US3660138A - Metallized article - Google Patents

Abstract

Fibrous article with heat-and-light reflecting quality provided by a metal coating. The metal coating is overcoated with a mixed resin system. The article thus produced has enhanced stability of the fibrous substrate due to the heat and light protection provided by the coatings and also has enhanced strength due to the coatings consistent with substantially retaining hand and softness of the fibrous article. The metal coating is uniquely abrasion and mar resistant, water repellent and launderable and dry cleanable consistent with high moisture vapor transmission of the article (breathability).

Description

United States Patent Gorrell '[54] METALLIZED ARTICLE [72] Inventor: John H. Gorrell, Billerica, Mass.

[73] Assignee: King Seeley Thermos Co., Ann Arbor,

Mich.

[22] Filed: Feb. 5, 1969 211 App]. No.: 796,930

[52] U.S.Cl. ..117/35 V, 117/71 R, 117/107, 117/132 A, 117/132 BE, 1l7/l35.1, 1l7/l38.8 N, 117/154, 117/160 R, 117/161 KP, 117/161ZA,

204/192 511 1111. C1. ..B44d 1/12, 134411 1/02 58 Field ofSearch ..117/132 A, 132 BE, 76, 35 R,

117/35 V, 135.1, 138.8 N, 161 KP, 161 ZA, 71, 154; 161/64; 28/75; 204/192 [56] References Cited UNITED STATES PATENTS 2,930,105 3/l960 Budd ..117/71 x 14 1 May 2, 1972 3,244,544 4/1966 Scharf..... ..117/71 X 2,689,802 9/1954 Korver.... ..117/35 3,063,872 11/1962 Bo1debuck.. 17/71 X 3,230,289 1/1966 Eder et 31.... ...117/132 X 3,355,348 11/1967 Laman ..117/76 P X Primary ExaminerEdward G. Whitby Attorney-Harness, Dickey & Pierce [57 ABSTRACT 2 Claims, No Drawings METALLIZED ARTICLE This invention relates to fibrous articles e.g. fabric (woven or bonded), paper and fiber (filament or yarn) to be formed into fabric or paper and particularly to fibrous articles coated with metal to provide heat and light reflectance for decorative and'functional (insulation) purposes.

The principal known fabric or fiber metallizing methods are (1) application of metal flakes in a plastic matrix, e.g. U.S. Pat. Nos. 2,630,620; 2,767,104 and 3,220,871 embodied in Miliurn (registered trademark of Deering Milliken Company) and (2) vacuum metallizing of a fabric or fiber, e.g. British Pat. Nos. 663,251; 721,879; 800,093; 816,906; and US. Pat. Nos.2,9l2,345; 2,921,864; 2,907,678 and German Pat. No. 1,182,631 embodied in Metalon and lnsalune (registered trademarks) fabrics (see Man Made Textiles Magazine (Jan. 1965) 43 and Textile World- (May 1965) 1 l3). I

Both of these processes have significant limitations in regard to abrasion and mar resistance and launderability of the metal coating.

It is the object of the invention to provide improved metallized fibrous articles characterized by improved abrasion and mat resistance, corrosion resistance, launderability, dry cleanability and water repellence consistent with high moisture vapor transmission (breathability) of the articles.

It is a further object of the invention to provide enhanced strength and stability of the articles consistent with the foregoing object.

It is a further object of the invention to provide substantially unimpaired hand and softness of the treated fibrous article consistent with the foregoing objects. 7

It is a further object of the invention to provide very high heat and light reflectance consistent with the foregoing objects. 1

It is a further object of the invention to provide an economical method of manufacturing such an article with a single step post coating following metallizing.

In general the improved fibrous article is made by metallizing a fibrous article in a vacuum chamber, removing the article from the vacuum chamber. and dipping it into a mixed resin solution to form an overcoat resin layer over the metal layer.

The metallizing may be practiced on a filament or yarn later formed into a fabric or directly on a woven or bonded fabric or paper. The fiber involved may be natural or synthetic or a mixture as in cotton-polyester woven fabrics. Metal may be applied directly to the fiber or the fiber-may be pre-coated prior to the application of metal to reduce outgassing from the fiber in the metallizing vacuum chamber and to enhance adhesion of metal to fiber substrate.

Preferably the metal is applied to a thickness of about inches but may be as thin as 10 or as thick as 10 inches. The metal forms a continuous layer along at least one side of the fibrous article but without bridging gaps or openings in the article, to leave the breathability of the article unhindered. The continuity of the film provides a better reflectance than a flake coating or a similar metallized film which simulates a flake coating due to crocking or crazing or removal of intermittent portions thereof due to abrasion or laundering or the like.

The overcoat is a mixed r'esin system of high adhesion to the metal and low cohesion within itself. The overcoat is applied with a carrier of organic solvent or water which is driven ofi by heating to efi'ect cure of the mixed resin system. The resultant product is found to have a higher moisture vapor transmission with the overcoat than without it (where fibers are metallized,

the moisture vapor transmission can only be evaluated after.

subsequently forming into a fabric). The overcoat is selected to provide a high transparency to infrared radiation in the range of visible to near infrared wavelength (including 8-9 microns) so that reflectance of the article to such radiation with the overcoat is at least 90 percent of reflectance without it.

In a first and preferred embodiment of the invention, the overcoat is made of a mixed polyurethane-silicone resin system with organic solvent carrier. ln other embodiments, mixed polyacrylic-silicone resin systems with water carrier are used. The urethane-silicone coating is designed primarily for outdoor application with the constituents selected for ultraviolet stability, fungus and mold resistance, resistance to weather and humidity extremes as well as water repellency and the other objects stated above. The water based acrylicsilicone coatings are the most readily adaptable to the paddertenter applicator arrangements common in the textile industry and more adaptable to aerosol spraying for consumer use (and less flammable than the organic system), but afi'ord water repellency to a lesser degree. 7

The mixed resin system perform overlapping functions. The first resin in the coating a film forming polymer, e.g. acrylic (including methacrylic etc.) or the urethane provides an adherent protective layer for the metal. Among acrylics,

melamine cross linked acrylic acid polymers are preferred (e.g. Union Carbide LKSB 0200). The film is very thin to afford high reflectance of radiation by the article as a whole. The second resin is a mixture of silicones including typically, the conventional water repellent polydimethyl siloxane marketed as Dow Cornings DC-200 or General Electric s SF-96 solutions or Dow Corning DC-36 emulsion. Also included are a mar resistant silicone (e.g. Dow Corning DC-l 1) and a coupling agent (e.g. Dow Corning DC-600). The film forming polymer alone would bridge over and block moisture vapor in the absence of the silicones. The silicones alone would not adhere well to metal. g

The practice of the invention will be best understood from the following nonlimiting examples:

EXAMPLE 1 (05158-38) a. 74 parts (by volume) of solvent (70 toluene; 14 Cellosolve) mixed with 8 parts of polyurethane solution 25 percent solids in xylene solvent) and matic agitation.

b. a 10 percent solution of polyvinyl butyral inalcohol was mixed with solvent (3 parts PVB, 1 solvent). The solvent was 1 percent glyoxal in Cellosolve. The glyoxal per se was 40 percent solids in water. 7 1

cJModified silicones were similarly mixed (1 part SF-96, 1 part DC-600, 1.5 part DC-l 1) Before mixing the SF-96 was reduced to 1 percent intoluol, the DC-600 to 1 percent in Cellosolve, the DC-l l to 0.5 percent in Cellosolve.

d. The three components (a) (b) (c) were mixed. Then 0.1 parts of Dow Corning F-l-l522 (glycol modified polydimethylsiloxane) was added to 100 parts of the mixture and this was mixed.

v e. Swatches of Dacron (trademark) polyester fabric and ripstop nylon fabric were placed in a vacuum metallizing chamber and aluminum was evaporated in the chamber under vacuum and condensed on the fabric substrates to a decora-- lost metal in some cases, retained it in others. Both nylon and polyester fabrics with metal and resin overcoat retained their metal coating with repeated washings.

- Radiation reflectance of the fabrics was measured with a spectrophotometer in the wavelength range from visible light to 2.5 microns (near infrared). Averages of measured values were mixed rapidly with pneu- Percent Percent reflec transtanec mission 'lnnr'lullizr-ll polyester 17 84 Al -tallizwl lightweight polyester (with and Without ovvrcoulr 35 51 lulllll'll light to nn-dium polyester 79 11 ['nnn-Iullizc-(l nylon ripstop... 23 64 Alt-Inllimvl nylon ripstop..... 85 l'nnn-Inllizml nylon sailcloth 41 .\lvl.nlli7.vtl nylon suilcloth 87 EXAMPLE 2 (4048-4 SERIES) A variation of the Example 1 coating was prepared as follows:

urethane (TO-I) l2 parts toluene 73 pans modified SI -96" parts modified DC-600 s 5 parts modified DC-l 1" 5 parts 'Turco Guard division of Purex Chemicals Co. (25% solids in xylene). "General Electric dimethyl siloxane reduced to 2% in toluene.

"Dow Corning DC-600 silicone reduced to 4% in butyl Cellosolve. "Dow Corning DC-ll silicone reduced to 1% in Cellosolve.

Ripstop nylon was vacuum metallized to decorative grade thickness and overcoated with the above resin mixture by immersion, pressing between rollers and suspending in an oven to heat to about 250 F for 5 minutes and in some cases for 30 minutes. i

-The fabrics were home laundered as in Example 1. Uncoated (no resin) fabrics lost their metal completely in one washing. Fabrics having the overcoat retained substantially all their metal. Best retention of metaland metal luster was in a -as the home laundering. The nonresin coated swatches had lost all metal. But the overcoated samples retained it (entirely for laundering and stoddard solvent, but with some blushing for perchloroethylene solvent).

EXAMPLE 3 Nylon and polyester fabrics metallized and overcoated as in Example 1 were made into bags and filled with water with l to 2 inches head and suspended in air. These bags held the water several weeks without dripping. The bags were also exposed to spilled coffee and no stain resulting. Similar bags made of metallized fabric without overcoating would not hold water. Measurements were made of moisture vapor transmission and it was found that the metallized and overcoated. fabrics had.

higher transmission than the fabrics, as uncoated, or coated with metal alone.

EXAMPLE 4 (12028) I d. Mix (c) with 1 part sodium silicate- 3H O c. Mix (b) with 1 part diluted acetic acid percent in e. Filter (d) through sheer Dacron and let stand. Cure at 350 F for 3 minutes. The. pre-coated cotton was aluminized to decorative grade thickness and topcoated as in Example 1. It exhibited excellent resistance to laundering at 104 F water and cold water detergent withno apparentmetal loss.

EXAMPLE 5 In variations of the Example 4 experiment it was observed that standing for a week enhanced the adhesion of metal coating and topcoat. It was also observed that the base coat as applied to cotton and other natural and synthetic fabrics gave the metal coat a' substantial resistance to laundering even without topcoat.

However the above topcoat improved the resistance to laundering and is also necessary for'abrasion resistance and corrosion resistance in outdoor use.

EXAMPLE 6 A top coat was prepared as follows:

a. Mix 10 parts acrylic (0200) solution (55 with 73 parts water b. Mix (a) with 10 parts DC-600 silicone (reduced to 20 percent in Cellosolve) c. Mix 5 parts DC-l l silicone (1 percent in Cellosolve) with -d. Mix 2 parts DC-36 silicone with (c).

A metallized ripstop nylon was immersed in it, squeezed and dried at 300 F for 3 minutes. Upon laundering it held most of percent solids) its metal, but with some dulling, while a similar metallized v fabric without topcoat lost its'me'tal in laundering. The fabric hand was similar with and without top coat.

- EXAMPLE 7 50 parts of the Example 6 topcoat buffered with a small addition of NH; C1 to 8 ph, were mixed with 50 parts distilled water and 90 parts of the mixture was mixed with 2 parts DC-37 silicone. Metallized triacetate fabric was topcoated with this mixture and dried at 300 F for 15 minutes. The resultant fabric laundered with onlyslight metal loss, exhibited a bright luster and good hand was breathable.

EXAMPLE 8 EXAMPLE 9 The following modified acrylic-water base formulation was found to give the best protection to Tyvek and Reemay fabrics consistent with good hand:

y parts distilled water I a 3 parts Rhoplex K-87 self-cross-linking acrylic 1 part DC-36 silicone I t 2.5 parts Acetic acid (4 percent in water) 5 parts NH; Cl 10 percent in water) 2 parts xylene I 0.5 parts DC-l 00 1 percent in Cellosolve) 0.5 parts DC-ll (1 percent in Cellosolve) 0.5 parts Dow Corning F-1-522 glycol modified dimethylpolysiloxane.

Three compositions of the invention are now stated with total solvent'and/or water stated separately and on a weight of vliquid component basis (expressed as approximate percent of COMPOSITION A Component Quantity (1%) Solids Amine cross linked acrylic l 1% 55 DC-36 hydrophobic silicone 2 35 SF% hydrophobic silicone 2 100 (50 Centistokes) DC-600 coupling silicone .2 63 DC-l 1 mar resist silicone .04 Cellosolve 23 0 Distilled Water 62 0 COMPOSITION B Component Quantity Solids Self cross link acrylic emulsion 3.2% 46 DC-36 l 35 DC-600 .000045 63 DC-l l .000045 10 Dow Corning F-l-l522 .4 100 Cellosolve .85 0 Xylene 875 0 Ammonium Chloride .025 100 Glacial Acetic Acid 1.15 0 Distilled Water 92.5 0

COMPOSITION C Component Quantity Solids Polyurethane 9.7% 25 DC-600 .01 63 DC-l l .0] I0 Fll522 .l 100 SF-96 .0] I00 Polyvinyl butyral .3 I00 glyoxol L8 40 Cellosolve l8 0 isopropyl alcohol 2.3 0 toluol 68 0 The scope of the invention includes various other metals copper, zinc, tin, gold, silver, bright platinum, bronze, Woods metal and equivalent metals of which can be applied to fibrous article substrates as thin films to afford bright reflectance. The

coating may also be deliberately absorbent such as a platinum black coating. The coating may also be in sub-layers for providing iridescent effects, but such sub-layers would add up to a single thin deposited layer, in contrast to the three dimensional structure of Milium coatings which have overlapping and nonparallel metal flakes in a plastic matrix. The metal layers of the present invention are essentially continuous in local zones, but are, of course, discontinuous to the extent the fabric is discontinuous in the openness of its weave for moisture vapor transmission and may be made further discontinuous by application of the metal in a screen pattern or the like for decorative effects.

The method of application of the metal(s) may be vacuum evaporation, sputtering, pyrolytic or chemical vapor deposition, or electroless or any method which provides a suffrciently thin metal coat which is continuous to the extent indicated and also not bridge over an open fabric weave.

The film forming resin has as a basic criterion that it must be I capable of reacting and cross-linking with the hydrophobic component (silicone) when cured. The film forming polymer resin used in the topcoat may be acrylic, acetal, ester, phenolic, ethers and epoxies, vinyls and urethane base polymers including copolymers thereof. The key criteria is a film forming capability without excessive use of plasticizers and avoidance of stiffening the fabric substrate. Cohesiveness of the resin is limited by the combination with the hydrophobic silicone of the topcoat and enhanced adhesion is obtained to the metal in metal coated fabric areas and to the fabric in fabric areas uncoated with metal. Coupling of several of the water repellent topcoats of the present invention to fiber surface is not a surprising result. Coupling to substantially continuous metal surface to the degree indicated herein and consistent with the objects of the invention is unique.

The finished fibrous article (whether treated as a fabric or treated as a fiber and then formed to a fabric or paper) may be used for clothing, draperies, clothing linings, tentage, outdoor boat and car covers, umbrellas, sleeping bags and the like. In connection with use near engines, the article has enhanced resistance to gasoline or oil attack.

The combination of metal and topcoat protects the substrate (e.g. nylon fiber) from actinic decay due to ultraviolet and infrared radiation. The principal protection in this regard is provided by the metal while the topcoat protects the metal from attack by dust, bacteria, chemicals and water exposure ofoutdoor use as well as in laundering and dry cleaning.

The metal coat also affords static resistance to the article.

The finished article also has enhanced strength which is particularly noticeable for sheer fabrics and paper. The strength of Kleenex tissues was doubled when metallized and topcoated as set forth herein.

The metal is normally applied to one side of a fabric or fiber but may be applied to both sides. The topcoat is applied to both sides.

The essential features of the topcoat system are (a) a film forming polymer resin adherent to the metal which may be in polymer form as mixed or after curing, and (b a hydrophobic (including mar resistant) silicone of known composition R SiO(4-n)/2 where R is selected from the group consisting of hydrogen, alkyl, aryl, aralkyl, cycloaliphatic, or alkenyl radicals and n is from 1.0 to 2.9. Water in amounts which may be small are necessary to enhance silicone polymerization in accordance with known practice for use of these compositions and (c) carrier.

The solids" coating of the initial mixture composition (including liquid form components of [00 percent solids" composition) is from 1 to l0 percent of the total topcoat composition, the balance being carrier water and/or solvents essentially all removed during curing.

The component (a) is 50 98 percent of the solids content and the component (b) is 250 percent of the solids content. The component (b) includes a major portion of a hydrophobic silicone (including mar resistant) or mixture of such compositions and a minor portion (l to 50 percent) of a coupling agent effective to couple to the hydrophobic silicone and the component (a). It is optional whether the coupling agent or agents are also capable of coupling effectively to the metal and/or fabric. The coupling agent is not necessarily hydrophobic, per se. The Dow Corning handbook entitled Silane Coupling Agents" (published 1967) gives a particularly good analysis of coupling agents for various film forming polymers. While the handbook analysis is not in terms of coupling the polymer to another silicone component, it has been determined by my experiments that the selections stated in the book are adequate for this purpose to the extent necessary in protecting metallized fabrics.

The silicones now widely used or useful as conventional water repellent fabric finishes all serve to varying degrees the purpose of reducing the web forming tendency of the components (a). Preferred choices have been indicated above.

What is claimed is:

1. A fibrous article comprising a fiber substrate having at least two sides and coated with a metallic layer on at least one side, the metallic layer being overcoated with a layer of mixed resins adhering to the metal, the metal coating having a thickness between 10" and 10 inches and being essentially in a single layer along the coated side of the fiber and the resin coating including a resin which forms a film and a component which is hydrophobic and cross-linked with the film forming resin, the mixed resin layer being sufficiently thin and trans- .parent to radiation in the region of visible to near infra red wavelengths to preserve a reflectance of the article to said radiation which is at least percent of the reflectance with percent by weight of an adherent film forming resin and 2-50 percent .by weight of a resin'modifying component comprising at least one polysiloxane substituted with substituents selected from the group consisting of hydrogen, alkyl, aryl, aralkyl, cycloaliphatic or alkenyl radicals.

' UNITED STATES PATENT OFFICE CERTIFICATE OF GORRECTION Patent No. 660,138 Dated Mav 2, 197Z Inventor(s) John H. Gorrell It is certified that error appears in the above-identified patent and that: said Letters Patent: are hereby corrected as shown below:

Column 5, C I O IVIPOSITION A, heading after Quantity delete the numeral 1 such as to read Column 5, line 11, COMPOSITION A, '0" should be moved to the left such as to align with above numbers.

Column 5, COMPOSITION B, line 24, change "'875" to read as --.,8'75*--e Signed and sealed this 19th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Paten

Claims (1)

1. 2. The article of claim 1 wherein the mixed resins as a coating mixture comprises 1-10 percent by weight of included solids in liquid dispersed form, the solids comprising 50-90 percent by weight of an adherent film forming resin and 2-50 percent by weight of a resin modifying component comprising at least one polysiloxane substituted with substituents selected from the group consisting of hydrogen, alkyl, aryl, aralkyl, cycloaliphatic or alkenyl radicals.