Compositions – Preservative agents – Anti-caking – separative or protective coatings or zones
Reexamination Certificate
2000-06-09
2003-06-24
Warden, Jill (Department: 1743)
Compositions
Preservative agents
Anti-caking, separative or protective coatings or zones
C422S028000, C424S076800, C514S389000
Reexamination Certificate
active
06582627
ABSTRACT:
BACKGROUND OF THE INVENTION
The need for effective and economical preservative compositions is well known. There are a wide variety of applications where inhibiting the growth of microorganisms is necessary, as for example personal care products such as shampoos, creams, lotions, cosmetics, soap and household products such as laundry detergents, hard surface cleaners, and fabric softeners. The shelf life of these preparations depends on their resistance to microbial spoilage.
In addition, in many industrial applications, antimicrobial agents are useful in paint, wood, textiles, adhesives, sealants, leather, rope, paper pulp, plastics, fuel, oil, and rubber and metal working fluids. The control of slime-producing bacteria and fungi in pulp and paper mills and cooling towers is a matter of substantial commercial importance.
For the foregoing applications the demand for stable broad-spectrum preservatives has increased. In recent years, these needs have been met with solid formulations. For example, combinations of formaldehyde donors (e.g., dimethylol-dimethylhydantoin (DMDMH)) and halopropynyl compounds (e.g., 3-iodo-2-propynyl-butyl carbamate (IPBC)) have achieved considerable commercial success. Such synergistic combinations have been described in U.S. Pat. No. 4,844,991.
Furthermore, because of the demand of governmental regulations, low free-formaldehyde products are needed. Research in this area has also proved beneficial. For example, in the case of DMDMH, improved formulation and processing has resulted in compositions which contain less than 0. 1% free formaldehyde. (See U.S. Pat. No. 5,405,862.) In contrast, earlier formulations of DMDMH had over 1% of free formaldehyde. (See U.S. Pat. No. 3,987,184.)
At the present time, in addition to meeting the above criteria, the industry is demanding liquid forms of preservatives as the use of automatic liquid blending systems becomes more popular. Unfortunately, preservatives that are in liquid form, highly stable, broad spectrum, and low in free formaldehyde have eluded formulators.
SUMMARY OF THE INVENTION
It has now been discovered that highly stable, liquid formulations of broad spectrum preservatives can be prepared by admixing alkanol-substituted dimethylhydantoins, iodopropynyl compounds, stabilizers, and a solvent. This invention is based, in part, on the unexpected finding that the iodopropynyl compounds can be stabilized at high temperatures by the addition of hydantoin-type stabilizers such as dimethylhydantoin. Furthermore, the compositions of the invention have surprisingly good physical stability at low temperatures and enhanced solubility which allows the easy preparation of these highly concentrated mixtures. Such highly concentrated preservatives useful in automatic liquid blending systems could not heretofore be, prepared.
REFERENCES:
patent: 3987184 (1976-10-01), Foelsch
patent: 4163797 (1979-08-01), Burk et al.
patent: 4172140 (1979-10-01), Shull et al.
patent: 4844891 (1989-07-01), Rosen et al.
patent: 5073570 (1991-12-01), Tseng
patent: 5346913 (1994-09-01), Hsu et al.
patent: 5405862 (1995-04-01), Farina et al.
patent: 5428050 (1995-06-01), Merianos
patent: 5496842 (1996-03-01), Merianos
patent: 5552425 (1996-09-01), Merianos
patent: 5631273 (1997-05-01), Merianos
patent: 5965594 (1999-10-01), Schoenberg et al.
Ban Susan Alcorn
Farina Thomas Edward
Lutz Patrick Jay
Cross LaToya
Darby & Darby
Lonza Inc.
Warden Jill
LandOfFree
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