COMPOSITION CONTAINING 1,2-DIBROMO-2,4-DICYANOBUTANE (DBDCB) AND ZINC PYRITHIONE (ZPT)
20170265466 · 2017-09-21
Assignee
Inventors
Cpc classification
C09D5/14
CHEMISTRY; METALLURGY
International classification
Abstract
A composition, characterized in that it comprises 1,2-dibromo-2,4-dicyanobutane (DBDCB) and zinc pyrithione (ZPT) as active components.
Claims
1. A composition comprising 1,2-dibromo-2,4-dicyanobutane (DBDCB) and zinc pyrithione (ZPT) as active components.
2. The composition as claimed in claim 1, wherein the DBDCB the ZPT are present in the composition at a weight ratio of DBDCB to ZPT of 100:1 to 1:100, preferably 50:1 to 1:50, particularly preferably 10:1 to 1:10, yet more preferably 4:1 to 1:4.
3. The composition as claimed in claim 1, further comprising at least one further biocidal active substance.
4. The composition as claimed in claim 3, wherein the at least one further biocidal active substance is selected from the group consisting of 1,2-benzisothiazol-3(2H)-one (BIT), iodopropargyl butylcarbamate (IPBC) and 2-n-octylisothiazolin-3-one (OIT).
5. The composition as claimed in claim 3, wherein the sum of DBDCB, ZPT and the at least one further biocidal active substance is 1 to 80 wt %, preferably 5 to 40 wt %, based on the total weight of the composition.
6. The composition as claimed in claim 1, further compromising at least one further added substance.
7. The composition as claimed in claim 6, wherein the at least one further added substance comprises at least zinc oxide (ZnO), preferably in a weight ratio of ZnO to the sum of the components DBDCB, ZPT and the at least one further biocidal active substance of 1:1 to 1:10.
8. The composition as claimed in claim 6, wherein the at least one further added substance comprises at least one auxiliary selected from the group consisting of surface-active substances, wetting agents, emulsifiers, dispersants, stabilizers, adhesives, thickeners, spreading agents, organic solvents, fragrances, colorants, antidusting agents, buffering substances, buffer systems, pH regulators, solid carriers and water, particularly preferably water.
9. The composition as claimed in claim 6, wherein the composition comprises 20 to 99 wt %, particularly preferably 60 to 95 wt %, of the at least one further added substance based on the total weight of the composition.
10. A process for producing the composition as claimed in claim 1, the process comprising mixing together DBDCB and ZPT, optionally with addition of at least one further biocidal active substance and optionally with addition of at least one further added substance.
11. A method for protection of industrial materials from attack and/or destruction by microorganisms using the composition according to claim 1, the method comprising applying the composition according to claim 1 on or in a mixture with the industrial materials.
12. The method as claimed in claim 11, wherein the method comprises providing the composition in relation to the industrial material in amounts of 0.01 to 5 wt %, particularly preferably from 0.05 to 1.0 wt %, based on the weight of the material to be protected.
13. An industrial material, comprising the composition as claimed in claim 1.
14. The industrial material according to claim 13, wherein: the composition as claimed in claim 1 is mixed into the industrial material; and/or the industrial material is treated with the composition as claimed in claim 1.
15. The industrial materials as claimed in claim 14, wherein the industrial materials are aqueous-based coatings, paints and renders, chemical products for building and construction, for example bitumen emulsions or sealing compounds, auxiliaries for the leather or textile industry, glues and adhesives based on known raw materials of animal, vegetable or synthetic origin, polymer dispersions based on for example polyacrylate, polystyrene acrylate, styrene-butadiene, polyvinyl acetate and/or chemical industry precursors and intermediates in colorant production and colorant storage.
16. The composition as claimed in claim 1, wherein at least 60 wt %, particularly preferably at least 80 wt %, very particularly preferably at least 90 wt %, yet more preferably at least 95 wt %, of the sum of the active components DBDCB and ZPT are present in the composition in dissolved form.
17. The composition as claimed in claim 1, wherein the composition contains no further biocidal active substance, and the sum of the DBDCB and the ZPT is 1 to 80 wt %, based on the total weight of the composition.
18. The composition as claimed in claim 17, further comprising at least zinc oxide, in a weight ratio of ZnO to the sum of the components DBDCB, ZPT of 1:1 to 1:10.
19. A biocidal composition comprising a synergistic mixture of 1,2-dibromo-2,4-dicyanobutane (DBDCB) and zinc pyrithione (ZPT) as active components, wherein the 1,2-dibromo-2,4-dicyanobutane (DBDCB) and zinc pyrithione (ZPT) are present in the mixture in synergistically effective amounts.
20. The biocidal composition according to claim 19, wherein the composition is biocidally active against: Alcaligenes, Bacillus, Enterobacter, Escherichia, Proteus, Pseudomonas, Serratia, and Staphylococcus bacteria; Candida, Geotrichum, Rhodotorula, and Saccharomyces yeasts; and Acremonium, Alternaria, Aspergillus, Chaetomium, Fusarium, Lentinus, Paecilomyces, Penicillium, and Trichoderma fungi.
Description
EXAMPLES
[0108] The synergism of the composition according to the invention is demonstrated hereinbelow by way of example against certain germs that are particularly relevant in practice, for example Pseudomonas aeruginosa (example 1).
[0109] The observed synergism of the composition according to the invention may be determined by the following mathematical formula (cf. F. C. Kul, P. C. Elisman, H. D. Sylwestrowicz, P. K. Mayer, Appl. Microbiol. 9, p. 538 (1961):
where: [0110] Q.sub.a=the amount of component A in the active substance mixture which achieves the desired effect, i.e. no microbial growth, [0111] Q.sub.A=the amount of component A which, when used on its own, suppresses the growth of the microorganisms, [0112] Q.sub.b=the amount of component B in the active substance mixture which suppresses the growth of the microorganisms,
and [0113] Q.sub.B=the amount of component B which, when used on its own, suppresses the growth of the microorganisms.
[0114] A synergistic index obtained according to the above formula of SI<1 indicates a synergistic effect for the active substance mixture. The smaller the SI, the greater the synergistic effect.
[0115] The synergistic activity enhancement is elucidated by way of example but not by way of limitation with reference to the examples and calculations which follow.
Example 1: Synergism Toward Pseudomonas Aeruginoasa
[0116] The minimum inhibitory concentration of the inventive compositions listed in table 1 were investigated using the test germ Pseudomonas aeruginoasa.
TABLE-US-00001 TABLE 1 no. DBDCB:ZPT DBDCB [ppm], Q.sub.a ZPT [ppm],Q.sub.b SI 1 8:2 200 50 0.91 2 6:4 45 30 0.68 3 5:5 37.5 37.5 0.65 4 4:6 30 45 0.72 5 2:8 10 40 0.57 6 1:9 7.5 67.5 0.93 (test germ: Pseudomonas aeruginosa, Q.sub.A = 250 ppm of DBDCB, Q.sub.B = 75 ppm of zinc pyrithione)
[0117] In certain concentration ratios the inventive compositions show a distinct synergistic effect against the test germ Pseudomonas aeruginoasa.
Example 2: Synergism Toward Enterobacter aerogenes
[0118] The minimum inhibitory concentration of the inventive compositions listed in table 2 were investigated using the test germ Enterobacter aerogenes.
TABLE-US-00002 TABLE 2 no. DBDCB:ZPT DBDCB [ppm], Q.sub.a ZPT [ppm], Q.sub.b SI 1 9:1 78 9 0.96 2 6:4 30 20 0.90 3 5:5 25 25 0.75 4 4:6 20 30 0.80 5 2:8 10 40 0.82 (test germ: Enterobacter aerogenes, Q.sub.A = 100 ppm of DBDCB, Q.sub.B = 50 ppm of zinc pyrithione)
[0119] In certain concentration ratios the inventive compositions show a distinct synergistic effect against the test germ Enterobacter aerogenes.
Example 3: Synergism Toward Rhodotorula mucliaginosa
[0120] The minimum inhibitory concentration of the inventive compositions listed in table 3 were investigated with the test germ Rhodotorula mucilaginosa.
TABLE-US-00003 TABLE 3 no. DBDCB:ZPT DBDCB [ppm], Q.sub.a ZPT [ppm], Q.sub.b SI 1 9:1 22.5 2.5 0.55 2 8:2 20 5 0.60 3 6:4 15 10 0.70 4 5:5 12.5 12.5 0.75 5 4:6 10 15 0.80 6 2:8 5 20 0.90 7 1:9 2.5 22.5 0.95 (test germ: Rhodotorula mucilaginosa, Q.sub.A = 50 ppm of DBDCB, Q.sub.B = 25 ppm of zinc pyrithione)
[0121] In certain concentration ratios the inventive compositions show a distinct synergistic effect against the test germ (yeast) Rhodotorula mucilaginosa.
Example 4: Microbiological Stress Test—Preservation of a Polymer Emulsion
[0122] The preserving effect of an inventive composition comprising DBDCB and ZPT in a polymer emulsion (acrylate-based, pH=6.5) was investigated using a microbiological stress test.
[0123] The microbiological stress test examines the susceptibility of water-based systems to microbial attack and the effect of preservatives. To this end, the preservatives are incorporated in defined concentrations into the water-based systems. After the preparations have been completed, contamination with microorganisms of a defined type is effected at weekly intervals over a test period of 3 to not more than 6 weeks. 2-3 days and 7 days after each contamination, germ number determination is used to establish whether a complete kill or at least propagation inhibition of the introduced microorganisms compared to the unreserved control samples has been achieved.
[0124] Having knowledge of the microorganism populations prevalent in polymer emulsions and dispersions the experiment employed a mixture of the following microorganism types for testing:
[0125] Bacteria: Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus.
[0126] Molds: Acremonium strictum, Aspergillus niger and Geotrichum candidu.
[0127] Yeasts: Candida albicans and Rhodotorula rubra.
[0128] Very good activity is achieved when the preserved samples achieve a complete kill (0 bacteria/mold/yeast cells per g) of the introduced microorganisms (score of 3=very good).
[0129] The effect is deemed good when compared to the unpreserved sample (so-called reference sample) a markedly reduced microbe level is observed (10.sup.3-10.sup.1 bacteria/10.sup.2-10.sup.1 mold/yeast cells per g) (score of 2-good).
[0130] The effect is deemed fair when compared to the unpreserved sample a mildly reduced microbe level is observed (10.sup.4-10.sup.3 bacteria/10.sup.3-10.sup.2 mold/yeast cells per g) (score of 1=fair).
[0131] The effect is deemed poor when compared to the unpreserved sample no reduction or only a minor reduction of the microbe level is observed (residual level of at least 10.sup.5 bacteria/10.sup.4 mold/yeast cells per g) (score of 0=poor). The results achieved are shown in table 4:
TABLE-US-00004 TABLE 4 Activity of the biocides determined 1 week after germ addition in each case Biocide added [wt %] week week week week week week M 1 2 3 4 5 6 0.025% B 0 0 0 0 0 0 DBDCB S 0 0 0 0 0 0 H 0 0 0 0 0 0 0.050% B 0 0 0 0 0 0 DBDCB S 0 0 0 0 0 0 0 0 0 0 0 0 0.05% B 0 0 0 0 0 0 ZPT S 2 2 2 2 2 2 H 2 2 2 2 2 2 0.01% B 2 2 2 2 2 2 DBDCB + S 2 2 2 2 2 2 0.01% ZPT H 2 2 2 2 2 2 (M = microorganism, B = bacteria, S = molds, H = yeasts)
[0132] Addition of an inventive composition comprising DBDCB and ZPT achieves effective preservation despite a markedly reduced active substance amount compared to the respective individual active substances, i.e. good activity is observed against all microorganism types employed for testing.