U.S. patent number 3,581,690 [Application Number 04/785,443] was granted by the patent office on 1971-06-01 for crown type closure with double removable liner unit enclosing trapped indicia and method of manufacture.
This patent grant is currently assigned to Zapata Industries Inc.. Invention is credited to G. Claudio Zapata.
United States Patent |
3,581,690 |
Zapata |
June 1, 1971 |
**Please see images for:
( Certificate of Correction ) ** |
CROWN TYPE CLOSURE WITH DOUBLE REMOVABLE LINER UNIT ENCLOSING
TRAPPED INDICIA AND METHOD OF MANUFACTURE
Abstract
The closure cap or crown for bottles disclosed, comprises a
crown shell having a print covered by a size coat, a removable
liner unit including a first removable liner coating in the shell
over the size coating carrying printed indicia, such as a question,
and being either transparent or opaque, a second liner coating of
transparent plastic material covering the first liner coating and
the printed indicia thereon, and an annular sealing ring at the
periphery of the second liner coating.
Inventors: |
Zapata; G. Claudio (Mexico
City, MX) |
Assignee: |
Zapata Industries Inc.
(Frackville, PA)
|
Family
ID: |
25135531 |
Appl.
No.: |
04/785,443 |
Filed: |
December 16, 1968 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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731852 |
May 24, 1968 |
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Current U.S.
Class: |
413/9;
413/19 |
Current CPC
Class: |
G09F
3/18 (20130101); G09F 3/00 (20130101); G09F
23/00 (20130101); B65D 41/12 (20130101); B65D
51/245 (20130101); B65D 2203/00 (20130101); G09F
2023/0025 (20130101) |
Current International
Class: |
G09F
3/08 (20060101); G09F 23/00 (20060101); B65D
41/12 (20060101); B65D 41/02 (20060101); G09F
3/18 (20060101); B65D 51/24 (20060101); G09F
3/00 (20060101); B21d 051/46 () |
Field of
Search: |
;113/121A,121AA,121B,121F,116BB,80,8C,8D,8DA ;215/39,40 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Herbst; Richard J.
Assistant Examiner: Keenan; Michael J.
Parent Case Text
Cross-Reference to Related Application
This application is a continuation-in-part of the applicant's
pending U.S. application Ser. No. 731,852, filed May 24, 1968, now
abandoned.
Claims
I claim:
1. In a method of making container closure caps of the type
including a rigid shell provided with an adherent size coating on
its inner surface, and a removable plastic sealing liner unit
releasably secured to the size coating in the interior of the rigid
shell, wherein the improvement comprises the steps of applying and
curing a size coating on one surface of a sheet of material for
making a multiplicity of closure caps, applying and curing a
plastic coating film over said size coating, printing indicia on
the film on said sheet at the locations for the caps, curing the
printed indicia on said film, punching the closure caps from the
sheet, applying and curing a transparent plastic coating film and
integral sealing ring over the printed indicia and on the film on
which it is located in each cap and adhering it thereto thereby
trapping the printed indicia between said films, whereby caps are
produced having readily removable liner units comprising indicia
trapped and protected between the two films.
2. A method as claimed in claim 1, including the step of curing the
size coating by baking it at a temperature of from 395.degree. to
405.degree. F. for a period of about 10 minutes to give its outer
surface of low adherent quality with respect to the plastic coating
applied thereover when cured.
3. A method as claimed in claim 2, wherein the plastic coating
applied over the cured size coating is baked and cured at a
temperature of from 300.degree. to 345.degree. F. over a period of
about 10 minutes.
4. A method as claimed in claim 1, including the step of printing
indicia on said surface of the sheet of material at the locations
of the shells prior to the step of applying the size coating, and
wherein the plastic coating film over the size coating and over the
said indicia is opaque and nonadherent to said size coating,
whereby said indicia is made visible only after removing the liner
units from the completed caps.
5. A method as claimed in claim 1, including the step of applying a
ring of nonadherent material on the cured size coating directly
beneath the position of the sealing ring.
6. A method as claimed in claim 5, wherein the ring or low adherent
material is in the form of printed indicia made visible only after
the liner unit is removed from the cap.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in bottle cap closures,
particularly crown-type closures provided with a removable liner
unit of plastic material carrying selected printed indicia and
seated over an interior size coating of the closure.
2. Description of Prior Art
Prior disclosures relating to the above subject comprise U.S. Pat.
Nos. 3,233,770, 3,361,281, and 3,257,021. These patents were
granted recently, and the first discloses a crown-type closure
provided with a removable liner which is arranged to carry printed
indicia which may be mailed out by a customer to the distributor or
manufacturer. In this instance the liner is a clear plastisol
material. The crown closure is provided with a coating of lacquer
and indicia are printed on this lacquer in the interior part of the
closure. Subsequently, the liner is applied over the printed
indicia material. In this construction the relationships are such
that the lacquer coating is nonadherent to the liner, and the
printing is selectively adherent to the liner, so that it is
removed from the closure with the removable liner. The patent
describes specific vinyl chloride polymer plastisols and
plasticizers and other materials which may be used in forming the
films and coatings of the present invention.
The third patent referred to above has a disclosure very similar to
the first. In this instance the printed indicia are printed on the
lacquer of the closure and covered over with a transparent elastic
cushion liner, so that the printing is visible therethrough when
looking into the closure. The liner may be peeled from the closure
and carry the printed indicia adhering thereto because of its
preferential adherence to the liner rather than the lacquer on the
closure. To begin with, the indicia is adherent to both the lacquer
and the liner but the adhesion between the indicia and the liner is
said to be greater than that between the indicia and the
lacquer.
In these prior disclosures the printing material used to form the
indicia are said to reduce the adhesion between the liner and the
lacquer over a considerable portion of the area of the closure.
Overbaking of the lacquer is also disclosed.
The attempt to remove the printed indicia in the prior art
disclosures, along with the removable liner, is in many instances
only partially successful. Sometimes there is only a partial
transfer of the indicia to the liner when it is removed from the
closure and in a number of instances a poor or illegible image or
printing results. According to the present invention, the removable
liner unit provides the indicia or image in the perfect condition
in which it is printed. This is achieved by providing a first
plastic coating over the lacquer or sizing, and any printing
thereon, on the interior of the shell under conditions so that it
is readily removable. Next, this first coating or film is printed
by the various procedures described in the above patents to provide
the desired indicia. After printing the first film, a second film
is applied to the first film over the printing, so that the latter
is trapped between the two films and kept in perfect condition
until, during and after the liner unit is removed from the
closure.
One of the objects of the present invention is to achieve good
promotional features without sacrificing the functional properties
of a plastic lined crown. An "easy-removal" liner manufactured by
sacrificing the normal adhesion between the liner and crown shell
frequently results in blister formation in the central panel caused
by gas diffusion from the bottle. Such blisters are objectionable
in appearance and can lead to a distortion of the gasket ring and
subsequent loss of pressure retention.
In prior attempts to achieve easy removal by using the thumbnail to
remove the plastic liner from the sheet, the above functional
features were sacrificed by either providing a low order of
adhesion of the liner to the shell (U.S. Pat. No. 3,257,021) or
only adhering the liner in selected areas (3,233,770 ). In each
case, the reduction in adhesion between liner and shell to
accomplish "easy removal" results in an occasional loose liner in
the shell, blister formation, gas leakage, or difficulty in removal
by thumbnail because the reduction in adhesion is difficult to
control.
SUMMARY OF THE INVENTION
The present invention comprises a container closure provided with a
size coating which may be printed, and a removable liner unit as
described above, which includes first and second films or coatings
between which indicia are trapped. This liner is prepared and
formed in such a way along with an annular seal that it provides
protection for the goods sealed in the container and at the same
time provides a readily removable liner unit after the closure is
removed from the container.
In accordance with the invention, large tinned steel sheets of the
type used in this art, shown and described in U.S. Pat. No.
3,257,021, are printed then coated with a low solids size coat.
This is the initial lacquer coating of the large tinned sheets,
after which that coating is baked on at a temperature to give good
adhesion to the tinned sheet and printing. This size coating, at
the positions within the sealing rings, is now advantageously
printed with some message, such as a question or answer, for
example with printing ink material.
As an additional novelty to aid in easy removal of the liner unit
without sacrificing functional properties, a ring of clear ink can
be printed on the interior size coating around the gasket areas to
reduce adhesion of the liner unit to the sizing, thus facilitating
easy removal with an average fingernail. This ring of clear ink may
be used or not depending on the ease of removal required.
The second coating referred to as the first film of the removable
liner unit is applied over the large sheets on the size coating and
or the ring of clear ink. This coating is preferably a polyvinyl
chloride organisol applied to produce a heavier film weight than
the size coat. It may be transparent but in some instances it is
made of opaque material. The next step is the printing of an image
or indicia on the large sheet in the positions of the respective
closures to be stamped from the sheet. This goes on the second
coating and the printing is preferably effected by a printing ink
of known type applied in various ways, such as by screen or
lithographic press, and may be trail coated with the third coating,
or a third, transparent coating, may be applied over the second
coating and adhered to it. Each coating is heated or baked before
the application of the next coating, and the third coating is also
baked.
The conditions are such as to control the adhesion, particularly
between the size coating and the second coating. If the third
coating is applied, the large sheets are subjected to the usual
punching operation to cut out and form the crowns, each of which
would carry the three coatings with the various indicia and or the
clear ink ring. In this case the crowns are finally provided with
an annular sealing gasket of a foamed or solid polyvinyl chloride
plastisol material of known type, and the annular seals are baked
and cured in an oven. Instead of applying the third coating as
above, an advantageous structure is provided by simultaneously
applying a third coating and annular sealing ring. This third
coating and sealing ring are applied to the punched out crowns by a
cold punch die operation on hot plastic material. No curing is
thereafter necessary. The plastic material used is such that the
area inside the sealing ring is transparent.
In carrying out the main features of the invention some
modifications may be made, for example, the crowns may be punched
out following the printing of the indicia on the second coating
after which a transparent film is provided, for example, by
spinning in a center panel section to cover a limited area short of
the edge of the panel. An annular seal may then be applied in each
closure, so that it covers the peripheral edge of the second film
and is adhered to the first film of the removable liner.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawing provided herewith as a part of this application
illustrates the invention in connection with two embodiments.
In the drawing:
FIG. 1 comprises an enlarged broken sectional view through a
crown-type closure comprising one embodiment having a removable
liner with trapped indicia over a ring of release material,
although it may be without the ring of release material, and an
annular seal constructed and arranged in accordance with the
invention;
FIG. 2 is a view similar to that of FIG. 1 showing a second
embodiment provided with a removable liner, located over indicia
under the size coating, and containing trapped indicia in which the
transparent third film and annular seal are integral; and
FIG. 3 is a plan view showing a removed liner message unit and
crown according to FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In both FIGS. 1 and 2 the crown closure or bottle cap comprises a
rigid tinned steel plate member 10. The outside of the crown
closure is provided with a size lacquer coating 12 called a
modified vinyl size coating of known type on which the usual
exterior printing is applied. Inside the crown there is also a
modified vinyl or primer size coating 14 covering the entire
interior surface of the shell including the corrugated skirt
16.
In FIGS. 1 and 2 the various coatings are cut back to expose a part
of the coating beneath. The removable liner unit is applied over
the size coating 14 and consists of a coating 18, a somewhat
heavier coating than that of the coating 14. These coatings may be
applied over the entire interior area of the crown, including the
corrugated skirt portion 16. The coatings 14 and 18 are applied
uniformly over the large sheets before the crowns are punched
therefrom. However, the coating 18, of similar material to the
coating 14, is applied in such a manner as to apply limited
adhesion to the size coating 14.
The limited adhesion of the coating 18 to the size coating 14 can
be greatly reduced by applying a ring of clear ink 15 to the size
coating 14 at the position below the sealing ring gasket of the
crown. This reduces the adhesion under the gasket area and thus
facilitates easy removal with the average fingernail. The clear ink
used may comprise a property which is designed to cause the ink to
adhere selectively to the size coating 14 only. Easy removal may
also be effected by providing a ring of printed indicia at the
position of the ring layer 15, using the same type of ink but
preferably one which is not clear but which is made visible such as
an answer to a question when the removable liner unit is finally
removed from the crown.
Additional printing 19 is applied to the tinned steel plate 10,
before applying the size coating 14, in the area inside that of the
ring 15. This printing may be an answer to a question and as
illustrated comprises the answer shown in FIG. 3, FIG. 1 showing
the lettering "THE ST." The lettering may be in a desirable color
and since the printing is trapped under the size coating it will
not adhere to the coating 18. In this case the coating 18 would be
made of opaque material, so that the printing under the interior
area of the transparent size coating will only be made visible when
the liner unit is removed. This is described more in detail in
connection with FIG. 2.
Following the application of the printing 19, coating 14, the ring
15 and the coating 18, the large sheets are printed at the
locations of the crown panels to provide the desired indicia or
message on the panel section of the coating 18. Such indicia is
indicated at 20 which for purposes of illustration may be a
question as in FIG. 3, or comprise the letters "SODA" which may be
only a part of the message.
In the embodiment in FIG. 1 the crowns may be punched from the
large sheet after applying the printing 20 and thereafter each
crown is provided with a transparent liner film 22 by spinning the
crowns and applying a blob of polyvinyl chloride plastisol or
organisol material to the center of the panel portion so that it
spreads out thinly to the periphery of the panel portion 24 of the
crown. This film coating 22 completely covers the printed indicia
20 and its periphery is adhered firmly to the coating 18. Finally,
the crowns are slowly rotated while a sealing ring 26 is applied
over the peripheral portion of the film 22 above the element 15.
The various coatings and the sealing ring 26 are subjected to
baking operations described more in detail hereinafter. The
transparent coating 22 may extend completely to the skirt of the
crown or only to a position so that its edge is well covered by the
sealing ring 26 or as shown in FIG. 1. The film or coating 22 may
be spun in, or applied as spots by screen printing, or spot coating
on the large sheet before punching.
The embodiment illustrated in FIG. 2 may include elements
corresponding to the elements shown in FIG. 1 up to and including
the printed indicia material 20' on the coating 18. In this view,
the sealing ring and the center panel coating are applied as a
single integral element which comprises a central transparent film
panel 22' molded integrally with a ring gasket 26' . The material
used in making these two elements comprises a dry blend gasket
molding liner material of known type supplied to the crowns hot and
molded with a cold die. The integral element includes a peripheral
portion 28 immediately outside the gasket 26' and this portion
together with the area beneath the gasket is firmly adhered to the
coating 18.
In the construction shown in FIG. 2 an adhesion reducing layer 15'
similar to the layer 15 of FIG. 1 can be provided on the size
coating 14 beneath the area covered by the sealing ring 26' and the
peripheral portion 28. Printed indicia 21, illustrated by the
letters C and O are also provided on the layer 15' to form an
entire ring of indicia which is also of adhesion reducing material.
This indicia is made visible when the removable liner is taken from
the crown.
The crown and removable liner shown in FIG. 2 are provided with the
indicia set out in FIG. 3. For example, the indicia 20' is printed
on the coating 18 within the panel area inside the ring 26' . Since
the layer 22' is transparent the question of the indicia 20' is
plainly visible before the removable liner is taken from the crown.
In this instance the coating 18 is preferably opaque so that the
answer of the indicia 30 located under the size coating 14 is not
disclosed until the removable liner is pulled out of the crown.
The removable liner shown in FIG. 3 may have the structure
illustrated in either FIG. 1 or FIG. 2, but FIG. 3, for purpose of
simplification, does not include a showing of the element 15 of
FIG. 1 or the elements 15' or 21 of FIG. 2.
In producing the combination illustrated in FIGS. 2 and 3, the
indicia or answer 30 is printed on the tinned sheets 10 and cured
before applying the size coat 14. Following this, the coating 18 is
applied over the size coating 14 and the elements 15' and 21
thereon. This coating is cured, after which the indicia of the
question 20' is applied, following which the large sheets are
passed through a curing oven at from 300.degree. to 335.degree. F.
for a period of about 10 minutes. The coating 18 is preferably
opaque, so that the answer indicia 30 on the tin is not visible or
learned until the removable liner is taken from the crown.
The layer 22' and the ring seal 26' are applied over the question
indicia 20' in the manner described above. It is to be understood,
of course, that instead of the integral layer 22' and ring 26' ,
one may use the coating 22 and sealing ring 26.
EXAMPLE
The large tinned steel sheets, from each of which a considerable
number of crowns are finally punched (as in U.S. Pat. No.
3,257,021) are printed with indicia 19 or 30, later coated with a
commercial polyvinyl chloride liquid sizing material following
which the large sheets are baked in an oven at a temperature of
from approximately 395.degree. to 405.degree. F. for a period of
approximately 10 minutes. The coating 14 may amount to
approximately 4 to 8 mg. per 4 square inches of the sheet and the
baking cures and hardens the size coating 14, so that it is adhered
firmly to the tin coat of the steel sheets and yet gives an outer
surface which has limited adhesion characteristics with respect to
subsequent coating 18, when coating 18 is baked at temperatures
below the fusion point of the two coatings.
Prior to applying the coating 18, the sizing coat 14 can receive
the ring of low adhesion material 15 or 15' and printing 21 is
applied to the ring or band 15' . The lacquered or sized sheets are
thereafter coated with the plastic film 18, which has a high solids
content commercial coating material sometimes referred to as
polyvinyl chloride organisol, examples of which are given in the
above patents. This coating amounts to 25 to 70 mg. per 4 square
inches and is baked on in an oven at a temperature of from
325.degree. to 345.degree. F., preferably 335.degree. F. In the
oven the sheets are passed along at a rate such that a baking time
of about 10 minutes is obtained and the temperature and time of
baking are adjusted to provide some adhesion to the sizing coat 14,
but an adhesion which is limited. A good film 18 is obtained with
20 to 25 mg. per 4 square inches.
The next step of the process is that of printing an indicia message
or question on the exposed surface of the cured coating 18. The
indicia 20 and 20' are applied in a known manner by the use of a
suitable printing ink material, such as disclosed in said patents,
preferably by an offset litho method. The printing of an entire
sheet at a time with the multiplicity of locations is accomplished
in a very accurate manner by this method. However, the printing may
be accomplished by ordinary offset procedure, lithographic gravure,
silk screen or flexographic methods. The printed sheets are baked
at a temperature of from 295.degree. to 305.degree. F. for a period
of about 10 minutes to fix and cure the printing material. Printing
19 and 30 may be cured by the same procedure before applying the
size coating 14.
In accordance with the embodiment shown in FIG. 1, the fourth step
is the provision of a solid coating film 22 over the indicia 20 and
the remainder of the coating 18 to the extent shown. This film is
applied either to the sheets or to the individual crowns after they
are punched from the sheets as described above.
The transparent film coating 22 may be applied to the individual
crowns over the indicia 20 and the coating 18 to the extent shown
by depositing a blob of polyvinyl chloride organisol into each
crown and rotating it until the coating 22 spreads out. The coating
22 either on the sheets or the crowns is baked at a temperature of
from 305.degree. F. to 325.degree. F., preferably 315.degree. F.
for a period of about 10 minutes and adhered to the coating 18. The
plastisol used to form the film 22 produces a clear film through
which the question or other indicia 20 are visible.
Finally, the foamed plastisol gasket 26 is applied in each crown on
top of and adhered to the peripheral portion of the film 22. The
material used for this gasket is a commercial product and is
applied in the ring shape, in a known manner, while slowly rotating
the crown. The gasket is baked in the crown at a rather high
temperature, that is, 390.degree. F. to 400.degree. F. for a period
of 1 minute. Known types of baking ovens may be used in effecting
the various baking steps.
The procedure followed with respect to the embodiment shown in
FIGS. 2 and 3, after the indicia are printed on the film 18
comprises the use of a cold-molded liner comprising the transparent
film layer 22' and the raised ring gasket 26' which are molded in
one piece. The liner may be cold die molded from a hot molten
pellet of commercial polyvinyl chloride liner material. The heat in
the molten pellet being molded, causes fusion between the formed
liner material and the film 18, instantaneously, that is, during
only a fraction of a second.
It is to understood that the film 22' and the integral ring gasket
26' are one piece, and may be applied in a known manner by the use
of a cold molding plunger pressed downwardly on a suitable quantity
of hot molten commercial polyvinyl chloride liner material, which
may originally be a dry blend.
In accordance with the invention the separation of the film 18 from
the size or lacquer coating 14, and the elements 15, 15' and 21
when the removable liner unit is removed from the closure, is
achieved because of the control of adhesion. The coating 14 is a
vinyl size coating as used in the industry, which adheres well to
the tin plate and elements 19 and 30 under the conditions described
in the above example, while the coating or film 18 is of the
modified polyvinyl organisol type, or dispersion of polyvinyl
chloride in a plastisol with other modifying resins. This material
has the property to develop only a physical adhesion to the vinyl
size coating and little if any adhesion to the elements 15, 15' and
21, under the baking conditions described in the above example. It
is baked at a temperature below 350.degree. F. at which it does not
develop maximum chemical adhesion with the size coating or the
mentioned elements. The size coating 14 is baked at a normal baking
temperature which gives good adhesion to the tin plate and provides
low adhesion surface for the coating 18.
When a bottle cap, for example, is removed from a beverage bottle
by a customer, the liner unit is readily removable from the size
coating 14 by breaking the thin film 18 partly around the outside
of the gasket 26 along the dotted line a-a. This may be
accomplished readily by a fingernail or pen knife. When the liner
is lifted at one point, a separation occurs between the film
coating 18, the size coat 14 and elements 15, 15' and 21. Since the
printed question or message indicia 20 or 20' is located on the
film 18 and trapped by the film 22, the indicia is removed with the
liner message unit, which has been sealed away from the contents of
the container, the lacquer coating 14 and the printing 19 and
30.
In FIG. 2 the message liner unit is readily removable by running a
fingernail or a pen knife along the dotted line a-a and edge of
film portion 28. This severs the film 18, so that the sealed
message or question unit is readily removable from the size coating
14 and the elements 15' and 21.
The closures or crowns of the present invention may be of the
press-on or screw-on type for use on soft drink or other bottles,
jars and other containers.
An excellent product can be made without making use of the size
coating 14. Therefore, the coating 18 may be applied directly over
the indicia 19 or 30 as well as the elements 15, 15' and 21, which
would be applied directly to the tinned surface of the steel plate
10. In this construction the printing 19, 21 and 30 may be omitted
so that a single message unit is provided which is sealed between
the films 18 and 22 or 22' .
* * * * *