Note: Descriptions are shown in the official language in which they were submitted.
9~
~LE~ RELE~SE LABEI, AND ~I~T~IOD OF PRODUCTION
`~ack~ound of the Illvent:ion
In numerous types oE business and industry it is
desirable to produce labels, or nameplates or identification
cards, credit cards, sheets of stationery or the like in
large quantities, in which each item has specific indicia
prlnted thereupon, and in which such indicia or a portion
thereof is different from the indicia printed on any of the
other items. Such printing is usually performed by high-speed
printing apparatus, such as by means o-f ink jet printing or
the like.
It is desirable to produce such labels, nameplates,
identification cards or sheets of stationery or the like on
a continuous web as such items are adhesively attached to the web.
Normally, labels are attached by pressure sensitive
adhesive (PSA) to a silicone coated release paper. Custornarily,
when the pressure sensitive adhesive label is removed from
the silicone coated release paper carrier web, the label is
attached to another surface by means of the tacky adhesive
surface of the label. However, in several types of situations
it is desirable to have both surfaces oE a label and also the
web surface from which the label is rernoved clean and non-tacky.
Such labels are known as clean release labels. Such labels
- are typically variable indicia labels and applications for
such labels are sew-one labels for garments, nameplates, and
identification cards.
One current method of producing clean release labels
is that of reversing the conventional PSA label. That is,
the silicone cGated release ply is die cut to iorm labels
and the PSA coated paper serves as a carrier web or backer
sheet. When these labels are separated from the carrier
~.~74g79
web, the labels are free o~ tacky PSA adhes:ive. ~lowever,
the backer shee~t or ply has tacky PSA adllesive exposecl bo~h
after removal of the matrix (trim portion) and aEter rernoval~
of the label. This creates a messy handling situation due
to the fact that the PSA surface tends to adhere to itseif
and to other surfaces. Furthermore, another disadvantage
is that the silicone release coated label has less than a
satisfactory appearance and an undesirable slippery feeling,
compared with typical label papers.
One effort to overcome the disadvantages of this
reversed PSA clean label product has utilized an adhesive
with controlled adhesion to bond the label ply to the backer
ply. After the labels are die cut and the trim removed,
the labels are ready for customer imaging, followed by removal
of the labels. This approach is deficient because of variations
in adhesive properties. Either the labels have such low
adhesion that they fall off the backer web during processing,
or the adhesion is so high that the labels delaminate and
tear during removal. ~aintaining the desired degree of adhesion
with controlled release adhesives has been most difficult.
Minor differences in process conditions, paper porosity and
wettabilityj and other variables result in excessive differences
in adhesion.
Another approach to construction of clean release
labels to avoid delamination or tearing of the labels during
removal from a carrier web is that of laminating or extruding
polymer films to the back of the label ply or to the front
of the backer ply or both. When these plies are adhered
together by a controlled release adhesive, separation of
the labels from the backer ply is less likely to result in
tearing of the labels or the backer ply. r~he film
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surfaces strengthen ~he paper webs and also pro~lcle a more
uniEorm, less absorbent sur~ace at the interEace with th~
adhesive. ~lowever, this is a costly and complex method, and~
often does not provide the uniform release property desired.
These prior art approaches rely on failure of adhesion
at the interEace between the adhesive layer and the label
surface for controlled release. It is difficult to control
adhesion at the desired level (sufficiently high adhesion
for processing and low enough adhesion for easy removal of
the clean labels) as a result of the critical conditions
at the paper/adhesive interEace.
The present invention takes the novel approach
of utilizing a special class of adhesives which are referred
to herein as fugitive adhesives. These fugitive adhesives
lS exhibit cohesive (i.e., internal Eilm) failure instead of
the usual adhesive/adherent interface Eailure. These cohesive
failure adhesives are relatively weak compositions that adhere
well to paper and similar surfaces. Failure occurs within the
fugitive adhesive film itself when subjected to peeling stresses.
2~ This class of adhesives can be formulated to provide a range
of consistent cohesive strength values. This controlled
cohesive failure concept utilizes water based, solvent based,
or hot melt systems. For a variety of reasons, water based
systems are preferred.
An important feature of fugitive adhesives, as
contrasted with the controlled release adhesives of the prior
art, is that they can be formulated in a systematic manner
to achleve any peel stren~th desired within a broad range.
~ 7~
In Eact, a peel strength can be chosen at a magnitude or
degree between the limits oE product Eunctional:LI:y--that
is, between a peel strength so low that the labèls ~all off
during handling, and a peel strength so high that the labels
cannot be removed without tearing them. Obviously, both
these limits are beyond product functionality, but good
functionality lies somewhere between these limits. Also
important, and one of the truly valuable features of this
invention is that once the desired peel strength is chosen,
~his property can be easily and reliably repeated in batch
after batch by simply controlling the adhesive composition
and the amount of adhesive applied. Thus, product uniforrllity
is assured.
Originally, the class of adhesives, known as fugitive
adhesives, were developed for temporary fastening of carbon
plies to bond paper plies in continuous business forms. This
technique utilized a thin line or a series of small spots
of glue in the margin(s) of the form to maintain the carbon
tissue in register with the adjacent bond ply. In such usage,
after high speed printer imaging, the fugitive
adhesive fails during the decollating operation, without
tearing of the paper or carbon tissue plies.
In regard to this invention, when this cohesive
failure occurs with clean release labels, a thin film of
adhesive remains on the back surface of the clean label and
on the face of the backer ply. However, this adhesive film
has no adverse effect on the appearance or the handling character-
istics of the labels.
~"~ 7~ ~9
The preferred process Eor coating such rwgitive
adhesives is blade coating, which res~lts in ~miform smoothness
of the adhesive film, and provides ease of control of process
variables to obtain the desired adhesion. Slot and other
coating processes can also be used. Paper properties such
as wettability and absorption of adhesive of the label and
backer plies can affect the degree of adhesion. Control
of adhesion also is provided by selection of adhesive
compostions and varying process conditions.
Another embodiment of the clean release label,according
to this invention is a three ply version. Essentially, the
three ply product comprises a two ply clean release label
product with a pressure sensitive adhesive applied to the
back of the backer ply in combination with a silicone coated
release liner. The labels are die cut as two ply labels
which are adhered to the'release liner. The two ply label
}s either manually or m~echanically separated Erom the release
liner and applied i-n register to a business form or other
suitable surface. Following high speed printer imaging or
other operations, the label'can be separated Erom the business
form, leaving a clean exposed surface of the backer sheet
portion of the label bonded to the business form by -the PSA
layer.
Applications for these two and three-ply clean
release labels include garment, shelf, and other labels,
identity, membership, and credit cards, and hidden features
for games, contests, and lotteries.' Frequently, word processing
systems require clean edge letterheads that are free of perfora-
tion ties that result from bursting oE continuous forms.
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~ 9
This clean label approach can be used to provide clean e~lge
letterheads that are releasably bonded to a carrler web.
For some applications, the capability of applying variable
information is an important Eeature. In other instances,
security is an important attribute.
It is an object of this invention to provide such
items as labels, nameplates, or identification cards and
the like which can be firmly adhesively carried by a continuous
web without separating from the web during production and
during storage and shipment, and during customer printing
of variable indicia.
It is another object of this invention to pr,ovide
such a method of production by which the labels, nameplates,
or identification cards or the like can be easily removed
from the web when desired.
It is an object of this invention to provide such
a method by which such items which are removed from a continuous
web are free from tacky or sticky material, and in which
the web from which the labels are removed is also free from
tacky or sticky material. Thus, neither the item nor,the
web is tacky after removal oE the item Erom the web. The
items are thereEore referred to as "clean" labels.
Other objects and advantages of this invention
reside in the construction of parts, the combination thereof,
the method of production and the mode of use, as will become
more apparent from the following description.
~ ~7f~'3~ 9
BrieE Sumnary ;?E th Irventlon
This invention provides an item which Ls referrecl
to as a clean release label which is reaclily removecl
from a carrier sheet or web without tearing or delamination
and which when removed does not have a tacky surface and
in which the surface portion of the web or sheet froln
which the label is removed is not tacky. This ir.vention
also includes a method of production of such clean release
labels.
A plurality of continuous webs of paper-like
materi-al or other material are laminated by adhesive material
which is located therebetween. Preferably at least one
of the webs is paper or paper-like material. The adhesive
material which binds at least two of the webs togetner
has low cohesive strength and bonds readilv to paper
and is non-tacky when dry.
Brief Description of the Views of the Drawings
FIG. 1 is a diagrammatic perspective view illustrating
the method of lamination of a plurality of sheets as the
first step in production of labels in accordance with
this invention.
FIG. 2 is a diagrammatic perspective view illustrating
subsequent steps in production of labels in accordance
with this invention.
FIG. 3 is an enlarged plan view taken substantially
on line 3-3 of FIG. 2.
FIG. 4 is an enlarged plan view taken substantially
on line 4-4 of FIG. 2.
FIG. 5 is an enlarged plan view taken s~lbstantial:Ly
oll line 5-5 o~ FIG. ~.
FI~. 6 is an enlarged plan view Lak~n substantialLy
on line 6-6 of FIG. 2.
FIG. 7 is a fragmentary perspective view oE
a backing sheet and a plurality of labels produced in
accordance with this invention.
FIG. 8 is an enlarged fragmentary sectional
view taken substantially on line 8-8 of FIG. 7.
FIG. 9 is a diagra~matic perspectlve view illustrating
another embodiment in the method of labels in accordance
with this invention.
FIG. 10 is an enlarged fragmentary sectional
view taken substantially on line 10-10 of FI~. 9.
Detailed Description of the Invention
. _
FIG. 1 shows a roll of backing material 16 and
a roll of face material 18, The backing material I6 is
preferably paper or paper-like material, but may be any
other suitable material. In the production of labels,
the face material 18 is usually paper or paper-like material.
~owever, in the production of identification cards or
credit cards or nameplates in accordance with this invention,
the face material 18 may be other than paper or paper-
like material. For exainple, the face material 18 may
be a flexible plastics or metallic material or -the like.
The face material can be back printed with appropriate
register marks if the application requires that the label
be printed on both sides.
The backing material 16 e~tencls in a we~ from
the roll thereoE as the~ back:ing maLerial 16 en~clges severaL
rollers 20. The backing mater-ial 16 then engages a clrum
24 which has a blade 26 in juxtaposition therewit~. The
S blade 26 and the drum 24, with the backing material 16,
contain a quantity of fugitive glue 30, which is thus
coated upon the backing material 16 as the web thereof ~
travels around a portion of the drum 24. The web of backing
material 16 then extends from the drum 24 to a position
between a drum 34 and a drum 36.
Th~ face material 18 extends from the roll thereof
in a web which engages rollers ~0. The Eace material
18 extends to a position between the drums 34 and 36.
As the backing material 16 and the face material 18 come
into engagement one with the other and travel between
the drums 34 and 36, pressure is applied to the backing
material 16 and to the face material 18. Thus, the backing
material 16 and the face material 18 are adhesively attached
together and laminated by the coating oE fugitive adhesive
30 which is applied to the backing material 16 at the
drum 24.
The laminated backing material 16 and the face
material 18 extend as a web from the drums 34 and 36 to
a drum 44 and encompass a portion of the drum 44 and then
travel through an oven 50 within which the fugitive glue
30 is dried. The web of backing material 16 and the face
material 18 is shown extending from the oven 50 and engaging
rollers 56 as the laminated web e~tends to a rewind drum
60 and is wound thereupon.
~.~ 74 ~
The laminatecl web o:E the backlng rnaterial 16
and the face material 18, :in its rolled cond.iti.ot- ~Ipon
~he drum 60, may then be stored for future use or transported
to another lo~ation for further use.
In the final steps of procluction of labels according
to t:his invention, the laminated web of backing material
16 and face material 18 is unwound from the drum 60, as
illustrated in FIG. 2. The web is shown extending from
the drum 60 to engagement with a roller 64. The web then
extends to print apparatus 68 which applies ink 70 to
the face material 18 in a desired configuration, as the
web travels between drums 72 and 74.
The web then travels over a roller 78 and through
a drier 80, then around rollers 84, 86, and 88 to die
cut cylinders 90 and 92. As the web travels to the die
cut cylinders 90 and 92, the face material 18 may appear
generally as illustrated in FIG. 3, as the face material
18 carries printed indicia 94 which was applied thereto
by the print apparatus 68 in selected spaced-apart areas
of the face material 18.
The die cut cylinders 90 and 92 sever the face
material 18~ As the web travels from the die cut cylinders
90 and 92, the face material 18 of the web appears generally
as illustrated in FIG. 4, with severance lines 96 dividing
25 the face material 18 into distinct label por-tions L00 ^
and a matrix portion 104. The die cut cylinders 90 and
92 also apply perforation fold lines 134 tG the backing
material 16.
The web then travels in engagement with rollers
106 and 108 and then to a roller 112 at which the matrix
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po-rtion 10~ oE the face material 18 is sepa~ated Erom the
web, and the matrix portion lOl~ appears substantially as
illustrated in FIG. 5. The matrix portion 104 is wound upon
a drum 116.
The backing material 16 with the label portions
100 carried thereby travels from the roller 112 to a roller
120 and the backing material with the label portions 100
thereupon has an appearance generally as illustrated in FIG.
6.
The web consisting of the backing material 16 with
label portions 100 carried thereby, may then be folded into
a fan-fold stack arrangement 130, along the perforation fold
lines 134, as illustrated in ~IG. 2. The fan-fold stack
130 may be stored or transported to another location for
use of the label portions 100.
A label portion 100 may be removed from the backing
material 16 in the manner illustrated in FIG. 7 by a peeling
action. The label portion lOO has no tacky sur~ace and the
portion of the backing material 16 from which the label portion
100 is removed is not tacky. The label portion 100 may thus
be attached to a garment of clothing or to another element
as the label portion is sewed or otherwise attached to the
other element.
The label portion 100 may comprise an identification
member such as a nameplate, credit card or identification
card or the like.
A suitable fugitive adhesive 30 r.lay be chosen from
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~7~9 ~ 9
a series of blends of polyvinyl acetate and poLycthylene
emulsions. This series is Eormulated by varying the ra~io
of these two emulsions. Such a series is available from
H. B. Fuller Company. Representative members of the series,
designated by the manufacturer~s code numbers, are W3836-XPN,
CX-3879, CX-3879X, and CX-3880. The peel strength of this
series progresses from lowest to highest in the order listed.
The preferred member of the series is CX-3879~. Convenient
physical properties for such an adhesive are: viscosity 3500
to 4500 centipoises at 30 degrees centigrade, specific gravity
0.98 to 1.15 grams per cubic centimeter, oven dry solids
content of 43 to 58%, and pH from 4.5 to 8.5.
The adhesive 30 is applied by the blade 26 or by
any other suitable process at a rate of about 3.0 to 22.0
grams per square meter, preferably 3.0 to 12.0 grams per
square meter, dry weight.
The fugitive adhesive has a low cohesive strength,
bonds well to paper, and is non-tacky to the touch when dry.
It also provides uniform non-fiber tea-~ing clean release
from paper. Preferred release levels may be in the range
oE 100 to 500 grams per 5 centimeters of width, but the preferred
range is 150-300 grams per 5 centimeters of width, although
higher and lower values are functional. The release test
is conducted at 90 degree peel at 1500 centimeters per minute,
as the backing material 16 is pulled from the face material
18. A suitable adhesive may be generally identified as one
in which cohesive failure occurs as a label portion 100 is
peeled from the backing material 16. Cohesive failure is
defined as that which occurs within the layer of adhesive
~ 3~
30, rather than failu-re which would OCC~IL- at t:he interface
between the label portion lO0 and the aclhe~ive 30 or which
would occur ~t the interface between the backing material
16 and the adhesive 30.
It is to be understood that the laminated web of
the face materlal 18 and the backing material 16 does not
need to be wound into a roll such as on the drum 60, as
illustrated. The laminated web of -the face material 18 and
the backing material 16 may travel directly Erom the oven
50 to the print apparatus 68. If printing upon the Eace
material 18 is not desired, the laminated web of the face
material 18 and the backing material 16 may travel directly
from the oven 50 to the die cut cylinders 90 and 92.
FIG. 9 illustrates another method of prod~ction
of clean release labels in accordance with this invention.
As shown in FIG. 1 and discussed above, a web of backing
material 16 is laminated by fugitive adhesive 30 to a web
of face material 18 and is wound upon a drum 60. In the
method illustrated in FIG. 9, the laminated web is unwound
from the drum 60, and travels aroilnd the roller 64, and then
travels through the print apparatus 68, as shown in FI5.
9. The'laminated web then travels through the drier 80,
around the roller 84 and then travels to the roller 86.
FIG. 9 also shows a carrier web 140 which is coated
with silicone release material or the like.
At the roller 86 the laminat'ed web of face material
18, wi'th the backing material 16 laminated therewith, becomes
laminated with the release coated carrier web 140. The ,,
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car-rler web 140 travels Erom a roll thereof shown in F-LG.
9, clnd moves to a coating station 146 at which pressure sensi-
tive bonding adhesive 144 is applied to the lower surface
of the carrier web 140. Thus, at the ro]ler 86, as the web
140 engages the laminated web of face material 18 and backing
material 16, the two webs are adhesively attached together.
The laminated webs 18, 16 and 140 then travel to
the die cut cylinders 90, at which label portions 200 are
formed. A matrix 150 is then removed from the webs 18, 16,
1~ and 140 at the roller 112, and the carrier web 140 carries
the label portions 200 from the roller 112. The carrier
web 140 may then be folded, as illustrated in FIG. 9, or
wound into a roll. The lamination of web 140 with laminated
webs 16 and 18 may take place as a separate operation and
then be printed and die-cut later.
The carrier web 140, as illustrated in FIG. 10,
thus has the layer of pressure sensitive adhesive 144 which
firmly attaches the backing material 16 to the release coated
web 140. The fugitive adhesive 30 attaches the backing material
' 16 to the face material 18. Thus, the label portion 200
is carried by the carrier web 140.
The label portion 200 may be removed with its pressure
sensitive adhesive coating from the carrier web 140 and adhesively
attached to another surface. Then, after customer imaging,
the face material 18 may be removed from the backing material
16, as cohesive failure occurs within the Eugitive adhesive
30. The face material 18 thus forms a clean label or nameplate
or card or the like.
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3 i'9
Thus, i~ is understood that the proces~ o:E this
invention is capable oE producing items in the ~orm oE clean
labels, or tags or cards, or nameplates, or sheets of
stationery, or the like at rèlatively low costs. Due to
the fact that neither the item nor the backing rnaterial is
tacky, the label and the backing material can be easily and
readily handled for any desired purpose.
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