Antifungal paints and coatings

Abstract

Antifungal and antibacterial peptides, polypeptides and proteins as antifungal additives for paint and other coatings are disclosed, along with antifungal compositions, and coated surfaces with antifungal properties. Methods of using the coatings for treating and/or inhibiting growth of mold, mildew and other fungi and bacteria on objects such as building materials that are susceptible to such infestation are also disclosed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 60 / 485,234 filed Jul. 3, 2003, the disclosure of which is hereby incorporated herein in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not applicable BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The present invention generally relates to antifungal and antibacterial compositions and methods employing such compositions to deter or prevent fungal growth in stored coatings and on susceptible surfaces. More particularly, the present invention relates to such compositions containing antifungal and antibacterial peptides, polypeptides or proteins and to methods of making and using such compositions. [0005] 2. Description of the Related Art [0006] Fungal growth on indoor and outdoor surfaces is a major environmental concern today affecting home, work and recreational environments. N...

AI Technical Summary

Benefits of technology

[0018] The compositions and methods of the present invention overcome some of the disadvantages of previous antifungal or fungus-resistant paints, coatings and other compositions such as elastomers, textile finishes, adhesives, and sealants. It was not previously known to combine a natural, synthetic or recombinant antifungal peptide, polypeptide or peptide with a paint or other coating material to provide a coated surface with sustainable antifungal activity that protects the recipient surface from fungal infestation and defacement, and which also provides fungus resistance to the composition itself. It is now disclosed that antifungal peptidic agents offer a new tool in the arsenal of fungicidal and fungistatic chemicals. Accordingly, new antifungal and antibacterial paints, coatings, films and other compositions are provided which contain one or more bioactive peptides, polypeptides and / or proteins as antifungal and antibacterial peptidic agents. Methods of using the antifungal and antibacterial additives and compositions for treating existing fungal or bacterial colonies and / or for deterring or preventing fungal or bacterial infestations and inhibiting cell growth or proliferation on a variety of inanimate objects such as interior and exterior architectural surfaces and building materials are also provided. The compositions and methods disclosed herein avoid many of the drawbacks of existing methods and compositions which rely on non-specific chemical bacteriocides, fungicides, or antifungal agents. By application of a protective coating comprising one or more antifungal or antibacterial protein, polypeptide or peptide, one can prevent or deter or lessen the infestation and growth of fungus or bacterium. At the same time, the associated discoloration, disfiguration and / or degradation of the supporting substrate or surface can be avoided or reduced. The compositions of the invention are especially useful on surfaces where conditions are conducive to deposition and development of fungus or bacteria, and where control of fungal or bacterial growth is preferably accomplished with compositions which are not toxic to humans, pets and other animals or harmful to the environment.

Problems solved by technology

Not only can fungus (e.g., mold, mildew) be unsightly on exposed surfaces, it can destroy wood, fiber and other materials if left untreated, causing severe damage to buildings and other structures and equipment.

Over the past few years it has become increasingly apparent that exposure to certain fungi or their spores can seriously impact the health of humans, pets and other animals.

Although fungi are certainly not the only factors that detrimentally affect indoor air quality, in many instances they have been identified as a primary contributor to indoor air quality problems.

Of particular concern are the pathogenic fungi, which can cause significant harm to individuals who are exposed to them.

About 300 species are presently known to be pathogenic for man, but it is thought that there are many other as yet unrecognized fungal pathogens.

Today, an especially problematic fungal genus sometimes found in buildings that have excess indoor moisture is Stachybotrys.

Depending on the particular conditions of temperature, pH and humidity in which the mold is growing, Stachybotrys may produce mycotoxins, compounds that have toxic properties.

The moist indoor environment which promotes growth of these fungi can arise from water damage, excessive humidity, water leaks, condensation, water infiltration, or flooding, in some cases due to defects in building construction, faulty mechanical system design, and / or operational problems.

Modern homes tend to be less well ventilated, and although the use of air conditioning reduces humidity making it harder for mold to grow, today's central air conditioning systems can also facilitate the spread of mold spores throughout a home.

Vulnerable structures and materials that are difficult to access for cleaning, or for which cleaning is neglected, are particularly vulnerable to attack by fungi.

Fungi are also known to contaminate stored paints, fuels, and many other industrial products.

According to the U.S. Environmental Protection Agency, there is no practical way to eliminate all mold and mold spores in the indoor environment.

As mentioned above, paints and paint films or coatings are known to be vulnerable to mold contamination due to the presence of common organic components that act as cellulosic thickeners, surfactants and defoamers, and which can also serve as a source of food for fungus cells.

Fungi can also discolor and reduce the viscosity of the paint, and produce foul odors.

In practice, however, the antifungal properties of most coating compositions in use today persist for variable lengths of time, depending on the amount of exposure to the elements, abrasion and erosion.

Most antifungal chemicals are non-specific as to the organism affected and can be detrimental to the environment, including toxicity to plant and animal life.

It is more difficult to identify fungus-specific agents than it is to discover bacteria specific-agents because fungal cells share many similarities with the cells of higher organisms, whereas bacterial cells are distinctly different.

Since most of the known naturally occurring antifungal agents are poorly characterized at best, the persistence and toxicity of such compounds in the environment is also unknown.

Furthermore, the fact that many of those compounds are produced by microbes in the environment suggests that they may have a limited spectrum of antifungal activity.

A drawback of most of the antifungal agents in use today is that they are as toxic to higher organisms as they are to the target fungi.

The more target-specific antifungal agents tend to be very rare and / or costly.

Although significant advancement has been made in identifying various chemical agents and natural and synthetic peptides or proteins that demonstrate antifungal activity for certain uses (e.g., medical treatment or agricultural use), there is no indication that any such biomolecule could be used successfully in paints or other coating materials for protecting or treating non-living objects.