WO2002002475A1

WO2002002475A1 - Sprayable fiberglass insulation

Info

Publication number: WO2002002475A1
Application number: PCT/US2001/020003
Authority: WO
Inventors: Ralph D. Mcgrath; Jocelyn M. Seng; Neil R. Hettler
Original assignee: Owens Corning
Priority date: 2000-06-30
Filing date: 2001-06-22
Publication date: 2002-01-10
Also published as: AU2001271392A1

Abstract

A type of (and method of making/spraying) sprayable fiberglass insulation is disclosed. Such sprayable insulation comprises: nodulated glass fibers containing glass fibers coated with polyacrylic glycerol (PAG) binder; and an adhesive to adhere the nodulated glass fibers together and to adhere the PAG binder on the glass fibers to a surface against which the sprayable glass insulation is sprayed. Optionally, such sprayable insulation can include a coloring agent and/or a biocide that adhere to said PAG binder. Such insulation can be applied by: combining the nodulated glass fibers and the adhesive into a composite stream; and spraying the composite stream onto a surface. The adhesive in the composite stream adheres the nodulated glass fibers together and adheres the PAG binder on the glass fibers to the surface against which the sprayable glass insulation is sprayed so as to form an insulation layer.

Description

SPRAYABLE FIBERGLASS INSULATION

FIELD OF THE INVENTION

The invention is generally directed to fiberglass insulation, and more particularly to sprayable fiberglass insulation, and more particularly to sprayable, polyacrylic glycol (PAG)-bindered fiberglass insulation.

BACKGROUND OF THE INVENTION

Fiberglass insulation in the form of a batt, a board or molding media, includes glass fibers and a binder. Typically, the binder is phenolic. Though relatively inexpensive and though it cures to form a rigid thermoset polymeric matrix, phenolic binder has some problems. It is not low in odor. And, it causes the batt, board or molding media to appear to be yellow.

Phenolic binder binds the glass fibers by agglomeration, that is, by sticking to glass fibers only where any two glass fibers come into contact with each other. This is very different than coating each fiber in its entirety such that the coating on one fiber adheres to the coating on another fiber. Coloring agents do not adhere well to phenolic binder. And to the extent that a coloring agent adheres, it is present on only a small portion of the glass fiber, thus diluting the effect of the coloring agent. In some circumstances the fiberglass insulation is exposed, that is, not concealed behind wallboard inside a stud wall cavity. Such a circumstance can be a system in which the board or molding media forms of the fiberglass insulation is attached to a wall to help tune the sound of a room. In such an exposed insulation situation, the default yellow color of phenolic-bindered insulation can clash with the decoration in the room. And phenolic- hindered insulation hides dirt poorly.

In the exposed circumstance, typical phenolic-bindered fiberglass insulation can be made to appear to have a non-yellow color in one of three ways. First, a colorable facing (of paper and/or foil) can be applied to the insulation. Second, the surface can be coated with a paint sufficiently thick that it acoustically "blinds" the insulation, hi other words, the paint is viscous enough and is applied heavily enough that, in effect, a facing of paint is formed that closes all the interstices of the insulation. But this comprises the acoustic properties of the insulation because it changes the permeability of the insulation to air. Lastly, third, an inorganic coloring agent can be applied to the agglomerations, which produces a diffused color in combination with the clear glass fibers that are only covered at the points of agglomeration.

A colorable form of fiberglass insulation is known. It uses PAG as a binder. Such insulation appears white in color. It is low in odor, which makes it desirable for high temperature applications, such as in an oven. As disadvantage of PAG binder is that it is about twice as expensive as phenolic binder.

Easily colorable insulation is available in the form of cellulose. Cellulose is a wood fiber insulation. The wood fibers can be colored. Cellulose further has the advantage that it can be applied by spraying it. But cellulose has the disadvantages that it is flammable and it tends to mold.

Sprayable fiberglass insulation is known. But this typically uses an inorganic binder that is not easily colorable.

SUMMARY OF THE INVENTION The invention, in part, is a recognition that PAG binder performs well as a binder for sprayed fiberglass insulation.

The invention, in part, is a recognition that PAG binder coats each glass fiber substantially in its entirety, such that the coating on one fiber adheres to the coating on another fiber, unlike the agglomeration of the background art. The invention, also in part, is a recognition that sprayable adhesives adhere well to

PAG-binder.

The invention, also in part, is a recognition that coloring agents adhere well to

PAG-binder.

The invention, also in part, is a recognition that because the PAG binder coats each glass fiber substantially in its entirety, the coloring agent adhered to the PAG binder coats each glass fiber substantially in its entirety. To borrow a concept from the painting art, in effect, the PAG binder acts as a primer to prepare the whole glass fiber to be coated with the desired coloring agent. This produces a strong color in PAG-bindered fiberglass insulation. The invention, also in part, is a recognition that biocide adheres well to PAG binder, with or without a coloring agent being present on the PAG binder.

The invention, in part, provides sprayable fiberglass insulation comprising: nodulated glass fibers formed of glass fibers coated with PAG binder; and an adhesive to adhere said nodulated glass fibers together and adhere said PAG binder on said glass fibers to a surface against which said sprayable glass insulation is sprayed.

The invention, also in part, provides a method of making, that is, spraying, such an insulation product. Such a method comprises: combining into a composite stream components including nodulated glass fibers (that contain glass fibers coated with PAG binder), and an adhesive. The adhesive adheres said nodulated glass fibers together and adheres said PAG binder on said glass fibers to a surface against which said sprayable glass insulation is sprayed; and spraying said composite stream onto a surface, said adhesive in said composite stream adhering said nodulated glass fibers together and adhering said PAG binder on said glass fibers to said surface against which said sprayable glass insulation is sprayed so as to form an insulation layer.

Advantages of the present invention will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention, in part, provides sprayable fiberglass insulation comprising: glass fibers; a PAG binder to coat said glass fibers; and an adhesive to adhere said PAG binder to a surface against which said sprayable glass fiber insulation is sprayed. Such binders are known for use in connection with fiberglass insulation. Examples of such binder technology are the following U.S. Patent Nos. 5,661,113 to Arkens et al.; 5,340,868 to Strauss et al.; and 5,318,990 to Strauss.

Generally, the formation of glass fibers and fibrous glass insulation is known, for example, see U.S. Patent No. 5,340,868 to Strauss et al. Further, it is known to break up or nodulate such fibrous glass insulation into glass fiber nodules. Again, the known fibrous glass nodules are not easily colored, as described above for the Background Art. It is generally well-known in the art to fiberize molten glass. Glass is melted in a tank and supplied to a fiber-forming device such as a spinner or a bushing. Fibers of glass are attenuated from the device and are blown generally downwardly within a forming chamber. The glass fibers typically have a diameter from about 2 to about 9 microns and have a length from about .25 inch (.635 cm) to about 3 inches (7.62 cm). Preferably, the glass fibers range in diameter from about 3 to about 6 microns, and have a length from about .50 inch (1.27 cm) to about 1.50 inches (3.81 cm). The glass fibers are deposited onto a perforated, endless forming conveyor. The binder is applied to the glass fibers as they are being formed by suitable spray applicators so as to result in a distribution of the binder throughout the formed batt of fibrous glass. The glass fibers, having the uncured resinous binder adhered thereto (agglomerated in the case of the Background Art phenolic binder), are gathered and formed into a batt on the endless conveyor within the forming chamber with the aid of a vacuum drawn through the batt from below the forming conveyor. The residual heat contained in the glass fibers as well as the air flow through the batt causes a majority of the water to volatilize from the batt before it exits the forming chamber.

As the high-solids resin-coated fibrous glass batt emerges from the forming chamber, it expands vertically due to the resiliency of the glass fibers. The expanded batt is then conveyed to and through a curing oven. In the curing oven, heated air is passed through the insulation product to cure the resin. Also in the curing oven, the insulation product is compressed to form it into a blanket, batt or board. Flights/rollers above and below the batt slightly compress the batt. to give the finished product a predetermined thickness and surface finish. Typically, the curing oven is operated at a temperature from about 200°C (392°F) to about 325°C (617°F). Preferably, the temperature ranges from about 250°C (482°F) to about 300°C (572°F). Generally, the batt resides within the oven for a period of time from about 1/2 minute to about 3 minutes. For the manufacture of known thermal or acoustical insulation products, the time ranges from about 3/4 minute to about 11/2 minutes. The fibrous glass having a cured, rigid binder matrix emerges from the oven in the form of a batt. Again, it is known to nodulate such a batt into glass fiber nodules.

As mentioned in the discussion above of the Background Art, it is also generally known to spray either glass fiber or cellulose insulation. Examples of such technology include U.S. Patent Nos.: 5,947,646 to Lytle; 5,921,055 to Romes et al.; 4,648,920 to Sperber; 4,530,468 to Sperber; 4,487,365 to Sperber; 4,978,252 to Sperber; and 5,421,922 to Sperber. Commercially available examples of such technology include the FIBEPJFFIC brand, Model No. LNSUL8-2000 of blower marketed by Fiberiffic Energy Systems, a division of the Abiff Mfg. Corp., and the Fibreking Series 300 models of spray fiber machines marketed by the Fibreking Company.

An important aspect of the invention is to substitute PAG binder for the phenolic binder of the Background Art. This is done by piping PAG binder into the known fiber- forming devices instead of the phenolic binder.

Thus, the PAG-bindered glass fiber batt would be formed by: applying the water- carried PAG binder to glass fibers as they are being produced and formed into a batt; heating the batt so that water is volatilized from the binder; and further heating the high- solids binder-coated fibrous glass batt to cure the binder and thereby produce a finished fibrous glass batt. Then, the PAG-bindered batt is nodulized to form PAG-bindered glass fiber nodules. Such PAG-bindered nodules are pumped (pneumatically or hydraulically) into the known fiber-spraying device.

A optional aspect of the invention is to include a coloring agent component in the mixture of materials sprayed onto the to-be-insulated surface. The coloring agent can be pumped (pneumatically or hydraulically) into the known fiber-spraying device. Examples of PAG-binder-compatible coloring agents are: carbon black pigment; Nigrosine brand of black dye; and Vat Red brand of red dye.

For external application of the sprayed-on insulation where it is visible, darker colors are preferred because they hide dirt better than the yellow, phenolic-bindered fiberglass batt insulation of the Background Art or the white batt that results from not adding a coloring agent to a PAG-bindered sprayed-on insulation.

A further (and preferred) alternative for adding a coloring agent to the batt is to apply the coloring agent after the sprayable insulation has been sprayed-on to the to-be- insulated surface. In other words, the coloring agent is not added as the insulation is being sprayed-on. Rather, once the insulation has been sprayed-on to the to-be-insulated surface, then the coloring agent can be applied by again spraying the sprayed-on insulation. This is referred to as a post-installation technique.

The post-installation technique typically produces only a skin layer that is colored because the sprayed-on coloring agent need not, and may not be able to, completely penetrate the already sprayed-on insulation. This has the additional advantage of minimizing the quantity of coloring agent needed to give the impression of a colored batt (or board or molding media). Care should be taken to not blind the batt, that is, to not have the coloring agent be so viscous and so thickly applied that it fills the interstices of the batt. This would damage the acoustic properties of the batt.

Another optional aspect of the invention is to include a biocide component in the mixture of materials sprayed onto the to-be-insulated surface. The biocide can be mixed with the PAG binder or pumped (pneumatically or hydraulically) into the known fiber- spraying device.. Examples of PAG-binder-compatible biocides are silver zeolyte, KATHON brand of biocide marketed by the Rohm & Haas Company, AMICAL 48 brand of biocide marketed by the Angus Chemical Company, and HEALTHSHIELD brand of biocide marketed by Healthshield Technologies, LLC. A further (less preferred) alternative for adding the biocide to the batt is to apply the biocide after the sprayable insulation has been sprayed-on to the to-be-insulated surface. In other words, the biocide is not added as the insulation is being sprayed-on. Rather, once the insulation has been sprayed-on to the to-be-insulated surface, then the biocide can be applied by again spraying the sprayed-on insulation. This is referred to as a post-installation technique.

A disadvantage of the post-installation technique is that it only creates a skin layer that is protected with biocide because the sprayed-on biocide cannot completely penetrate the installed batt. Care should be taken to not blind the batt, that is, to not have the biocide be so viscous and so thickly applied that it fills the interstices of the batt. This would damage the acoustic properties of the batt.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

Claims

WHAT IS CLAIMED IS:

1. Sprayable glass fiber insulation comprising a mixture of: nodulated glass fibers containing glass fibers coated with polyacrylic glycerol (PAG) binder; and an adhesive to adhere said nodulated glass fibers together and to adhere said PAG binder on said glass fibers to a surface against which said sprayable glass insulation is sprayed.

2. The sprayable glass fiber insulation of claim 1, further comprising a coloring agent adhered to said PAG binder.

3. The sprayable glass fiber insulation of claim 1, wherein said coloring agent on said PAG binder is perceived as being non-white and non-yellow.

4. The sprayable glass fiber insulation of claim 3, wherein said coloring agent on said PAG binder is perceived as being black.

5. The sprayable glass fiber insulation of claim 1, wherein said insulation further comprises a biocide.

6. The sprayable glass fiber insulation of claim 5, wherein said biocide is silver zeolyte.

7. A method of applying sprayable glass fiber insulation comprising: combining into a composite stream components including nodulated glass fibers containing glass fibers coated with polyacrylic glycerol (PAG) binder, and an adhesive to adhere said nodulated glass fibers together and to adhere said PAG binder on said glass fibers to a surface against which said sprayable glass insulation is sprayed; and spraying said composite stream onto a surface, said adhesive in said composite stream adhering said nodulated glass fibers together and adhering said PAG binder on said glass fibers to said surface against which said sprayable glass insulation is sprayed so as to form an insulation layer.

8. The method of claim 7, wherein said composite stream includes a coloring agent that can adhere to said PAG binder.

9. The method of claim 8, wherein said coloring agent on said PAG binder is perceived as being non-white and non-yellow.

10. The method of claim 9, wherein said coloring agent on said PAG binder is perceived as being black.

11. The method of claim 7, wherein said composite stream further comprises a biocide that can adhere to said PAG binder.

12. The method of claim 11, wherein said biocide is silver zeolyte.

13. The method of claim 7, further comprising: spraying a coloring agent onto said insulation layer.

14. The method of claim 13, wherein said coloring agent on said PAG binder is perceived as being non-white and non-yellow.

15. The method of claim 14, wherein said coloring agent on said PAG binder is perceived as being black.

16. The method of claim 7, further comprising: spraying a biocide onto insulation layer.

17. The method of claim 16, wherein said biocide is silver zeolyte.

18. The method of claim 7, further comprising: forming separate tributary streams of said nodulated glass fibers and said adhesive, respectively, and; aiming said tributary streams so as to combine said tributary streams into said composite stream.