JPS6323229B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a fire extinguishing foam composition,
More specifically, the present invention relates to a fire extinguishing foam composition comprising a protein hydrolyzate. [Prior Art] Conventional protein hydrolysis products have a high foaming power, and therefore their usefulness as main components of fire extinguishing foams, for example, has been recognized. In order to increase the foaming properties of protein hydrolysis products, for example, there is a method of decomposing scleroprotein into proteose with alkali (Japanese Patent Publication No. 31-6700), and proteose is obtained by decomposing scleroprotein with alkali in two steps. method (Special Publication No. 31-8447), method of alkaline decomposition of animal blood to obtain peptone, and addition of water-soluble metal salts to this (Special Publication No. 32-5150), hydrolysis of hard proteins using slaked lime and caustic soda. Method using a mixture
No. 7896), hydrolysis of hard proteins with alkali
In methods such as the method conducted at 110 to 120℃ (Special Publication No. 33-1941), a protein hydrolyzate with high foaming power is obtained by changing the protein hydrolysis conditions; A method of adding Bacillus natto (Special Publication No. 31-3996), a method of adding ethanolamine or saponin to a protein hydrolyzate (Special Publication No. 7450-1977), and a method of adding an initial condensate of urea to a protein hydrolysis intermediate. Method of adding
-887), a method of treating protein hydrolyzate with ammonium carbonate (Japanese Patent Publication No. 8600, 1973), a method of reacting ferrous salt with a hydrolyzate of keratin protein (Japanese Patent Publication No. 11879, 1977), etc. discloses a technique in which protein hydrolyzate is treated with other substances to enhance its foaming properties. On the other hand, foaming agent compositions containing a surfactant containing a perfluorocarbon group (Japanese Patent Publication No. 47-21078) and a surfactant made from a tetrafluoroethylene oligomer are used as the main component of a protein hydrolysis product. (Japanese Patent Publication No. 47-26160) is known as a foaming composition with high foaming properties. In addition, the special public
-20081 describes that water-soluble compounds containing fluoroalkyl groups improve the foam stability of protein hydrolysates, and Japanese Patent Publication No. 48-23161 describes water-soluble fluorinated aliphatic surfactants and non-fluorine-containing surfactants. It has been disclosed that a combination of hydrocarbon surfactants improves the foam stability of protein hydrolysates. However, these known patent documents disclose that the protein hydrolyzate can be improved by changing the protein hydrolysis conditions or by adding a second component to the protein hydrolyzate to increase its foaming properties and foam stability. The aim was to improve the foaming properties of In contrast, the present inventors have conducted research on the foaming properties of protein hydrolysates from a different perspective than these conventional techniques. That is, the present inventor discovered that the hydrolysis products obtained when animal and plant proteins are hydrolyzed with alkali range from a large molecular weight of about 2 million to a low molecular weight of 5000 or less. Decomposition products have been fractionated according to molecular weight, and the surfactant ability of each fraction has been investigated to study their usefulness as extinguishing agent components. [Problems to be Solved by the Invention] However, the above-mentioned conventional techniques do not consider the essence of the obtained protein hydrolyzate itself, and do not involve processing or adding second components to the protein hydrolyzate. The aim was to improve the foaming properties by adding . Therefore, there are limits to the ability to enhance the inherent foaming properties of protein hydrolysis products, and in order to obtain even better fire extinguishing foams, it is necessary to use expensive processing and expensive additives. Therefore, there is a strong need for an inexpensive fire extinguishing foam with excellent performance. [Means/effects for solving the problems] The present inventor has conducted many studies on protein hydrolysates in order to solve the above-mentioned problems, and the results show that protein hydrolysates are hard proteins. As a result of fractionating keratin hydrolyzate into products with various molecular weights using an ultrafiltration membrane and examining the fire extinguishing ability of the fractionated components, it was found that protein hydrolyzates with a molecular weight cut-off of 300,000 to 1,000 foamed. The present invention was completed based on the discovery that it is extremely useful as a main component of fire extinguishers. That is, according to the present invention, animal and plant proteins are hydrolyzed under normal hydrolysis conditions, the resulting product is subjected to ultrafiltration, and a fractionated product having a molecular weight cutoff of 300,000 to 1,000 is added to a fire extinguishing foam. Use as main ingredient. The thus obtained fractionated product having a molecular weight cut-off of 300,000 to 1,000 has excellent foam firefighting action and is extremely useful as the main component of firefighting foam. As the raw material for the protein hydrolyzate used in the present invention, any protein source of animal or plant origin can be used, such as powders of hooves, horns, blood, etc. of cows and horses, microbial proteins, seed powders, and the like. Protein hydrolysis is carried out under conventional conditions, such as by heating in water at a temperature of about 100 DEG C. for about 1 hour or more using sodium hydroxide or calcium hydroxide at a concentration of 5 to 10% by weight. After the hydrolysis is completed, it is neutralized with an inorganic acid such as hydrochloric acid or sulfuric acid, or an organic acid such as acetic acid, and fine precipitates etc. coexisting are removed using ordinary paper. The protein hydrolyzate thus obtained is concentrated by ultrafiltration using a membrane with a molecular weight cutoff of 300,000, and the concentrated solution is washed with distilled water to completely remove the protein hydrolyzate with a molecular weight cutoff of 300,000 or less. to be collected. The liquid can be further concentrated by reverse osmosis, heating or freeze drying, but the molecular weight of approximately
Reverse osmosis, which can remove up to 1000 components, such as lower peptides and amino acids, is preferred. The residue with a molecular weight cut-off of 300,000 or more remaining on the membrane can be hydrolyzed again to make it into a lower molecular weight one. The molecular weight fraction obtained in this way is 300,000~
The protein hydrolyzate of 1000 has excellent foaming properties and foam stability, and does not contain components that cause aging of fire extinguishers, making it extremely useful as the main component of fire extinguishing agents. The protein hydrolyzate with a molecular weight cut-off of 300,000 to 1,000 according to the present invention can be used as an aqueous solution of 0.5 to 2.0% by weight, and is resistant to hard water, so it exhibits excellent foam fire extinguishing power even in the presence of seawater. . It goes without saying that, for example, a protein hydrolyzate with a molecular weight cut-off of 100,000 to 1,000 or 50,000 to 1,000 also has foam fire extinguishing power. Further, as a foam stabilizer, compounds that provide metal ions, such as water-soluble salts such as calcium, iron (2), and subsalts, such as ferrous sulfate as a typical example, can be added. Other antifreeze agents,
For example, glycols such as ethylene glycol and propylene glycol, viscosity reducing agents such as urea, preservatives such as water-soluble salts of trichlorophenol, foam flow agents such as saponin, etc. can be added. In particular, fluorine-containing surfactants have the effect of significantly improving the fire extinguishing action of the protein hydrolyzate of the present invention. The present invention will be explained in more detail with reference to the following examples. Example: Put 100 g of mixed powder of cow and horse hoof that passed through a Tyler sieve with a mesh size of about 1 mm into a 2-necked three-necked flask with a reflux condenser, add 400 c.c. of distilled water, and add 20 g of sodium hydroxide. Boiled for 90 minutes at ℃. The hydrolyzate obtained in this way was
Using a 300,000 membrane (manufactured by Amicon) and an ultrafiltration device (UHP-150, manufactured by Toyo Shi Co., Ltd.), those with a molecular weight cut-off of 300,000 or more are collected on the membrane.
300,000 or less were recovered in the liquid (yield approximately 70~
80%). The obtained liquid was passed through a reverse osmosis device (RO-3 type, manufactured by Albak Service Co., Ltd.) using a reverse osmosis membrane with a sucrose rejection rate of 15% (manufactured by Albak Service Co., Ltd.).
Products with a molecular weight cut-off of 1000 or less were removed and concentrated to a solid content of 20 to 30% by weight. The material obtained in this way exhibits high foaming power, the stability of the foam produced is extremely excellent, and metal ions, such as calcium ions, iron () ions, zinc ions, manganese ions, magnesium ions, cobalt ions, Nickel ions, etc. do not cause precipitation and increase the stability of the foam. In addition, those having a molecular weight cut off of 300,000 or more can be recovered and used in the next hydrolysis step. The foaming properties of the protein (keratin) hydrolyzate obtained as described above were measured using the apparatus shown in FIG. That is, 30 ml of the sample was placed in an acrylic graduated cylinder 4 containing a perforated disk 7 with a diameter of 30 mm (having four holes with a diameter of 8 mm). The perforated disc 7 is a continuous hammering rod 5 that penetrates the rod case 3.
The repeating rod 5 is connected to the metal disc 1 via the crank rod 2. When the metal disk 1 rotates in the direction of the arrow, the repeatedly striking rod 5 moves up and down repeatedly, and the sample moves up and down the hole in the perforated disk 7, producing bubbles. In this experiment, the perforated disk was
The bubble height was measured after 5 seconds and 30 minutes. The graduated cylinder is 25 mm with water jacket 6.
It was kept at ℃. Foam stability was evaluated by measuring the foam height after 30 minutes and the time for 25% (7.5 ml) and 50% (15 ml) of the sample to separate from the foam (25% and 50% drain time). The results of the experiment are shown in Table 1.

[Table] *Protein hydrolyzate solution before ultrafiltration.
In addition, ferrous sulfate (0.5 to 0.5 to
2.0% by weight), and in addition to the above foam stabilizer, N,M,N-trimethyl,N-3-(perfluorooctylsulfonylamino)propylammonium anion which is a typical fluorosurfactant. Dido [C ₈ F ₁₇ SO ₂ NH (CH ₂ ) ₃ N ⁺
(CH ₃ ) ₃ I ^- ] was added in an amount of 1.0% by weight (based on the protein hydrolysis concentrate), and an extinguishing test was conducted as follows. Pour 50 g of gasoline or methanol as fuel into a square iron combustion dish (burning area: 0.5 cm ² ), 70.7 cm on each side and 40 cm in height, ignite it, and after 5 minutes after ignition, add a 6% aqueous solution of the sample to a fixed type. Foam was discharged from the foam discharge nozzle onto the combustion surface along the wall of the combustion dish. The results of the fire extinguishing test are shown in Table 2.

【table】

〔Effect of the invention〕

The protein hydrolyzate with a molecular weight cut-off of 300,000 to 1,000 according to the present invention has excellent foaming properties and foam stability, and also has high foam extinguishing properties, and has extremely excellent foam extinguishing properties when used as a foam fire extinguishing agent. It exhibits fire extinguishing properties and is resistant to hard water, making it effective in extinguishing fires at sea. Further, if used in combination with a fluorine-based surfactant or the like, even higher fire extinguishing properties can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an experimental apparatus for measuring foaming properties. Codes in the diagram: 1...Metal disc, 2...Crank rod, 3...Rod case, 4...Measuring cylinder, 5...Repeating rod, 6...Water jacket,
7... Perforated disc.

Claims (1)

[Claims] 1. A fire extinguishing foam composition characterized by containing a protein hydrolyzate having a molecular weight cut-off of 300,000 to 1,000 and, if necessary, a foam stabilizer and other additives.