WO2006020397A1

WO2006020397A1 - Garment comprising a spunbonded nonwoven high visibility fabric and safety vest comprising such a fabric of polyester filaments

Info

Publication number: WO2006020397A1
Application number: PCT/US2005/026660
Authority: WO
Inventors: Imad Mohammed Qashou
Original assignee: Reemay, Inc.
Priority date: 2004-08-04
Filing date: 2005-07-28
Publication date: 2006-02-23
Also published as: US20060026731A1

Abstract

The invention is a high visibility safety garment comprising a spunbonded nonwoven fabric colored with a fluorescent dye or pigment. The spunbonded nonwoven fabric in some embodiments may comprise continuous filaments of polyester that are thermally bonded together. Safety garments (10) prepared in accordance with the invention are lightweight, flexible, and meet the requirements of ANSI 107-1999 for luminance, chromaticity, colorfastness, and durability. The safety garment in some embodiments may be in the form of a vest having multiple stripes of retroreflective material (40).

Description

GARMENT COMPRISING A SPUNBONDED NONWOVEN HIGH

VISIBILITY FABRIC AND SAFETY VEST COMPRISING SUCH A

FABRIC OF POLYESTER FILAMENTS

BACKGROUND OF THE INVENTION

The invention relates generally to high visibility garments, and more particularly to high visibility safety vests that meet the American National Standard Institute (ANSI) 107-1999 standard.

Outdoor workers along roadways, construction sites, airport tarmacs, intersections and the like face many dangers. In many cases, automobiles and tractor trailers may speed pass, often within inches of workers. Inattentive drivers also pose a significant problem as they swerve in and out of traffic lanes. Visibility may be limited for drivers of heavy equipment and trucks, while noise may make it difficult for workers to hear approaching vehicles and equipment.

Even the most attentive driver may pose a risk to workers. In many circumstances workers on foot may not always be easily visible to approaching motorists. Outside work is routinely performed at night or when light levels are low such as dawn, dusk, or during inclement weather. Visibility problems result in many deaths and injuries that occur when outside workers are struck by vehicles or other mobile equipment.

High- visibility apparel may be worn to help prevent workers from being struck by vehicles or other equipment operated by someone who otherwise may not be able to see them during the day or at night. High visibility apparel significantly increases the visibility of workers. The use of florescent and/or retroreflective materials improves visibility under day and night conditions. The International Safety Equipment Association (ISEA) has developed the American National Standard for High- Visibility Safety Apparel (ANSI/ISEA) to ensure that high visibility apparel meets minimum safety standards. The current standard, ANSI 107-1999, establishes a set of performance criteria for high- visibility apparel. The standard defines three garment classifications, which are based on worker hazards and tasks, complexity of the work environment or background, and vehicular traffic and speed.

Under the current standard, high visibility safety apparel is made of a background material having a fluorescent color that emits optical radiation at wavelengths longer than is absorbed. Depending upon the particular classification, the safety apparel will also include varying stripes of retroreflective material that are disposed on the background material.

The majority of high visibility safety apparel is made from woven or knit substrates that typically have a basis weight from 204 to 340 grams per square meter (gsm). Garments prepared from these substrates can be heavy and uncomfortable for the wearer. U.S. Patent No. 5,478,628 describes a high visibility fabric comprising a non- woven web and a binder having a fluorescent pigment. The binder is applied to the nonwoven web and is then driven to the surface with a drying means to produce a two sided coloring effect wherein the majority of the fluorescent pigment is present at one surface, and the opposite surface has a pale appearance. The use of a binder can result in a fabric that is heavier, stiffer, and more difficult to manipulate.

Thus, there still exists a need for safety apparel that is lightweight, flexible and meets ANSI 107- 1999 standards.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a fabric for producing high visibility safety garments that meet current ANSI standards for luminance, chromaticity, dimensional stability, and colorfastness, while still being lightweight, flexible, and easy to manipulate.

The fabric comprises a spunbond nonwoven web that has been colored with a high visibility fluorescent dye or pigment. The spunbonded nonwoven may comprise a variety of different thermoplastic polymers, such as polyester, that are capable of being melt spun to form continuous filaments. Dyeing processes that use high temperatures and high pressures are particularly useful because the fluorescent color dye is incorporated throughout the fabric resulting in better colorfastness, luminance, and chromaticity. In an alternate embodiment, the filaments of the spuribonded nonwoven web may be extruded with a fluorescent pigment incorporated therein so that the pigment is incorporated into the structure of the fibers. Using a dye or pigment to color the fabric eliminates the need to have a binder for binding the color to the fabric. Additionally, colored layer is not limited to an exterior layer that comprises the binder and the fluorescent pigment. As a result, safety garments can be produced that are lightweight, flexible, and meet ANSI 107-1999 requirements for chromaticity, durability, luminance, and colorfastness. The fabric can be used to prepare a variety of different safety garments, hi one embodiment, the high visibility safety garment is in the form of a vest. The safety vest may include multiple reflective stripes that comprise a retroreflective material. The placement and quantity of reflective stripe may be varied depending upon the desired classification. Thus, the present invention provides a high visibility fabric that is useful preparing safety garments that are lightweight, durable, and meet the requirements of ANSI 107-1999 for durability, chromaticity, luminance, and colorfastness.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

Figure 1 is a graphical illustration of an individual wearing a high visibility safety vest that is in accordance with the invention;

Figures 2a and 2b are front and back views of a high visibility safety vest that is in accordance with the invention;

Figure 3 is a chromaticity diagram for a high visibility yellow fabric that is in accordance with the invention; and

Figure 4 is a chromaticity diagram for a high visibility orange fabric that is in accordance with the invention. DETAILED DESCRIPTION OF THE INVENTION The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

With reference to FIGS. 1 and 2, a high visibility safety garment in accordance with the invention is illustrated and broadly designated as reference number 10. FIG. 1 illustrates the safety garment that is configured in the form of a vest being worn by an individual 12. The safety garment is not limited to any particular form and may also be in the form of a jacket, bib, shirt, waistcoat, poncho, coverall, and the like.

The vest 10 comprises a fabric 30 having multiple stripes of reflective material 40 disposed on its surface. The fabric is typically a colored fluorescent fabric that is highly conspicuous and emits optical radiation at wavelengths longer than those absorbed. The fluorescent fabric enhances daytime visibility, especially at dawn or dusk, and is typically red, red-orange, or lime-yellow in color. The reflective stripes 40 typically comprise a retroreflective material that reflects a high percentage light in the direction from which it came.

The safety garment 10 is configured as a vest having a front side 30a and a back side 30b. The front side 30a comprises right and left front panels 14, 16, respectively that may come together at front edges 14a, 16a and are connected to the backside 30b. As shown in FIG. 1, the front edges 14a, 16a in some embodiments may define a chest opening 11 and neck opening 26 (see FIG. 2a). Shoulders 22, 24 extend over the shoulder of the wearer, and together with front panels define a neck opening 26. The vest also includes arm openings 18, 20 along the sides of the vest. The vest may be formed from individual pieces of fabric that are cut and sewn together to form the garment, or may be cut from a single piece of fabric having a seam at the shoulders or the sides. The seams may be prepared from heat sealing or sewing the pieces of fabric together. In some embodiments the safety garment may include a hem that extends around peripheral edges of the fabric. The hem may be prepared from stitching or heat sealing the fabric.

The vest has a plurality of highly reflective safety stripes 40 that reflect light in the direction of its source. As shown, the vest comprises a first reflective stripe 40a and a second reflective stripe 40b that extend horizontally about the vest so that they encircle the torso of the wearer. The vest may also include left and right reflective stripes 40c, 4Od that generally extend vertically from the front panels, over the shoulders, and to the backside 30b. It should be recognized that the position, size, and quantity of reflective stripes can be varied depending upon the particular standard and classification.

In some embodiments the vest may also include suitable means for fastening the front panels together. Such means include, without limitation, zippers, Velcro, buttons, straps, ties, and the like that may be used to releasably attach the front panels together. The background material comprises a high visibility fabric prepared from a spunbonded nonwoven web that has been colored with a fluorescent dye or pigment. The fabric is particularly useful for preparing safety garments that are highly visible and meet ANSI 107-1999 standards for chromaticity, luminance, colorfastness, and durability. The spunbond nonwovens used in the present invention are made from continuous polymeric filaments that are bonded together. Generally, spunbond nonwoven fabrics are prepared by extruding a thermoplastic polymer through a large number of fine spinneret orifices to form a multiplicity of continuous filaments, and the filaments of molten polymer are solidified and then drawn or attenuated, typically by high velocity air, and then randomly deposited on a collection surface. The filaments are then bonded to give the web coherency and strength. Common bonding methods that may be used include, for example, thermal bonding, chemical bonding with a resin or adhesive, thru-air bonding, sonic bonding, hydroentangling, and the like. Area bonding and point bonding are two common techniques for thermal bonding the web. Area bonding typically involves passing the web through a heated calender composed of two smooth steel rollers or passing heated steam, air or other gas through the web to cause the filaments to become softened and fuse to one another. As a result, the fabric is bonded throughout its area where the filaments intersect one another. Point bonding consists of using a heated calender nip to produce numerous separate and discrete point bond sites. The point bonding calender nip is comprised of two nip rolls, wherein at least one of the rolls has a surface with a patterned of protrusions. Typically, one of the heated rolls is a patterned roll and the cooperating roll has a smooth surface. As the web moves through the calender roll, the individual filaments are thermally bonded together at discrete locations or bond sites where the filaments contact the protrusions of the patterned roll. Preferably, the calender rolls are engraved with a pattern that produces point bonds over about 10 to 40 percent of the area of web surface, and more preferably about 20 to 30 percent.

For the present invention, area bonding either with heated calender rolls or by passing a heated stream of fluid through the web is the preferred bonding process because it coheres the filaments together at points of intersection to produce a fabric that is quite strong and abrasion resistant. Area bonding imparts considerable strength to the fabric while retaining the integrity of the fibrous structure on both surfaces. Point bonding is also a very useful method of bonding the web because it bonds the filaments together in small, discrete, and closely spaced areas of the web to produce a fabric that is also quite strong and abrasion resistant.

Spunbonded nonwoven fabrics can be prepared from a variety of different thermoplastic polymers that are capable of being melt spun to form filaments. Examples of polymers that can be used to form the spunbonded nonwoven fabric include, without limitation, polyester, polyamide, polyolefins such as polypropylene, polyethylene, and olefin copolymers, or other thermoplastic polymers, copolymers and blends. These polymers may also be used in any combination or shape to from bicomponent or tricomponent filaments.

A particularly useful spunbond nonwoven fabric is comprised of polyester filaments, and more particularly is formed from polyester homopolymer filaments. A variety of additives can be used with the hompolymer including, but not limited to, optical brighteners, delusterants, opacifiers, colorants, antistats, and other common melt additives. A fibrous binder may also be included within the spunbond nonwoven fabric during the manufacturing process as continuous binder filaments in an amount effective to induce an adequate level of bonding. The binder is typically present in an amount ranging from about 2 to 20 weight percent, such as an amount of about 10 weight percent. The binder filaments are generally formed from a polymer composition exhibiting a melting or softening temperature at least about 10° C lower than the homopolymer continuous filaments. Exemplary binder filaments may be formed from one or more lower melting polymers or copolymers, such as polyester copolymers. In one advantageous embodiment of the invention, the spunbond layer is produced by extruding polyester homopolymer matrix filaments (polyethylene terephthalate) interspersed with binder filaments formed from a lower melting polyester copolymer, such as polyethylene isophthalate. Typically, the homopolymer filaments constitute the matrix fiber and the copolymer filaments have a lower melting point and constitute a binder filament. Generally, as the web passes through the heated calender rolls or a stream of heated fluid, the filaments are bonded together at points of intersection. The portions of the binder filaments that are heated are melted or rendered tacky while in contact with the heat calender roll or stream of heated fluid, and as a result, the binder and matrix fibers are bonded to together to form a strong coherent fabric.

Suitable spunbond nonwoven fabrics should have a machine direction tensile strength typically of about 11,000 grams per inch and at least 10,000 grams per inch. The spunbonded nonwoven fabrics should also typically have a basis weight of from about 50 to 150 grams per square meter (gsm), and more desirably from about 75 to 125 gsm. The fabric typically has a machine direction elongation from about 20 to 40 percent, and somewhat more typically about 25 percent. The fabric typically has a Frasier porosity of at least 185 cubic feet of air per minute per square foot of fabric at a pressure differential of 0.5 inches of water.

In some embodiments, the safety garments prepared from spunbonded nonwovens may have an unfinished hem. Spunbonded nonwovens comprise a web of continuous filaments containing numerous bonds resulting in a strong and coherent fabric. As a result, safety garments may be prepared from the spunbonded fabric that do not require a hem to keep the edges of the fabric from unraveling. The fabrics may be used to prepare safety garments more efficiently and with reduced labor.

The spunbonded nonwoven fabric includes a colored fluorescent material that may be incorporated into the fabric as a dye, or as a pigment that is extruded with the polymeric filaments. The fluorescent material is typically red, red-orange, or lime-yellow in color, hi one embodiment, the fluorescent color may be applied to the web using dyeing techniques. The fabric may be dyed using a variety of different techniques including, but not limited to jig dyeing, beam dying, jet dyeing and the like. Dyeing techniques, such as jet dyeing, that involve using high temperatures and pressures to force the dye into the fabric are particularly useful because the resulting colored fabric will meet the durability requirements of ANSI 107-1999. As a result, the fluorescent fabrics can meet the minimum washing, weather resistance, chemical resistance, UV stability, and leeching requirements. Suitable dyes include, for example, Dianix^® Luminous yellow 1OG and Dianix^® Luminous red G, which are available from DyeStar L.P.

Dyeing the fabric eliminates the need to have a binder for bonding the fluorescent color to the fabric. As a result, high visibility fabrics of the invention have a lighter basis weight and are therefore lighter, more comfortable to the wearer, easily storeable, and more flexible with respect to the movements of the wearer. Additionally, the colored fabric should have better drape and softness, and should be easier to process and manufacture. hi an alternative embodiment, the fluorescent color may be added as a pigment during the extrusion process. For example, polypropylene filaments may be coextruded with a fluorescent pigment to produce a fluorescent nonwoven fabric.

The reflective stripes comprise a retroreflective material. A retroreflective material, in contrast to a mirror, returns a high percentage of light or other radiation back in the direction from which it came regardless of the angle of incidence. A retroreflective material is able to reflect light through a wide range of entrance angles. As a result, the retroreflective material can be used to reflect light from a vehicle headlight back to the vehicle. Suitable retroreflective materials should meet the minimum standards for the coefficient of retrorefiection that is specified in Tables in the current ANSI 107-1999 standard. There are a variety of different types of retroreflective materials that may be used in the practice of the invention. An exemplary retroreflective material includes, but is not limited to, Scotchlite™ reflective material, which is available from 3M. The reflective stripes may be attached to the background material in a wide variety of ways including, but not limited to, heat lamination, adhesive bonding, sewing, and the like.

For class 1, 2, and 3 garments, the minimum requirements for the area of visible background material and retroreflective material is specified in Tables 1, 5, and 6 of the publication American National Standard for High- Visibility Safety Apparel, ANSI 107-1999 (the "107-1999 publication") published by The Safety Equipment Association and approved Jun. 1, 1999 by the American National Standards Institute, Inc., which tables are incorporated herein by reference.

With reference to the Figures, it should be recognized the vest 10 has been constructed to comply with visibility standards according to current ANSI

Standards. Safety garments prepared in accordance with the invention may be modified to comply with some other visibility standard, such as an international standard or revised ANSI standard. The standards may be revised in the future and as such, the invention is not limited to any particular current standard. The current ANSI 107-1999 standard specifies various requirements for chromaticity, luminance, colorfastness, and durability. These requirements are set forth in various tables and charts that are included in the 107-1999 publication. As discussed in the examples below, fabrics prepared in accordance with the invention meet these requirements.

EXAMPLES

The current ANSI 107-1999 standard specifies various requirements for chromaticity and durability. Tables 1 through 4 summarize durability tests that were performed on high visibility fabrics that are in accordance with the invention.

As required by ANSI 107-1999, the tests were conducted by a third party certifier according to standard tests created by the American Association of Textile

Chemists and Colorists (AATCC). Tables 1 and 2 include data from tests performed on a nonwoven spunbonded polyester fabric that has been colored with a high visibility yellow dye. Tables 3 and 4 include data from tests performed on a nonwoven spunbonded polyester fabric that has been colored with a high visibility orange dye.

Table 1: Dimensional Change of Fabric (High Visibility Yellow)

Test: AATCC 135 (3)IIIA(iii)

Fabric was machine washed at 105° F; permanent press cycle; tumble dry permanent press cycle.

Table 2: Colorfastness of fabric (High Visibility Yellow)

Table 2: Continued

Table 2 continued

Drypressing at l50° C.

*Kev to AATCC Gray Scale Ratings

Class 5 — Negligible or no color alteration Class 4 — Slight color alteration Class 3 — Noticeable color alteration Class 2 — Considerable color alteration Class 1 - Much color alteration

Table 3: Dimensional Change of Fabric (High Visibility Orange)

Test: AATCC 135 (3)IIIA(iii)

Table 4: Colorfastness of fabric (High Visibility Orange)

Table 4 continued

Table 4 continued

Dry pressing at l50° C.

*Kev to AATCC Gray Scale Ratings

Class 5 - Negligible or no color alteration Class 4 - Slight color alteration Class 3 - Noticeable color alteration Class 2 - Considerable color alteration Class 1 - Much color alteration

ANSI 107-1999 specifies that the background material have a chromaticity falling within an area defined in Table 2 of the 107-1999 publication, and a minimum luminance factor that is also defined in Table 2. With reference to FIGS. 4 and 5, chromaticity diagrams for the high visibility orange and yellow diagrams are illustrated. As shown in the FIGS, both the high visibility orange and yellow fabrics have a chromaticity that is within the required chromaticity area that is defined in ANSI 107-1999. The area is represented by the four-sided box shown in the Figures. Tables 5 and 6 include chromaticity and luminance data for the samples that was provided by a third party certifier.

Table 5: Chromaticity and luminance determination for High Visibility Yellow Fabric

**AATCC 16E

Table 6: Chromaticity and luminance determination for High Visibility Orange Fabric

**AATCC 16E AFU (AATCC Fading Unit)

During the chromaticity test the fabric samples were exposed to a specific amount of exposure made under conditions that are specified in the AATCC test methods. An AFU is 1/20 of the light-on exposure that is required to produce a color change that is equal to step 4 on the AATCC Gray Scale. Although not specifically mentioned in ANSI 107-1999, the fabric needs opacity to pass the luminance and chromaticity requirements. Under ANSI test procedures, two layers of the background material are tested against a black background. The material will not meet ANSI standards if the background material can be seen through the material. As a result, to pass the luminance and chromaticity the background material must have a certain level of opacity. High visibility fabrics prepared in accordance with the invention have the necessary level of opacity. As should be apparent from the data contained in the above tables, the high visibility fabrics of the invention meet the chromaticity, luminance, dimensional stability, and colorfastness requirements of ANSI 107-1999.

Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

THAT WHICH IS CLAIMED:

1. A high visibility safety garment comprising a flexible high visibility fabric having portions configured for covering the back and chest of a wearer, a neck opening and arm openings, said flexible high visibility fabric comprising a spunbond nonwoven fabric formed of substantially continuous filaments, said filaments being dyed or pigmented by a high visibility fluorescent pigment, and wherein the fabric meets the ANSI 107-1999 standard for chromaticity, luminance, opacity and durability.

2. The garment of claim 1, additionally including stripes of retroreflective material on said back and chest-covering portions of the fabric.

3. The garment of claim 2, wherein the stripes of retroreflective material extend horizontally around the garment across said chest-covering portions and said back-covering portion.

4. The garment of claim 3, additionally including stripes of retroreflective material extending vertically from the chest-covering portion to the back-covering portion.

5. The garment of claim 1, including a hem extending around peripheral edges of the fabric, said hem being formed by heat-sealing.

6. The garment of claim 1, wherein the spunbond nonwoven fabric has a basis weight of from 50 to 150 grams per square meter.

7. The garment of claim 1, wherein the spunbonded nonwoven fabric comprises polyester filaments.

8. The garment of claim 1, wherein the spunbond nonwoven fabric includes matrix filaments formed of polyethylene terephthalate homopolymer and binder filaments of a polyethylene isophthalate copolymer.

9. The garment of claim 8, wherein the spunbond nonwoven fabric formed of substantially continuous filaments is area bonded at points of filament intersection.

10. The garment of claim 1, wherein the fluorescent dye or pigment comprises fluorescent red, fluorescent yellow, or fluorescent red-orange.

11. The garment of claim 1 , wherein fabric is dyed with a fluorescent dye using a jet dye process.

12. A high visibility safety vest comprising a flexible high visibility fabric having portions configured for covering the back and chest of a wearer, the chest covering potion comprising left and right front panels that are each separately attached to the back portion and define a chest opening and a neck opening, said flexible high visibility fabric comprising a spunbond nonwoven fabric formed of substantially continuous polyester filaments, said filaments being dyed or pigmented by a high visibility fluorescent pigment, and wherein the fabric meets the ANSI 107-1999 standard for chromaticity, luminance, opacity and durability.

13. The safety vest according to claim 12, wherein the vest further comprises arm openings.

14. The safety vest according to claim 12, additionally including stripes of retroreflective material on said back and chest covering portions of the fabric.

15. The safety vest of claim 14, wherein the stripes of retroreflective material extend horizontally around the garment across said chest-covering portions and said back-covering portion.

16. The safety vest of claim 15, additionally including stripes of retroreflective material extending vertically from the chest-covering portion to the back-covering portion.

17. The safety vest according to claim 12, wherein the spunbond nonwoven fabric includes matrix filaments formed of polyethylene terephthalate homopolymer and binder filaments of a polyethylene isophthalate copolymer.

18. The safety vest according to claim 12, wherein the polyester filaments are thermally bonded.

19. The safety vest according to claim 12, wherein the spunbond nonwoven fabric has a basis weight of from 50 to 150 grams per square meter.

20. The safety vest according to claim 12, wherein the left and right front panels are attached to the back covering portion at the shoulders with a heat seal.

21. The safety vest according to claim 12, further comprising fasteners for releasably attaching the left and right front panels together, said fasteners comprising Velcro, buttons, zipper, ties, or straps.

22. The safety vest according to claim 12, wherein the vest is a Class II garment under ANSI 107-1999 standards.