[0001] This invention relates to a pressure sensitive composite material and more particularly
to a flame retardant, printable, solvent, fuels and lubricating fluids resistant,
material for use at elevated temperatures.
[0002] The material of the present invention is adapted particularly for use in aircraft
and ships as an identification tape/label in various applications such as electrical
wiring identification, hydraulic line identification, etc. In these applications the
tape/label is usually wrapped around electrical wire bundles or hydraulic lines which
may be exposed to hydraulic line fluids, oils, greases, fuels, and the like.
[0003] There has been a growing need for materials which are resistant to attack from petroleum
based products such as oils, greases, hydraulic fluids, jet engine fuels, ethylene
and proplyene glycol and the like. These tape/label materials must be able to meet
high performance standards under different environmental conditions. As such, a tape
or label material must be flame retardant so that it is self-extinguishing when flame
is removed from it. The material must also be pressure sensitive and self-adhesive
as well as having good adhesive properties to other materials. In addition, such material
must be capable of reliable service up to 260°C while being solvent, fuels and lubricating
fluids resistant. Upon meeting all of these requirements, the material must also be
capable of being printed upon by impact and laser marking machines. All of these requirements
must be contained in a material which in many instances is no more than 1 mm thick.
[0004] In responding to these requirements, the prior art has attempted to meet the needs
of the industry with the use of polyvinylfluorides, polytetrafluoroethylenes and polyimide
materials. For the most part, these prior art materials in various forms do not meet
all the high performance standards as set forth above and as required by the industry.
To begin with, most of the prior art materials are not capable of use up to 260°C.
Many of them are not flame-retardant because they are combustible after the flame
has been removed. In other instances, the prior art materials are not solvent fuels
and lubricating fuels resistant. In many instances the materials that have been used
in the prior art are not capable of being printed upon by impact or non-impact printing
methods such as laser marking machines and the like.
[0005] Heretofore, in the prior art, the balance between printable materials and solvent,
fluids and lubricating fluids resistant materials has always required a compromise.
When one material was highly printable it was not solvent, fuels and lubricating fluids
resistant. When the material was solvent, fuels and lubricating fluids resistant,
it was not capable of being printed upon. Since the materials for these particular
tape/label applications must meet both of these requirements, the prior art materials
were deficient.
[0006] In view of the foregoing, one of the objects of the present invention is to provide
a new and improved pressure sensitive composite material for use under particular
environmental conditons.
[0007] Another object of the present invention is to provide a new and improved pressure
sensitive composite material for use in temperatures up to 260°C, at which temperatures
the material is solvent, fuels and lubricating fluids resistant, non-flagging and
flame retardant, while at the same time being printdable by impact and non-impact
printing methods.
[0008] Still other objects and advantages of the invention will be apparent from the following
specification. The invention accordingly comprises a product possessing the features,
properties and the relation of components which will be exemplified in the product
hereinafter described. The scope of the invention will be indicated in the claims.
[0009] For full understanding of the invention, reference is had to the following description.
[0010] A practical embodiment of the invention is shown, somewhat diagrammatically, in the
accompanying drawing wherein:
Fig. 1 is a plan view of a release liner on which are mounted a plurality of labels
made from the pressure sensitive composite material of the instant invention, and
Fig. 2 is a section taken on line II-II of Figure 1.
[0011] The product, 10, of the instant invention, is composed of three principal components,
a substrate 12, an adhesive coating 14 and a resin coating 16. The substrate 12 is
usually of thicknesses less than 1 mm and preferably in the range of .025 mm to about
.25 mm This substrate is made up of a, non-woven polyamide, however a non-woven fiberglass
mat may also be used as the substrate material.
[0012] The adhesive coating or layer 14 is placed on one side of the substrate. This adhesive
layer must be capable of performing under the extreme conditions of high temperature
and still be solvent, fuels and lubricating fluids resistant. To this end, it is contemplated
that the adhesive coating layer 14 will be a polyacrylate and it will be applied to
one side of the substrate 12. In addition to the polyacrylates, polysiloxanes, polyurethanes
and resin modified natural and synthetic rubbers can be used. The resin modified natural
and synthetic rubbers are carefully chosen so that they have the desired adhesive
properties, but they are principally chosen from the group consisting of the styrene-butadiene
polymers, polyisoprene, polychloroprene and butadiene-acrylonitrile polymers. The
adhesive coating is applied to one side of the substrate by appropriate coating methods
and apparatus and they may be applied separately or simultaneously with the resin
coating 16 which is put on the other side of the substrate material 12. (that is the
side opposite the adhesive coating side).
[0013] The resin coating 16 must be compatible with the substrate material and the adhesive
layer while being capable of meeting the stringent, high performance requirements
in service, that it be solvent, fluids and lubricating fluids resistant, capable of
service up to 260°C in relatively thin sections, of below 1 mm in thickness, and at
the same time be capable of being printed upon by impact and laser printing methods.
This resin coating 16 is chosen from the polyacrylates, polyesters, polyurethanes
and butadiene-acrylonitrile polymers. The resin can also be chosen from solvent resistant
resins such as polychloroprene and the chlorosulfonated-polyethylenes.
[0014] The thickness of the adhesive coating 14 is preferably between .01 mm to about .10
mm while the resin coating 16, preferably ranges in thickness from about .001 mm to
about .075 mm. The adhesives chosen for use as the adhesive coating may be partially
cross-linked by appropriate chemical and/or ionizing radiation cross linking techniques.
To enhance the solvent resistance, etc., the resins that are chosen for use as the
top coating can be either the curable types of resin or the non-curable types. A blending
of curable and non-curable resins may be used to obtain the optimum balance of properties.
In any event, the curable resins may be partially cross-linked either chemically or
by ionizing radiation.
[0015] Release liner material 18 is calendered paper and the like and is applied to the
adhesive coating layer 14 thus facilitating the peel off of the composite material
10 when it is manufactured in sheet and roll form. The release liner can be of considerable
thickness compared to the composite material 10.
[0016] If the material 10 needs to be color coded, the resin 16 can be provided with an
appropriate color pigment which will be compatible with the resin coating chosen for
the particular use. In any event, it is the product 10 composed of the substrate 12,
the adhesive coating 14 and the resin coating 16, which results in the unique properties
of the composite material.
Modes for Carrying Out the Invention
[0017] Examples of laminate materials prepared in accordance with the teachings of this
invention to meet the requirements noted above are as follows:
[0018] The following resin solutions were prepared for use in the instant invention:

EXAMPLE #1
[0019] A .05 mm polyamide paper (Nomex Aramid Paper Type 410) was coated on one side with
solution "A" using an applicator roller and doctoring off excess with wire-wound Meyer
Rod.
[0020] The coated polyamide paper was dried in a conventional air circulating oven. The
coating of the resin was .01 mm when dry. The polyamide paper was then coated on the
other side with a polyacrylate adhesive (H & N Chemical Company's Polyad 130). The
adhesive was applied with a reverse roll coater and deposited at 0.04 mm dry thickness.
The adhesive was dried and cured and the completed composite was then wound up against
a 60# silicone coated release paper.
[0021] Testing showed this composite to have excellent printability and good solvent, fuels
and lubricating fluids resistance and good printability.
EXAMPLE #2
[0022] Example #2 was prepared in the same manner as example #1 except that the resin solution
B was used. The dry thickness for both the resin and adhesive were the same asin example
#1.
[0023] Testing showed this composite to have excellent solvent, fluids and lubricating fluids
resistance printability.
EXAMPLE #3
[0024] Example #3 was prepared in the same manner as example #1 except a .075 mm Nomex polyamide
paper was used and Solution C was used.
[0025] Testing showed an excellent balance of printability and solvent fuels and lubricating
fluids resistance.
[0026] All examples (1, 2 and 3) were stable and useful up to 260°C. Although none of adhesive
coatings or adhesives were flame retardant per se, all laminates passed the flame
retardant requirements.
[0027] It will thus be seen that the objects set forth above among those made apparent from
the preceeding description can be efficiently attained and since certain changes may
be made in the above product without departing from the spirit and scope of the invention,
it is intended that all matter contained in the above description shall be interpreted
as illustrative and not of limiting sense. It is also to be understood that the following
claims are intended to cover all of the generic and specific features of the invention
herein described. Particularly it is to be understood that in the claims set forth
below, ingredients or compounds recited in the singular are intended to include compatible
mixtures of such ingredients wherever the sense permits.
1. A composite material comprising,
a non-woven substrate chosen from the group consisting of polyamide and fiberglass
mat,
an adhesive coating on one side of said substrate chosen from the group of pressure
sensitive adhesives consisting of polyacrylates, polysiloxanes, polyurethanes and
resin modified natural and synthetic rubbers such as styrene-butadiene polymers, polyisoprene,
polychloroprene, butadiene-acrylonitrile polymers,
a resin coating for the other side of the substrate chosen from the group consisting
of polyacrylates, polyesters, polyurethanes, butadiene-acrylonitrile polymers, and
solvent resistant resins such as polychloroprene and chlorosulfonated-polyethylenes.
2. The material of claim 1 further defined in that the adhesive coating is at least
partially cross-linked.
3. The material of claim 1 further defined in that the substrate ranges in thickness
from about .025 mm to about .25 mm, the adhesive coating ranges in thickness from
about .01 mm to about .10 mm and the resin coating ranges in thickness from about
.001 mm to about .075 mm.
4. The material of Claim 3, further defined in that the adhesive coating is at least
partially cross-linked.
5. The material of claim 1 further defined in that the product is provided with a
release liner which is placed over the adhesive coating.