JPS5824525A - Production of hard solidifying substance - Google Patents

Abstract

PURPOSE:A hard solidifying substance such as oily pyrethroid, phthalthrin, is crystallized by use of a solvent that is mutually compatible with the oily substance, when necessary, crushed and dried to produce the crystals of the hard solidifying substance readily in a short time in an industrial scale. CONSTITUTION:A hard solidifying liquid substance such as resmethrin and at least one of organic solvents which are compatible with the liquid substance such as dichloromethane or dibutyl phthalate are mixed and cooled to effect crystallization, when necessary, the solid is crushed and dried to give the crystals of the hard solidifying substance. The amount of the solvent is 3-50wt% based on the substance and the substance is dissolved at room temperature or under heating, then they are cooled without separating the solvent. The amount of the solvent and the crystallization temperature are varied to control the crystallization time appropriately. Further, flakes also are made readily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a koji-hardening substance having a melting point above normal temperature, and more particularly to a method for producing a koji-hardening substance, such as a dehiscible pyrethroid, a hard-to-hardenable P-alkylamino. This is a method of easily solidifying diphenyl atones using an organic solvent to obtain a solid substance.

In the present invention, phthalthrin and resmethrin are representative examples of dehiscence-promoting pyrethroids.For example, phthalthrin and resmethrin have melting points of 60 to 80, respectively.
℃ and 40 to 55℃, but they are obtained as oily liquids by normal production methods, and are themselves very dehiscence-prone. , it takes about one week.

However, on the other hand, if these industrially produced pyres tetraids are put into containers in their oily state and made into products, there is a possibility that they will assimilate and crystallize in the packaging containers during transportation or storage. Once crystallized in a packaging container, frequent operations such as heating and melting or crushing are required to remove the crystals, so it is virtually impossible to put the oil in a container and make it into a product. Ta. For this reason, the following operations were usually performed prior to packaging.

That is, first, these pyrethroids obtained in the form of an oil are partially planarized into a slurry over several hours, then transferred to a container and solidified, and the brick or block-shaped crystals thus obtained are further processed. After cooling and making it a perfect crystal,
It was being crushed. This is illustrated as follows.

(Summary of conventional manufacturing methods for powdered pyrethroids) As described above, until now, very complicated operations have been required prior to packaging, and therefore a lot of time, labor, and equipment have been required.

This is because these difficult-to-crystal pyrethroids are flakes.
This is because it is extremely difficult industrially to make it into flakes or to crystallize it as fine particles by spraying.

Against this background, the inventors of the present invention have conducted intensive studies to develop an easier operation method for obtaining crystals of these difficult-to-crystallize pyrethroids. The present inventors have discovered a method that is advantageous when implemented on a large scale, and have completed the present invention by adding various studies to this method.

That is, the present invention uses an organic solvent such as acetone, dichloromethane, dibutyl phthalate, chloroform, methanol, etc., or a mixed solvent thereof, which is mutually soluble in an oily liquid of an exfoliating pyrethroid such as phthalthrin and resmethrin, or a mixed solvent thereof by weight. 2 to 50 inches, preferably 6
After adding ~20 pieces and making it uniform, add 0.1 to 5 pieces of seed crystals by weight if necessary, cool to 40°C or lower, preferably 20°C or lower, and solidify the crystals without separating from the organic solvent. The pyrethroid is then obtained in a crystalline form by removing the grinding solvent. Further, the crystals thus obtained can be obtained as crystalline birethride, which is more preferable in terms of quality and handling.

The above operating steps are illustrated below.

(Summary of the method for producing crystalline pyrethroids of the present invention) The feature of the present invention is that the crystals are solidified using a solidifying substance, such as a solvent that is mutually soluble with the above-mentioned oily pyrethroids. If it is out of this range, the purpose cannot be achieved even if, for example, silicone oil or a large amount of acetone, for example, 50 tons or more, is used. Another feature is that by changing the amount of solvent used and the crystallization temperature, the crystal assimilation time can be freely controlled.
It is in.

The present invention makes it possible to easily obtain crystalline pyrethroids in a short time, which conventionally required a long time, and it is also extremely easy to make them into flakes using a flaker.
It can be easily crushed and dried, and has extremely high industrial value.

The present invention will be explained in more detail with reference to Examples below, but it goes without saying that the present invention is not limited thereto.

Example 1 To 30 t of oily phthalthrin (Neopinamine (registered trademark of Sumitomo Chemical); hereinafter referred to as Neopinamine ■), 3 t of acetone and 0.3 t of seed crystals were added and mixed, and then cooled to 10° C. and allowed to stand. The whole crystal solidifies in about 2 minutes. The mixture was then crushed and dried to obtain a powdered crystalline Neovinaken 30F.

Example 2 Oily neovina 30 FIζ Acetone 4.5- was added and dissolved uniformly, then poured into a 7/I/i vat and 0t
When the mixture was left to cool and stand still, it solidified into crystals in about 5 minutes. Thereafter, it was peeled off and dried to obtain neopinamine 30F in flake form.

Example 3 Oily resmethrin (Kryslon (trademark of Sumitomo Chemical);
From now on, it will be referred to as Cryslon ■. ) Dichloromethane 3 to 30F
After adding F and 0.6 F of seed crystals and mixing, the mixture was cooled to 10° C. and allowed to stand still. The whole crystal solidifies in about 5 minutes. Then, when it is crushed and dried, the powdered crystalline cryslon becomes 30.5 ?
Obtained.

Example 4 30 f of oily p-(1,a-dimethylbutylamino)diphenylamine with methano/L/1.5 F and 0.
Add 5t, mix, and cool to 10°C, and the whole will crystallize in about 8 minutes. Then, it is crushed, dried, and dried to form a powdery P.
-(1e 3-dimethylbutylamino)diphenylamine 30F was obtained.

Reference example: Oily Neovinaden ■30F with silicone (Toshi Silicone 5H-100) 4.5? Add and mix 0.3 t of seed crystals. The whole solution became cloudy and it took 18 hours for the crystals to solidify even after cooling to 10°C.

Claims (1)

[Scope of Claims] (A mixture of the 17ml-forming substance, the wavy liquid, and one or more organic solvents that are mutually soluble is cooled, crystallized, and optionally pulverized. (2) Adding to the oily liquid of the decomposition substance one type or a mixed solvent of two or more organic solvents that are mutually soluble with the oily liquid. The method according to claim 1, wherein 3 to 50% (by weight) of the oil is added to the oily liquid, dissolved at room temperature or under heating, and then cooled, without separating it from the organic solvent. 3) - The method according to claim 1 or 2, which is carried out by adding seed crystals when crystallizing the solidifying substance. (4) As the solidifying substance, a solidifying Piresp I" A method according to claim 1, 2 or 3 using the following.