JPS597658B2 - Inorganic fiber surface treatment method - Google Patents

Description

[Detailed Description of the Invention] The present invention has a general formula of T i (OR)4 (R=
This relates to an inorganic fiber surface treatment method using organic titanium compounds represented by C4H9, C3H7, C2H5), and its purpose is to treat the surface of inorganic fibers in the production of inorganic fibers.
By coating all fibers with a film with a uniform and sufficient thickness on the fiber surface, and further modifying the film through post-treatment to protect the inorganic fibers from mechanical and chemical deterioration (particularly alkali deterioration). An object of the present invention is to provide an inorganic fiber surface treatment method that can obtain inorganic fibers that have a large initial strength protection effect.

In general, inorganic fibers such as glass wool and rock wool have extremely high tensile strength (200 to 300 kg/ma) unless there is mechanical or chemical surface damage after melt spinning.

In order to avoid this mechanical and chemical surface damage, for example, long glass fibers are uniformly coated with various resin films called sizing agents.

However, since inorganic fibers such as glass wool and rock wool are made in large quantities by the disk method or high-speed air blowing method, the surface treatment during cotton production is limited to a binder spray, which is difficult to form a uniform film on the fiber surface. It was not possible to do so, and droplets were partially attached.

For this reason, the strength of inorganic staple fibers is significantly reduced by mechanical contact after cotton-making.

In view of the above circumstances, for the purpose of forming a uniform protective film on the surface of inorganic fibers and maintaining initial strength, for example, immediately after cotton production, a surface treatment agent is sprayed in vapor form and thermally decomposed on the high temperature fiber surface. Methods of causing chemical reactions such as these are being studied, but at present, satisfactory results have not been obtained because the uniformity of the film attached to the fiber surface, especially the film thickness, is still insufficient.

Generally, inorganic short fibers such as glass wool and rock wool are produced by introducing mineral raw materials melted at a high temperature of 1,300 to 1,500 degrees Celsius onto a disk rotating at high speed, and the centrifugal force of the fibers forming the fibers from around the disk or ejecting them from a nozzle. It is blown away by high-speed airflow or flame and turned into fibers.

These fibers are sent into a collection box by the transport air current, collected on a conveyor net, conveyor belt, etc., and transported, and then processed into a board by spraying with resin, etc.
Alternatively, it can be used as a raw material for other secondary products after undergoing particle removal, defoaming, and granulation processes.

Examining the fiber strength in the above process, it is found that immediately after cotton milling, it is 200 to 300 kg/r+t, and when it is collected, it is 170 to 230 kg/r+t, and after shedding and opening, it is 400 to 300 kg/r+t.
0-100kg/rn1? It was found that the temperature had deteriorated significantly.

Most of these strength deteriorations occur due to mechanical contact between fibers, and therefore, these strength deteriorations can be prevented by forming a protective film on the fiber surface.

In the present invention, during cotton collection, inorganic fibers loosely deposited on a conveyor net (or conveyor belt) are continuously fed as they are into a surface treatment chamber.

Organic titanium compounds (Ti(OR)) are added to the inorganic fibers fed into the chamber.
5) the steam is ejected from the nozzle toward the inorganic fibers,
Furthermore, H20 vapor is simultaneously ejected from another nozzle.

A suction box is installed under the conveyor net so that the treated steam and water vapor are mixed, passed between the fibers, and exited to the conveyor net.

The reaction at this time is a hydrolysis condensation reaction, and basically, (1) progresses at a high speed. Furthermore, a complex amorphous titanium compound film is formed depending on the concentration and specific gravity of both.

Organic titanium compounds include Ti (OC2H5)4, Ti
Hydrolysis is easy in the order of (OC3H7)4 and Ti (OC4Hg)4, and although the optimum water vapor concentration for the vapor of each organic titanium compound under the processing conditions is different,
For example, steam concentration 2000 ppm, steam temperature 2
When an organic titanium compound is ejected from a nozzle at a flow rate of 50 l/min using nitrogen gas or dry air as a carrier gas at 00°C, the concentration of water vapor is 3000 ppm.
, at a temperature of 200°C and a flow rate of 5 using nitrogen gas as a carrier gas.
By ejecting from a separate nozzle at 0 l/min,
Water vapor is in excess of all the organic titanium compounds and can be sufficiently hydrolyzed and condensed.

Furthermore, depending on certain conditions, a film may not be formed on the fiber surface and only white powder may be attached.

Since the thickness of the amorphous titanium compound film formed on the fiber surface increases proportionally with the processing time, a film thickness sufficient to withstand mechanical damage can be obtained without the difficulty of (q).

If the temperature of the atmosphere is high, a film will be formed efficiently, but
The upper limit of the temperature is determined by thermal deterioration of the fibers, thermal decomposition of the processing steam, etc.

Since the above surface treatment method utilizes a hydrolytic condensation reaction, when the treatment is carried out at a low temperature, for example, 100 to 300°C, the resulting film contains alcohol (Bu
OH, PrOH), and water (H20) during condensation.

When these by-products are included in the film, the more the film contains them, the weaker the adhesion of the film to the inorganic fibers, and the lower the hardness of the film, resulting in a smaller protective effect.

Therefore, it is necessary to increase the film thickness in order to sufficiently withstand mechanical damage.

Furthermore, the higher the treatment atmosphere temperature, the fewer these by-products are in the film, and the better the protective effect is. However, for example, when the temperature of E-glass composition fibers exceeds 200° C., the fibers themselves undergo thermal deterioration, resulting in a negative effect.

Therefore, a protective effect can be obtained by increasing the film thickness by processing at a low temperature below the temperature at which thermal deterioration of the fibers occurs, that is, by using a large amount of the processing agent.

Although this treatment can provide a sufficiently large protective effect, in order to further increase this protective effect, it is necessary to reduce the amount of alcohol (BuOH, PrOH) and water (H20) in the film, and also to reduce the amount of alcohol (BuOH, PrOH) and water (H20) in the film. By increasing the adhesion and hardness, it is possible to perform a treatment that provides sufficient protection even if the thickness of the film is reduced.

That is, as described above, after forming an amorphous titanium compound film obtained by hydrolytic condensation on the fiber surface, the fiber is dried by heating or transported into a container that can reduce the pressure, and the fiber is heated to a temperature below the thermal deterioration temperature of the fiber. Temperature (e.g. 200°C for E glass composition)
By-products such as alcohol and water in the film are removed by heating and reducing the pressure.

In this case, the organic titanium compound treatment is carried out simultaneously with processing agent vapor and water vapor, but it is more effective to carry out the step of carrying out reduced pressure heat treatment after a certain period of treatment, and then continuing the simultaneous treatment.

The appropriate degree of pressure reduction is 5 to 20 mmHg.

In the present invention, as described above, Ti (OR)4 (R=C4HQ, C3H7) is added to the inorganic fiber immediately after cotton production.
, C2H,.

Organic titanium compound vapor and water vapor are simultaneously sprayed to form a film on the surface of the inorganic fibers through a hydrolytic condensation reaction, so unlike the dispersion of droplets using a spray method, because it is a gas phase process, narrow spaces between the fibers can be formed. Steam can penetrate into the voids sufficiently, and a film of titanium compound can be formed on the surface of all the fibers, not only in the case of long fibers but also in the case of short fibers, resulting in high initial strength immediately after cotton production. prevent deterioration,
It is possible to obtain inorganic fibers with high strength.

In addition, in the same gas phase treatment method, in the gas phase pyrolysis method, the treatment time is limited to a short time due to the cooling period of the inorganic fibers immediately after production, but in the present invention, the treatment time does not require high temperatures. By allowing a sufficiently long time, a sufficiently thick film with sufficient reinforcing and protective effects can be produced.

In addition, after the film is formed, by-products such as water and alcohol remaining during film formation are removed by heating and drying or heating and decompression, so that by-products such as water and alcohol mixed into the film can be removed. It prevents deterioration of adhesion, hardness, etc., and the -OH and -OR groups remaining in the film are irreversibly removed, making the film more similar to the TiO2 film, improving not only its mechanical strength, but also its mechanical strength. It is possible to obtain a large resistance against chemical deterioration such as alkali resistance, and to exhibit a sufficiently large protective effect even with a relatively thin film formed by short-time treatment.

The present invention will be specifically described below based on examples.

Example Si0240% by weight, Ca040% by weight, AI2031
A glass wool material having a glass composition of 5% by weight and 5% by weight of Mg0 is melted in an electric furnace at 1500°C, and the molten material is heated to a cotton manufacturing disk with a diameter of 200φ and a rotation speed of 3000.
The cotton is produced under the conditions of rpm and processing amount of 0.5 t/hour, and the steam and water vapor of the following processing materials are applied to the fibers loosely deposited on the conveyor net at the bottom of the cotton collection box through separate nozzles. They were sprayed at the same time so that they matched on the top surface of the band.

The fiber diameter of the collected glass coolant was 10 to 15 μφ.

The glass surface treatment time was 30 minutes, and the film thickness of the amorphous titanium compound on the fiber surface was approximately 300 minutes.

The IR absorption amount of -OH groups in the film was reduced to 1/10 by the reduced pressure heat treatment.

Furthermore, even after being left in air, the amount of --OH group absorbed did not increase.

The results of measuring the tensile strength of the glass wool subjected to the above treatment are as follows.

Furthermore, the tensile strength after treatment with cement alkali (80° C.) for 40 hours was measured and was as follows.

However, as a cement alkali, NaOH is o. s
S? /l, KOH is 3. 4 5 fl/l:,C
a(OH)2 is o. 4s? /l was used, and the intensity measurement conditions were as follows.

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Claims (1)

[Claims] 1 T i (OR) 4 for inorganic fibers immediately after cotton production
Steam of an organic titanium compound represented by (R = C4H9, C3H7, C2H5) and water vapor are simultaneously sprayed to form a film by a hydrolytic condensation reaction on the surface of the inorganic fiber, and then water, alcohol, etc. remaining in this film are removed. An inorganic fiber surface treatment method characterized by removing by-products by heat drying or reduced pressure.