This disclosure relates to reflective insulation and related methods of making reflective insulation.
Zupon et al. U.S. Pat. 6,797,356 discloses a reflective insulation. A schematic representation of the manufacture of the Zupon et al. reflective insulation is shown in
The Zupon et al. reflective insulation includes a reflective layer A (which reflective layer may be formed from aluminum), an insulation layer B formed of fiberglass, and a vapor barrier layer C (which vapor barrier layer may be formed from plastic or a reflective material such as the aluminum).
A first side of the fiberglass layer B is bonded to the reflective layer A by a deposit of hot melt glue D. A second side of the fiberglass layer is bonded to the vapor barrier layer by a second deposit of hot melt glue E. During manufacture, the hot melt glue is applied in liquid form directly to the opposite sides of the fiberglass layer, and the reflective layer and vapor barrier layers are then placed onto the sides of the fiberglass over the liquid hot melt glue. The laminated product passes between rollers that compress the laminations for intimate contact of the wet, liquid glue and the lamination layers.
Although the Zupon et al. insulation generally works well in suitable applications, it has been found that the wet glue adhesive does not always provide adhesion over the entire area of lamination. It is theorized that gaps or inconsistencies in the application of the hot melt glue onto the fiberglass results in gaps or unadhered areas between the fiberglass and the reflective layer or vapor barrier of the finished product. Because the reflective and vapor barrier layers must be placed over the fiberglass immediately after the hot melt glue is applied, it can be difficult to inspect for or otherwise assure uniform, satisfactory coverage and adhesion of the glue with the laminations.
Disclosed is a reflective insulation that has a laminated structure that includes a reflective layer, an insulation layer such as a fiberglass layer, and a vapor layer or alternatively a second reflective layer. The vapor layer may also be a reflective layer. The layers adhere to each other using a heat seal film that is preferably activated using flame lamination.
A heat seal film is typically a thermoplastic film that is applied onto a substrate surface and later activated by heat to become adhesive and thereby form an adhesive film that can adhere to another surface. In possible embodiments, heat can be applied by flame lamination. Flame lamination is a process wherein a material such as a heat seal film is passed over a flame to create a thin layer of melted or otherwise tacky material that acts as an adhesive material. The adhesive material is then brought into contact with the material forming the adjacent layer of a laminate under pressure to develop a bond between the two surfaces.
The disclosed reflective insulation has a number of advantages. Because a heat seal film is being used, the film can be applied to a side of a material forming one of the laminations well before the reflective insulation is made. Thus qualify control of the resulting adhesion layer is better controlled to assure satisfactory adhesion between laminations over the entire product.
In addition, flame lamination of a heat seal film results in an improved adhesion layer with less likelihood of later separation lamination layers and with greater mechanical strength as compared to the use of hot melt glue. Thus the reliability of the reflective insulation is improved.
Furthermore, by using a heat film that is attached to the outer reflective lamination layers prior to manufacture, the insulation layer can be formed from organic insulation instead of fiberglass.
Other objects and features of the disclosure will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawing sheets.
An activated heat seal film 18 is shown separate from and between the first reflective layer 12 and the insulation layer 16, and an activated heat seal film 20 is shown separate from and between the second reflective layer 14 and the insulation layer 16. The activated heat seal film layers 18, 20 contacts the reflective layers 12, 14 respectively and the respective opposite sides of the insulation layer 16, adhering the reflective layers 12, 14 to the insulation layer 16. In the illustrated embodiment the heat seal films are activated by flame lamination as will be described in further detail below.
In possible embodiments of the disclosed reflective insulation, aluminum film that will form part of the reflection layer 12 or reflector layer 14 defines or forms a substrate that is provided with the heat seal film to form an integral material prior forming part of the reflective insulation 10. The heat seal film is preapplied as a backing to one side of the aluminum film substrate. Such an integral heat seal film/aluminum film material is commercially available from the Johns-Manville Corporation, of Denver, Colorado USA. The heat seal film adhering to the aluminum film substrate is then activated when manufacturing the reflective insulation 10 to adhere the aluminum film to the insulation.
If desired in alternative embodiments, a reflective layer 12 and/or a reflective layer 14 can be formed as a conventional perforated layer having perforations (not shown). The perforations enable air to escape from between the reflective layer and the insulation layer during manufacture of the reflective insulation.
In other possible embodiments, the reflective layer 14 can be formed from a polyester or polyethylene material. The polyester or polyethylene in possible embodiments may also be flame laminated to the insulation during manufacture of the reflective insulation 10.
In yet other possible embodiments, the reflective layer 14 can be replaced with a vapor barrier or can itself form a vapor barrier. The vapor barrier can be formed from a polyester or polyethylene material. The polyester or polyethylene in possible embodiments may be adhered to the insulation by an activated heat seal film or, in other possible embodiments, the polyester or polyethylene may itself be flame laminated directly to the insulation during manufacture of the reflective insulation 10.
The flame laminator machine heats the heat seal film on the aluminum films until the film is tacky or otherwise in condition for application as an adhesive. After being heated, the films are pressed against the opposite sides of the fiberglass to adhere the heat seal films and thereby the aluminum film against the fiberglass. The resulting laminated reflective insulation 118 is rolled onto a roller for later processing.
While this disclosure includes one or more illustrative embodiments described in detail, it is understood that the one or more embodiments are each capable of modification and that the scope of this disclosure is not limited to the precise details set forth herein but include such modifications that would be obvious to a person of ordinary skill in the relevant art, as well as such changes and alterations that fall within the purview of the following claims.
This application is a division of and claims priority to and the benefit of the filing date of U.S. Pat. Application Serial No. 14/772,083 “Reflective Insulation” filed Sep. 2, 2015 at Attorney’s Docket No. 1-1803-US and pending on the filing date of this patent application, which in turn claimed priority to and the benefit of the filing date of now expired PCT Patent Application Serial No. PCT/US14/18824 “Reflective Insulation” filed Feb. 27, 2014 at Attorney’s Docket No. 1-1803-PCT, which in turn claimed priority to and the benefit of the filing date of now expired U.S. Provisional Pat. Application Serial No. 61/772,013 “Reflective Insulation” filed Mar. 4, 2013 at Attorney’s Docket No. 1-1803-P.
Number | Date | Country | |
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61772013 | Mar 2013 | US |
Number | Date | Country | |
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Parent | 14772083 | Sep 2015 | US |
Child | 18205198 | US |