# Patent

## Title
One-way viewable screen

## Abstract

A screen or fencing structure which provides one-way viewing characteristics under conditions of substantially equal lighting on each side of the structure is described. The structure has a fabric which has a light transmission of about 2.8% to about 25%. The first side of the structure has an overall light reflectance to light transmission ratio of greater or equal to about 2.5, and the opposite side of the structure has an overall light reflectance to light transmission ratio of less than or equal to about 2. Fabrics that can be used to make screens are also described.

## Background
BACKGROUND OF THE INVENTION
Fencing is often utilized in a variety of situations to define property boundaries, or to keep people, animals, and or objects inside or out of a property. Conventional fencing is generally provided in two forms: two-way viewable (where individuals on each side of the fencing can see through it) or non-viewable (where individuals on each side of the fencing cannot see through it, as in the case of privacy fencing.)
Similarly, screen and divider panels are conventionally provided to be non-viewable, to block individuals on either side of the screen from seeing clearly through to the other side. In some circumstances, one-way viewable screens or mirrors have been provided. In particular, one-way mirrors are occasionally provided in some department stores, nurseries, and witness questioning rooms so that the activities taking place inside the room can be observed from others outside that room, without the people in the room being observed being able to see their observers. One way see-through mirrors only work when the light condition on one side is substantially greater than the other. As will be readily appreciated, such one-way glass mirrors are rigid and fragile, rendering them useful only in specific environments such as along a rigid wall.
Other one-way viewable materials such as perforated vinyls, are designed for situations where the lighting conditions on the two sides of the material are quite different. (For example, such materials are typically used on building windows or automobile windows, where the light inside of the structure and adjacent to one side of the material would be dramatically different from that on the outside of the structure, adjacent to the other side of the material.) Those panel materials typically have a see through open area of about 30 to 50% comprising a plurality of relatively large openings (e.g. circular openings about 1 mm in diameter.) However, they do not provide proper one-way see through properties when lighting conditions on both sides are about the same.
Examples of such perforated vinyl, printed film and semitransparent metallic coatings on glass used to provide one-way see through (from a low light intensity side, and non-see through from high light intensity side) are described in U.S. Pat. Nos. 5,925,437, 6,258,429 and 4,673,609. As noted previously, such materials do not provide one-way viewing when the lighting on both sides of the material is approximately the same.
SUMMARY
The present invention is directed to a fence, screen, divider or the like which provides one-way viewing properties in situations where light conditions on both sides of the structure are approximately the same. (As used herein, such structures will be collectively referred to as “screens”.) As noted previously, prior one-way viewing structures do not enable one-way viewing when the lighting is approximately the same on both sides of the structure. In fact, the present inventors have found that the conventional materials have an optical pathway equivalent to at least about 30-50% light transmission (e.g., 1 mm diameter holes spaced by 1.4 mm were found to be equivalent to about 40% light transmission; 1/16 inch diameter holes spaced by 3/32 inch were found to be equivalent to about 35% light transmission, by calculating the percent open area and assuming transmission occurs only through that open area.) However, it has been found that such high levels of light transmission fail to provide the non-see through property in one direction in equal lighting situations regardless of how reflective the material is. Preferably, the area of the openings in the screen of the invention are smaller than the area of a 1 mm diameter circular opening (i.e. 0.785 mm2. Openings of less than 0.2 mm2 are preferred (the area of a 0.55 mm diameter circle), and openings 0.07 mm2 (the area of a 0.3 mm diameter circle) are even more preferred. However, other sizes and shapes of openings can be used within the scope of the invention.
In addition to the advantage of providing one-way viewing under similar lighting conditions on both structure sides, the invention can also be made to have good air permeability and high mechanical strength, in most cases, without the need for a perforation manufacturing step. Because of these additional properties, it has been found that the material has particular utility in outdoor fencing applications, where high winds may be encountered.
The screens are designed for optimal performance when the light intensity is greater than 20 Lux. As noted, the screens of the invention work well when the light intensity on both sides of the screen is approximately the same. However, the screens also have been found to work well when the light intensity on the reflective side is greater than the light intensity on the highly light absorbing (i.e. less reflective) side. It is to be noted that a range of light transmission values and light reflection to light transmission ratios are described; as will be readily appreciated, the see-through and blocking performance are affected by the light intensity. For example, a greater see through capability is generally achieved when the light intensity is brighter than when it is relatively low.
The screens of the invention desirably have a light transmission of about 2.8 to about 25% in the 400-700 nm spectrum (i.e. the visible spectrum.) The screens also have a first side having an overall light reflectance to light transmission ratio of ≧2.5, and a second side having an overall light reflectance to light transmission ratio of ≦2.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a screen according to the invention;
FIG. 2 is a photomicrograph of a woven version of a structure according to the invention;
FIG. 3 is a photomicrograph of a knit version of a structure according to the invention, illustrating an alternative distribution and size of openings;
FIG. 4 is a schematic representation of a screen in FIG. 1, illustrating the light transmission, reflectance and absorption;
FIG. 5 is a cross-sectional view of an alternative embodiment of the invention; and
FIG. 6 is a cross-sectional view of a tufted version of a fabric of the invention; and
FIG. 7 is a cross-sectional view of a woven fabric according to the invention.



DETAILED DESCRIPTION
In the following detailed description of the invention, specific preferred embodiments of the invention are described to enable a full and complete understanding of the invention. It will be recognized that it is not intended to limit the invention to the particular preferred embodiment described, and although specific terms are employed in describing the invention, such terms are used in a descriptive sense for the purpose of illustration and not for the purpose of limitation.
With reference to the drawings, FIG. 1 is a perspective representative of a screen 10 according to the invention, which in this case is in the form of a fence. As illustrated, the fence includes supports 16, to which a material is secured by way of fasteners 18. (As will be readily appreciated by those of ordinary skill in the art, the screen can be constructed in any configuration or manner, with FIG. 1 simply being generally representative of how a material can be oriented such that it is exposed to substantially the same light on each of its two sides.) The screen 10 includes a first side 12 designed to be the non-see-through side, and a second side 14 designed to be the side that can be seen through. When this screen is utilized under conditions of approximately equal lighting on each side, an observer looking at side 12 of the screen would not be able to see through the screen, while an observer looking at side 14 would be able to see through the screen.
As will be appreciated by those of ordinary skill in the art, an observer looking at a structure such as a screen can only see things on the opposite side of the screen by virtue of the light that is transmitted through the screen from the opposite side. As shown in FIG. 4, each side of the material F is exposed to substantially the same amount of light; therefore:

T1=T2, and T2+R2+A2=100%, and T1+R1+A1=100%, where

    
    
        T1=the light transmitted through side 12
        R1=the light reflected by side 12;
        A1=the light absorbed by side 12;
        T2=the light transmitted through side 14;
        R2=the light reflected by side 14;
    
    


A2=the light absorbed by side 14, since the amount of light is all either transmitted through the screen, reflected back from the screen, or absorbed by the screen.
The inventors have discovered that by engineering the fabric to have a light transmission of about 2.8% to about 25% in the 400-700 nm spectrum, and engineering the first side of the screen to have an overall light reflectance to light transmission ratio of ≧2.5 and the second side of the screen to have an overall light reflectance to light transmission ration of ≦2, a screen can be achieved that has good non-see through (i.e. blocking) characteristics on one side, and good see through characteristics on the other side, under conditions where each side is exposed to substantially the same amount of light.
The invention is characterized by a textile structure having a light transmission of about 2.8-about 25% in the 400-700 nm spectrum. (For purposes of this application, light transmission within the visible spectrum is obtained by measuring the light transmission at every 10 nm wavelength from 400-700 nm using a spectrometer in a conventional manner, with light transmission and reflection being measured as a percentage of an incident light beam.) Even more preferably, the structure has a light transmission of about 15% or less in the 400-700 nm spectrum. In addition, the textile has two sides with substantially different optical properties, where one side of the textile has an overall light reflectance to light transmission ratio of at least 2.5, and preferably about 5 or greater, and more preferably about 10 or greater, and the other side of the textile has the ratio of about 2 or less, and more preferably about 1.5 or less. It is also highly preferred that the side with high reflectance have minimal light absorption while the other side has the maximum light absorption possible. (As noted previously, the total light is the sum of the light transmitted through the fabric plus the light reflected back by the fabric and the amount of light absorbed by the fabric. Therefore it follows that to maximize reflection, one would seek to minimize absorption.)
In addition to having a light transmission of about 2.8-25%, the size of openings in the material is also desirably small (as noted previously), with the openings being relatively uniformly distributed across the whole material. It has found that this combination provides particularly good see-through properties. When larger sized holes are used in combination with the above-described low level of overall opening, fewer holes are needed and the holes would be separated farther apart. As a result, it was discovered that an observer would not be able to piece together the whole picture on the other side of the material from limited partial light transmission regardless of other optical properties the material may have. The size of opening therefore for this invention is preferably 0.7 mm2 or less, and more preferably 0.07 mm2 or less, and the openings are desirably substantially uniformly distributed across dimension of the material designed to be see-through. In most cases, it would be desirable to have the entire dimension of the structure be see through, in which case the openings would be distributed across the entire dimension of the material. However, in another of the invention; see-through portions of material could be provided adjacent areas that are not see through. For example, a grid structure formed of regions without openings could be formed to provide additional strength to the material, provide a particular design, or the like.
The overall light transmission of about 2.8-25% through the textile structure is preferably achieved by controlling the yarn density such that the openings between yarn interstices of the fabric structure provide the desired level of light transmission. The textile can be of any variety, including woven, knit, or nonwoven. In a preferred form of the invention designed to perform well in environments where high strength is desired, a warp knit structure is preferred. Alternatively, perforation, coating and printing can also be used to generate optical pathways or partially block optical pathways to control the level of light transmission. However, because perforation generates waste material, and can significantly reduce the strength of the material, it would generally not be preferred for applications where high mechanical strength is required (e.g. for fence and barrier materials.)
Light reflection can be achieved using one or more of the following: a white fiber/fabric surface; a coating on the fabric containing reflective materials such as titanium dioxide, zinc oxide, zirconium oxide, barium sulfate, calcium carbonate, magnesium carbonate, calcium phosphate, mica, metal pigments such as baluminum and brass; a metallic coating, such as sputtering or thermal vapor deposition of aluminum on a textile structure, or electroless plating of silver, chromium or similar reflective metals. Fibers with trilobal cross-sections or ribbon like fibers can also be used to provide high reflection.
Optical brighteners, other types of luminescent dyes and pigments can also be incorporated on the highly reflective side of the fabric to provide improved reflectance. Those materials can absorb UV light energy and emit the energy as visible light, and thus provide improved brightness to a human's eyes.
Low reflectance is achieved by dark color fabric surface, either by dyeing, printing or coating with materials having high light absorption property. High light absorption can be achieved by using one or more of: dark color dyes, and/or pigments such as carbon black, iron oxide, and graphite.
In one embodiment, the inventive textile structure is provided by forming a textile structure using a warp knitting process, dyeing the fabric to a dark black color, and coating one side of the fabric with a reflective coating such as a mixture of polyacrylic resin and titanium dioxide pigment. The warp knit process provides sufficient yarn density such that the light transmission through the structure is 25% or less, the coating provides high overall reflectance on one fabric side, and the black dye provides the high light absorption on the opposite surface. Alternatively, the fabric could be formed from previously-dyed or solution dyed fibers, or be coated with a coating without being first dyed.
In another embodiment, a white or other light colored fabric is stitched, laminated, or otherwise secured to a dark-colored highly light absorbent fabric to form a two layer composite, such that the overall composite has a light transmission of 25% or less in the visible wavelength range, and reflectance to transmission ratio of at least 2.5 on the white fabric side and a ratio of about 2 or less on the dark colored fabric side. Fabric construction techniques can utilized to form such textile structure with minimal or no further processing. For example, a reflective white or light colored yarn and a dark colored highly light absorbent yarn, for example, can be woven or knit into a fabric such that the light colored/white yarn is disposed predominantly on one side, while the dark colored yarn is disposed predominantly on the other side. The fabric would desirably be formed with a yarn density such that the overall light transmission through the finished fabric is less than about 25%. Alternatively, satin weave, dobby weave, jacquard weave, plain weave, basket weave, or the like can be used to weave a single layer or double layer fabric wherein a light colored yarn is predominantly disposed on one side of fabric and a highly light absorbing dark colored yarn is predominantly disposed on the other side. For example, a white trilobal yarn can be used as a warp yarn and a solution dyed dark black yarn can be used as a filling yarn in a satin weave such that the white warp yarn is predominantly disposed on one side and the dark black yarn on the other. As a further alternative, a knit fabric with a highly reflective side and a highly light absorbing side can also be formed by using warp knit, and double needle bar knitting. A double layer fabric is preferred when weaving or knitting technique is used to dispose reflective yarn on one side and light absorbing yarn on the other.
In yet another example which is illustrated in FIG. 5, a pile fabric is formed, where the pile yarn is a reflective light colored yarn, and the base yarn on the other side of the fabric is dark colored with high light absorbing property. As shown in FIG. 5, the fabric, shown generally at 20, includes a ground yarn structure 22, and a pile formed from a plurality of fiber tufts 24. The pile texture on one side thus provide high overall light reflective feature, while the base of the fabric would have openings (between the yarns in the ground structure and the tufts) to facilitate see through the side of the fabric adjacent the ground yarn structure. The “cone” type of cross section (with the “cones” being formed between adjacent pile tufts) of such fabric structure is desirable for enhancing one way see through. In addition, light absorbing coatings or the like could be provided on the ground yarn 22 and the portion of tuft yarn in contact with the ground yarn.
FIG. 6 illustrates the fabric shown in FIG. 5, with an opening O depicted, which would be present between the yarns forming the fabric. Similarly, FIG. 7 illustrates a woven fabric, with an opening O illustrated as it would appear between the adjacent yarns forming the fabric, and showing the different sides 12, 14 (as shown in FIGS. 1 and 4.)
In yet another embodiment, a pattern of print and/or texture is further provided on top of the highly reflective side. Such texture or print on a reflective surface would attract an observer to visually focus on the plane of such surface and omit the light transmit through the fabric. Such pattern can significantly improve the non-see through property on the highly reflective side. Such pattern can be provided by printing, fabric construction, embossing, etching or the like. Photoluminescent or similar bright color print would be suitable for this purpose. Dark color print on highly reflective side, on the other hand, would diminish the reflectance and would not be desirable. Screening printing, ink jet printing, air brush, flexographic printing, electrostatic printing, and laser printing can be used to provide a printed pattern. Texture pattern can by formed by jacquard weaving, double needle bar knitting, dobby weaving, patterned sanding, laser etching, embossing and similar methods.
Light transmission and reflectance of such textile structure can be measured using a light spectrometer, such as a Jasco V-570 spectrometer available from Jasco, Inc. of Easton, Md., using an incident light of visible wavelength from 400 nm to 700 nm.
Other features such as infrared signature, infrared absorption, reflection, and infrared fluorescence can also be incorporated to one or both side of the fabric by using infrared reflective pigment, carbon black or infrared absorbing/fluorescence dyes. In addition, designs can be printed, embossed, painted, or otherwise provided on one or both of the fabric surfaces as desired, provided the pattern does not interfere to an extent that the respective reflectance, transmission and absorbance cannot be achieved.
EXAMPLE
Example 1
A plain warp knit fabric having 24 courses by 28 wales per inch was formed by using 3 bars of 1/150/24 56T (meaning a 1 ply, 150 denier yarn with 24 filaments per yarn of Dacron type 56 round cross-section polyester yarn) yarns and one bar of 1/100/34 56T background yarn. The fabric had a weight of about 8.88 ounces per square yard. The intersticial openings of the fabric varied mostly in the range of 0.1-0.25 mm, and they are spaced from each other by about 0.3-2 mm as shown in FIG. 3. The fabric was then jet dyed in a conventional manner to a dark black color using black disperse dye such that a low reflectance (approximately 4%) in the visible spectrum is achieved. The fabric was then heat set in a conventional manner on a tenter frame. An aluminum reflective pigment-containing metallic finish spray paint manufactured by Rust-Oleum Corporation was used to spray paint one side of the fabric such that the side was covered with metallic paint. The coated fabric has an air permeability of about 135 cfm at 125 Pa pressure using ASTM D737-96. The fabric was fixed vertically in both indoor and outdoor locations such that both sides of the fabric were under similar illumination conditions. Observation was made from 10 to 20 feet away from the fabric from both sides to determine the one-way see through property. The fabric provided good see-through property from the uncoated black side, but substantially non-see through property from the coated side when both side of the fabric was under equal lighting conditions either indoor or outdoor.
Example 2
The same warp knit fabric as used in Example 1 was instead dyed with off-white cream color using disperse dyes. The fabric was then heat set in a conventional manner on a tenter frame. One side of the fabric was then spray painted with metallic reflective coating using metallic finish spray paint manufactured by Rust-Oleum Corporation (of the same variety used in Ex. 1), while the other side of the fabric was coated with a dark black semi-flat spray paint of the variety manufactured sold under the tradename Krylon by Sherwin-Williams, inc. The coated fabric exhibited substantial non-see through from the metallic coating side and good see-through from the black coating side under equal light condition on both side of the fabric both indoor and outdoors when tested in the same manner as described in respect to Example 1.
Example 3
The same off-white cream colored warp knit fabric from Example 2 was used. One side of the fabric was coated with a dark black semi-flat Krylon spray paint. The black coating side provides highly light absorbing and good see through property. Interestingly, no reflective treatment is needed on the other side where off-white fabric surface is reflective enough to provide non-see through property.
Example 4
A woven fabric was formed using a single 574 denier polyester monofilament warp yarn and 535 denier single monofilament Nylon 6 filing yarn. The fabric is woven in a plain weave pattern with 34 picks per inch and 35 ends per inch. A black coating was applied by using semi-flat Krylon black spray paint on one side. The other side is coating with a 1:1 ratio mixture of Mearlite Ultra bright UWA (manufactured by Engelhard Corporation) and a polyurethane latex, Impranil 85UD (by Bayer Corp, leverkusen, Germany). Mearlite Ultra Bright UWA is a water dispersion of titanium dioxide coated mica reflective pigment. It was found that this fabric did not have good non-see through properties from the reflective side, which it is believed by the inventors was due to the high level of openness. Due to the relative high openness of the fabric structure, the resulting fabric does not have good non-see through property from the highly reflective side of the fabric although significantly less clear see through was observed from the reflective side. This can also be understood from the low 2.37 ratio of reflection to transmission on the reflective side.
Example 5
A black activated carbon woven fabric, FM1/250 (manufactured by Activated Charcoal International, in United Kingdom), was coated with a metallic finish spray paint manufactured by Rust-Oleum Corporation on one side only. The black activated carbon fiber provided highly light absorbing property on the other side. The interstitices between warp and filing yarns provide the light transmission property. The coated fabric has good one way see through property in both indoor and outdoor lighting condition. The interstitial opening of the fabric had openings of about 0.2-0.35 mm (across the dimension of the rectangular holes), and are spaced about 0.8-1 mm apart.
Example 6
A woven spun polyester fabric having 204 denier spun warp yarn and 12 denier spun filing yarn, with a plain weave pattern at 55 picks per inch and 68 ends per inch was dyed dark black using black disperse dye. One side of the fabric is then coated with metallic finish spray paint manufactured by Rust-Oleum Corporation. The fabric exhibited see through property only under outdoor high intensity lighting conditions. The spun yarn texture and too low level of light transmission made the fabric not suitable for one-way see through uses under low light intensity.
Light transmission and reflection measurement is made using a Jasco V-570 visible/UV/NIR spectrometer. Only visible light transmission and reflection are made. The results are listed in the following tables. It was found that the Examples which exhibited a light transmission of about 2.8% and about 25%, and a first side having an overall light reflectance to light transmission ration of ≧2.5, and a second side having an overall light reflectance to light transmission of ≦2 performed well at enabling see through from only one fabric side when the both fabric sides were exposed to the same light conditions. Example #4 illustrates an upper limit of light transmission for non-see through from the reflective side, and Example #6 illustrates a lower limit of light transmission needed for see through from the light absorbing side.
Example 1
Results















Wavelength

Reflection
Reflection
Ratio - A
Ratio - B


nm
Transmission, %
on side A, %
on side B, %
side
side







700
3.881
31.692
9.772
8.165936614
2.517907756


690
3.695
32.161
8.144
8.703924222
2.20405954


680
3.454
31.774
6.622
9.199189346
1.917197452


670
3.242
31.35
5.396
9.669956817
1.664404688


660
3.122
31.241
4.663
10.00672646
1.49359385


650
3.043
31.167
4.226
10.2421952
1.388761091


640
3.002
31.147
4.003
10.37541639
1.33344437


630
2.987
31.159
3.916
10.43153666
1.311014396


620
2.982
31.19
3.906
10.45942321
1.309859155


610
2.984
31.231
3.926
10.46615282
1.315683646


600
2.983
31.264
3.94
10.4807241
1.320817968


590
2.984
31.3
3.961
10.48927614
1.327412869


580
2.986
31.329
3.992
10.49196249
1.336905559


570
2.983
31.358
3.997
10.512236
1.339926249


560
2.977
31.371
3.969
10.53778972
1.333221364


550
2.973
31.391
3.962
10.55869492
1.332660612


540
2.972
31.408
3.97
10.5679677
1.335800808


530
2.967
31.422
3.951
10.59049545
1.331648129


520
2.954
31.404
3.917
10.6310088
1.325998646


510
2.952
31.429
3.926
10.64668022
1.329945799


500
2.951
31.459
3.949
10.66045408
1.338190444


490
2.946
31.477
3.953
10.68465716
1.341819416


480
2.938
31.495
3.956
10.71987747
1.346494214


470
2.94
31.556
3.974
10.73333333
1.35170068


460
2.956
31.747
4.002
10.73985115
1.353856563


450
2.967
31.905
4.032
10.75328615
1.358948433


440
2.949
31.785
4.025
10.77822991
1.364869447


430
2.924
31.684
3.998
10.83584131
1.367305062


420
2.921
31.761
4.04
10.87333105
1.383087984


410
2.913
31.714
4.112
10.88705802
1.411603158


400
2.919
31.797
4.25
10.89311408
1.455978075


Average
3.046677419
31.48929032
4.466129032
10.3802041
1.446584433









Example 2
Results















Wavelength

Reflection
Reflection




nm
Transmission, %
on side A, %
on side B, %
Ratio - A
Ratio - B







700
3.021
32.772
3.579
10.84806356
1.184707051


690
3.108
33.54
3.666
10.79150579
1.17953668


680
3.1
33.656
3.636
10.85677419
1.172903226


670
3.066
33.576
3.592
10.95107632
1.171559035


660
3.061
33.66
3.591
10.9964064
1.173146031


650
3.053
33.747
3.59
11.05371765
1.175892565


640
3.046
33.826
3.591
11.10505581
1.178923178


630
3.04
33.905
3.591
11.15296053
1.18125


620
3.037
33.981
3.592
11.1890023
1.182746131


610
3.032
34.053
3.593
11.23120053
1.185026385


600
3.027
34.126
3.595
11.27386852
1.187644533


590
3.02
34.183
3.598
11.31887417
1.191390728


580
3.015
34.243
3.6
11.35754561
1.194029851


570
3.01
34.287
3.601
11.3910299
1.196345515


560
3.002
34.335
3.606
11.43737508
1.201199201


550
2.996
34.384
3.61
11.47663551
1.20493992


540
2.992
34.432
3.614
11.50802139
1.207887701


530
2.987
34.473
3.619
11.54101105
1.211583529


520
2.974
34.485
3.624
11.59549428
1.218560861


510
2.971
34.529
3.633
11.62201279
1.222820599


500
2.962
34.571
3.643
11.67150574
1.229912221


490
2.955
34.593
3.655
11.70659898
1.236886633


480
2.946
34.612
3.667
11.74881195
1.244738629


470
2.941
34.652
3.687
11.78238694
1.253655219


460
2.951
34.857
3.722
11.81192816
1.261267367


450
2.965
35.115
3.747
11.84317032
1.263743676


440
2.945
35.117
3.742
11.92427844
1.270628183


430
2.92
35.01
3.749
11.98972603
1.28390411


420
2.915
35.106
3.777
12.0432247
1.295711835


410
2.896
35.119
3.78
12.12672652
1.305248619


400
2.881
35.15
3.809
12.20062478
1.322110378


Average
2.994677419
34.32564516
3.648354839
11.46924561
1.219029019









Example 3
Results















Wavelength

Reflection
Reflection




nm
Transmission, %
on side A, %
on side B, %
Ratio - A
Ratio - B







700
4.642
42.569
3.574
9.170400689
0.769926756


690
4.715
43.54
3.649
9.234358431
0.773913043


680
4.681
43.756
3.606
9.347575304
0.770348216


670
4.623
43.592
3.568
9.429374865
0.771793208


660
4.605
43.679
3.564
9.485124864
0.773941368


650
4.586
43.769
3.557
9.5440471
0.775621457


640
4.568
43.855
3.553
9.600481611
0.777802102


630
4.55
43.945
3.549
9.658241758
0.78


620
4.531
44.044
3.547
9.720591481
0.782829397


610
4.512
44.138
3.543
9.782358156
0.785239362


600
4.491
44.265
3.541
9.856379426
0.788465821


590
4.475
44.387
3.539
9.918882682
0.790837989


580
4.456
44.47
3.538
9.979802513
0.793985637


570
4.432
44.492
3.535
10.03880866
0.797608303


560
4.404
44.512
3.532
10.1071753
0.801998183


550
4.386
44.596
3.532
10.16780666
0.805289558


540
4.364
44.723
3.534
10.24816682
0.809807516


530
4.342
44.823
3.536
10.32312298
0.814371257


520
4.314
44.87
3.536
10.40101994
0.819656931


510
4.289
45.017
3.54
10.49591979
0.825367218


500
4.267
45.149
3.546
10.58097024
0.831028826


490
4.239
45.193
3.553
10.66124086
0.83816938


480
4.209
45.207
3.561
10.74055595
0.846044191


470
4.182
45.276
3.577
10.82639885
0.855332377


460
4.17
45.594
3.608
10.93381295
0.865227818


450
4.159
46.009
3.629
11.06251503
0.872565521


440
4.115
46.07
3.616
11.19562576
0.87873633


430
4.062
45.956
3.62
11.3136386
0.891186608


420
4.034
46.051
3.642
11.41571641
0.902825979


410
3.967
45.844
3.64
11.5563398
0.917569952


400
3.909
45.411
3.655
11.61703761
0.935021745


Average
4.36383871
44.67103226
3.571612903
10.27140294
0.820726195









Example 4
Results















Wavelength

Reflection
Reflection




nm
Transmission, %
on side A, %
on side B, %
Ratio - A
Ratio - B







700
27.302
65.82
16.763
2.410812395
0.613984323


690
26.998
65.826
16.559
2.438180606
0.613341729


680
26.893
65.706
16.359
2.443238017
0.608299558


670
26.836
65.349
16.046
2.43512446
0.597928156


660
26.76
65.081
15.766
2.432025411
0.58916293


650
26.651
64.791
15.462
2.431090766
0.580165847


640
26.52
64.494
15.09
2.431900452
0.569004525


630
26.399
64.133
14.639
2.429372325
0.554528581


620
26.268
63.727
14.087
2.426031674
0.536279884


610
26.113
63.34
13.524
2.425611764
0.51790296


600
25.994
62.939
13.077
2.421289528
0.503077633


590
25.914
62.617
12.827
2.416338659
0.494983407


580
25.887
62.286
12.697
2.406072546
0.490477846


570
25.838
61.926
12.563
2.396702531
0.486221844


560
25.787
61 .556
12.423
2.387094272
0.481754372


550
25.726
61.258
12.336
2.3811708
0.479514888


540
25.681
60.981
12.304
2.374557066
0.479109069


530
25.666
60.735
12.338
2.366360165
0.480713785


520
25.626
60.464
12.365
2.359478654
0.489517755


510
25.6
60.23
12.365
2.352734375
0.483007813


500
25.558
59.927
12.311
2.344745285
0.481688708


490
25.515
59.627
12.203
2.336939055
0.478267686


480
25.473
59.35
12.078
2.329917952
0.474149099


470
25.403
59.058
11.958
2.324843522
0.470731803


460
25.251
58.787
11.865
2.328105818
0.469882381


450
25.079
58.416
11.791
2.329279477
0.470154312


440
25.037
57.878
11.675
2.311698686
0.466309861


430
25.035
57.385
11.603
2.292190933
0.46347114


420
24.994
56.855
11.513
2.274745939
0.460630551


410
24.903
55.985
11.389
2.248122716
0.457334458


400
24.738
54.299
11.082
2.194963214
0.447974776


Average
25.85306452
61.31696774
13.19541935
2.370346421
0.509115216









Example 5
Results















Wavelength

Reflection
Reflection




nm
Transmission, %
on side A, %
on side B, %
Ratio - A
Ratio - B







700
3.734
34.063
3.167
9.122388859
0.848152116


690
3.688
34.209
3.148
9.275759219
0.853579176


680
3.67
34.423
3.164
9.379564033
0.862125341


670
3.68
34.469
3.147
9.366576087
0.855163043


660
3.681
34.548
3.128
9.385493073
0.849769084


650
3.687
34.617
3.117
9.388934093
0.845402766


640
3.689
34.689
3.106
9.403361345
0.841962591


630
3.687
34.759
3.088
9.42744779
0.837537293


620
3.697
34.811
3.07
9.416012984
0.830403029


610
3.702
34.851
3.055
9.414100486
0.825229606


600
3.706
34.919
3.037
9.422288181
0.819481921


590
3.71
34.967
3.032
9.425067385
0.817250674


580
3.71
35.015
3.013
9.438005391
0.81212938


570
3.714
35.054
3.001
9.438341411
0.808023694


560
3.716
35.065
2.985
9.436221744
0.8032831


550
3.718
35.109
2.971
9.442980097
0.79908553


540
3.723
35.135
2.956
9.437281762
0.793983347


530
3.723
35.161
2.941
9.444265377
0.789954338


520
3.727
35.175
2.923
9.437885699
0.784276898


510
3.725
35.197
2.909
9.44885906
0.780939597


500
3.731
35.213
2.894
9.437952292
0.775663361


490
3.733
35.233
2.878
9.438253415
0.770961693


480
3.737
35.247
2.863
9.431897244
0.766122558


470
3.736
35.255
2.85
9.436563169
0.762847966


460
3.712
35.287
2.833
9.506196121
0.763200431


450
3.682
35.382
2.827
9.609451385
0.767789245


440
3.691
35.429
2.83
9.598753725
0.766729884


430
3.698
35.422
2.813
9.578691184
0.760681449


420
3.71
35.489
2.812
9.565768194
0.757951482


410
3.698
35.538
2.809
9.610059492
0.759599784


400
3.69
35.558
2.79
9.636314363
0.756097561


Average
3.706612903
35.00932258
2.972806452
9.445184989
0.802108966









Example 6
Results















Wavelength

Reflection
Reflection




nm
Transmission, %
on side A, %
on side B, %
Ratio - A
Ratio - B







700
6.178
22.784
14.835
3.687924895
2.401262545


690
5.042
21.683
10.542
4.300476002
2.090836969


680
4.048
20.521
7.163
5.069416996
1.76951581


670
3.313
19.535
4.984
5.896468458
1.504376698


660
2.863
18.911
3.828
6.605309116
1.337059029


650
2.623
18.523
3.279
7.061761342
1.250095311


640
2.507
18.355
3.027
7.321499801
1.207419226


630
2.455
18.289
2.922
7.449694501
1.190224033


620
2.436
18.295
2.891
7.510262726
1.186781609


610
2.432
18.329
2.894
7.536595395
1.189967105


600
2.434
18.363
2.906
7.544371405
1.193919474


590
2.433
18.395
2.919
7.560624743
1.199753391


580
2.445
18.439
2.945
7.541513292
1.204498978


570
2.449
18.472
2.975
7.542670478
1.214781543


560
2.456
18.511
2.998
7.537052117
1.220684039


550
2.465
18.542
3.024
7.522109533
1.226774848


540
2.48
18.6
3.075
7.5
1.239919355


530
2.511
18.671
3.157
7.435682995
1.257268021


520
2.557
18.792
3.272
7.349237388
1.27982456


510
2.609
18.919
3.437
7.251437332
1.317362974


500
2.685
19.093
3.65
7.110986965
1.359404097


490
2.758
19.247
3.866
6.978607687
1.401740392


480
2.752
19.271
3.898
7.002543605
1.416424419


470
2.653
19.119
3.668
7.206558613
1.382585752


460
2.57
18.989
3.465
7.388715953
1.348249027


450
2.533
18.957
3.377
7.484011054
1.333201737


440
2.501
18.904
3.332
7.558576569
1.332267093


430
2.521
18.952
3.422
7.517651726
1.357397858


420
2.584
19.177
3.645
7.421439628
1.410603715


410
2.686
19.373
3.957
7.212583768
1.473194341


400
2.853
19.718
4.51
6.911321416
1.580792149


Average
2.833290323
19.08803226
4.124612903
7.00055179
1.383160842









As noted previously, it was discovered by the inventors that a screen having a light transmission of about 2.8-about 25% at the 400-700 nm spectrum, and a first side having an overall light reflectance to light transmission ratio of ≧2.5, and a second fabric side having an overall light reflectance to light transmission ratio of ≦2 provided good see-through from one side and good blockage (i.e. non-see through properties) from the opposite side.
This textile structure can be used in a variety of end uses including but not limited to fences, barriers at building and road construction sites, to cordon off accident sites, as a security curtain or wall panel, room divider, or the like.
In the specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purpose of limitation, the scope of the invention being defined in the claims.

## Claims

1. A screen having one-way viewing properties when both sides are exposed to approximately the same intensity of light comprising: a knit or woven fabric having light transmission of about 3 to about 15% in the 400-700 nm spectrum and having first and second fabric sides, the first fabric side including a reflective material containing coating and having an overall light reflectance to light transmission ratio of ≧5, and the second fabric side including a dark colored dye or a dark colored pigment and having an overall light reflectance to light transmission ratio of ≦1.5, wherein the fabric includes a plurality of openings, said openings being ≦0.2 mm2 in size, wherein the second fabric side has a light absorption of greater than about 80%.

2. A screen according to claim 1, wherein the first fabric side has a light absorption of about 60% or less.

3. A screen according to claim 1, wherein the plurality of openings in the fabric are ≦0.07 mm2 in size.

4. A screen according to claim 1, wherein the plurality of openings are generally evenly distributed across the fabric.