JPH01249133A - Liquid suspension of chitin having uniform quality - Google Patents

Abstract

PURPOSE:To obtain a suspension of chitin in an org. liquid having a uniform quality by giving a high velocity to a suspension of powdery chitin in an org. liquid by passing the suspension through an orifice, then reducing the velocity rapidly, and repeating the process. CONSTITUTION:A liquid suspension of powdery chitin is prepd. by dispersing the powdery chitin in an org. liquid such as a high boiling point alcohol, etc. A high velocity is given to the liquid suspension by passing the liquid suspension through an orifice having a small diameter generating at least 200kg/cm<2> pressure drop, then a shearing force is exerted to the liquid suspension by reducing the velocity rapidly by allowing the suspension to cause collision. The processes are repeated, and a stable liquid suspension of chitin in an org. liquid having >=200% holding capacity for org. liquid, >=100poise viscosity at 3wt.% solid matter concentration, and >=50 stable amt. after standing a suspension of 0.5wt.% concn. for 1hr. is obtd. The obtd. liquid suspension of chitin has high holding capacity for org. liquid and high stability of suspension in an org. liquid, and high viscosity in addition to scarce change of viscosity against lapse of time. Accordingly, it is useful as a material for cosmetics.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a homogenized organic liquid suspension of chitin useful as a raw material for cosmetics and a method for producing the same.

(Prior art and problems to be solved by the invention) Chitin exists in large amounts in nature, and like cellulose, it is attracting attention as a renewable resource.In other words, chitin is found in the shells of shrimp, krill, crabs, etc. Chitin is present as a structural polysaccharide in the cell walls of insects, captomillas, and fungi, and is produced widely and in large amounts in nature. Chitin is used as an additive for paper and fibers, and as an additive for photographic products. , pharmaceuticals, cosmetics, and antitumor agents have been proposed, but in order to do so, it is necessary to formulate them in a form that can be used effectively.

Recently, it has been suggested that purified chitin has no adverse effects on the human body and is biocompatible, and its application to medicines, cosmetics, etc. has been proposed. However, purified chitin is a powdery substance that is insoluble in most solvents, and even if it is directly incorporated into cosmetics, etc., it has a rough texture and cannot be used.

Moreover, most of the solvents that can dissolve chitin are special ones, and it is not preferable for these solvents to be mixed into medicines and cosmetics.

There is a possibility of using chitin in the form of fine particles or suspension, which is an easy-to-use form. There are several proposals for making fine particles or suspensions, but the manufacturing methods are complicated, the action of the chemicals is too strong and causes molecular collapse, and the stability of the suspension is poor and it cannot be completed in a short period of time. Most of them have the disadvantage of solid-liquid separation, and none have been put into practical use yet.

On the other hand, the present inventors discovered a method of making chitin and chitosan into a fine particle suspension using water as a medium, and published JP-A-61-14
It was disclosed in Japanese Patent Application Laid-open No. 9237 and Japanese Patent Application Laid-open No. 159430/1983. The fine particle suspension provided by this method has excellent suspension stability and can be used in many applications including cosmetics.

However, this fine particle suspension using water as a medium has the disadvantage that it is difficult to apply it to oil-based cosmetics, ointments, etc. Further, a fine particle suspension using water as a medium forms a film of chitin or chitosan when the water evaporates. The film formed on the skin does not impede skin breathing and is suitable for purposes such as artificial skin and backing agents, but it is not suitable for use in soft cosmetics because it gives a stiff feeling.

(Means for Solving the Problems) As a result of intensive research to solve the above problems, the present inventors found that
Using a specific range of organic liquid as a medium instead of water,
When processed according to the method disclosed in Publication No. 430,
The present invention was achieved by discovering that a finely dispersed suspension of homogenized chitin in an organic solvent can be obtained.

That is, in the present invention, the organic liquid retention value is 200% or more,
Homogenization in an organic liquid characterized by having a viscosity of 100 poise or more at a solid content concentration of 3% by weight, and a stable amount of 50 poise or more after a suspension with a concentration of 0.5% by weight is left for 1 hour. The purpose of this invention is to provide a chitin suspension obtained by

The present invention also provides for passing a suspension of powdered chitin through a small diameter orifice to give the suspension at least 200%
A step of applying a high velocity with a pressure difference of "kg/cm" and then causing a shearing action by colliding and rapidly decelerating the speed, and repeating the above steps until the organic liquid suspension of chitin is substantially The present invention also provides a method for producing a homogenized chitin suspension, comprising the steps of:

In the present invention, the stable amount, organic liquid retention value, and viscosity of the chitin suspension are values measured by the method shown below.

(1) Stable amount; dilute an organic liquid gel suspension of chitin with an organic liquid to
．． A 5% by weight dispersion is prepared.

Put this in a 100 @Z graduated cylinder and add 1 at room temperature.
The stable amount is a value defined as 100-A, where A- is the amount of clear supernatant liquid produced after standing for a period of time.

(2) Organic liquid retention value: A chitin organic liquid suspension sample is placed in a 200 mesh wire mesh basket, and the sample is treated with a centrifugal force of 1300 centrifugal force for 20 minutes to remove liquid. Thereafter, the sample is taken out and its weight (fig) is measured.

Next, this sample is washed with about 500 times the sample amount of water, filtered to remove organic liquid, dried at 105° C. until it reaches a constant weight, and its weight (Wzg) is measured.

The organic liquid retention value (W, R, V, ) is calculated by the following formula.

(3) Viscosity; The temperature of an organic liquid suspension sample with a solid content concentration of 3% by weight was adjusted to 25°C, and the viscosity was measured using a B-type viscometer (manufactured by Tokyo Keiki), model BH, with a rotor Nα of 7.20 rotations. Measure.

The organic liquid used in the present invention is preferably a high-boiling alcohol, particularly an alcohol with a boiling point of 150°C or higher. Specifically, it is selected from monohydric alcohols such as α-terpineol, dihydric alcohols such as propylene glycol and 1,3-butylene glycol, and trihydric alcohols such as glycerin.

Apparatus suitable for carrying out the production method of the present invention is a high-pressure homogenization apparatus for producing emulsions and dispersions, which is widely used in dairy products manufacturers and the like.

Homogenizers of this type and their operating mechanisms are well known, e.g.
Mical Engineering), 13(5)
+86-92 (1974).

In carrying out the present invention, purified chitin is once dried and then ground into small pieces with a longest part of about 1 to 2 mm, which is used as a raw material. This is dispersed in an organic liquid to form a suspension, and the amount of chitin dispersed is preferably at most 10% by weight, more preferably in the range of about 1 to 5%.

This suspension was introduced into the homogenizer for at least 20 min.
0 kg/cm”, preferably 350-560 kg/c
m'' pressure is applied.Then, this suspension is passed through a homogenizer many times, and the organic liquid retention value is 200% or more, the viscosity at 3% solids concentration is 100 poise or more, and 0. . Obtain a stable organic liquid suspension of chitin whose stable amount is 50 or more after leaving the suspension at a concentration of 5% by weight for 1 hour. Organic liquid retention value and viscosity of the organic liquid suspension of chitin. If the stable amount is outside the above range, the organic liquid and chitin will separate and a stable paste state will not be maintained and the form will not be industrially usable. It is believed that the interplay of pressure drop and temperature increase during passage through the homogenizer is necessary to produce a stable chitin suspension according to the invention.

The organic liquid suspension of chitin obtained by the present invention has a high degree of organic liquid retention and suspension stability in the organic liquid,
It exhibits very high viscosity and shows little change in viscosity over time.

Conventional chitin cannot be reduced to a particle size of 200μ〇 even when frozen and crushed, but the chitin fiber diameter in the suspension of the present invention is 20~0.0μ〇.
It has been crushed to 1μ, which is 1710 to 1/1μ compared to frozen crushing.
It is detailed to 1000.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 30 g of commercially available chitin powder (Sakura Chikkarin ■) was dispersed in 970 g of glycerin to prepare a 3% by weight chitin suspension. This was mixed with a Gaulin homogenizer (15?l-8
TA ) at room temperature (approximately 25°C), 420kg/
The suspension was passed through the suspension 40 times at a pressure of 100 cm. As the number of passes increased, the suspension became more viscous and gel-like.

At the end of 40 passes, the liquid temperature reached 75°C, and a stable gel-like chitin suspension was obtained. When the physical properties of this suspension were measured, the following values were obtained.

(1) Stable amount: io.

(2) Liquid retention value 7 3.190% (3) Viscosity
Degree: L481 poise Example 2 30 g of commercially available chitin powder (Sakura Chikkarin ■) was dispersed in 970 g of propylene glycol to prepare a 3% by weight chitin suspension. This was mixed with a Gaulin homogenizer (1
5M-8T8) at room temperature (about 25°C), 420
The suspension was passed 40 times at a pressure of "kg/ca+". As the number of passes increased, the suspension became more viscous and gel-like.

At the end of 40 passes, the liquid temperature reached 75°C, and a stable gel-like chitin suspension was obtained. When the physical properties of this suspension were measured, the following values were obtained.

(1) Stable IL: 100 (2) Liquid retention value 72.226% (3) Viscosity: 8
80 poise Example 3 30g of commercially available chitin powder (Sakura Chikkarin■) was 1.3
- Dispersed in 970 g of butylene glycol, 3% by weight
A chitin suspension was prepared. This was charged into a Gaulin homogenizer (15M-87A) at room temperature (approximately 25°C) and passed through it 40 times at a pressure of 420 kg/cm''.

As the number of passes increases, the suspension becomes more viscous and gel-like.

At the end of 40 passes, the liquid temperature reached 75°C, and a stable gel-like chitin suspension was obtained. When the physical properties of this suspension were measured, the following values were obtained.

(1) Stable amount; 100 (2) Liquid retention value: 2,327% (3) Viscosity
Degree: 654 poise [Effect of the invention] Some cosmetics and external medicines are based on liquid paraffin, petrolatum, beeswax, lanolin, etc., and the organic liquid suspension of chitin of the present invention mixes well with them. It can be mixed with colorants, vitamins, hormones, fragrances, antioxidants, surfactants, ultraviolet inhibitors, water, etc. to make cream, paste, and liquid products.

In this case, the physical properties of the suspension of the present invention, such as non-irritation, odorlessness, non-volatility, moisture retention, viscosity, and skin affinity, can be advantageously utilized.

Claims (1)

[Scope of Claims] 1. An organic liquid retention value of 200% or more, a viscosity of 100 poise or more at a 3% solid content concentration, and a 0.5% by weight suspension after being left for 1 hour. A chitin suspension homogenized in an organic liquid, characterized in that the stable amount is 50 or more. 2. The chitin suspension according to claim 1, wherein the organic liquid is a high boiling point alcohol. 3. Passing an organic liquid suspension of powdered chitin through a small diameter orifice to give the suspension at least 200 kg/cm
A step in which a high velocity is applied with a pressure difference of ^2, and then a shearing action is performed by colliding and rapidly decelerating;
repeating the above steps until the suspension of chitin in an organic liquid becomes a substantially stable suspension.