U.S. patent application number 09/764478 was filed with the patent office on 2002-11-07 for pressure sensitive adhesives with a fibrous reinforcing material.
Invention is credited to Everaerts, Albert I., Zhou, Zhiming.
Application Number | 20020164446 09/764478 |
Document ID | / |
Family ID | 25070845 |
Filed Date | 2002-11-07 |
United States Patent
Application |
20020164446 |
Kind Code |
A1 |
Zhou, Zhiming ; et
al. |
November 7, 2002 |
Pressure sensitive adhesives with a fibrous reinforcing
material
Abstract
This invention is directed to a fiber reinforced adhesive
composition comprising a pressure sensitive adhesive matrix and a
fibrous reinforcing material within the pressure sensitive adhesive
matrix. The adhesive composition has a yield strength and a tensile
strength. The tensile strength is at least about 150% of the yield
strength. Generally, the adhesive composition exhibits these
properties at least 50% elongation when measured according to ASTM
D 882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute).
Inventors: |
Zhou, Zhiming; (Woodbury,
MN) ; Everaerts, Albert I.; (Oakdale, MN) |
Correspondence
Address: |
Attention: Colene H. Blank
Office of Intellectual Property Counsel
3M Innovative Properties Company
PO Box 33427
St. Paul
MN
55133-3427
US
|
Family ID: |
25070845 |
Appl. No.: |
09/764478 |
Filed: |
January 17, 2001 |
Current U.S.
Class: |
428/40.1 |
Current CPC
Class: |
Y10T 428/1452 20150115;
Y10T 428/1481 20150115; C09J 11/08 20130101; Y10T 428/1405
20150115; Y10T 428/28 20150115; C09J 2301/302 20200801; B33Y 80/00
20141201; Y10T 428/24942 20150115; C09J 133/06 20130101; C09J
2433/00 20130101; C09J 2301/308 20200801; C09J 7/10 20180101; C08L
2666/02 20130101; Y10T 428/1486 20150115; Y10T 428/1462 20150115;
Y10T 428/14 20150115; C08L 2205/16 20130101; C09J 7/38 20180101;
A61L 15/58 20130101; C09J 133/06 20130101; C08L 2666/02
20130101 |
Class at
Publication: |
428/40.1 |
International
Class: |
B32B 007/06 |
Claims
What is claimed is:
1. An adhesive composition comprising a pressure sensitive adhesive
matrix; and a fibrous reinforcing material within the pressure
sensitive adhesive matrix; wherein the adhesive composition has a
yield strength and a tensile strength, and wherein the tensile
strength is about 0.7 MPa or greater, and at least about 150% of
the yield strength.
2. The adhesive composition of claim 1 wherein the fibrous
reinforcing material comprises substantially continuous fibers.
3. The adhesive composition of claim 1 wherein the adhesive
composition has an elongation at break of at least about 50%.
4. The adhesive composition of claim 1 wherein the adhesive
composition has an elongation at break of at least about 300%.
5. The adhesive composition of claim 1 wherein the adhesive
composition has a tensile strength of about 0.8 MPa or greater.
6. The adhesive composition of claim 1 wherein the adhesive
composition has a yield strength of no less than about 0.1 MPa.
7. The adhesive composition of claim 1 wherein the adhesive
composition has a yield strength of no less than about 0.2 MPa.
8. The adhesive composition of claim 1 wherein the pressure
sensitive adhesive comprises about 60 to about 95 weight % of the
adhesive composition and the reinforcing material comprises about 5
to about 40 weight % of the adhesive composition.
9. The adhesive composition of claim 1 wherein the pressure
sensitive adhesive comprises about 70 to about 95 weight % of the
adhesive composition and the reinforcing material comprises about 5
to about 30 weight % of the adhesive composition.
10. The adhesive composition of claim 1 wherein a ratio of the
reinforcing material melt viscosity to the pressure sensitive
adhesive melt viscosity is about 0.5 to about 1.2.
11. The adhesive composition of claim 1 wherein the fibrous
reinforcing material comprises at least one fiber having a diameter
of less than about 5 micrometers.
12. The adhesive composition of claim 1 wherein the fibrous
reinforcing material comprises at least one fiber having an aspect
ratio of greater than about 1000.
13. The adhesive composition of claim 1 wherein the pressure
sensitive adhesive comprises a pressure sensitive adhesive based on
at least one of a natural rubber, synthetic rubber, styrene block
copolymer, polyvinyl ether, poly(meth)acrylate, polyolefin,
silicone or combinations thereof.
14. The adhesive composition of claim 1 wherein the pressure
sensitive adhesive comprises a polymer derived from at least one
alkyl (meth)acrylate ester monomer selected from isooctyl acrylate,
2-ethyl-hexyl acrylate, and n-butyl acrylate; and at least one
co-monomer selected from acrylic acid and acrylamide.
15. The adhesive composition of claim 1 wherein the reinforcing
material comprises an elastomer having a yield strength no greater
than about 20 MPa and a tensile strength of at least about 150% of
the yield strength.
16. The adhesive composition of claim 1 wherein the reinforcing
material comprises a semi crystalline polymer.
17. The adhesive composition of claim 1 wherein the reinforcing
material has a melting point greater than about 70.degree. C.
18. A substrate at least partially coated with the adhesive
composition of claim 1.
19. The substrate of claim 18 wherein the substrate comprises a
release liner.
20. A tape comprising a backing having a first and second side; and
the adhesive composition of claim 1 coated on at least a portion of
the first side of the backing.
21. A tape comprising a backing having a first and second side; and
the adhesive composition of claim 1 coated on at least a portion of
the first side of the backing and, optionally, on at least a
portion of the second side of the backing.
22. A stretch removable article comprising the adhesive composition
of claim 1.
23. The adhesive composition of claim 1 wherein the adhesive
composition is stretch removable from a substrate.
24. An adhesive composition comprising a pressure sensitive
adhesive matrix; and a fibrous reinforcing material, having a
melting temperature of no less than about 70.degree. C., within the
pressure sensitive adhesive matrix; wherein the adhesive
composition has a yield strength and a tensile strength, and the
tensile strength is at least about 150% of the yield strength.
25. A method for making a fiber reinforced adhesive composition
comprising (a) forming a mixture comprising a pressure sensitive
adhesive with a reinforcing material capable of forming fibers when
subjected to an elongating shear force; and (b) subjecting the
mixture to the elongating shear force to form the adhesive
composition of claim 1.
26. The method of claim 25 further comprising quenching the
adhesive composition.
27. The method of claim 25 wherein the reinforcing material is
elastomeric.
28. The method of claim 25 wherein the reinforcing material is
semi-crystalline.
29. A medical article comprising the adhesive composition of claim
1.
30. The medical article of claim 29 which is in the form of a wound
dressing, surgical dressing, medical tape, athletic tape, or
surgical tape.
31. The medical article of claim 29 which is in the form of a
sensor, an electrode, or an ostomy appliance.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to pressure sensitive adhesive
compositions. In particular, the invention discloses fiber
reinforced pressure sensitive adhesives and methods for their
preparation and use.
BACKGROUND OF THE INVENTION
[0002] Pressure sensitive adhesives are generally characterized by
their properties. Pressure sensitive adhesives are well known to
one of ordinary skill in the art to possess properties including
the following: (1) aggressive and permanent tack, (2) adherence to
a substrate with no more than finger pressure, (3) sufficient
ability to hold onto an adherend, and (4) sufficient cohesive
strength to be removed cleanly from the adherend. Many pressure
sensitive adhesives must satisfy these properties under an array of
different stress rate conditions. Additives may be included in the
pressure sensitive adhesive to optimize the characteristics of the
pressure sensitive adhesive.
[0003] In particular systems, the additive improves the cohesive
strength of the pressure sensitive adhesives, yet the tack is
reduced. For example, a non-tacky additive may be mixed with a
pressure sensitive adhesive, reducing the tack of the mixture (as
compared to the tack of the pressure sensitive adhesive without the
additive). In a specific example, thermoplastic polymers have been
added to styrene block copolymer adhesives to reduce the tack of
the resulting pressure sensitive adhesives. However, to avoid loss
of tack when enhancing the pressure sensitive adhesive's cohesive
strength, care must be taken in choosing an additive.
[0004] U.S. Pat. No. 6,063,838 discloses a pressure sensitive
adhesive comprising a blend of at least two components, wherein the
first component is at least one pressure sensitive adhesive and the
second component is at least one thermoplastic material, wherein
the components form a blended composition having more than one
domain and, wherein one domain is substantially continuous
(generally, the pressure sensitive adhesive) and the other domain
is substantially fibrinous to schistose (generally, the
thermoplastic material). The blended pressure sensitive adhesives
of the U.S. Pat. No. 6,063,838 patent provide adhesives having one
or more of the following properties including: (1) a peel adhesion
greater than and shear strength similar to that of the pressure
sensitive adhesive component if used alone, (2) a shear strength
greater than and peel adhesion similar to that of the pressure
sensitive adhesive component if used alone, (3) an anisotropic peel
adhesion, (4) an anisotropic shear strength, (5) a tensile stress
in the down-web direction that is at least two times greater than
the tensile stress in the cross-web direction for all elongations
up to the break elongation, and (6) a resistance to impact shear
that is at least two times greater than that of the pressure
sensitive adhesive component if used alone.
[0005] What is desired is an adhesive composition that has improved
cohesive strength without losing the tackiness indicative of a
pressure sensitive adhesive. In coN.J.unction, it is desirable to
create an adhesive composition that is removable from a substrate
with ease without losing the tackiness indicative of a pressure
sensitive adhesive. Additionally, a stretch removable adhesive
composition is desirable.
SUMMARY OF THE INVENTION
[0006] This invention is directed to a fiber reinforced adhesive
composition comprising a pressure sensitive adhesive matrix and a
fibrous reinforcing material within the pressure sensitive adhesive
matrix. The fiber reinforced adhesive composition of the invention
allows for an improved cohesive strength over the pressure
sensitive adhesive alone, yet the tack of the pressure sensitive
adhesive remains substantially unreduced.
[0007] The adhesive composition has a yield strength and a tensile
strength. In one embodiment, the tensile strength is about 0.7 MPa
or greater. In another embodiment, the tensile strength is at least
about 150% of the yield strength when tested according to ASTM D
882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute). In one embodiment, the adhesive composition
exhibits at least 50% elongation when measured according to ASTM D
882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute). In certain embodiments, the fibrous
reinforcing material comprises substantially continuous fibers
within the pressure sensitive adhesive matrix. Additionally, in
preferred embodiments, the fiber reinforced adhesive composition
will display stretch removable characteristics and easy removal
from a substrate.
[0008] In addition, the invention is directed to a method for
making a fiber reinforced adhesive. The method comprises forming a
mixture comprising a pressure sensitive adhesive with a reinforcing
material capable of forming fibers when subjected to an elongating
shear force, and subjecting the mixture to the elongating shear
force.
[0009] In this application, the following terms are defined as
follows, unless otherwise stated:
[0010] "Stretch removable" means that a pressure sensitive
adhesive, when pulled and elongated (preferably from a substrate
surface at a rate of 30 centimeters/minute and at an angle of no
greater than 45.degree.), detaches from a substrate surface without
significant damage to the substrate surface (e.g. tearing), and
without leaving a significant residue, preferably that which is
visible to the unaided human eye on the substrate.
[0011] "Substantially continuous" means that for an at least 0.5
centimeter length sample of the adhesive composition taken in the
machine direction, at least 50% of the fibers present in the sample
are continuous (i.e. unbroken).
[0012] "Tensile strength" is the maximum tensile strength at break
when tested according to ASTM D 882-97 at a crosshead speed of 12
inches/minute (30 centimeters/minute).
DETAILED DESCRIPTION OF THE INVENTION
[0013] The present invention is directed to a fiber reinforced
adhesive composition comprising a pressure sensitive adhesive
matrix and a reinforcing material within the pressure sensitive
adhesive matrix. The fiber reinforced adhesive composition of the
present invention has improved cohesive strength, as represented by
a higher tensile strength of the fiber reinforced adhesive
composition as compared to the pressure sensitive adhesive without
the reinforcing material. Additionally, in a preferred embodiment,
the adhesive composition is stretch removable. The adhesive
composition of the invention has these properties while maintaining
substantially unreduced tack properties in many embodiments.
[0014] In the present invention, the adhesive composition has a
yield strength. In certain embodiments, the yield strength is no
less than about 0.1 MPa when measured according to ASTM D 882-97 at
a crosshead speed of 12 inches/minute (30 centimeters/minute). In
specific embodiments, the yield strength is no less than about 0.2
MPa when measured according to ASTM D 882-97 at a crosshead speed
of 12 inches/minute (30 centimeters/minute).
[0015] Additionally, the adhesive composition has a tensile
strength of at least about 150% of the yield strength when measured
according to ASTM D 882-97 at a crosshead speed of 12 inches/minute
(30 centimeters/minute). In certain embodiments, the tensile
strength is about 0.7 MPa or greater when measured according to
ASTM D 882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute). In specific embodiments, the tensile strength
is about 0.8 MPa or greater when measured according to ASTM D
882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute). The adhesive composition may have a tensile
strength of at least about two times greater than the tensile
strength of the pressure sensitive adhesive alone when measured
according to ASTM D 882-97 at a crosshead speed of 12 inches/minute
(30 centimeters/minute).
[0016] For preferred embodiments, the elongation at break for the
adhesive composition is at least about 50% when measured according
to ASTM D 882-97 at a crosshead speed of 12 inches/minute (30
centimeters/minute), preferably more than about 200%, and may be
higher than about 300%. In some embodiments the elongation at break
is in excess of about 800%.
[0017] Additionally, in preferred embodiments, the amount of force
required to remove the adhesive composition from a polypropylene
substrate at an angle of between 15.degree. and 35.degree. is less
than about 20 Newtons/decimeter. This low removal force permits
facile removal of the adhesive composition from a substrate. In
certain embodiments, the force necessary to remove the adhesive
composition from a substrate at such an angle is as low as about 7
Newtons/decimeter.
[0018] Pressure Sensitive Adhesive
[0019] Any suitable pressure sensitive adhesive composition can be
used for this invention. The pressure sensitive adhesive component
can be any material that has pressure sensitive adhesive
properties. Furthermore, the pressure sensitive adhesive component
can be a single pressure sensitive adhesive or the pressure
sensitive adhesive can be a combination of two or more pressure
sensitive adhesives.
[0020] Pressure sensitive adhesives useful in the present invention
include, for example, those based on natural rubbers, synthetic
rubbers, styrene block copolymers, polyvinyl ethers, poly
(meth)acrylates (including both acrylates and methacrylates),
polyolefins, and silicones.
[0021] The pressure sensitive adhesive may be inherently tacky. If
desired, tackifiers may be added to a base material to form the
pressure sensitive adhesive. Useful tackifiers include, for
example, rosin ester resins, aromatic hydrocarbon resins, aliphatic
hydrocarbon resins, and terpene resins. Other materials can be
added for special purposes, including, for example, oils,
plasticizers, antioxidants, ultraviolet ("UV") stabilizers,
hydrogenated butyl rubber, pigments, and curing agents.
[0022] In a preferred embodiment, the pressure sensitive adhesive
is based on at least one poly(meth)acrylate (e.g. is a
(meth)acrylic pressure sensitive adhesive). Poly(meth)acrylic
pressure sensitive adhesives are derived from, for example, at
least one alkyl (meth)acrylate ester monomer such as, for example,
isooctyl acrylate, isononyl acrylate, 2-methyl-butyl acrylate,
2-ethyl-hexyl acrylate and n-butyl acrylate; and at least one
optional co-monomer component such as, for example, (meth)acrylic
acid, vinyl acetate, N-vinyl pyrrolidone, (meth)acrylamide, a vinyl
ester, a fumarate, a styrene macromer, or combinations thereof.
Preferably, the poly(meth)acrylic pressure sensitive adhesive is
derived from between about 0 and about 20 weight percent of acrylic
acid and between about 100 and about 80 weight percent of at least
one of isooctyl acrylate, 2-ethyl-hexyl acrylate or n-butyl
acrylate composition, preferably isooctyl acrylate. A preferred
embodiment for the present invention is derived from between about
2 and about 10 weight percent acrylic acid and between about 90 and
about 98 weight percent of at least one of isooctyl acrylate,
2-ethyl-hexyl acrylate or n-butyl acrylate composition. One
specific embodiment for the present invention is derived from about
2 weight percent to about 10 weight percent acrylic acid, about 90
weight percent to about 98 weight percent of isooctyl acrylate, and
about 2 weight percent to about 6 weight percent styrene
macromer.
[0023] Reinforcing Material
[0024] Various reinforcing materials may be used to practice the
present invention. In preferred embodiments, the reinforcing
material is a polymer. In specific embodiments, the reinforcing
material is elastomeric. Preferably, the reinforcing material is a
semi-crystalline polymer. A semi-crystalline polymer is one having
both amorphous and crystalline domains. Many specific embodiments
incorporate semi-crystalline polymers, such as polycaprolactone
(PCL), polybutene (PB), copolymers derived from ethylene and at
least one other alpha-olefin monomer (e.g.
poly(ethylene-co-1-alkene) and
poly(ethylene-co-1-alkene-co-1-alkene)), ultra low density
polyethylene (e.g. having a density below 0.915 grams/cubic
centimeter, such as ATTANE 4202 commercially available from Dow
Chemical Co.), linear low density polyethylene (e.g. having a
density between 0.915 and 0.94 grams/cubic centimeter, such as
LL-3003, ECD-125, 377D60, 369G09, 363C32, 361C33, 357C32, 350D65,
350D64, 350D60, LL-3013, and LL-3001 commercially available from
ExxonMobil Corp.) or combinations thereof.
[0025] Preferred reinforcing materials have a measurable yield
strength. In certain embodiments, the yield strength of the
reinforcing material is less than about 20 MPa. The tensile
strength of the reinforcing material is preferably at least about
150% of its yield strength. In specific embodiments, the tensile
strength of the reinforcing material is higher than the tensile
strength of the pressure sensitive adhesive. These values are
measured using ASTM D 882-97 at a crosshead speed of 12
inches/minute (30 centimeters/minute).
[0026] The reinforcing material preferably has a melting point
above the use temperature of the adhesive composition. Similarly,
the reinforcing material preferably has a melting point above the
storage temperature of the adhesive composition or any article
manufactured with the adhesive composition. Both the use
temperature and the storage temperature should not exceed the
temperature that the pressure sensitive adhesive decomposes. In
certain embodiments, the reinforcing material has a melting point
of at least 70.degree. C. All temperatures are related as being
measurable by differential scanning calorimetry ("DSC") at a
scanning rate of 10.degree. C./minute.
[0027] It is particularly desirable for the reinforcing material to
have a melt viscosity similar to the melt viscosity of the pressure
sensitive adhesive at the processing temperature of the method of
this invention. In specific embodiments, the ratio of the
reinforcing material melt viscosity to the pressure sensitive
adhesive melt viscosity at the processing temperature is less than
about 3, preferably less than about 1.5. In particularly preferred
embodiments, the ratio is between about 0.5 and about 1.2 depending
on specific extrusion parameters (e.g. shear rate, screw speed,
temperature). Melt viscosity is measurable as understood by one
skilled in the art using a capillary viscometer.
[0028] The reinforcing material is preferably immiscible (i.e.
remains in a separate phase) in the pressure sensitive adhesive
during mixing so that the reinforcing material can be substantially
uniformly dispersed (i.e. distributed) in the pressure sensitive
adhesive. In specific embodiments, during mixing, the reinforcing
material is in the form of substantially spherical particles having
an average diameter less than about 20 micrometers. In certain
embodiments, the reinforcing material has an average diameter less
than about 10 micrometers.
[0029] In preferred embodiments, the reinforcing material exists as
substantially continuous fibers in the adhesive composition.
Specifically, according to one aspect of the invention, the fibers
are unbroken for at least about 0.5 centimeters in the machine
direction of the pressure sensitive adhesive matrix, preferably at
least about 2 centimeters. In more preferred embodiments, the
substantially continuous fibers are continuous for at least about 5
centimeters and most preferably at least about 8 centimeters.
According to another aspect of the invention, the substantially
continuous fibers generally have a maximum diameter of about 0.05
to about 5 micrometers, preferably from about 0.1 to about 1
micrometers. According to another aspect of the invention, the
aspect ratio (i.e. the ratio of the length to the diameter) of the
substantially continuous fibers is greater than about 1000.
[0030] Mixing
[0031] The reinforcing material is mixed with the pressure
sensitive adhesive before subjecting the mixture to an elongating
shear force. Mixing of the reinforcing material and the pressure
sensitive adhesive is done by any method that results in a
dispersion, preferably a substantially uniform dispersion, of the
reinforcing material in the pressure sensitive adhesive. For
example, melt blending, solvent blending, or any suitable physical
means are able to adequately mix the reinforcing material and the
pressure sensitive adhesive.
[0032] Melt blending devices include those that provide dispersive
mixing, distributive mixing, or a combination of dispersive and
distributive mixing. Both batch and continuous methods of melt
blending can be used. Examples of batch methods include those using
a BRABENDER (e.g. a BRABENDER PREP CENTER, commercially available
from C.W. Brabender Instruments, Inc.; South Hackensack, N.J.) or
BANBURY internal mixing and roll milling equipment (e.g. equipment
available from Farrel Co.; Ansonia, Conn.). After batch mixing, the
mixture created may be immediately quenched and stored below
melting temperature of the mixture for later processing.
[0033] Examples of continuous methods include single screw
extruding, twin screw extruding, disk extruding, reciprocating
single screw extruding, and pin barrel single screw extruding. The
continuous methods can include utilizing both distributive
elements, such as cavity transfer mixers (e.g. CTM, commercially
available from RAPRA Technology, Ltd.; Shrewsbury, England) and pin
mixing elements, static mixing elements or dispersive mixing
elements (commercially available from e.g., MADDOCK mixing elements
or SAXTON mixing elements as described in "Mixing in Single-Screw
Extruders," Mixing in Polymer Processing, edited by Chris
Rauwendaal (Marcel Dekker Inc.: New York (1991), pp. 129, 176-177,
and 185-186).
[0034] In certain embodiments, the reinforcing material comprises
between about 2 and about 70 weight percent of the adhesive
composition. In specific embodiments, the reinforcing material
comprises between about 5 and about 60 weight percent of the
adhesive composition. In preferred embodiments, the reinforcing
material comprises between about 5 and about 50 weight percent of
the adhesive composition. Typically, the pressure sensitive
adhesive component comprises between about 30 and about 98 weight
percent, preferably between about 40 and about 95 weight percent
and more preferably between about 50 and about 95 weight percent of
the total adhesive composition. Other additives may also be mixed
into the pressure sensitive adhesive composition prior to
application thereof, depending on the desired properties of the
applied adhesive.
[0035] Method of Forming the Fiber Reinforced Pressure Sensitive
Adhesive
[0036] The adhesive composition is subjected to an elongating shear
force, creating fibers from the reinforcing material in a pressure
sensitive adhesive matrix. Preferably, the adhesive composition is
formed by continuous forming methods, including hot melt coating,
drawing or extruding, the adhesive composition from the elongating
shear force device (e.g. a draw die, a film die, or a rotary rod
die) and subsequently contacting the drawn adhesive composition to
a moving web (e.g. plastic) or other suitable substrate. A related
continuous forming method involves extruding the adhesive
composition and a co-extruded backing material from a film die and
cooling the layered product to form an adhesive tape. Other
continuous forming methods involve directly contacting the adhesive
composition to a rapidly moving web or other suitable preformed
substrate. Using this method, the adhesive composition is applied
to the moving preformed web using a die having flexible die lips,
such as a rotary rod die.
[0037] After forming by any of these continuous methods, the
fibers, thus formed, can be solidified by lowering the temperature
of the adhesive composition to below the melting point of the
reinforcing material. For example, the temperature may be lowered
by quenching the adhesive composition using either direct methods
(e.g., chill rolls or water baths) or indirect methods (e.g., air
or gas impingement). The resulting fiber reinforced adhesive
composition is then cooled to ambient temperature.
[0038] Application of the Fiber Reinforced Adhesive Composition
[0039] The fiber reinforced adhesive composition can be used for a
variety of applications. For example, the fiber reinforced adhesive
composition can be applied to sheeting products (e.g., decorative,
reflective, and graphical), labelstock, and tape backings to form,
for example, first aid dressings, medical drapes, or medical tapes.
Additionally, the fiber reinforced adhesive composition of the
present invention can be used in optical fibers and tapes. The
substrate can be any suitable type of material depending on the
desired application.
[0040] To form a tape, the fiber reinforced adhesive composition is
coated onto at least a portion of a suitable backing. A release
material (e.g., low adhesion backsize) can be applied to the
opposite side of the backing, if desired. When double-coated tapes
are formed, the fiber reinforced adhesive composition is coated,
for example by co-extrusion or lamination, onto at least a portion
of both sides of the backing. Additionally, the adhesive can be
coated on at least one release liner to form a transfer tape.
[0041] Typically, the backing comprises a nonwoven, paper,
polypropylene (e.g., biaxially oriented polypropylene (BOPP)),
polyethylene, polyester (e.g., polyethylene terephthalate), or a
release liner (e.g., siliconized liner). In specific embodiments,
the backing is stretchable so that an article comprising the
adhesive composition and the backing would be stretch
removable.
[0042] In specific embodiments, the adhesive compositions of the
present invention are used in tapes that include gauze pads, for
example, and are used as first aid dressings (i.e., wound or
surgical dressings). They can also be used in a wide variety of
other medical articles, such as medical tapes, athletic tapes,
surgical drapes, or tapes or tabs used in adhering medical devices
such as sensors, electrodes (as disclosed in U.S. Pat. No.
5,215,087 and U.S. Pat. No. 6,171,985, for example), ostomy
appliances, or the like.
[0043] Preferably, webs made from natural or synthetic fibers or
mixtures thereof can be used to form backings, particularly for
medical articles. Woven or nonwoven materials can be employed for
webs, with nonwoven materials being preferred for most
applications. Melt-blown or spunbond techniques can be employed to
make such nonwoven webs. Nonwoven webs can also be prepared, for
example, on a RANDO WEBBER (Rando Corporation, Macedon, N.Y.)
air-laying machine or on a carding machine.
[0044] Typically, fibers forming a nonwoven tape backing are
intimately entangled with each other in the form of a coherent
breathable fibrous nonwoven tape backing. Suitable nonwoven tape
backings can be formed as melt blown microfiber webs using the
apparatus discussed, for example, in Wente, Van A., "Superfine
Thermoplastic Fibers," Industrial Engineering Chemistry, Vol. 48,
pages 1342-1346; Wente, Van A. et al., "Manufacture of Superfine
Organic Fibers," Report No. 4364 of the Naval Research
Laboratories, published May 25, 1954; and in U.S. Pat. Nos.
3,849,241, 3,825,379, and others. These microfine fibers are termed
melt blown fibers or blown microfibers (BMF) and are generally
substantially continuous and form a coherent web between the exit
die orifice and a collecting surface by entanglement of the
microfibers, due in part to the turbulent airstream in which the
fibers are entrained.
[0045] Other conventional melt spinning type processes, such as
spunbond processes, where fibers are collected in a web form
immediately upon formation, can also be used to form the nonwoven
tape backing. Generally, the fibers are 100 microns or less in
diameter when formed by melt spinning type processes, preferably 50
microns or less.
[0046] Multicomponent fibers, if formed by the melt blown process,
can be produced as described in U.S. Pat. No. 5,176,952 (Joseph et
al); U.S. Pat. No. 5,232,770 (Joseph); U.S. Pat. No. 5,238,733
(Joseph et al); U.S. Pat. No. 5,258,220 (Joseph); or U.S. Pat. No.
5,248,455 (Joseph et al). Multicomponent fibers can also be
produced by a spunbond process as disclosed in U.S. Pat. No.
5,695,868 (McCormach); U.S. Pat. No. 5,336,552 (Strack et al); U.S.
Pat. No. 5,545,464 (Stokes); U.S. Pat. Nos. 5,382,400; 5,512,358
(Shawyer et al); or U.S. Pat. No. 5,498,463 (McDowall et al).
[0047] Representative examples of materials suitable for the
backing of the adhesive article of this invention include
polyolefins, such as polyethylene, including high density
polyethylene, low density polyethylene, linear low density
polyethylene, and linear ultra low density polyethylene,
polypropylene, and polybutylenes; vinyl copolymers, such as
polyvinyl chlorides, both plasticized and unplasticized, and
polyvinyl acetates; olefinic copolymers, such as
ethylene/methacrylate copolymers, ethylene/vinyl acetate
copolymers, acrylonitrile-butadiene-st- yrene copolymers, and
ethylene/propylene copolymers; acrylic polymers and copolymers;
polycaprolactones; and combinations of the foregoing. Mixtures or
blends of any plastic or plastic and elastomeric materials such as
polypropylene/polyethylene, polyurethane/polyolefin,
polyurethane/polycarbonate, polyurethane/polyester, can also be
used. Additionally, any nonstretchable material can be used for the
tearable backings or for those with perforations, including paper
and even metal. Preferred materials for the backing include
polyurethane, polypropylene, ethylene vinyl acetate, or
combinations thereof (e.g., blends, mixtures, etc.) in the form of
melt blown fibers. Preferred materials for film backings include
polycaprolactones and copolymers of ethylene/vinyl acetate and
linear low density polyethylene.
[0048] In a preferred embodiment, the backing is formed from
coherent multicomponent fibers having at least one pressure
sensitive adhesive region or layer and at least one non-pressure
sensitive adhesive region or layer as described in U.S. Pat. No.
6,107,219. In another preferred embodiment, the backing is a melt
blown polypropylene web available from Kimberly Clark Corp.;
Irving, Tex.
[0049] If the backing is in the form of a laminate, additional
components could be used, such as absorbent layers (e.g., gauze
pads) for adhesive bandage products, or the like. If absorbent
layers are used, they are typically thin, coherent, conformable,
and able to flex and not interfere with the stretch removable
characteristics of the articles, although they can be stretchable
or not.
[0050] If a laminate, there may be one or more additional layers.
Preferably, the outermost layer of such a laminate is a film that
is substantially impervious to fluids, such as could arise from the
external environment, yet permits passage of moisture vapor such
that the adhesive article is breathable (typically, having a
moisture vapor transmission rate (MVTR) of at least about 500
g/m.sup.2/day). Typically this breathable, liquid impervious film
is the outermost (i.e., top) layer. Examples of such film materials
include polyurethanes, polyolefins, metallocene catalyzed
polyolefins, polyesters, polyamides, polyetheresters, and A-B-A
block copolymers, such as KRATON copolymers available from Shell
Chemical Ltd.; Houston, Tex.
EXAMPLES
[0051] This invention is further illustrated by the following
examples that are not intended to limit the scope of the invention.
These examples are merely for illustrative purposes only and are
not meant to be limiting on the scope of the appended claims. All
parts, percentages, ratios, etc. in the examples and the rest of
the specification are by weight unless indicated otherwise. All
ultraviolet curing of adhesives described in the examples occurred
with the adhesive exposed to the ultraviolet radiation source.
1 Table of Abbreviations Abbreviation/ Trade Designation
Description AA Acrylic acid ATTANE 4202 Ultra Low Density Linear
Poly(ethylene-co-octene) derived from 10% octene, commercially
available from Dow Chemical Co.; Midland, MI. CV-60 A controlled
viscosity grade natural rubber, available from The Goodyear Tire
and Rubber Co.; Akron, OH. ELVAX 210 Ethylene-vinyl acetate
copolymer commercially available from E.I. duPont deNemours and
Co.; Wilmington, DE. ELVAX 240 Ethylene-vinyl acetate copolymer
commercially available from E.I. duPont deNemours and Co.;
Wilmington, DE. ELVAX 450 Ethylene-vinyl acetate copolymer
commercially available from E.I. duPont deNemours and Co.;
Wilmington, DE. ELVAX 660 Ethylene-vinyl acetate copolymer
commercially available from E.I. duPont deNemours and Co.;
Wilmington, DE. ENGAGE 8200 Ethylene-octene copolymer derived from
24% octene, having a DSC measured melting peak temperature of
60.degree. C., commercially available from DuPont Dow Elastomers
LLC; Wilmington, DE. ENGAGE 8490 Ethylene-octene copolymer derived
from 14% octene, commercially available from DuPont Dow Elastomers
LLC; Wilmington, DE. ESCOREZ 2393 Aliphatic/aromatic mixed
tackifier resin commercially available from ExxonMobil Corp.;
Houston, TX. HDPE High Density Polyethylene, having a weight
average molecular weight of 125,000 and a density of 0.95
grams/cubic centimeter, commercially available from Scientific
Polymer Products, Inc.; Ontario, NY. IOA Isooctyl acrylate KRATON
D1107 Styrene-isoprene-styrene block copolymer commercially
available from Shell Chemicals Ltd.; Houston, TX. LDPE Low density
polyethylene, having a density of 0.918 grams/cubic centimeter,
commercially available from Aldrich Chemical Co.; Milwaukee, WI.
MAA Methacrylic acid PB Isotactic Polybutene, having a weight
average molecular weight of 185,000, commercially available from
Aldrich Chemical Co.; Milwaukee, WI. PCL Polycaprolactone, having a
weight average molecular weight of 80,000, commercially available
from Aldrich Chemical Co.; Milwaukee, WI. PEBH Metallocene
catalyzed poly(ethylene-co-1-buten- e-co-1-hexene), with a melt
index of 3.5, commercially available from Aldrich Chemical Co.;
Milwaukee, WI. PET An aminated-polybutadiene primed polyester film
of polyethylene terephthalate having a thickness of 38 micrometers.
PMMA Polymethylmethacrylate, having a weight average molecular
weight of 350,000 commercially available from Aldrich Chemical Co.;
Milwaukee, WI. PP substrate Polypropylene substrate commercially
available from Aeromat Plastics Inc.; Bumsville, MN. PS
Polystyrene, having a weight average molecular weight of 280,000,
commercially available from Aldrich Chemical Co.; Milwaukee, WI.
PSA-1 IOA/AA copolymer pressure sensitive adhesive, derived from an
approximate ratio of IOA/AA monomers of 90/10. The pressure
sensitive adhesive was prepared by mixing 21.6 grams of IQA, 2.4
grams of AA, 0.28 gram of carbon tetrabromide chain transfer agent,
and 36 grams of ethyl acetate in a glass vessel. To this mixture,
0.072 gram of VAZO 64 was added. The vessel was made inert with
nitrogen gas and sealed. The sealed bottle was tumbled in a
55.degree. C. water bath for 24 hours. The resultant polymer was
coated onto a siliconized polyester release liner and oven dried
for 15 minutes at 65.degree. C. to recover the dried polymer. PSA-2
Pressure sensitive adhesive containing a mixture of 50 parts of
KRATON D1107 and 50 parts of WINGTACK PLUS. PSA-3 Kraton pressure
sensitive adhesive HL-2552X, commercially available from H.B.
Fuller Co.; St. Paul, MN. PSA-4 IOA/MAA copolymer pressure
sensitive adhesive derived from an approximate ratio of IOA/MAA
monomers of 96/4. The pressure sensitive adhesive was prepared as
described in U.S. Pat. No. 4,952,650, Example 5, and dried prior to
use. PSA-5 IOA/AA copolymer pressure sensitive adhesive, derived
from an approximate ratio of IOA/AA monomers of 90/10. The pressure
sensitive adhesive was polymerized as described in U.S. Pat. No.
5,804,610, Example 1, with the exception that the pouch was removed
prior to feeding the pressure sensitive adhesive into the extruder.
PSA-6 IOA/AA copolymer pressure sensitive adhesive grafted with a
polystyrene macromer, derived from an approximate ratio of
IOA/AA/polystyrene components of 92/4/4. The pressure sensitive
adhesive was prepared as described in U.S. Pat. No. 4,554,324,
Example 74, except that the macromer was polystyrene and the
inherent viscosity of the resulting PSA-6 was 0.65 dl/g (measured
in ethylacetate at 27.degree. C.) PSA-7 PSA-6 mixed with 23%
ESCOREZ 2393 tackifier. PSA-8 IOA/AA copolymer pressure sensitive
adhesive, derived from an approximate ratio of IOA/AA monomers of
95.5/4.5 and polymerized as described in U.S. Pat. No. RE 24,906,
Example 5, and dried prior to use. PSA-9 Natural rubber pressure
sensitive adhesive prepared from CV-60 as described in U.S. Pat.
No. 6,063,838, Examples 43-44. REGALREZ 1126 Hydrogenated tackifier
resin commercially available from Hercules, Inc.; Wilmington, DE.
WINGTACK PLUS A C5 hydrocarbon tackifier resin commercially
available from Goodyear Tire & Rubber Company; Akron, OH.
[0052] Test Methods
[0053] Tensile Testing
[0054] Tensile testing was carried out according to ASTM test
method D 882-97 "Standard Test Method for Tensile Properties of
Thin Plastic Sheeting" using an INSTRON materials tester
(commercially available from Instron; Canton, Mass.) at a crosshead
speed of 30 centimeters/minute (12 inches/minute). Using this test,
the values for "Yield Strength", "Tensile Strength", and "Percent
Elongation at Break" were obtained.
[0055] 180.degree. Peel Adhesion
[0056] This peel adhesion test is similar to the test method
described in ASTM D 3330-90, substituting a glass, high density
polyethylene or polypropylene substrate for the stainless steel
substrate described in the test. The substrate used is noted in
each particular example.
[0057] Adhesive-coated strips that had equilibrated at constant
temperature (21.degree. C.) and humidity (50% relative humidity)
for at least 24 hours, were adhered to a substrate panel. The
substrate panel was either solvent-washed glass, polypropylene
(PP), or high density polyethylene (HDPE) using a 2 kilogram roller
passed once over the strip. The bonded assembly was allowed to
dwell at room temperature for one minute. The assembly was then
tested for 180.degree. peel adhesion in the machine direction using
an IMASS slip/peel tester (Model 3M90, commercially available from
Instrumentors Inc., Strongsville, OH) at a crosshead speed of 30
centimeters/minute (12 inches/minute).
[0058] Stretch Release Test Method
[0059] Adhesive-coated strips, which had equilibrated at constant
temperature (21.degree. C.) and humidity (50% relative humidity)
for at least 24 hours, were adhered to a polypropylene (PP)
substrate panel using a 2 kilogram roller passed once over the
strip. The bonded assembly was allowed to dwell at room temperature
for one minute. The assembly was then tested for stretch release by
pulling at an angle of between 15 and 35.degree. either "by hand",
or "mechanically" using an IMASS slip/peel tester (Model 3M90,
commercially available from Instrumentors Inc., Strongsville, OH)
at a crosshead speed of 30 centimeters/minute (12 inches/minute).
The data are reported for the by hand samples as "broke" if the
sample broke before detachment (i.e. the sample did not stretch
release), or "yes" if the sample exhibited stretch release
properties. For the mechanically tested samples, the data is
reported as "broke" if the sample broke (i.e. the sample did not
stretch release), or, if the sample did exhibit stretch release
properties, the maximum stretch release force in Newtons/decimeter
is reported.
[0060] Probe Tack Test
[0061] Probe tack measurements were made following the test method
described in ASTM D 2979-95 using a TA-XY2 texture tester
(commercially available from Stable Microsystems, Surrey,
U.K.).
[0062] Solvent Extraction Test
[0063] To determine the continuity of the fibrous reinforcing
material of the adhesive composition, the pressure sensitive
adhesive matrix was dissolved, leaving behind the fibrous
reinforcing material. A strip of the adhesive composition film
(approximately 7.5 centimeters long by 2.5 centimeters wide) was
cut from the film in the machine direction. The strip was suspended
on an open frame by looping the film over the edge of the open
frame. The frame and adhesive strip were immersed in a solvent
capable of dissolving the pressure sensitive adhesive but not the
fibrous reinforcing material. After 24 hours the sample was checked
to determine if the pressure sensitive adhesive had completely
dissolved and if the fibrous reinforcing material remained on the
frame. If fibers were not continuous for at least 5 centimeters,
nothing remained on the frame. The samples were rated as "pass" if
fibers remained on the frame and "fail" if no fibers remained on
the frame.
[0064] Tensile Properties of Reinforcing Material
[0065] Films of possible fibrous reinforcing material were prepared
by hot-press molding each reinforcing material to a thickness of
102 micrometers. The films were tested using the Tensile Testing
method described above. The results are shown in Table 1.
Additionally, the materials are characterized as being elastomeric
(rebounds upon deformation) or plastic (deforms permanently).
2TABLE 1 Yield Tensile Percent Strength Strength Elongation at
Plastic or Polymer (MPa) (MPa) Break (%) Elastomeric PEBH 5.09
31.72 730 Elastomeric PCL 7.45 16.41 620 Elastomeric ATTANE 4202
8.27 27.58 >800 Elastomeric HDPE 20.55 14.34 370 Plastic PMMA
25.51 25.51 <10 Plastic
Comparative Example C1
[0066] A sample of PSA-1 was hot melt coated between two release
liners at 150.degree. C. using a HAAKE single screw extruder
(commercially available from Haake, Inc.; Paramus, N.J.) equipped
with a draw die. The resulting film had a thickness of 127
micrometers. The tensile properties of the film were determined as
described in the Tensile Testing method above. The results are
shown in Table 2. A portion of the film was laminated to a PET
backing to make a tape. The resulting tape was passed below a
Fusion H-bulb lamp (commercially available from Fusion Total
Ultraviolet Systems, Inc.; Gaithersburg, Md.) at a crosshead speed
of 15 meters/minute for a total ultraviolet dose of 300
milliJoules/cm.sup.2. The tape was tested for 1800 Peel Adhesion
from glass. The results are shown in Table 3.
COMPARATIVE EXAMPLE C2
[0067] A mixture of 90 parts PSA-1, 10 parts ENGAGE 8200 and 0.2
part benzophenone was prepared in a BRABENDER mixer (commercially
available from C.W. Brabender Instruments, South Hackensack, N.J.)
at 140.degree. C. to 150.degree. C. for 8 to 10 minutes. The
resulting mixture was hot melt coated between two release liners at
150.degree. C. using a HAAKE single screw extruder (commercially
available from Haake, Inc.; Paramus, N.J.) equipped with a draw
die. The resulting film had a thickness of 127 micrometers. The
tensile properties of the film were determined as described in the
Tensile Testing method above. The results are shown in Table 2. A
portion of the film was laminated to a PET backing to make a tape.
The resulting tape was passed below a Fusion H-bulb lamp
(commercially available from Fusion Total Ultraviolet Systems,
Inc.; Gaithersburg, Md.) at a crosshead speed of 15 meters/minute
for a total ultraviolet dose of 300 milliJoules/cm.sup.2. The tape
was tested for 180.degree. Peel Adhesion from glass. The results
are shown in Table 3.
COMPARATIVE EXAMPLE C3
[0068] A mixture of 90 parts PSA-1, 10 parts of LDPE and 0.2 part
benzophenone were mixed in a BRABENDER mixer (commercially
available from C.W. Brabender Instruments, South Hackensack, N.J.)
at 140.degree. C. to 150.degree. C. for 8 to 10 minutes. The
resulting mixture was hot melt coated between two release liners at
150.degree. C. using a HAAKE single screw extruder (commercially
available from Haake, Inc.; Paramus, N.J.) equipped with a draw
die. The resulting film had a thickness of 127 micrometers. The
tensile properties of the film were determined as described in the
Tensile Testing method above. The results are shown in Table 2. A
portion of the film was laminated to a PET backing to make a tape.
The resulting tape was passed below a Fusion H-bulb lamp
(commercially available from Fusion Total Ultraviolet Systems,
Inc.; Gaithersburg, Md.) at a crosshead speed of 15 meters/minute
for a total ultraviolet dose of 300 milliJoules/cm2. The tape was
tested for 180.degree. Peel Adhesion from glass. The results are
shown in Table 3.
Example 1
[0069] A mixture of 90 parts PSA-1, 10 parts ENGAGE 8490 and 0.2
part benzophenone were mixed in a BRABENDER mixer (commercially
available from C.W. Brabender Instruments, South Hackensack, N.J.)
at 140.degree. C. to 150C for 8 to 10 minutes. The resulting
mixture was hot melt coated between two release liners at
150.degree. C. using a HAAKE single screw extruder (commercially
available from Haake, Inc.; Paramus, N.J.) equipped with a draw
die. The resulting film had a thickness of 127 micrometers. The
tensile properties of the film were determined as described in the
Tensile Testing method above. The results are shown in Table 2. A
portion of the film was laminated to a PET backing to make a tape.
The resulting tape was passed below a Fusion H-bulb lamp
(commercially available from Fusion Total Ultraviolet Systems,
Inc.; Gaithersburg, Md.) at a crosshead speed of 15 meters/minute
for a UV dose of 300 milliJoules/cm.sup.2. The tape was tested for
180.degree. Peel Adhesion from glass. The results are shown in
Table 3.
Example 2
[0070] A mixture of 90 parts PSA-1, 10 parts of ATTANE 4202 and 0.2
part benzophenone were mixed in a BRABENDER mixer (commercially
available from C.W. Brabender Instruments, South Hackensack, N.J.)
at 140.degree. C. to 150.degree. C. for 8 to 10 minutes. The
resulting mixture was hot melt coated between two release liners at
150.degree. C. using a HAAKE single screw extruder (commercially
available from Haake, Inc.; Paramus, N.J.) equipped with a draw
die. The resulting film had a thickness of 127 micrometers. The
tensile properties of the film were determined as described in the
Tensile Test Method above. The results are shown in Table 2. A
portion of the film was laminated to a PET backing to make a tape.
The resulting tape was passed below a Fusion H-bulb lamp
(commercially available from Fusion Total Ultraviolet Systems,
Inc.; Gaithersburg, Md.) at a crosshead speed of 15 meters/minute
for a UV dose of 300 milliJoules/cm.sup.2. The tape was tested for
180.degree. Peel Adhesion from glass. The results are shown in
Table 3.
3TABLE 2 Percent Elongation Yield Strength Tensile Strength at
Break Example (MegaPascals) (MegaPascals) (%) C1 0.04 0.06 >800
C2 0.18 0.65 >800 C3 1.19 1.59 320 1 0.33 1.70 760 2 0.54 2.05
700
[0071]
4 TABLE 3 180.degree. Peel Example Adhesion (N/dm) C1 57.8 C2 52.1
C3 61 9 1 95.0 2 88.4
Comparative Example C4
[0072] A sample of PSA-1 was hot melt coated between two release
liners at 150.degree. C. using a HAAKE single screw extruder
(commercially available from Haake, Inc.; Paramus, N.J.) equipped
with a draw die. The resulting film had a thickness of 127
micrometers and was laminated to a PET backing to make a tape. The
resulting tape was passed below a Fusion H-bulb lamp (commercially
available from Fusion Total Ultraviolet Systems, Inc.;
Gaithersburg, Md.) at a crosshead speed of 15 meters/minute for a
UV dose of 300 milliJoules/cm.sup.2. The tape was tested for
180.degree. Peel Adhesion from glass in the machine and the
cross-web directions. The results are shown in Table 4.
Example 3
[0073] A mixture of 90 parts PSA-1 and 10 parts of ATTANE 4202 were
mixed in a BRABENDER mixer (commercially available from C.W.
Brabender Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The resulting film
had a thickness of 127 micrometers and was laminated to a PET
backing to make a tape. The resulting tape was passed below a
Fusion H-bulb lamp (commercially available from Fusion Total
Ultraviolet Systems, Inc.; Gaithersburg, Md.) at a crosshead speed
of 15 meters/minute for a UV dose of 300 milliJoules/cm.sup.2. The
tape was tested for 180.degree. Peel Adhesion from glass in the
machine and the cross-web directions. The results are shown in
Table 4.
5TABLE 4 180.degree. Peel Adhesion in 180.degree. Peel Adhesion in
Cross- Example Machine Direction (N/dm) web Direction (N/dm) C4
81.4 65.9 3 128.9 141.3
Comparative Example C5
[0074] A sample of PSA-1 was hot melt coated between two release
liners at 150.degree. C. using a HAAKE single screw extruder
(commercially available from Haake, Inc.; Paramus, N.J.) equipped
with a draw die. The resulting film had a thickness of 51
micrometers and was laminated to a PET backing to make a tape. The
resulting tape was passed below a Fusion H-bulb lamp (commercially
available from Fusion Total Ultraviolet Systems, Inc.;
Gaithersburg, Md.) at a crosshead speed of 15 meters/minute for a
UV dose of 300 milliJoules/cm.sup.2. The tape was tested for
180.degree. Peel Adhesion from glass in the machine and cross-web
directions. The results are shown in Table 5.
Comparative Example C6
[0075] A mixture of 90 parts PSA-1 and 10 parts of LDPE were mixed
in a BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The resulting film
had a thickness of 51 micrometers and was laminated to a PET
backing to make a tape. The tape was tested for 180.degree. Peel
Adhesion from glass in the machine and cross-web directions. The
results are shown in Table 5.
Example 4
[0076] A mixture of 90 parts PSA-1 and 10 parts of ATTANE 4202 were
mixed in a BRABENDER mixer (commercially available from C.W.
Brabender Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The resulting film
had a thickness of 51 micrometers and was laminated to a PET
backing to make a tape. The resulting tape was passed below a
Fusion H-bulb lamp (commercially available from Fusion Total
Ultraviolet Systems, Inc.; Gaithersburg, Md.) at a crosshead speed
of 15 meters/minute for a UV dose of 300 milliJoules/cm.sup.2. The
tape was tested for 180.degree. Peel Adhesion from glass in the
machine and cross-web directions. The results are shown in Table
5.
6TABLE 5 180.degree. Peel Adhesion in 180.degree. Peel Adhesion in
Cross- Example Machine Direction (N/dm) web Direction (N/dm) CS
54.9 51.4 C6 36.7 63.0 4 96.9 88.4
Comparative Example C7
[0077] A sample of PSA-2 was hot melt coated between two release
liners at 150.degree. C. using a HAAKE single screw extruder
(commercially available from Haake, Inc.; Paramus, N.J.) equipped
with a draw die. The resulting film had a thickness of 127
micrometers and was laminated to a PET backing to make a tape. The
tape was tested for 180.degree. Peel Adhesion on various
substrates. The results are shown in Table 6.
Example 5
[0078] A mixture of 90 parts PSA-2 and 10 parts of ATTANE 4202 were
mixed in a BRABENDER mixer (commercially available from C.W.
Brabender Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The resulting film
had a thickness of 127 micrometers and was laminated to a PET
backing to make a tape. The tape was tested for 180.degree. Peel
Adhesion on various substrates. The results are shown in Table
6.
7TABLE 6 180.degree. Peel 180.degree. Peel 180.degree. Peel
Adhesion from Adhesion for Adhesion Example glass (N/dm) HDPE (N/dm
from PP (N/dm) C7 181 79 156 5 238 91 231
Comparative Example C8
[0079] A sample of PSA-3 was used as obtained and hot melt coated
between two release liners at 150.degree. C. using a HAAKE single
screw extruder (commercially available from Haake, Inc.; Paramus,
N.J.) equipped with a draw die. The resulting film had a thickness
of 127 micrometers and was laminated to a PET backing to make a
tape. The tape was tested for 180.degree. Peel Adhesion on various
substrates. The results are shown in Table 7.
Example 6
[0080] A mixture of 90 parts PSA-3 and 10 parts of ATTANE 4202 were
mixed in a BRABENDER mixer (commercially available from C.W.
Brabender Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The resulting film
had a thickness of 127 micrometers and was laminated to a PET
backing to make a tape. The tape was tested for 180.degree. Peel
Adhesion on various substrates. The results are shown in Table
7.
8TABLE 7 180.degree. Peel 180.degree. Peel 180.degree. Peel
Adhesion from Adhesion from Adhesion from Example glass (N/dm) HDPE
(N/dm) PP (N/dm) C8 53 25 33 6 100 23 42
Comparative Example C9
[0081] A sample of PSA-4 was hot melt coated between two release
liners at 150.degree. C. using a HAAKE single screw extruder
(commercially available from Haake, Inc.; Paramus, N.J.) equipped
with a draw die. The tensile properties of the film were determined
as described in the Tensile Testing method above. The results are
shown in Table 8.
Comparative Example C10
[0082] A mixture of 85 parts PSA-4 and 15 parts of PS were mixed in
a BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The tensile
properties of the film were determined as described in the Tensile
Testing method above. The results are shown in Table 8.
Comparative Example C11
[0083] A mixture of 85 parts PSA-4 and 15 parts HDPE were mixed in
a BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The tensile
properties of the film were determined as described in the Tensile
Testing method above. The results are shown in Table 8.
Example 7
[0084] A mixture of 85 parts PSA-4 and 15 parts of ATTANE 4202 were
mixed in a BRABENDER mixer (commercially available from C.W.
Brabender Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The tensile
properties of the film were determined as described in the Tensile
Testing method above. The results are shown in Table 8.
Example 8
[0085] A mixture of 85 parts PSA-4 and 15 parts PEBH were mixed in
a BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The tensile
properties of the film were determined as described in the Tensile
Testing method above. The results are shown in Table 8.
9TABLE 8 Percent Elongation Yield Strength Tensile Strength at
Break Example (MegaPascals) (MegaPascals) (%) C9 0.03 0.14 >800
C10 1.79 1.79 <50 C11 1.72 2.07 180 7 1.21 3.38 >800 8 0.47
2.83 630
Examples 9-13
[0086] The mixtures for Examples 9-13 were prepared using PSA-5
with the level of ATTANE 4202 shown in Table 9, were mixed in a
BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die. The tensile
properties of the films were determined as described in the Tensile
Testing method above. The results are shown in Table 9.
10TABLE 9 Level of Tensile Percent at ATTANE 4202 Yield Strength
Strength Elongation Example (weight %) (MegaPascals) (MegaPascals)
Break (%) 9 5 0.21 0.90 610 10 10 0.52 1.79 670 11 15 0.95 3.59 610
12 30 2.21 7.31 650 13 40 3.45 13.51 580
Examples 14-16 and Comparative Examples C12-C.sub.14
[0087] The mixtures for Examples 14-16 and Comparative Examples
C12-C.sub.14 were prepared using PSA-4 with 15 weight % of a
polymer as shown in Table 10, and were mixed in a BRABENDER mixer
(commercially available form C.W. Brabender Instruments, South
Hackensack, N.J.) at 140.degree. C. to 150.degree. C. for 8 to 10
minutes. The resulting mixture was hot melt coated between two
release liners at 150.degree. C. using a HAAKE single screw
extruder (commercially available from Haake, Inc.; Paramus, N.J.)
equipped with a draw die to give a thickness of 51 micrometers. The
stretch release properties of the films were determined as
described in the Stretch Release Test Method above. The results are
shown in Table 10.
11 TABLE 10 Polymer Added Stretch Release "by Example (15 weight %)
hand" C12 PMMA Broke C13 PS Broke C14 HDPE Broke 14 ATTANE 4202 Yes
15 PEBH Yes 16 PB Yes
Comparative Example C15
[0088] Examples 17-22 and Comparative Example C.sub.15 were
prepared using PSA-4 with the level of ATTANE 4202 shown in Table
11, and were mixed in a BRABENDER mixer (commercially available
from C.W. Brabender Instruments, South Hackensack, N.J.) at
140.degree. C. to 150.degree. C. for 8 to 10 minutes. The resulting
mixture was hot melt coated between two release liners at
150.degree. C. using a HAAKE single screw extruder (commercially
available from Haake, Inc.; Paramus, N.J.) equipped with a draw die
to give a thickness of 51 micrometers. The stretch release
properties of the films were determined as described in the Stretch
Release Test Method above. The results are shown in Table 11.
12 TABLE 11 Level of ATTANE Stretch Release Example 4202 (weight %)
Force (N/dm) C15 0 Broke 17 5 7.4 18 10 10.7 19 15 13.1 20 20 14.1
21 30 19.6 22 40 22.1
Examples 23-25 and Comparative Example C16
[0089] The mixtures for Examples 23-25 and Comparative Example C16
were prepared using PSA-6 with the level of ATTANE 4202 shown in
Table 12 mixed in a BRABENDER mixer (commercially available from
C.W. Brabender Instruments, South Hackensack, N.J.) at 140.degree.
C. to 150C for 8 to 10 minutes. The resulting mixture was hot melt
coated between two release liners at 150.degree. C. using a HAAKE
single screw extruder (commercially available from Haake, Inc.;
Paramus, N.J.) equipped with a draw die to give a thickness of 51
micrometers. The stretch release properties of the films were
determined as described in the Stretch Release Test Method above.
The results are shown in Table 12.
13 TABLE 12 Level of Stretch Release ATTANE 4202 Force Example
(weight %) (N/dm) C16 0 Broke 23 5 9.0 24 10 10.3 25 20 14.3
Examples 26-27 and Comparative Example C17
[0090] The mixtures for Examples 26-27 and Comparative Example C17
were prepared using PSA-7 with the level of ATTANE 4202 shown in
Table 13 mixed in a BRABENDER mixer (commercially available from
C.W. Brabender Instruments, South Hackensack, N.J.) at 140.degree.
C. to 150.degree. C. for 8 to 10 minutes. The resulting mixture was
hot melt coated between two release liners at 150.degree. C. using
a HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die to give a thickness
of 127 micrometers. The stretch release properties of the films
were determined as described in the Stretch Release Test Method
above. The results are shown in Table 13.
14 TABLE 13 Level of Stretch Release ATTANE 4202 Force Example
(weight %) (N/dm) C17 0 Broke 26 10 9.0 27 20 19.8
Examples 28-30 and Comparative Example C18
[0091] The mixtures for Examples 28-30 and Comparative Example C18
were prepared using PSA-6 with the level of ATTANE 4202 shown in
Table 14 mixed in a BRABENDER mixer (commercially available from
C.W. Brabender Instruments, South Hackensack, N.J.) at 140.degree.
C. to 150.degree. C. for 8 to 10 minutes. The resulting mixture was
hot melt coated between two release liners at 150.degree. C. using
a HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die to give a thickness
of 51 micrometers. The probe tack properties of the films were
determined as described in the Probe Tack Test method above. The
results are shown in Table 14.
15 TABLE 14 Probe Tack for 51 Level of micrometer thick ATTANE 4202
sample Example (weight %) (grams) C18 0 261 28 5 262 29 10 229 30
20 279
Examples 31-32 and Comparative Example C19
[0092] The mixtures for Examples 31-32 and Comparative Example C19
were prepared using PSA-7 with the level of ATTANE 4202 shown in
Table 15 mixed in a BRABENDER mixer (commercially available from
C.W. Brabender Instruments, South Hackensack, N.J.) at 140.degree.
C. to 150.degree. C. for 8 to 10 minutes. The resulting mixture was
hot melt coated between two release liners at 150.degree. C. using
a HAAKE single screw extruder (commercially available from Haake,
Inc.; Paramus, N.J.) equipped with a draw die to give a thickness
of 51 or 127 micrometers. The probe tack properties of the films
were determined as described in the Probe Tack Test method above.
The results are shown in Table 15.
16TABLE 15 Probe Tack for Probe Tack for 51 Level of 127 micrometer
micrometer thick ATTANE 4202 thick sample sample Example (weight %)
(grams) (grams) C19 0 442 376 31 10 340 328 32 20 384 316
Examples 33-37 and Comparative Example C20
[0093] The mixtures for Examples 33-37 and Comparative Example C20
were prepared using PSA-4 with the level of ATTANE 4202 shown in
Table 16 mixed in a BRABENDER mixer (commercially available from
C.W. Brabender Instruments, South Hackensack, N.J.) at 140.degree.
C. to 150.degree. C. for 8 to 10 minutes. The resulting mixtures
were hot melt coated between two release liners at 150.degree. C.
using a HAAKE single screw extruder (commercially available from
Haake, Inc.; Paramus, N.J.) equipped with a draw die to give films
having a thickness of 51 or 127 micrometers. The probe tack
properties of the films were determined as described in the Probe
Tack Test method above. The results are shown in Table 16.
17TABLE 16 Probe Tack for Probe Tack for 51 Level of 127 micrometer
micrometer thick ATTANE 4202 thick sample sample Example (weight %)
(grams) (grams) C20 0 249 160 33 5 261 197 34 10 276 119 35 15 157
156 36 20 113 103 37 30 87 73
Examples C21-C.sub.22
[0094] Mixtures of PSA-8 and ELVAX 240 were prepared with the
levels of ELVAX 240 shown in Table 17 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 17.
18TABLE 17 Percent Level of Elongation ELVAX 240 Yield Strength
Tensile Strength at Break Example (weight %) (MegaPascals)
(MegaPascals) (%) C21 10 1.01 1.10 408 C22 15 1.43 1.52 460
Comparative Examples C23-C.sub.24
[0095] Mixtures of PSA-8 and ELVAX 210 were prepared with the
levels of ELVAX 210 shown in Table 18 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 18.
19TABLE 18 Percent Level of Elongation ELVAX 210 Yield Strength
Tensile Strength at Break Example (weight %) (MegaPascals)
(MegaPascals) (%) C23 10 1.38 1.42 470 C24 15 1.45 1.52 460
Comparative Examples C25-C.sub.26
[0096] Mixtures of PSA-9 and ELVAX 240 were prepared with the
levels of ELVAX 240 shown in Table 19 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 43-44. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 19.
20TABLE 19 Percent Level of Elongation ELVAX 240 Yield Strength
Tensile Strength at Break Example (weight %) (MegaPascals)
(MegaPascals) (%) C25 10 0.33 0.37 270 C26 15 0.32 0.36 120
Comparative Examples C27-C.sub.28
[0097] Mixtures of PSA-9 and ELVAX 210 were prepared with the
levels of ELVAX 210 shown in Table 20 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 43-44. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 20.
21TABLE 20 Percent Level of Elongation at Exam- ELVAX 210 Yield
Strength Tensile Strength Break ple (weight %) (MegaPascals)
(MegaPascals) (%) C27 10 0.07 0.08 160 C28 15 0.14 0.16 220
Comparative Examples C29-C.sub.30
[0098] Mixtures of PSA-8 and ELVAX 450 were prepared with the
levels of ELVAX 450 shown in Table 21 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 21.
22TABLE 21 Percent Level of Elongation at Exam- ELVAX 450 Yield
Strength Tensile Strength Break ple (weight %) (MegaPascals)
(MegaPascals) (%) C29 10 1.65 1.72 260 C30 15 2.55 2.69 270
Comparative Examples C31-C.sub.32
[0099] Mixtures of PSA-8 and ELVAX 660 were prepared with the
levels of ELVAX 660 shown in Table 22 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The tensile properties of the films were determined
as described in the Tensile Testing method above. The results are
shown in Table 22.
23TABLE 22 Percent Level of Elongation at Exam- ELVAX 660 Yield
Strength Tensile Strength Break ple (weight %) (MegaPascals)
(MegaPascals) (%) C31 10 2.41 2.48 220 C32 15 2.14 2.21 240
Examples 38-41
[0100] The mixtures for Examples 38-41 were prepared using PSA-5
with the level of ATTANE 4202 shown in Table 23, and were mixed in
a BRABENDER mixer (commercially available from C.W. Brabender
Instruments, South Hackensack, N.J.) at 140.degree. C. to
150.degree. C. for 8 to 10 minutes. The resulting mixture was hot
melt coated between two release liners at 150.degree. C. using a
HAAKE single screw extruder (commercially available from Haake,
Inc., Paramus, N.J.) equipped with a draw die. The solvent
extraction properties of the film were determined as described in
the Solvent Extraction Test method above. The results are shown in
Table 23.
24TABLE 23 Level of ATTANE 4202 Solvent Extraction Example (weight
%) Test Result 38 10 Pass 39 15 Pass 40 30 Pass 41 40 Pass
Comparative Examples C33-C34
[0101] Mixtures of PSA-8, with ELVAX 210 were prepared with the
levels of ELVAX 210 shown in the Table 24 and hot melt coated to
form films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 24.
25TABLE 24 Level of ELVAX 210 Solvent Extraction Example (weight %)
Test Result C33 10 Fail C34 15 Fail
Comparative Examples C35-C.sub.36
[0102] Mixtures of PSA-8 and ELVAX 240 were prepared with the
levels of ELVAX 240 shown in Table 25 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 25.
26TABLE 25 Level of ELVAX 240 Solvent Extraction Example (weight %)
Test Result C35 10 Fail C36 15 Fail
Comparative Examples C37-C.sub.38
[0103] Mixtures of PSA-9 and ELVAX 210 were prepared with the
levels of ELVAX 210 shown in Table 26 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 43-44. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 26.
27TABLE 26 Level of ELVAX 210 Solvent Extraction Example (weight %)
Test Result C37 10 Fail C38 15 Fail
Comparative Examples C39-C.sub.40
[0104] Mixtures of PSA-9 and ELVAX 240 were prepared with the
levels of ELVAX 240 shown in Table 27 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 43-44. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 27.
28TABLE 27 Level of ELVAX 240 Solvent Extraction Example (weight %)
Test Result C39 10 Fail C40 15 Fail
Comparative Examples C41-C.sub.42
[0105] Mixtures of PSA-8 and ELVAX 450 were prepared with the
levels of ELVAX 450 shown in Table 28 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 28.
29TABLE 28 Level of ELVAX 450 Solvent Extraction Example (weight %)
Test Result C41 10 Fail C42 15 Fail
Comparative Examples C43-C.sub.44
[0106] Mixtures of PSA-8 and ELVAX 660 were prepared with the
levels of ELVAX 660 shown in Table 29 and hot melt coated to form
films as described in U.S. Pat. No. 6,063,838 (Patnode, et al)
Examples 1-17. The solvent extraction properties of the films were
determined as described in the Solvent Extraction Test method
above. The results are shown in Table 29.
30TABLE 29 Level of ELVAX 660 Solvent Extraction Example (weight %)
Test Result C43 10 Fail C44 15 Fail
Example 42
[0107] A stretch removable First Aid Dressing (FAD) sample was made
by laminating with thumb pressure at room temperature a strip
(2.54-cm.times.7.6-cm) of a perforated polymer film backing to a
strip (2.54-cm.times.7.6-cm) of the adhesive described in Example
20, with the fibers perpendicular to the long axis of the sample.
The film backing comprised 60% ethylene/vinyl acetate copolymer,
35% linear low density polyethylene, 5% stabilizers and other
additives (PGI Product No. 6012, Polymer Group, Inc., Gainesville,
Ga.); and the film had a basis weight of 1.15 oz/yd.sup.2 (27
g/m.sup.2), was 5-mils (0.13-mm) thick, and had oval-shaped holes
(approximately 0.2-mm width x 0.3-mm length in the greatest
dimensions) with the length dimension of the oval holes oriented
parallel to the machine direction of the film. The film had about
530 holes/cm.sup.2 arranged in a pattern of staggered lines.
[0108] The FAD sample was evaluated for ease of removal by adhering
the sample with finger pressure to the forearm of a human subject,
waiting 60 minutes, and then removing by pulling one end of the
sample and stretching the sample at about a 35.degree. angle to the
plane of the forearm. Very little force was required to stretch the
backing and to remove the sample painlessly from the skin and hair
of the forearm.
Example 43
[0109] A polyurethane backing (melt-blown nonwoven fibrous web
comprised of three-layer polymeric fibers having a center layer of
blended polyethylene and Kraton.TM. PSA, and outer layers of
polyurethane; prepared as described for Backing Sample 16 in U.S.
Pat. No. 6,107,219 (Joseph et al.)) was perforated with a metal die
to provide parallel rows of holes separated by 3.8 cm. The holes
were rectangular in shape (1.75-mm.times.0.07-mm) and the space
between holes within a row was 0.7 mm. The polyurethane backing had
one side rougher than the other due to the collection technique
used during the melt-blown process.
[0110] A stretch removable FAD sample was made by laminating with
thumb pressure at room temperature a strip (2.54-cm.times.7.6-cm)
of the perforated polyurethane backing to a strip
(2.54-cm.times.7.6-cm) of the adhesive described in Example 20,
with the fibers perpendicular to the long axis of the sample. The
"rough" side of the backing was adjacent the adhesive layer. A
1.8-cm.times.2.5-cm gauze pad was attached to the adhesive layer in
the center of the sample and the holes had been pre-cut such that
the rows began 6 mm from each end of the sample.
[0111] The FAD sample was evaluated for ease of removal by adhering
the sample with finger pressure to the forearm of a human subject,
waiting 10 minutes, and then removing by lifting and stretching the
gauze pad at about a 90.degree. angle to the plane of the forearm.
Very little force was required to stretch the backing and to remove
the sample painlessly from the skin and hair of the forearm. During
stretching and removal, the backing was observed to break and to
delaminate from the adhesive layer.
Example 44
[0112] A paper backing (Hammermill Laserprint paper (0.11-mm
thick), Product No. 00460-4, International Paper, Memphis, Tenn.))
was perforated with a metal die to provide parallel rows of holes
separated by 6.35 cm. The holes were rectangular in shape
(1.75-mm.times.0.07-mm) with the long sides of the holes oriented
in the direction of the rows and the space between holes within a
row was 0.7 mm.
[0113] A FAD sample was made by laminating with thumb pressure at
room temperature a strip (2.54-cm.times.7.6-cm) of the perforated
paper backing to a strip (2.54-cm.times.7.6-cm) of the adhesive
described in Example 20, with the fibers perpendicular to the long
axis of the sample. A 1.8-cm.times.2.5-cm gauze pad was attached to
the adhesive layer in the center of the sample and the holes had
been pre-cut such that the rows began 6 mm from each end of the
sample.
[0114] The FAD sample was evaluated for ease of removal by adhering
the sample with finger pressure to the forearm of a human subject,
waiting 10 minutes, and then removing by pulling one end of the
sample and stretching the sample at about a 35.degree. angle to the
plane of the forearm. Very little force was required to stretch the
backing and to remove the sample painlessly from the skin and hair
of the forearm. During stretching and removal, the backing was
observed to break and to delaminate from the adhesive layer.
Example 45
[0115] A stretch removable FAD sample was made by laminating with
thumb pressure at room temperature a sheet (10.2-cm square) of a
Rayon/Nylon nonwoven backing [thermal spunbond Rayon/Nylon nonwoven
fabric, Fiber No. 149-245, basis weight=25 g/m.sup.2, Veratec,
Walpole, Mass.] to a sheet (10.2-cm square) of the adhesive
described in Example 20, with the fibers perpendicular to the long
axis of the sample. The sheets were oriented such that the adhesive
layer, when subsequently stretched for removal, would be stretched
in a direction parallel to the machine direction of the adhesive
layer. Prior to lamination, the adhesive sheet was covered along
one edge with a strip of paper that could serve as a handle for
grasping the adhesive layer alone.
[0116] The resulting laminate was cut into a 2.54-cm.times.7.6-cm
FAD sample and adhered with thumb pressure onto a mirror-finished
steel plate with the paper handle allowed to extend over the end of
the plate. The paper handle of the sample was finger-grasped and
stretched in the plane of the adhesive-backing interface at a rate
of about 150 cm/min. Upon stretching, the adhesive released from
between the plate surface and the backing.
Example 46
[0117] A FAD sample was made by laminating with thumb pressure at
room temperature a strip (2.54-cm.times.7.6-cm) of a polypropylene
backing [melt-blown nonwoven polypropylene (basis weight 20
g/m.sup.2), Kimberly-Clark, Irving, Tex. ] to a strip
(2.54-cm.times.7.6-cm) of the adhesive described in Example 20. A
1.3-cm piece of the adhesive/backing laminate was gathered in the
middle of the strip in such a way that a fold was made
perpendicular to the greatest length of the strip. A
1.8-cm.times.2.5-cm gauze pad was attached to the adhesive layer in
the center of the sample.
[0118] The FAD sample was evaluated by adhering the sample with
finger pressure to the forearm of a human subject, waiting 10
minutes, and then using the fold in the FAD as a handle, removing
by lifting and stretching the gauze pad at about a 90.degree. angle
to the plane of the forearm. Very little force was required to
stretch the backing and to remove the sample painlessly from the
skin and hair of the forearm. During stretching and removal, the
backing was observed to break and to delaminate from the adhesive
layer.
Example 47
[0119] A FAD sample having a center fold and a gauze pad was made
as described in Example 46, except that the polyurethane backing
(as described in Example 43) was used in place of the polypropylene
backing. The sample was evaluated as described in Example 46.
During stretching and removal, the backing was observed to
delaminate from the adhesive layer.
Example 48
[0120] A FAD sample having a center fold and a gauze pad was made
as described in Example 46, except that the adhesive described in
Example 28 was used as the adhesive. The sample was evaluated and
the same results obtained as described in Example 46.
Example 49
[0121] A blend of 80 parts of PSA-7 and 20 parts of ATTANE 4202
were mixed in a BRABENDER mixer (C.W. Brabender Instruments, South
Hackensack, N.J.) at 140.degree. C. to 150.degree. C. for 8 to 10
minutes. The resulting mixtures were hot melt coated between two
release liners at 150.degree. C. using a HAAKE single screw
extruder (commercially available from Haake, Inc.; Paramus, N.J.)
equipped with a draw die. The resulting PSA film had a thickness of
127 micrometers and was laminated to a PCL backing of thickness
listed in Table 30 (prepared by solvent coating a 20% solids
solution of PCL in toluene onto a release liner and drying at
70.degree. C. for 10 minutes) to make a tape. The stretch release
properties of the tape was determined as described in the Stretch
Release Test Method above except that samples were tested not only
in the machine direction but also in the cross web direction and at
45.degree. to the machine direction. The results of the laminated
samples as well as the PSA film not laminated to a backing are
shown in Table 30.
31TABLE 30 Stretch release Stretch release Stretch release Force in
the Force in the Force 45.degree. to PCL backing machine cross
machine machine thickness direction direction direction Example
(micrometers) (N/dm) (N/dm) (N/dm) 49-1 0 18.2 9.6 13.8 49-2 13
37.2 30.6 36.8 49-3 25 39.6 21.9 25.6 49-4 38 36.8 26.7 32.6
[0122] Various modifications and alterations of the present
invention will become apparent to those skilled in the art without
departing from the spirit and scope of the invention.
* * * * *