Note: Descriptions are shown in the official language in which they were submitted.
93~
This invention relates to coverings for tool handles,
and, in particular, to a spiral wrapping of an
adhesive-backed tapeO
Various coverings have been suggested, and a few have
been used with varied success, as non~slip grips for
handles o working and sporting tools. Among these are
moisture absorbent materials such as terricloth and
plastic sponge; moisture repellant materials such as
rubber and plastic tapes; leather; and the like.
In my prior United States patents 4,098,506 and
4,174,109, I disclose the use of a reticulated plastic
foam which can be placed over the handle of tools as a
sleeve, including the application of the material as an
adhesive-backed tape. Conventional reticulated foam,
however, is of very low density and this material thus
has limited tension and shear strength and must be used
in appreciable thickness in the uncompressed state.
Because of its limited tear resis~ance, I prevlously
~ound it desirable to overlay the abutted edgesr i.e.,
the seams, of adjacent tape wraps with an adhesively
backed tape in the manner described in U.S. Patent No.
4,174,109.
Handle wrappings of lesser thicknesses are desirable,
and, preferably, such wraps should be provided without
the need for a tape overlay along its edge seams.
3~i8
I have now found that a particular form of
reticulated foam can be treated to provlde a very
superior handle wrap. This form of reticulated foam is
one which has been heat pressed to a permanent,
approximately 30 to 70 percent, compression. The
resultant foam still retains its open cell wall
structure and has a non-woven fibrous structure,
however the size and spacing between the fibers of the
structure is substantially decreased by the heat
compression of the foam. This foam is provlded with a
pressure sensitive adhesive layer that is overlayed
with a backing which is stripped from the tape when the
tape is applied to a sur~ace. This tape is modi~ied
for use in my invention by the heat sin~ering of
narrow-width edge bands~ one at each side of the band,
coextensively with its length. Preferably the ends of
the tape are cut on a bias angle from 5 to about 35
degrees and, most preferably, the opposite end edges
are parallel and are cut at a bias angle whlch is equal
to the helical angle of the spiral wrap when appIied to
a tool handle. In its preferred embodiment, the tape
also includes at least one lateral tab distally
projecting rom said tape along the bias angle and, in
application, this tab is overlayed by the adjacent
spiral wrap of the tape, thereby reducing the tendency
of the ends of the spiral wrap to fray or loosen in
use.
The invention will be described with reference to the
figures of which:
FIGURE 1 illustrates the tape of the inventionS
FIGURE 2 is a sectional view along lines 2~2 of
FIGURE l;
FIGURE 3 illustrates the initial applica~ion of the
tape of the inven-tion to a tennis handle;
FIGURE 4 illustrates the completed spiral wrapping of
the tape of the invention; and
FIGURE 5 is a sectional view along lines 5-5 of
FIGURE 4.
Referring now to FIGURE 1, the invention is shown as
a narrow-width tape 10 o extended length, havlng
longitudinal edges 12 and 14 and end edges 16 and 18
whi~h are cut at equal bias angles indicated a~ 20.
The bias angle 20 of the ends of tape 10 should be
equal to the helical angle of winding of the tape on a
tool handle as described in greater detail hereinafter.
The tape has its longitudinal edges 12 and 14 treated
along narrow width band~ shown at 22 and 24. The bands
are heat sintered surfaces achleved by passing a hot
iron over the edges of the tape, typ.ically the sur~aces
are heated to a temperature o from ~00 to about 375
degrees F., most preferably, about 325 degrees F~
The tape 10 is also processed to provide at least
one, narrow-width, longitudinal band 26 intermediate
its width, preferably at equal spacing between the edge
bands 10 and 14~ The continuous narrow-widtn band ~6
is imparted in the tape by heat treatment, by passing a
hot iron surface across the surface of the tape; the
aforementioned temperatures being suitable and
preferred for this use also.
Referring now to FIGURE 2, the cross sectlon of the
tape is illustrated. As thus shown, the tape is of a
limited thickness, typically from about 1/16 to about
3/8 inch, most preferably about 1/8 inch thic~ness.
The edges are provided with the longitudinal, heat
sintered bands 12 and 14 and, the tape is of slightly
reduced thickness, resulting f rom this treatment. The
tape similarly has a, narrow, central band 26 of
slightly reduced thickness, also resulting from heat
sintering treatment of the surface of the tape in this
region. Preferably~ the sin~ering along the edges of
the tape provides a bevel to the top edge of the tape
~3~5~
so that when the edge is abutted against a like edge, a
V-groove results. Also preferably, the central band 26
is formed as a V~groove o~ substantially the same
dimensions as that formed by the abutting adjacent
edges of the tape so that the central band 26 and the
edge seams have the same appearance and feel
The undersurface 27 of the tape has a pressure
sensitive adhesive coating and this coating is overlald
by a protective backing 34~ shown in exaggerated
thickness ln the illustration of FIGURE 2.
The tape of the invention i5 a reticula~ed plastic
foam which is heat pressed to reduce its thickness
approximately 30 to 70 percent. The reticulated
plastic foam is a plastic material havlng at least 50,
and, preferably, 100 percent open cells~ The material
has a reticulated, three dimensional structure and is
basically a non-woven fibrous material obtained by the
reticulation treatment of an open cell, cellular
pla~tic foam. The plastic material is characterized by
a low capillary structure and a low wa~er holding
capacity. The maximum amount of water retained by the
material is generally no greater than about 20 volume
percent and, preferably~ is no greater than about 10
volume percent. This limited water holding capacity
ensures that the ma~erial readily breathes in use and
moisture is expelled rather than retained~ thereb~
~ ~ 3 ~3~ 6
retaining the natural balance of the tool and firmness
in the grip of a user.
The reticulated foam can be obtained by various
manufacturing methods such as the consolida~ion of a
loose mat of randomly oriented fibers such as polyester
fibers, with an adhesive such as an aqueous polyvlnyl
acetate or synthetic rubber latex. Most preferably,
the material is obtained by the reticulation treatment
of opened celled plastic foam, preferably polyurethane
foam. This material is obtained by the post-formation
heat treatment of a polyurethane or other plastic foam
to rupture the cell walls of the foam, leavlng a
reticulated or skeleton structure which closely
resembles a non-woven fibrous mat structure.
A preferred class of plastic oam for reticulation
treatment is a flexible, opened-cell cellular
polyurethane foam. There are two general types of
polyurethane foam which are commonly available; these
are ether-base and ester-base polyurethane ~oams. 0
these, the ester-base polyurethane foams are most
preferred for use as the open-celled or reticulated
materials because of their high resistance to OilS,
moistures and solvents. Generally, the` flexible,
open-cell, cellular plastic foam or reticulated oam in
its uncompressed state has a low density, e.g~, from
about 0.1 to about 6 pounds per cubic foot.
9~
The uncompressed reticulated foam is further treated
or processed to pxovide the foam useful in this invention
by heat pressing to compress the foam to approximately 30
to 70 percent of its original thickness. This pressure
application is accompanied by heating of the foarn-to a
permanent deformation temperature, typically to a tempera-
ture of about 225 -to 350 degrees F., at which temperature
the foam undergoes a plastic deformation and is cooled in
its compressed state to a permanent compressed or deformed
condition. The resulting treatment does not significantly
decrease the porosity or open-celled nature of the foam but
does, however, substantially increase its -tear resistance
and durability.
Following the heat pressing of the foam to the partially
and permanently cornpressed state, the foam can be coated
with a suitable pressure sensitive adhesive along one sur-
face. The surface to be coated is first overlaid with a
thin plastic f:ilm, e.g., Mylar, a registered trademark,
that is bonded to the foam with a permanent adhesive,
thereby providing a non-permeable base for the pressure
sensitive adhesive. Pressure sensitive adhesives are com-
monly a coating of an elastomer, referred to as a mass coat,
which has a desirably high tacky surface. Usually the
elastomer is applied to the back of a substrate in a
volatile solvent which is inert to the substrate.
~arious elastomers which have
.~ .,.
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the property of a tacky surface can be applied to the
foam such as: natulral rubber; styrene-butadiene
rubber; styrene-hutadiene-styrene bloc~ copolymers;
neoprene, etcO These elastomers are dissolved in a
suitable volatile solvent such as aliphatic and
aromatic hydrocarbons. The tac~y property of the
resultant coating of the elastomer can be enhanced by
inclusion of adhesive materials such as terpene resins,
phenolic resins, partially hydrogenated rosin esters,
etc.
The last coat of the pressure sensitive adhesive is
then overlayed with a protective bac~ing 34 which can
be formed of various materials such as wax or silicone
coated paper, polyethylene, polyvinyl chloride and the
like.
The tape 10 of the invention prleerably is provided
with at least one lateral tab 28 r also formed of the
reticulated foam that comprises an integral projectlon
distally located on the tape. The lateral tab projects
at the same bias angle 20 of the tape. Preferably,
this lateral tab 28 is heat pressed and sintered to
reduce its thickness to appxoximately 20 to 50 percent
of the thickness of the main body of the tape 10 as
shown in FIG~RE 2. If desired, a similar narrow
lateral tab 30 can be located at the opposite end of
the tape 10 as shown in the phantom lines of FIGURE 1.
~3~ 9
Referring now to FIGURE 3, there is illustrated a
portion of a handle 36 of a tool such as a tennis
racket handle. This handle 36 has a typical or
conventional end rib 38 of slightly greater diameter
than the handle. The tape 10 of the invention is used
by peeling the protective backing 34 from the adhesive
coated tape and applying the tape to the handle of the
racket, in this application, the tape is preferably
applied with the lateral tab 28 and the end edge 18 of
the tape overlying the raised rim 38 of the handle.
The remainder of the tape is layed about the handle so
that the s~cceeding wrap of the tape overlies the tab
28, as shown. For this purpose9 the distance X shown
ln FIGURE 1 should be approximately the circumference
of the base of the handle 36.
Referring now to FIGURE 4, the tape 10 is shown as a
completed spiral wrapping 40 about handle ~6 of a
tennis racket. The adjacent wraps of the tape form a
continuous, helical~ abutting seam 42 be~ween the edges
12 and 14 of the adjacent wraps of the tape. The
continuous, spiral seam 42 is shown repeatedly in
FIGURE 4 and the adjacent, sintered, longitudinal edges
22 and 24 cooperate to form a narrow-width channel 46
which is shown in sectional view in FIGURE 5. The
lateral tabs distally carried on the tape are shown as
elements 28 and 30 which are overlayed by the adjacent
wrapping. The wrapping is applied to the tape at a
helical angle ~0 which is the same angle 20 of the bias
cut of ends 16 and 18 of the tape. The tape of my
invention can thus be used without any adhesive bonding
or tape, other than the adhesive bac~ing on the
undersurface of the tape. The heat sintering treatment
of the longitudinal edge bands 22 and 24 of the tape
imparts a very subs~antial tear strength to the tape
and greatly improves its dimensional stability so that
the edge seam 42 is stable durlng use and does not
readily tear. The tape can be readily applied to any
regular or irregular shaped handle and the la~eral tab
such as 28 can be used to an advantage to avoid any
fraying or loosening of the ends of the spiral
wrapping.
The porous nature of the tape surface used in tne
invention provides a course or rough exterior surface
that can be readily grasped by a user WithOU~
discornfort and with a maximum of frictional engagement.
This frictional engagement can be enhanced by further
treatment of the plastic foam u~ed in the invention to
deposit from about 5 to 100 weight percent, or greater,
of an abrasive solid powder havlng a maximum particle
si~e less than about 200 mesh. Typical and suitable
materials for this comprise various powdered minerals
such as silicas, clays, alumina, etc~ A very suitable
material is fumed sili~a such as material commerc ally
9, ~, ~ o~o~
available under the designation of Santomerse~Z or Cab-
3 ~ ~3
~ J ~ ~ - ~ ~ ~ 11
O-Si~ These materials can be applied to the tape by
suspending them in a suitable, volatile carrier such as
alcohol and spraying ~he material on the surface of the
tape or dusting or brushing of the dry powder or
carrier-suspended powder across the surface of the
tape. Since the tape has an open-celled, skeletal
structure, it has a very high ahsorbency for abrasive
materials such as those aforedescribed~ The presence
of even slight amounts of such materials greatly
enhances the frictional properties of the surEace of
the tape, and the high porosity of the tape permits a
high loading of the abrasive solid such that the solid
remains in the tape throughout its useful life.
The greatly reduced thickness of the tape of the
invention provides a gripping surface which is of no
significantly greater thickness than the thickness of
the uncoated tool handle. This retains the kinesthetic
perception of the tool when grasped in a user's hand.
Additionally, the material is of very low density and
therefore has a minimal weight ef~ect on the tool and
does not alter the natural balance of the tool. Since
the reticulated foam, even when permanently compressed,
still maintains a non-capillary porous, open-celled
structure, moisture and volatile oils which develop on
the hand of the user are readily dlssipated from the
material and do not accumulate in the ma~erial to
affect its usefulness.
3~
The invention has been described with reference to
the illustrated and presently preferred embodiment
thereof. It is not intended that the inventlon be
unduly limited by this description of the illustrated
embodiment. Instead, it is intended that the invention
be defined by the means, and their obvious equivalents,
set forth in the following claims.
