GABBAY JEFFREY (IL)
US4900618A | 1990-02-13 | |||
US4999240A | 1991-03-12 | |||
US5017420A | 1991-05-21 | |||
US5399425A | 1995-03-21 | |||
US5405644A | 1995-04-11 | |||
US5411795A | 1995-05-02 |
1. | A process comprising the steps of: (a) providing a metallized textile, said metallized textile comprising: (i) a textile including fibers selected from the group consisting of natural fibers, synthetic cellulosic fibers, regenerated protein fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, vinyl fibers, and blends thereof, and (ii) a plating including materials selected from the group consisting of metals and metal oxides, said metallized textile characterized in that said plating is bonded directly to said fibers; and (b) incorporating said metallized textile in an article of manufacture. |
2. | The process of claim 1, wherein said article of manufacture is an acaricide. |
3. | The process of claim 2, wherein said article of manufacture is a bedsheet. |
4. | The process of claim 1 , wherein said article of manufacture gicide. |
5. | The process of claim 4, wherein said article of manufacture rment. |
6. | The process of claim 4, wherein said article of manufacture od storage container. |
7. | The process of claim 1 , wherein said article of manufacture ctericide. |
8. | The process of claim 7, wherein said article of manufacture rment. |
9. | The process of claim 7, wherein said article of manufacture andage. |
10. | The process of claim 7, wherein said article of manufacture interior furnishing. |
11. | The process of claim 10, wherein said article of manufacture or covering. |
12. | The process of claim 11 , wherein said article of manufacture rpet. |
13. | The process of claim 10, wherein said article of manufacture ll covering. |
14. | The process of claim 10, wherein said article of manufacture rticle of furniture. |
15. | The process of claim 10, wherein said article of manufacture rtain. |
16. | The process of claim 7, wherein said article of manufacture od storage container. |
17. | The process of claim 1 , wherein said article of manufacture or. |
18. | The process of claim 17, wherein said article of manufacture armor. |
19. | The process of claim 1 , wherein said article of manufacture lectrical device. |
20. | The process of claim 19, wherein said article of manufacture ttery. |
21. | The process of claim 1 , wherein said article of manufacture lectrode. |
22. | The process of claim 1 , wherein said article of manufacture ntistatic device. |
23. | The process of claim 22 , wherein said article of manufacture rpet. |
24. | The process of claim 22 , wherein said article of manufacture olstery. |
25. | The process of claim 1 , wherein said article of manufacture io frequency shield. |
26. | The process of claim 1 , wherein said article of manufacture dar reflector. |
27. | The process of claim 1 , wherein said article of manufacture e retardant. |
28. | The process of claim 1 , wherein said article of manufacture e barrier. |
29. | The process of claim 1 , wherein said article of manufacture rment. |
30. | The process of claim 1, wherein said article of manufacture hicle. |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to textiles and, more particularly, to
applications of a metallized textile produced by binding a full or partial
metal or metal oxide plating to the fibers of a textile.
There are a variety of applications for which a textile with a full or
partial metal or metal oxide plating bonded to the fibers thereof would be
useful. These include:
1. Acaricide
Beds commonly are infested by tiny mites. These mites eat bacteria
and fungi that grow on epidermal scales shed by people who sleep in the
beds. Fragments of dead mites, and mite excreta, are allergens, to which
asthmatics and people with dust allergens are sensitive. It has been found
that some metals and metal oxides, notably Cu, CuO, Ag and Ag : 0, repel
mites.
The conventional method for making textiles inhospitable to mites
is to treat the textiles with an organic acaricide such as benzyl benzoate.
For example, Bischoff et al. , in U.S. Patent No. 4,666,940, teach an
acaricide that includes benzyl benzoate and a solid powder carrier whose
particles are of a size suitable for ingestion by the mites. These acaricides
must be replaced every time the textile is laundered. Thus, Bischoff et al.
recommend using their acaricide on textiles, such as carpets and
upholstery, that are not laundered frequently. An inherently acaricidal
bedsheet would keep a bed free of mites, even after multiple launderings,
without the need to reapply acaricide to the bedsheet.
2. Bactericide and Fungicide
Some metal oxides, notably ZnO, are well known as fungicides.
Before the introduction of antibiotics to medicine, silver metal sometimes
was used as a bactericide and bacteriostat. Textiles with inherent
bactericidal and fungicidal properties have obvious applications in settings,
such as hospitals and similar institutions, where it is important to maintain
aseptic conditions.
Bactericidal agents used heretofore in textiles include complexes of
zirconyl acetate with inorganic peroxides (Welch et al. , U.S. Patent No.
4,115,422), metal cations contained in zeolite particles (Hagiwara et al.,
U.S. Patent No. 4,525,410), and quaternary ammonium salts (White et al. ,
U.S. Patent No. 4,835,019; Hill et al., U.S. Patent No. 5,024,875; Zhao
et al. , U.S. Patent No. 5,254,134). These are not totally satisfactory,
being specific to a particular textile (such as the polyamide yarn of White
et al.), or being subject to eventual loss of activity by chemical
decomposition, a process often hastened by laundering.
3. Body Axmor
Lightweight armor commonly is made of multiple layers of fibers
such as the fiber produced by E. I. DuPont de Nemours and Company
under the trademark Kevlar. It has been found that the effectiveness of
Kevlar armor is enhanced by the inclusion of ceramics such as A1,0 3 , in
the form of plates, or, as taught by Clausen in U.S. Patent No. 4,292,882,
in the form of particles interspersed among the Kevlar fibers. These
ceramics enhance the resistance of the armor to penetration by bullets, by
abrading and gripping the bullets. This action would be enhanced further
in armor in which the A1,0 3 has an even more intimate connection to the
Kevlar fibers.
The methods known in the prior art for bonding a metal or a metal
oxide to a textile generally require that the metal or its oxide be bonded
indirectly to the textile. For example, the metal may be reduced to a
powder and suspended in a binder. The binder-metal mixture then is
applied to the textile, with the binder, and not the metal, bonding to the
textile. Alternatively, the metal is reduced to a powder, an adhesive is
applied to the textile, and the metal powder is spread on the adhesive.
Examples of both such methods may be found in U.S. Patent No.
1,210,375, assigned to Decker. These methods are less than satisfactory
for the above applications, for at least two reasons. First, the carrier or
adhesive may entirely encapsulate the metal or metal oxide powder
particles, inhibiting their contact with mites, fungi, and bacteria, and
making the textile useless as an acaricide, fungicide, or bactericide.
Second, multiple launderings tends to weaken the binder or adhesive and
loosen or remove the particles.
Two notable exceptions to the general rule that metals and metal
oxides have not heretofore been bonded directly to textiles are nylon
textiles and polyester textiles, which may be plated with metals using
standard electroless plating processes for plating plastics. The specific
electroless plating methods known to the art are restricted in their
applicability to only certain plastics, however. In particular, they are not
suited to natural fibers, nor to most synthetic fibers.
There is thus a widely recognized need for, and it would be highly
advantageous to have, a textile with a full or partial metal or metal oxide
plating directly and securely bonded to the fibers thereof, for use in the
applications listed above. The scope of the present invention includes
these and other applications, which are listed below.
SUMMARY OF THE INVENTION
According to the present invention there is provided a process
comprising the steps of: (a) providing a metallized textile, the metallized
textile comprising: (i) a textile including fibers selected from the group
consisting of natural fibers, synthetic cellulosic fibers, regenerated
fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, vinyl fibers,
and blends thereof, and (ii) a plating including materials selected from the
group consisting of metals and metal oxides, the metallized textile
characterized in that the plating is bonded directly to the fibers; and (b)
incorporating the metallized textile in an article of manufacture.
In the context of the present invention the term "textile" includes
fibers, whether natural (for example, cotton, silk, wool, and linen) or
synthetic, yarns spun from those fibers, and woven, knit, and non- woven
fabrics made of those yarns. The scope of the present invention includes
all natural fibers; and all synthetic fibers used in textile applications,
including but not limited to synthetic cellulosic fibers (i.e. , regenerated
cellulose fibers such as rayon, and cellulose derivative fibers such as
acetate fibers), regenerated protein fibers, acrylic fibers, polyolefin fibers,
polyurethane fibers, and vinyl fibers, but excluding nylon and polyester
fibers; and blends thereof.
The present invention comprises applications of the products of an
adaptation of technology used in the electroless plating of plastics,
particularly printed circuit boards made of plastic, with metals. See, for
example, Encyclopedia of Polymer Science and Engineering (Jacqueline
I. Kroschwitz, editor), Wiley and Sons, 1987, vol. DC, pp 580 - 598. As
applied to textiles, this process includes two steps. The first step is the
activation of the textile by precipitating catalytic noble metal nucleation
sites on the textile. This is done by first soaking the textile in a solution
of a low-oxidation-state reductant cation, and then soaking the textile in a
solution of noble metal cations, preferably a solution of Pd + + cations,
most preferably an acidic PdCl 2 solution. The low-oxidation-state cation
reduces the noble metal cations to the noble metals themselves, while
being oxidized to a higher oxidation state. Preferably, the reductant cation
is one that is soluble in both the initial low oxidation state and the final
high oxidation state, for example Sn ++ , which is oxidized to Sn + ++ + , or
Ti +++ , which is oxidized to Ti ++ ++ .
The second step is the reduction, in close proximity to the activated
textile, of a metal cation whose reduction is catalyzed by a noble metal.
Examples of such cations include Cu 4" " , Ag + , Zn + ÷ and Ni +÷ . The
reducing agents used to reduce the cations typically are molecular species,
for example, formaldehyde in the case of Cu + + , and hydrazine hydrate in
the case of Ag J"r+ . Because the reducing agents are oxidized, the metal
cations are termed "oxidant cations" herein. After these oxidant cations
are plated on the textile, the metal plating may be processed further, for
example, by oxidation to the oxide. This oxidation is most conveniently
effected simply by exposing the metallized textile to air. The metallized
textiles and the oxide-plated textiles thus produced are characterized in that
their metal or metal oxide plating is bonded directly to the textile fibers.
The plating may cover substantially all of the fiber surfaces, or may cover
only part of the surfaces.
As bactericides and fungicides, the metallized textiles thus produced
have a variety of applications. They may be used to make garments, such
as socks, which inhibit infections such as athletes foot and jock itch. They
may be used to make intrinsically antiseptic bandages. They may be used
in interior furnishings, such as floor coverings including carpets, wall
coverings, curtains, and upholstered furniture: in hospitals, where they
inhibit the spread of nosocomial infections, and as interior furnishings
generally in warm, humid climates to inhibit mildew. They may be
incorporated in food storage containers to lengthen the shelf life of the
food stored therein.
Because the metallized textiles thus produced conduct electricity,
they have a variety of electrical applications that exploit their flexibility
and relatively light weight compared to fabrics woven from pure metals.
They may be used as electrodes in applications, such as medical
applications, in which flexibility, to match the contours of a patient's
body, is an advantage. Similarly, they may be used as electrodes in
lightweight batteries. They may be used as anti-static devices: for
example, in carpets, to prevent static buildup in rooms where electronic
devices sensitive to static, such as computers, are used; or in automotive
upholstery, as taught by Hatomoto et al. in U.S. Patent No. 5,009,946.
They may be used as radio frequency shields to prevent eavesdropping on
cordless telephone conversations or on stray electronic signals generally.
In this application, they are aesthetically more pleasing than the metallic
screens conventionally used for this purpose. They may be used in radar-
reflective camouflage nets.
Finally, the textiles thus produced may be used as fire retardants,
for example in fire barriers, garments, and public transportation vehicles.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is of applications of metallized textiles
produced by binding a full or partial metallic plating to a textile.
Specifically, the various applications that comprise the present invention
employ textiles with metal and metal oxide coatings intimately and
permanently bonded to the fibers of those textiles.
The process of plating a textile with a metal or metal oxide for use
in the applications of the present invention may be better understood with
reference to the following Examples. These Examples are illustrative, and
should not be construed to restrict the scope of the present invention in any
way.
EXAMPLE 1
A dilute acidic solution of SnCl 2 was prepared by dissolving SnCl 2
and concentrated HC1 in water.
An dilute acidic solution of PdCl 2 was prepared by dissolving PdCl 2
and concentrated HC1, and water.
An 8" x 3" cotton swatch was activated as follows:
Soak in a bath of the SnCl 2 solution.
Soak in a bath of the PdCl 2 solution.
A dilute basic CuS0 4 solution was prepared by dissolving CuS0 4
and NaOH (in appro-ximately equal weight proportions), a chelating agent,
and polyethylene glycol in water.
The activated cotton swatch and formaldehyde were added to the
CuS0 solution under a pure oxygen atmosphere. After between 2
minutes and 10 minutes, the cotton swatch was removed.
The palladium deposited on the cotton swatch in the activation step
catalyzed the reduction of the Cu ++ by the formaldehyde, providing a
layer of copper tightly and intimately bonded to the fibers of the cotton
swatch. The swatch, which initially was white in color, now was the color
of copper metal, while retaining the flexibility and physical characteristics
of the original fabric. The metallic copper color remained unchanged after
several launderings.
EXAMPLE 2
An 8" x 3" cotton swatch was activated as in Example 1. A dilute
solution of AgN0 3 was prepared by dissolving AgN0 3 , concentrated
NH 4 OH, and glacial acetic acid in water. The volume ratio of
concentrated NH 4 OH to glacial acetic acid was about 1.7 to 1.
The activated cotton swatch, and dilute aqueous hydrazine hydrate,
were added to the AgN0 3 solution. After 10 minutes, the cotton swatch
was removed.
The palladium deposited on the cotton swatch in the activation step
catalyzed the reduction of the Ag + by the hydrazine hydrate, providing a
partially oxidized layer of silver tightly and intimately bonded to the fibers
of the cotton swatch. The swatch, which initially was white in color, now
was dark gray. The dark gray color remained unchanged after several
launderings.
While the invention has been described with respect to a limited
number of embodiments, it will be appreciated that many variations,
modifications and other applications of the invention may be made.