N-alkyl-lactams as crystallization inhibitors

In the spraying of an aqueous liquor comprising at least one of 1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol and 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-butan-2-ol, the improvement which comprises including in the liquor an N-alkyl-lactam of the formula ##STR1## in which R represents alkyl having 8 to 18 carbon atoms and PA1 n represents the numbers 3, 4 or 5,

The present invention relates to the new use of N-alkyl-lactams for 
preventing crystallization during application of aqueous spray liquors 
based on certain fungicidal active compounds. 
Spray apparatuses which are usually employed for applying aqueous 
formulations of plant treatment agents contain several filters and 
nozzles. Thus, for example, there are suction filters between the suction 
component and tank pump, and furthermore pressure filters positioned in 
the pressure region downstream of the pump. Nozzle filters can also be 
present directly before the spray nozzles. All of these filters and the 
nozzles may be blocked to a greater or lesser extent by active compound 
which crystallizes out during application of aqueous spray liquors based 
on solid active compounds. 
It has already been disclosed that 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
and 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-butan-2-ol 
have a fungicidal action and can be applied in the form of aqueous spray 
liquors to plants and/or their environment (compare EP-OS (European 
Published Specification) 0,040,345 and German Patent Specification 
2,324,010). Surface-active substances, such as, for example, alkylaryl 
polyglycol ethers, can be employed for the preparation of such spray 
liquors. However, a disadvantage of using these conventional formulations 
is that the active compounds tend to crystallize and can block both 
filters and nozzles of the spray apparatuses. 
It has now been found that N-alkyl-lactams of the formula 
##STR2## 
in which R represents alkyl having 8 to 18 carbon atoms and 
n represents the numbers 3, 4 or 5, can be used during application of 
aqueous spray liquors containing 
A) 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
of the formula 
##STR3## 
and/or 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-butan-2-ol 
of the formula 
##STR4## 
and 
B) if appropriate one or more other active compounds and additives, 
for preventing crystallization of the active compounds of the formulae (II) 
and/or (III). 
It is to be described as exceptionally surprising that the tendency of 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
and 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-butan-2-ol to 
crystallize can be greatly reduced by the use according to the invention 
of N-alkyl-lactams of the formula (I). Above all, it was not to be 
expected that N-alkyllactams of the formula (I) are considerably more 
suitable for the purpose stated than other substances of a comparable 
action. 
The use of N-alkyl-lactams of the formula (I) in aqueous formulations based 
on the fungicidal active compounds of the formulae (II) and/or (III) has a 
number of advantages. Thus, the N-alkyl-lactams of the formula (I) are 
substances which can be handled without problems and are also available in 
relatively large amounts. Furthermore, the use of the substances of the 
formula (I) prevents blocking of both the filters and the nozzles of the 
spray apparatuses on spraying aqueous formulations containing active 
compounds of the formulae (II) and/or (III). It is also advantageous that 
N-alkyl-lactams of the formula (I) display no undesirable side effects at 
all in plant protection. 
Formula (I) provides a general definition of the N-alkyl-lactams which can 
be used according to the invention. Substances of the formula (I) which 
can preferably be used are those in which 
R represents alkyl having 8 to 14 carbon atoms and 
n represents the numbers 3, 4 or 5. 
Substances of the formula (I) which can particularly preferably be used are 
those in which 
R represents alkyl having 8, 10 or 12 carbon atoms and 
n represents the numbers 3, 4 or 5. 
Examples which may be mentioned of N-alkyl-lactams of the formula (I) are: 
N-dodecyl-caprolactam 
N-decyl-caprolactam 
N-octyl-caprolactam 
N-dodecyl-pyrrolidone 
N-decyl-pyrrolidone 
N-octyl-pyrrolidone 
N-dodecyl-valerolactam 
N-decyl-valerolactam 
N-octyl-valerolactam. 
The N-alkyl-lactams of the formula (I) are already known (compare J. Org. 
Chem. 18, 1087 (1953); Ann. Chem. 596, 203 (1955); J. Amer. Chem. Soc. 69, 
715 (1947); DE-AS (German Published Specification) 1,160,268; EP-OS 
(European Published Specification) 0,077,078 and WO 88/00,184). 
The active compounds of the formulae (II) and (III) and their use for 
combating phytopathogenic fungi are likewise known (compare EP-OS 
(European Published Specification) 0,040,345 and German Patent 
Specification 2,324,010). The active compounds can be employed here in the 
customary formulations. They are preferably applied in the form of aqueous 
spray liquors. 
In addition to the active compounds of the formulae (II) and (III), the 
spray liquors which can be used according to the invention can also 
contain one or more other active compounds. Compounds which are preferably 
suitable here are those with fungicidal properties. Examples which may be 
mentioned of such active compounds which can additionally be used are: 
1-(4-chlorophenoxy)-3,3-dimethyl-(1,2,4-triazol-1-yl)butan-2-one 
(triadimefon), 
1-(4-phenyl-phenoxy)-3,3-dimethyl-(1,2,4-triazol-1-yl)butan-2-ol 
(bitertanol), 
N,N-dimethyl-N'-phenyl-(N'-fluorodichloro-methylthio)sulphamide 
(dichlofluanid), 
N,N-dimethyl-(N'-fluorodichloromethylthio)-N'-(4-methylphenyl)-sulphamide 
(tolylfluanid), 
N-trichloromethylmercapto-4-cyclohexene-1,2-dicarboxamide (captan), 
N-(1,1,2,2-tetrachloroethyl-sulphenyl)-cis-4-cyclohexene-1,2-dicarboxamide 
(captafol), 
N-trichloromethylthio-phthalimide (folpet), 
n-dodecyl-guanidine acetate (dodine), 
tetrachloro-isophthalo-dinitrile (chlorothalonil), 
4,5,6,7-tetrachlorophthalide, 
zinc ethylene-bis-dithiocarbamate (zineb), 
manganese ethylene-bis-dithiocarbamate (maneb), 
zinc ethylene-bis-dithiocarbamate/manganese ethylene-bisdithiocarbamate 
(mancozeb), 
zinc propylene-1,2-bis-dithiocarbamate (propineb), 
1-[3-(4-(1,1-dimethylethyl)-phenyl)-2-methylpropyl]-piperidine 
(fenpropidin), 
N-tridecyl-2,6-dimethyl-morpholine (tridemorph), 
2-[2-(2,4-dichlorophenyl)-2-(2-propenyloxy)-ethyl]imidazole (imazalil), 
N-[2-(2,4,6-trichlorophenoxy)-ethyl]-N-propyl-1H-imidazole (prochloraz), 
1,2-dimethyl-cyclopropane-1,2-dicarboxylic acid 3,5-dichlorophenylimide 
(procymidone), 
2-methoxycarbamoyl-benzimidazole (carbendazim), methyl 
1-(butylcarbamoyl)-2-benzimidazole-carbamate (benomyl), 
2,4-dichloro-6-(2'-chlorophenyl-amino)-1,3,4-triazine (anilazine), 
bis-(8-guanidine-O-octyl)-amine triacetate (guazatine), 
1-(4-chlorobenzyl)-1-cyclopentyl-3-phenyl-urea (pencyron). 
Possible additives which can be present in the spray liquors which can be 
used according to the invention are surface-active substances, organic 
diluents, low temperature stabilizers and adhesives. 
Possible surface-active substances here are nonionic and anionic 
emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene 
fatty alcohol ethers, alkylaryl polyglycol ethers, alkylsulphonates, 
alkylsulphates and arylsulphonates. The emulsifiers may be present 
individually or as a mixture. Preferably mentioned are 
polyoxyethylene sorbitan monolaurate having on average 20 oxyethylene units 
per molecule, 
polyoxyethylene sorbitan monopalmitate having on average 20 oxyethylene 
units per molecule, 
polyoxyethylene sorbitan monostearate having on average 20 oxyethylene 
units per molecule, 
sorbitan monolaurate, 
sorbitan monopalmitate, 
sorbitan monostearate, 
polyoxyethylene oleyl ether having on average 10 oxyethylene units per 
molecule, 
polyoxyethylene oleyl ether having on average 20 oxyethylene units per 
molecule, 
bis-[.alpha.-methyl-(4-methyl-benzyl)]-phenyl-polyglycol ether having on 
average 27 oxyethylene units per molecule, 
bis-[.alpha.-methyl-(4-n-dodecyl)]-phenyl-polyglycol ether having on 
average 27 oxyethylene units per molecule, 
bis-(4-methyl-benzyl)-phenyl-polyglycol ether having on average 27 
oxyethylene units per molecule, 
bis-(4-n-dodecyl-benzyl)-phenyl-polyglycol ether having on average 27 
oxyethylene units per molecule, 
tris-[.alpha.-methyl-(4-methyl-benzyl)]-phenyl-polyglycol ether having on 
average 17 oxyethylene units per molecule, nonylphenol-polyglycol ether 
having on average 15 oxyethylene units per molecule, 
nonylphenol-diglycol ether having on average 2 oxyethylene units per 
molecule, 
sodium n-dodecyl sulphonate, 
sodium lauryl sulphate, 
sodium 4-(n-nonyl)phenyl-sulphonate, 
sodium 4-(tetrapropylene)-phenyl-sulphonate, 
ammonium 4-(i-dodecyl)-phenyl-sulphonate, 
calcium 4-(i-dodecyl)-phenyl-sulphonate, 
(2-hydroxyethyl)-ammonium 4-(n-dodecyl)-phenyl-sulphonate, 
bis-(2-hydroxyethyl)-ammonium 4-(n-dodecyl)-phenyl-sulphonate, 
tris-(2-hydroxyethyl)-ammonium 4-(n-dodecyl)-phenyl-sulphonate, 
calcium 4-(n-dodecyl)-phenyl-sulphonate. 
The emulsifiers used in practice from the group of alkylaryl polyglycol 
ethers are in general mixtures of several compounds. These are, in 
particular, mixtures of substances which differ in the degree of 
substitution on the phenyl ring bonded to the oxyethylene unit and the 
number of oxyethylene units. Fractions can therefore also be calculated as 
mean values for the number of substituents on the phenyl ring. Examples 
which may be mentioned are substances for which the following average 
compositions result: 
##STR5## 
Organic diluents which can be present in the spray liquors which can be 
used according to the invention are all the polar and non-polar organic 
solvents which can be customarily employed for such purposes. Preferred 
possible solvents are ketones, such as methyl isobutyl ketone and 
cyclohexanone, and furthermore amides, such as dimethylformamide, and 
moreover cyclic compounds, such as N-methyl-pyrrolidone and butyrolactone, 
and moreover strongly polar solvents, such as dimethyl sulphoxide, and 
furthermore aromatic hydrocarbons, such as xylene, and in addition esters, 
such as propylene glycol monomethyl ether-acetate, dibutyl adipate, hexyl 
acetate, heptyl acetate, tri-n-butyl citrate and di-n-butyl phthalate, and 
furthermore alcohols, such as ethanol, n- and i-propanol, n- and 
i-butanol, n- and i-amyl alcohol, benzyl alcohol and 1-methoxy-2-propanol. 
Low temperature stabilizers which the spray liquors which can be used 
according to the invention can contain are all the substances usually 
suitable for this purpose. Preferred possible substances are urea, 
glycerol and propylene glycol. 
Adhesives which can be employed in the spray liquors which can be used 
according to the invention are all the substances which are usually 
suitable for this purpose. Preferred possible substances are adhesives 
such as carboxymethylcellulose, naturally occurring and synthetic 
pulverulent, granular or latex polymers, such as gum arabic, polyvinyl 
alcohol and polyvinyl acetate, and naturally occurring phospholipids, such 
as cephalins and lecithins, and also synthetic phospholipids. Further 
additives can be mineral and vegetable oils. 
Water is moreover in each case present in the spray liquors which can be 
used according to the invention. 
In the case of the use according to the invention of N-alkyl-lactams of the 
formula (I), one or more of these N-alkyl-lactams can be employed in the 
spray liquors. 
The active compound concentrations in the spray liquors which can be used 
according to the invention can be varied within a certain range. The 
active compound concentrations are in general between 0.0001 and 3 per 
cent by weight, preferably between 0.001 and 2 per cent by weight. 
The ratio of active compound to N-alkyl-lactam of the formula (I) can also 
be varied within a certain range. The weight ratio of active compound from 
group (A) to N-alkyl-lactam of the formula (I) is in general between 1:0.2 
and 1:5, preferably between 1:0.6 and 1:2. 
The amounts of other active compounds or additives in the spray liquors 
which can be used according to the invention can be varied within a 
substantial range. They are of the order of magnitude as is usually the 
case in such aqueous spray liquors. 
The spray liquors which can be used according to the invention are prepared 
by customary methods. In general, a procedure is followed in which a 
concentrate is first prepared by bringing together the required components 
in any desired sequence and mixing them homogeneously at temperatures 
between 15.degree. and 30.degree. C. and if appropriate filtering the 
mixture formed. To prepare the ready-to-use spray liquors, the 
concentrated formulation is mixed with the particular desired amount of 
water, if appropriate with stirring and/or pumping, so that the 
formulation is uniformly distributed in the water as a fine dispersion. 
It is also possible to add the one or more N-alkyl-lactams of the formula 
(I) if the concentrate is diluted with water to give the ready-to-use 
spray liquor. 
It is possible to use, both for the preparation of the concentrated 
formulations and for the preparation and application of the spray liquors 
which can be used according to the invention, all the mixing apparatuses 
and spray apparatuses usually suitable for these purposes. 
By using one or more N-alkyl-lactams of the formula (I) in aqueous spray 
liquors based on active compounds of the formulae (II) and/or (III), 
crystallization of the active compound both in the concentrated 
commercially available formulation and in the filters and discharge 
openings of the spray apparatuses during application of the aqueous spray 
liquors prepared therefrom is either completely suppressed or prevented to 
the extent that application of the spray liquors is not impaired.

The preparation and crystallization properties of the spray liquors which 
can be used according to the invention are illustrated by the following 
examples. 
PREATION EXAMPLES 
EXAMPLE 1 
To prepare a formulation, 12.5 parts by weight of 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
of the formula 
##STR6## 
10.0 parts by weight of N-(n-dodecyl)-caprolactam, 35.0 parts by weight of 
cyclohexanone, 
6.5 parts by weight of the emulsifier of the average composition of the 
formula 
##STR7## 
6.5 parts by weight of (2-hydroxyethyl)-ammonium 
4-(n-dodecyl)-phenylsulphonate and 
29.5 parts by weight of water, 
are mixed at room temperature and stirred to give a homogeneous liquid. A 
spray liquor containing the concentrate in a concentration of 2% by weight 
is prepared from the resulting concentrate by mixing with water. 
EXAMPLE 2 
To prepare a formulation, 12.5 parts by weight of 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
of the formula 
##STR8## 
12.5 parts by weight of N-(n-octyl)-pyrrolidone, 36.0 parts by weight of 
cyclohexanone, 
6.5 parts by weight of the emulsifier of the average composition of the 
formula 
##STR9## 
6.5 parts by weight of (2-hydroxyethyl)-ammonium 
4-(n-dodecyl)-phenylsulphonate and 
27.0 parts of water, 
are mixed at room temperature and stirred to give a homogeneous liquid. A 
spray liquor containing the concentrate in a concentration of 2% by weight 
is prepared from the resulting concentrate by mixing with water. 
EXAMPLE 3 
To prepare a formulation, 
12.5 parts by weight of 
1-(4-chlorophenyl)-4,4-dimethyl3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
of the formula 
##STR10## 
12.5 parts by weight of N-(n-dodecyl)-pyrrolidone, 36.0 parts by weight of 
cyclohexanone, 
6.5 parts by weight of the emulsifier of the average composition of the 
formula 
##STR11## 
6.5 parts by weight of (2-hydroxyethyl)-ammonium 
4-(n-dodecyl)-phenylsulphonate and 
27.0 parts of water, 
are mixed at room temperature and stirred to give a homogeneous liquid. A 
spray liquor containing the concentrate in a concentration of 2% by weight 
is prepared from the resulting concentrate by mixing with water. 
COMISON EXAMPLE A 
To prepare a formulation, 
12.5 parts by weight of 
1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-yl-methyl)-pentan-3-ol 
of the formula 
##STR12## 
6.5 parts by weight of the emulsifier of the average composition of the 
formula 
##STR13## 
6.5 parts by weight of (2-hydroxyethyl)-ammonium 
4-(n-dodecyl)-phenylsulphonate, 
35.0 parts by weight of cyclohexanone and 
39.5 parts by weight of water, 
are mixed at room temperature and stirred to give a homogeneous liquid. A 
spray liquor containing the concentrate in a concentration of 2% by weight 
is prepared from the resulting concentrate by mixing with water. 
Use Example I 
To test the crystallization properties, in each case 250 ml of an aqueous 
spray liquor having a concentrate content of 2% by weight are pumped in 
circulation through a fine-meshed sieve for 15 minutes in a flow-through 
apparatus with the aid of a pump. After this operation has been repeated 
eight times with 250 ml of freshly employed spray liquor each time, the 
crystal deposit on the sieve is photographed. 
The corresponding photographs are shown in FIGS. 1 to 4. 
FIG. 1 shows, in 25-fold magnification, the crystal deposit formed on the 
sieve on pumping through eight 250 ml batches of the spray liquor 
according to Example (A). 
FIG. 2 shows, in 25-fold magnification, the crystal deposit formed on the 
sieve on pumping through eight 250 ml batches of the spray liquor 
according to Example (1). 
FIG. 3 shows, in 25-fold magnification, the crystal deposit formed on the 
sieve on pumping through eight 250 ml batches of the spray liquor 
according to Example (2). 
FIG. 4 shows, in 25-fold magnification, the crystal deposit formed on the 
sieve on pumping through eight 250 ml batches of the spray liquor 
according to Example (3). 
The figures show that the sieve is partly blocked in the case of the known 
spray liquor according to Example (A) , whereas in the case of the spray 
liquors according to Examples (1) to (3), no crystal deposit is observed. 
It is understood that the specification and examples are illustrative but 
not limitative of the present invention and that other embodiments within 
the spirit and scope of the invention will suggest themselves to those 
skilled in the art.