyethylene, PVC, or other suitable polymeric material.

In an exemplary embodiment, the label film 12 is made from biaxially

oriented polypropylene.

An exemplary thin film label 10 of the present invention may

be made by applying an adhesive 22 to an elongate web of liner material

24, applying label film 12 having a thickness between approximately 0.1

mil and approximately 1.0 mil to the liner 24 and adhesive 22 to form a

laminate, selectively applying indicia 14, 16 on the label film 1 2, die cutting

the label film 1 2 to define discrete labels 10 and a matrix of waste material, and stripping the matrix of waste material from the laminate so that only

the discrete labels 10 remain on the liner material 24.

Referring to FIG. 4, an exemplary method of applying a thin

film label 10 to a substrate, such as a container 32 will now be described.

At least one thin film label 10 having a thickness less than approximately

1 .0 mil is provided on a web of liner material 24 wound in a roll 30. The

web of liner material 24 is moved over a peel tip 34 to bend the liner

material 24, whereby the label 10 is caused to separate from the liner

material 24 without tearing the label 10. In an exemplary embodiment, roll

30 is driven by a first motor (not shown) and take-up reel 36 is driven by a

second motor (not shown) to move the web of liner material 24 past the

peel tip 34 while controlling the tension and speed of the web such that the

release value of the adhesive 22 is exceeded when the label 10 passes over

the peel tip 34. In addition, rollers may be used on both sides of the peel

tip 34 to control the path and/or tension and speed of the web of liner

material 24.

A container 32 is placed near the peel tip 34 to receive the

label 10 as it is dispensed from the web of liner material 24. The speed of

the container 32 relative to the speed of the moving web is controlled such

that the container 32 moves slightly faster than the dispensed label 10. A

wiper 35 is positioned adjacent peel tip 34 to wipe label 10 as it is applied

to container 32 to ensure that no air is trapped between the label 10 and

the container 32. The used release liner 24 is wound onto take-up reel 36. Specific examples of very thin film adhesive labels according to

the present invention, and application of the labels to glass bottles, will now

be discussed.

EXAMPLE 1 :

1 mil thick labels were applied to glass bottles on a Spear

Model 5000 labeling machine at a rate of about 265 bottles/min. Two label

constructions made by FLEXcon Corp., Spencer, Massachusetts, were

tested:

Group A: 1 .0 mil thick polypropylene film with type A-45 emulsion

acrylic adhesive and 1 .5 mil thick polyethylene terephthalate (PET) release

liner; and

Group B: 1 .0 mil thick polypropylene film with type A-45 emulsion

acrylic adhesive and 2.0 mil thick PET release liner.

1 800 samples of each label construction were applied to glass

bottles by the labeling machine. All but six labels from Group A and eleven

labels from Group B satisfactorily dispensed to the bottles.

EXAMPLE 2:

1 mil thick labels were applied to glass bottles on a Krones

Autocol labeling machine at a rate of about 265 bottles/min. Two label

constructions made by FLEXcon Corp., Spencer, Massachusetts, were

tested:

Group A: 1 .0 mil thick polypropylene film (Mobil 434) with type A-34

solvent acrylic adhesive and 1 .0 mil thick PET release liner; and Group B: 1 .0 mil thick polypropylene film (Mobil 434) with type A-32

solvent acrylic adhesive and 1.0 mil thick PET release liner.

A wiping mechanism was used to wipe the labels after being

dispensed to the bottles. The wiping mechanism included a 1 .5-inch

diameter soft foam roller, a 9-inch Teflon-coated soft foam pad, and a brush

having long plastic bristles. The peel tip was modified by sharpening the tip

to have an end radius of approximately 1 /64-inch and the position of the tip

was adjusted to form an acute web angle around the tip. 1000 labels from

each group were applied to the glass bottles. All labels dispensed

satisfactorily. Minor label wrinkles were observed in 25% to 30% of the

bottles labeled with Group A labels. Approximately 5% of the bottles

labeled with Group B labels were observed to have minor label wrinkles.

EXAMPLE 3:

0.7 mil thick labels were applied to glass bottles on a Kosme

960 labeling machine. The labels comprised 0.7 mil thick polypropylene

film (Mobil 434) with type A-32 solvent acrylic adhesive and 1 .0 mil thick

PET release liner made by FLEXcon Corp., Spencer, Massachusetts. All

labels were observed to apply satisfactorily to the bottles and it was

determined that only minor changes in the wiper were needed for running at

production speeds.

As shown in the examples above, the very thin film labels of

the present invention, with thicknesses of 1 mil and less, have been

demonstrated to be capable of being dispensed to containers by automated equipment and at line speeds compatible for use in conjunction with

automated packaging and bottling equipment. The present invention thus

overcomes drawbacks of prior art thin film labels which, heretofore, could

not be satisfactorily dispensed to containers, such as bottles, when the

thickness of the labels was reduced to 1 mil or less. Furthermore, the

labels of the present invention were successfully dispensed to bottles

without tearing or otherwise distorting appearance of the labels.

While the results described above represent a significant

improvement over prior art labels, it will be recognized by those skilled in

the art that further improvements in terms of increased application rates,

reduced wrinkling, and reduced numbers of non-dispensed labels are

possible by making further adjustments to the automated labeling

equipment. These types of adjustments are commonly made by operators

while the equipment is running, to account for variations in characteristics

of different labels and variations in equipment parameters that occur over

time.

While the present invention has been illustrated by the

description of the various embodiments thereof, and while the embodiments

have been described in considerable detail, it is not intended to restrict or in

any way limit the scope of the appended claims to such detail. Additional

advantages and modifications will readily appear to those skilled in the art.

The invention in its broader aspects is therefore not limited to the specific

details, representative apparatus and methods and illustrative examples

shown and described. Accordingly, departures may be made from such details without departing from the scope or spirit of applicant's general

inventive concept.

WHAT IS CLAIMED IS:

Claims

1 . An adhesive coated thin film label, comprising:

label film having a thickness of approximately 0.1 mil to

approximately 1 .0 mil, the label film being die cut to define a label shape

and having a first surface and a second surface opposite said first surface;

an adhesive disposed on one of said first and second surfaces

of said label film; and

visible indicia selectively disposed on at least one of said first

and second surfaces to define a viewable label image.

2. The adhesive coated thin film label of claim 1 wherein said

adhesive is a pressure sensitive acrylic adhesive.

3. The adhesive coated thin film label of claim 1 wherein said

adhesive has a release value not greater than approximately 15 grams.

4. The adhesive coated thin film label of claim 1 :

wherein said label film has a thickness of at least

approximately 0.3 mil; and

wherein said label film has a thickness not greater than

approximately 0.9 mil.

5. The adhesive coated thin film label of claim 1 :

wherein said label film has a thickness of at least

approximately 0.5 mil; and

wherein said label film has a thickness not greater than

approximately 0.8 mil.

6. The adhesive coated thin film label of claim 1 wherein said

label film has a thickness of approximately 0.7 mil.

7. The adhesive coated thin film label of claim 1 wherein said

label film comprises biaxially oriented polypropylene.

8. The adhesive coated thin film label of claim 1 further

comprising a releasable liner disposed on said adhesive.

9. The adhesive coated thin film label of claim 8:

wherein said liner has a thickness of at least approximately 0.1

mil; and

wherein said liner has a thickness not greater than

approximately 1 .0 mil.

1 0. The adhesive coated thin film label of claim 8:

wherein said liner has a thickness of at least approximately 0.3

mil; and

wherein said liner has a thickness not greater than

approximately 0.9 mil.

1 1 . The adhesive coated thin film label of claim 8 wherein said

liner has a thickness of approximately 0.7 mil.

1 2. A supply of thin film labels, comprising:

an elongate web of liner material for supporting labels;

a plurality of discrete die cut labels releasably disposed on said

liner material and having a thickness between approximately 0.1 mil and

approximately 1 .0 mil, each label having a first surface and a second

surface opposite said first surface;

an adhesive disposed on one of said first and second surfaces

of said plurality of labels, between said labels and said liner material; and

visible indicia selectively disposed on at least one of said first

and second surfaces to define a viewable label image.

1 3. The supply of thin film labels of claim 1 2:

wherein said labels have a thickness of at least approximately

0.1 mil; and

wherein said labels have a thickness not greater than

approximately 0.9 mil.

1 4. The supply of thin film labels of claim 1 2:

wherein said labels have a thickness of at least approximately

0.3 mil; and

wherein said labels have a thickness not greater than

approximately 0.8 mil.

15. The supply of thin film labels of claim 12 wherein said labels

have a thickness of approximately 0.7 mil.

1 6. A labeled product package, comprising:

a container having a surface for receiving a label; and

a label disposed on said surface, said label comprising:

label film having a thickness of approximately 0.1 mil to

approximately 1 .0 mil, wherein said label film is die cut to define a label

shape and has a first surface and a second surface opposite said first

surface,

an adhesive disposed on one of said first and second surfaces

of said label film, and

visible indicia selectively disposed on at least one of said first

and second surfaces to define a viewable label image.

1 7. The labeled product package of claim 1 6:

wherein said label film has a thickness of at least

approximately 0.3 mil; and

wherein said label film has a thickness not greater than

approximately 0.9 mil.

1 8. The labeled product package of claim 1 6:

wherein said label film has a thickness of at least

approximately 0.5 mil; and

wherein said label film has a thickness not greater than

approximately 0.8 mil.

1 9. The labeled product package of claim 1 6 wherein said label

film has a thickness of approximately 0.7 mil.

20. The labeled product package of claim 1 6 wherein said indicia

comprises ink.

21 . The labeled product package of claim 1 6 wherein said indicia

comprises hot stamped foil.

22. The labeled product package of claim 1 6 wherein said indicia is

embossed on at least one of said first and second surfaces.

23. A method of making a thin film label, comprising:

applying an adhesive to an elongate web of liner material;

applying label film having a thickness between approximately

0.1 mil and approximately 1 .0 mil to the liner and adhesive to form a

laminate;

selectively applying indicia on the label film;

die cutting the label film to define discrete labels and a matrix

of waste material; and

stripping the matrix of waste material from the laminate so

that only the discrete labels remain on the liner material.

24. The method of claim 23 wherein the step of applying indicia is

by depositing ink on the label film.

25. The method of claim 23 wherein the step of applying indicia is

by embossing the label film.

26. The method of claim 23 wherein the step of applying indicia is

by hot stamping foil on the label film.

27. A method of applying a thin film label to a substrate,

comprising:

providing at least one thin film label on a web of liner material,

the label formed from a label film having a thickness less than

approximately 1 .0 mil;

moving the web of liner material over a peel tip configured to

dispense the label from the web of liner material by pulling the web from a

first side of the peel tip;

driving the web past the peel tip from a second side of the peel

tip, opposite the first side, to control tension in the web;

placing a substrate proximate the peel tip to receive the label

dispensed from the web of liner material as it passes over the peel tip;

controlling the speed of the substrate relative to the speed of

the moving web such that the substrate is moving faster than the dispensed

label; and

wiping the label after it has been received on the substrate to

remove air that may be trapped between the label and the substrate.