Garment thermal liner having insulating beads

A lightweight thermal liner suitable for use with a garment which provides thermal protection for the garment without the stiffness and bulk of conventional prior art thermal liners. In a preferred embodiment, the thermal liner includes a fabric substrate and a layer of relatively incompressible, lightweight insulating beads bonded to the substrate. The insulating beads are spaced on the substrate in a spaced array and create an insulating air space between the substrate and an adjacent layer of material in the garment. Also in a preferred embodiment, the thermal liner is made of flame and heat resistant material such as aramid or PBI fibers.

The present invention relates to garment thermal liners and, more 
particularly, to lightweight thermal liners for cold weather and hazardous 
duty garments to provide thermal protection for a wearer. 
Outer garments used by utility workers, firefighters, factory emergency 
workers and the like often are designed to provide thermal protection in 
hot and cold environments, as well as provide the wearer protection from 
injury from short bursts of flame, blasts of superheated air, steam and 
sparks. For example, such garments adapted to be worn by firefighters 
typically include an outer shell, a moisture barrier and a thermal liner 
which cooperate to protect against abrasion, moisture and temporary bursts 
of heat and flame. 
One typical firefighting ensemble comprises a turnout coat and pant or 
coveralls, each of which has an outer shell, a moisture barrier located 
within the outer shell, and a thermal liner. The outer shell typically is 
constructed of a flame and heat resistant material such as woven fabric of 
aramid and/or polybenzamidazole ("PBI") fibers. Commercially available 
aramid fibers are NOMEX and KEVLAR (both are trademarks of E.I. DuPont de 
Nemours & Co., Inc.). The moisture barrier typically includes a membrane 
layer, which is moisture vapor permeable but is impermeable to liquid 
moisture and air, bonded to a substrate of a flame and heat resistant 
material, such as the aramid or PBI material of the outer shell, only 
lighter in weight. Typically, the moisture barrier is made of expanded 
polytetrafluoroethylene ("PTFE"), such as GORE-TEX (a trademark of W. L. 
Gore & Associates, Inc.). The thermal liner is typically positioned within 
the moisture barrier in order to prevent it from soaking up liquid 
moisture flowing through the outer shell from the ambient environment and 
comprises a nonwoven or batting of aramid fibers. 
A recently-developed firefighting ensemble comprises a turnout coat and 
pant, or coveralls, having an outer shell, a moisture barrier and a 
thermal liner positioned between the outer shell and moisture barrier. The 
thermal liner includes a layer of a flame and heat resistant closed-cell 
apertured foam attached to a substrate of woven NOMEX by a suitable 
adhesive. The foam material is a neoprene or polyvinyl nitrile foam 
treated with antimony oxide to enhance flame and heat resistance. Examples 
of commercially available suitable foams are ENSOLITE brand closed-cell 
foam styles IV1, IV2, IV3, IV4, IV5, GIC and IVC, manufactured by 
Ensolite, Inc. of Mishawaka, Ind. 
Each layer of the ensemble must meet National Fire Protection Association 
("N.F.P.A.") standard 1971 ("Protective Clothing for Structural Fire 
Fighting") which includes standards for heat and flame resistance and tear 
strength. For example, the outer shell must be able to resist burning, 
melting, dripping, excessive shrinkage and separation at a temperature of 
500.degree. F. for five minutes. All layers combined must provide a 
thermal protection performance ("TPP") rating of at least 35. 
The moisture barrier and thermal liner are often stitched together to form 
a unitary component which is removably attached to the outer shell by 
snaps and/or hook and loop fasteners. While the combined moisture barrier 
and thermal liner may be removable from the outer shell, in most cases, 
this component is not designed to be worn separately apart from the outer 
shell, because it lacks such items as a front closure mechanism (e.g. a 
slide fastener), a collar, or an outer layer of material to protect the 
component from abrasion. 
A typical cold-weather ensemble, such as ski apparel, comprises a coat and 
pant or coveralls, each of which has an outer shell and an inner liner 
located within the outer shell. Conventionally, the thermal protection 
provided by the coat results from a synthetic filler or down sandwiched 
between the outer shell and the inner liner. Such insulation tends to make 
the garment bulky and consequently, restrict movement by the wearer. 
Typically, for both hazardous duty and cold weather garments, the 
insulation layer accounts for a large percentage of the weight of the 
garment. Furthermore, since most conventional thermal liners rely on 
thickness or "loft" from fibers or closed air cells to trap air to provide 
heat insulation, such liners tend to be bulky, compress easily--resulting 
in inconsistent thermal protection--and restrict movement of the wearer. 
Such movement restriction increases the effort required to move while 
wearing the garment, which increases the level of stress imposed on the 
wearer. Such stress level increase may become a critical factor when the 
associated garment is designed for wear by a firefighter, utility worker 
or emergency worker. 
Accordingly, there is a need to provide a garment with a thermal liner 
which is capable of providing adequate insulation at minimal weight, 
thickness and bulk. Furthermore, there is a need for such a thermal liner 
to be resistant to moisture absorption so that it can be positioned 
outside of a garment moisture barrier, an orientation which enhances 
moisture vapor transport from the wearer. 
SUMMARY OF THE INVENTION 
The present invention is a lightweight thermal liner suitable for use with 
a garment which provides thermal protection for the garment without the 
stiffness, thickness and bulk of conventional prior art thermal liners. In 
a preferred embodiment of the invention, the thermal liner comprises a 
fabric substrate and a layer of relatively incompressible, lightweight 
insulating beads bonded to the substrate. The insulating beads are 
positioned on the substrate in a spaced array and create an insulating air 
space between the substrate and an adjacent layer of material in the 
garment. 
In an embodiment adapted for use in a firefighter garment, the thermal 
liner is constructed of flame and heat resistant materials such that the 
thermal liner meets applicable performance criteria of the N.F.P.A. 
standard (National Fire Protection Association), and the like. 
In accordance with one embodiment of the present invention, the thermal 
liner of the present invention is incorporated into a garment which also 
includes an outer shell. The thermal liner includes a fabric substrate and 
a layer of insulating beads bonded to the substrate such that an air gap 
is created between the outer shell and substrate around the insulating 
beads. This air gap provides thermal protection for a wearer. 
In a second embodiment of the present invention, the thermal liner is 
incorporated into a firefighter ensemble comprising an outer shell, a face 
cloth, and a moisture barrier positioned between the outer shell and face 
cloth. The thermal liner of the present invention is positioned between 
the outer shell and moisture barrier. With this embodiment, the thermal 
liner substrate is made of a flame and heat resistant material such as an 
aramid or PBI fiber. Consequently, both the substrate and beads meet 
requirements as found in N.F.P.A. type standards such that the entire 
ensemble meets the relevant N.F.P.A. 1971 performance requirements for a 
firefighting turnout garment. The moisture barrier includes a substrate 
and a semi-permeable membrane bonded to the substrate. The substrate can 
be made from the same material as the fabric substrate of the thermal 
liner. 
In a third embodiment of the present invention, the thermal liner is 
incorporated in a firefighter garment comprising an outer shell, the 
thermal liner of the second embodiment and a combination moisture 
barrier/face cloth. The combination moisture barrier/face cloth comprises 
a layer of a semi-permeable membrane material, such as GORE-TEX, bonded to 
a substrate of a filament face cloth. The thermal liner is oriented such 
that the substrate faces outwardly. 
In a fourth embodiment of the present invention, the thermal liner of the 
present invention is incorporated into an ensemble comprising an outer 
shell and a combination moisture barrier/face cloth. With this embodiment, 
the thermal liner includes at least two fabric substrates, each of which 
carries a spaced array of insulating beads such that the substrates are 
spaced from each other by the beads. The thermal liner is positioned 
between the outer shell and the combination moisture barrier/face cloth. 
Alternately, the combination moisture barrier/face cloth is replaced by a 
discrete moisture barrier and face cloth. 
In a fifth embodiment, a firefighter garment is augmented with patches or 
pads comprising the thermal liner of the present invention. In one 
variation, the pads are positioned between the outer shell and thermal 
liner of the garment in strategic locations, such as the elbow, shoulder 
yoke or knees and act to increase the thermal resistance in such areas in 
response to external pressure, as well as add resiliency to those areas in 
response to increased loading, as from the pads and straps of SCBA 
Equipment. In other variations, the pads are positioned between the 
thermal liner and moisture barrier, and/or between the wearer and the face 
cloth to provide extra insulation in strategic areas. Alternately, such 
pads can be applied externally of the outer shell by pads covered with a 
patch of leather or aramid shell material, or can be applied to the outer 
surface of the outer shell such that the beads face outwardly and are 
exposed. 
The insulating beads employed in the garments preferably are made of 
silicone and do not appreciably absorb moisture. Consequently, the thermal 
liner of the present invention can be placed outside of the moisture 
barrier of a garment, an orientation which enhances moisture vapor 
transport from the wearer through the moisture barrier. 
In addition to the hazardous duty garments described above, the thermal 
liner of the present invention can be employed in conventional garments as 
well as career apparel such as coveralls and jumpsuits. 
Accordingly, it is an object of the present invention to provide an 
improved thermal liner which is relatively lightweight and of low bulk; a 
thermal liner which provides insulation from exterior temperature extremes 
sufficient to meet hazardous duty requirements and yet promotes 
breathability of the garment; a thermal liner which can be made of flame 
and heat resistant materials suitable for use in firefighter garments; a 
thermal liner which possesses relatively low moisture absorbing 
characteristics; a thermal liner having greater flexibility than thermal 
liners of comparable insulating capability; and a thermal liner which is 
relatively inexpensive and simple to construct. 
Other objects and advantages of the present invention will be apparent from 
the following description, the accompanying drawings and the appended 
claims.

DETAILED DESCRIPTION 
In the following embodiments, the insulating beads are preferably bonded to 
the fabric substrate of the thermal liner. However, those skilled in the 
art will appreciate that the insulating beads could be bonded to other 
layers of material of the garment, such as the outer shell, moisture 
barrier, and face cloth substrates or combinations thereof. 
As shown in FIG. 1, the thermal liner of the present invention is embodied 
in a cold-weather coat, generally designated 10. The coat 10 comprises an 
outer shell 12 and a thermal liner 14. As also shown in FIGS. 4 and 5, the 
thermal liner 14 includes a fabric substrate 16 and a layer of relatively 
incompressible, spaced insulating beads, generally designated 18, bonded 
to the substrate 16 and sandwiched between the outer shell 12 and the 
substrate 16 such that the beads face the outer shell. The coat 10 
includes a body portion 20, sleeves 22 and a collar 24 attached to the 
body portion. The outer shell 12 and liner 14 both include a front 
opening, and the shell includes a front closure 26 which includes snaps 
28, or alternatively a slide fastener (not shown). 
The outer shell 12 preferably is made from a material, such as nylon, 
polyester, cotton, or blends thereof, which is either inherently 
moisture-resistant, or treated to be such. The fabric substrate 16 is made 
from a suitable material, such as cotton or nylon. The insulating beads 18 
are made of polyvinyl chloride, silicone or other suitable material or 
combinations thereof, such that the beads are relatively incompressible. 
The beads 18 can be in any shape, such as spherical, tear-drop shaped, 
elliptical, square, rectangular, triangular, so long as an air gap is 
created between the fabric substrate 16 and any adjacent layer of material 
of the garment 10. Preferably, the beads 18 have a generally 
half-spherical shape, a diameter of about 3 millimeters and a height of 
about 1 mm. The preferred density of the beads 18 on the substrate 16 is 
in the range from about 5 to 7 beads per square centimeter. 
The insulating beads 18 can be bonded to the fabric substrate 16 by an 
appropriate adhesive or by self-adhesion upon the deposition of the 
material forming the beads 18 onto the substrate 16. The beads 18 create 
an air gap 30 (shown in FIG. 5) around the beads 18 and between the outer 
shell 12 and substrate 16. This air gap 30 provides thermal insulation, 
protecting the wearer of the coat 10 from ambient temperature extremes. 
Additionally, it is within the scope of the present invention that the 
materials described above for the cold-weather coat may be readily 
substituted with other materials having similar insulative properties. 
As shown in FIG. 2, the thermal liner 14 is incorporated in a cold-weather 
pant, generally designated 32. The pant 32 includes an outer shell 12 
which surrounds thermal liner 14. The thermal liner 14 may be attached to 
the shell 12 by hook and loop fasteners, snaps or the like (not shown). 
The shell 12 includes a front closure 34 which is secured by snaps 36, or 
alternatively a slide fastener (not shown). The insulating beads 18 are 
bonded to the substrate 16 of the thermal liner 14 according to the 
procedure set forth above. The beads 18 create an air gap 30 (illustrated 
in FIG. 5) around the beads 18 and between the outer shell 12 and 
substrate 16. This air gap 30 functions as a thermal protection means, 
protecting the wearer of the garment 32 from temperatures present in the 
surrounding environments. The outer shell 12, fabric substrate 16 and 
insulating beads 18 are made from the same materials as their 
corresponding elements in the coat 10 described above. 
As shown in FIG. 3, the thermal liner 14 of the present invention is 
incorporated into a cold-weather coverall, generally designated 38. The 
coverall 38 includes an outer shell 12 enclosing the thermal liner 14. The 
outer shell 12 includes a front closure 40 which is secured by a slide 
fastener 42, or alternatively by snaps (not shown). The insulating beads 
18 are bonded to the substrate 16 according to the procedure set forth 
above. The outer shell 12, fabric substrate 16 and insulating beads 18 
preferably are made from the same materials as their corresponding 
elements in the coat 10 and pant 32 described above. 
As shown in FIGS. 6 and 7, the thermal liner of the present invention is 
embodied in a firefighter turnout coat, generally designated 44. The 
turnout coat 44 comprises a body portion 46, sleeves 48 and a collar 50 
attached to the body portion. The coat 44 includes an outer shell 52, a 
thermal liner 54, and a combination moisture barrier/face cloth 56. The 
thermal liner 54 is positioned between the outer shell 52 and the moisture 
barrier/face cloth 56. 
The thermal liner 54 includes a fabric substrate 58 and a layer of 
insulating beads, generally designated 60, bonded to the substrate 58 and 
sandwiched between the moisture barrier/face cloth 56 and substrate 58. 
The insulating beads 60 create an air gap 62 (illustrated in FIG. 11) 
between the moisture barrier/face cloth 56 and the fabric substrate 58 and 
around the insulating beads 60. As with the embodiment of FIGS. 1-5, the 
insulating beads 60 preferably are made of polyvinyl chloride, silicone or 
other suitable material or combinations thereof, provided that the beads 
are relatively incompressible, and can be in any shape, such as spherical, 
tear-drop shaped, elliptical, square, rectangular, triangular, so long as 
air gap is created between the fabric substrate 16 and any adjacent layer 
of material of the garment 10. 
Preferably, the beads 60 have a generally hemispherical shape, a diameter 
of about 3 millimeters and a height of about 1 mm. The preferred spacing 
density of the beads 60 on the substrate 58 is in the range from about 5 
to 7 beads per square centimeter. The substrate 58 preferably is made of a 
relatively lightweight aramid material, such as NOMEX or KEVLAR and 
preferably is woven, although the substrate may alternately be a twill or 
satin weave. Alternatively, the substrate can be a lightweight cloth of 
other high heat resistant fiber such as PBI (polybenzamidazole). The 
weight preferably is in the range of 4-6 ounces per square yard. Although 
fabric of filament yarn is preferred, spun yarn fabrics, or combinations 
of spun yarn and filament yarn fabrics may be employed. With such a 
construction, the thermal liner 54 meets current oven test N.F.P.A. 1971 
standards, which include withstanding a temperature of 500.degree. F. for 
five minutes in a forced circulating air oven without melting, separating 
or igniting (oven test). 
If necessary, successive layers of such a thermal liner 54 may be placed 
adjacent to each other to provide the requisite thermal protection 
performance (TPP) factor to meet N.F.P.A. 1971 standards, namely, a TPP of 
35 or greater. Alternatively, the insulating beads 60 could be sandwiched 
between the outer shell 52 and the fabric substrate 58. As shown in FIG. 
6, the insulating beads 60 are bonded to the fabric substrate 58 of the 
thermal liner 54. 
The outer shell 52 is constructed of a flame and heat resistant material 
such as a woven fabric of aramid (such as NOMEX or KEVLAR) and/or PBI 
fibers. The outer shell 52 further includes a front closure 64 secured by 
snaps 66 and hook and loop closure components 68, it is within the scope 
of the invention to use additional closure means such as buttons, slide 
fasteners and the like. The shell 52 therefore meets the same N.F.P.A. 
1971 standards as does the thermal liner 54. 
The moisture barrier/face cloth 56 includes a moisture barrier membrane 70, 
which is moisture vapor permeable but is impermeable to liquid moisture 
and is wind resistant, bonded to a face cloth 72 (illustrated in FIGS. 10 
and 11). The moisture barrier membrane 70 preferably is made of expanded 
PTFE, more preferably GORE-TEX. The face cloth 72 is made of a lightweight 
material of aramids such as NOMEX. 
The collar 50 of the coat 44 is also provided with a closure or throat tab 
74 for securing the collar 50 around the wearer's neck. Reflective strips 
76 are stitched to the outer shell 52 at sleeves 48 and body portion 46 to 
increase visibility in low light conditions. 
Preferably, the thermal liner 54 and the moisture barrier/face cloth 56 
form an integral liner, generally designated 78, which is removably 
attached to the outer shell 52 as shown in FIG. 7. Liner 78 is secured to 
shell 52 by a slide fastener, or hook and loop fasteners (not shown) 
extending along the periphery of the liner front opening 79. 
Additionally, it is within the scope of the present invention that the 
materials described above for the firefighter turnout coat may be readily 
substituted with other materials having similar protective properties, or 
alternative protective properties corresponding to other specialized 
thermal garments. 
As shown in FIG. 8, the thermal liner 54 is embodied in a firefighter pant, 
generally designated 80. The pant 80 includes an outer shell 52, a thermal 
liner 54, and a combination moisture barrier/face cloth 56. The thermal 
liner 54 is positioned between the outer shell 52 and the combination 
moisture barrier/face cloth 56. The thermal liner 54 includes a fabric 
substrate 58 and a layer of insulating beads 60 bonded to the substrate 58 
and sandwiched between the combination moisture barrier/face cloth 56 and 
substrate 58. The insulating beads 60 create an air gap 62 (see FIG. 11) 
between the moisture barrier/face cloth 56 and the substrate 58 and around 
the insulating beads 60. The outer shell 52 includes a front closure 82 
which is secured by snaps 84. The outer shell 52, moisture barrier/face 
cloth 56, fabric substrate 58 and insulating beads 60 are made from the 
same materials and function in the same manner as their corresponding 
components in the turnout coat 44 described above. 
As shown in FIG. 9, the thermal liner 54 is embodied in a firefighter 
coverall, generally designated 86. The coverall 86 includes an outer shell 
52, a thermal liner 54, and a combination moisture barrier/face cloth 56. 
The thermal liner 54 is positioned between the outer shell 52 and the 
combination moisture barrier/face cloth 56. The thermal liner 54 includes 
a fabric substrate 58 and a layer of insulating beads 60 bonded to the 
substrate 58 and sandwiched between the combination moisture barrier/face 
cloth 56 and substrate 58. The insulating beads 60 create an air gap 62 
(see FIG. 11) between the moisture barrier/face cloth 56 and the fabric 
substrate 58 and around the insulating beads 60. The outer shell 52 
includes a front closure 88 which is secured by a slide fastener 90, or 
alternatively by snaps (not shown). The outer shell 52, combination 
moisture barrier/face cloth 56, fabric substrate 58 and insulating beads 
60 are made from the same materials as their corresponding elements in the 
turnout coat 44 and pant 80 described above. 
FIG. 10 is an enlarged view of a representative cut-away portion of any of 
the garments in FIGS. 6-9 showing the arrangement of the outer shell 52, 
the thermal liner 54, including the fabric substrate 58 and the layer of 
insulating beads 60, and the combination moisture barrier/face cloth 56. 
An air gap 62, as shown in FIG. 11, is created between the fabric 
substrate 58 of the thermal liner 54 and the combination moisture 
barrier/face cloth 56 and around the insulating beads 60. Air gap 62 
provides thermal protection to the wearer of the garment from ambient 
temperature extremes. The shell 52, liner 54 and moisture 
barrier/facecloth 56 are made of the same materials as their counterparts 
in the embodiment of FIG. 6. 
As shown in FIGS. 12, 13, and 18 the thermal liner of the present invention 
is incorporated into an external patch, generally designated 92, for use 
on a firefighting garment 93, which is similar to the turnout coat 44 
shown in FIG. 6. The patch 92 comprises an outer shell patch 94 and a 
patch 54' of thermal liner material. The thermal patch 54' includes a 
fabric substrate 58 and a layer of insulating beads 60 bonded to the 
substrate 58. The external patch 92 can be applied to the outer surface of 
the outer shell 52 of the firefighting garment 93 and positioned in 
strategic locations, such as the elbow, shoulder yoke or knees of the 
garment, also as shown in FIG. 21 for a turnout pant 95, which is similar 
in construction to coat 44 of FIG. 6. The insulating beads 60 create an 
air gap either between the outer shell patch 94 and the fabric substrate 
58, or between the outer shell 52 of the garment 93 or 95 and the fabric 
substrate, depending upon the orientation of the liner 54'. The outer 
shell patch 94 can be made from leather, or shell material, such as 
aramid, PBI or a combination thereof. The fabric substrate 58 and 
insulating beads 60 are made from the same materials as their 
corresponding elements in the thermal liner 54 of FIG. 6. 
As shown in FIGS. 19 and 20, the thermal liner 54" is incorporated into an 
internal pad, generally designated 96, for use in a firefighting garment 
93, shown in FIG. 18. The thermal liner 54" includes a fabric substrate 58 
and a layer of insulating beads 60 bonded to the substrate 58. The pad 96 
is preferably positioned between the outer shell 52 and thermal liner 54 
of the garment in strategic locations, such as the elbow, shoulder yoke or 
knees, as shown in FIGS. 18 and 21. The insulating beads 60 create air 
gaps between either the outer shell 52 of the firefighting garment and the 
fabric substrate 58 or the thermal liner 54 of the firefighting garment 
and the fabric substrate 58 depending upon the orientation of the liner 
54". The fabric substrate 58 and insulating beads 60 are made from the 
same materials as their corresponding elements in the firefighting turnout 
coat, pant and coveralls, described above with reference to FIGS. 6 and 7 
and generally provide the same function, adding increased thermal and 
abrasion resistance in areas of high compression. 
As shown in FIGS. 14 and 15, a representative cut-away portion of a 
garment, such as the garment 44 of FIG. 6, is modified to include a 
thermal liner 97 having several layers 54, each having a fabric substrate 
58 and a plurality of insulating beads 60 bonded thereto. This composite 
thermal liner 97 is positioned between the outer shell 52 and the 
combination moisture barrier/face cloth 56. An air gap 62', shown in FIG. 
15, is created around the insulating beads 60 of each layer 54 and between 
adjacent fabric substrates 58 and between an outer fabric substrate 58 and 
the moisture barrier/face cloth 56 (or outer shell 52, depending upon 
orientation). 
As shown in FIGS. 16 and 17, a representative cut-away portion of a garment 
similar to garment 44 of FIG. 6 is modified from the construction shown in 
FIGS. 10 and 11 in the following manner. The combination moisture 
barrier/face cloth 56 (see FIGS. 10 and 11) is replaced with two discrete 
components: a moisture barrier 98 and a face cloth 100. The moisture 
barrier 98 includes a substrate 102 and a moisture barrier membrane 70' 
bonded to the substrate 102. The substrate 102 is preferably made of a 
flame and heat resistant material such as the aramid or PBI material of 
the outer shell, only lighter in weight. The moisture barrier membrane 70' 
and the face cloth 100 are made from the same materials as their 
corresponding elements in the embodiments described above. 
As shown in FIG. 22, the thermal liner of the present invention is in the 
form of an external patch 103 for use on firefighting garments comprising 
a fabric substrate 104 and a layer of insulating beads 60 bonded to the 
fabric substrate 104 such that the beads 60 are facing outward, away from 
the outer shell 52 of a firefighting garment 44. The fabric substrate 104 
preferably is made from aramid fibers, but can be made from leather or 
PBI, or other flame and heat resistant material. The insulating beads are 
made from the same materials as described above. By positioning the 
insulating beads 60 to face outwardly, away from the outer shell 52 of the 
firefighting garment, the life of the firefighting garment, especially in 
areas of high stress, such as the knees, shoulder yoke and elbows, may be 
prolonged. 
Having described the invention in detail and by reference to the drawings, 
it will be apparent that modifications and variations are possible without 
departing from the scope of the invention as defined in the following 
claims.