JPS6297999A - Fire retardant paper excellent in heat setting property - 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 relates to flame-retardant paper with excellent heat setting properties.

Conventionally, as a method for manufacturing general paper or mica-containing paper, a method of forming cellulose fibers or an aqueous slurry in which mica is mixed with cellulose fibers is known. However, the paper produced by this method does not have heat setting properties, so if heat setting is required, the paper stock should be soaked in a resin such as phenol resin, melamine resin, urea resin, etc.
Approximately 60% of the material is adhered, pre-dried, formed into the desired shape, and heated in a heating furnace for heat setting. Furthermore, these papers have the disadvantage of being combustible because they use cellulose fibers.

If flame retardancy is required, methods such as spraying or soaking paper with an aqueous solution of flame retardants such as ammonium phosphate, ammonium sulfaminate, guanidine phosphate, guanidine sulfamate, borax, and boric acid can be used. It is being said. However, paper treated with flame retardant treatment using this method has poor texture. Especially when placed in a humid atmosphere.
Due to moisture absorption, the texture deteriorates, hardness and electrical resistance decrease, and metals in contact with the paper corrode, among other disadvantages.

In addition, if both heat setting properties and flame retardancy are required, general paper is immersed in a processing liquid made by dissolving halogenated phosphate ester etc. in a methanol solution of phenolic resin, and pre-dried.
After forming into the desired shape, it is heat set in a heating furnace.

In this case, about 60% flame retardant and 1
Since it is necessary to deposit 0 to 60% phenolic resin, the original properties of the paper are often lost. In order to eliminate these drawbacks, the inventors have conducted extensive research and found that
We have discovered a paper that can simultaneously provide heat-setting properties and flame retardancy, which were considered impossible with conventional paper.

The present invention uses 50 to 1000 parts by weight of mica and 4 to 100 parts by weight of aluminum hydroxide to 100 parts by weight of cellulose fiber.
It is a flame-retardant paper with excellent heat-setting properties, which is characterized by containing 2 to 40 parts by weight of antimony trioxide and 4 to 60 parts by weight of chlorinated paraffin with a chlorine content of 65% or more.

The flame retardant paper of the present invention contains 50 to 1000 parts by weight of mica and 4 to 1 part by weight of aluminum hydroxide per 100 parts by weight of cellulose.
An aqueous slurry containing 00 parts by weight, 2 to 40 parts by weight of antimony trioxide, and 4 to 60 parts by weight of chlorinated paraffin having a chlorine content of 65% or more can be produced by papermaking.

When producing the flame-retardant paper of the present invention, there is no need for special equipment for applying heat-setting agents or flame retardants, and conventional mica paper-making equipment can be used as is. Further, the flame-retardant paper of the present invention can be processed into any shape, such as a sheet, a honeycomb, a pipe, or a ribbon.

The cellulose fiber used to produce the flame-retardant paper of the present invention refers to cellulose fiber produced from pulp, and includes regenerated cellulose fiber such as rayon, haasbest,
It may contain inorganic fibers such as rock wool and glass fibers.

Examples of the mica used in the present invention include muscovite-based mica, such as muscovite, red mica, soda mica, sericite, vanadium mica, illite, etc., biotite-based mica, such as biotite, phlogopite, iron mica, Chinwald mica, etc. Examples include mica. The composition of these mica is shown below. Phlogopite KMg.

(A1si3oI(1) (OH)2, Muscovite KA12
(AISi3010) (OH)2, soda mica HaA
1□ (AISi301g) (OH)2,ll Biotite (K2 MgFe Fe )a (5IA1)8
020(0”0H)4%, lepidolite K Li2A l
(S i40.o) (OH)2, synthetic fluorophlogopite K
Mg3 (An Si30,6) F2, synthetic fluorine tetrasilicon mica KMg24 (5i4010) F2゜ Mica, aluminum hydroxide and antimony trioxide can be commercially available products, but these particles have a particle size of 50 mesh or less, Particularly preferred is one having a mesh size of 1°O or less. If the particle size is larger than 50 mesh, the surface of the resulting flame-retardant paper may become rough. Further, it is preferable to use chlorinated paraffin having a chlorine content of 65% or more and a particle size of 50 mesh or less, but there is no problem even if powder with a particle size larger than 50 mesh is mixed.

The chlorinated paraffin powder used in the present invention has a chlorine content of 65% or more. If chlorinated paraffin with a chlorine content of 65% or less is used, the flame retardant effect will be weakened, and the chlorinated paraffin will soften at room temperature, making it difficult to powder (and making papermaking at room temperature difficult).

When producing the flame-retardant paper of the present invention, first, 50 to 1000 parts of mica, 4 to 100 parts of aluminum hydroxide, 2 to 40 parts of antimony trioxide, and a chlorine content of 65% are prepared based on 100 parts of cellulose fiber. An aqueous slurry containing 4 to 60 parts by weight of the above chlorinated paraffin is prepared. If the amount of mica, aluminum hydroxide, antimony trioxide or chlorinated paraffin is less than this, sufficient flame retardancy and heat setting properties cannot be obtained. Moreover, if the blending amount of these components is larger than this, the strength and heat setting properties of the resulting flame-retardant paper will be reduced.

Various additives used in general paper making may be added to this aqueous slurry. Examples of additives include paper strength enhancers, wet paper strength enhancers, retention improvers,
P water improver, fixing aid, sizing agent, coloring agent, matting agent,
Examples include light resistance improvers and auxiliary agents. There are no restrictions on the order of addition, the method of addition, etc.

Next, when this aqueous slurry is made into paper using a conventional method, a flame-retardant paper with excellent heat setting properties is obtained.

The flame retardant paper of the present invention is heated at a temperature of 100°C or higher, preferably 120°C or higher.
Heat setting can be achieved by heating to a temperature of C or higher. Conventional mica-containing paper obtained by making paper from an aqueous slurry of cellulose fibers and mica does not exhibit heat-setting properties.

Also, when using only aluminum hydroxide, only antimony trioxide, or only chlorinated paraffin powder, no heat setting property is shown. The reason that heat-setting properties can only be obtained by forming paper in the coexistence of these components is presumed to be due to some effect of the combination of the layered structure of mica, aluminum hydroxide, antimony trioxide, and chlorinated noglyphin. be done.

Comparing the flame retardant paper of the present invention with conventional mica-containing paper and kraft paper in terms of heat-setting properties, in the case of conventional kraft paper and mica-containing paper, the original paper is first immersed in a methanol solution of phenolic resin to impregnate it. However, paper is used which has been pre-dried at 80 to 100° C. with a processing liquid applied to the original paper in an amount that is apparently 100%. Heat set condition is 160°
It takes 25 to 60 minutes at C. On the other hand, the flame retardant paper of the present invention can be used as is, and the heat setting condition is 120
~160°C for 25 minutes. As described above, the flame-retardant paper of the present invention does not need to be impregnated with or added to a phenolic resin, and can be heat-set even at a lower heating temperature than a paper to which a phenolic resin is added. Furthermore, the flame-retardant paper of the present invention has good heat setting properties and good shape.

Example 1 One part of water was added to a pulper (disintegrator) equipped with a stirring device, a thermometer, etc.
After dissolving 9 in 0.6 of caustic soda, 9 kg of Kraft Valve was added to prepare a slurry.

To this slurry were added 15 kg of mica powder (muscovite, particle size of 200 mesh or less, approximately 10 to 150 μ), 1.2 kg of antimony trioxide (particle size of 2 to 6 μ), and 2.4 kg of aluminum hydroxide powder (particle size of 50 to 60 μ). kg, chlorinated rough-in powder (chlorine content 70%, softening point 95~
At 105°C, 2.4 kq (particle size: 50 mesh or less) was added while stirring to form a uniform slurry. Next, 0.1 kg of a cationic paper strength enhancer was added, and then sulfuric acid band (8% aqueous solution) was added to adjust the pH to 6.5. Furthermore, paper strength enhancer (anionic acrylamide type) 0.
1 kg and 0.007 kg of acrylamide cationic fixative, a slurry with a consistency of 6% is obtained. This slurry was diluted to a concentration of 0.2%, sent to a paper making machine, dried using a Yankee twin dryer at 100°C, and then wound up on a winding machine, resulting in a basis weight of 11 sy/m2. flame retardant paper was obtained.

The obtained flame-retardant paper was stretched into a honeycomb shape and heated at 120°C for 2 hours.
Heat set for 5 minutes. After the heat-set honeycomb was immersed in water at room temperature for 48 hours, it was dried at 100°C for 10 minutes, and the honeycomb shape was visually observed and its diameter measured, but it did not differ from the original shape.

Using the flame retardant paper thus obtained as is, JISL-1
When a combustion test was conducted using the 091A-4 method, the char length was 7 to 8 CIn, the afterflame was 0 seconds, and the residual flame was 0 seconds. Moreover, the limiting oxygen index (L○ engineering) was 60.0.

In addition, after setting the honeycomb to heat, it was immersed in water for 48 hours, then the dried honeycomb was placed in water, and an alcohol lamp was lit for 5 seconds at the corner of the cut end of the honeycomb shape, and the afterflame was measured. It was 0 seconds.

Comparative Example 1 A slurry containing kraft pulp and mica was prepared in the same manner as in Example 1 except that antimony trioxide, aluminum hydroxide and chlorinated paraffin were not used,
This slurry was made into paper to produce mica-containing paper. When a combustion test was conducted using this mica-containing paper, it completely burned down and the limiting oxygen index was 25.5. When this paper was spread out into a honeycomb shape and heat set at 160°C for 60 minutes,
It was not possible to produce honeycomb.

Comparative Example 2 Aluminum hydroxide and chlorinated paraffin were not used,
Otherwise, a slurry containing pulp, mica, and antimony trioxide was prepared in the same manner as in Example 1, and this slurry was made into paper to produce mica paper. The combustion test results and heat setting properties of this mica-containing paper were the same as those of Comparative Example 1.

Comparative Example 3 A slurry containing pulp, mica, and aluminum hydroxide was prepared in the same manner as in Example 1 except that antimony trioxide and chlorinated paraffin were not used, and this slurry was made into paper to produce mica-containing paper. did. The combustion test results and heat setting properties of this mica-containing paper were the same as those of Comparative Example 1.

Comparative Example 4 Antimony trioxide and aluminum hydroxide were not used,
Otherwise, a slurry containing pulp, mica, and chlorinated paraffin was prepared in the same manner as in Example 1, and this slurry was made into paper to produce mica-containing paper. The combustion test results and heat setting properties of this mica-containing paper were the same as those of Comparative Example 1.

Comparative Example 5 A slurry containing pulp, mica, antimony trioxide, and aluminum hydroxide was prepared in the same manner as in Example 1 without using chlorinated paraffin, and this slurry was made into a paper containing mica. Manufactured. The combustion test results and heat setting properties of this mica-containing paper were the same as those of Comparative Example 1.

Example 2 Flame-retardant paper was produced in the same manner as in Example 1 except that recycled kraft waste paper was used instead of the kraft pulp used in Example 1. The basis weight of the obtained flame-retardant paper was 175 g/m2. Heat setting and combustion tests were conducted in the same manner as in Example 1. Comparative Examples 6-1 manufactured in the same manner as Comparative Examples 1-5
A similar test was also conducted on paper containing mica No. 0. The results are shown in Table 1.

Table 1 Example 6 Using the same equipment as in Example 1, 1 kg of caustic soda was dissolved in 2500 kg of water, and 15 kg of kraft pulp and 15 kg of recycled kraft waste paper were added to prepare a pulp slurry. Next, 40 kg of mica powder (phlogopite particle size of 200 mesh or less) and 20 kg of synthetic mica (fluorotetrasilicon mica manufactured by Tobi Industries, Ltd., 200 mesh or less) were added. In addition, 4 kg of antimony trioxide powder, 8 kg of aluminum hydroxide and chlorinated paraffin (chlorine content 70
%, softening point 95°C) was added to prepare a uniform slurry. This slurry contains 0.0% cationic paper strength enhancer.
After adding 4 kg, bandate sulfate (8% aqueous solution) was added to adjust the pH to 6.5, and then 0.3 kg of paper strength enhancer (anionic acrylamide type) and 0.02 kg of acrylamide cationic fixer were added. added. This slurry was sent to a paper-making machine and paper-made under the same conditions as in Example 1 to produce flame-retardant paper. This flame retardant paper had a basis weight of 17 m2. A honeycomb was produced according to the honeycomb work process. Heat set was 120°C for 25 minutes. Heat setting and combustion tests were conducted in the same manner as in Example 1. Similar tests were conducted on the mica-containing papers of Comparative Examples 11 to 14, which were produced in the same manner as Comparative Examples 1 to 4, and the mica-containing paper of Comparative Example 15, in which antimony trioxide was removed from this example. The results are shown in Table 2.

Table 2 Example 4 Using the same equipment as in Example 1, 10,001 liters of water was charged into a pulper, 0.3 kg of caustic soda was dissolved, and 5 kg of kraft waste paper was added to prepare a slurry. Add to this slurry 24 kg of mica powder (muscovite, particle size 200 mesh or less), antimony trioxide (particle size 2 to 6
μ) 1 kg, aluminum hydroxide 2 kg and chlorinated paraffin powder (chlorine content 70%, softening point 95-105
1.5 kg (1.5 kg (°C 1 particle size: 50 mesh or less)) was added to make a uniform slurry. Next, 0.2 kg of a cationic paper strength enhancer was added, and sulfuric acid bandate (8% aqueous solution) was added to adjust the pH to 6.5. Furthermore, 0.2 kq of paper strength enhancer (anionic acrylamide type) and 0.01 kq of acrylamide type cationic fixing agent were added. This slurry was diluted to a concentration of 0.2%, sent to a paper making machine, and made into paper under the same conditions as in Example 1 to produce flame retardant paper. This flame retardant paper had a basis weight of 110 g/rrL2. Heat setting and combustion tests were conducted in the same manner as in Example 1. Similar tests were also conducted on the mica-containing papers of Comparative Examples 16 to 20, which were manufactured in the same manner as Comparative Examples 1 to 5. The results are shown in Table 6.

Table 6

Claims (1)

[Claims] 50 to 10 mica per 100 parts by weight of cellulose fiber
00 parts by weight, 4 to 100 parts by weight of aluminum hydroxide, 2 to 40 parts by weight of antimony trioxide, and 4 to 60 parts by weight of chlorinated paraffin with a chlorine content of 65% or more. Excellent flame retardant paper.