Trauma mitigation and pressure reducing composition

Details Trauma mitigation and pressure reducing composition Trauma mitigation and pressure reducing composition

2001-08-08

2003-01-21

Foelak, Morton (Department: 1711)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Cellular products or processes of preparing a cellular...

C521S055000, C523S218000, C523S219000, C036S071500, C036S089000, C036S093000

Reexamination Certificate

active

06509385

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to a composition comprising a viscous fluid, macroparticulates such as foamed polystyrene, polypropylene, or polyethylene beads, and ceramic microparticulates, to be used in various articles or devices to impart improved mitigation of the impact of trauma or an improved reduction in pressure.
BACKGROUND OF THE INVENTION
Various compositions, articles and devices for reducing the impact of collision or reducing pressure are known in the art. For example, it is known to make impact resistant molded articles out of polystyrene or similar resin as described in U.S. Pat. No. 6,153,698, and impact resistant molded articles out of polypropylene for use in automobile inner and outer trim, as described in U.S. Pat. No. 6,124,934. It is also known to make fluid or fluid/particulate filled cushions. In some prior art types of liquid filled or deformable cushions, water is used as a prime constituent of the fluid compositions, as described in prior art U.S. Pat. No. 5,100,712. However, compositions having primarily water are too high in weight, a drawback when the filled articles are to be used as padding, for example in sports helmets, or inside articles fashioned to provide impact resistance in vehicles. Systems which are primarily water also have unsatisfactory rheological characteristics because they are newtonion. Other prior art fluid compositions for cushions include mineral oil or alcohol liquids as described in U.S. Pat. No. 5,093,138; these suffer from similar Theological or density disadvantages described for the water-based compositions.
Fluid/particulate compositions are described, for example, in U.S. Pat. Nos. 5,590,430 and 5,475,882, incorporated herein by reference, which provide a fluid composition which includes ceramic and plastic microspheres. While suitable for a cushion, plastic microspheres are not effective in providing appropriate resistance to high levels of trauma when used in articles in an externally imposed trauma environment such as that found in a collision of an automobile. Plastic microspheres are not suitable in high temperature situations and are also expensive, so that compositions for use in large articles are high in cost. U.S. Pat. No. 5,421,874 describes a similar fluid/particulate composition for use in cushions. However, there is no description in the prior art of a low density fluid/particulate composition suitable for providing impact resistance, trauma mitigation or pressure reduction, using lower cost materials.
SUMMARY OF THE INVENTION
The present invention is directed to a low density composition comprising a viscous fluid, macrosphere particulates of a foamed polymer such as polystyrene, polypropylene, or polyethylene, alone or in combination with ceramic microparticulates, which in one embodiment can be used to mitigate or dissipate the impact of trauma. The macroparticulates of the present invention, when consisting of foamed polymer beads, are an inexpensive, low-density material which can impart a greatly increased mass to a composition without additional weight, suitable for use in large articles. When low density or rapid displacement is not a particular concern, ground rubber tire particles can also be used as the macroparticulates. Use of either type of macroparticulate, when used in compositions of the present invention, will provide an improved mitigation of the impact of trauma. For example, the composition can be used in devices placed in the footwell of motor vehicles (or in other locations in the vehicle), or in airplane seats, to reduce the impact of a collision. The composition can also be used, for example, in bicycle helmets, chest or knee pads and sport helmets worn by hockey and football players, to reduce injury due to collision during play.
In another embodiment, this invention is directed to a composition for insert within a flexible cushion or other type of padding to be used, for example, in crutch pads or other orthopedic devices and which can reduce the pressure felt by a person when using the cushion as a seat or the device including the padding. The composition can also be used in the dual layered cushions disclosed in U.S. Pat. No. 5,195,199, incorporated herein by reference, or the '430 patent described above. The composition of the present invention can also be used in combination with the compositions of the '430 and '882 patents.
It is an object of the present invention, therefore, to provide a low density composition which imparts improved mitigation of the impact of trauma.
It is an additional object of the invention to provide a low density composition which can be used to reduce the amount of pressure felt by a person when using an article or device filled with this composition.
It is a further object of the present invention to provide a low density composition which can withstand higher temperatures experienced by vehicles in extreme environments.
It is a further object of the present invention to provide a low density composition comprising a viscous fluid in combination with macroparticulates and ceramic microspheres, suitable for use in trauma mitigation devices.
These and other objects of the invention will be more fully understood from the following description and the claims appended hereto.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention provides a deformable low density trauma mitigation or pressure reducing composition comprising a viscous fluid in an amount of about 50-80% by weight of the total composition, a plurality of macroparticulates dispersed within the viscous fluid, and, optionally, a plurality of ceramic microparticulates dispersed within the viscous fluid, the particulates of various sizes present in an amount of about 20-50% by weight of the total composition. When used in combination, the ratio of macroparticulates to microparticulates, based on weight, is from about 1:5 to about 1:20; more preferably, the ratio of macroparticulates to microparticulates is between about 1:5 to about 1:10.
As used herein, the term “viscous” refers to a viscosity measurement of from about 300,000 CPS to about 6 million CPS, with a preferred range of about 1 to 4 million CPS.
As used herein, the term “deformable” refers to the ability of the composition to change in shape in response to an external force.
As used herein, the term “macroparticulates” refers to foamed polymer beads comprised of polystyrene, polyethylene, polypropylene, or other air-chambered or blown particles. When low density is not required, ground rubber tire pieces or other types of ground rubber can also be used as the macroparticulates of the present invention. When foamed polymer beads are used, they can be spherically shaped, having an average diameter of about 0.5 mm to 5 mm and average density of about 2-10 lbs/cubic foot. The foamed polymer beads can also be oblong or football shaped (and are approximately of the same size and density of the spherical particles), depending on the desired end use. It is thought that oblong-shaped macroparticulates make the resulting composition more slowly displaceable and better able to repel dynamic forces, although the inventor does not wish to be bound by this. Thus, a composition comprising oblong macroparticulates might be better suited for use in knee pads to be worn by a football player. In contrast, use of spherical macroparticulates results in a more easily displaced composition which is better suited to repel static forces, e.g., better suited for use in articles such as seats. When ground rubber tire pieces are used as the macroparticulates, they will preferably be in the size range of about ⅛ to {fraction (5/16)} inch.
Preferred macroparticulates of the present invention are the foamed polymer beads; most preferred are the polypropylene beads sold under the tradename EPERAN available from Kaneka Texas Corporation of Bayport, Tex.
As used herein, the term “microparticulates” refers to ceramic microspheres or other rigid walled microparticulates composed of glass, metal or the like, havin

Affiliated with

Also associated with

Rating

Trauma mitigation and pressure reducing composition does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Trauma mitigation and pressure reducing composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Trauma mitigation and pressure reducing composition will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3071513