JPS5984765A - Method of preventing consolidation of powdered body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a method for preventing caking of deliquescent substances such as common salt or ammonium chloride under packaging.

Generally, when a deliquescent substance becomes a powder, it absorbs and releases moisture between the powder and the outside atmosphere, so this t5) body undergoes repeated deliquescence and recrystallization, resulting in a lumpy state (which solidifies). ) and lose its properties as a powder. Therefore, in order to prevent these substances from solidifying under packaged conditions, conventionally the moisture absorbent was packed in bags (mainly cloth bags).
The powder was directly mixed into the packaged powder, or an anti-caking agent such as sodium phosphate was mixed into the powder. However, in the former case, if the bag is torn, the moisture absorbent inside will mix with the powder, and since both are often of similar colors, it is almost impossible to separate them once they are mixed. In addition, depending on the degree of mixing, direct mixing does not maintain the purity of the powder, so there is a problem in that the commercial value of the powder decreases significantly. .

This invention was made to solve the above-mentioned problems, and its purpose is to package deliquescent powder such as salt or ammonium chloride in a film with normal moisture permeability. The outside is sealed with a film with extremely low moisture permeability that does not actively allow water vapor to pass through, and a bag of moisture absorbent is placed between the two films, so that the moisture absorbent is directly applied to the powder. It is an object of the present invention to provide a method for preventing caking of powder, which can easily and reliably prevent caking for a long period of time with high purity without touching the powder and without mixing an anti-caking agent.

The present invention will be explained below based on the drawings.

For example, a deliquescent powder 1 such as table salt has a moisture permeability of 5 to 1000 g/m, which is a range that allows water vapor to pass through to some extent.
Film 2 made of polyethylene material with 2/24hr
This is further wrapped with a film 3 made of a transparent or translucent polyethylene material having a moisture permeability of 0.5 to 100 g/m2/24 hr, which does not actively allow water vapor to pass through, and both of these films are After storing a moisture absorbent 4 made of calcium chloride or the like in a bag in the internal space between 2 and 3, the storage opening 5 of the outer film 3 is sealed by heat welding or the like.

As described above, even if the powder l releases the moisture contained in the film 2 due to the inherent property of deliquescent common salt, this film 2
For example, as mentioned above, since it has a moisture permeability of 5 to 1000 g/m2/24 hr, it allows the above-mentioned water to emanate from the film surface, but the outside of the film 2
0.5 to 100 g/m2/ that actively prevents water vapor from passing through
It is enclosed in a sealed manner by a film 3 having a permeability of 24 hours. Therefore, the moisture emanating from the body 1 is absorbed by the moisture absorbent 4 present between the films 2 and 3. As a result, the powder l can maintain its normal powder form for a long period of time.

Also, since the outside of the film 2 that wrapped the body 1 was wrapped with a transparent or semi-transparent film 3, and the moisture absorbent 4 was placed in a bag, the moisture absorbent 4 could be accidentally dropped during unpacking. )
It has the advantage that it is possible to reliably prevent it from entering the body 1, and that its mode can be easily recognized from the outside.

Next, a first embodiment of the present invention will be explained with reference to Table 1.

In this first example, a body (1) containing 20 kg of common salt was wrapped in kraft paper with a moisture permeability of approximately 500 g/m''/24 hr.The outside of the body was wrapped with a moisture permeability of approximately 50 g/rn2.
/ 24 hr, hermetically packaged with a film 3 made of transparent polyethylene material. And this film 2
．． A moisture absorbent 4 containing 50 g of calcium chloride in a cloth bag was housed in the space between 3 and 3. The above sample is referred to as rAJ, and for comparison with that of this invention, the packaging style is the above sample rAJ.
Sample rBJ is exactly the same as sample rBJ, but the moisture absorbent 4 is not placed between films 2 and 3, and the packaging style is exactly the same as sample rBJ described in 2.
5) Body 1 contains phosphoric acid 2- which is an anti-caking agent.
Sample "C" was prepared by directly adding and mixing 80 g of sodium, and these samples were "8".

When rBJ and rcJ were stored in a natural environment, the results shown in Table 1 below were obtained.

Table 1 Category Sample Sample Sample rAJ rBJ rCJ storage period
(kg/c+J) (kg/c+J)
(kg/+Jl) 6 days 0 0.6
015 days 0 1.3 0
30 days 0 1.5 0.260
Days 0 2.3 0.6 Note 1) The numbers (kg/c+J) in the table indicate the strength of pressure required to break up the lumps of common salt.

Note 2) The salt used is the same for all samples, and is high purity salt with thorium chloride purity of 99.9%, and the particle size is O,
1 mm or less, and the average particle size is 0.07 mm.

Further, a second embodiment of the present invention will be explained in Table 2.

In this ff12 example, 15 kg of ammonium chloride powder was used.
The body 1 was wrapped with a film 2 made of polyethylene material with a moisture permeability of 120 g/m"/24 hr. This was further wrapped with a film 2 made of a translucent polyethylene material with a moisture permeability of 12 g/m"/241 hr. 3 and sealed in a sealed package. And the above film. A moisture absorbent 4 containing 40 g of calcium chloride in a bag was housed in between 3 and 3. This sample was designated as rDJ, and in order to compare it with that of this invention,
The packaging style is exactly the same as that of the sample rDJ as described above, and the moisture absorbent 4 is not placed between the films 2 and 3.
In addition, the packaging style is exactly the same as sample rEJ described in 2, and powder 1 of 15 kg of ammonium chloride powder in film 2 contains 10 mg of magnesium chloride, which is an anti-caking agent.
0g was directly added and mixed as sample rFJ,
These samples rl)J.

When rEJ and rFJ were stored in a natural environment, the results shown in Table 2 below were obtained.

Table 2 Category Sample Sample Sample 1rDJ
rlEJ I'FJ storage period (kg/cd) (
Brightness/cJ) (kg/C) 6 days 0
0 0 15 days 0 0 030 days
0 1.4 060 days 0
2.0 0.3 Note 1) Numbers in the table (kg/
cJ) indicates the intensity of pressure required to break up the ammonium chloride lumps.

Note 2) The ammonium chloride used was the same for all samples, the purity of ammonium chloride was 99.0%, the particle size was less than Q, l m m, and the average particle size was 0.05 mm.
It is.

Other examples include potassium chloride.

Powders such as sugar were also packaged using the same method as in the first example, and all powders were packaged in the same manner as in the first example. Almost the same effects as in the second example were obtained.

As explained above, the present invention uses powder such as deliquescent common salt or ammonium chloride with a water vapor permeability of 5 to 1000.
wrapped in a polyethylene film with a moisture permeability of 0.5 to 100 g/m”/24 hr.
/m" /24 hr By sealingly packaging the powder with a polyethylene film and placing a bag of moisture absorbent between the two films, the above-mentioned powder can be absorbed by the properties inherent to, for example, common salt. Even if moisture is released, the moisture is actively absorbed by the moisture absorbent present between the two films, making it possible to easily and reliably prevent the caking of the powder, thus maintaining the normal shape for a long time. In addition, since the moisture absorbent is located between both films and does not come into direct contact with the powder, the powder maintains its high purity, which reduces the commercial value of this type of powder. This has the effect of significantly improving

[Brief explanation of drawings]

The drawing is a sectional view showing a packaging mode of powder according to the caking prevention method of the present invention. ■... Powder 2.3... Film 4.
・・Moisture absorbent

Claims (2)

[Claims] (1) Moisture permeability of powder of deliquescent substance 5 to 1000g
/m”/24hr,
Furthermore, the moisture permeability on the outside is 0.5 to 100 g/m” /
, 24 hours, and a moisture and air absorbent is present in the space between the two films to prevent caking of the powder over the period of time. A method for preventing caking of t5'j bodies, characterized by: (2) Said moisture permeability: 0.5 to 1 O-Og/m2/24
16) A method for preventing caking of koji as set forth in claim 1, characterized in that the film material having ``h'' is transparent or translucent.