JP2003049169A - Powdery flame retardant and method of producing flame- retardant foam by means of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powdery flame retardant that is useful for simply producing foam having excellent flame retardancy and a method of producing flame- retardant foam. SOLUTION: The powdery flame retardant agent includes certain amounts of ammonium chloride, pentaerythritol, dicyandiamide and propylene glycol, but does not include sodium tungstate, ammonium sulfate, formaldehyde, uric acid and ammonium monophosphate. The powdery foaming agent is admixed to a foaming material and the resultant composition is foamed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a powdery flame retardant, a liquid flame retardant and a method for producing a flame retardant foam using these flame retardants.

[0002]

2. Description of the Related Art Conventionally, foamed materials such as urethane have been widely used as cushioning materials for automobile seats, heat insulating materials for construction, etc. as industrial materials. However, a foam such as urethane has a very small flame retardancy, and may burn or drop while burning, which may cause the spread of fire to other materials. Conventionally,
Since it was difficult to make urethane and other foams flame-retardant, for example, in the case of automobile seats, cigarettes are used on sheets where urethane foam is used under a flame-retardant or flame-proof seat cover. Even if the seat cover is flame-retardant, the heat of the cigarettes causes holes to gradually open up until it comes into contact with the urethane foam under the seat cover, which may cause fire or toxic gas. It was often
It is desired to use a flame-retardant foam material also in a heat insulating material for buildings and the like from the viewpoint of suppressing fire damage. At present, there are known self-extinguishing foams in which combustion or flames stop in a short time when they are separated from an open flame. However, the fire easily melts or shrinks the fired part to form a recess. However, it is not satisfactory due to the formation of holes and holes, and a foam having excellent flame retardancy is desired. Further, as a method for imparting flame retardancy, a method of impregnating an article with a liquid of a flame retardant is known, but in this method, it is necessary to perform the formation of the article and the impregnation step separately, It was complicated. Therefore, it is desired that a foam having flame retardancy can be easily prepared.

[0003]

Therefore, the present invention provides a powdery flame retardant useful for easily preparing a foam having excellent flame retardancy, and a method for producing a flame retardant foam using the same. Etc. are intended to be provided.

[0004]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventor has found that the above-mentioned object can be effectively achieved by a powdery flame retardant containing a specific component. The invention has been reached.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. The powdery flame retardant of the present invention comprises ammonium chloride, pentaerythritol, dicyandiamide and propylene glycol as the flame retardant component. Ammonium chloride is a white crystal at room temperature and has a property of being well soluble in water. Pentaerythritol is a colorless crystal at room temperature and is soluble in water. Dicyandiamide is a colorless crystal at room temperature and is soluble in water. Propylene glycol is
It is a colorless viscous liquid at room temperature. The powdery flame retardant of the present invention is 20 to 40 parts by mass, preferably 25 to 30 parts by mass of pentaerythritol with respect to 100 parts by mass of ammonium chloride.
Parts by weight, dicyandiamide 20-40 parts by weight, preferably 25-30 parts by weight and propylene glycol 0.2-.
It is composed of 0.6 parts by mass, preferably 0.3 to 0.5 parts by mass, and does not contain sodium tungstate, ammonium sulfate, formaldehyde urea and ammonium monophosphate. The powdery flame retardant of the present invention has a slightly yellowish coloration. By the way, propylene glycol is a viscous liquid, and even if it is mixed, powdery flame retardant can be produced because the amount of propylene glycol added is small, so that it is supported by crystals of other flame retardant components. It is presumed that the powder adheres in such a form that the powder state is maintained. The powdery flame retardant of the present invention provides reliable flame retardancy within the range of each flame retardant component. The powdery flame retardant of the present invention is composed of only four kinds of components that are industrially well used and commercially available, and can be prepared by simply mixing these components, so that the manufacturing cost can be suppressed.

The powdery flame retardant of the present invention is dissolved in water to form an aqueous solution, the water content of the aqueous solution is evaporated to obtain a precipitate, which is dried to obtain four kinds of flame retardant of the present invention. It is also possible to obtain a solid flame retardant in which the components are uniformly mixed. 0.1 to 40% by mass of powdered flame retardant in water, preferably,
It is suitable to dissolve it to a concentration of 5 to 30% by mass, but it is not particularly limited. Also, evaporation or drying is
A solid flame retardant can be quickly obtained by performing heating at a temperature of 0 ° C. or lower with a water bath or a distillation device while heating lightly.
It should be noted that the flame retardancy may be deteriorated by heating for over 70 ° C for a long time. The solid flame retardant thus obtained is finely pulverized into powder by using a mortar or a mill mixer. The particle size of the powder is not particularly limited as long as the powdered solid flame retardant is mixed with the foam material to obtain a foam having flame retardancy, but for example, 1 to 50 μm, particularly preferably 5 to 10 μm is suitable. Is.

The liquid flame retardant of the present invention has an ammonium chloride content of 1.0 to 30.0% by mass, preferably 2.0 to 23.0.
% By mass, pentaerythritol 0.5 to 10.0% by mass, preferably 0.6 to 7.0% by mass, dicyandiamide 0.5 to 10.0% by mass, preferably 0.6 to 7.0% by mass.
Mass%, propylene glycol 0.01-0.2 mass%
Preferably 0.01-0.1 wt% and water 49.8-9
It is composed of 7.99% by mass, preferably 62.9 to 96.79% by mass, and does not contain sodium tungstate, ammonium sulfate, formaldehyde urea and ammonium monophosphate. Although the four kinds of components of the liquid flame retardant may be directly dissolved in water, a more effective aqueous solution of the flame retardant can be obtained by the following procedure. First, ammonium chloride and pentaerythritol are dissolved in water to prepare an aqueous solution. On the other hand, dicyandiamide is dissolved in water to prepare an aqueous solution. When preparing these aqueous solutions, the temperature of water is
For example, 30 to 70 ° C, preferably 36 to 65 ° C is suitable. If it exceeds 70 ° C, the flame retardancy may be deteriorated, so it should be avoided. After thoroughly mixing the two prepared aqueous solutions, propylene glycol is added to this mixed solution and dissolved by stirring. In addition, when mixing, you do not need special equipment etc., the aqueous solution in the container,
The liquid flame retardant is very easy to prepare, since it is only necessary to stir it with a stirring rod or the like so as to make it uniform. The liquid flame retardant may be used as it is as an undiluted solution, or may be diluted with water 2 to 20 times so as to obtain a desired flame retardancy.

The foam used in the method for producing a flame-retardant foam of the present invention is a polyurethane foam or a plastic foam other than polyurethane, for example, a thermoplastic.
It may be a thermosetting plastic foam or the like, and is not particularly limited. Polyurethane foam is preferable from the viewpoints of material cost, easiness of production and the like. Polyurethane foam is generally a mixture of a main component polyol, a curing agent polyisocyanate, and water, a foaming aid, an additive such as a catalyst,
Causes urethane formation reaction and foaming reaction with heat generation,
When it is desired to foam and give a desired shape, injection molding can be performed using a mold or the like. As a polyol,
Examples thereof include polypropylene glycol, polyethylene glycol, polyethylene adipate, polypropylene adipate, and the like. Examples of polyisocyanates include tolylene diisocyanate, 4,4′-diphenylmethane isocyanate, 1,6-hexamethylene diisocyanate, and isophorone diisocyanate. Polyurethane foam is mainly composed of a polyol having two or more active hydrogen groups (-OH groups) in one molecule and a polyisocyanate having two or more isocyanate groups (-NCO groups) in one molecule. The polyol and the polyisocyanate may be blended so that the ratio of the number of active hydrogen groups to the number of isocyanate groups is 0.5 to 1.5, preferably 0.8 to 1.2. Further, as a molding method, there are spray foaming, injection molding, laminate molding and the like, which can be integrally processed and commercialized on site. Thermoplastic foams are generally made by melting thermoplastics such as polystyrene, polyethylene, polyvinyl chloride, etc., and adding a crosslinking agent, curing agent, plasticizer, etc.,
It is manufactured by adjusting the viscosity and foaming. Foaming, for example,
Using inert gas (CO ₂ , N _2, etc.), decomposable foaming agent (4,4-oxybisBSH, azodicarbonamide, etc.), volatile organic liquid (propane, butane, etc.) as a plastic raw material under pressure. It can be carried out by impregnation and absorption. Thermosetting plastic foams, for example, phenol resin, urea resin, melamine resin, etc. in a liquid state of low viscosity, while increasing the viscosity by poly-condensation, to an appropriate viscosity, volatile organic Dissolve a liquid in the raw material to generate gas, or mix a foaming agent (ABS-based air set (product name, Takenaka Oil & Fats Co., Ltd.)) with water and stir to generate gas to foam. Meanwhile, it can be prepared by curing.

In order to produce a flame-retardant foam using the powdery flame retardant of the present invention, the powdery flame retardant may be added to the foam material before foaming, mixed well, and then foamed. .
The powdery flame retardant is preferably added to the main agent. For example, a kit (Kraft Resin urethane urethane soft N, manufactured by Kokusai Chemical Co., Ltd.) that can easily mold a urethane foam is commercially available, and a flame-retardant foam can be prepared using this kit. This kit is composed of a liquid polyether polyol as a main component and a liquid containing 4,4′-diphenylmethane diisocyanate as a curing agent. Therefore, the powdered flame retardant may be added to the main agent and stirred, and then the curing agent may be added and stirred and poured into the mold. The addition amount of the powdery flame retardant is not particularly limited. Depending on the foam material to be applied, the addition amount may be appropriately changed while considering the balance between the flame retardancy and the hardness or cushioning property of the foam. For example, when using the above kit, it is preferred to mix in the foam material in an amount of 2 to 60% by weight, preferably 5 to 20% by weight, based on the total weight of the urethane foam material. The higher the content of the powdery flame retardant, the harder the urethane foam becomes. Therefore, if the content is adjusted within this range, the degree of flame retardancy and the appropriate hardness or cushioning property of the urethane foam can be adjusted. The flame-retardant foam of the present invention not only has remarkably excellent flame retardancy, but also does not require a separate step such as impregnation, and does not require any special technique or device, and is simple. It can be prepared by operation. Therefore, it is possible to prepare the flame-retardant foam of the present invention by adding a powdery flame retardant to the foam material on the spot, performing a chemical reaction for foaming, and directly molding and curing it at the construction site. .

On the other hand, the method for producing the flame-retardant foam of the present invention may be a method of impregnating it with an aqueous solution of a powdery flame retardant. In this case, the powdery flame retardant is first dissolved in water to prepare an aqueous solution of the powdery flame retardant, which is then impregnated into a foam having a desired shape, and then dried to obtain a flame retardant. A flammable foam can be produced. This production method by impregnation is particularly useful when there is a long heating step or exothermic step when producing a foam. Since the powdery flame retardant of the present invention may have reduced flame retardancy when subjected to a heat load higher than 70 ° C. for a long time,
In the case of a thermoplastic plastic foam or a thermosetting plastic foam that has a process of becoming high heat, the method of manufacturing a flame-retardant foam by directly adding the powdered flame retardant to the foam material before foaming is applied as it is. Difficult to do. For example, in the case of producing a foam using thermoplastic polyethylene as a main component, about 120 to 130 ° C. is applied in the step of melting polyethylene and mixing the foaming agent, and about 2 in the step of heat foaming.
It can be as high as 00-210 ° C. It should be noted that even in the foaming process of polyurethane in the above-mentioned commercially available kit, heat is generated, but about 80
Since it is not heated at about 100 ° C. for a long time and is naturally cooled after that, reduction in flame retardance does not pose a problem. The aqueous solution of the powdery flame retardant is suitably dissolved in water in an amount of 0.1 to 40% by mass, preferably 5 to 30% by mass, based on the total mass of the aqueous solution of the powdery flame retardant. The powdery flame retardant of the present invention may be directly dissolved in water, or ammonium chloride and pentaerythritol are dissolved in water while the dicyandiamide is dissolved so that the mixing ratio is the same as that of the powdery flame retardant of the present invention. After mixing these solutions, propylene glycol may be dissolved to prepare a stock solution, which may be diluted to a concentration of 0.1 to 40% by mass. Further, when impregnating the previously prepared foam with the aqueous solution of the flame retardant, the compression and relaxation are repeated several times with a hand so that the foam contains the aqueous solution of the flame retardant. Preferably. A flame-retardant foam is obtained by squeezing the foam well to remove excess flame retardant and drying. Even if the liquid flame retardant of the present invention is used, a flame retardant foam can be produced by the same method. Furthermore,
The aqueous solution of the powdery flame retardant can impart flame retardancy to various materials by so-called post-processing. For example, a flame-retardant material can be easily prepared by applying an aqueous solution of a powdery flame-retardant agent to a building material such as wood, a textile product such as paper or cloth, other synthetic materials, metal, etc. Further, even if the liquid flame retardant of the present invention is used, a flame retardant material can be produced by the same method. In addition, when a wood test piece obtained by impregnating cypress with an aqueous solution of a powdery flame retardant was subjected to a quasi-noncombustible material test in accordance with ISO standards at the Foundation for Building Materials Testing Center, no flame was found and it was harmful for fire prevention. No cracks or holes penetrating to the back surface were observed, and the total calorific value of the wood test piece for 10 minutes was 3.5 MJ / m ² , and 8 MJ / m ² or less was below the standard for passing the quasi-incombustible material test. , Has obtained the judgment result of passing the quasi-noncombustible material test. In this way, it is possible to impart flame retardancy to existing foams with extremely simple operation without using special equipment, so even in construction sites and manufacturing sites, foams with excellent flame retardancy can be obtained. It can be made and is very convenient.

[0011]

The present invention will be described in more detail with reference to Examples and Comparative Examples. Example 1 61.9 g of ammonium chloride, pentaerythritol 1
7.6 g, dicyandiamide 17.5 g and propylene glycol 0.2 g were mixed to prepare a powdery flame retardant. Next, using the above-mentioned commercially available urethane foam manufacturing kit manufactured by International Chemical Co. (product name urethane foam soft N),
Liquid A agent 100 containing polyether polyol as a main agent
Add 23 g of powdered flame retardant to g and stir well, add 56 g of liquid B agent containing 4,4′-diphenylmethane diisocyanate as a curing agent to this, and stir and pour into a mold (inner diameter 6 cm × 7 cm × 20 cm) , Foam,
An approximately rectangular parallelepiped flame-retardant foam having a size of about 6 cm × 7 cm × 20 cm and slightly expanding in a pound cake shape was obtained. This was cut into a size of 6 cm in length × 7 cm in width × 1 cm in thickness to obtain a foam sample A-1. [Flame Retardancy Test] The end of this foam sample A-1 is sandwiched by a metal clip, and the metal clip is fastened to the metal rod with cellophane tape so that the foam sample A-1 hangs vertically from the metal rod. , Gas burner (manufactured by Yoshinaga Co.,
The foam sample A-1 was installed at a position 250 mm from the GT-5000) injection port, and the flame temperature of the gas burner was 1500 ° C.
Foam sample A-1 under conditions of room temperature 25 ° C. and humidity 60%
A flame of a burner was radiated to observe the burning state of the foam sample A-1. Example 2 123.8 g of ammonium chloride and 35.2 g of pentaerythritol were dissolved in 1 L of water. 35.0 g of dicyandiamide was dissolved in another 1 L of water. These aqueous solutions were mixed to dissolve 0.4 g of propylene glycol to obtain an aqueous solution of flame retardant. This flame retardant aqueous solution 150
The diluted flame retardant aqueous solution was obtained by taking 1 ml and diluting it with 850 ml of water. Shinwa Co., Ltd. polyurethane foam (soft) was cut into a size of 6 cm in length × 7 cm in width × 2 cm in thickness. The thickness is different from that of the first embodiment.
This is because the commercially available polyurethane foam had a thickness of 2 cm and was used as it was. While compressing and relaxing the cut foam by hand, the foam was impregnated with the diluted flame retardant aqueous solution, the foam was squeezed well to cut the aqueous solution, and then air-dried to obtain foam sample A-2. The foam sample A-2 was placed on a metal rod in the same manner as in Example 1 except that the metal clip was attached to the metal rod with cellophane tape so that the foam sample A-2 was placed on the metal rod. A sex experiment was conducted. The reason why the foam sample was placed on the metal rod was that when the foam sample B-3 of Comparative Example 3 corresponding to the present Example 2 was hung, the foam sample immediately melted and fell off so that it could be sufficiently observed. First, B-3 was set on the metal rod, and thus this was adapted. Comparative Example 1 A foam was obtained in the same manner as in Example 1 except that the powdery flame retardant was not added. This was cut into a size of 6 cm in length × 7 cm in width × 1 cm in thickness to obtain a foam sample B-1.
A flame retardancy test was conducted in the same manner as in Example 1. Comparative Example 2 A memory foam (polyurethane foam) manufactured by Yamamitsu Oil Industry Co., Ltd. was cut into a size of 6 cm in length × 7 cm in width × 1 cm in thickness to obtain a foam sample B-2. A flame retardancy test was conducted in the same manner as in Example 1. The memory foam is commercially available as a urethane foam having a self-extinguishing property. Comparative Example 3 Shinwa Co., Ltd. made of polyurethane foam (soft) 6 in length
It was cut into a size of cm × width 7 cm × thickness 2 cm to obtain a foam sample B-3. A flame retardancy test was conducted in the same manner as in Example 2.

[Results] Example 1 When a flame of a burner was radiated to the foam sample A-1 for about 45 seconds, the surface of the foam sample A-1 was slightly browned and carbonized. There was no flame, no burning, no holes. Example 2 When a flame of a burner was radiated to the foam sample A-2 for about 1 minute, the surface of the foam sample A-2 was carbonized slightly brown, and no flame was emitted from the foam sample A-2. , It didn't burn at all and it didn't puncture. Comparative Example 1 When a flame of a burner was radiated to the foam sample B-1 for about 10 seconds, the foam sample B-1 burned violently and spread, and the foam sample B-1
The foam sample B-1 fell off the metal rod 40 seconds after -1 was melted to form a drip and the burner was emitted. Comparative Example 2 When a flame of a burner was radiated to the foam sample B-2 for about 35 seconds, a small amount of flame was first generated and then no flame was generated. Was carbonized black. Comparative Example 3 When a flame of a burner was radiated to the foam sample B-3 for about 20 seconds, the foam sample B-3 burned violently and spread the fire immediately, and the foam sample B-3 melted to cause drip, resulting in foam. The entire sample B-3 was melted.

[0013]

According to the present invention, it is possible to obtain a powdery flame retardant capable of imparting excellent flame retardancy to a foam by a simple operation. Moreover, when this powdery flame retardant is used, a flame-retardant foam can be produced by a simple operation.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08K 5/053 C08K 5/053 5/315 5/315 C08L 101/00 C08L 101/00 C09K 21/06 C09K 21/06 21/10 21/10 F term (reference) 4F074 AA17 AA32 AA58 AA78 AC28 AD04 AD13 AG10 BA13 BA20 BA36 BA37 CD20 DA18 DA32 DA35 4H028 AA04 AA24 AA29 BA06 4J002 BB021 BC021 BD031 CC021 CC161 CC181 CK021 EC036 DF026 EC026 EC026 EC036 EC0 GN00

Claims (5)

[Claims] 1. To 100 parts by mass of ammonium chloride, 20 to 40 parts by mass of pentaerythritol, 20 to 40 parts by mass of dicyandiamide and 0.2 to 0.6 parts by mass of propylene glycol are contained, and sodium tungstate, ammonium sulfate, A powdery flame retardant characterized by not containing formaldehyde urea and ammonium monophosphate. 2. Ammonium chloride 1.0 to 30.0% by mass, pentaerythritol 0.5 to 10.0% by mass, dicyandiamide 0.5 to 10.0% by mass, propylene glycol 0.01 to 0.2% by mass. % And water 49.8-9
7.99% by mass of sodium tungstate,
A liquid flame retardant characterized by not containing ammonium sulfate, formaldehyde urea and ammonium monophosphate. 3. The liquid flame retardant according to claim 2, which is used by diluting the liquid flame retardant 2 to 20 times with water. 4. A method for producing a flame-retardant foam using the powdery flame retardant according to claim 1, wherein the powdery flame retardant is mixed with a foam material, and then the foam material is mixed with the foam material. A manufacturing method characterized by foaming. 5. A method for producing a flame-retardant foam using the powdery flame retardant according to claim 1, wherein the powdery flame retardant is based on the total mass of the aqueous solution of the powdery flame retardant. 0.1% to 40% by mass of the compound is dissolved in water, an aqueous solution of the powdery flame retardant is impregnated with a foam, and the mixture is dried.