JPS61124699A - Fire retardant composition excellent in heat stability - 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 Field of the Invention The present invention relates to flame retardant compositions for paper. For more details,
The present invention relates to a flame retardant composition for paper which, when applied to paper, provides flame retardant paper with excellent flame retardancy and thermal stability.

[Conventional technology]

Guanidine salts such as guanidine sulfamate, guanidine sulfate, and guanidine phosphate have been widely used as flame retardants for cellulose products since they have excellent flame retardant properties.

Flame-retardant paper processed using these flame retardants is mainly used as building material paper such as wallpaper or fusuma paper. When the flame retardant is heated to process it into paper for building materials, it is particularly important that the flame retardant has excellent thermal stability for the paper.

Therefore, in order to make the above-mentioned flame retardant excellent in thermal stability while maintaining its original flame retardancy, it is proposed that the guanidine salt described in E be made into a specific composition or that additives be added. has been done.

For example, Japanese Patent Publication No. 52-25448 discloses a composition comprising at least one compound selected from a, ammonium sulfaminate, b, guanidine sulfamate, and C, dicyandiamide, a methylolated product of dicyandiamide, and hexamethylenetetramine. is suggesting.

Furthermore, Japanese Patent Publication No. 58-29344 proposes a method in which dicyandiamide is mixed with guanidine sulfamate obtained by subjecting dicyandiamide and ammonium sulfamate to a heat-melting reaction at a molar ratio of 1:2.

Furthermore, JP-A-58-115380 proposes a method in which an equivalent amount of alkali is added to the ammonium salt present in guanidine sulfamate.

However, in the method of manufacturing wallpaper, heating conditions have become stricter, such as increasing the number of heating cycles in order to improve productivity or diversify the surface of wallpaper by raising the processing temperature. Compositions or methods such as (2) do not give satisfactory results with regard to the thermal stability in question.

Regarding the above-mentioned item (1), although ζ is satisfied in terms of thermal stability, the pH of the aqueous solution of the flame retardant becomes high, for example, 9, which may cause other problems in flame retardant processing.

As a suggestion other than the above ■~■, for example, the following tl x
I can list t. That is, (1) a method of adding a melamine-formaldehyde reaction product or a melamine-formaldehyde-alcohol reaction product to guanidine sulfamate (Japanese Patent Application Laid-Open No. 53-1253i15).
) or ■ A method of adding a urea-formaldehyde-alcohol reaction product to guanidine sulfamate (
#opening 58-117G). However, in these methods, the aqueous solution of melamine or urea as an additive reacted with formaldehyde, or the additive further reacted with alcohol, is unstable, and insoluble matter is generated or gelation occurs before use. may occur.

Therefore, in order to obtain a stable additive, consideration must be given to reducing the reaction amount of formaldehyde or adding alcohol to the reaction product. the result,
In addition to increasing the proportion of additives other than the flame retardant used in the flame retardant compositions according to the above methods, problems such as the generation of alcohol vapor during use occur. Therefore, the method (1) or (2) above cannot be said to be a satisfactory method.

[Purpose of the invention]

The present inventors have conducted various studies in order to find a flame retardant composition that provides good flame retardant properties to treated paper and excellent thermal stability of paper during processing.

As a result, the amount of the main component of guamidine salt, which has flame retardant properties,
A flame retardant composition containing an additive amount of a reaction product of a carbonyl compound having hydrogen at the α position and formaldehyde satisfies the above technical requirements, and also solves the problems of the known techniques described in (■) to (■) above. The present invention was completed knowing this.

As is clear from the above description, an object of the present invention is to provide a flame retardant composition for paper that exhibits good thermal stability of paper when processed into paper and flame retardant properties of processed flame retardant paper. There is something to do.

[Structure of the invention]

The present invention has the following configuration.

A paper flame retardant whose main component is guanidine salt, which has flame retardant properties, has excellent thermal stability due to the amount of several main components and the amount of an additive of a reaction product of formaldehyde and a carbonyl compound having hydrogen at the α-position. Flame retardant composition for paper.

The guanidine salt having flame retardant properties used as the main component of the flame retardant composition of the present invention refers to the following compound or reaction mixture, namely, guanidine sulfamate 7
A compound selected from guanidine sulfate, guanidine phosphate, or condensed guanidine phosphate, or a combination of two or more compounds, or a compound selected from the following four types of compounds or a combination of two or more compounds in dicyandiamide. This is a reaction mixture obtained by the reaction. The four types of compounds are ammonium sulfamate, ammonium sulfate, ammonium phosphate, or condensed ammonium phosphate. Moreover, instead of these four types of compounds, a combination of a corresponding inorganic acid and ammonia can also be used for producing a reaction mixture for dicyandiamide.

α used as an additive component of the flame retardant composition of the present invention
The reaction product of a carbonyl compound having hydrogen at the position and formaldehyde refers to the reaction mixture of
carbonyl compounds such as lower aliphatic aldehydes such as acetaldehyde, zolopionaldehyde, normanbutyraldehyde or isobutyraldehyde;
Lower aliphatic ketones such as acetone, methyl ethyl ketone or diethyl ketone. malonaldehyde,
Dialdehydes such as succinic aldehyde or those having functional groups other than carbonyl groups in the molecule, such as hydroxyl groups, amine groups, or carboxyl groups, can also be used.

A reaction product obtained by reacting these carbonyl compounds with formaldehyde is used as an additive component of the composition of the present invention. The reaction conditions are such that α of 1 mol of the carbonyl compound is
Use 0.5 to 2.5 mol of formaldehyde, preferably 1.0 to 2.0 mol, per hydrogen atom in the aqueous solution.
The reaction is carried out at 80°C, preferably 30-80°C, for 0.5-5 hours, preferably 1-3 hours. During this time, the pH of the reaction mixture is preferably maintained at 6-9. When the pH is less than 7, the condensation reaction proceeds, a large amount of water-insoluble products are produced as by-products, and the usability as a paper flame retardant composition is ultimately reduced. On the contrary, P
Above H9, the thermal stability of the final composition may decrease.

In the above reaction, a maximum of 1 mole of formaldehyde reacts with the hydrogen atom at the α-position of the carbonyl group of the carbonyl compound. On the other hand, unreacted or excess formaldehyde is consumed by the coexisting alkali and causes the Cannitzaro reaction, or remains unreacted, causing the final composition to emit an irritating odor, thus reducing the thermal stability of the composition. This results in a composition with poor practicality regardless of its properties.

Therefore, it is necessary to adjust the molar ratio of the carbonyl compound and formaldehyde and other reaction conditions so that as little unreacted formaldehyde remains as possible.

However, even if unreacted formaldehyde remains, the problems associated with the remaining formaldehyde can be solved by subjecting the above-mentioned reaction mixture to the following treatment as an embodiment/aspect of the present invention.

That is, a nitrogen-containing organic compound having active hydrogen is reacted with a reaction product of a carbonyl compound having hydrogen at the α-position and formaldehyde, which is an additive component according to the present invention,
Unreacted formaldehyde can be eliminated. Therefore, the amount of active hydrogen in the nitrogen-containing organic compound used needs to be at least equivalent to the molar ratio of unreacted formaldehyde.

Examples of such nitrogen-containing organic compounds include dicyandiamide, urea, thiourea, guanidine, guanamine, melamine, and homologs thereof. The reaction conditions for the above reactant and the nitrogen-containing organic compound are (temperature,
Time) The reaction conditions are the same as those for the reaction of a carbonyl compound and formaldehyde described above, and can be carried out as a treatment subsequent to the reaction.

Other additive components that can be used in combination with the composition of the present invention include:
The following compounds may be mentioned. That is, for example, polyhydric alcohols such as pentaerythritol, trimethylolpropane, propylene glycol, dicyandiamide, urea, melamine or guanamine or methylolated products thereof. By appropriately using these additive components in combination with the reaction product of a carbonyl compound and formaldehyde according to the present invention or its nitrogen-containing organic compound-treated product, the thermal stabilization effect of the composition of the present invention can be further improved. .

The composition of the invention is prepared or mixed in an aqueous state.

In order to produce a flame retardant composition that can produce flame retardant paper that maintains flame retardant performance and a high degree of thermal stability, it is necessary to combine the main component, i.e., a flame retardant guanidine salt, and the additive component, i.e., the carbonyl compound mentioned above. and formaldehyde reactant quantity ratio (
weight ratio) is important. The ratio is 0.5 to 20 parts, preferably 1 to 10 parts of the latter to 100 parts of the former. If the amount of additive components is less than 0.5 part,
It is difficult to improve the thermal stability of the target composition, and if the amount exceeds 20 parts, the thermal stability will improve, but the flame retardant effect will decrease, so This necessitates a significant increase in usage rates, resulting in
The quality of the obtained flame retardant paper deteriorates, and increasing the proportion of flame retardant used is not economical.

The additive component of the composition of the present invention is a reaction product of the above-mentioned carbonyl compound and formaldehyde, which are essential components, or a reaction product of the above-mentioned nitrogen-containing compound to the reaction product, and the above-mentioned other additions, which are optional components. It consists of drug ingredients (note: pentaerythritol, etc.). The ratio of the additive component (total amount) to the main component is also 0.00 parts per 100 parts of the latter, as described above.
Use 5-20 parts. The mixing method is not limited as long as the composition of the present invention is finally obtained as an aqueous solution, and the mixing order is not limited.

In addition, the reaction product of a carbonyl compound having hydrogen at the α-position and formaldehyde in the additive component of the composition of the present invention and the other additive components described above (Note).

The ratio of pentaerythritol, etc.) is not limited, as long as the ratio of the former to the main component is 0.5 part or more, but most preferably the ratio is 121 to 0.1 (positive ratio).

The flame retardant composition of the present invention prepared as described above can be used to produce flame retardant paper by impregnating paper as an aqueous solution and then drying and adhering it.

〔Effect of the invention〕

In the present invention, the thermal stability effect is mutually improved by the combination of a guanidine salt having flame retardant properties and the reaction product of the carbonyl compound and formaldehyde described above, and the individual components are different from each other. It is presumed that this effect is due to the mechanism of action.

The composition of the present invention is stable when made into an aqueous solution, and has PI (
Since it is neutral and has sufficient flame retardant and heat stabilizing effects, it does not have the problems of the above-mentioned known techniques (■ to ■) and can be used to efficiently produce high-quality flame-retardant paper. I can do it.

〔Example〕

The test methods in Examples and Comparative Examples were as follows.

(1) Thermal stability test A filter paper was immersed in an aqueous solution of a flame retardant composition, allowed to adhere, and dried to prepare a flame retardant paper. This was heat-treated at 200°C for 3 minutes, 5 minutes, and 220°C for 3 minutes in a hot air circulation dryer, and the whiteness was measured using a Hunter whiteness meter.

The amount of flame retardant adhered was determined according to JIS Z-2150 and passed JIS grade 2 (carbonization length 10 cm or less), and in the case of guanidine sulfamate, 20 parts and 3% of the flame retardant was used.

(2) Flame retardant test JIS Z-215 Or thin material flame retardant test” (45
The test was carried out using the ゜Metzkel burner method) with a flame contact time of 10 seconds.

Example 1 Additive I was produced by adding 28 g of an 85% acetaldehyde aqueous solution to 150 g of a 35% formalin aqueous solution while stirring while maintaining the pH at 7-9.

Guanidine sulfamate standard 10% using 100 parts of guanidine sulfamate and 16 parts of additive (solid content equivalent)
An aqueous solution was prepared, filter paper was immersed and dried to produce flame retardant paper, and a thermal stability test was conducted.

The results are shown in the table.

Example 2 137 g of a 35% formalin aqueous solution was added dropwise to 21 g of an 85% acetaldehyde aqueous solution with stirring while maintaining the pH at 7 to 9, and the reaction was carried out at 80° C. for 1 hour.
g was added thereto and reacted at 80° C. for 1 hour to produce additive (2).

A flame-retardant paper was produced in the same manner as in Example 1 using 100 parts of guanidine sulfamate and 6 parts of additive (solid content), and a thermal stability test was conducted. The results t± are shown in the table.

Example 3 Add 172 g of 35% formalin to 14.5 g of acetone.
The dropwise reaction was carried out under stirring while maintaining H7 to H9. After the addition was completed, the mixture was reacted at around 80° C. for 2 hours to produce additive (2).

A flame-retardant paper was produced in the same manner as in Example 1 using 10 G parts of guanidine sulfamate and 5 parts of the additive (in terms of solid content), and a thermal stability test was conducted. The results are shown in the table.

Example 4 A flame-retardant paper was produced in the same manner as in Example 1 using 100 parts of guanidine sulfamate, 4 parts of the additive (1) produced in Example 2, and 1 part of hexamethylenetetramine, and a thermal stability test was conducted. The results are shown in the table.

Example 5 A flame-retardant paper was produced in the same manner as in Example 1 using 100 parts of guanidine sulfamate, 4 parts of the additive m produced in Example 4, and 1 part of sodium formate, and a thermal stability test was conducted. The results are shown in the table.

Comparative Example 1 A flame-retardant paper was produced in the same manner as in Example 1 using 100 parts of guanidine sulfamate and 8 parts of dicyandiamide, and a thermal stability test was conducted. The results are shown in the table.

Comparative Example 2 Flame-retardant paper was produced in the same manner as in Example 1 using 40 parts of ammonium sulfamate, 10 parts of guanidine sulfamate, and 10 parts of hexamethylenetetramite. (However, the adhesion amount was 18.2%, and the carbonization length was 7.8 cm). The results of the thermal stability test are shown in the table.

Comparative Example 3 Methylolurea was produced by reacting 8.0 g of urea, 18.9 g of 35% formalin, and 6.4 g of methanol at 60° C. for 15 minutes while maintaining the pH at 7 to 9. (However, in this case, water-insoluble material was formed within 1 hour.) Flame-retardant paper was produced in the same manner as in Example 1 using 100 parts of guanidine sulfamate and 5 parts of methylol urea produced above (in terms of solid content). Then, a thermal stability test was conducted. The results are shown in the table.

that's all

Claims (4)

[Claims] (1) A flame retardant for paper whose main component is a guanidine salt having flame retardant properties, with thermal stability consisting of the amount of the main component of the salt and the amount of an additive of a reaction product of formaldehyde and a carbonyl compound having hydrogen at the α-position. A flame retardant composition for paper with excellent properties. (2) The guanidine salt having flame retardant properties is a combination of guanidine sulfamate, guanidine sulfate, guanidine phosphate, condensed guanidine phosphate, or dicyandiamide and any one or more of ammonium sulfamate, ammonium sulfate, ammonium phosphate, or condensed ammonium phosphate. A composition according to claim (1) which is a reaction mixture. (3) Claim (1) uses an additive amount of a reaction product obtained by reacting a carbonyl compound having hydrogen at the α-position with formaldehyde and a nitrogen-containing organic compound having a small amount of active hydrogen. A flame retardant composition for paper as described. (4) The nitrogen-containing organic compound having active hydrogen is dicyandiamide, urea, thiourea, guanidine, guanamine,
The flame retardant composition for paper according to claim (3), which is melamine or a melamine homolog.