COMPOSITION CONTAINING 1,2-DIBROMO-2,4-DICYANOBUTANE (DBDCB) AND AT LEAST ONE ORGANIC ACID AND/OR THE DERIVATIVES THEREOF

Abstract

A composition, characterized in that it comprises 1,2-dibromo-2,4-dicyanobutane (DBDCB) and at least one organic acid and/or the derivatives thereof.

Claims

1. A biocidal composition comprising: 1,2-dibromo-2,4-dicyanobutane (DBDCB); and an organic acid and/or an organic acid derivative.

2. The composition as claimed in claim 1, wherein a weight ratio of the DBDCB to the organic acid and/or the organic acid derivative is 99:1 to 1:99.

3. The composition as claimed in claim 1, wherein the organic acid and/or the organic acid derivative is selected from the group consisting of mono- and polycarboxylic acids and the derivatives thereof.

4. The composition as claimed in claim 1, wherein the organic acid and/or the organic acid derivative is salicylic acid and/or the derivatives thereof and is in the form of a composition SA which comprises at least 10 wt %, based on the total weight of the composition SA, of salicylic acid and/or the derivatives thereof.

5. The composition as claimed in claim 4, wherein the composition SA is a Salix alba extract.

6. The composition as claimed in claim 5, wherein the Salix alba extract is an extract from the bark of the white willow.

7. The composition as claimed in claim 1, further comprising at least one further biocidal active substance.

8. The composition as claimed in claim 1, wherein the sum of the weights of DBDCB, of the at least one organic acid and/or the derivative thereof, and of the additionally no further biocidal active substance or at least one further biocidal active substance is 1 to 80 wt %, preferably 5 to 60 wt % of the total weight of the composition.

9. The composition as claimed in claim 1, the organic acid derivatives are alkali metal salts of organic acids, preferably selected from the group consisting of sodium, potassium and lithium salts.

10. The composition as claimed in claim 1, further comprising at least one further added substance 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 at least one organic solvent, very particularly preferably at least one glycol.

11. The composition as claimed in 10, wherein the composition comprises 20 to 99 wt %, preferably 40 to 95 wt %, of the at least one further added substance, based on the total weight of the composition.

12. A process for producing the composition as claimed in claim 1, the process comprising mixing the DBDCB and the organic acid and/or organic acid derivative, optionally with addition of at least one further biocidal active substance and optionally with addition of at least one further added substance.

13. A method for protection of industrial materials from attack and/or destruction by microorganisms, the method comprising treating the industrial materials with the composition as claimed in claim 1.

14. An industrial material treated with the composition as claimed in claim 1.

15. An industrial material comprising a composition as claimed in claim 1.

16. The composition as claimed in claim 1, wherein a weight ratio of the DBDCB to the organic acid and/or organic acid derivatives is 9:1 to 1:9.

17. The composition as claimed in claim 1, wherein the organic acid and/or organic acid derivative is selected from the group consisting of benzoic acid, lactic acid, salicylic acid, sorbic acid, citric acid, and the derivatives thereof.

18. The composition as claimed in claim 1, wherein the organic acid and/or organic acid derivative is salicylic acid and/or the derivatives thereof and is in the form of a composition SA which comprises at least 75 wt %, based on the total weight of the composition SA, of salicylic acid and/or the derivative thereof.

19. The composition as claimed in claim 18, wherein the composition SA is a Salix alba extract from the bark of the white willow, extracted with water and/or ethanol.

20. The composition as claimed in claim 1, wherein: a weight ratio of the DBDCB to the organic add and/or the organic acid derivative is 9:1 to 1:9; the organic acid and/or the organic acid derivative is salicylic acid and/or derivatives thereof and is in the form of a composition SA which comprises a Salix alba extract from the bark of the white willow, wherein the Salix alba extract comprises at least 50 wt %, based on the total weight of the composition SA, of the salicylic acid and/or the derivatives thereof; the composition further comprises at least one further biocidal active substance selected from the group consisting of 1,2-benzisothiazol-3(2H)-one (BIT), benzyl alcohol, benzyl hemiformal, 2-bromo-2-nitropropane-1,3-diol (Bronopol), 5-chloro-2-methyl-4-isothiazolin-3-one/2-methyl-4-isothiazolin-3-one (CMIT/MIT), 2,2-dibromo-3-nitrilopropionamide (DBNPA), diazolidinyl urea, 3,3-dimethylol-5,5-dimethylhydantoin (DMDMH), dichlorobenzyl alcohol, didecyldimethylammonium chloride, dimethylolhydantoin, dodecylguanidine hydrochloride, imidazolidinyl urea, iodopropargyl butylcarbamate (IPBC), 2-n-octylisothiazolin-3-one (OIT), phenoxyethanol, phenoxypropanol, phenylethyl alcohol, o-phenylphenol (OPP), poly(hexamethylenebiguanide) hydrochloride (PHMB), tetramethylolacetylene diurea (TMAD); the weight ratio of the at least one further biocidal active substance to the sum of DBDCB and the organic acid and/or the organic acid derivative is 1:40 to 1:1; the sum of the weights of DBDCB, of the at least one organic acid and/or the derivative, and of at least one further biocidal active substance is 5 to 60 wt of the total weight of the composition; the organic acid derivatives are alkali metal salts of organic acids selected from the group consisting of sodium, potassium and lithium salts; and the composition additionally comprises, based on the total weight of the composition, 40 to 95 wt % of at least one glycol.

Description

EXAMPLES

[0119] The synergism of the composition according to the invention is demonstrated hereinbelow by way of example against certain pathogens that are particularly relevant in practice, for example Pseudomonas aeruginosa, Staphylococcus aureus, Alternaria alternata or Geotrichum candidum.

[0120] The observed synergism of the compositions according to the invention may be determined by the following mathematical formula (cf. F. C. Kull, P. C. Elisman, H. D. Sylwestrowicz, P. K. Mayer, Appl. Microbiol. 9, 1961, page 538:

[00001]$\mathrm{synergistic}.Math..Math.\mathrm{index}\left(S.Math..Math.I\right)=\frac{Q_a}{Q_A}+\frac{Q_b}{Q_B}$ [0121] where: [0122] Q.sub.a=the amount of component A in the active substance mixture which achieves the desired effect, i.e. no microbial growth, [0123] Q.sub.A=the amount of component A which, when used on its own, suppresses the growth of the microorganisms, [0124] Q.sub.b=the amount of component B in the active substance mixture which achieves the desired effect, i.e. no microbial growth, [0125] and [0126] Q.sub.B=the amount of component B which, when used on its own, suppresses the growth of the microorganisms.

[0127] 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.

[0128] 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

[0129] Using various test pathogens, the minimum inhibitory concentration was determined and, on the basis thereof with the aid of the formula by F. C. Kull et al., the synergistic effects of the listed compositions according to the invention were calculated.

[0130] Compositions Comprising DBDCB and Citric Acid

TABLE-US-00001 TABLE 1 (test pathogen: Staphylococcus aureus): DBDCB:citric acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] Q.sub.b citric acid [ppm] SI 1 9:1 45 5 0.90 2 8:2 40 10 0.80 3 7:3 35 15 0.70 (test pathogen: Staphylococcus aureus => Q.sub.A = 50 ppm of DBDCB, Q.sub.B = 3001 ppm or citric acid)

[0131] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Staphylococcus aureus.

TABLE-US-00002 TABLE 2 (test pathogen: Alternaria alternata): DBDCB:citric acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] Q.sub.b citric acid [ppm] SI 1 9:1 22.5 2.5 0.90 2 8:2 20 5 0.80 3 7:3 17.5 7.5 0.70 (test pathogen: Alternaria alternata => Q.sub.A = 25 ppm of DBDCB, Q.sub.B = 3001 ppm of citric acid)

[0132] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Alternaria alternata.

TABLE-US-00003 TABLE 3 (test pathogen: Geotrichum candidum): DBDCB:citric acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] Q.sub.b citric acid [ppm] SI 1 9:1 90 10 0.90 2 8:2 80 20 0.81 3 7:3 35 15 0.35 (test pathogen: Geotrichum candidum => Q.sub.A = 100 ppm of DBDCB, Q.sub.B = 3001 ppm of citric acid)

[0133] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Geotrichum candidum.

[0134] Compositions comprising DBDCB and Lactic Acid

TABLE-US-00004 TABLE 4 (test pathogen: Pseudomonas aeruginosa): DBDCB:lactic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] Q.sub.b lactic acid [ppm] SI 1 9:1 450 50 0.92 2 8:2 400 100 0.83 3 7:3 350 150 0.75 4 6:4 300 200 0.67 (test pathogen: Pseudomonas aeruginosa => Q.sub.A = 500 ppm of DBDCB, Q.sub.B = 3001 ppm of lactic acid)

[0135] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Pseudomonas aeruginosa.

TABLE-US-00005 TABLE 5 (test pathogen: Alternaria alternata): DBDCB:lactic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] Q.sub.b lactic acid [ppm] SI 1 9:1 22.5 2.5 0.90 2 8:2 20 5 0.80 3 7:3 17.5 7.5 0.70 4 6:4 15 10 0.60 5 5:5 12.5 12.5 0.50 6 4:6 10 15 0.40 7 3:7 15 35 0.61 8 2:8 15 60 0.62 9 1:9 10 90 0.43 (test pathogen: Alternaria alternata => Q.sub.A = 25 ppm of DBDCB, Q.sub.B = 3001 ppm of lactic acid)

[0136] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Alternaria alternata.

[0137] Compositions Comprising DBDCB and Salicylic Acid

TABLE-US-00006 TABLE 6 (test pathogen: Pseudomonas aeruginosa): DBDCB:salicylic acid Q.sub.b salicylic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] [ppm] SI 1 9:1 225 25 0.91 2 8:2 200 50 0.82 3 7:3 175 75 0.72 4 6:4 150 100 0.63 5 4:6 200 300 0.90 6 3:7 150 350 0.72 (test pathogen: Pseudomonas aeruginosa Q.sub.A = 250 ppm of DBDCB, Q.sub.B = 3001 ppm of salicylic acid)

[0138] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Pseudomonas aeruginosa.

TABLE-US-00007 TABLE 7 (test pathogen: Alternaria alternata): DBDCB:salicylic acid Q.sub.b salicylic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] [ppm] SI 1 9:1 22.5 2.5 0.91 2 8:2 20 5 0.81 3 7:3 17.5 7.5 0.72 4 4:6 20 30 0.86 5 3:7 15 35 0.87 6 2:8 15 60 0.72 (test pathogen: Alternaria alternate => Q.sub.A = 25 ppm of DBDCB, Q.sub.B = 500 ppm of salicylic acid)

[0139] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Alternaria alternata.

[0140] Compositions Comprising DBDCB and Benzoic Acid

TABLE-US-00008 TABLE 8 (test pathogen: Bacillus subtilis): DBDCB:benzoic acid Q.sub.b benzoic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] [ppm] SI 1 9:1 22.5 2.5 0.90 2 8:2 20 5 0.80 3 7:3 17.5 7.5 0.70 4 6:4 22.5 15 0.91 5 5:5 25 25 1.01 6 4:6 20 30 0.81 7 3:7 15 35 0.61 8 2:8 20 80 0.83 (Q.sub.A = 25 ppm of DBDCB, Q.sub.B = 3000 ppm of benzoic acid)

[0141] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Bacillus subtilis.

TABLE-US-00009 TABLE 9 (test pathogen: Aspergillus brasiliensis): DBDCB:benzoic acid Q.sub.b benzoic acid No. [wt %/wt %] Q.sub.a DBDCB [ppm] [ppm] SI 1 9:1 225 25 0.93 2 8:2 200 50 0.85 3 7:3 175 75 0.78 4 6:4 150 100 0.70 5 5:5 125 125 0.63 6 4:6 100 150 0.55 7 3:7 150 350 0.95 8 2:8 100 400 0.80 9 1:9 50 450 0.65 (Q.sub.A = 250 ppm of DBDCB, Q.sub.B = 1000 ppm of benzoic acid)

[0142] In certain concentration ratios, the inventive compositions show a distinct synergistic effect against the test pathogen Aspergillus brasillensis.

Example 2: Microbiological Load TestPreservation of a Dishwashing Liquid

[0143] The preserving effect of an inventive composition comprising DBDCB and Salix alba extract in a dishwashing liquid was investigated using a microbiological load test.

[0144] The microbiological load test examines the susceptibility of water-based products 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, repeated contamination with microorganisms of a defined species and in defined amounts 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, microbial count is determined to establish whether complete elimination or at least inhibition of propagation of the introduced microorganisms compared to the unpreserved control sample has been achieved.

[0145] With knowledge of the microorganism populations prevalent in detergents of the type described here, the experiment employed a mixture of the following microorganism species for testing:

[0146] Bacteria: Escherichia coil, Pseudomonas aeruginosa, Staphylococcus aureus, Pseudomonas putida, Enterobacter gergoviae

[0147] Molds: Acremonium strictum, Aspergillus niger and Geotrichum candidum.

[0148] Yeasts: Candida albicans and Rhodotorula rubra.

[0149] Very good activity is achieved when there is complete elimination (0 bacteria/mold cells/yeast cells per g) of the introduced microorganisms in the preserved samples (score of 3=very good).

[0150] The activity is deemed good when a markedly reduced microbe level is observed (10.sup.3-10.sup.1 bacteria/10.sup.2-10.sup.1 mold cells/yeast cells per g) in the preserved samples compared to the unpreserved sample (so-called reference sample) (score of 2=good).

[0151] The activity 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 cells/yeast cells per g) (score of 1=fair).

[0152] The activity 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 cells/yeast cells per g) (score of 0=poor). The results achieved are shown in table 10.

[0153] The following compositions were used in the experiments depicted in table 10: [0154] A: DBDCB [0155] B: Composition comprising 25 wt % of Salix alba extract (comprising 80 wt % of salicylic acid) and 75 wt % of 1,2-propanediol. [0156] C: Composition comprising 20 wt % of DBDCB, 20 wt % of Salix alba extract (comprising 80 wt % of salicylic acid) and 60 wt % of 1,2-propanediol (inventive).

TABLE-US-00010 TABLE 10 Activity of the biocides in a dishwashing liquid, determined in each case 1 week after pathogen addition Biocide Composition added Week used [wt %] 1 2 3 4 5 6 A DBDCB [0.05] B 1 0 0 0 0 0 M 3 3 0 0 0 0 Y 3 3 0 0 0 0 B Salicylic acid B 1 0 0 0 0 0 [0.02] M 1 1 0 0 0 0 Y 1 0 0 0 0 0 C DBDCB [0.02] B 3 3 3 3 3 3 and M 1 3 3 3 3 3 salicylic acid Y 3 3 3 3 3 3 [0.016] (B = bacteria, M = molds, Y = yeasts) 3 = very good activity 2 = good activity 1 = fair activity 0 = poor activity

[0157] Adding an inventive composition comprising DBDCB and Salix alba extract comprising 80 wt % of salicylic acid achieves very good preservation activity despite a markedly reduced amount of active substance compared to the individual active substance DBDCB, i.e. all microorganism species used for testing are eliminated by the inventive mixture.