JPS62100457A - Aluminous fiber and its production - Google Patents

Abstract

PURPOSE:To obtain a titled fiber having excellent transparency and tensile strength by subjecting a specific fiber precursor to 2 stages of calcination under specific calcination conditions. CONSTITUTION:Colloidal silica as an SiO2 component is added to a basic aluminum chloride soln as an Al2O3 component and if necessary, a chloride (salt) of P, Ba, Sn, Y, Co, Sr, Cr, Zr, or Fe is added as the oxide component of these metals to the soln.; further lactic acid or acetic acid is added as a viscosity adjusting and gelation preventive stabilizer to the soln. and thereafter the soln. is thickened by vacuum distillation to obtain a stock soln. for spinning having 700-3,000p viscosity (ordinary temp.). The soln. is extruded into dry gaseous flow from a vessel having many fine holes sized, for example, about 0.2mm to obtain the fiber precursor. The precursor is first heated to 400-600 deg.C in an NH3 atmosphere and is then subjected to a heat treatment up to 1,200 deg.C in an N2 atmosphere contg. 1-10vol% O2 by which the precursor is executed to two stages of calcination. The titled fiber which is approximately transparent, has >=25kg/mm2 tensile strength and contg. 3-12wt% SiO2 and <=10wt% above- mentioned metallic oxide is obtd.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The invention of ε2 [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 3 or 4 type methods for applying aluminous fibers to navy blue.

[Prior art IU aluminum') Textile fibers are known as TiC. For example, λ is polyaluminum/:l amount of 1 liter, Ni/i1m-[metal compound is produced]P, original old I, -thing is white, q takes 11 sheets of f1 necessary for spinning)IJ Me 141^ Adding molecular compounds! K <11' IIK conversion l・kiru. i
However, each polyalumino resin has an extremely high C height of 1 dli F, and can be made from this r17t l'l. Even though it is expensive, it is expensive!Kome market-C: (7) N and [:L NU Iff KaS
-> k,, also, part 1. i Crab Ag2O3-8i
02 system composition r'205.1120g, Ti 02
It is known that the addition of oxides such as oxides such as oxides such as oxides such as oxides such as oxides such as oxides such as oxides such as oxides such as oxidants such as oxides such as oxidants such as oxides such as oxidants such as oxides such as oxidants such as oxidants such as oxidants such as oxides such as oxides such as oxides such as oxidants such as oxides such as oxides such as oxidants such as Rishi C and high l Fulmino rope Rei Toshi C's function is demonstrated (no 1!? No.

Flumino fibers are made by adding phytosilica to basic aluminum chloride.3!h''Ij? ) h method is known as the applicant's previous 1-i technology (Japanese Patent Application Laid-Open No. 11r
15423727j4). The samurai left the sticky bamboo necessary for spinning, and because of this, the gillf strong turtle made 10Kfl.
/ ttua ” only appears to a certain degree, but structural materials and ()
It is better to use it as a heat insulator than the first one!

1. Means for Solving Problem 1 This invention uses basic aluminum chloride with a high alumina content and silica as starting materials, which are easy to handle, and uses a viscosity adjusting and gelling anti-shrink agent as a starting material. It is used as a WAN precursor by adding lactic acid or acetic acid.

The inventors of the present application conducted a rigorous study on the process of thermal decomposition of this fiber precursor, and found that S
In order to suppress the formation of No. 9, two-stage firing was attempted, and a transparent alumina mu with high tensile strength was obtained.

[Work 1 Hereinafter, this invention will be explained in detail.

In other words, 5102 to 3, 12 pieces +
) 6 (hereinafter referred to as Φ product % - small lJ), and has 13 components 1).

Ba, Sn, Y, Co, Sr, Cr, Ir, l-C tone!
! do. This fiber precursor contains basic aluminum chloride 11Δ(12(ON > 5Cf1) as the Δα203 component.
・2. The second component is 20, and the third component is chloride or salt of the metal oxide.

To these mixtures, lactic acid or acetic acid is added as a stabilizer for adjusting viscosity and preventing gelation. This stock solution is concentrated using a vacuum distillation apparatus to obtain a spinning solution of 3 J, or 700-3000 voise (at room temperature). By adding lactic acid or acid, this spinning solution did not change even if it was left for a long time, and some crystals and precipitates were formed during gelation. By extruding it into a dry air stream from inside a container with many pores, it can be rolled up into a ml roll or the like.

This fiber precursor contains water, hydrogen chloride, lactic acid, or acetic acid, and when heat treated in air, 1! lli
IIIJ I, the cord length shrinks by about 45%.

In the invention of JP-A No. 5123727 mentioned above, there is also the point that the fiber precursor is equivalent to silicon.

Therefore, the present inventors changed the firing conditions to two-stage firing, in which an NH3 gas atmosphere was used in the low temperature range up to 400°C and 600°C, and a nitrogen gas atmosphere with a small amount of oxygen added was used in the high temperature range up to 1200°C. In this second firing, hydrogen chloride remains when treated in water and in air at a low temperature of around 500° 0, and τ is rapidly removed during high-temperature firing, resulting in less pores remaining. The same goes for the carbonization of lactic acid or acetic acid; the primary firing C slowly converts the carbon, and the secondary firing gradually oxidizes it.
It is preferable that

The secondary firing is heated up to 1200°C, and is carried out in a nitrogen gas atmosphere to contain a small amount of oxygen necessary to oxidize carbon. In this case, firing the wA chicks while applying tension is effective in increasing the fiber strength. In other words, they are useful for the oxidation removal of carbon and the formation of fine particles of white clay. Also, P, 11°Sn, Y, Co, Sr, Cr
, 7r, FO (71 oxide or zono l- added U 4
! ? If the fiber content is 10% or less in terms of oxides, especially for 21Q firing, an unprecedented effect can be obtained.

[Effect of the invention 1 This J, the obtained t = the aluminum I fiber of the present invention (the strong m of 1 is 40!?/aa2 or more -1- is 1-7, f'
),, 100Kg/MM2 or more with 7r added
- later obtained t).

A detailed description of the invention is provided below.

Example 1 Salt Mfl Aluminum chloride A (12(ON) 5C
11 Five types of products were obtained in the proportions shown in Table 1. Lactic acid was added to each at a ratio of 20 parts to 100 parts solid content. Concentrate these under reduced pressure with a 1-tally φ■ vaporizer to 700~
A viscous liquid of 3000 voids (room temperature) was obtained. 0.2# on the bottom
The container was placed in a perforated container, pressurized with nitrogen gas, and IIN was extruded through the A-rifice into dry air. After drying this cord precursor, it was dried in a quartz tube at a rate of 1.5%/win of N+-13.
It was fired for 15 minutes at 500°C with gas flowing for 108 minutes. Next, while flowing nitrogen gas containing 1% oxygen at a rate of 5 u/win, the sample was heated to 1200° C. for 2 hours and baked for 15 minutes. As a comparative example, Nn6,
7 Table 1 1 100 0 Crystal growth and powdering Weak and unmeasurable 2 99 1 Crystal growth and powdering Weak and unmeasurable 3 97
3 Slight crystal growth was observed at 70 (1
7.1f)) 4 95 5 Slight crystal growth
64 observed (13,3μ) 6 97 3 Crystal growth/brittle
9 Example 2 The procedure was carried out in the same manner as in Example 1, except that an 85% solution of A13PO4 was added as a P205 source at the ratio shown in Table 2.N
Nos. 16, 17 and 18 were fired in one stage using the conventional method.

1/- Table 2 Experiment Al2O2% Si02% P205 %
Baked Shun's l&1iIff Strong Asan
Observation of Kfl/mAIt
90 7:3 transparent,
17.2μ 11312 95 0
5 Crystal growth, powdering - easy to cause 13 85 12 5)
Transparent 8314 80
17 3 Transparent 2515 80 10
10 Transparent 4816907
ζ3 Crystal growth, brittle 2017
85 12 5 Crystal growth, brittle 1418 80 10
10 Crystal growth, brittleness 17 Example 3 The same procedure as in Example 1 was carried out except that chloride or ins was added at a concentration of 3%, and the physical properties thereof are shown in Table 3. Nos. 111 to 120 were one-stage fired by the conventional method.

Table 3 102 7r20: + Zr0(C, lI2
Transparent 12.27z 1(1!+103
Fe2e3 Fe(j)3 Pale yellow, transparent 51104 Ba OBa (j)2
A light (lI0
5 SnO5n (j14 A light 13.9/j 70106 Y2 03
Y (C)bcOOH)3 i old
Light 11.0μ 1)! )t07
CoOC0 (J2i111 inner color, transparent 13.6fl
Song) 8108 Sr OSr (E, I12
Transparent 13. ! 1/171109
Y2O3Y (C11sC0011) 318 coloration 1:1
．． 177 81+
Transparent Co OCo CM 2 110 Y203 Y (CH3COOH)3
Transparent 12.31194112.14z 112 7r203.7rOCρ2 Crystal formation i
% I2.2I121113 Fe 203
F-e cn:i Pale yellow, due to crystal formation-
101148a (') Ha O,Q 2
Crystal growth 13115 Ω to Sn OS11
4 Crystal growth 13. J114116 Y2
03 Y (0fbcOOl-1) 3 Crystal formation t* 110/118117 COOCo C,
fl 2 pale color, crystalline 1 (201:i
6μ m18 sro 5r (J2 Crystallization (41:19Iz 14 Table 3 (continued) →-13,1μ Co OCO (J 2 120 Y203 Y (CI-1scOOH)
3 Crystal growth 12.3f121→-7rO27rO2C12 As is clear from these examples, the fibers of the two-stage fired product of the present invention are almost transparent and the tensile strength is 25Kg/11
12 or more can be obtained, especially in the case of N011, 113
It also became Kj/rstn 2.

This is a bundle obtained by firing the above-mentioned J: sea urchin in a two-stage firing process and adjusting the atmosphere to avoid the volatilization state that occurs during the thermal decomposition of sea urchin.

The proportion of oxygen contained in the nitrogen during the second stage high-temperature firing is appropriately selected depending on the amount and state of carbon remaining in the secondary firing, but is 1 to 10% by volume, and the preferred range is 3%.
~5% by volume.

Procedural amendment t! i' (Scheme Showa 1985 Patent Application No. 241092 3,
Relationship between the person making the amendment and Suva Oki Patent applicant, amendment 0
Target e□Fine. (, ゎ明. 工. parent, □IC7) Column (Ayu, -9), Correction contents Teitofan character mountain 1 ■ 3 2 T! 7: (Voluntary) Showa 61
May 270, 1985 Patent Application No. 241092 3, Person making the amendment 2-1 Nihonbashihonmachi, Chuo-ku, Tokyo Name Nitto Building Telephone (241>7'268 Application 7, Contents of amendment/) This application Since the number of inventions is 2,

Claims (2)

[Claims] (1) 3-12% by weight of SiO_2 and 10% by weight or less of P, Ba, Sn, Y, Co, Sr, Cr, Zr, F
containing at least one oxide of e, the remainder being Al_2O_
3, is almost transparent and has a tensile strength of 25kg/mm^
An alumina fiber characterized by having a ratio of 2 or more. (2) Adding colloidal silica to basic aluminum chloride solution, P, Ba, Sn, Y, Co, Sr, Cr, Zr
, add lactic acid or acetic acid with or without addition of Fe metal chloride or salt to make a spinning stock solution, concentrate this to make a fiber precursor, and spin this into a fiber precursor under an NH_3 atmosphere.
A method for producing alumina fiber, which comprises heating the fiber to 1200°C in a nitrogen atmosphere containing 1 to 10% by volume of oxygen.