U.S. patent application number 13/863001 was filed with the patent office on 2014-10-16 for peroxycarboxylic acid based sanitizing rinse additives for use in ware washing.
This patent application is currently assigned to ECOLAB USA INC.. The applicant listed for this patent is ECOLAB USA INC.. Invention is credited to Allison Brewster, Steven J. Lange, Junzhong Li, Richard Staub, Xin Sun.
Application Number | 20140308162 13/863001 |
Document ID | / |
Family ID | 51686928 |
Filed Date | 2014-10-16 |
United States Patent
Application |
20140308162 |
Kind Code |
A1 |
Lange; Steven J. ; et
al. |
October 16, 2014 |
PEROXYCARBOXYLIC ACID BASED SANITIZING RINSE ADDITIVES FOR USE IN
WARE WASHING
Abstract
A concentrated liquid sanitizing and rinse composition
containing peroxycarboxylic acid(s) and compatible rinse aid
surfactants is disclosed. The sanitizing and rinsing compositions
are formulated in a single liquid concentrate, replacing a
traditional dual product of a sanitizer and rinse aid. The
sanitizing and rinsing chemistries are particularly effective at
neutral pHs against gram negative organisms at elevated
temperatures. Methods of using the concentrated liquid sanitizing
and rinse composition are also disclosed.
Inventors: |
Lange; Steven J.; (St. Paul,
MN) ; Li; Junzhong; (Apple Valley, MN) ; Sun;
Xin; (Eagan, MN) ; Brewster; Allison; (Eagan,
MN) ; Staub; Richard; (Lakeville, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ECOLAB USA INC. |
St. Paul |
MN |
US |
|
|
Assignee: |
ECOLAB USA INC.
St. Paul
MN
|
Family ID: |
51686928 |
Appl. No.: |
13/863001 |
Filed: |
April 15, 2013 |
Current U.S.
Class: |
422/34 ;
424/616 |
Current CPC
Class: |
A61L 2/18 20130101; A01N
59/00 20130101; A01N 37/02 20130101; A01N 37/16 20130101; A01N
37/16 20130101; A01N 37/02 20130101; A01N 25/30 20130101; A01N
25/30 20130101; A01N 25/30 20130101; A01N 37/16 20130101; A01N
37/02 20130101; A01N 37/02 20130101; A01N 59/00 20130101; A61L
2/186 20130101 |
Class at
Publication: |
422/34 ;
424/616 |
International
Class: |
A61L 2/18 20060101
A61L002/18 |
Claims
1. A sanitizing rinse additive composition comprising: a
C.sub.1-C.sub.22 peroxycarboxylic acid; a C.sub.1-C.sub.22
carboxylic acid; hydrogen peroxide; and a nonionic defoaming and
wetting surfactant(s); wherein the composition is a low odor
concentrate having less than about 2 wt-% peroxyacetic and peracid
acid, and wherein the composition when diluted from about 0.01%
weight/volume to about 2% weight/volume provides at least a 5 log
reduction in pathogenic organisms at a temperature of at least
about 100.degree. F.
2. The composition of claim 1, wherein the nonionic defoaming
surfactant is an alkyl-ethylene oxide-propylene oxide copolymer
surfactant and wherein the nonionic wetting surfactant is an
alcohol ethoxylate according to the following structure
R--O--(CH.sub.2CH.sub.2O).sub.n--H, wherein R is a C.sub.1-C.sub.12
alkyl group and n is an integer in the range of 1 to 100.
3. The composition of claim 2, wherein the alkyl-ethylene
oxide-propylene oxide copolymer surfactant has a single hydroxyl
functional group per molecule according to the following structure
Alkyl-(EO)m-(PO)n-POH, wherein m is an integer in the range from 1
to 20 and n is an integer in the range from 1 to 20.
4. The composition of claim 1, wherein the ratio of the nonionic
defoaming surfactant to the nonionic wetting surfactant is from
about 1.5:1 to about 10:1
5. The composition of claim 1, wherein the C.sub.1-C.sub.22
peroxycarboxylic acid is a C.sub.2-C.sub.20 peroxycarboxylic acid
and wherein the C.sub.1-C.sub.22 carboxylic acid is a
C.sub.2-C.sub.20 carboxylic acid.
6. The composition of claim 1, further comprising at least one
additional agent selected from the group consisting of a hydrotrope
or coupling agent, a solvent, a stabilizing agent and combinations
thereof.
7. The composition of claim 1, wherein the C.sub.1-C.sub.22
peroxycarboxylic acid comprises from about 1 wt-% to about 40 wt-%,
the C.sub.1-C.sub.22 carboxylic acid comprises from about 1 wt-% to
about 80 wt-%, the hydrogen peroxide comprises from about 1 wt-% to
about 80 wt-%, and the nonionic surfactants comprise from about 1
wt-% to about 50 wt-% of the composition.
8. The composition of claim 1, wherein the composition when diluted
from about 0.01% weight/volume to about 0.05% weight/volume
provides at least a 5 log reduction in pathogenic organisms in 30
seconds or less at a temperature of at least about 120.degree.
F.
9. The composition of claim 1, wherein peroxycarboxylic acid in the
concentrate contains less than about 1 wt-% peroxyacetic acid.
10. A concentrated sanitizing rinse additive composition
comprising: from about 1 wt-% to about 40 wt-% C.sub.1-C.sub.22
peroxycarboxylic acid; from about 1 wt-% to about 80 wt-%
C.sub.1-C.sub.22 carboxylic acid; from about 1 wt-% to about 75
wt-% hydrogen peroxide; from about 1 wt-% to about 25 wt-%
alkyl-ethylene oxide-propylene oxide type nonionic surfactant; and
from about 1 wt-% to about 20 wt-% alcohol ethoxylate nonionic
surfactant; wherein the concentrate composition has low odor, and
wherein the composition when diluted from about 0.01% weight/volume
to about 1% weight/volume provides at least a 5 log reduction in
pathogenic organisms at a temperature of at least about 100.degree.
F., and wherein the diluted composition has a pH of about 5 or
greater.
11. The composition of claim 10, wherein the C1-C22
peroxycarboxylic acid is a C2-C20 peroxycarboxylic acid selected
from the group consisting of peroxyacetic acid, peroxyoctanoic
acid, peroxysulfonated oleic acid and combinations thereof, wherein
the C1-C22 carboxylic acid is a C2-C20 carboxylic acid selected
from the group consisting of acetic acid, octanoic acid, sulfonated
oleic acid and combinations thereof, and wherein the composition
comprises less than about 2 wt-% peroxyacetic acid.
12. The composition of claim 10, wherein the nonionic defoaming
surfactant is an alkyl-ethylene oxide-propylene oxide copolymer
surfactant according to the following structure
Alkyl-(EO)m-(PO)n-POH, wherein m is an integer in the range from 1
to 20 and n is an integer in the range from 1 to 20, and wherein
the nonionic wetting surfactant is an alcohol ethoxylate according
to the following structure R--O--(CH.sub.2CH.sub.2O).sub.n--H,
wherein R is a C.sub.1-C.sub.12 alkyl group and n is an integer in
the range of 1 to 100.
13. The composition of claim 10, further comprising at least one
additional agent selected from the group consisting of a hydrotrope
or coupling agent, a solvent, a stabilizing agent and combinations
thereof.
14. The composition of claim 13, wherein the stabilizing agent is a
phosphate peroxycarboxylic acid stabilizer and/or dipicolinic acid
peroxycarboxylic acid stabilizer.
15. A method of sanitizing and rinsing comprising: providing a low
odor, liquid concentrate, equilibrium peroxycarboxylic acid
sanitizing rinse aid composition, wherein the composition
comprises: a C.sub.1-C.sub.22 peroxycarboxylic acid; a
C.sub.1-C.sub.22 carboxylic acid; hydrogen peroxide; an
alkyl-ethylene oxide-propylene oxide type nonionic surfactant; and
an alcohol ethoxylate nonionic surfactant; and sanitizing a surface
in need thereof without an additional rinsing step; wherein the
composition when diluted from about 0.01% weight/volume to about 1%
weight/volume provides at least a 5 log reduction in pathogenic
organisms at a temperature of at least about 100.degree. F.
16. The method of claim 15, wherein the composition is diluted from
about 0.01% weight/volume to about 0.2% weight/volume with a
diluent.
17. The method of claim 16, wherein the composition is diluted from
about 0.01% weight/volume to about 0.05% weight/volume with a
diluent.
18. The method of claim 16, wherein the sanitized surface is
spot-free and film-free.
19. The method of claim 18, wherein the sanitizing is a low or no
odor application of use.
20. The method of claim 15, wherein the utilities for a warewashing
machine employing the sanitizing are substantially similar to or
less than a low temperature ware wash machine employed for
chlorine-based sanitizing.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a concentrated liquid
sanitizing and rinse composition. In particular, peroxycarboxylic
acid sanitizing and rinsing compositions and methods for using the
compositions are disclosed. The sanitizing and rinsing compositions
are formulated in a single liquid concentrate, replacing a
traditional dual product of a sanitizer and rinse aid. The single
dual use formulation provides a sanitizing peroxycarboxylic acid
and a rinse aid surfactant(s) compatible with the sanitizing agent.
Methods of using the single dual use formulations can include in
aqueous solutions on articles including, for example, cookware,
dishware, flatware, glasses, cups, hard surfaces, glass surfaces,
etc. Surprising, certain embodiments of the sanitizing rinse aid
compositions are effective at essentially neutral pHs against gram
negative organisms at elevated temperatures.
BACKGROUND OF THE INVENTION
[0002] Mechanical warewashing machines including dishwashers have
been common in the institutional and household environments for
many years. Such automatic warewashing machines clean dishes using
two or more cycles which can include initially a wash cycle
followed by a rinse cycle. Such automatic warewashing machines can
also utilize other cycles, for example, a soak cycle, a pre-wash
cycle, a scrape cycle, additional wash cycles, additional rinse
cycles, a sanitizing cycle, and/or a drying cycle. Any of these
cycles can be repeated, if desired and additional cycles can be
used. Detergents and/or sanitizers are conventionally used in these
warewashing applications to provide cleaning, disinfecting and/or
sanitizing. Dishmachines can remove soil by using a combination of
various detergents and/or sanitizers, temperatures, and/or
mechanical action from water. In some aspects where a sanitizer is
not employed, water is heated to provide sanitization of the ware,
placing an increase utility demand on a ware wash machine.
[0003] In addition to detergents and sanitizers, rinse aids are
also conventionally used in warewashing applications to promote
drying and to prevent the formation of spots on the ware being
washed. In order to reduce the formation of spotting, rinse aids
have commonly been added to water to form an aqueous rinse that is
sprayed on the ware after cleaning is complete. A number of rinse
aids are currently known, each having certain advantages and
disadvantages, such as those disclosed in U.S. Pat. Nos. 3,592,774,
3,625,901, 3,941,713, 4,005,024, 4,187,121, 4,147,559, 4,624,713.
In addition, further disclosure of rinse additives including
nonionic surfactants is disclosed in Schick, "Nonionic
Surfactants", published by Marcel Dekker, and John L. Wilson, Soap
and Chemical Specialties, February 1958, pp. 48-52 and 170-171,
which is herein incorporated by reference in its entirety.
[0004] There remains an ongoing need for alternative rinse aid
compositions. There further remains an ongoing need for improved
efficacy of dishmachines, including maximizing the efficacy of the
combination of detergents, sanitizers and/or rinse aids
formulations. In addition, there is a desire among consumers, both
institutional and household, to reduce the utilities required for
operating such dishmachines. It is against this background that the
present disclosure is made to develop a combination sanitizing
agent and rinse aid into a single, stable formulation.
[0005] Accordingly, it is an objective of the claimed invention to
develop concentrated liquid compositions and methods of using the
same for warewashing applications to provide desired cleaning and
rinsing performance in a single, dual use formulation that
minimizes utilities consumed by such applications to that
equivalent to low temperature warewashing applications.
[0006] A further object of the invention is to provide a
non-chlorine based sanitizing system for warewashing and other
applications containing peroxycarboxylic acids with non-foaming
rinse additives.
[0007] A further object of the invention is to provide warewashing
applications that reduce energy consumption required for
warewashing methods similar to the energy consumption of low
temperature machines.
[0008] A still further object of the invention is to provide a
single dual formulation for both sanitizing and rinsing, thereby
reducing the overall chemistry consumption of the application of
use.
[0009] Other objects, advantages and features of the present
invention will become apparent from the following specification
taken in conjunction with the accompanying drawings.
BRIEF SUMMARY OF THE INVENTION
[0010] An advantage of the invention is the combination of a
peroxycarboxylic acid sanitizer chemistry with compatible rinse aid
surfactants into a single, stable liquid concentrate. Beneficially,
according to the embodiments of the invention, the liquid
concentrate provides a single dual use formulation to replace
conventional sanitizing and rinse aid formulations provided in
separate products. As a result, the claimed compositions and
methods of using the compositions result in significant benefits,
including: a decrease in utilities (e.g., energy and water) that is
expected from low temperature door dishwashing machines;
concentrated multi-part compositions including the sanitizing
agent, rinse additives and optional additional components in a dual
use composition; and enables use of lower voltage and amperage
dishmachine due to use of the peroxycarboxylic acid sanitizing
agents.
[0011] In an embodiment, the present invention discloses a
sanitizing rinse additive composition comprising: a C1-C22
peroxycarboxylic acid; a C1-C22 carboxylic acid; hydrogen peroxide;
and a nonionic defoaming and wetting surfactant(s). In an aspect of
the invention, the composition is a low odor peroxycarboxylic acid
composition. In a further aspect of the invention, the composition
when diluted from about 0.01% weight/volume to about 1%
weight/volume provides at least a 5 log reduction in pathogenic
organisms at a temperature of at least about 100.degree. F.
[0012] In a further embodiment, the present invention discloses a
sanitizing rinse additive composition comprising: from about 1 wt-%
to about 40 wt-% C.sub.1-C.sub.22 peroxycarboxylic acid; from about
1 wt-% to about 80 wt-% C.sub.1-C.sub.22 carboxylic acid; from
about 1 wt-% to about 80 wt-% hydrogen peroxide; from about 1 wt-%
to about 25 wt-% alkyl-ethylene oxide-propylene oxide type nonionic
surfactant; and from about 1 wt-% to about 20 wt-% alcohol
ethoxylate nonionic surfactant. In an aspect of the invention, the
composition is a low odor, liquid concentrate. In a further aspect,
the use solution of the liquid concentrate has a pH greater than
about 5. In a further aspect, the composition when diluted from
about 0.01% weight/volume to about 0.02% weight/volume provides at
least a 5 log reduction in pathogenic organisms at a temperature of
at least about 100.degree. F.
[0013] In a still further embodiment, the present invention
discloses a method of sanitizing and rinsing comprising: providing
a low odor, liquid concentrate, equilibrium peroxycarboxylic acid
sanitizing rinse aid composition, wherein the composition
comprises: a C.sub.1-C.sub.22 peroxycarboxylic acid; a
C.sub.1-C.sub.22 carboxylic acid; hydrogen peroxide; an
alkyl-ethylene oxide-propylene oxide type nonionic surfactant; and
an alcohol ethoxylate nonionic surfactant; and sanitizing a surface
in need thereof without an additional rinsing step. In a further
aspect, the composition when diluted from about 0.01% weight/volume
to about 1% weight/volume provides at least a 5 log reduction in
pathogenic organisms at a temperature of at least about 100.degree.
F.
[0014] While multiple embodiments are disclosed, still other
embodiments of the present invention will become apparent to those
skilled in the art from the following detailed description, which
shows and describes illustrative embodiments of the invention.
Accordingly, the drawings and detailed description are to be
regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows foam performance at 122.degree. F. after
storage at 104.degree. F. using the various surfactants
combinations according to embodiments of the invention.
[0016] FIGS. 2A-2B show image analysis data of film on glasses
(FIG. 2A) and plastic coupons (FIG. 2B) for sanitizing rinse
composition and for control samples set forth in the Examples
according to embodiments of the invention.
[0017] FIGS. 3A-3B show visual grading data of the glasses (FIG.
3A) and plastic coupons (FIG. 3B) for sanitizing rinse composition
and for control samples set forth in the Examples according to
embodiments of the invention.
[0018] Various embodiments of the present invention will be
described in detail with reference to the drawings, wherein like
reference numerals represent like parts throughout the several
views. Reference to various embodiments does not limit the scope of
the invention. Figures represented herein are not limitations to
the various embodiments according to the invention and are
presented for exemplary illustration of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] The embodiments of this invention are not limited to
particular sanitizing and rinsing compositions and methods of
employing the same, which can vary and are understood by skilled
artisans. It is further to be understood that all terminology used
herein is for the purpose of describing particular embodiments
only, and is not intended to be limiting in any manner or scope.
For example, as used in this specification and the appended claims,
the singular forms "a," "an" and "the" can include plural referents
unless the content clearly indicates otherwise. Further, all units,
prefixes, and symbols may be denoted in its SI accepted form.
[0020] Numeric ranges recited within the specification are
inclusive of the numbers defining the range and include each
integer within the defined range. Throughout this disclosure,
various aspects of this invention are presented in a range format.
It should be understood that the description in range format is
merely for convenience and brevity and should not be construed as
an inflexible limitation on the scope of the invention.
Accordingly, the description of a range should be considered to
have specifically disclosed all the possible sub-ranges as well as
individual numerical values within that range. For example,
description of a range such as from 1 to 6 should be considered to
have specifically disclosed sub-ranges such as from 1 to 3, from 1
to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as
well as individual numbers within that range, for example, 1, 2, 3,
4, 5, and 6. This applies regardless of the breadth of the
range.
[0021] So that the present invention may be more readily
understood, certain terms are first defined. Unless defined
otherwise, all technical and scientific terms used herein have the
same meaning as commonly understood by one of ordinary skill in the
art to which embodiments of the invention pertain. Many methods and
materials similar, modified, or equivalent to those described
herein can be used in the practice of the embodiments of the
present invention without undue experimentation, the preferred
materials and methods are described herein. In describing and
claiming the embodiments of the present invention, the following
terminology will be used in accordance with the definitions set out
below.
[0022] The term "about," as used herein, refers to variation in the
numerical quantity that can occur, for example, through typical
measuring and liquid handling procedures used for making
concentrates or use solutions in the real world; through
inadvertent error in these procedures; through differences in the
manufacture, source, or purity of the ingredients used to make the
compositions or carry out the methods; and the like. The term
"about" also encompasses amounts that differ due to different
equilibrium conditions for a composition resulting from a
particular initial mixture. Whether or not modified by the term
"about", the claims include equivalents to the quantities.
[0023] The term "actives" or "percent actives" or "percent by
weight actives" or "actives concentration" are used interchangeably
herein and refers to the concentration of those ingredients
involved in cleaning expressed as a percentage minus inert
ingredients such as water or salts.
[0024] As used herein, the term "alkyl" or "alkyl groups" refers to
saturated hydrocarbons having one or more carbon atoms, including
straight-chain alkyl groups (e.g., methyl, ethyl, propyl, butyl,
pentyl, hexyl, heptyl, octyl, nonyl, decyl, etc.), cyclic alkyl
groups (or "cycloalkyl" or "alicyclic" or "carbocyclic" groups)
(e.g., cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl,
cyclooctyl, etc.), branched-chain alkyl groups (e.g., isopropyl,
tert-butyl, sec-butyl, isobutyl, etc.), and alkyl-substituted alkyl
groups (e.g., alkyl-substituted cycloalkyl groups and
cycloalkyl-substituted alkyl groups).
[0025] Unless otherwise specified, the term "alkyl" includes both
"unsubstituted alkyls" and "substituted alkyls." As used herein,
the term "substituted alkyls" refers to alkyl groups having
substituents replacing one or more hydrogens on one or more carbons
of the hydrocarbon backbone. Such substituents may include, for
example, alkenyl, alkynyl, halogeno, hydroxyl, alkylcarbonyloxy,
arylcarbonyloxy, alkoxycarbonyloxy, aryloxy, aryloxycarbonyloxy,
carboxylate, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl,
aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl,
alkylthiocarbonyl, alkoxyl, phosphate, phosphonato, phosphinato,
cyano, amino (including alkyl amino, dialkylamino, arylamino,
diarylamino, and alkylarylamino), acylamino (including
alkylcarbonylamino, arylcarbonylamino, carbamoyl and ureido),
imino, sulfhydryl, alkylthio, arylthio, thiocarboxylate, sulfates,
alkylsulfinyl, sulfonates, sulfamoyl, sulfonamido, nitro,
trifluoromethyl, cyano, azido, heterocyclic, alkylaryl, or aromatic
(including hetero aromatic) groups.
[0026] In some embodiments, substituted alkyls can include a
heterocyclic group. As used herein, the term "heterocyclic group"
includes closed ring structures analogous to carbocyclic groups in
which one or more of the carbon atoms in the ring is an element
other than carbon, for example, nitrogen, sulfur or oxygen.
Heterocyclic groups may be saturated or unsaturated. Exemplary
heterocyclic groups include, but are not limited to, aziridine,
ethylene oxide (epoxides, oxiranes), thiirane (episulfides),
dioxirane, azetidine, oxetane, thietane, dioxetane, dithietane,
dithiete, azolidine, pyrrolidine, pyrroline, oxolane, dihydrofuran,
and furan.
[0027] An "antiredeposition agent" refers to a compound that helps
keep suspended in water instead of redepositing onto the object
being cleaned. Antiredeposition agents are useful in the present
invention to assist in reducing redepositing of the removed soil
onto the surface being cleaned.
[0028] As used herein, the term "cleaning" refers to a method used
to facilitate or aid in soil removal, bleaching, microbial
population reduction, and any combination thereof. As used herein,
the term "microorganism" refers to any noncellular or unicellular
(including colonial) organism. Microorganisms include all
prokaryotes. Microorganisms include bacteria (including
cyanobacteria), spores, lichens, fungi, protozoa, virinos, viroids,
viruses, phages, and some algae. As used herein, the term "microbe"
is synonymous with microorganism.
[0029] As used herein, the term "disinfectant" refers to an agent
that kills all vegetative cells including most recognized
pathogenic microorganisms, using the procedure described in
A.O.A.C. Use Dilution Methods, Official Methods of Analysis of the
Association of Official Analytical Chemists, paragraph 955.14 and
applicable sections, 15th Edition, 1990 (EPA Guideline 91-2). As
used herein, the term "high level disinfection" or "high level
disinfectant" refers to a compound or composition that kills
substantially all organisms, except high levels of bacterial
spores, and is effected with a chemical germicide cleared for
marketing as a sterilant by the Food and Drug Administration. As
used herein, the term "intermediate-level disinfection" or
"intermediate level disinfectant" refers to a compound or
composition that kills mycobacteria, most viruses, and bacteria
with a chemical germicide registered as a tuberculocide by the
Environmental Protection Agency (EPA). As used herein, the term
"low-level disinfection" or "low level disinfectant" refers to a
compound or composition that kills some viruses and bacteria with a
chemical germicide registered as a hospital disinfectant by the
EPA.
[0030] As used herein, the phrase "food processing surface" refers
to a surface of a tool, a machine, equipment, a structure, a
building, or the like that is employed as part of a food
processing, preparation, or storage activity. Examples of food
processing surfaces include surfaces of food processing or
preparation equipment (e.g., slicing, canning, or transport
equipment, including flumes), of food processing wares (e.g.,
utensils, dishware, wash ware, and bar glasses), and of floors,
walls, or fixtures of structures in which food processing occurs.
Food processing surfaces are found and employed in food
anti-spoilage air circulation systems, aseptic packaging
sanitizing, food refrigeration and cooler cleaners and sanitizers,
ware washing sanitizing, blancher cleaning and sanitizing, food
packaging materials, cutting board additives, third-sink
sanitizing, beverage chillers and warmers, meat chilling or
scalding waters, autodish sanitizers, sanitizing gels, cooling
towers, food processing antimicrobial garment sprays, and
non-to-low-aqueous food preparation lubricants, oils, and rinse
additives.
[0031] As used herein, the phrase "food product" includes any food
substance that might require treatment with an antimicrobial agent
or composition and that is edible with or without further
preparation. Food products include meat (e.g. red meat and pork),
seafood, poultry, produce (e.g., fruits and vegetables), eggs,
living eggs, egg products, ready to eat food, wheat, seeds, roots,
tubers, leafs, stems, corns, flowers, sprouts, seasonings, or a
combination thereof. The term "produce" refers to food products
such as fruits and vegetables and plants or plant-derived materials
that are typically sold uncooked and, often, unpackaged, and that
can sometimes be eaten raw.
[0032] The term "hard surface" refers to a solid, substantially
non-flexible surface such as a counter top, tile, floor, wall,
panel, window, plumbing fixture, kitchen and bathroom furniture,
appliance, engine, circuit board, and dish. Hard surfaces may
include for example, health care surfaces and food processing
surfaces.
[0033] As used herein, the phrase "health care surface" refers to a
surface of an instrument, a device, a cart, a cage, furniture, a
structure, a building, or the like that is employed as part of a
health care activity. Examples of health care surfaces include
surfaces of medical or dental instruments, of medical or dental
devices, of electronic apparatus employed for monitoring patient
health, and of floors, walls, or fixtures of structures in which
health care occurs. Health care surfaces are found in hospital,
surgical, infirmity, birthing, mortuary, and clinical diagnosis
rooms. These surfaces can be those typified as "hard surfaces"
(such as walls, floors, bed-pans, etc.,), or fabric surfaces, e.g.,
knit, woven, and non-woven surfaces (such as surgical garments,
draperies, bed linens, bandages, etc.,), or patient-care equipment
(such as respirators, diagnostic equipment, shunts, body scopes,
wheel chairs, beds, etc.,), or surgical and diagnostic equipment.
Health care surfaces include articles and surfaces employed in
animal health care.
[0034] As used herein, the term "instrument" refers to the various
medical or dental instruments or devices that can benefit from
cleaning with a composition according to the present invention.
[0035] As used herein, the phrases "medical instrument," "dental
instrument," "medical device," "dental device," "medical
equipment," or "dental equipment" refer to instruments, devices,
tools, appliances, apparatus, and equipment used in medicine or
dentistry. Such instruments, devices, and equipment can be cold
sterilized, soaked or washed and then heat sterilized, or otherwise
benefit from cleaning in a composition of the present invention.
These various instruments, devices and equipment include, but are
not limited to: diagnostic instruments, trays, pans, holders,
racks, forceps, scissors, shears, saws (e.g. bone saws and their
blades), hemostats, knives, chisels, rongeurs, files, nippers,
drills, drill bits, rasps, burrs, spreaders, breakers, elevators,
clamps, needle holders, carriers, clips, hooks, gouges, curettes,
retractors, straightener, punches, extractors, scoops, keratomes,
spatulas, expressors, trocars, dilators, cages, glassware, tubing,
catheters, cannulas, plugs, stents, scopes (e.g., endoscopes,
stethoscopes, and arthoscopes) and related equipment, and the like,
or combinations thereof.
[0036] As used herein, the phrases "objectionable odor," "offensive
odor," or "malodor," refer to a sharp, pungent, or acrid odor or
atmospheric environment from which a typical person withdraws if
they are able to. Hedonic tone provides a measure of the degree to
which an odor is pleasant or unpleasant. An "objectionable odor,"
"offensive odor," or "malodor" has an hedonic tone rating it as
unpleasant as or more unpleasant than a solution of 5 wt-% acetic
acid, propionic acid, butyric acid, or mixtures thereof.
[0037] As used herein, the term "phosphorus-free" or "substantially
phosphorus-free" refers to a composition, mixture, or ingredient
that does not contain phosphorus or a phosphorus-containing
compound or to which phosphorus or a phosphorus-containing compound
has not been added. Should phosphorus or a phosphorus-containing
compound be present through contamination of a phosphorus-free
composition, mixture, or ingredients, the amount of phosphorus
shall be less than 0.5 wt %. More preferably, the amount of
phosphorus is less than 0.1 wt-%, and most preferably the amount of
phosphorus is less than 0.01 wt % in phosphorus-free
compositions.
[0038] For the purpose of this patent application, successful
microbial reduction is achieved when the microbial populations are
reduced by at least about 50%, or by significantly more than is
achieved by a wash with water. Larger reductions in microbial
population provide greater levels of protection.
[0039] As used herein, the term "sanitizer" refers to an agent that
reduces the number of bacterial contaminants to safe levels as
judged by public health requirements. In an embodiment, sanitizers
for use in this invention will provide at least a 99.999% reduction
(5-log order reduction). These reductions can be evaluated using a
procedure set out in Germicidal and Detergent Sanitizing Action of
Disinfectants, Official Methods of Analysis of the Association of
Official Analytical Chemists, paragraph 960.09 and applicable
sections, 15th Edition, 1990 (EPA Guideline 91-2). According to
this reference a sanitizer should provide a 99.999% reduction
(5-log order reduction) within 30 seconds at room temperature,
25.+-.2.degree. C., against several test organisms. According to
other aspects of the invention, a sanitizer provides a 99.999%
reduction (5-log order reduction) at a temperature of at least
about 100.degree. F. against several test organisms, including gram
negative organisms.
[0040] As used herein, the term "soil" or "stain" refers to a
non-polar oily substance which may or may not contain particulate
matter such as mineral clays, sand, natural mineral matter, carbon
black, graphite, kaolin, environmental dust, etc.
[0041] As used in this invention, the term "sporicide" refers to a
physical or chemical agent or process having the ability to cause
greater than a 90% reduction (1-log order reduction) in the
population of spores of Bacillus cereus or Bacillus subtilis within
10 seconds at 60.degree. C. In certain embodiments, the sporicidal
compositions of the invention provide greater than a 99% reduction
(2-log order reduction), greater than a 99.99% reduction (4-log
order reduction), or greater than a 99.999% reduction (5-log order
reduction) in such population within 10 seconds at 60.degree.
C.
[0042] Differentiation of antimicrobial "-cidal" or "-static"
activity, the definitions which describe the degree of efficacy,
and the official laboratory protocols for measuring this efficacy
are considerations for understanding the relevance of antimicrobial
agents and compositions. Antimicrobial compositions can affect two
kinds of microbial cell damage. The first is a lethal, irreversible
action resulting in complete microbial cell destruction or
incapacitation. The second type of cell damage is reversible, such
that if the organism is rendered free of the agent, it can again
multiply. The former is termed microbiocidal and the later,
microbistatic. A sanitizer and a disinfectant are, by definition,
agents which provide antimicrobial or microbiocidal activity. In
contrast, a preservative is generally described as an inhibitor or
microbistatic composition
[0043] As used herein, the term "substantially free" refers to
compositions completely lacking the component or having such a
small amount of the component that the component does not affect
the performance of the composition. The component may be present as
an impurity or as a contaminant and shall be less than 0.5 wt-%. In
another embodiment, the amount of the component is less than 0.1
wt-% and in yet another embodiment, the amount of component is less
than 0.01 wt-%.
[0044] The term "substantially similar cleaning performance" refers
generally to achievement by a substitute cleaning, sanitizing
and/or rinsing product or substitute cleaning, sanitizing and/or
rinsing system of generally the same degree (or at least not a
significantly lesser degree) of cleanliness or with generally the
same expenditure (or at least not a significantly lesser
expenditure) of effort, or both.
[0045] As used herein, the term "sulfoperoxycarboxylic acid,"
"sulfonated peracid," or "sulfonated peroxycarboxylic acid" refers
to the peroxycarboxylic acid form of a sulfonated carboxylic acid.
In some embodiments, the sulfonated peracids of the present
invention are mid-chain sulfonated peracids. As used herein, the
term "mid-chain sulfonated peracid" refers to a peracid compound
that includes a sulfonate group attached to a carbon that is at
least one carbon (e.g., the three position or further) from the
carbon of the percarboxylic acid group in the carbon backbone of
the percarboxylic acid chain, wherein the at least one carbon is
not in the terminal position. As used herein, the term "terminal
position," refers to the carbon on the carbon backbone chain of a
percarboxylic acid that is furthest from the percarboxyl group.
[0046] As used herein, the term "ware" refers to items such as
eating and cooking utensils, dishes, and other hard surfaces such
as showers, sinks, toilets, bathtubs, countertops, windows,
mirrors, transportation vehicles, and floors. As used herein, the
term "warewashing" refers to washing, cleaning, or rinsing ware.
Ware also refers to items made of plastic. Types of plastics that
can be cleaned with the compositions according to the invention
include but are not limited to, those that include polycarbonate
polymers (PC), acrilonitrile-butadiene-styrene polymers (ABS), and
polysulfone polymers (PS). Another exemplary plastic that can be
cleaned using the compounds and compositions of the invention
include polyethylene terephthalate (PET).
[0047] The term "weight percent," "wt-%," "percent by weight," "%
by weight," and variations thereof, as used herein, refer to the
concentration of a substance as the weight of that substance
divided by the total weight of the composition and multiplied by
100. It is understood that, as used here, "percent," "%," and the
like are intended to be synonymous with "weight percent," "wt-%,"
etc.
[0048] The methods and compositions of the present invention may
comprise, consist essentially of, or consist of the components and
ingredients of the present invention as well as other ingredients
described herein. As used herein, "consisting essentially of" means
that the methods and compositions may include additional steps,
components or ingredients, but only if the additional steps,
components or ingredients do not materially alter the basic and
novel characteristics of the claimed methods and compositions.
[0049] It should also be noted that, as used in this specification
and the appended claims, the term "configured" describes a system,
apparatus, or other structure that is constructed or configured to
perform a particular task or adopt a particular configuration. The
term "configured" can be used interchangeably with other similar
phrases such as arranged and configured, constructed and arranged,
adapted and configured, adapted, constructed, manufactured and
arranged, and the like.
[0050] Compositions
[0051] While an understanding of the mechanism is not necessary to
practice the present invention and while the present invention is
not limited to any particular mechanism of action, it is
contemplated that, in some embodiments, equilibrium
peroxycarboxylic acid compositions are formulated with compatible
non-foaming rinse additives (i.e. surfactants) to provide
approximately neutral pH sanitizing and rinsing compositions with
suitable stability. Beneficially, the formulations according to the
present invention allow a single dual formulation of the
concentrated equilibrium peroxycarboxylic acid compositions with
the rinse aid surfactants to allow a single formulation (i.e. one
part system) instead of the separate products for cleaning,
sanitizing and/or rinsing which are customarily used in warewashing
and other cleaning and/or sanitizing applications.
[0052] It is unexpected according to the invention, that the single
formulation is able to effectively replace two or three distinct
formulations (e.g. detergent, sanitizer and rinse additive) while
providing the desired technical effect. These results were
unexpected as one skilled in the art does not expect a low-foaming
or non-foaming rinse additive or surfactant(s) to be compatible
with peroxycarboxylic acids and hydrogen peroxide. This expected
incompatibility is similar to the understanding in the art that
nonionic surfactants are also incompatible with chlorine
bleach-based sanitizing compositions. One skilled in the art
expects the bleach and/or peracid to degrade the nonionic
surfactants. Therefore, it is unexpected and highly beneficial,
according to the invention, that the particular non-foaming rinse
additives are formulated into a stable, concentrated
peroxycarboxylic acid composition.
[0053] In an embodiment, the present composition exhibits
advantageous stability of the peroxycarboxylic acid. In an aspect
of the invention, the concentrated compositions have
shelf-stability of one year at room temperature, as confirmed by
accelerated shelf-life and stability testing. In an aspect,
stability refers to the amount of peroxycarboxylic acid in the
compositions remaining at about 80% or more, about 85% or more,
about 90% or more, or about 95% or more of the initial values or
use composition levels.
[0054] It is further unexpected that the compositions provide at
least substantially similar rinsing performance to those rinse aids
or surfactants formulated into two or more part systems. According
to the invention, the one part system provides sanitizing and
sufficient rinse aid performance, including sheeting (i.e. chemical
species causes the aqueous rinse to sheet from a treated surface
such as a ware), spot-free ware and quick drying performance, in
the presence of peroxycarboxylic acid and hydrogen peroxide. As a
further unexpected benefit, the combination sanitizing and rinse
aid formulations reduce and/or do not exceed the cost to consumers
in comparison to such conventional two or three part formulations
for warewashing applications.
[0055] In an aspect, the single use, dual compositions include
concentrated equilibrium compositions comprising peroxycarboxylic
acid(s), hydrogen peroxide, corresponding carboxylic acid(s), a
solvent, e.g., water, rinse aid surfactants, and other optional
additional functional ingredients. In an aspect, the concentrated,
equilibrium liquid compositions include the exemplary ranges shown
in Table 1.
TABLE-US-00001 TABLE 1 First Second Third Exemplary Exemplary
Exemplary Range Range Range Material wt-% wt-% wt-% Solvent (e.g.
Water) 0-80 0.001-60 0.01-50 Peroxycarboxylic Acid 0.1-40 1-20 1-10
Carboxylic Acid 0.1-80 1-40 1-15 Hydrogen Peroxide 1-75 1-50 1-25
Rinse Aid Surfactants 1-50 1-25 10-25 (defoaming and wetting
surfactants) Additional Functional 0-50 1-50 10-50 Ingredients
(e.g. stabilizing agent(s), additional surfactants, coupling
agents)
[0056] Embodiments of the Concentrate Compositions
[0057] According to the invention, the concentrated, equilibrium
compositions set forth in Table 1 have acidic pHs, such as from
about 0 to about 4. However, according to aspects of the invention,
the diluted use solutions may have acidic or neutral to alkaline pH
depending upon a particular application of use thereof. In one
aspect, the pH of the use solution of the compositions is between
about 0 to about 4. In a further aspect, the pH of the use solution
of the compositions is between about 5 to about 9, preferably from
about 5.5 to about 8.5. Without limiting the scope of invention,
the numeric ranges are inclusive of the numbers defining the range
and include each integer within the defined range.
[0058] In additional aspects, the concentrated, equilibrium
compositions set forth in Table 1 are suitable for dilution and use
at temperatures up to about 100.degree. F., up to about 110.degree.
F., up to about 120.degree. F., up to about 180.degree. F., at
temperatures from about 100.degree. F. to about 140.degree. F., at
temperatures above about 140.degree. F., and at temperatures up to
or above 180.degree. F. Without limiting the scope of invention,
the numeric ranges are inclusive of the numbers defining the range
and include each integer within the defined range.
[0059] It is unexpected according to certain embodiments of the
compositions and methods of the invention that the use solutions of
neutral to alkaline pH (e.g. about 5-9) provide micro efficacy
against pathogenic organisms, including for example gram negative
organisms important for food safety sanitizing applications. This
is unexpected as a neutral pH POOA sanitizing composition was
expected to have ineffective antimicrobial efficacy against E. coli
or other gram negative organisms even at elevated temperatures
(e.g., 100.degree. F.-140.degree. F., such as those temperatures
currently required for chemical sanitization with bleach in ware
wash machines). This is evident by the use of peroxycarboxylic
acids, such as the medium length alkyl chain peracid in use
solutions having acidic pH (generally pH of less than <4.0) to
provide sufficient sanitizing efficacy against gram negative
organisms, such as E. coli.
[0060] In additional aspects, the concentrated, equilibrium
compositions set forth in Table 1 are low odor products. In
preferred aspects, the concentrated equilibrium compositions
include less than about 2 wt-% peroxyacetic acid, or preferably
exclude peroxyacetic acid. In other aspects, the concentrated,
equilibrium compositions contain short chain carboxylic acids (and
corresponding peroxycarboxylic acids) at a level insufficient to
cause odor offensive to a typical person. In certain embodiments,
the present concentrated compositions include, for example, less
than 10 wt-%, less than less than 5 wt-%, less than 2 wt-%, or less
than 1 wt-% acetic acid or other malodor-causing short chain
carboxylic acids.
[0061] The sanitizing rinse aid compositions may include
concentrate compositions or may be diluted to form use
compositions. In general, a concentrate refers to a composition
that is intended to be diluted with water to provide a use solution
that contacts an object to provide the desired cleaning, rinsing,
or the like. The sanitizing rinse aid composition that contacts the
articles to be washed can be referred to as a concentrate or a use
composition (or use solution) dependent upon the formulation
employed in methods according to the invention.
[0062] A use solution may be prepared from the concentrate by
diluting the concentrate with water at a dilution ratio that
provides a use solution having desired sanitizing and rinsing
properties. The water that is used to dilute the concentrate to
form the use composition can be referred to as water of dilution or
a diluent, and can vary from one location to another. The typical
dilution factor is between approximately 1 and approximately 10,000
but will depend on factors including water hardness, the amount of
soil to be removed from treated surfaces and the like. In an
embodiment, the concentrate is diluted at a ratio of between about
1:10 and about 1:10,000 concentrate to water. Particularly, the
concentrate is diluted at a ratio of between about 1:100 and about
1:5,000 concentrate to water. Without limiting the scope of
invention, the numeric ranges are inclusive of the numbers defining
the range and include each integer within the defined range.
[0063] The methods of making or formulating the sanitizing rinse
aid compositions according to the invention may include combining
the nonionic surfactants, carboxylic acids and hydrogen peroxide
with the other materials disclosed herein. The compositions can
also be formulated with preformed peroxycarboxylic acids. However,
preferably the compositions are made by mixing the carboxylic acid
or mixture thereof with the hydrogen peroxide to react the mixture
and adding the balance of required ingredients to form the
sanitizing rinse aid compositions. Exemplary methods are disclosed
for example in U.S. Pat. No. 7,887,641, which is herein
incorporated by reference in its entirety. Thereafter, a stable
equilibrium mixture is produced containing the carboxylic acid(s)
with hydrogen peroxide and allowing the mixture to stand for 1-7
days (or greater).
[0064] Peroxycarboxylic Acids
[0065] According to the invention, a peroxycarboxylic acid (i.e.
peracid) is included for antimicrobial efficacy in the sanitizing
and rinsing compositions disclosed herein. As used herein, the term
"peracid" may also be referred to as a "percarboxylic acid,"
"peroxycarboxylic acid" or "peroxyacid." Sulfoperoxycarboxylic
acids, sulfonated peracids and sulfonated peroxycarboxylic acids
are also included within the terms "peroxycarboxylic acid,"
"peracid" and others used herein. The terms "sulfoperoxycarboxylic
acid," "sulfonated peracid," or "sulfonated peroxycarboxylic acid"
refers to the peroxycarboxylic acid form of a sulfonated carboxylic
acid as disclosed in U.S. Pat. No. 8,344,026, and U.S. Patent
Publication Nos. 2010/0048730 and 2012/0052134, each of which are
incorporated herein by reference in their entirety. As one of skill
in the art appreciates, a peracid refers to an acid having the
hydrogen of the hydroxyl group in carboxylic acid replaced by a
hydroxy group. Oxidizing peracids may also be referred to herein as
peroxycarboxylic acids.
[0066] A peracid includes any compound of the formula
R--(COOOH).sub.n in which R can be hydrogen, alkyl, alkenyl,
alkyne, acylic, alicyclic group, aryl, heteroaryl, or heterocyclic
group, and n is 1, 2, or 3, and named by prefixing the parent acid
with peroxy. Preferably R includes hydrogen, alkyl, or alkenyl. The
terms "alkyl," "alkenyl," "alkyne," "acylic," "alicyclic group,"
"aryl," "heteroaryl," and "heterocyclic group" are as defined
herein.
[0067] As used herein, the term "alkyl" or "alkyl groups" refers to
saturated hydrocarbons having one or more carbon atoms, including
straight-chain alkyl groups (e.g., methyl, ethyl, propyl, butyl,
pentyl, hexyl, heptyl, octyl, nonyl, decyl, etc.), cyclic alkyl
groups (or "cycloalkyl" or "alicyclic" or "carbocyclic" groups)
(e.g., cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl,
cyclooctyl, etc.), branched-chain alkyl groups (e.g., isopropyl,
tert-butyl, sec-butyl, isobutyl, etc.), and alkyl-substituted alkyl
groups (e.g., alkyl-substituted cycloalkyl groups and
cycloalkyl-substituted alkyl groups). Preferably, a straight or
branched saturated aliphatic hydrocarbon chain having from 1 to 22
carbon atoms, such as, for example, methyl, ethyl, propyl,
isopropyl (1-methylethyl), butyl, tert-butyl (1,1-dimethylethyl),
and the like.
[0068] Unless otherwise specified, the term "alkyl" includes both
"unsubstituted alkyls" and "substituted alkyls." As used herein,
the term "substituted alkyls" refers to alkyl groups having
substituents replacing one or more hydrogens on one or more carbons
of the hydrocarbon backbone. Such substituents may include, for
example, alkenyl, alkynyl, halogeno, hydroxyl, alkylcarbonyloxy,
arylcarbonyloxy, alkoxycarbonyloxy, aryloxy, aryloxycarbonyloxy,
carboxylate, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl,
aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl,
alkylthiocarbonyl, alkoxyl, phosphate, phosphonato, phosphinato,
cyano, amino (including alkyl amino, dialkylamino, arylamino,
diarylamino, and alkylarylamino), acylamino (including
alkylcarbonylamino, arylcarbonylamino, carbamoyl and ureido),
imino, sulfhydryl, alkylthio, arylthio, thiocarboxylate, sulfates,
alkylsulfinyl, sulfonates, sulfamoyl, sulfonamido, nitro,
trifluoromethyl, cyano, azido, heterocyclic, alkylaryl, or aromatic
(including heteroaromatic) groups.
[0069] The term "alkenyl" includes an unsaturated aliphatic
hydrocarbon chain having from 2 to 12 carbon atoms, such as, for
example, ethenyl, 1-propenyl, 2-propenyl, 1-butenyl,
2-methyl-1-propenyl, and the like. The alkyl or alkenyl can be
terminally substituted with a heteroatom, such as, for example, a
nitrogen, sulfur, or oxygen atom, forming an aminoalkyl, oxyalkyl,
or thioalkyl, for example, aminomethyl, thioethyl, oxypropyl, and
the like. Similarly, the above alkyl or alkenyl can be interrupted
in the chain by a heteroatom forming an alkylaminoalkyl,
alkylthioalkyl, or alkoxyalkyl, for example, methylaminoethyl,
ethylthiopropyl, methoxymethyl, and the like.
[0070] Further, as used herein the term "alicyclic" includes any
cyclic hydrocarbyl containing from 3 to 8 carbon atoms. Examples of
suitable alicyclic groups include cyclopropanyl, cyclobutanyl,
cyclopentanyl, etc. In some embodiments, substituted alkyls can
include a heterocyclic group. As used herein, the term
"heterocyclic group" includes closed ring structures analogous to
carbocyclic groups in which one or more of the carbon atoms in the
ring is an element other than carbon, for example, nitrogen, sulfur
or oxygen. Heterocyclic groups may be saturated or unsaturated.
Exemplary heterocyclic groups include, but are not limited to,
aziridine, ethylene oxide (epoxides, oxiranes), thiirane
(episulfides), dioxirane, azetidine, oxetane, thietane, dioxetane,
dithietane, dithiete, azolidine, pyrrolidine, pyrroline, oxolane,
dihydrofuran, and furan. Additional examples of suitable
heterocyclic groups include groups derived from tetrahydrofurans,
furans, thiophenes, pyrrolidines, piperidines, pyridines, pyrrols,
picoline, coumaline, etc.
[0071] According to the invention, alkyl, alkenyl, alicyclic
groups, and heterocyclic groups can be unsubstituted or substituted
by, for example, aryl, heteroaryl, C.sub.1-4 alkyl, C.sub.1-4
alkenyl, C.sub.1-4 alkoxy, amino, carboxy, halo, nitro, cyano,
--SO.sub.3H, phosphono, or hydroxy. When alkyl, alkenyl, alicyclic
group, or heterocyclic group is substituted, preferably the
substitution is C.sub.1-4 alkyl, halo, nitro, amido, hydroxy,
carboxy, sulpho, or phosphono. In one embodiment, R includes alkyl
substituted with hydroxy. The term "aryl" includes aromatic
hydrocarbyl, including fused aromatic rings, such as, for example,
phenyl and naphthyl. The term "heteroaryl" includes heterocyclic
aromatic derivatives having at least one heteroatom such as, for
example, nitrogen, oxygen, phosphorus, or sulfur, and includes, for
example, furyl, pyrrolyl, thienyl, oxazolyl, pyridyl, imidazolyl,
thiazolyl, isoxazolyl, pyrazolyl, isothiazolyl, etc. The term
"heteroaryl" also includes fused rings in which at least one ring
is aromatic, such as, for example, indolyl, purinyl, benzofuryl,
etc.
[0072] According to the invention, aryl and heteroaryl groups can
be unsubstituted or substituted on the ring by, for example, aryl,
heteroaryl, alkyl, alkenyl, alkoxy, amino, carboxy, halo, nitro,
cyano, --SO.sub.3H, phosphono, or hydroxy. When aryl, aralkyl, or
heteroaryl is substituted, preferably the substitution is C.sub.1-4
alkyl, halo, nitro, amido, hydroxy, carboxy, sulpho, or phosphono.
In one embodiment, R includes aryl substituted with C.sub.1-4
alkyl.
[0073] Peracids suitable for use include any peroxycarboxylic
acids, including varying lengths of peroxycarboxylic acids (e.g.,
C1-22) that can be prepared from the acid-catalyzed equilibrium
reaction between a carboxylic acid described above and hydrogen
peroxide. A peroxycarboxylic acid can also be prepared by the
auto-oxidation of aldehydes or by the reaction of hydrogen peroxide
with an acid chloride, acid hydride, carboxylic acid anhydride,
sodium alcoholate or alkyl and aryl esters. Alternatively, peracids
can be prepared through non-equilibrium reactions, which may be
generated for use in situ, such as the methods disclosed in U.S.
Patent Publication Nos. 2012/0172440 and 2012/0172441 each titled
"In Situ Generation of Peroxycarboxylic Acids at Alkaline pH, and
Methods of Use Thereof," which are incorporated herein by reference
in their entirety. Preferably a composition of the invention
includes peroxyacetic acid, peroxyoctanoic acid, peroxypropionic
acid, peroxylactic acid, peroxyheptanoic acid, peroxyoctanoic acid
and/or peroxynonanoic acid.
[0074] In some embodiments, a peroxycarboxylic acid includes at
least one water-soluble peroxycarboxylic acid in which R includes
alkyl of 1-22 carbon atoms. For example, in one embodiment, a
peroxycarboxylic acid includes peroxyacetic acid. In another
embodiment, a peroxycarboxylic acid has R that is an alkyl of 1-22
carbon atoms substituted with a hydroxyl group or other polar
substituent such that the substituent improves the water
solubility. Methods of preparing peroxyacetic acid are known to
those of skill in the art including those disclosed in U.S. Pat.
No. 2,833,813, which is herein incorporated herein by reference in
its entirety. In other embodiments, the peroxycarboxylic may be a
combination of a short chain peroxycarboxylic acid, including for
example peroxyacetic acid and/or a medium chain peroxycarboxylic
acid, including for example those disclosed in U.S. Pat. No.
7,887,641, which is herein incorporated by reference in its
entirety.
[0075] The peroxycarboxylic acid when formed in situ generally
follows the reaction of hydrogen peroxide with the carboxylic acid
(e.g., octanoic acid or mixture of octanoic acid and acetic acid)
as shown below. This reaction is reversible and depending on the
pH, water content, and storage temperature, the reaction may take
from several hours to several days to reach equilibrium.
##STR00001## [0076] R=CH.sub.3=peroxyacetic acid (POAA) [0077]
R=C.sub.7H.sub.15=peroxyoctanoic acid (POOA)
[0078] In another embodiment, a sulfoperoxycarboxylic acid has the
following formula:
##STR00002##
wherein R.sub.1 is hydrogen, or a substituted or unsubstituted
alkyl group; R.sub.2 is a substituted or unsubstituted alkylene
group; X is hydrogen, a cationic group, or an ester forming moiety;
or salts or esters thereof. In some embodiments, R.sub.1 is a
substituted or unsubstituted C.sub.m alkyl group; X is hydrogen a
cationic group, or an ester forming moiety; R.sub.2 is a
substituted or unsubstituted C.sub.n alkyl group; m=1 to 10; n=1 to
10; and m+n is less than 18, or salts, esters or mixtures
thereof.
[0079] In some embodiments, R.sub.1 is hydrogen. In other
embodiments, R.sub.1 is a substituted or unsubstituted alkyl group.
In some embodiments, R.sub.1 is a substituted or unsubstituted
alkyl group that does not include a cyclic alkyl group. In some
embodiments, R.sub.1 is a substituted alkyl group. In some
embodiments, R.sub.1 is an unsubstituted C.sub.1-C.sub.9 alkyl
group. In some embodiments, R.sub.1 is an unsubstituted C.sub.7 or
C.sub.8 alkyl. In other embodiments, R.sub.1 is a substituted
C.sub.8-C.sub.10 alkylene group. In some embodiments, R.sub.1 is a
substituted C.sub.8-C.sub.10 alkyl group is substituted with at
least 1, or at least 2 hydroxyl groups. In still yet other
embodiments, R.sub.1 is a substituted C.sub.1-C.sub.9 alkyl group.
In some embodiments, R.sub.1 is a substituted C.sub.1-C.sub.9
substituted alkyl group is substituted with at least 1 SO.sub.3H
group. In other embodiments, R.sub.1 is a C.sub.9-C.sub.10
substituted alkyl group. In some embodiments, R.sub.1 is a
substituted C.sub.9-C.sub.10 alkyl group wherein at least two of
the carbons on the carbon backbone form a heterocyclic group. In
some embodiments, the heterocyclic group is an epoxide group.
[0080] In some embodiments, R.sub.2 is a substituted
C.sub.1-C.sub.10 alkylene group. In some embodiments, R.sub.2 is a
substituted C.sub.8-C.sub.10 alkylene. In some embodiments, R.sub.2
is an unsubstituted C.sub.6-C.sub.9 alkylene. In other embodiments,
R.sub.2 is a C.sub.8-C.sub.10 alkylene group substituted with at
least one hydroxyl group. In some embodiments, R.sub.2 is a
C.sub.10 alkylene group substituted with at least two hydroxyl
groups. In other embodiments, R.sub.2 is a C.sub.8 alkylene group
substituted with at least one SO.sub.3H group. In some embodiments,
R.sub.2 is a substituted C.sub.9 group, wherein at least two of the
carbons on the carbon backbone form a heterocyclic group. In some
embodiments, the heterocyclic group is an epoxide group. In some
embodiments, R.sub.1 is a C.sub.8-C.sub.9 substituted or
unsubstituted alkyl, and R.sub.2 is a C.sub.7-C.sub.8 substituted
or unsubstituted alkylene.
[0081] These and other suitable sulfoperoxycarboxylic acid
compounds for use in the stabilized peroxycarboxylic acid
compositions of the invention are further disclosed in U.S. Pat.
No. 8,344,026 and U.S. Patent Publication Nos. 2010/0048730 and
2012/0052134, which are incorporated herein by reference in its
entirety.
[0082] In additional embodiments a sulfoperoxycarboxylic acid is
combined with a single or mixed peroxycarboxylic acid composition,
such as a sulfoperoxycarboxylic acid with peroxyacetic acid and
peroxyoctanoic acid (PSOA/POAA/POOA). In other embodiments, a mixed
peracid is employed, such as a peroxycarboxylic acid including at
least one peroxycarboxylic acid of limited water solubility in
which R includes alkyl of 5-22 carbon atoms and at least one
water-soluble peroxycarboxylic acid in which R includes alkyl of
1-4 carbon atoms. For example, in one embodiment, a
peroxycarboxylic acid includes peroxyacetic acid and at least one
other peroxycarboxylic acid such as those named above. Preferably a
composition of the invention includes peroxyacetic acid and
peroxyoctanoic acid, such as disclosed in U.S. Pat. No. 5,314,687
which is herein incorporated by reference in its entirety. In an
aspect, the peracid mixture is a hydrophilic peracetic acid and a
hydrophobic peroctanoic acid, providing antimicrobial synergy. In
an aspect, the synergy of a mixed peracid system allows the use of
lower dosages of the peracids.
[0083] In another embodiment, a tertiary peracid mixture
composition, such as peroxysulfonated oleic acid, peracetic acid
and peroctanoic acid are employed, such as disclosed in U.S. Pat.
No. 8,344,026 which is incorporated herein by reference in its
entirety. Advantageously, a combination of peroxycarboxylic acids
provides a composition with desirable antimicrobial activity in the
presence of high organic soil loads. The mixed peroxycarboxylic
acid compositions often provide synergistic micro efficacy.
Accordingly, compositions of the invention can include a
peroxycarboxylic acid, or mixtures thereof.
[0084] Various commercial formulations of peracids are available,
including for example peracetic acid (approximately 15%) available
as EnviroSan or Victory (Ecolab, Inc., St. Paul Minn.). Most
commercial peracid solutions state a specific percarboxylic acid
concentration without reference to the other chemical components in
a use solution. In preferred embodiments, the sanitizing rinse
additive compositions exhibit low to no odor in the concentrated
formulation. In a further preferred aspect, a low odor peracid is
employed, such as peroxyoctanoic acid (POOA), to allow
significantly increased concentration of the peracid in the
sanitizing rinse aid composition without increasing the odor.
According to some preferred embodiments, the peroxycarboxylic acid
is not a peroxyacetic acid (containing the corresponding carboxylic
acid acetic acid). According to other embodiments, the
concentration of POAA in a concentrate composition is less than
about 2 wt-%, and preferably less than about 1 wt-%.
[0085] In an aspect, any suitable C.sub.1-C.sub.22 percarboxylic
acid can be used in the present compositions. In some embodiments,
the C.sub.1-C.sub.22 percarboxylic acid is a C.sub.2-C.sub.20
percarboxylic acid. In other embodiments, the C.sub.1-C.sub.22
percarboxylic is a C.sub.1, C.sub.2, C.sub.3, C.sub.4, C.sub.5,
C.sub.6, C.sub.7, C.sub.8, C.sub.9, C.sub.10, C.sub.11, C.sub.12,
C.sub.13, C.sub.14, C.sub.15, C.sub.16, C.sub.17, C.sub.18,
C.sub.19, C.sub.20, C.sub.21, or C.sub.22 carboxylic acid. In still
other embodiments, the C.sub.1-C.sub.22 percarboxylic acid
comprises peroxyacetic acid, peroxyoctanoic acid and/or
peroxysulfonated oleic acid.
[0086] In an aspect of the invention, a peracid may be selected
from a concentrated composition having a ratio of hydrogen peroxide
to peracid from about 0:10 to about 10:0, preferably from about
0.5:10 to about 10:0.5, preferably from about 1:8 to 8:1. Various
concentrated peracid compositions having the hydrogen peroxide to
peracid ratios of about 0.5:10 to about 10:0.5, preferably from
about 1:8 to 8:1, may be employed to produce a use solution for
treatment according to the methods of the invention. In a further
aspect of the invention, a peracid may have a ratio of hydrogen
peroxide to peracid as low as from about 0.01 part hydrogen
peroxide to about 1 part peracid. Without limiting the scope of
invention, the numeric ranges are inclusive of the numbers defining
the range and include each integer within the defined range.
[0087] In a preferred aspect, the C.sub.1-C.sub.22 percarboxylic
acid can be used at any suitable concentration. In some
embodiments, the C.sub.1-C.sub.22 percarboxylic acid has a
concentration from about 0.1 wt-% to about 40 wt-% in a
concentrated equilibrium composition. In other embodiments, the
C.sub.1-C.sub.22 percarboxylic acid has a concentration from about
1 wt-% to about 40 wt-%, or from about 1 wt-% to about 20 wt-%. In
still other embodiments, the C.sub.1-C.sub.22 percarboxylic acid
has a concentration at about 1 wt-%, 2 wt-%, 3 wt-%, 4 wt-%, 5
wt-%, 6 wt-%, 7 wt-%, 8 wt-%, 9 wt-%, 10 wt-%, 11 wt-%, 12 wt-%, 13
wt-%, 14 wt-%, 15 wt-%, 16 wt-%, 17 wt-%, 18 wt-%, 19 wt-%, 20
wt-%, 25 wt-%, 30 wt-%, 35 wt-%, or 40 wt-%. Without limiting the
scope of invention, the numeric ranges are inclusive of the numbers
defining the range and include each integer within the defined
range.
[0088] Carboxylic Acids
[0089] The present invention includes a carboxylic acid with the
peracid composition and hydrogen peroxide. A carboxylic acid
includes any compound of the formula R--(COOH).sub.n in which R can
be hydrogen, alkyl, alkenyl, alkyne, acylic, alicyclic group, aryl,
heteroaryl, or heterocylic group, and n is 1, 2, or 3. Preferably R
includes hydrogen, alkyl, or alkenyl. The terms "alkyl," "alkenyl,"
"alkyne," "acylic," "alicyclic group," "aryl," "heteroaryl," and
"heterocyclic group" are as defined above with respect to
peracids.
[0090] Examples of suitable carboxylic acids according to the
equilibrium systems of peracids according to the invention include
a variety monocarboxylic acids, dicarboxylic acids, and
tricarboxylic acids. Monocarboxylic acids include, for example,
formic acid, acetic acid, propanoic acid, butanoic acid, pentanoic
acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid,
decanoic acid, undecanoic acid, dodecanoic acid, glycolic acid,
lactic acid, salicylic acid, acetylsalicylic acid, mandelic acid,
etc. Dicarboxylic acids include, for example, adipic acid, fumaric
acid, glutaric acid, maleic acid, succinic acid, malic acid,
tartaric acid, etc. Tricarboxylic acids include, for example,
citric acid, trimellitic acid, isocitric acid, agaicic acid,
etc.
[0091] In an aspect of the invention, a particularly well suited
carboxylic acid is water soluble such as formic acid, acetic acid,
propionic acid, butanoic acid, lactic acid, glycolic acid, citric
acid, mandelic acid, glutaric acid, maleic acid, malic acid, adipic
acid, succinic acid, tartaric acid, etc. Preferably a composition
of the invention includes acetic acid, octanoic acid, or propionic
acid, lactic acid, heptanoic acid, octanoic acid, or nonanoic acid.
Additional examples of suitable carboxylic acids are employed in
sulfoperoxycarboxylic acid or sulfonated peracid systems, which are
disclosed in U.S. Pat. No. 8,344,026, and U.S. Patent Publication
Nos. 2010/0048730 and 2012/0052134, each of which are herein
incorporated by reference in their entirety.
[0092] Any suitable C.sub.1-C.sub.22 carboxylic acid can be used in
the present compositions. In some embodiments, the C.sub.1-C.sub.22
carboxylic acid is a C.sub.2-C.sub.20 carboxylic acid. In other
embodiments, the C.sub.1-C.sub.22 carboxylic acid is a C.sub.1,
C.sub.2, C.sub.3, C.sub.4, C.sub.5, C.sub.6, C.sub.7, C.sub.8,
C.sub.9, C.sub.10, C.sub.11, C.sub.12, C.sub.13, C.sub.14,
C.sub.15, C.sub.16, C.sub.17, C.sub.18, C.sub.19, C.sub.20,
C.sub.21, or C.sub.22 carboxylic acid. In still other embodiments,
the C.sub.1-C.sub.22 carboxylic acid comprises acetic acid,
octanoic acid and/or sulfonated oleic acid.
[0093] The C.sub.1-C.sub.22 carboxylic acid can be used at any
suitable concentration. In some embodiments, the C.sub.1-C.sub.22
carboxylic acid has a concentration in an equilibrium composition
from about 0.1 wt-% to about 80 wt-%. In other embodiments, the
C.sub.1-C.sub.22 carboxylic acid has a concentration from about 1
wt-% to about 80 wt-%. In still other embodiments, the
C.sub.1-C.sub.22 carboxylic acid has a concentration at about 1
wt-% to about 40 wt-%, or preferably from about 1 wt-% to about 15
wt-%. Without limiting the scope of invention, the numeric ranges
are inclusive of the numbers defining the range and include each
integer within the defined range.
[0094] Oxidizing Agents
[0095] The present invention includes an oxidizing agent for the
equilibrium peroxycarboxylic acid, such as hydrogen peroxide.
Hydrogen peroxide, H.sub.2O.sub.2, provides the advantages of
having a high ratio of active oxygen because of its low molecular
weight (34.014 g/mole) and being compatible with numerous
substances that can be treated by methods of the invention because
it is a weakly acidic, clear, and colorless liquid. Another
advantage of hydrogen peroxide is that it decomposes into water and
oxygen. It is advantageous to have these decomposition products
because they are generally compatible with substances being
treated. For example, the decomposition products are generally
compatible with metallic substance (e.g., substantially
noncorrosive) and are generally innocuous to incidental contact and
are environmentally friendly.
[0096] In one aspect of the invention, hydrogen peroxide is
initially in an antimicrobial peracid composition in an amount
effective for maintaining an equilibrium between a carboxylic acid,
hydrogen peroxide, and a peracid. The amount of hydrogen peroxide
should not exceed an amount that would adversely affect the
antimicrobial activity of a composition of the invention. In
further aspects of the invention, hydrogen peroxide concentration
can be significantly reduced within an antimicrobial peracid
composition. In some aspects, an advantage of minimizing the
concentration of hydrogen peroxide is that antimicrobial activity
of a composition of the invention is improved as compared to
conventional equilibrium peracid compositions.
[0097] Beneficially, in some aspects of the invention, the
sanitizing and rinsing compositions using equilibrium peracid
compositions are not reliant and/or limited according to any
particular ratio of hydrogen peroxide to peracid. In some
embodiments the inclusion of a peracid stabilizing agent (e.g. DPA)
is suitable for providing peracid stability under varying ratios of
hydrogen peroxide to peracid.
[0098] The hydrogen peroxide can be used at any suitable
concentration. In some embodiments, a concentrated equilibrium
composition has a concentration of hydrogen peroxide from about 0.5
wt-% to about 90 wt-%, or from about 1 wt-% to about 90 wt-%. In
still other embodiments, the hydrogen peroxide has a concentration
from about 1 wt-% to about 80 wt-%, from about 1 wt-% to about 50
wt-%. Without limiting the scope of invention, the numeric ranges
are inclusive of the numbers defining the range and include each
integer within the defined range.
[0099] Surfactants
[0100] According to the invention, rinse aid surfactant(s) are
included for rinsing efficacy in the sanitizing and rinsing
compositions disclosed herein. The rinse aid surfactant(s) are
required to provide rinse aid performance, including sheeting,
spot- and film-free ware and quick drying performance in the
presence of peroxycarboxylic acid and hydrogen peroxide. In further
aspects, the rinse aid surfactant(s) provide antifoaming properties
to overcome foam generated by agitation of machine sump solutions
(e.g. such as those containing proteinaceous food soils). In some
embodiments, the rinse aid surfactant(s) are stable and provide
such rinse aid performance under acidic conditions and are
accordingly referred to as acid-compatible.
[0101] In some embodiments, the compositions of the present
invention include more than one rinse aid surfactant, and
preferably include a combination of at least two rinse aid
surfactants. In some embodiments a combination of surfactants is
provided wherein one surfactant predominantly provides antifoaming
properties, and wherein the second surfactant predominantly aids in
sheeting and drying (i.e. wetting surfactant). Surfactants suitable
for use with the compositions of the present invention include
nonionic surfactants.
[0102] In some embodiments, the concentrated compositions of the
present invention include about 10 wt-% to about 50 wt-% of a
nonionic surfactant. In other embodiments the compositions of the
present invention include about 10 wt-% to about 30 wt-% of a
nonionic surfactant. In still yet other embodiments, the
compositions of the present invention include about 10 wt-% to
about 20 wt-% of a nonionic surfactant. In addition, without being
limited according to the invention, all ranges are inclusive of the
numbers defining the range and include each integer within the
defined range.
[0103] In some aspects the ratio of the defoaming to wetting
surfactants impacts the shelf-life of the sanitizing rinse aid
composition according to the invention. In a further aspect, the
ratio of the defoaming to wetting surfactants impacts the
anti-foaming capabilities of the composition. According to the
invention, in preferred aspects, the concentration of the defoaming
surfactants exceeds the concentration of the wetting surfactant. In
further aspects the ratio is from about 1:1 to about 100:1,
preferably from about 1:1 to about 50:1. In some aspects the ratio
of the defoaming surfactants to the wetting surfactants is from
about 1.5:1 to about 10:1, preferably from about 2:1 to about 5:1.
In addition, without being limited according to the invention, all
ranges for the ratios recited are inclusive of the numbers defining
the range and include each integer within the defined range of
ratios.
[0104] Nonionic Surfactants
[0105] Useful nonionic surfactants are generally characterized by
the presence of an organic hydrophobic group and an organic
hydrophilic group and are typically produced by the condensation of
an organic aliphatic, alkyl aromatic or polyoxyalkylene hydrophobic
compound with a hydrophilic alkaline oxide moiety which in common
practice is ethylene oxide or a polyhydration product thereof,
polyethylene glycol. Practically any hydrophobic compound having a
hydroxyl, carboxyl, amino, or amido group with a reactive hydrogen
atom can be condensed with ethylene oxide, or its polyhydration
adducts, or its mixtures with alkoxylenes such as propylene oxide
to form a nonionic surface-active agent. The length of the
hydrophilic polyoxyalkylene moiety which is condensed with any
particular hydrophobic compound can be readily adjusted to yield a
water dispersible or water soluble compound having the desired
degree of balance between hydrophilic and hydrophobic
properties.
[0106] In an aspect, preferred nonionic surfactants for use as the
defoaming surfactant include block polyoxypropylene-polyoxyethylene
polymeric compounds such as alcohol-EO-PO nonionic surfactants.
Exemplary alcohol-EO-PO nonionics are commercially available under
the tradename Plurafac.RTM.. Without being limited to a particular
theory of the invention, alcohol-EO-PO surfactants retain
antifoaming properties longer than polyoxypropylene-polyoxyethylene
polymeric compounds having an EOm-POn-EOm (wherein m is an integer
between 1-200, and n is an integer between 1-100) type structure
(such as those commercially-available under the tradename
Pluronic.RTM., manufactured by BASF Corp.) and compounds having an
POm-EOn-POm (wherein m is an integer between 1-100, and n is an
integer between 1-200) type structure (such as those
commercially-available under the tradename Pluronic.RTM. R, also
manufactured by BASF Corp.) due to the presence of the
peroxycarboxylic acid and hydrogen peroxide in the formulations
according to the invention.
[0107] A particularly useful group of alcohol alkoxylates are those
having the general formula R-(EO).sub.m--(PO).sub.n, wherein m is
an integer of about 1-20, preferably 1-10 and n is an integer of
about 1-20, preferably 2-20, and wherein R is any suitable radical,
including for example a straight chain alkyl group having from
about 6-20 carbon atoms.
[0108] In a further aspect, preferred nonionic surfactants include
capped or end blocked surfactants (wherein the terminal hydroxyl
group (or groups)) is capped. In an embodiment, capped aliphatic
alcohol alkoxylates include those having end caps including methyl,
ethyl, propyl, butyl, benzyl and chlorine and may have a molecular
weight of about 400 to about 10,000. Without being limited to a
particular theory of the invention, capped nonionic surfactants
provide improved stability over PO-EO-PO type or EO-PO-EO type
structure nonionics (such as those commercially-available under the
tradenames Pluronic.RTM. and Pluronic.RTM. R, manufactured by BASF
Corp). According to the invention, the capping improves the
compatibility between the nonionic surfactants and the oxidizing
hydrogen peroxide and peroxycarboxylic acids when formulated into a
single composition.
[0109] In a further aspect, preferred nonionic surfactants for use
as the wetting surfactant include alkyl ethoxylates and/or alcohol
ethoxylates. In some embodiments, the wetting agent includes one or
more alcohol ethoxylate compounds that include an alkyl group that
has 12 or fewer carbon atoms. For example, alcohol ethoxylate
compounds for use in the sanitizing rinse aids of the present
invention may each independently have structure represented by the
following formula: R--O--(CH.sub.2CH.sub.2O).sub.n--H, wherein R is
a C.sub.1-C.sub.16 alkyl group and n is an integer in the range of
1 to 100. In other embodiments, R may be a (C.sub.8-C.sub.12) alkyl
group, or may be a (C.sub.8-C.sub.10) alkyl group. Similarly, in
some embodiments, n is an integer in the range of 1-50, or in the
range of 1-30, or in the range of 1-25. In some embodiments, the
one or more alcohol ethoxylate compounds are straight chain
hydrophobes. An example of such an alcohol ethoxylate wetting
surfactant is commercially available from Sasol under the tradename
NOVEL.RTM. 1012-21 GB.
[0110] Alkyl ethoxylate surfactants terminated with methyl, benzyl,
and butyl "capping" groups are known, with the methyl and butyl
capped versions being commercially available. However, the various
alkyl ethoxylates can contain a significant amount of unprotected
(i.e., uncapped) hydroxyl groups. Therefore, there is a preference
for use of the alkyl ethoxylate surfactants to be capped to remove
the reactivity of unprotected hydroxyl groups. In a further
embodiment, the surfactant has only a single uncapped hydroxyl
group, such as the following exemplary structures:
Alkyl-(EO)m-(PO)n-POH and Alkyl-(EO)n-EOR, wherein R=alkyl
(60-80%), R=H (20-40%), and wherein m is an integer in the range
from 1 to 20 and n is an integer in the range from 1 to 20.
[0111] In some embodiments, the defoaming and wetting surfactants
used can be chosen such that they have certain characteristics, for
example, are environmentally friendly, are suitable for use in food
service industries, and/or the like. For example, the particular
alcohol ethoxylates used in the sheeting agent may meet
environmental or food service regulatory requirements, for example,
biodegradability requirements. In a preferred aspect, the nonionic
surfactants employed in the sanitizing rinse aid compositions are
approved by the U.S. EPA under CFR 180.940 for use in food contact
sanitizers. Additional nonionic surfactants include:
[0112] 1. Block polyoxypropylene-polyoxyethylene polymeric
compounds based upon propylene glycol, ethylene glycol, glycerol,
trimethylolpropane, and ethylenediamine as the initiator reactive
hydrogen compound. Examples of polymeric compounds made from a
sequential propoxylation and ethoxylation of initiator are
commercially available under the trade names Pluronic.RTM. and
Tetronic.RTM. manufactured by BASF Corp. Pluronic.RTM. compounds
are difunctional (two reactive hydrogens) compounds formed by
condensing ethylene oxide with a hydrophobic base formed by the
addition of propylene oxide to the two hydroxyl groups of propylene
glycol. This hydrophobic portion of the molecule weighs from about
1,000 to about 4,000. Ethylene oxide is then added to sandwich this
hydrophobe between hydrophilic groups, controlled by length to
constitute from about 10% by weight to about 80% by weight of the
final molecule. Tetronic.RTM. compounds are tetra-functional block
copolymers derived from the sequential addition of propylene oxide
and ethylene oxide to ethylenediamine. The molecular weight of the
propylene oxide hydrotype ranges from about 500 to about 7,000;
and, the hydrophile, ethylene oxide, is added to constitute from
about 10% by weight to about 80% by weight of the molecule.
[0113] 2. Condensation products of one mole of alkyl phenol wherein
the alkyl chain, of straight chain or branched chain configuration,
or of single or dual alkyl constituent, contains from about 8 to
about 18 carbon atoms with from about 3 to about 50 moles of
ethylene oxide. The alkyl group can, for example, be represented by
diisobutylene, di-amyl, polymerized propylene, iso-octyl, nonyl,
and di-nonyl. These surfactants can be polyethylene, polypropylene,
and polybutylene oxide condensates of alkyl phenols. Examples of
commercial compounds of this chemistry are available on the market
under the trade names Igepal.RTM. manufactured by Rhone-Poulenc and
Triton.RTM. manufactured by Union Carbide.
[0114] 3. Condensation products of one mole of a saturated or
unsaturated, straight or branched chain alcohol having from about 6
to about 24 carbon atoms with from about 3 to about 50 moles of
ethylene oxide. The alcohol moiety can consist of mixtures of
alcohols in the above delineated carbon range or it can consist of
an alcohol having a specific number of carbon atoms within this
range. Examples of like commercial surfactant are available under
the trade names Neodol.TM. manufactured by Shell Chemical Co. and
Alfonic.TM. manufactured by Vista Chemical Co.
[0115] 4. Condensation products of one mole of saturated or
unsaturated, straight or branched chain carboxylic acid having from
about 8 to about 18 carbon atoms with from about 6 to about 50
moles of ethylene oxide. The acid moiety can consist of mixtures of
acids in the above defined carbon atoms range or it can consist of
an acid having a specific number of carbon atoms within the range.
Examples of commercial compounds of this chemistry are available on
the market under the trade names Nopalcol.TM. manufactured by
Henkel Corporation and Lipopeg.TM. manufactured by Lipo Chemicals,
Inc.
[0116] In addition to ethoxylated carboxylic acids, commonly called
polyethylene glycol esters, other alkanoic acid esters formed by
reaction with glycerides, glycerin, and polyhydric (saccharide or
sorbitan/sorbitol) alcohols have application in this invention for
specialized embodiments, particularly indirect food additive
applications. All of these ester moieties have one or more reactive
hydrogen sites on their molecule which can undergo further
acylation or ethylene oxide (alkoxide) addition to control the
hydrophilicity of these substances. Care must be exercised when
adding these fatty ester or acylated carbohydrates to compositions
of the present invention containing amylase and/or lipase enzymes
because of potential incompatibility.
[0117] Examples of nonionic low foaming surfactants include:
[0118] 5. Compounds from (1) which are modified, essentially
reversed, by adding ethylene oxide to ethylene glycol to provide a
hydrophile of designated molecular weight; and, then adding
propylene oxide to obtain hydrophobic blocks on the outside (ends)
of the molecule. The hydrophobic portion of the molecule weighs
from about 1,000 to about 3,100 with the central hydrophile
including 10% by weight to about 80% by weight of the final
molecule. These reverse Pluronics.TM. are manufactured by BASF
Corporation under the trade name Pluronic.TM. R surfactants.
Likewise, the Tetronic.TM. R surfactants are produced by BASF
Corporation by the sequential addition of ethylene oxide and
propylene oxide to ethylenediamine. The hydrophobic portion of the
molecule weighs from about 2,100 to about 6,700 with the central
hydrophile including 10% by weight to 80% by weight of the final
molecule.
[0119] 6. Compounds from groups (1), (2), (3) and (4) which are
modified by "capping" or "end blocking" the terminal hydroxy group
or groups (of multi-functional moieties) to reduce foaming by
reaction with a small hydrophobic molecule such as propylene oxide,
butylene oxide, benzyl chloride; and, short chain fatty acids,
alcohols or alkyl halides containing from 1 to about 5 carbon
atoms; and mixtures thereof. Also included are reactants such as
thionyl chloride which convert terminal hydroxy groups to a
chloride group. Such modifications to the terminal hydroxy group
may lead to all-block, block-heteric, heteric-block or all-heteric
nonionics.
[0120] Additional examples of effective low foaming nonionics
include:
[0121] 7. The alkylphenoxypolyethoxyalkanols of U.S. Pat. No.
2,903,486 issued Sep. 8, 1959 to Brown et al. and represented by
the formula
##STR00003##
in which R is an alkyl group of 8 to 9 carbon atoms, A is an
alkylene chain of 3 to 4 carbon atoms, n is an integer of 7 to 16,
and m is an integer of 1 to 10.
[0122] The polyalkylene glycol condensates of U.S. Pat. No.
3,048,548 issued Aug. 7, 1962 to Martin et al. having alternating
hydrophilic oxyethylene chains and hydrophobic oxypropylene chains
where the weight of the terminal hydrophobic chains, the weight of
the middle hydrophobic unit and the weight of the linking
hydrophilic units each represent about one-third of the
condensate.
[0123] The defoaming nonionic surfactants disclosed in U.S. Pat.
No. 3,382,178 issued May 7, 1968 to Lissant et al. having the
general formula Z[(OR).sub.nOH].sub.z wherein Z is alkoxylatable
material, R is a radical derived from an alkaline oxide which can
be ethylene and propylene and n is an integer from, for example, 10
to 2,000 or more and z is an integer determined by the number of
reactive oxyalkylatable groups.
[0124] The conjugated polyoxyalkylene compounds described in U.S.
Pat. No. 2,677,700, issued May 4, 1954 to Jackson et al.
corresponding to the formula
Y(C.sub.3H.sub.6O).sub.n(C.sub.2H.sub.4O).sub.mH wherein Y is the
residue of organic compound having from about 1 to 6 carbon atoms
and one reactive hydrogen atom, n has an average value of at least
about 6.4, as determined by hydroxyl number and m has a value such
that the oxyethylene portion constitutes about 10% to about 90% by
weight of the molecule.
[0125] The conjugated polyoxyalkylene compounds described in U.S.
Pat. No. 2,674,619, issued Apr. 6, 1954 to Lundsted et al. having
the formula Y[(C.sub.3H.sub.6O.sub.n(C.sub.2H.sub.4O).sub.mH].sub.x
wherein Y is the residue of an organic compound having from about 2
to 6 carbon atoms and containing x reactive hydrogen atoms in which
x has a value of at least about 2, n has a value such that the
molecular weight of the polyoxypropylene hydrophobic base is at
least about 900 and m has value such that the oxyethylene content
of the molecule is from about 10% to about 90% by weight. Compounds
falling within the scope of the definition for Y include, for
example, propylene glycol, glycerine, pentaerythritol,
trimethylolpropane, ethylenediamine and the like. The oxypropylene
chains optionally, but advantageously, contain small amounts of
ethylene oxide and the oxyethylene chains also optionally, but
advantageously, contain small amounts of propylene oxide.
[0126] Additional conjugated polyoxyalkylene surface-active agents
which are advantageously used in the compositions of this invention
correspond to the formula:
P[(C.sub.3H.sub.6O).sub.n(C.sub.2H.sub.4O).sub.mH].sub.x wherein P
is the residue of an organic compound having from about 8 to 18
carbon atoms and containing x reactive hydrogen atoms in which x
has a value of 1 or 2, n has a value such that the molecular weight
of the polyoxyethylene portion is at least about 44 and m has a
value such that the oxypropylene content of the molecule is from
about 10% to about 90% by weight. In either case the oxypropylene
chains may contain optionally, but advantageously, small amounts of
ethylene oxide and the oxyethylene chains may contain also
optionally, but advantageously, small amounts of propylene
oxide.
[0127] 8. Polyhydroxy fatty acid amide surfactants suitable for use
in the present compositions include those having the structural
formula R.sub.2CON.sub.R1Z in which: R1 is H, C.sub.1-C.sub.4
hydrocarbyl, 2-hydroxy ethyl, 2-hydroxy propyl, ethoxy, propoxy
group, or a mixture thereof; R.sub.2 is a C.sub.5-C.sub.31
hydrocarbyl, which can be straight-chain; and Z is a
polyhydroxyhydrocarbyl having a linear hydrocarbyl chain with at
least 3 hydroxyls directly connected to the chain, or an
alkoxylated derivative (preferably ethoxylated or propoxylated)
thereof. Z can be derived from a reducing sugar in a reductive
amination reaction; such as a glycityl moiety.
[0128] 9. The alkyl ethoxylate condensation products of aliphatic
alcohols with from about 0 to about 25 moles of ethylene oxide are
suitable for use in the present compositions. The alkyl chain of
the aliphatic alcohol can either be straight or branched, primary
or secondary, and generally contains from 6 to 22 carbon atoms.
[0129] 10. The ethoxylated C.sub.6-C.sub.18 fatty alcohols and
C.sub.6-C.sub.18 mixed ethoxylated and propoxylated fatty alcohols
are suitable surfactants for use in the present compositions,
particularly those that are water soluble. Suitable ethoxylated
fatty alcohols include the C.sub.6-C.sub.18 ethoxylated fatty
alcohols with a degree of ethoxylation of from 3 to 50.
[0130] 11. Suitable nonionic alkylpolysaccharide surfactants,
particularly for use in the present compositions include those
disclosed in U.S. Pat. No. 4,565,647, Llenado, issued Jan. 21,
1986. These surfactants include a hydrophobic group containing from
about 6 to about 30 carbon atoms and a polysaccharide, e.g., a
polyglycoside, hydrophilic group containing from about 1.3 to about
10 saccharide units. Any reducing saccharide containing 5 or 6
carbon atoms can be used, e.g., glucose, galactose and galactosyl
moieties can be substituted for the glucosyl moieties. (Optionally
the hydrophobic group is attached at the 2-, 3-, 4-, etc. positions
thus giving a glucose or galactose as opposed to a glucoside or
galactoside.) The intersaccharide bonds can be, e.g., between the
one position of the additional saccharide units and the 2-, 3-, 4-,
and/or 6-positions on the preceding saccharide units.
[0131] 12. Fatty acid amide surfactants suitable for use the
present compositions include those having the formula:
R.sub.6CON(R.sub.7).sub.2 in which R.sub.6 is an alkyl group
containing from 7 to 21 carbon atoms and each R.sub.7 is
independently hydrogen, C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4
hydroxyalkyl, or --(C.sub.2H.sub.4O).sub.xH, where x is in the
range of from 1 to 3.
[0132] 13. A useful class of non-ionic surfactants include the
class defined as alkoxylated amines or, most particularly, alcohol
alkoxylated/aminated/alkoxylated surfactants. These non-ionic
surfactants may be at least in part represented by the general
formulae: R.sup.20--(PO).sub.SN-(EO).sub.tH,
R.sup.20--(PO).sub.SN-(EO).sub.tH(EO).sub.tH, and
R.sup.20--N(EO).sub.tH; in which R.sup.20 is an alkyl, alkenyl or
other aliphatic group, or an alkyl-aryl group of from 8 to 20,
preferably 12 to 14 carbon atoms, EO is oxyethylene, PO is
oxypropylene, s is 1 to 20, preferably 2-5, t is 1-10, preferably
2-5, and u is 1-10, preferably 2-5. Other variations on the scope
of these compounds may be represented by the alternative formula:
R.sup.20--(PO).sub.V--N[(EO).sub.wH][(EO).sub.zH] in which R.sup.20
is as defined above, v is 1 to 20 (e.g., 1, 2, 3, or 4 (preferably
2)), and w and z are independently 1-10, preferably 2-5. These
compounds are represented commercially by a line of products sold
by Huntsman Chemicals as nonionic surfactants. A preferred chemical
of this class includes Surfonic.TM. PEA 25 Amine Alkoxylate.
Preferred nonionic surfactants for the compositions of the
invention include alcohol alkoxylates, EO/PO block copolymers,
alkylphenol alkoxylates, and the like.
[0133] The treatise Nonionic Surfactants, edited by Schick, M. J.,
Vol. 1 of the Surfactant Science Series, Marcel Dekker, Inc., New
York, 1983 is an excellent reference on the wide variety of
nonionic compounds generally employed in the practice of the
present invention. A typical listing of nonionic classes, and
species of these surfactants, is given in U.S. Pat. No. 3,929,678
issued to Laughlin and Heuring on Dec. 30, 1975. Further examples
are given in "Surface Active Agents and detergents" (Vol. I and II
by Schwartz, Perry and Berch).
[0134] Semi-Polar Nonionic Surfactants
[0135] The semi-polar type of nonionic surface active agents are
another class of nonionic surfactant useful in compositions of the
present invention. Generally, semi-polar nonionics are high foamers
and foam stabilizers, which can limit their application in CIP
systems. However, within compositional embodiments of this
invention designed for high foam cleaning methodology, semi-polar
nonionics would have immediate utility. The semi-polar nonionic
surfactants include the amine oxides, phosphine oxides, sulfoxides
and their alkoxylated derivatives.
[0136] 14. Amine oxides are tertiary amine oxides corresponding to
the general formula:
##STR00004##
wherein the arrow is a conventional representation of a semi-polar
bond; and, R.sup.1, R.sup.2, and R.sup.3 may be aliphatic,
aromatic, heterocyclic, alicyclic, or combinations thereof.
Generally, for amine oxides of detergent interest, R.sup.1 is an
alkyl radical of from about 8 to about 24 carbon atoms; R.sup.2 and
R.sup.3 are alkyl or hydroxyalkyl of 1-3 carbon atoms or a mixture
thereof; R.sup.2 and R.sup.3 can be attached to each other, e.g.
through an oxygen or nitrogen atom, to form a ring structure;
R.sup.4 is an alkaline or a hydroxyalkylene group containing 2 to 3
carbon atoms; and n ranges from 0 to about 20.
[0137] Useful water soluble amine oxide surfactants are selected
from the coconut or tallow alkyl di-(lower alkyl) amine oxides,
specific examples of which are dodecyldimethylamine oxide,
tridecyldimethylamine oxide, etradecyldimethylamine oxide,
pentadecyldimethylamine oxide, hexadecyldimethylamine oxide,
heptadecyldimethylamine oxide, octadecyldimethylaine oxide,
dodecyldipropylamine oxide, tetradecyldipropylamine oxide,
hexadecyldipropylamine oxide, tetradecyldibutylamine oxide,
octadecyldibutylamine oxide, bis(2-hydroxyethyl)dodecylamine oxide,
bis(2-hydroxyethyl)-3-dodecoxy-1-hydroxypropylamine oxide,
dimethyl-(2-hydroxydodecyl)amine oxide,
3,6,9-trioctadecyldimethylamine oxide and
3-dodecoxy-2-hydroxypropyldi-(2-hydroxyethyl)amine oxide.
[0138] Useful semi-polar nonionic surfactants also include the
water soluble phosphine oxides having the following structure:
##STR00005##
[0139] wherein the arrow is a conventional representation of a
semi-polar bond; and, R.sup.1 is an alkyl, alkenyl or hydroxyalkyl
moiety ranging from 10 to about 24 carbon atoms in chain length;
and, R.sup.2 and R.sup.3 are each alkyl moieties separately
selected from alkyl or hydroxyalkyl groups containing 1 to 3 carbon
atoms.
[0140] Examples of useful phosphine oxides include
dimethyldecylphosphine oxide, dimethyltetradecylphosphine oxide,
methylethyltetradecylphosphone oxide, dimethylhexadecylphosphine
oxide, diethyl-2-hydroxyoctyldecylphosphine oxide,
bis(2-hydroxyethyl)dodecylphosphine oxide, and
bis(hydroxymethyl)tetradecylphosphine oxide.
[0141] Semi-polar nonionic surfactants useful herein also include
the water soluble sulfoxide compounds which have the structure:
##STR00006##
[0142] wherein the arrow is a conventional representation of a
semi-polar bond; and, R.sup.1 is an alkyl or hydroxyalkyl moiety of
about 8 to about 28 carbon atoms, from 0 to about 5 ether linkages
and from 0 to about 2 hydroxyl substituents; and R.sup.2 is an
alkyl moiety consisting of alkyl and hydroxyalkyl groups having 1
to 3 carbon atoms.
[0143] Useful examples of these sulfoxides include dodecyl methyl
sulfoxide; 3-hydroxy tridecyl methyl sulfoxide; 3-methoxy tridecyl
methyl sulfoxide; and 3-hydroxy-4-dodecoxybutyl methyl
sulfoxide.
[0144] Semi-polar nonionic surfactants for the compositions of the
invention include dimethyl amine oxides, such as lauryl dimethyl
amine oxide, myristyl dimethyl amine oxide, cetyl dimethyl amine
oxide, combinations thereof, and the like. Useful water soluble
amine oxide surfactants are selected from the octyl, decyl,
dodecyl, isododecyl, coconut, or tallow alkyl di-(lower alkyl)
amine oxides, specific examples of which are octyldimethylamine
oxide, nonyldimethylamine oxide, decyldimethylamine oxide,
undecyldimethylamine oxide, dodecyldimethylamine oxide,
iso-dodecyldimethyl amine oxide, tridecyldimethylamine oxide,
tetradecyldimethylamine oxide, pentadecyldimethylamine oxide,
hexadecyldimethylamine oxide, heptadecyldimethylamine oxide,
octadecyldimethylaine oxide, dodecyldipropylamine oxide,
tetradecyldipropylamine oxide, hexadecyldipropylamine oxide,
tetradecyldibutylamine oxide, octadecyldibutylamine oxide,
bis(2-hydroxyethyl)dodecylamine oxide,
bis(2-hydroxyethyl)-3-dodecoxy-1-hydroxypropylamine oxide,
dimethyl-(2-hydroxydodecyl)amine oxide,
3,6,9-trioctadecyldimethylamine oxide and
3-dodecoxy-2-hydroxypropyldi-(2-hydroxyethyl)amine oxide.
[0145] Suitable nonionic surfactants suitable for use with the
compositions of the present invention include alkoxylated
surfactants. Suitable alkoxylated surfactants include EO/PO
copolymers, capped EO/PO copolymers, alcohol alkoxylates, capped
alcohol alkoxylates, mixtures thereof, or the like. Suitable
alkoxylated surfactants for use as solvents include EO/PO block
copolymers, such as the Pluronic and reverse Pluronic surfactants;
alcohol alkoxylates, such as Dehypon LS-54 (R-(EO).sub.5(PO).sub.4)
and Dehypon LS-36 (R-(EO).sub.3(PO).sub.6); and capped alcohol
alkoxylates, such as Plurafac LF221 and Tegoten EC11; mixtures
thereof, or the like.
[0146] Additional Functional Ingredients
[0147] The components of the sanitizing and rinsing compositions
can further be combined with various functional components suitable
for use in ware wash and other sanitizing applications. In some
embodiments, the compositions including the peroxycarboxylic acid,
carboxylic acid, hydrogen peroxide, solvent and/or water, and/or
rinse aid surfactants make up a large amount, or even substantially
all of the total weight of the sanitizing and rinsing composition.
For example, in some embodiments few or no additional functional
ingredients are disposed therein.
[0148] In other embodiments, additional functional ingredients may
be included in the compositions. The functional ingredients provide
desired properties and functionalities to the compositions. For the
purpose of this application, the term "functional ingredient"
includes a material that when dispersed or dissolved in a use
and/or concentrate solution, such as an aqueous solution, provides
a beneficial property in a particular use. Some particular examples
of functional materials are discussed in more detail below,
although the particular materials discussed are given by way of
example only, and that a broad variety of other functional
ingredients may be used. For example, many of the functional
materials discussed below relate to materials used in cleaning,
specifically ware wash applications. However, other embodiments may
include functional ingredients for use in other applications.
[0149] In other embodiments, the compositions may include defoaming
agents, anionic surfactants, fluorescent tracers (including those
disclosed for example in U.S. patent application Ser. No.
13/785,405, which is incorporated herein by reference),
anti-redeposition agents, bleaching agents, solubility modifiers,
dispersants, additional rinse aids, antiredeposition agents, metal
protecting agents and/or etch protection convention for use in
warewashing applications, stabilizing agents, corrosion inhibitors,
additional sequestrants and/or chelating agents, humectants, pH
modifiers, fragrances and/or dyes, rheology modifiers or
thickeners, hydrotropes or couplers, buffers, solvents and the
like, such as those disclosed in U.S. Publication No. 2012/0225805,
which is herein incorporated by reference in its entirety.
[0150] Hydrotropes or Couplers
[0151] In some embodiments, the compositions of the present
invention can include a hydrotrope or coupler. These may be used to
aid in maintaining the solubility of the wetting and/or defoaming
surfactants as well as a coupling agent for the peroxycarboxylic
acid components. In some embodiments, hydrotropes are low molecular
weight n-octane sulfonate and aromatic sulfonate materials such as
alkyl benzene sulfonate, xylene sulfonates, naphthalene sulfonate,
dialkyldiphenyl oxide sulfonate materials, and cumene
sulfonates.
[0152] A hydrotrope or combination of hydrotropes can be present in
the compositions at an amount of from between about 1 wt-% to about
50 wt-%. In other embodiments, a hydrotrope or combination of
hydrotropes can be present at about 10 wt-% to about 40 wt-% of the
composition. Without limiting the scope of invention, the numeric
ranges are inclusive of the numbers defining the range and include
each integer within the defined range.
[0153] Peracid Stabilizing Agent
[0154] A peracid stabilizing agent or agents may be included in
compositions according to the invention. Beneficially, the peracid
stabilizing agent(s) prevents the decomposition of peracid in an
equilibrium peracid composition. In addition, peracid stabilizing
agent(s) may prevent an equilibrium peracid composition from
exceeding reaching their self-accelerating decomposition
temperatures (SADT).
[0155] Suitable stabilizing agents include, for example, chelating
agents or sequestrants. Suitable sequestrants include, but are not
limited to, organic chelating compounds that sequester metal ions
in solution, particularly transition metal ions. Such sequestrants
include organic amino- or hydroxy-polyphosphonic acid complexing
agents (either in acid or soluble salt forms), carboxylic acids
(e.g., polymeric polycarboxylate), hydroxycarboxylic acids,
aminocarboxylic acids, or heterocyclic carboxylic acids, e.g.,
pyridine-2,6-dicarboxylic acid (dipicolinic acid).
[0156] In some embodiments, the compositions of the present
invention include dipicolinic acid as a stabilizing agent.
Compositions including dipicolinic acid can be formulated to be
free or substantially free of phosphorous. In an aspect of the
invention, the stabilizing agent is a pyridine carboxylic acid
compound. Pyridine carboxylic acids include dipicolinic acids,
including for example, 2,6-pyridinedicarboxylic acid (DPA). In a
further aspect, the stabilizing agent is a picolinic acid, or a
salt thereof. In an aspect of the invention, the stabilizing agent
is a picolinic acid or a compound having the following Formula
(IA):
##STR00007##
wherein R.sup.1 is OH or --NR.sup.1aR.sup.1b, wherein R.sup.1a and
R.sup.1b are independently hydrogen or (C.sub.1-C.sub.6)alkyl;
R.sup.2 is OH or --NR.sup.2aR.sup.2b, wherein R.sup.2a and R.sup.2b
are independently hydrogen or (C.sub.1-C.sub.6)alkyl; each R.sup.3
is independently (C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkenyl
or (C.sub.2-C.sub.6)alkynyl; and n is a number from zero to 3; or a
salt thereof.
[0157] In a further aspect of the invention, the peracid
stabilizing agent is a compound having the following Formula
(IB):
##STR00008##
[0158] wherein R.sup.1 is OH or --NR.sup.1aR.sup.1b, wherein
R.sup.1a and R.sup.1b are independently hydrogen or
(C.sub.1-C.sub.6)alkyl; R.sup.2 is OH or --NR.sup.2aR.sup.2b,
wherein R.sup.2a and R.sup.2b are independently hydrogen or
(C.sub.1-C.sub.6)alkyl; each R.sup.3 is independently
(C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkenyl or
(C.sub.2-C.sub.6)alkynyl; and n is a number from zero to 3; or a
salt thereof. Dipicolinic acid has been used as a stabilizer for
peracid compositions, such as disclosed in WO 91/07375 and U.S.
Pat. No. 2,609,391, which are herein incorporated by reference in
their entirety.
[0159] In a further aspect, the stabilizing agent is a phosphate
stabilizer or a phosphonate based stabilizer, such as Dequest 2010.
Phosphate based stabilizers are known to act as metal chelators or
sequestrants. Conventional phosphate based stabilizing agents
include for example, 1-hydroxy ethylidene-1,1-diphosphonic acid
(CH.sub.3C(PO.sub.3H.sub.2).sub.2OH) (HEDP). In other embodiments,
the sequestrant can be or include phosphonic acid or phosphonate
salt. Suitable phosphonic acids and phosphonate salts include HEDP;
ethylenediamine tetrakis methylenephosphonic acid (EDTMP);
diethylenetriamine pentakis methylenephosphonic acid (DTPMP);
cyclohexane-1,2-tetramethylene phosphonic acid; amino[tri(methylene
phosphonic acid)]; (ethylene diamine[tetra methylene-phosphonic
acid)]; 2-phosphene butane-1,2,4-tricarboxylic acid; or salts
thereof, such as the alkali metal salts, ammonium salts, or
alkyloyl amine salts, such as mono, di, or tetra-ethanolamine
salts; picolinic, dipicolinic acid or mixtures thereof. In some
embodiments, organic phosphonates, e.g., HEDP are included in the
compositions of the present invention.
[0160] Commercially available food additive chelating agents
include phosphonates sold under the trade name DEQUEST.RTM.
including, for example, 1-hydroxyethylidene-1,1-diphosphonic acid,
available from Monsanto Industrial Chemicals Co., St. Louis, Mo.,
as DEQUEST.RTM. 2010; amino(tri(methylenephosphonic acid)),
(N[CH.sub.2PO.sub.3H.sub.2].sub.3), available from Monsanto as
DEQUEST.RTM. 2000; ethylenediamine[tetra(methylenephosphonic acid)]
available from Monsanto as DEQUEST.RTM. 2041; and
2-phosphonobutane-1,2,4-tricarboxylic acid available from Mobay
Chemical Corporation, Inorganic Chemicals Division, Pittsburgh,
Pa., as Bayhibit.RTM. AM.
[0161] According to various embodiments of the invention, the
stabilizing agent can be or include aminocarboxylic acid type
sequestrants. Suitable aminocarboxylic acid type sequestrants
include the acids or alkali metal salts thereof, e.g., amino
acetates and salts thereof. Suitable aminocarboxylates include
N-hydroxyethylaminodiacetic acid; hydroxyethylenediaminetetraacetic
acid, nitrilotriacetic acid (NTA); ethylenediaminetetraacetic acid
(EDTA); N-hydroxyethyl-ethylenediaminetriacetic acid (HEDTA);
diethylenetriaminepentaacetic acid (DTPA); and alanine-N,N-diacetic
acid; and the like; and mixtures thereof.
[0162] According to still further embodiments of the invention, the
stabilizing agent can be or include The sequestrant can be or
include a polycarboxylate. Suitable polycarboxylates include, for
example, polyacrylic acid, maleic/olefin copolymer, acrylic/maleic
copolymer, polymethacrylic acid, acrylic acid-methacrylic acid
copolymers, hydrolyzed polyacrylamide, hydrolyzed
polymethacrylamide, hydrolyzed polyamide-methacrylamide copolymers,
hydrolyzed polyacrylonitrile, hydrolyzed polymethacrylonitrile,
hydrolyzed acrylonitrile-methacrylonitrile copolymers, polymaleic
acid, polyfumaric acid, copolymers of acrylic and itaconic acid,
phosphino polycarboxylate, acid or salt forms thereof, mixtures
thereof, and the like.
[0163] In other embodiments the stabilizing agent may be a
low-phosphate or a phosphate-free stabilizer to provide either
low-phosphate or phosphate-free sanitizing and rinsing
compositions.
[0164] In a still further aspect, a combination of more than one
stabilizing agent may be employed. Stabilizing agent(s) may be
present in amounts sufficient to provide the intended stabilizing
benefits, namely achieving the desired shelf life and/or elevating
the SADT of a concentrated peroxycarboxylic acid composition.
Peracid stabilizing agents may be present in a concentrated
equilibrium peracid composition in amounts from about 0.001 wt-% to
about 25 wt-%, 0.01 wt-% to about 10 wt-%, and more preferably from
about 0.1 wt-% to about 10 wt-%. Without limiting the scope of
invention, the numeric ranges are inclusive of the numbers defining
the range and include each integer within the defined range.
[0165] Defoaming Agent
[0166] The present invention may include a defoaming agent.
Defoaming agents suitable for use in the peroxycarboxylic acid
compositions according to the invention are compatible with peracid
compositions and the nonionic surfactants in the single, dual
functioning sanitizing and rinsing formulations. The defoaming
agents suitable for use in the peroxycarboxylic acid compositions
according to the invention, maintain a low foam profile under
various water conditions, preferably under deionized or soft water
conditions, and/or under mechanical action. In a still further
aspect, the defoaming agents are compatible with surfactants,
preferably anionic surfactants, to achieve critical performance
such as coupling/wetting, improved material compatibility and
enhanced biocidal efficacy. In preferred aspects, the defoaming
agent provides a synergistic biocidal efficacy.
[0167] In an aspect of the invention, the defoaming agent is a
metal salt, including for example, aluminum, magnesium, calcium,
zinc and/or other rare earth metal salts. In a preferred aspect,
the defoaming agent is a cation with high charge density, such as
Fe.sup.3+, Al.sup.3+ and La.sup.3+. In a preferred aspect, the
defoaming agent is aluminum sulfate. In other aspects, the
defoaming agent is not a transition metal compound. In some
embodiments, the compositions of the present invention can include
antifoaming agents or defoamers which are of food grade quality,
including for example silicone-based products, given the
application of the method of the invention.
[0168] In an aspect of the invention, the defoaming agent can be
used at any suitable concentration to provide defoaming with the
surfactants according to the invention. In some embodiments, a
concentrated equilibrium composition has a concentration of the a
defoaming agent from about 0.001 wt-% to about 10 wt-%, or from
about 0.1 wt-% to about 5 wt-%. In still other embodiments, the
defoaming agent has a concentration from about 0.1 wt-% to about 1
wt-%. Without limiting the scope of invention, the numeric ranges
are inclusive of the numbers defining the range and include each
integer within the defined range.
[0169] Anti-Redeposition Agents
[0170] The sanitizing rinse aid compositions can optionally include
an anti-redeposition agent capable of facilitating sustained
suspension of soils in a rinse solution and preventing removed
soils from being redeposited onto the substrate being rinsed. Some
examples of suitable anti-redeposition agents can include fatty
acid amides, fluorocarbon surfactants, complex phosphate esters,
styrene maleic anhydride copolymers, and cellulosic derivatives
such as hydroxyethyl cellulose, hydroxypropyl cellulose, and the
like. A rinse aid composition may include up to about 10 wt-% of an
anti-redeposition agent.
[0171] Methods of Use
[0172] In an aspect, the present invention includes use of the
compositions for sanitizing and rinsing surfaces and/or products.
In another aspect, the compositions of the invention are
particularly suitable for use as a hard surface cleaner and/or
sanitizer, food contact sanitizer (including direct or indirect
contact sanitizer), tissue contact sanitizer (including for example
fruits and vegetables), fast drying sanitizer for various hard
surfaces (including for example healthcare surfaces, instruments,
food and/or beverage surfaces, processing surfaces, and the like),
any-streaking or smearing hard surface sanitizer, and the like. The
present methods can be used in the methods, processes or procedures
described and/or claimed in U.S. Pat. Nos. 5,200,189, 5,314,687,
5,718,910, 6,165,483, 6,238,685B1, 8,017,409 and 8,236,573, each of
which are herein incorporated by reference in their entirety.
[0173] The methods of use are particularly suitable for
warewashing. Suitable methods for using the sanitizing rinse aid
compositions for warewashing are set forth in U.S. Pat. No.
5,578,134, which is herein incorporated by reference in its
entirety. Beneficially, according to various embodiments of the
invention, the methods provide the following unexpected benefits:
decrease in utilities for a warewashing machine to the those
expected of commercially-available low temperature ware wash
machines, including door machines; utility consumption equivalent
to dish machines employed for chlorine-based sanitizing, including
for example commercially-available 120 Volt, 30 Amp dishwash
machines; and suitable for use with a single, dual-functioning
composition containing a detergent(s), rinse additive(s) and an
optional additional functional component for sanitizing and/or
rinsing. In still further embodiments of the invention, the methods
for warewashing may additionally provide any one or more of the
following unexpected benefits for warewashing applications:
improved ware washing results (including sanitizing efficacy and/or
rinsing); decreased total utility costs for door dishmachines;
elimination of any need for rewashing of wares; chlorine-free
formulations; and/or low phosphorous formulations or substantially
phosphorous-free formulations.
[0174] Exemplary articles in the warewashing industry that can be
treated with a sanitizing rinse aid composition according to the
invention include plastics, dishware, cups, glasses, flatware, and
cookware. For the purposes of this invention, the terms "dish" and
"ware" are used in the broadest sense to refer to various types of
articles used in the preparation, serving, consumption, and
disposal of food stuffs including pots, pans, trays, pitchers,
bowls, plates, saucers, cups, glasses, forks, knives, spoons,
spatulas, and other glass, metal, ceramic, plastic composite
articles commonly available in the institutional or household
kitchen or dining room. In general, these types of articles can be
referred to as food or beverage contacting articles because they
have surfaces which are provided for contacting food and/or
beverage. When used in these warewashing applications, the rinse
aid should provide effective sheeting action and low foaming
properties. In addition to having the desirable properties
described above, it may also be useful for the sanitizing rinse aid
composition to be biodegradable, environmentally friendly, and
generally nontoxic. A rinse aid of this type may be described as
being "food grade".
[0175] The methods of use are suitable for treating a variety of
surfaces, products and/or target in addition to ware. For example,
these may include a food item or a plant item and/or at least a
portion of a medium, a container, an equipment, a system or a
facility for growing, holding, processing, packaging, storing,
transporting, preparing, cooking or serving the food item or the
plant item. The present methods can be used for treating any
suitable plant item. In some embodiments, the plant item is a
grain, fruit, vegetable or flower plant item, a living plant item
or a harvested plant item. In addition, the present methods can be
used for treating any suitable food item, e.g., an animal product,
an animal carcass or an egg, a fruit item, a vegetable item, or a
grain item. In still other embodiments, the food item may include a
fruit, grain and/or vegetable item.
[0176] In a still further embodiment, the methods of the invention
are suitable for meeting various regulatory standards, including
for example EPA food contact sanitizers requiring at least a 5 log
reduction in pathogenic microorganisms in 30 seconds and/or NSF
standards similarly requiring at least a 5 log reduction in treated
pathogenic microorganisms. In still further aspects, without
limiting the scope of the invention, the methods of the invention
may provide sufficient sanitizing efficacy at conditions more or
less strenuous than such regulatory standards.
[0177] The present methods can be used for treating a target that
is at least a portion of a container, an equipment, a system or a
facility for holding, processing, packaging, storing, transporting,
preparing, cooking or serving the food item or the plant item. In
some embodiments, the target is at least a portion of a container,
an equipment, a system or a facility for holding, processing,
packaging, storing, transporting, preparing, cooking or serving a
meat item, a fruit item, a vegetable item, or a grain item. In
other embodiments, the target is at least a portion of a container,
an equipment, a system or a facility for holding, processing,
packaging, storing, or transporting an animal carcass. In still
other embodiments, the target is at least a portion of a container,
an equipment, a system or a facility used in food processing, food
service or health care industry. In yet other embodiments, the
target is at least a portion of a fixed in-place process facility.
An exemplary fixed in-place process facility can comprise a milk
line dairy, a continuous brewing system, a pumpable food system or
a beverage processing line.
[0178] The present methods can be used for treating a target that
is at least a portion of a solid surface. In some embodiments, the
solid surface is an inanimate solid surface. The inanimate solid
surface can be contaminated by a biological fluid, e.g., a
biological fluid comprising blood, other hazardous body fluid, or a
mixture thereof. In other embodiments, the solid surface can be a
contaminated surface. An exemplary contaminated surface can
comprise the surface of food service wares or equipment.
[0179] The various methods of treatment can include the use of any
suitable level of the peroxycarboxylic acid. In some embodiments,
the treated target composition comprises from about 1 ppm to about
1000 ppm of the peroxycarboxylic acid when diluted for use,
including any of the peroxycarboxylic acid compositions according
to the invention. The various applications of use described herein
provide the peroxycarboxylic acid compositions to a surface and/or
product in need of sanitizing and rinsing. Beneficially, the
compositions of the invention are fast-acting. However, the present
methods require a certain minimal contact time of the compositions
with the surface, liquid and/or product in need of treatment for
occurrence of sufficient antimicrobial effect. The contact time can
vary with concentration of the use compositions, method of applying
the use compositions, temperature of the use compositions, pH of
the use compositions, amount of the surface, liquid and/or product
to be treated, amount of soil or substrates on/in the surface,
liquid and/or product to be treated, or the like. The contact or
exposure time can be about 15 seconds, at least about 15 seconds,
about 30 seconds or greater than 30 seconds. In some embodiments,
the exposure time is about 1 to 5 minutes. In other embodiments,
the exposure time is at least about 10 minutes, 30 minutes, or 60
minutes. In other embodiments, the exposure time is a few minutes
to hours. In other embodiments, the exposure time is a few hours to
days. The contact time will further vary based upon the
concentration of peracid in a use solution.
[0180] The present methods can be conducted at any suitable
temperature. In some embodiments, the present methods are conducted
at a temperature ranging from about 0.degree. C. to about
70.degree. C., e.g., from about 0.degree. C. to about 4.degree. C.
or 5.degree. C., from about 5.degree. C. to about 10.degree. C.,
from about 11.degree. C. to about 20.degree. C., from about
21.degree. C. to about 30.degree. C., from about 31.degree. C. to
about 40.degree. C., including at about 37.degree. C., from about
41.degree. C. to about 50.degree. C., from about 51.degree. C. to
about 60.degree. C., or from about 61.degree. C. to about
82.degree. C., or at increased temperatures there above suitable
for a particular application of use.
[0181] The compositions are suitable for antimicrobial efficacy
against a broad spectrum of microorganisms, providing broad
spectrum bactericidal and fungistatic activity. For example, the
peracid biocides of this invention provide broad spectrum activity
against wide range of different types of microorganisms (including
both aerobic and anaerobic microorganisms, gram positive and gram
negative microorganisms), including bacteria, yeasts, molds, fungi,
algae, and other problematic microorganisms.
[0182] The present methods can be used to achieve any suitable
reduction of the microbial population in and/or on the target or
the treated target composition. In some embodiments, the present
methods can be used to reduce the microbial population in and/or on
the target or the treated target composition by at least one
log.sub.10. In other embodiments, the present methods can be used
to reduce the microbial population in and/or on the target or the
treated target composition by at least two log.sub.10. In still
other embodiments, the present methods can be used to reduce the
microbial population in and/or on the target or the treated target
composition by at least three log.sub.10. In still other
embodiments, the present methods can be used to reduce the
microbial population in and/or on the target or the treated target
composition by at least five log.sub.10. Without limiting the scope
of invention, the numeric ranges are inclusive of the numbers
defining the range and include each integer within the defined
range.
[0183] The peroxycarboxylic acid compositions may include
concentrate compositions or may be diluted to form use
compositions. In general, a concentrate refers to a composition
that is intended to be diluted with water to provide a use solution
that contacts a surface and/or product in need of treatment to
provide the desired cleaning, sanitizing or the like. The
peroxycarboxylic acid composition that contacts the surface and/or
product in need of treatment can be referred to as a concentrate or
a use composition (or use solution) dependent upon the formulation
employed in methods according to the invention. It should be
understood that the concentration of the peroxycarboxylic acid in
the composition will vary depending on whether the composition is
provided as a concentrate or as a use solution.
[0184] A use solution may be prepared from the concentrate by
diluting the concentrate with water at a dilution ratio that
provides a use solution having desired sanitizing and/or other
antimicrobial properties. The water that is used to dilute the
concentrate to form the use composition can be referred to as water
of dilution or a diluent, and can vary from one location to
another. The typical dilution factor is between approximately 1 and
approximately 10,000 but will depend on factors including water
hardness, the amount of soil to be removed and the like. In an
embodiment, the concentrate is diluted at a ratio of between about
1:10 and about 1:10,000 concentrate to water. Particularly, the
concentrate is diluted at a ratio of between about 1:100 and about
1:5,000 concentrate to water. More particularly, the concentrate is
diluted at a ratio of between about 1:250 and about 1:2,000
concentrate to water.
[0185] In a preferred aspect, the highly concentrated
peroxycarboxylic acid of the sanitizing rinse additive composition
is diluted from about 0.001% (wt/vol.) to about 2% (wt/vol.), or
from about 0.001% (wt/vol.) to about 1% (wt/vol.), or from about
0.01% (wt/vol.) to about 0.05% (wt/vol.), and preferably to
approximately 0.025% (wt/vol.). Without being limited to a
particular dilution of the concentrated sanitizing rinse additive
composition, in some aspects this dilution corresponds to
approximately 0.5 mL to about 3 mL of the liquid concentrate per
dish machine cycle (as one skilled in the art understands to
further dependent on the rinse water volume of the dish machine).
Without limiting the scope of invention, the numeric ranges are
inclusive of the numbers defining the range and include each
integer within the defined range.
[0186] All publications and patent applications in this
specification are indicative of the level of ordinary skill in the
art to which this invention pertains. All publications and patent
applications are herein incorporated by reference to the same
extent as if each individual publication or patent application was
specifically and individually indicated as incorporated by
reference.
EXAMPLES
[0187] Embodiments of the present invention are further defined in
the following non-limiting Examples. It should be understood that
these Examples, while indicating certain embodiments of the
invention, are given by way of illustration only. From the above
discussion and these Examples, one skilled in the art can ascertain
the essential characteristics of this invention, and without
departing from the spirit and scope thereof, can make various
changes and modifications of the embodiments of the invention to
adapt it to various usages and conditions. Thus, various
modifications of the embodiments of the invention, in addition to
those shown and described herein, will be apparent to those skilled
in the art from the foregoing description. Such modifications are
also intended to fall within the scope of the appended claims.
Example 1
[0188] The biocidal efficacy of various equilibrium
peroxycarboxylic acid compositions shown in Table 2 according to
the invention were evaluated to demonstrate the effect of
temperature on the peroxycarboxylic acid efficacy. AOAC Official
Method 960.09 (Germicidal and Detergent Sanitizing Action of
Disinfectants) was employed to test the compositions. The testing
was conducted on a POOA based sanitizer (commercially-available
under the tradename Octave.TM., Ecolab Inc.) having approximately 1
wt-% POOA and 7.5 wt-% hydrogen peroxide. The POOA sanitizer was
tested at different concentrations (5, 8, and 12 ppm active POOA),
different pH levels (3.5 and 5.5) and different temperatures
relevant applicable to commercial ware washing (120.degree. F. and
140.degree. F.). The results are set forth in Table 2.
TABLE-US-00002 TABLE 2 Use- Avg. Log.sub.10 Reduction Concentration
solution Use-solution in 30 sec (ppm POOA) pH Temperature S. aureus
E. coli 5 ppm pH 3.50 120.degree. F. 7.10 >7.01 pH 5.50 5.84
1.67 8 ppm pH 3.50 6.40 >7.01 pH 5.50 >7.10 1.99 12 ppm pH
3.50 >7.10 >7.01 pH 5.50 6.68 >7.01 5 ppm pH 3.50
140.degree. F. >7.12 >6.97 pH 5.50 >7.12 4.58 8 ppm pH
3.50 >7.12 >6.97 pH 5.50 >7.12 >6.97 12 ppm pH 3.50
>7.12 >6.97 pH 5.50 >7.12 >6.97
[0189] As shown in Table 2, at pH 3.5, complete E. coli kill was
achieved regardless of POOA concentration or temperature. However
at pH 5.5, only the highest concentration of POOA (12 ppm) was able
to achieve complete kill 120.degree. F. Repeating the experiment at
140.degree. F. resulted in complete kill at 8 ppm POOA and an
improvement of approximately 3 log for the 5 ppm POOA dilution.
Example 2
[0190] Various sanitizing rinse aid formulations were prepared by
mixing the components described in Table 3.
TABLE-US-00003 TABLE 3 Formulation ID 13505-29-01 Component Wt-%
H.sub.2O.sub.2 (50%) 1-80 Octanoic acid 1-10 Acetic acid 1-10
Dequest 2010 1-10 SXS (40%) 10-25 Pluronic 25R2 1-25 Novel 1021 GB
1-20 Total 100.00
[0191] The rinse aid surfactants Pluronic 25R2 and Novel 1021 GB
were used as the antifoaming and rinse aid imparting surfactants in
initial formulations of the concentrated compositions. The
composition set forth in Table 3 exhibited sufficient initial
stability and antifoaming properties. However, the surfactants
demonstrated reaction with the generated peracid and/or hydrogen
peroxide of the formulations.
[0192] This reaction was accelerated at elevated temperatures,
e.g., 40.degree. C., and ultimately resulted in phase separation of
the concentrates and/or degradation of the antifoaming properties
imparted by antifoaming surfactant Pluronic 25R2 in comparison to
the initial concentrated composition. Without being limited to a
particular theory of the invention, a potential mechanism of action
of such reaction with the peracid and/or hydrogen peroxide is the
terminal alcohol functional groups of the surfactants acting as
reaction points (e.g., alcohols demonstrated limited stability in
the presence of hydrogen peroxide and peroxycarboxylic acids).
[0193] Due to the reaction of the surfactants with the peracid
and/or hydrogen peroxide, the Pluronic type surfactant having two
terminal hydroxyl functional groups per molecule was replaced with
a surfactant having only one terminal hydroxyl group to determine
whether improved stability resulted.
[0194] The Glewwe foam test method was used to identify other
surfactants with similar antifoaming properties to Pluronic 25R2
that could be screened for potentially improved stability to
peracid chemistries in the sanitizing rinse aid compositions
according to the invention.
[0195] A Glewwe Foam meter provides a dynamic foam test rather than
a static test (as in the case of the Ross-Miles foam test). A
dynamic foam meter is considered more appropriate for simulation of
industrial conditions, e.g., the conditions in a dish machine. The
equipment and general procedure for the Glewwe form test is
described in U.S. Pat. No. 3,899,387, column 12, line 45 et seq,
which is herein incorporated by reference in its entirety. The foam
meter itself consists of a thermostated reservoir and a pump to
recirculate the aqueous medium with foaming tendencies. The foam
developed by the action of the aqueous stream impinging on the
surface in the reservoir causes foam formation.
[0196] The foam heights of the tested compositions were determined
using the following method. First 3000 mL of each formula was
prepared and gently poured into Glewwe cylinder. The foam height is
measured after various time intervals and provides a relative
measure of the effectiveness of the defoamer. The reservoir of this
foam meter consists of a stainless steel laboratory beaker of 3,000
mL capacity. Sealed to this beaker by means of a silicone sealant
is a clear Plexiglass tubing which snugly fits into the inner walls
of the beaker. This enables the operator to measure the foam height
above the liquor level. The beaker measures about 19 cm high by
about 17 to 18 cm in diameter and the Plexiglass tube extends about
30 to 35 cm above the lip of this beaker. Further detail regarding
the Glewwe foam test is shown in, U.S. Pat. No. 5,447,648, which is
expressly incorporated by reference herein.
[0197] A ruler was attached to the side of the cylinder, and the
solution was level with the bottom of the ruler. The pump was
turned on. Foam height was estimated by reading the average level
of foaming according to the ruler. Foam height readings were taken
versus time with a stopwatch or timer. The pump was turned off and
height of the foam was recorded at various times.
[0198] The results are shown in Table 4. All surfactants were
tested at 50 ppm and the temperature was 120.degree. F. Surfactants
highlighted in "gray" in Table 4 exhibited substantially similar
antifoaming properties as Pluronic 25R2. Formulations were prepared
using these lead candidates and monitored for phase stability
properties over time while stored at elevated temperature (either
40.degree. C. or 50.degree. C.).
TABLE-US-00004 TABLE 4 ##STR00009##
[0199] Exemplary tested formulations employing commercially
available nonionic surfactants are shown in Table 5.
TABLE-US-00005 TABLE 5 Formula ID 13505-29-01 13505-77-04
13505-77-05 13505-77-06 13505-77-07 13505-77-08 13505-77-09
13505-77-10 13505-77-11 H2O2 (50%) 40-60 30-50 30-50 30-50 30-50
30-50 30-50 30-50 30-50 Octanoic acid 1-10 1-10 1-10 1-10 1-10 1-10
1-10 1-10 1-10 Acetic acid 1-5 1-5 1-5 1-5 1-5 1-5 1-5 1-5 1-5 DPA
0.00 0.01-0.2 0.01-0.2 0.01-0.2 0.01-0.2 0.01-0.2 0.01-0.2 0.01-0.2
0.01-0.2 Dequest 2010 2-5 1-5 1-5 1-5 1-5 1-5 2-5 2-5 2-5 SXS (40%)
20-30 35-45 30-40 35-45 30-40 30-40 30-40 30-40 30-40 Water 0.00
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Plurafac SLF- 0.00 5-10
10-20 0.00 0.00 0.00 0.00 0.00 0.00 18 Plurafac S305 0.00 0.00 0.00
5-10 10-20 0.00 0.00 0.00 0.00 LF Plurafac SLF- 0.00 0.00 0.00 0.00
0.00 5-10 10-20 0.00 0.00 180 Pluronic 25R2 5-15 0.00 0.00 0.00
0.00 0.00 0.00 5-10 10-20 D-500 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 Novel 1021 1-10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
GB Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
100.00 Phase Stable N Y Y Y Y Y Y N N 4 wks @ 40.degree. C. Formula
ID 13505-78-02 13505-78-04 13505-78-06 13505-80-02 13505-82-12
13505-84-05 13642-08-01 H2O2 (50%) 30-50 30-50 30-50 30-50 30-50
30-50 30-50 Octanoic acid 1-10 1-10 1-10 1-10 1-10 1-10 1-10 Acetic
acid 2-6 2-6 2.25 0.00 1-5 1-5 0.00 DPA 0.01-0.2 0.01-0.2 0.01-0.2
0.01-0.2 0.01-0.2 0.01-0.2 0.01-0.2 Dequest 2010 2-5 2-5 2-5 2-5
2-5 2-5 2-5 SXS (40%) 30-40 30-40 30-40 30-40 30-40 30-40 30-40
Water 0.00 0.00 0.00 1-5 0.00 0.00 0.00 Plurafac SLF- 5-15 0.00
0.00 5-15 0.00 0.00 0.00 18 Plurafac S305 0.00 5-15 0.00 0.00 0.00
0.00 0.00 LF Plurafac SLF- 0.00 0.00 5-15 0.00 0.00 5-15 5-15 180
Pluronic 25R2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 D-500 0.00 0.00
0.00 0.00 5-15 0.00 0.00 Novel 1021 GB 1-10 1-10 1-10 0.00 1-10
1-10 1-10 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00
Phase Stable 4 Y Y Y Y Y Y Y wks @ 40.degree. C.
[0200] The results shown in Table 5 demonstrate that the
"antifoaming" surfactants evaluated, showed improved results when
employing a nonionic surfactant with an alkyl -EO--PO type
structure having a single hydroxyl functional group per molecule
(such as those commercially-available as the Plurafac.RTM.-types of
surfactants), which demonstrated increased phase stability over the
non-alkyl -EO-PO type structures or reverse Pluronic surfactants
tested.
[0201] The improved stability of the alkyl-EO-PO surfactants
supports the proposed, non-limiting, mechanism of action of the
hydroxyl groups on the surfactants being the reactive sites leading
to instability with the peroxycarboxylic acids and/or hydrogen
peroxide of the sanitizing rinse aid formulations. Accordingly, the
protection of the hydroxyl end group(s) by capping with an alkyl
group leads to unexpected improvements in stabilizing the nonionic
surfactants of the peroxycarboxylic acid sanitizing rinse aid
compositions. This increase in stability by protecting the hydroxyl
end group(s) by capping with an alkyl group was further analyzed
using the following structures to determine impact on phase
stability as shown in Table 6.
TABLE-US-00006 TABLE 6 Days phase Example Surfactant stable Formula
ID (15% in formula) Surfactant structure @50.degree. C. 13505-29-01
Pluronic 25R2 HOP-(PO)n-(EO)m- 5-7 (PO)n-POH 13642-16-01 Plurafac
SLF-180 Alkyl-(EO)n-(PO)n-POH 9-12 13642-16-05 Plurafac LF 131
Alkyl-(EO)n-EOR* 16-18 *R = alkyl (60-80%), R = H (20-40%)
Example 3
[0202] Based on the stability data obtained from Example 2 largely
dependent on the formulation of the defoaming nonionic surfactant
of the sanitizing rinse aid composition, additional testing on the
formulation of the wetting surfactant was completed. The wetting
surfactant is further needed as a coupling agent for the
peroxycarboxylic acid component of the sanitizing rinse aid
composition.
[0203] The ability of various wetting nonionic surfactants was
analyzed to confirm ability to retain coupling power when
formulated into the one part sanitizing rinse aid formulations
according to the invention. As shown in Table 7, the phase
stability and antifoam property results for formulations utilizing
various nonionic surfactants were evaluated. NAS-FAL refers to
sodium octanesulfonate (NAS-FAL) and Novel 1021 refers to a
commercially-available alcohol ethoxylate (Sasol), which were
combined as coupling agents with both capped (e.g., Plurafac LF
131) and non-capped (e.g., Plurafac SLF-180) antifoaming
surfactants.
TABLE-US-00007 TABLE 7 Anti- Anti- Foam Foam Stability Stability (7
d @ (30 d @ Surfactant composition Days phase stable 50 C.) 40 C.)
ID in Formula 122 F. 100 F. Pass/Fail Pass/Fail 13642- 15% SLF-180
9-11 36-39 Pass * 16-01 13642- 12% SLF-180 + 3% Novel1012 9-11 46
Pass * 16-02 13642- 12% SLF-180 + 3% Novel810 9-11 46 Pass * 16-03
13642- 12% SLF-180 + 3% Novel TDA 9-11 46 Fail * 16-04 13642- 14%
SLF-180 + 1% NAS-FAL 12 107+ Pass Pass 16-09 13642- 13% SLF-180 +
2% NAS-FAL 15 197 (ongoing) Pass Pass 16-10 13642- 12% SLF-180 + 3%
NAS-FAL 18-20 216 (ongoing) Fail * 06-09 13642- 15% LF 131 16-18
107-109 Pass * 16-05 13642- 12% LF 131 + 3% Novel1012 19 104 Fail *
16-06 13642- 12% LF 131 + 3% Novel810 19 107+ Fail Fail 16-07
13642- 12% LF 131 + 3% Novel TDA 19 68 Fail Fail 16-08 13642- 14%
LF 131 + 1% NAS-FAL 23-25 197 (ongoing) Fail Fail 16-11 13642- 13%
LF 131 + 2% NAS-FAL 30-32 197 (ongoing) Fail Fail 16-12 * not
tested; Note: NAS-FAL level indicated are active level
[0204] As shown in Table 7, both wetting surfactants significantly
improved phase stability over systems without the second wetting
surfactant component, with NAS-FAL providing the best phase
stability (e.g., 23-25 days at 50.degree. C.) with the least impact
on foam generation. The alkyl capped EO-PO surfactants outperform
PO-EO-PO and EO-PO-EO even without the second surfactant in the
sanitizing rinse aid compositions. The alkyl capped EO-PO
surfactants also outperform the PO-EO-PO (Pluronic 25R2) in
combination with the second surfactant (Novel). Systems with alkyl
capped antifoaming agents (Plurafac LF131) and NAS-FAL achieved the
greatest phase stability at 50.degree. C., but exhibited greater
amount of foam than systems using Plurafac SLF-180 as the
antifoaming surfactant. The results demonstrate that an alkyl
capped surfactant provides suitable peracid stability and
antifoaming properties, including shelf stability for at least one
year at room temperature. The results are further shown in FIG. 1,
wherein the foam performance at 122.degree. F. after storage at
104.degree. F. was evaluated using the various surfactants (FIG.
1). As shown in the figure the foam performance was measured at 13
days, 17 days, 25 days and 28 days.
Example 4
[0205] Sanitizing rinse aid compositions according to the invention
and resulting from the testing set forth in Example 2 were further
evaluated for water sheeting ability, spot free drying on wares,
and antimicrobial efficacy in solutions and also on surfaces. The
control for the rinse aid component of the sanitizing rinse aid
compositions was Apex RA (commercially-available rinse aid additive
from Ecolab, Inc.). The control rinse aid formulation includes a
combination of the following nonionic rinse aid surfactants, in
addition to various functional ingredients not contributing to
rinse aid performance: a block co-polymer comprised of
polypropoxylate (PO) and polyethoxylate (EO) units having the
following general structure POH--(PO)n-(EO)m-(PO)n-POH (Pluronic
25R2, manufactured by BASF, wherein n is an integer from 1-30, m is
an integer from 1-160); and an alcohol ethoxylate.
[0206] Sheeting performance was evaluated according to the ability
of a rinse aid to impart water sheeting on surfaces relevant to
commercial ware washing process. The test involves observation of
water sheeting on six different types of ware wash materials,
including: a china dinner plate, a melamine dinner plate, a glass
panel, a stainless steel panel, a stainless steel butter knife, and
a 10 oz. glass tumbler. The test materials are initially cleaned
and then soiled with a solution containing 0.2% hotpoint soil
(mixture of powdered milk and margarine). The materials are then
exposed to 30 second wash cycles using 160.degree. F. city water
(for high temperature evaluations) or 120.degree. and 140.degree.
F. city water (for low temperature evaluations). The test product
is measured in ppm actives. Immediately after the ware wash
materials are exposed to the test product, the appearance of the
water draining off of the individual test materials (sheeting) is
examined.
[0207] The machine employed is a warewashing machine with hot city
water connections and a tempered glass window for observing
sheeting on the test substrates. A trouble light is used to light
the interior of the warewashing machine so that the test substrates
can be easily observed for water sheeting. The warewashing machine
has controls for adjusting and maintaining a constant temperature
throughout the test. The six test substrates are evenly distributed
on a wash rack.
[0208] The results of these tests are shown in Table 8.
TABLE-US-00008 TABLE 8 ppm, Actives in Rinse Aid 60 70 80 90 100
110 120 130 A (13505-84-1 (15% Plurafac SLF-180, 0% Novel 1021 GB)
Polycarbonate Tile 1 1 1 1 1 1 1 (clear) New Glass tumbler 1 1 1 1
1 X X China Plate 1 1 1 1 1 X X Melamine Plate 1 1 1 1 1 X X
Polypropylene Cup 1 1 1 1 1 1 1 (yellow) Dinex Bowl (blue) 1 1 1 1
1 1 1 Polypropylene Jug 1 1 1 1 1 1 1 (blue) Stainless Steel 1 1 1
1 1 1 1 Knife Polypropylene tray 1 1 1 1 1 1 1 (peach) New
Fiberglass tray (tan) New 1 1 1 1 1 1 1 Stainless steel slide 316
New 1 1 1 1 X X X Temperature, .degree. F. 140.degree. F.
140.degree. F. 140.degree. F. 140.degree. F. 140.degree. F.
140.degree. F. 140.degree. F. Suds Trace Trace Trace 1/4'' 1/4''
1/4'' 1/4'' B (13505-84-5 (11% Plurafac SLF-180, 4% Novel 1021 GB)
Polycarbonate Tile 1 1 1 1 1 1 (clear) New Glass tumbler 1 1 1 1 1
1 1 China Plate 1 1 1 1 1 1 1 Melamine Plate 1 1 1 1 1 1 X X
Polypropylene Cup 1 1 1 1 1 1 1 (yellow) Dinex Bowl (blue) 1 1 1 1
1 Polypropylene Jug 1 1 1 1 1 1 1 (blue) Stainless Steel 1 1 1 1 1
1 1 1 Knife Polypropylene tray 1 1 1 1 1 1 1 (peach) New Fiberglass
tray (tan) New 1 1 1 1 1 1 1 Stainless steel slide 316 New 1 1 1 1
1 1 X X Temperature, .degree. F. 140.degree. F. 140.degree. F.
140.degree. 140.degree. F. 140.degree. F. 140.degree. F.
140.degree. F. 140.degree. F. Suds 1/8'' 1/4'' 1/4'' 1/2'' 1/2''
1/2'' 1/2- 3/4'' 3/4'' C (Control) Polycarbonate Tile 1 1 1 1 1 1 1
(clear) New Glass tumbler 1 1 1 1 1 1 1 China Plate 1 1 1 1 1 1 1
Melamine Plate 1 1 1 1 1 1 1 1 Polypropylene Cup 1 1 1 1 1 1 1
(yellow) Dinex Bowl (blue) 1 1 1 1 1 1 1 Polypropylene Jug 1 1 1 1
1 1 1 (blue) Stainless Steel 1 1 1 1 1 1 1 Knife Polypropylene tray
1 1 1 1 1 1 1 (peach) New Fiberglass tray (tan) New 1 1 1 1 1 1 1
Stainless steel slide 316 New 1 1 1 1 1 1 1 1 Temperature, .degree.
F. 140.degree. F. 140.degree. F. 140.degree. F. 140.degree. F.
140.degree. F. 140.degree. F. 140.degree. F. 140.degree. F. Suds
Trace Trace Trace Trace Trace Trace Trace Trace
[0209] As set forth above in Tables 8, "1" represents "pin point"
sheeting and an "X" corresponds to complete sheeting. Pinhole
Sheeting--refers to the appearance of tiny pinholes on the surface
of the water draining off of the ware wash material. These holes
increase slightly in size as the water continues to drain off. No
droplets should be left on the surface of the test material as the
water nears being completely drained. Upon drying, no spots are
left on the surface of the test pieces. Complete Sheeting--refers
to an unbroken sheet of water clinging to the surface of the test
material with no holes or breakage of the water surface as the
water continues to drain. There is actually a micro thin layer of
film on the water surface. As the water continues to drain, the
film layer squeezes closer and closer to the dish. Upon opening the
doors of the ware wash machine and exposing the dishes to the open
air, all test materials immediately flash dry (<30 seconds for
160.degree. F., <60 seconds for 120.degree. F.), and no spots
are left on the surface of the test materials.
[0210] As can be seen from these tables, the test formulations
achieved either pin point or complete sheeting on all substrates
whereas the comparative Control rinse aid composition, was only
able to achieve pin point sheeting in these experiments.
[0211] In addition to evaluating the substrates for water sheeting,
the level of foam present with each addition of rinse additive to
the water was observed. The foam level in the dish machine was also
noted. Foam levels of one-half inch or less are considered
acceptable.
Example 5
[0212] Spot and film accumulation on ware was also evaluated using
a ten-cycle spot and film test to assess the impact of rinse aids
on the amount of spots and film that appear on hydrophilic and
hydrophobic ware samples washed in an institutional type dish
machine in the presence of detergent and food soil.
[0213] The ware wash machine was filled with water and the hardness
was tested (17 gpg). The tank heaters were turned on and the ware
wash machine wash cycle and rinse cycle temperatures were selected.
The amount of detergent and food soil were weighed to charge the
sump to reach desired concentrations of 1200 ppm Apex Detergent and
2000 ppm food soil. The amounts of detergent and food soil were
weighted and put into 9 containers, respectively, in order to
compensate for the loss from rinse water after each cycle. Drinking
glasses, plastic tumblers, glass coupons and polycarbonate coupons
were placed in the rack according to the positions shown below for
6 glasses (1-6), 3 polycarbonate coupons (7-9), for drying
(residual water) 3 glasses (A-C), and 3 tumblers (D-F).
##STR00010##
[0214] The machine rinse pump was primed to the desired dosage of
rinse aid and the sump was primed with 1200 ppm detergent and 2000
ppm food soil. Put the rack in the ware wash machine for one cycle.
Food soil and detergent (one of the nine containers measured ahead
of time) was added after first cycle to compensate loss during the
rinse cycle. Controls were run with no rinse aid and with benchmark
rinse aid. Another cycle was started and repeated until ten cycles
have been run totally. Then the wares A-F were sealed back to each
plastic seal bag (where original pre-weights were obtained) and
each weighed separately. Wares/coupons were dried overnight and
then graded by image analysis and visual grading on spots and film.
The wares are evaluated for appearance by trained personnel and by
image analysis of digital photographs of the dried wares.
[0215] This test method was performed under conditions designed to
replicate both "dump and fill" and "recirculating" type dish
machines. The test formulation 13642-08-01 was compared to results
obtained with various commercial rinse aid controls designed for
each type of dish machine and water or water and chlorine bleach
controls. Visual assessment of the results for both the glasses and
plastic coupons treated with typical low temperature ware wash
sanitizing and bleach (Ultra San, Ecolab Inc.) and with the
sanitizing rinse aid composition 13642-08-01 (shown above in Table
4A) are provided in the grading results shown in FIGS. 3-4.
[0216] Image analysis data of film on glasses (FIG. 2A) and plastic
coupons (FIG. 2B) for sanitizing rinse composition and for control
samples using Apex Rinse Aid or Ultra San+Ultra dry. The image
analysis data of the glasses and plastic coupons are shown for the
glasses (FIG. 3A) and plastic coupons (FIG. 3B) for sanitizing
rinse composition and for control samples using Apex Rinse Aid or
Ultra San+Ultra dry.
Example 6
[0217] The antimicrobial efficacy of formulations according to
embodiments of the invention were measured by AOAC test method
960.09, with modifications set forth in the description of the
Example. The operating technique of the AOAC official method
(960.09) for evaluating the antimicrobial efficacy of a food
contact sanitizer requires 99 mL of the test biocide to be
dispensed into a sterile 250 mL Erlenmeyer flask and then placed in
a 77.degree. F. (25.degree. C.) water bath until it has temperature
equilibrated, or 20 minutes, before starting the micro evaluation.
The compositions described here are intended for use in mechanical
dish machines and will be used at temperatures of approximately
120.degree. F. to 140.degree. F. To ensure the sanitizing rinse aid
compositions according to the invention achieved required efficacy
at these elevated application temperatures, the above mentioned
food contact sanitizer method was modified to equilibrate 99 mL of
a use-solution to 120.degree. F., 130.degree. F. or 140.degree. F.
Further, it was determined that minimal exposure to heated diluent
was necessary to maintain an active level in solution high enough
to achieve appropriate efficacy in suspension.
[0218] The modified use-solution preparation procedure is outlined
herein: Test substance diluent was pre-heated and equilibrated to
the test temperature. Sanitizing rinse aid was diluted in DI water
to make a 1% (1.0 g/100 g total) stock solution. A stock solution
was considered necessary to deliver an accurate weight of chemistry
greater than 1 g per test flask. An appropriate amount of stock
solution to achieve a final use-solution concentration of 8.3 ppm
POOA was added to a 500 mL Erlenmeyer flask and diluted to a total
weight of 500 g by the pre-heated diluent. While mixing, 99 mL of
the sanitizing rinse aid use-solution were dispensed into three
separate 250 mL Erlenmeyer test flasks. All three test flasks were
placed in a test temperature equilibrated water bath at the same
time. Flask #1 was designated for monitoring temperature, as well
as use-solution active level. A thermometer was put in this flask
to observe the temperature of the use-solutions. Once the
temperature had reached the desired test temperature (.+-.1.degree.
C.), the micro suspension study began on the other two test flasks
(flasks #2 and #3) in the water bath. At the same time as the micro
study, an additional analyst titrated flask #1 for use-solution
active levels.
[0219] Antimicrobial efficacy data for lead sanitizing rinse aid
compositions are shown in the Tables 9A-D.
TABLE-US-00009 TABLE 9A (replicate 1) Avg. Log.sub.10 Targeted
Titrated Reduction Concentration Concentration Use-solution in 30
sec Formula ID (ppm POOA) (ppm POOA) Temperature (E. coli)
13642-08-01 8.3 ppm 9.5 ppm 118.4.degree. F. >7.03 Batch A 8.1
ppm 118.4.degree. F. >7.03 13642-08-01 7.41 ppm 119.5.degree. F.
>7.03 Batch B 8.6 ppm 117.9.degree. F. >7.03 13642-08-01 9.2
ppm 118.8.degree. F. >7.03 Batch C 7.8 ppm 118.6.degree. F.
>7.03
TABLE-US-00010 TABLE 9B (replicate 2) Avg. Log.sub.10 Targeted
Titrated Reduction Concentration Concentration Use-solution in 30
sec Formula ID (ppm POOA) (ppm POOA) Temperature (E. coli)
13642-08-01 8.3 ppm 7.81 ppm 118.4.degree. F. 6.93 Batch A 7.86 ppm
118.4.degree. F. >6.93 13642-08-01 5.85 ppm 119.5.degree. F.
5.76 Batch B 7.86 ppm 118.4.degree. F. 6.81 13642-08-01 7.74 ppm
118.6.degree. F. 6.49 Batch C 7.57 ppm 118.4.degree. F.
>6.93
TABLE-US-00011 TABLE 9C (Replicate #3*) Targeted Avg. Log.sub.10
Reduction Concentration Use-solution in 30 sec Formula ID (ppm
POOA) Temperature S. aureus E. coli 13642-08-01 8.3 ppm 120.degree.
F. >6.90 >7.08 Batch A 13642-08-01 >6.90 >7.08 Batch B
13642-08-01 >6.90 >7.08 Batch C *Performed by a second
analyst. Titrations of the use-solution were not performed in this
study; however the rest of the use-solution preparation method was
followed.
TABLE-US-00012 TABLE 9D (Replicate #4) Targeted Avg. Log.sub.10
Reduction Concentration Use-solution in 30 sec Formula ID (ppm
POOA) Temperature S. aureus E. coli 13642-08-01 8.3 ppm 140.degree.
F. >6.91 >7.11 Batch A 13642-08-01 >6.91 >7.11 Batch B
13642-08-01 >6.91 >7.11 Batch C
[0220] The data set forth in Table 9 shows that beneficially,
according to the invention, there is a demonstrated synergy between
the peroxycarboxylic acid antimicrobial efficacy and temperature,
wherein improved antimicrobial efficacy at elevated temperatures
allows formulation of a non-acidic peroxycarboxylic acid.
[0221] To further characterize the discovery that temperature
greatly impacts efficacy of POOA against gram negative
microorganisms such as E. coli, additional studies were performed
at temperatures below 120.degree. F. These data are collected in
Table 10 below.
TABLE-US-00013 TABLE 10 Use- Avg. Log.sub.10 Reduction
Concentration solution Test in 30 sec Formula ID (ppm POOA) pH
Temp. S. aureus E. coli 13505-84-4 15 ppm pH 7.30 77.degree. F.
>6.47 1.24 20 ppm pH 7.38 >6.47 2.71 9.8 ppm pH 7.48
100.degree. F. N/A >6.75 8.6 ppm pH 7.44 >6.75 9.8 ppm pH
7.48 110.degree. F. >6.75 8.6 ppm pH 7.44 >6.75
[0222] The efficacy against E. coli was significantly less at room
temperature than at increased temperatures of 100.degree. F. and
110.degree. F. Beneficially, the micro efficacy of the compositions
are suitable for use, for example, in mechanical dish machines
which are generally operated at temperatures of at least about
100.degree. F., at least about 120.degree. F. and/or at least about
140.degree. F. (including all ranges disposed therein between).
Use-solutions tested at elevated temperatures achieved complete
kill of E. coli within 30 seconds at approximately half the
concentration as room temperature tested use-solutions. These data
support a synergist effect of increased temperature in combination
with Sanitizing Rinse compositions described herein for efficacy at
a neutral pH against E. coli. It is unexpected according to the
invention that increasing temperature to at least about 100.degree.
F., at least about 110.degree. F. and/or at least about 120.degree.
F. overcomes peroxyoctanoic acid efficacy dependence on pH.
[0223] As one skilled in the art shall ascertain from the
disclosure of the invention, the sanitizing rinse aid compositions
are particularly suited for microbial efficacy, including for
example Gram negative pathogenic organisms, at temperatures of at
least about 100.degree. F., at least about 110.degree. F. and/or at
least about 120.degree. F. In some aspects, the contact time for
the sanitizing rinse aid composition is about 30 seconds (such as
shown in the examples using U.S. EPA regulatory requirements for
food contact sanitizing). However, in other aspects, the contact
time for obtaining the measured microbial efficacy is less, such as
about 15 seconds as may be applicable in various ware wash machines
and applications of use thereof. In still further aspects, the
contact time may be more than 15 seconds or more than 30 seconds
depending upon a particular application of use.
[0224] The inventions 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 inventions
and all such modifications are intended to be included within the
scope of the following claims.
* * * * *