Flame resistant thermal liners and garments made with same

Abstract

Embodiments of the present invention replace relatively bulky nonwoven thermal insulating materials used in thermal liners with thin, lightweight, flexible films that maintain or improve TPP performance while reducing the thickness, and enhancing the flexibility, of the thermal liner so as to increase wearer comfort. Moreover, the films incorporated into the thermal liners can be both air and vapor permeable such that the TPP performance is not realized at the expense of THL performance. Rather, the THL performance of garments incorporating embodiments of thermal liners contemplated herein is comparable toif not improved overgarments formed with traditional thermal liners.

Claims

1. A garment composite comprising: a. an outer shell layer comprising a flame resistant fabric; b. a moisture barrier layer comprising a water-impermeable layer; and c. a thermal liner layer comprising a flame resistant facecloth, at least one free-standing film layer, and at least one textile layer, wherein the flame resistant facecloth, the at least one textile layer, and the at least one film layer are quilted together, wherein the at least one film layer is air and vapor permeable and water resistant and wherein the thermal liner comprises at least one of (1) a stiffness in at least one of a warp direction and a weft direction of less than 5 microjoules/meter, when tested pursuant to ASTM D 1388 (2014) (Option A, Cantilever Test Flexural Rigidity) and (2) a stiffness in at least one of a warp direction and aweft direction of less than 4 pounds force (lbf), when tested pursuant to ASTM D 4032 (2016), wherein the flame resistant facecloth is exposed on a first side of the garment composite and the outer shell layer is exposed on the second side of the garment composite.

2. The garment composite of claim 1, wherein the at least one film layer is adjacent the moisture barrier layer in the garment composite.

3. The garment composite of claim 1, wherein the at least one textile layer comprises at least two textile layers and wherein the at least one film layer comprises at least two film layers.

4. The garment composite of claim 3, wherein the at least two film layers and the at least two textile layers alternate within the thermal liner layer.

5. The garment composite of claim 4, wherein one of the two textile layers is adjacent the flame resistant facecloth.

6. The garment composite of claim 1, wherein the at least one textile layer comprises a spunlace comprising a weight between 0.5-1.4 osy.

7. The garment composite of claim 1, wherein the at least one textile layer comprises apertures.

8. The garment composite of claim 1, wherein the at least one film layer comprises expanded polytetrafluoroethylene.

9. The garment composite of claim 1, wherein the at least one film layer comprises a weight of 0.3-2.0 osy.

10. The garment composite of claim 1, wherein the at least one film layer comprises a weight of no more than 1.2 osy.

11. The garment composite of claim 1, wherein the thermal liner layer has a char length of 4 inches or less and an afterflame of 2 seconds or less when tested pursuant to ASTM D 6413 (2015).

12. The garment composite of claim 1, wherein the garment composite has a thermal protective performance rating of at least 35 calories/cm.sup.2 when tested pursuant to ISO 17492 (2003), as modified by NFPA 1971 (2013).

13. The garment composite of claim 1, wherein the garment composite has a thermal heat loss of at least 205 watts/m.sup.2 when tested pursuant to ASTM F 1868 (2002), as modified by NFPA 1971 (2013).

14. A garment composite comprising: a. an outer shell layer comprising a flame resistant fabric; b. a moisture barrier layer comprising a water-impermeable layer; and c. a thermal liner layer comprising a flame resistant facecloth, at east one free-standing film layer, and at least one textile layer, wherein the flame resistant facecloth, the at least one film layer, and the at least one textile layer are quilted together and wherein the at least one film layer is air and vapor permeable and water resistant and wherein the thermal liner layer comprises at least one of (1) a stiffness in at least one of a warp direction and a weft direction of less than 5 microjoules/meter, when tested pursuant to ASTM 01388 (2014) (Option A, Cantilever Test, Flexural Rigidity) and (2) a stiffness in at least one of a warp direction and a weft direction of less than 4 pounds force (lbf), when tested pursuant to ASTM D 4032 (2016), wherein the flame resistant facecloth is exposed on a first side of the garment composite and the outer shell layer is exposed on a second side of the garment composite opposite the first side and wherein the garment composite has a thermal protective performance rating of at least 35 calories/cm.sup.2 when tested pursuant to ISO 17492 (2003), as modified by NFPA 1971, and a thermal heat loss of at least 205 watts/m.sup.2 when tested pursuant to ASTM F 1868 (2002), as modified by NFPA 1971.

15. The garment composite of claim 14, wherein: i. the at least one textile layer comprises at least two textile layers; ii. the at least one film layer comprises at least two film layers; iii. the at least two film layers and the at least two textile layers alternate within the thermal liner layer; iv. one of the two textile layers is adjacent the flame resistant facecloth; and v. one of the two film layers is adjacent the moisture barrier layer.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Illustrative embodiments of the present invention are described in detail below with reference to the following drawing figures:

(2) FIG. 1 illustrates a partial cut-away view of a prior art protective garment.

(3) FIG. 2 illustrates an exploded perspective view of a portion of the prior art protective garment illustrated in FIG. 1.

(4) FIG. 3 illustrates an exploded view of a portion of an embodiment of a thermal liner contemplated herein.

(5) FIGS. 4-10 graphically represent performance data set forth in Tables 2 and 4.

DETAILED DESCRIPTION

(6) The subject matter of embodiments of the present invention is described here with specificity to meet statutory requirements, but this description is not necessarily intended to limit the scope of the claims. The claimed subject matter may be embodied in other ways, may include different elements or steps, and may be used in conjunction with other existing or future technologies. This description should not be interpreted as implying any particular order or arrangement among or between various steps or elements except when the order of individual steps or arrangement of elements is explicitly described.

(7) Embodiments of the present invention replace relatively bulky nonwoven thermal insulating materials used in thermal liners with thin, lightweight, flexible films that maintain or improve TPP performance while reducing the thickness, and enhancing the flexibility, of the thermal liner so as to increase wearer comfort. Moreover, the films incorporated into the thermal liners can be both air and vapor permeable such that the TPP performance is not realized at the expense of THL performance. Rather, the THL performance of garments incorporating embodiments of thermal liners contemplated herein is comparable toif not improved overgarments formed with traditional thermal liners.

(8) More specifically, some embodiments of the thermal liners are formed as a composite of at least one layer of a flame resistant, thin, air and moisture vapor permeable, water resistant, flexible, insulating material, such as a film or membrane (film layer), in combination with a flame resistant, lightweight, low density, flexible, air and moisture vapor permeable, insulating textile or foam structure, such as spunlace/needlepunch or other nonwoven structure, textile, knit, etc. (textile layer).

(9) Air permeable as used herein means that air may pass through or permeate the material. Moisture vapor permeable or vapor permeable as used herein means that moisture vapor may pass through or permeate the material. Water resistant as used herein means that water may pass through the material upon application of pressure or in the event that the surface tension of the material is disrupted, such as in the case of soiling. This is in contrast to waterproof, whereby water cannot pass through the material even under substantial pressure.

(10) FIG. 3 depicts an embodiment of a thermal liner 30 contemplated herein (the composite is shown exploded for ease of discussion). In use, the thermal liner 30 would replace the thermal liner 20 in the garment of FIGS. 1 and 2. The thermal liner 30 includes a customary flame resistant woven or knitted facecloth 32.

(11) The thermal liner 30 of FIG. 3 further includes alternating film layers 34 and textile layers 36. While two film layers 34 and two textile layers 36 are shown in the embodiment of FIG. 3, as few as one film layer 34 and one textile layer 36 may be used and more than two layers of each may be used. The same number of film layers 34 and textile layers 36 can, but need not, be used. Moreover, multiple film layers 34 may be provided between adjacent textile layers 36 and vice versa (i.e., they need not alternate). In still other embodiments, the thermal liner 30 includes a facecloth 32 and one or more film layers 34 but is devoid of a textile layer 36.

(12) Either the film layer 34 or the textile layer 36 may be positioned adjacent the facecloth 32 of the thermal liner 30 and as the exposed layer on the opposite side of the thermal liner (i.e., the side adjacent the intermediate moisture barrier layer 14 in the garment 10 of FIG. 1). In some embodiments, it may be desirable for a film layer 34 to be exposed on the thermal liner 30 so as to be directly adjacent the intermediate moisture barrier 14 in the garment fabric. But, again, such an orientation is not required.

(13) The textile layer 36 can be one or more of a lightweight, low density, flexible, air and moisture vapor permeable, insulating textile or foam structure, such as a spunlace, needlepunch or other nonwoven structure, a woven material, a knitted material, etc. In some embodiments, the textile layer 36 is a nonwoven fabric, such as, but not limited to, a spunlace or needlepunch. Not all of the textile layers 36 provided in the thermal liner 30 need be the same. Rather, different textile layers 36 may be combined in different ways within the thermal liner 30.

(14) Textile layers 36 having a lower weight than those conventionally used in thermal liners may be, but do not have to be, used. For example, in some embodiments, a textile layer 36 weighs 0.3-5.0 osy, inclusive; 0.3-4.0 osy, inclusive; 0.3-3.0 osy, inclusive; 0.3-2.0 osy, inclusive; and/or 0.3-1.0 osy, inclusive. In some embodiments, a textile layer 36 weighs 0.5-1.4 or 0.5-1.0 osy, inclusive. In some embodiments, a textile layer 36 weighs 0.7-0.9 osy, inclusive. In some embodiments, a textile layer 36 weighs 0.8-0.9 osy, inclusive. The weight of a textile layer 36 may depend on the number of layers (textile layer(s) and/or film layer(s)) incorporated into the thermal liner 30. For example, if only a single textile layer 36 is used, it may be preferable that the textile layer be of a heavier weight than if multiple textile or film layers are used. Moreover, the weight of different textile layers 36 used in a thermal liner 30 can be the same or different.

(15) The textile layer 36 may be apertured or otherwise patterned, textured, etc. but need not be in all embodiments. If apertured, apertures of any size may be provided in the textile layer 36 in any density.

(16) In some embodiments, the film layer 34 is formed of a thin, air and moisture vapor permeable, water resistant, flexible, insulating material. In some embodiments, the film layer 34 serves to resist the passage of hot air through the thermal liner system to the wearer. In some embodiments, one or more of the film layer(s) 34 is an expanded polytetrafluoroethylene (ePTFE) film. A film layer 34 may be (1) vapor permeable, waterproof, and air impermeable (e.g., a capped ePTFE) or (2) air permeable, vapor permeable, and water resistant (e.g., an uncapped ePTFE, eVent, etc.).

(17) In other embodiments, one or more film layer(s) 34 can be formed of a flame resistant urethane having a microporous (air permeable, vapor permeable, and water resistant) structure or molecular sieve (vapor permeable, waterproof, air impermeable) structure. In still other embodiments, one or more film layer(s) 34 may be formed of combinations of ePTFE and urethane materials, such as, but not limited to, those described above. Furthermore, not all of the film layers 34 provided in the thermal liner 30 need be the same. Rather, different film layers 34 may be combined in different ways within the thermal liner 30.

(18) While a film layer 34 may be of any weight, it is preferably lightweight and weighs between 0.3-2.0 osy, inclusive; 0.3-1.5 osy, inclusive; and 0.5-1.2 osy, inclusive. The weight of a film layer 34 may depend on the number of layers (textile layer(s) and/or film layer(s)) incorporated into the thermal liner 30. For example, if only a single film layer 34 is used, it may be preferable that the film layer be of a heavier weight than if multiple film/textile layers are used. Moreover, the weight of different film layers 34 used in a thermal liner 30 can be the same or different. In some specific and non-limiting embodiments, a film layer 34 weighs no more than 1.2 osy.

(19) The facecloth 32, film layer(s) 34, and textile layer(s) 36 are preferably formed of materials (including, but not limited to, flame resistant materials) that, when incorporated into a thermal liner 30, permits the thermal liner 30 to comply with all of the applicable NFPA 1971 requirements, including, but not limited to, the thermal protective requirements of having a 4 inch (or less) char length and a 2 second (or less) afterflame when the thermal liner is tested pursuant to the testing methodology set forth in ASTM D 6413: Standard Test Method for Flame Resistance of Textiles (2015), the entirety of which is hereby incorporated by reference.

(20) To test for char length and afterflame, a fabric specimen is suspended vertically over a flame for twelve seconds. The fabric must self-extinguish within two seconds (i.e., it must have a 2 second or less afterflame). After the fabric self-extinguishes, a specified amount of weight is attached to the fabric and the fabric lifted so that the weight is suspended from the fabric. The fabric will typically tear along the charred portion of the fabric. The length of the tear (i.e., the char length) must be 4 inches or less when the test is performed in both the machine/warp and cross-machine/weft directions of the fabric. A fabric sample is typically tested for compliance both before it has been washed (and thus when the fabric still contains residualand often flammablechemicals from finishing processes) and after a certain number of launderings (5 launderings for NFPA 1971).

(21) It is contemplated that the facecloth 32, film layer(s) 34, and textile layer(s) 36 may be selected to render the entire thermal liner 30 stretchable. By way only of example, both the facecloth 32 and textile layer(s) 36 could be knitted fabrics and a stretchable film layer(s) 34 used.

(22) The thermal liner 30 can be assembled in a variety of ways. For example, in one embodiment, the facecloth 32, textile layer(s) 36, and film layer(s) 34 are quilted together to form the thermal liner 30. The film layer(s) 34 can be, but need not be, bonded to a supporting substrate (such as a textile layer(s)) prior to quilting. Rather, quilting the film layer(s) 34 directly to the facecloth 32 and textile layer(s) 36 may impart sufficient support to the film layer(s) 34 without sacrificing the flexibility of such layer(s) 34. In such cases, the film layer(s) 34 need not be bonded to or supported by a supporting substrate prior to quilting or attachment. In some embodiments, other attachment methods, such as lamination, can be used either in addition to, or instead of, quilting.

(23) Provided below in Table 1 is an example of a prior art thermal liner (Control Thermal Liner) and a non-limiting example of a thermal liner in accordance with embodiments of the invention (Inventive Thermal Liner). The various layers of the thermal liners were assembled and quilted together.

(24) TABLE-US-00001 TABLE 1 Thermal Liner Structure (top to bottom) Control Thermal Liner (Prior Art) 2.3 osy spunlace 1.5 osy spunlace Caldura Facecloth Inventive Thermal Liner 1.0 osy film 0.9 osy spunlace 1.0 osy film 0.9 osy spunlace Caldura Facecloth

(25) Definitions of the terminology used in Table 1 are as follows: The term 1.5 osy spunlace is a non-apertured flame resistant spunlace fabric formed with 67% meta-aramid/33% para-aramid fibers having a weight of approximately 1.5 osy. The term 2.3 osy spunlace is non-apertured flame resistant spunlace fabric formed with 67% meta-aramid/33% para-aramid fibers having a weight of approximately 2.3 osy. The term 0.9 osy spunlace is an apertured flame resistant spunlace fabric formed with 67% meta-aramid/33% para-aramid fibers having a weight of approximately 0.9 osy. The term 1.0 osy film is a flame resistant ePTFE film having a weight of approximately 1.0 osy. The film is uncapped so as to be both air and vapor permeable as well as water resistant. The term Caldura Facecloth refers to a flame resistant woven fabric formed of 100% para-aramid filament yarns in the fill direction woven with spun yarns in the warp direction formed of a blend of 65% rayon fibers/25% para-aramid fibers/10% nylon. The fabric weighs approximately 3.5 osy and is available from TenCate.

(26) Various properties of the Control Thermal Liner and the Inventive Thermal Liner were tested. The thickness of the thermal liners was tested pursuant to ASTM D 1777 (2015): Standard Test Method for Thickness of Textile Materials, incorporated herein by this reference. The stiffness of the thermal liners in both the warp and fill directions was tested pursuant both to ASTM D 1388 (2014): Standard Test Method for Stiffness of Fabrics (Option A, Cantilever Test, Flexural Rigidity) and to ASTM D 4032 (2016): Standard Test Method for Stiffness of Fabric by the Circular Bend Procedure, both of which are herein incorporated by this reference. For both ASTM D 1388 and ASTM D 4032, lower test result values correlate to a more flexible fabric.

(27) The thermal liner testing results are set forth in Table 2.

(28) TABLE-US-00002 TABLE 2 Stiffness ASTM D 1388 Stiffness Thickness Cantilever Test ASTM ASTM Flexural Rigidity D 4032 Thermal Weight D 1777 (microjoules/meter) (pounds force) Liner (osy) (inches) Warp Fill Warp Fill Control 7.5 .062 6.06 6.75 4.33 4.37 Thermal Liner Inventive 7.4 .05 1.93 3.74 2.16 1.74 Thermal Liner

(29) FIGS. 4-6 graphically display the thickness and stiffness results of Table 2. The Control Thermal Liner and the Inventive Thermal Liner were of approximately the same weight. But as is clearly evident from FIGS. 4-6, the Inventive Thermal Liner was thinner (on the order of 20% thinner) and much more flexible than the Control Thermal Liner. Thermal liners in accordance with some embodiments of the invention can have a stiffness in at least one (and possibly both) of the warp and weft directions of less than 5 microjoules/meter (/m), less than 4 /m, less than 3 /m, and less than 2 /m, when tested pursuant to ASTM D 1388 (Option A, Cantilever Test, Flexural Rigidity). Thermal liners in accordance with some embodiments of the invention can have a stiffness in at least one (and possibly both) of the warp and weft directions of less than 4 pounds force (lbs.f), less than 3 lbs.f, and less than 2 lbs.f, when tested pursuant to ASTM D 4032. Moreover, the Inventive Thermal Liner complied with all applicable requirements of NFPA 1971.

(30) The thermal liners described in Table 1 were incorporated into conventional material layups for firefighter's garments that comply with NFPA 1971 so as to form garment composites (i.e., fabric composites with an outer shell, moisture barrier, and thermal liner) for turnout gear. More specifically, the thermal liners were incorporated into the garment composites set forth in Table 3.

(31) TABLE-US-00003 TABLE 3 Outer Shell Moisture Barrier Thermal Liner Garment Pioneer CROSSTECH BLACK Control Composite 1 Thermal Liner Garment Pioneer CROSSTECH BLACK Inventive Composite 2 Thermal Liner Garment Agility CROSSTECH BLACK Control Composite 3 Thermal Liner Garment Agility CROSSTECH BLACK Inventive Composite 4 Thermal Liner

(32) Definitions of the terminology used in Table 3 are as follows: Pioneer refers to a 100% aramid (i.e., flame resistant) outer shell fabric available from TenCate. Agility refers to an aramid blended (i.e., flame resistant) outer shell fabric available from TenCate. CROSSTECH BLACK refers to a capped ePTFE layer laminated to a woven meta-aramid fabric layer. This moisture barrier is flame resistant, air impermeable, vapor permeable, and waterproof. CROSSTECH BLACK is available from Gore.

(33) The thermal liners were positioned in the garment composites such that the top layer of the thermal liner (see Table 1) was positioned adjacent the moisture barrier. The garment composites were tested for TPP and/or THL performance, and the results are set forth in Table 4 below.

(34) TABLE-US-00004 TABLE 4 TPP THL Garment (calories/cm.sup.2) (watts/m.sup.2) Composite (before wash) (before wash) 1 39.2 271.7 2 40.4 279.8 3 41 274.0 4 42.5 273.1

(35) FIGS. 7-10 graphically display the TPP and THL results of Table 4. Garment Composites 2 and 4 (having the Inventive Thermal Liner) surpassed both the TPP and THL requirements set forth in NFPA 1971. More specifically, they both had TPP ratings well above the required 35 calories/cm.sup.2 and THL values well above the required 205 watts/m.sup.2.

(36) Garment composites in accordance with some embodiments of the invention can have a TPP rating of at least 35 cal./cm.sup.2 and higher, at least 38 cal./cm.sup.2 and higher, at least 40 cal./cm.sup.2 and higher, at least 42 cal./cm.sup.2 and higher, and at least 44 cal./cm.sup.2 and higher. Garment composites in accordance with some embodiments of the invention can have a THL value of at least 250 watts/m.sup.2 and higher, at least 260 watts/m.sup.2 and higher, at least 270 watts/m.sup.2 and higher, and at least 280 watts/m.sup.2 and higher.

(37) Garment composites in accordance with embodiments of the invention comply with the requirements of NFPA 1971, as well as the equivalent European standard, EN 469 (2005): Protective Clothing for Firemen (and subsequent editions), and the equivalent international standard, ISO 11999 (2015): PPE for firefightersTest methods and requirements for PPE used by firefighters who are at risk of exposure to high levels of heat and/or flame while fighting fires occurring in structures (and subsequent editions), all of which are herein incorporated by reference. More specifically, they comply with (1) the Heat Transfer Index (the European equivalent to TPP) requirements, when tested pursuant to EN 367 (1992): Protective clothing; protection against heat and fire; method for determining heat transmission on exposure to flame and its essential equivalent EN ISO 9151 (2016): Protective clothing against heat and flame; determination of heat transmission on exposure to flame, as well as (2) the Water Vapor Resistance (abbreviated R.sub.ET and the European equivalent to THL) requirements, when test pursuant to EN 31092 (1993): Textiles; physiological effects; measurement of thermal and water-vapour resistance under steady-state conditions (sweating guarded-hotplate test), and its essential equivalent EN ISO 11092 (2014): Textiles; physiological effects; measurement of thermal and water-vapour resistance under steady-state conditions (sweating guarded-hotplate test). All of the referenced standards and any subsequent editions thereof are herein incorporated by reference.

(38) The conventional wisdom in the industry has been that relatively bulky thermal liners are required to impart the necessary TPP to the garment. However, embodiments of the thermal liners described herein demonstrate such is not the case. As evident from FIGS. 7 and 8, garment composites that include the Inventive Thermal Liner had TPP values that exceeded the TPP values of garment composites formed with conventional thermal liners (such as Control Thermal Liner), but that were otherwise identical. This is despite the fact that the Inventive Thermal Liner is thinner and less bulky than the Control Thermal Liner. Moreover, while affording the wearer better protection, garment composites formed with the Inventive Thermal Liner are also more comfortable to wear, given the thinner and more flexible nature of the Inventive Thermal Liner (and thus of the garment into which it is incorporated). A garment that is easier to maneuver within reduces the stress on the wearer.

(39) The conventional wisdom in the industry has also been that films incorporated into garment composites detrimentally impact the THL value of the garment. Embodiments of the present invention prove that wisdom wrong. Rather, inclusion of a film layer(s) in embodiments of the thermal liner contemplated herein did not detrimentally impact the ability of the garment to allow heat and moisture vapor to escape from the wearer. As demonstrated in FIG. 9, the garment composite that included the Inventive Thermal Liner (Garment Composite 2) had a THL value that exceeded the THL value of the garment composite formed with a conventional thermal liner (such as Garment Composite 1 formed with the Control Thermal Liner), but that were otherwise identical. Moreover, the THL values of Garment Composites 3 and 4 were almost identical. See FIG. 10. Inclusion of air and vapor permeable film layers in the Inventive Thermal Liner permitted heat and vapor to escape from the wearer through the thermal liner.

(40) Thus, a thinner, more flexible thermal liner may be incorporated into turnout garments without sacrificingand indeed improvingthe thermal performance (i.e., TPP) and heat management (i.e., THL) properties of the garment. In any event, garment composites that incorporate embodiments of the thermal liners contemplated herein will pass the TPP and THL requirements (as well as all other applicable requirements) of NFPA 1971.

(41) Different arrangements of the components described above, as well as components and steps not shown or described are possible. Similarly, some features and subcombinations are useful and may be employed without reference to other features and subcombinations. Embodiments of the invention have been described for illustrative and not restrictive purposes, and alternative embodiments will become apparent to readers of this patent. Accordingly, the present invention is not limited to the embodiments described above or depicted in the drawings, and various embodiments and modifications can be made without departing from the scope of the invention.