U.S. patent application number 11/388553 was filed with the patent office on 2007-09-27 for stable aqueous suspension concentrate for delivery of uv-labile water-insoluble biocides.
Invention is credited to Xianbin Liu, Kolazi S. Narayanan, Karen Winkowski.
Application Number | 20070224135 11/388553 |
Document ID | / |
Family ID | 38533675 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070224135 |
Kind Code |
A1 |
Liu; Xianbin ; et
al. |
September 27, 2007 |
Stable aqueous suspension concentrate for delivery of UV-labile
water-insoluble biocides
Abstract
A stable, aqueous suspension concentrate which includes a solid
polymeric dispersant comprising one or more anionic polymeric
dispersing agents, optionally a co-dispersant which preferably is a
homopolymer and/or a copolymer of a heterocyclic vinyl lactam,
preferably in a wt. ratio of 0.1:1 to 1:0.1, a UV-labile,
water-insoluble biocide active, and a UV-blocker or UV-absorber to
stabilize said active upon storage and/or exposure to sunlight or
UV radiation.
Inventors: |
Liu; Xianbin; (Dubline,
CA) ; Winkowski; Karen; (Springfield, NJ) ;
Narayanan; Kolazi S.; (Wayne, NJ) |
Correspondence
Address: |
INTERNATIONAL SPECIALTY PRODUCTS
1361 Alps Road
Wayne
NJ
07470
US
|
Family ID: |
38533675 |
Appl. No.: |
11/388553 |
Filed: |
March 24, 2006 |
Current U.S.
Class: |
424/59 ; 514/373;
514/478 |
Current CPC
Class: |
A01N 47/12 20130101;
C09D 5/14 20130101; A01N 47/12 20130101; A61K 31/425 20130101; A01N
25/04 20130101; A01N 25/30 20130101; A61K 31/325 20130101; A01N
25/22 20130101; A01N 47/12 20130101; A01N 25/30 20130101; A01N
25/04 20130101; A01N 59/16 20130101; A01N 43/80 20130101; Y10T
428/31989 20150401; A01N 47/04 20130101; A01N 37/34 20130101; A01N
37/34 20130101; A01N 2300/00 20130101; A01N 47/04 20130101; A01N
47/12 20130101; A01N 43/653 20130101; A01N 43/80 20130101; A01N
43/653 20130101; A01N 43/653 20130101; A01N 47/12 20130101 |
Class at
Publication: |
424/059 ;
514/478; 514/373 |
International
Class: |
A61K 8/27 20060101
A61K008/27; A61K 8/29 20060101 A61K008/29; A61K 31/425 20060101
A61K031/425; A61K 31/325 20060101 A61K031/325 |
Claims
1. A stable, aqueous suspension concentrate which includes a solid
polymeric dispersant comprising one or more anionic polymeric
dispersing agents, a UV-labile, water-insoluble biocide active and
a UV-blocker or UV-absorber to stabilize said active upon storage
and/or exposure to sunlight or UV radiation.
2. A stable, aqueous suspension concentrate according to claim 1
wherein said solid polymeric dispersant further comprises a
co-dispersant.
3. A stable, aqueous suspension concentrate according to claim 2
wherein said co-dispersant is a homopolymer and/or copolymer of a
heterocyclic vinyl lactam.
4. A stable, aqueous suspension concentrate according to claim 2
wherein said anionic polymeric dispersing agent and said
co-dispersant are present in a wt. ratio of 0.1:1 to 1:0.1.
5. A stable, aqueous suspension concentrate according to claim 1
wherein said anionic polymeric dispersing agent is selected from
the group consisting of a sodium salt of alkyl vinyl ether/maleic
acid half ester copolymer, a lignosulfonate or metal salt thereof,
a sulfonated naphthalene/formaldehyde condensate, an
alpha-olefin/maleic acid copolymer, a polyacrylate and mixtures
thereof.
6. A stable, aqueous suspension concentrate according to claim 1
wherein said biocide is a fungicide.
7. A stable, aqueous suspension concentrate according to claim 6
wherein said biocide is a preservative.
8. A stable, aqueous suspension concentrate according to claim 6
wherein said fungicide is a halopropargyl compound, an
isothiazolone, a triazole, a phthalimide, a benzimidazole carbamate
or tetrachloroisophalonitrile.
9. A stable, aqueous suspension concentrate according to claim 1
wherein said biocide active is iodopropargyl butyl carbamate.
10. A stable aqueous suspension concentrate according to claim 7
wherein the said preservative is benzisothiazolone.
11. A stable, aqueous suspension concentrate according to claim 1
wherein said UV-blocker is titanium dioxide, zinc oxide, a
stilbene, a UV-blocking mineral, and mixtures thereof.
12. A stable, aqueous suspension concentrate according to claim 2
wherein said co-dispersant comprises a homopolymer or copolymer of
vinyl pyrrolidone and an ionic derivative of methyl vinyl
ether-maleic acid half-ester.
13. A stable, aqueous suspension concentrate according to claim 2
wherein said co-dispersant is a clay selected from naturally
occurring silicates, atta clay, bentonite, diatomaceous earth and
Montmorillonite.
14. A stable, aqueous suspension concentrate according to claim 1
which exhibits essentially no degradation on storage at 50.degree.
C. for 30 days, and substantially no discoloration or yellowing on
exposure to sunlight or UV-radiation.
15. A composition including the concentrate of claim 1.
16. A paint composition including the concentrate of claim 1.
17. A personal care composition including the concentrate of claim
1.
18. An article comprising a substrate coated with the suspension
concentrate of claim 1.
19. An article according to claim 18 wherein said substrate is
wood.
20. A stable, water dispersible solid comprising a solid polymeric
dispersant comprising one or more anionic polymeric dispersing
agents, a UV-labile, water-insoluble biocide active and a
UV-blocker or UV-absorber to stabilize said active upon storage
and/or exposure to sunlight or UV radiation.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to delivery systems for
water-insoluble active chemicals, and, more particularly, to a
stable aqueous suspension concentrate of a UV-labile,
water-insoluble biocide active concentrate to stabilize such
actives against the degradation effects of sunlight and
UV-radiation.
[0003] 2. Description of the Prior Art
[0004] Numerous delivery systems and formulations have been
proposed to provide aqueous dispersions of substantially
water-insoluble biocide active chemicals such as iodopropargyl
butyl carbamate (IPBC). For example U.S. Pat. No. 6,506,794
describes an aqueous dispersion of halopropargyl compounds and a
partially hydrolyzed polyvinyl alcohol. However, such active
dispersions are quite susceptible to degradation upon storage
and/or exposure to UV-radiation. In particular, the decomposition
of IPBC typically results in the formation of a yellow or brown
by-product. The compositions thus will be unsuitable for use in
certain systems in need of antimicrobial protection particularly
white aqueous paints.
[0005] Various methods and compositions have been described to
stabilize biocidal compositions containing IPBC, for example, using
UV absorbers and/or organic epoxides in a liquid vehicle, as shown
in U.S. Pat. Nos. 4,276,211; 4,552,885; 5,938,825; 6,059,991 and
6,140,370. U.S. Pat. No. 6,616,740 teaches on the use of various
glycol carriers for IPBC stabilization. However, none of these
disclosures provide a stable IPBC composition as an aqueous
dispersion free from yellowing on exposure to UV-radiation.
[0006] U.S. Pat. No. 6,156,803 discloses the use of a partially
neutralized alkyl vinyl ether-maleic acid half ester copolymer as a
dispersing agent for water-insoluble agriculturally active
chemicals. Published U.S. Patent Application US 2004/0024099 A1
describes an aqueous suspension concentrate for water insoluble
chemicals comprising a mixture of an anionic polymeric suspension
agent and a homo- and/or a co-polymer of a heterocyclic vinyl
lactam.
[0007] Accordingly, it is an object of this invention to provide a
stable, aqueous suspension concentrate of a UV-labile biocide
active for delivery of such active in stabilized form into
formulations and onto substrates.
[0008] A particular object herein is to provide such stable
concentrates which experience substantially no degradation or
coloration upon storage and/or exposure to sunlight or UV-radiation
while retaining its bioactivity.
SUMMARY OF THE INVENTION
[0009] What is described herein is a stable, aqueous suspension
concentrate which includes a solid polymeric dispersant comprising
one or more anionic polymeric dispersing agents, optionally a
co-dispersant which preferably is a homopolymer and/or a copolymer
of a heterocyclic vinyl lactam, preferably in a wt. ratio of 0.1:1
to 1:0.1, respectively, a UV-labile, water-insoluble biocide active
and a UV-blocker or UV-absorber to stabilize said active upon
storage and/or exposure to sunlight or UV-radiation.
[0010] Preferably the stable, aqueous suspension concentrate
includes a biocide which is a fungicide or preservative.
[0011] Most preferably the biocide is a halopropargyl compound, an
isothiazolone, a triazole, a phthalimide, benzimidazol carbamate or
tetrachloroisophalonitrile; more particularly, iodopropargyl butyl
carbamate (IPBC), benzisothiazolone (BIT), propiconazole,
N(trichloromethylthio)pthalimide, methyl benzimidazol-2-yl
carbamate or tetrachloroisophalonitrile.
[0012] The UV-blocker or absorber suitably is titanium dioxide,
zinc oxide, stilbenes, or UV-blocking minerals and mixtures
thereof. The UV-absorbers can be esters of aromatic or aliphatic
acids with appropriate substituents, aromatic ketones, triazines,
which usually are commercially available.
[0013] In one embodiment of the invention, the stable, aqueous
suspension concentrate includes a co-dispersant which comprises a
homopolymer or copolymer of vinyl pyrrolidone, and an anionic
dispersing agent which is an ionic derivative of methyl vinyl
ether-maleic acid half-ester.
[0014] A feature of the invention is that the suspension
concentrate exhibits essentially no degradation on storage at
50.degree. C. for 30 days, and substantially no discoloration or
yellowing on exposure to sunlight or UV-radiation.
[0015] The invention herein further comprises a composition which
includes the stable aqueous suspension concentrate, e.g. a paint
composition; or a coating composition, construction material like
concrete, bricks, asphalt, shingles, metals and the like; or a
personal care composition.
[0016] Another feature of the invention is the provision of an
article which comprises a substrate coated with the suspension
concentrate described alone; e.g. an article wherein said substrate
is wood.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The primary dispersant in the present solid polymeric
dispersant composition of the invention is an anionic polymeric
dispersant such as the sodium salt of alkyl vinyl ether/maleic acid
half-ester copolymer (Easy-Sperse.RTM.) (ISP), a lignosulfonate or
metal salt thereof, e.g. POLYFON.RTM. or REAX.RTM. (Westvaco); a
sulfonated naphthalene/formaldehyde condensate, e.g. MORWET.RTM.
(Witco); UFOXANE.RTM. or MARESPERSE.RTM. (Lignotech); an
alpha-olefin/maleic acid copolymer, a high molecular weight block
copolymer with pigment affinic groups, e.g., DISPERBYCK 190 (BYK
Chemie) or a polyacrylate, which is capable of dispersing
hydrophobic compounds in water, and mixtures thereof. Desirably the
monomer of the anionic polymer contains 1-4 anionic sites per mole
of repeat units.
[0018] The optional co-dispersant in the composition of the
invention is a vinyl lactam which is suitably the homopolymer of
vinyl pyrrolidone or vinyl caprolactam either optionally
substituted on the ring or in the vinyl group with a lower alkyl
(C.sub.1 to C.sub.4 alkyl), or a mixture of these homopolymers.
Alternatively, the co-dispersant can be a copolymer of vinyl
pyrrolidone and/or vinyl caprolactam, e.g. vinyl pyrrolidone/vinyl
caprolactam copolymer, vinyl pyrrolidone/vinyl acetate, vinyl
pyrrolidone/acrylic acid, vinyl pyrrolidone/acrylate, vinyl
pyrrolidone and butane, or a vinyl pyrrolidone and a
C.sub.14-C.sub.24 alpha-olefin. The vinyl lactam co-dispersant
generally has a weight average molecular weight of between about
5,000 and about 100,000 consistent with a Fikentscher K-value of
from about 10 to about 120. The codispersant can be a clay selected
from naturally occurring silicates, atta clay, bentonite,
diatomaceous earth, and Montmorillonite. In the solid dispersant
mixture, the lactam polymer can coil around and coat at least a
portion of an active water-insoluble ingredient thus reducing its
surface hydrophobicity while retaining the intrinsic hydrophobic
character of the insoluble active component. The lactam coating
also can associate with anions of the primary dispersant to provide
a composition of improved stability and permit high load active
compositions for disparate hydrophobic species which are not
otherwise suspendable. The use of the co-dispersant lactam polymer
in the invention solid mixture permits the use of a lower
concentration of the primary anionic polymeric dispersant component
which reduces irritant properties and/or foaming. Also the presence
of the lactam polymer in the solid mixture allows the use of
several otherwise incompatible anionic polymeric dispersants.
[0019] The active component of the invention compositions is a
particulate, substantially water-insoluble UV-labile biocide
compound, or a hydrophobic compound or mixture of such compounds,
and is preferably a biocide such as a halopropargyl compound, a
isothiazolone, a triazole, a phthalimide, a benzimidazole
carbamate, a tetrachloroisophalonitrile and the like.
[0020] Some of these biocide compounds usually exhibit significant
degradation upon certain storage conditions and/or exposure to
sunlight or UV-radiation accompanied by discoloration when used in
such products as in paint, wood or personal care formulations.
[0021] By the term "substantially insoluble", it is meant that for
all practical purposes, the solubility of the compound in water is
insufficient to make the compound practicably usable in a spray-on
or dip end use without some modification either to increase its
solubility or dispersability in water, so as to increase the
compound's bioavailability or avoid the use of excessively large
volumes of solvent. Compounds having low water solubility usually
include those having a solubility of less than 1 gram per 100 grams
of water at room temperature conditions.
[0022] Typical "substantially insoluble" biocides include:
Iodopropargyl butyl carbamate (IPBC), Benzisothiazolone (BIT),
Propiconazole, N(trichloromethylthio)pthalimide, methyl
benzimidazol-2-yl carbamate, tetrachloroisophalonitrile,
2-n-octyl-3-isothiazolone, Dibromonitriloproprianamide (DBNPA),
2-(thiocyanomethylthio)benzothiazole (TCMTB), Tebuconazole,
Tributyl tin benzoate, Parabens,
2,5-dimethyl-N-cyclohexyl-N-methoxy-3-furan carboxamide,
5-Ethoxy-3-trichloromethyl-1,2,4 thiadiazole, 3-(2-methyl
piperidino)propyl 3,4-dichlorobenzoate, N,N'-(1,4-piperazinediyl
bis(2,2,2-trichloro)ethylidene)bis formamide, Tetramethyl thiuram
disulfide, 0-Ethyl-S,S,diphenyl-dithiophosphate,
5,10-dihydro-5,10-dioxo
naphtho(2,3,9)-p-dithiin-2,3-dicarbonitrile,
.alpha.-2-[(4-chlorophenyl)ethyl]-.alpha.-(1,1-dimethyl ethyl)-1
H-1,2,4-triazole-1-ethanol 3-(3,4-dichlorophenyl)1,1 dimethylurea,
N-tridecyl-2,6-dimethylmorpholine and
4-N-dodecyl-2,6-dimethylmorpholine.
[0023] By the term "UV labile" is meant for all practical purposes,
the active ingredient is susceptible to absorption of any part of
natural sunlight or exposed artificial light. Generally, any active
ingredient containing Unsaturated moieties, especially with
conjugation, and aromatic or heterocyclic components, will be
subject to absorption of such radiation, which eventually can cause
a color change degradation or loss of activity.
[0024] In this invention, the term UV-blocker and/or UV-absorber
includes those compounds which will cause a considerable shift of
an appropriate active portion of the radiation spectral
component.
[0025] The instant invention provides a suspension concentrate
which is environmentally friendly, and free of organic solvents and
conventional emulsifiers. The aqueous suspension concentrate herein
can be formulated with multiple active ingredients to enhance its
spectrum of activity. The concentrate is easily dilutable with
water. A high salt content in the ground water from the field will
not affect its stability on dilution. The suspension concentrate
can be made easily by standard methods, as described below:
[0026] The commercial product Easy-Sperse.RTM. (International
Specialty Products Inc.) suitably is employed as the anionic
polymeric dispersant in the solid composition of the invention.
Easy-Sperse.RTM. is the partially neutralized (NaOH) aqueous
solution of methyl vinyl ether/maleic acid half-ester (ethyl/butyl)
copolymer having a solids content of about 25% and a viscosity of
about 6,000 cps.
[0027] The optional co-dispersant in the composition suitably is an
aqueous solution of polyvinyl pyrrolidone (20-40% solids). A
solution/slurry of both the primary and co-dispersant is provided
in a weight ratio of these ingredients of 0.1:1 to 1:0.1,
respectively, preferably 1:0.5 to 1:5, and, most preferably, 1:1 to
1:4. The solution/slurry may be diluted with water, if necessary,
to produce a viscosity particularly suitable for spray drying, e.g.
3,000 to 6,000 cps. Then the solution/slurry is spray dried
suitably at an inlet temperature of about 300-480.degree. F. and an
outlet temperature of about 150-270.degree. F. The product of the
spray drying process is a solid polymeric dispersant concentrate
suitable for delivery of UV-labile, water-insoluble biocide
actives. If, however, both the primary and co-dispersants are
commercially available as solids, then only simple granulation of
the ingredients is required to obtain the desired solid
concentrate.
[0028] The active material then can be added in a suitable amount
and processed, if desired, for water-sensitive actives, under
anhydrous conditions, and made into solid delivery systems such as
wettable powders, water dispersible granules and tablets. If
desired, the solid form can be used in an aqueous medium with water
of dilution, in an aqueous or suspension formulation. The
formulation also can be coated onto hydrophobic surfaces, or
printed onto sheets.
[0029] The products of the invention are advantageous from a
commercial standpoint for the following reasons. In particular the
suspension concentrate exhibits essentially no degradation on
storage at 50.degree. C. for 30 days, and substantially no
discoloration or yellowing on exposure to sunlight or
UV-radiation.
[0030] The solid composition of the invention also may be
efficiently prepared by simply homogenizing and wet-milling the
components or by extrusion. The composition may be diluted with a
desired amount of water by mixing in a high speed mixer for a
period of from about 30 minutes to 1 hour.
[0031] The composition of the present invention can incorporate up
to 90% of an active material in its mixture while retaining its
stability for at least 1 year or more. On dilution the active
component can have a concentration of 10 ppm to 50% in the diluted
mixture while retaining suspension stability for 4 hours or more.
The combination of the anionic dispersant with the lactam polymer
has a synergistic suspension effect in that the dispersing ability
of the sum of either component alone is markedly exceeded.
[0032] Having generally described the invention, reference is had
to the following examples which illustrate preferred embodiments
and comparisons of the present concentrate or formulation with
those of the prior art.
EXAMPLE 1
Preparation of Solid Polymeric Dispersant Concentrate of
Invention
[0033] 72 g of an Easy-Sperse.RTM. solution (24.8% solids) was
mixed with 176 g of PVP K-30 (30.5% solids), then homogenized at
room temperature for 1 hour and concentrated in a hood overnight at
room temperature followed by drying in a vacuum oven (<10 mm Hg)
at 80.degree. C. for 2 hours. The resulting solid product had a Tg
of 159.degree. C. and <1% bound water and a wt. ratio of
Easy-Sperse.RTM. to PVP of 1:3.
EXAMPLE2
Preparation of Solid Polymeric Dispersant Concentrate by Spray
Drying
[0034] 240 Kg of Easy-Sperse.RTM. solution (26% solids) and 720 Kg
of PVP K-30 (36.6% solids) were mixed and heated to 120.degree. F.
and then diluted with 600 lbs of water. The resulting solution was
fed into a commercial spray dryer with an inlet temperature of
410.degree. F. and an outlet temperature of 265.degree. F. A solid
was obtained in the form of a powder which passed through a 20 mesh
screen. 700 lbs of dry material was obtained with 7% total (bound)
water. The wt. ratio of Easy-Sperse.RTM. to PVP was 1:4.
EXAMPLE 3
[0035] Examples 1 and 2 were repeated at a wt. ratio of 1:1.
Similar results were obtained.
EXAMPLE 4
[0036] Examples 1 and 2 were repeated at a wt. ratio of 1:2.
Similar results were obtained.
EXAMPLE 5
[0037] Example 1 was repeated with solid Morwet.RTM. D-425 in place
of a solution of Easy-Sperse.RTM., and a solution of PVP to produce
a 1:1 wt. ratio solid.
EXAMPLE 6
[0038] Example 5 was repeated at a wt. ratio of 1:3 with similar
results.
EXAMPLE 7
[0039] Example 5 was repeated with solid Reax.RTM. 100M in place of
Morwet.RTM. D-425 with similar results.
EXAMPLE 8
[0040] Example 6 was repeated with solid Reax.RTM. 100M in place of
Morwet.RTM. D-425 with similar results.
EXAMPLE 9
[0041] Mixture of Solid Dispersant and Biocide Active
[0042] 700 g of commercial IPBC active was mixed with 80 g of the
polymeric dispersant of Example 2 and 220 g of commercially
available titanium dioxide in a V-blender. This solid premix was
used to formulate wettable powders, suspension concentrates,
water-dispersible granules and tablets of the active.
EXAMPLE 10
[0043] 700 g commercial BIT active was mixed with 80 g of the
polymeric dispersant of Example 2 and 220 g of commercially
available titanium dioxide in a V-blender. This solid premix was
used to formulate wettable powders, suspension concentrates,
water-dispersible granules and tablets of the active.
EXAMPLE 11
[0044] 300 g of commercial IPBC was mixed with 70 g of the
polymeric dispersant/binder composition of Example 6 and 100 g of
commercially available titanium dioxide in a V-blender. This charge
was used to produce extruded granules and tablets.
EXAMPLE 12
[0045] 100 g of the charge from Example 11 was made into a paste by
kneading with water (10-20 g) and was extruded in a laboratory
table top extruder at maximum speed. The extrudate was dried in an
oven at 70 C for a period of 8 hours. The extrudate was dispersible
in water at a use level concentration of IPBC of from 0.1% to
2.0%.
EXAMPLE 13
[0046] 50 g of the extrudate of Example 12 was mixed with 1.5 g of
cross-linked polyvinyl pyrrolidone (Polyclar.RTM. ATF) and several
tablets were made by compressing the powder in a laboratory tablet
press at a pressure of 2.5 tons. Each tablet weighed about 3 g,
containing approximately 1.86 g IPBC. Aqueous suspensions were made
by dispersing each tablet in 186 g water by mild agitation for
about 10 minutes, to produce a 1% IPBC suspension.
EXAMPLE 14
[0047] The following briefly describes the procedure used to
prepare suspension concentrates of biocides shown in the following
Examples 15A to 15D.
[0048] Compositions of biocide suspension concentrates in suitable
and preferred ranges by weight thus-prepared include: Active
ingredient: 5-50%; preferred range 10-40%; polymeric dispersant;
0.2-8%, preferred: 1-5%; UV-blocker: 0.2-20%, preferred: 2-10%;
thickener: 0.05-0.4%; preferred: 0.1-0.3%; wetting agent: 0-1.0%,
preferred: 0-0.5%; defoamer: 0.05-0.4%, preferred: 0.1-0.3%;
preservative: 0-0.5% preferred 0-0.2%; and water to 100%.
General Procedure:
[0049] In a vessel with Cowles mixer added about 80% of water
required, followed by wetting agent, dispersant, UV-blocker, and
active ingredient. Mixed at 500 rpm for 30 minutes. Defoamer and
thickener were added to the above mixture and remaining water, and
mixed at 2000 rpm for an additional 30 minutes. The charge was
pumped into a basket mill and milled to the selected particle size,
usually about 10 microns average particle size (a Hegman rating
between 6 and 7).
[0050] Thickeners used are usually commercially available water
soluble polymers that impart high viscosity when added at very low
concentrations, such as natural gums, carbohydrates like
Kelzan.RTM., synthetic polymers like Carbopol.RTM. (polyacrylates).
The wetting agents are used to reduce friction during high speed
grinding, usually low foaming organic liquids with a low dynamic
surface tension, e.g. Surfynol.RTM. series or N-octyl pyrrolidone.
Preservatives used are commercially available registered organic
compounds capable of controlling biological growth in aqueous
medium during a reasonable storage period of about 1-5 years, e.g.
Nuosept.RTM. series, Kathon.RTM., Proxel.RTM. and the like.
EXAMPLE 15 A
[0051] 1 Kg of an aqueous suspension concentrate was prepared using
about 200 g of commercially available IPBC, by the general
procedure described in Example 14. 220 g IPBC was mixed with 25 g
Easy-Sperse.RTM. P 20 polymeric dispersant and 600 g deionized
water. The charge was loaded in a blender at low speed followed by
high speed blending for a period of 30 minutes. During the blending
process, 1.0 g Surfynol.RTM. 104 E was added along with 1.0 g Sag
30. The charge was processed as in Example 14. The suspension
concentrate was then mixed with 122 g of 1% Keizan.RTM. stock
solution prepared separately, followed by addition of the remaining
quantity of water (53 g) to make up a 22% IPBC concentrate.
EXAMPLE 15 B
[0052] Example 15 A was repeated except that 50 g zinc oxide was
included in the initial solid mix with water and 3 g of make-up
water was used at the end instead of 53 g water.
EXAMPLE 15 C
[0053] Example 15 B was repeated except that titanium dioxide was
used in the place of zinc oxide.
EXAMPLE 15 D
[0054] Example 15 C was repeated using 400 g IPBC instead of 200 g
and 40 g Easy-Sperse.RTM. P 20 instead of 25 g and initial water
was 400 g instead of 600 g, and make-up water was 23 g.
EXAMPLE 15 E
[0055] Example 15 C was repeated except that Disperbyck 190 was
used in place of Easy-Sperse.
[0056] The suspension concentrates described in Example 15 A, 15 B,
and 15 C were evaluated for yellowing on exposure to UV-light. The
results are shown in Example 16. Examples 15 C and 15 E were
evaluated for accelerated storage stability. These results are
shown in Example 17. Example 15 D was evaluated as an additive in
paint. These results are shown in Example 18.
EXAMPLE 16
[0057] TABLE-US-00001 TABLE 1 Yellowing upon UV-light Exposure
Formulation Degree of Yellowing Formulation 15 A +++ Formulation 15
B + Formulation 15 C - "+" = yellowing; "-" = non-yellowing
EXAMPLE 17
Stability of IPBC in Aqueous Suspension Concentrate
[0058] The IPBC dispersion described in Example 15 C and 15 E was
heat aged for 30 days at 50.degree. C. The resultant IPBC levels
were determined by Reversed-Phase HPLC. The levels of IPBC detected
in Sample 15 C was 21.54.+-.0.06 which is the same level as the
sample analyzed at time zero, immediately after preparation of the
suspension concentrate. Levels of IPBC detected in Sample 15 E were
20.34.+-.0.2% which is the same level as the sample analyzed at
time zero.
EXAMPLE 18
[0059] The efficacy of the 40% IPBC suspension concentrate in
Example 15 D, was compared to that of a commercial IPBC formulation
comparable in strength following ASTM D5590 entitled "Determining
the Resistance of Paint Films and Related Coatings to Fungal
Defacement by Accelerated Four Week Agar Plate". The results are
shown in Table 2. Growth ratings were taken every 7 days, on a
scale of "0"to "10", where "0" corresponds to the complete absence
of fungal growth and "10" corresponds to the complete coverage by
fungus. The Mixed Inoculum contained the fungi Aspergillus niger
and Penicillium funiculosum. TABLE-US-00002 TABLE 2 Efficacy of
IBPC Aqueous Suspension Concentrate Mixed Inoculum % by Leached
Unleached Paint Wt. 1 2 3 4 1 2 3 4 White Exterior Susp. Conc. 0.6
0 0 0 1 0 0 0 0 Commercial 0.6 0 0 0 0 0 0 0 0 Control -- 5 9 10 10
3 3 3 5 Deep Tint Susp. Conc. 0.5 0 0 0 1 0 0 0 0 Commercial 0.5 0
0 0 1 0 0 0 0 Control -- 7 7 8 10 4 4 8 10
EXAMPLE19
[0060] 1 Kg of an aqueous suspension concentrate was prepared with
BIT following the procedure of Example 15 C.
EXAMPLE 20
[0061] The efficacy of the BIT dispersion described in Example 19
was compared to that of a commercial BIT formulation of similar
strength following ASTM D2574 entitled "Resistance of Emulsion
Paints in the Container to Attack by Microorganisms". Results are
shown in Table 3. Growth ratings were taken at day 1, 2, 3 and 6
after each bacterial challenge on a scale of "0" to "4", where "0"
corresponds to no growth, "1" is less than 10 cfu/ml, "2" is 11-100
cfu/ml; "3" is 101-1,000 cfu/ml and "4" is higher than 1,000
cfu/ml. The mixed bacterial inoculum consisted of Pseudomonas
aeruginosa, Enterobacter cloacae, Bacillus subtilis, Bacillus
megaterium and Bacillus licheniformis. Final concentration for
Challenge I was 1.52.times.10.sup.6 cfu/ml and for Challenge II,
1.56.times.10.sup.7 cfu/ml. TABLE-US-00003 TABLE 3 Efficacy of BIT
Aqueous Suspension Concentrate % by Challenge I Challenge II Paint
Wt. 1 2 3 6 1 2 3 6 Paint A Susp. Conc. 0.05 0 0 0 0 0 0 0 0
Commercial 0.05 0 0 0 0 0 0 0 0 Control -- 4 4 4 4 4 4 4 4 Paint B
Susp. Conc. 0.1 0 0 0 0 1 0 0 0 Commercial 0.1 0 1 0 0 0 0 0 0
Control -- 4 4 4 4 4 4 4 4
EXAMPLE 21
[0062] Example 15 was repeated using propiconazole instead of IPBC.
Similar results were obtained.
EXAMPLE 22
[0063] Example 19 was repeated using a combination of IPBC and
propiconazole in the weight ratio of 1:2. Similar results were
obtained.
EXAMPLE 23
[0064] Example 15 was repeated using Folpet instead of IPBC.
Similar results were obtained.
EXAMPLE 24
[0065] Example 15 was repeated using chlorothalonil. Similar
results were obtained.
[0066] While the invention has been described with particular
reference to certain embodiments thereof, it will be understood
that changes and modifications may be made which are within the
skill of the art.
* * * * *