Laminated thermal insulation sheeting

A laminated thermal insulation sheeting for covering ducts and pipes wrapped up by a thermal insulator such as glass wool and rock wool, includes an aluminum sheet and a metal network disposed on and over a surface of the aluminum sheet. A substantially transparent film of synthetic resin is placed on the metal network and has portions bonded to the surface of the aluminum sheet through interstices in the metal network. The aluminum sheet comprises aluminum foil or an aluminum-metallized film of synthetic resin, and may be lined with a backing material.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a laminated thermal insulation sheeting. 
2. Prior Art 
For thermally insulating ducts and pipes in which a coolant or heating 
medium flows to air-condition buildings, it is common practice to wrap up 
the ducts and pipes with a thermal insulator such as glass wool or rock 
wool, cover them with aluminum foil backed with kraft paper, and then 
fasten a honeycomb metal network therearound to hold the thermal insulator 
and metal network in position. 
Such procedure, however, it tedious and time-consuming, and is practically 
infeasible. Furthermore, the aluminum foil is exposed to ambient air and 
hence tends to become corroded, with the result that it will lose luster 
and its heat reflective characteristic will become poor in a relatively 
short period of time. 
SUMMARY OF THE INVENTION 
According to the present invention, a metal network is disposed on and over 
one surface of an aluminum sheet, and a substantially transparent film of 
synthetic resin is placed on the metal network, portions of the film being 
bonded to the one surface of the aluminum sheet through interstices in the 
metal network. 
It is an object of the present invention to provide a laminated thermal 
insulation sheeting having an aluminum sheet which can retain a desired 
degree of heat reflectivity for an increased period of time. 
Another object of the present invention is to provide a laminated thermal 
insulation sheeting having a relatively low coefficient of heat 
transmission. 
The above and other objects and advantages will become apparent from the 
following description when taken in conjunction with the accompanying 
drawings illustrating, by way of example, some preferred embodiments of 
the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
As shown in FIGS. 1 and 2, a laminated thermal insulation sheeting 10 
comprises an aluminum sheet 11, a network 12 made up of suitable metal 
wires and disposed on and over a surface 13 of the aluminum sheet 11, and 
a substantially transparent film 14 placed on the metal network 12. 
The aluminum sheet 11 comprises aluminum foil and is preferably backed or 
lined on its other surface 15 with a backing material 16 such as kraft 
paper, a textile fabric, a film of synthetic resin such as olefin or vinyl 
chloride, or layer of polyether or polyester foam, so as to reinforce the 
aluminum foil 11 and increase its degree of heat insulation. The metal 
network 12 has honeycomb interstices or open spaces 17 between adjacent 
wires (FIG. 1) and acts as a core member of the sheeting 10. The metal 
network 12 makes the overall sheeting 10 relatively semirigid so that the 
sheeting 10 can retain its configuration once put around the profiles of 
the ducts and pipes to the thermally insulated. 
The film 14 is made of suitable synthetic resin such as polyethylene, 
polypropylene, or ionomer, the thickness of the film 14 being in the range 
of from about 20 to about 50 microns. The film 14 has portions 18 bonded 
with or without adhesive to the surface 14 of the aluminum sheet 11 
through the interstices 17. It is preferable to utilize an extruder for 
applying the film 14 to the aluminum sheet 11 under pressure. 
In FIG. 2, the bonded portions 18 of the film 14 are spaced away from the 
wires of the metal network 12, thereby leaving air spaces 19 around the 
wires to give the sheeting 10 a low coefficient of heat insulation and to 
provide the wires with clearances in which they are displaceable to 
facilitate their bending and twisting when putting the thermal insulation 
sheeting 10 around the ducts and pipes. 
As illustrated in FIG. 3, a modified laminated thermal insulation sheeting 
20 includes an aluminum sheet 21 which comprises an aluminum-metallized 
film 22 of synthetic resin having an layer 23 of aluminum deposited 
thereon. A metal network 24 is placed on the aluminum layer 23 and the 
aluminum-metallized film 22 is lined with a backing material 25 on a 
surface remote from the aluminum layer 23. 
The aluminum sheet 11,21 thus covered with the transparent film 14 can 
maintain its luster or brightness and hence its good heat reflectivity for 
a long period of time. 
According to a modification shown in FIGS. 4 and 5, a plurality of 
substantially transparent film strips 26 of synthetic resin are placed on 
the metal network 12, the strips 26 being rectangular in shape and spaced 
from each other in side-by-side relation. FIG. 6 illustrates another 
modification in which a plurality of square film strips 27 are disposed on 
the metal network 12, each strip 27 being spaced from adjacent strips 27 
so that portions 28 of the metal network 12 which are not covered with the 
film strips 27 are in the form of a grid or checkerboard pattern. With the 
modifications of FIGS. 4 and 5, and 6, an unobstructed access is gained to 
the metal network 12 where it is not covered with the film strips 26,27. 
According to still another modification as shown in FIGS. 7 and 8, the 
substantially transparent film 14 covers the entire metal network 12, but 
there are portions 29 where the film 14 is not bonded to the aluminum 
sheet 11. The non-bonded portions 29 are rectangular in shape and are 
spaced from each other in side-by-side relation. In FIG. 9, non-bonded 
portions 30 of the film 14 are arranged in a grid or checkerboard pattern. 
Thus, bonded portions of the film 14 are confined to spaced square areas 
wherein the bonded portions are disposed adjacent to each other. The 
modifications illustrated in and 9 are advantageous in that the metal 
network 12 is entirely covered with the film 14, but can be taken out 
easily by tearing the non-bonded film portions 29,30 before its wires are 
twisted together or around nails or other retainers on the ducts, pipes, 
and building walls. 
Although the present invention has been shown and described in connection 
with its preferred embodiments, it should be understood that various 
changes and modifications may be made without departing from the scope of 
the appended claims.