Insulation material with vacuum compartments

An insulating sheet material is made of a plurality of air tight chambers, each having a partial vacuum therein, held together in closely spaced side-by-side relationship so as to form a sheet of such compartments. The insulating sheet may be formed of sheets of material bonded together so as to form the side-by-side compartments, or the compartments may be individually formed and secured in side-by-side relationship by a film of material to which the compartments are adhered. The insulation sheet is preferrably perforated between compartments so that the sheet can be easily torn to any desired size.

BACKGROUND OF THE INVENTION 
1. Field: 
The invention is in the field of insulation for building or other purposes. 
2. State of the Art: 
With the cost of energy continuing to rise, people have become energy 
conscious. As part of this energy consciousness, there has been a 
continuing search for improved insulating materials to be used 
particularly in building to reduce heat loss from or heat entry into 
buildings and homes. The most common insulating materials are fiberglass 
batting, expanded plastic foam and cellulose insulation made from 
newspapers and cardboard. U.S. Pat. No. 2,039,601 shows building panels 
having sealed air compartments therein that act as insulation. 
Vacuum has been known as an insulator, but has not been used in building 
materials. Since vacuum must be held in a chamber, and such chamber must 
be relatively strong, the use of vacuum as insulation has been limited to 
small containers such as thermos bottles. U.S. Pat. No. 3,150,793 shows a 
tank structure made up of insulating sections having vacuum therein while 
U.S. Pat. No. 3,769,770 shows a super insulating material made up of tiny 
spheres maintained in a vacuum and describes also another super insulating 
product made up of foil layers and fibrous material maintained in a 
vacuum. Such insulation may have as many as 75 layers per inch. These 
materials, however, are used only in special high heat applications and 
are not generally available or economical enough for use as building 
insulation. 
SUMMARY OF THE INVENTION 
According to the invention, insulating sheet material is made of a 
plurality of air tight, evacuated compartments held together in 
side-by-side relationship so as to form a sheet of such compartments. 
In one embodiment of the invention, the compartments are individually 
formed of material rigid enough to maintain its shape and not collapse as 
a result of the vacuum therein, or of a flexible material placed about a 
relatively rigid, porous material which holds the flexible material 
against collapse. 
In a second embodiment of the invention two sheets of flexible, air 
impervious material, such as sheet plastic, are sealed together in a grid 
pattern to form individual, evacuated pockets each containing 
substantially rigid, porous material which keeps the two sheets of 
flexible material spread apart with the vacuum inside the compartments. 
When using flexible material, the porous material may take a variety of 
forms such as corrugated cardboard, corrugated or honeycomb rigid plastic, 
or a plastic foam material. The purpose of the porous material is to hold 
the two layers of plastic apart against the vacuum inside the compartment 
while still providing space for the vacuum so that its insulating 
properties may be realized. It is preferred that the sheet be perforated 
between compartments so that it may be easily torn along such perforations 
to vary the size of the sheet to that needed for any particular 
application.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT 
As illustrated in the drawings, a sheet of insulation according to the 
invention has a series of side by side vacuum compartments 10. In one 
embodiment of the invention, these compartments are separated by a seam 
where two separate sheets of material 11 and 12, FIG. 2, have been joined 
together such as by heat sealing. If the sheets of material 11 and 12 are 
flexible, each vacuum compartment contains a substantially rigid, but 
porous material such as a block of corrugated cardboard 13, which spreads 
the flexible sheets 11 and 12 and holds them apart against the vacuum 
inside the compartment. The block of substantially rigid material 13 
should have low heat conductive properties so it will not substantially 
affect the benefit of the vacuum in the compartment in terms of resistance 
to heat transfer. Further, the material should be relatively porous so 
that the maximum benefit can be obtained from the vacuum in the 
compartment. Corrugated cardboard, corrugated or honeycomb plastic, or 
plastic foam has been found satisfactory as the porous materials, but 
various other porous materials may be used with comparative results. As 
used herein, the flexible material is any material that will not maintain 
the shape of the compartments when a vacuum is applied in the 
compartments. This material may be a polyolifin or polyamide plastic in 
the form of a sheet or film, or may be thicker, more rigid sheets of 
plastic material, but not rigid enough to hold their shape against a 
vacuum in the compartment. Thus, the porous reinforcing material is 
necessary. 
It is preferred that the insulation sheets be perforated as at 14 along the 
seal between compartments so that it can be torn and separated along such 
perforations without breaking the seal to any of the compartments and 
allowing air to enter. With the perforations, the insulating material may 
come in rolls with the needed length for any particular space to be 
insulated merely torn off along the closest perforations. The rolls would 
come in standard widths to fit standard building framing, but again, if a 
narrower width is needed, the sheet may be merely ripped along the nearest 
perforation to the desired size. While FIG. 1 shows the sheet only three 
compartments wide, this is done merely for illustration purposes as the 
sheets will normally be wider. For example, the compartments may each be 
two inches square in size with a thickness of at least one-half inch, with 
the seam between compartments being about one-half inch or less. 
In a building, the insulation may be installed with the sheet between studs 
and behind obstructions such as electrical boxes, romex wiring, electrical 
conduits, or plumbing in a variety of ways. The insulation sheet may be 
installed flat between wall studs 15 with the compartments 10 against the 
wall 16 as shown at 17 in FIG. 3, any extra width of the insulation sheet 
being adjusted by placing one or more compartments with an edge to the 
wall as shown at 18. If more thickness of insulation is desired, the sheet 
can be folded upon itself so that the edges of the compartments are all 
against the wall as at 19 in FIG. 4. It can also be placed about small 
pipes such as indicated by reference 20 in FIG. 5 or larger pipes 21 as 
shown in FIG. 6. 
The insulation may be installed by gluing it in place, using nails or 
staples placed in the studs so as to hold the insulation in place, but not 
pierce any of the compartments, holding it in place with electrical or 
other braces, or holding it by any other suitable means. 
FIG. 7 shows an embodiment of the invention wherein the compartments 22 are 
individually formed of a material rigid enough to hold its shape and not 
collapse with a vacuum in the compartment. The individual compartments 22 
are secured in side-by-side configuration by adhering them to a film of 
flexible material 23 in any suitable manner. A second film of flexible 
material 24 may be adhered to the opposite side of the compartments 22, if 
desired. The sheets 23 and 24 may each be a continuous film to form an 
insulating sheet where the films cover one or both faces of the entire 
sheet, or the films 23 and 24 may be in the form of a web such as shown at 
25 in FIG. 8 so that they only partially cover the faces. In either case, 
the rigid compartments can be held closely together to prevent heat flow 
between the compartments. 
Again, it is preferred that the film material 23, 24 or 25 be perforated as 
at 26 between compartments so that the sheets can be easily torn to form 
insulating sheets of any desired size, without damage to the compartments. 
FIG. 9 shows a further embodiment which uses two sheets 30 and 31 of rigid 
material which is molded, heat formed, or vacuum formed and which has 
seams coming together as for the flexible material of FIG. 2. This 
material may be perforated as at 32 so the sheet can be easily broken 
along such perforations and separated into sheets of desired size. Rather 
than coming together at a seam intermediate the faces of the insulation 
sheet as shown in FIG. 9, the compartments could be formed in one of the 
sheets of rigid material and sealed to a substantially flat second sheet 
to from similar compartments. 
The rigid material used may be a polycarbonate plastic such as that sold 
under the trademark LEXAN by General Electric. This plastic is strong and 
has good fire retardant properties. If other types of plastic are used, it 
may be desirable to treat the plastic material, or any porous filler 
materials with fire retardant. It may also be desirable to use a foil or 
plastisized foil as the film material holding the compartments in 
side-by-side relationship. The foil material could be used on both faces 
of the sheet or could be used on one face of the sheet while other plastic 
film or butcher paper material is used on the other face. If foil is used 
on only face, when installed, the foil side of the sheet would preferrably 
be toward the interior space of the building. Where flexible material is 
used as shown in FIG. 2, one or both sheets of such material could be a 
plastisized foil material. 
It should be realized that individual compartments could also be made of a 
flexible material positioned about a rigid porous material so that the 
compartments would be as illustrated in FIG. 2, but would be separately 
formed and secured in side-by-side relationship by a film as shown in FIG. 
7. 
FIG. 10 shows a sheet of insulation material wherein the vacuum 
compartments are secured together in side-by-side relationship to form 
insulation sections 33 which are separated by flat sections 34 of film 
material without the compartments and which sections are the width of 
normal wall studs so that the insulation sheet can be installed along a 
wall with insulation sections 33 fitting between studs and sections 34 
going over the studs and being secured thereto by staples, nails, or 
merely held in place by the wall material secured to the studs. 
FIG. 11 shows the invention applied to an insulated window pane. As shown, 
two panes of glass or transparent plastic 35 and 36 are spaced apart by 
spacers 37 about their periphery. The area between the panes is evacuated 
and a flexible plastic material 38 is sealed about the window panes and 
spacers to form a sealed unit. This construction is particularly useful 
for the smaller window panes used in many older windows. This makes it 
easy to replace such older single panes with insulated panes which are not 
otherwise available. 
As used herein, a vacuum within a compartment refers to a partial vacuum. 
Of course, the greater the vacuum, the greater the insulating properties 
therof. The material forming the compartments, whether flexible or rigid, 
must be impervious to the flow of air therethrough. While the insulating 
material has been described principally with reference to its use as 
sheets for building purposes, it should be realized that it could be used 
in various other applications such as for insulation in the walls of 
portable coolers or as packing material about items to be kept cold or at 
stable temperatures. 
The individual vacuum compartments or the series of joined vacuum 
compartments of FIG. 2, may be formed of flexible material such as coated 
paper, film, or foil laminated over the porous material by a vacuum bag 
sealer machine such as Audion vacuum bag sealer Series VB, or Series V 
manufactured by PackagingAids Corporation of San Francisco, Calif. 
Whereas this invention is here illustrated and described with specific 
reference to an embodiment thereof presently contemplated as the best mode 
of carrying out such invention in actual practice, it is to be understood 
that various changes may be made in adapting the invention to different 
embodiments without departing from the broader inventive concepts 
disclosed herein and comprehended by the claims that follow.