| Type
|
Description |
Advantages |
Disadvantages |
| |
Silver Eagle Outfitters Garments made
with water-retaining,
fibrous-based materials |
Special water-absorptive material is
extruded as fibre and blended to form water-retaining batting. This batting is combined with
shell fabric and microporous liner. To use, fabric
composite is soaked for five minutes. Works in similar manner as
granular materials without added bulk and with more complete cooling. |
The design is simple and natural.
The form of polymer used prevents
excessive weight gain and bulk.
Offers extensive cooling times
without re-wetting.
Size does not change when
activated. |
Garment must be wet before using;
however, the design of fabric eliminates wetting of
clothing and can be easily accomplished in rinse/spin cycles of washing machine or in a sink or bag
with tap-water. |
|
Ice Pack Vests |
Frozen or refrigerated solid material
pouches are placed in pockets of garments absorb
body heat. |
This is a very simple design and
can be used with a variety of garments. |
Requires refrigeration or freezer to
store pouches.
Are relatively heavy and cool only
where pouches
are located. |
|
Granular Materials |
Water-absorptive materials are
incorporated into fabrics. When wet, these fabrics
absorb body heat as water evaporates to allow heat
escape to outside environment. |
Relatively simple and easy to
use. |
Many existing products don't have
even distribution of granules.
Garments over-soak with water,
leading to excessive weight and bulk. |
|
Phase Change Materials |
Special liquids or polymers are
encapsulated as beads and are impregnated into
batting, foams, or other textiles. These beads
absorb heat from the body, but must be exposed to
cooler environment to release heat. |
Does not rely on refrigeration or
external means if activation.
Beads can be used in a variety of
forms. |
Provide limited heat absorption
capacity.
Activation of Phase Change Material
garments cause tightness and loss of mobility.
Early versions are similar to ice
pack vests.
Requires temperature differential for
recharging beads. |
|
Active |
|
Recirculating Systems |
Tubes sewn into vest recirculate
fluid using pumps; provides heat sink to remove heat
absorbed by the circulating fluid. |
Can have high-heat absorption
capacity for extended periods. |
Because these systems are extremely
heavy (due to pump and power supply), the weight
negates much of the cooling effect.
These are generally bulky and
difficult to use.
Are relatively expensive. |
