JPS5812393B2 - Flame-retardant synthetic fiber fabric and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame-retardant raised fabric made of synthetic fibers used for automobile upholstery, etc., and a method for producing the same.

For example, thiourea formaldehyde resin is known as a compound that imparts a flame retardant effect to synthetic fibers.
In particular, thiourea formaldehyde resins are actually often used as flame retardants for polyamide synthetic fibers.

However, when trying to impart flame retardancy to a synthetic fiber fabric raised using a raising agent, the raising agent used in the raising process lowers the flame retardancy, and if a water repellent is used in combination to impart water repellency, The water repellent agent has the disadvantage that it reduces flame retardancy and does not exhibit sufficient water repellency.

These drawbacks can be solved to some extent by removing the raising agent by washing after the raising process and selecting an appropriate water repellent. This method could not be adopted because it had the fatal disadvantage of deteriorating the texture of the pile and significantly reducing its commercial value.

In order to eliminate the above-mentioned drawbacks, the present applicant applied a raising agent to a woven or knitted fabric made of aliphatic polyamide fibers, applied a raising agent, and then applied thiourea-formaldehyde without removing the raising agent. We proposed a treatment method for polyamide fiber products that imparts flame retardancy and water repellency by adding resin and organic fusosinated polymer water repellent (Japanese Patent Application Laid-Open No. 50-10
No. 5995).

Although this method has eliminated any problems as far as the flame retardancy of the fabric is concerned, the following new problems have arisen.

In other words, (1) during heat treatment during flame retardant processing, formaldehyde is liberated and a strong irritating odor is generated, which not only harms the environmental health of workers and workers, but also causes odor pollution to residents near the processing plant. and (2) the texture of the processed flame-retardant raised fabric is relatively rough and hard, with little flexibility, which impairs workability during cutting and sewing, and also makes the product feel unpleasant when used. That's 2 points.

The present inventors have made extensive studies to solve these problems, and have found that by using a thiourea-formaldehyde low condensate in which 1.5 moles or less of formaldehyde is condensed with respect to 1 mole of the thiourea compound, The present invention was achieved by discovering that the generation of irritating odors is reduced and the texture becomes soft.

That is, the first invention contains a flame retardant containing a raising agent and a thiourea-formaldehyde low condensate obtained by condensing 1.5 mol or less of formaldehyde per 1 mol of a thiourea compound as a main component. A second invention is a flame-retardant synthetic fiber-raised fabric, in which a fabric made of synthetic fibers is coated with a napping agent and subjected to napping, and then 1 mol of a thiourea compound is added to the fabric without removing the napping agent. A method for producing a flame-retardant synthetic fiber fabric, which comprises applying a thiourea-formaldehyde low condensate obtained by condensing 1.5 mol or less of formaldehyde to a thiourea-formaldehyde, and then heat-treating at 130'C or more. .

Examples of the synthetic fibers used in the present invention include polyamide fibers such as nylon 6, nylon 66, and nylon 6.10, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, acrylic fibers such as polyacrylonitrile, and polyolefin fibers such as polypropylene. be able to.

These fibers may be made by copolymerizing small amounts of different components, or may be made by blending small amounts of different polymers.

Even if the present invention is applied to natural or regenerated fibers such as cotton, wool, silk, rayon, acetate, etc., there is no point in applying the present invention since they do not exhibit any flame retardancy.

However, when natural or regenerated fibers are used in combination with synthetic fibers, the flame retardant effect is achieved depending on the amount of synthetic fibers contained, and therefore is within the scope of the present invention.

The raising agent is preferably a commonly used surfactant type (low-molecular or high-molecular) type that lowers the surface friction coefficient of synthetic fibers.

However, it is desirable to avoid using silicone-based smoothness improvers as much as possible because they become a hindrance to flameproofing with thiourea-formaldehyde-based resins.

If silicone leveling agents are used, they should be used in minimal amounts.

For example, Kimol N (manufactured by Ssangyong Dye Pharmaceutical Co., Ltd.) GXK-
72 (manufactured by Ipposha Yushi Kogyo Co., Ltd.) is an effective raising agent for the purpose of the present invention.

The term thiourea-formaldehyde low condensate means a product in which 1.5 moles or less of formaldehyde is condensed with 1 mole of a thiourea compound having the structure of the following general formula.

[However, R1 represents a group arbitrarily selected from hydrogen or aliphatic hydrocarbon residues having 1 to 3 carbon atoms.

] Examples of the thiourea compound include thiourea, N-monomethylthiourea, N-monoethylthiourea, N,N'-dimethylthiourea, ethylenethiourea, propylene, and thiourea.

Alkoxylated thiourea formaldehyde low condensates obtained by coexisting methyl alcohol, ethyl alcohol, etc. when formaldehyde is condensed with a thiourea compound are also included in the thiourea formaldehyde low condensates of the present invention.

The conventional process of fat flame processing using thiourea-formaldehyde resin involves applying a thiourea-formaldehyde initial condensate to a fabric, heating it to cause a crosslinking reaction, and forming a strong resin on the fabric. , for that purpose, 2 formaldehyde for 1 mole of thiourea compound.
It was necessary to condense up to 4 moles and use an initial condensate having two or more functional reactive groups.

When a thiourea-formaldehyde initial condensate, which is obtained by condensing 2 to 4 moles of formaldehyde per mole of a thiourea compound, is applied to a fabric and heat-treated, some of the methylol groups decompose without participating in the reaction. This produces formaldehyde and a strong pungent odor.

In particular, when 4 moles of formaldehyde are condensed, whether it is a tetramethylol compound or a uron ring-containing dimethylol compound, a considerable excess of formaldehyde must be present in the reaction to prevent dissociation of methylol due to the reverse reaction. As a result, the pungent odor of formaldehyde becomes even stronger.

Furthermore, since the crosslinking reaction completely turns the fabric into a resin, the fabric loses its flexibility and becomes rough and hard.

In order to prevent the formation of such formaldehyde and obtain a good texture, 1.
A thiourea-formaldehyde low condensate obtained by condensing 5 moles or less, preferably 0.75 to 1.5 moles of formaldehyde may be used.

If the number of condensed moles of form and aldehyde per mole of thiourea compound exceeds 1.5 moles, formaldehyde will be produced during heat treatment, producing a strong pungent odor and making the texture of the processed fabric rough and hard.

On the other hand, if the amount of formaldehyde is less than 0.75 mol, the durability of the treated fabric may become insufficient, so it is better to avoid it as much as possible.

The number of functional reaction groups of the thiourea formaldehyde low condensate obtained by condensing 1.5 moles or less of formaldehyde is 1.5 or less, and it does not turn into a resin by heat treatment.

Therefore, it is possible to prevent rough hardening of the fabric texture due to the resinization of the flame retardant as in the conventional method, and since the proportion of formaldehyde used is low, no irritating odor is generated during the processing process.

The thiourea formaldehyde low condensate is stored as an alkaline aqueous solution.

Neutral aqueous solutions have poor storage stability, especially at temperatures of 35°C.
If the temperature exceeds this level, it becomes cloudy or precipitates within 2 to 3 days, making it unusable.

The preferred pH range is 7.0 to 9.5, and if the alkalinity becomes too strong, the catalytic ability will decrease and the reaction will not occur even during heat treatment.

When preparing the processing fluid, an organic amine salt catalyst such as Sumitex Accelerator ACX (manufactured by Sumitomo Chemical Co., Ltd.) is usually added to the processing fluid as a catalyst for the condensation reaction of the thiourea-formaldehyde low condensate. About 10% by weight of the effective amount of the thiourea formaldehyde low condensate is added.

The amount of flame retardant mainly composed of thiourea formaldehyde low condensate applied to the fabric is 2 to 15% based on the weight of the fiber.
Preferably, it is expressed as % by weight.

In particular, it is more preferably 3 to 8% by weight.

In the present invention, thiourea is obtained by subjecting a synthetic fiber cloth treated with a raising agent to a raising treatment by a conventional method, and condensing formaldehyde in an amount of 1.5 mol or less per 1 mol of a thiourea compound while still containing the raising agent. Add a formaldehyde low condensate.

In this case, a condensation reaction catalyst is used in combination, if necessary.

To react thiourea formaldehyde low condensate 13
It is necessary to heat treat at 0°C or higher.

Examples of methods for applying a thiourea formaldehyde low condensate and a catalyst to a raised fabric made of synthetic fibers include the following method.

That is, the target raised fabric is patted with an aqueous solution containing a thiourea formaldehyde low condensate and a condensation reaction catalyst, dried at 90 to 120°C for 2 to 5 minutes, and finally dried at 130 to 170°C for 0. Process for 5-5 minutes.

The treated raised fabric thus obtained has flame retardant and flame retardant properties with moderate durability of the thiourea formaldehyde low condensate, and has a good texture without the roughness and hardness of conventional raised fabrics. be.

Further, according to the present invention, the generation of formaldehyde during heat treatment is extremely small, and irritating odor is almost eliminated, so the working environment is improved and no pollution problem occurs.

The flame-retardant synthetic fiber fabric according to the present invention can be used in a wide range of applications, including chair upholstery, furniture, and wall coverings for general passenger cars, buses, trucks, trains, airplanes, passenger ships, etc.

Next, examples of the present invention will be shown.

Note that all concentrations (weight) of processing agents used in Examples are apparent concentrations.

In addition, flame retardancy, water repellency, texture, and odor were evaluated by the following methods.

(1) Flame resistance is based on the U.S. Federal Motor Vehicle Safety Standards (MVSS30).
According to 2), both the processed fabric and the fabric soaked in water for 30 minutes (to determine durability) were evaluated.

(2) Water repellency was evaluated by the spray method of JISL1079-66.

(3) The texture was judged as hard or soft by touch.

(4) Odor was determined by the strength of formalin odor during processing.

Example 1, Comparative Example 1 Nylon 6 filament yarn (SD70de/l6fil
s) was used to knit a full-face raised tricot knitted fabric with 73 courses/inch and 45 wells/inch and a basis weight of 300 g/mm2.

Next, this knitted fabric was refined and dyed by a conventional method, and then treated with a raising agent at 40°C for 60 minutes using a solution (4 g/l) of Kimol N (raising agent manufactured by Ssangyong Dye Pharmaceutical Co., Ltd.) using a beam dyeing machine. .

After that, the brushing process was performed using a rotary napping machine, and it was putted with the processing liquid shown in the following table (squeezing ratio: 63%), and continued to 10
After drying at 0°C for 3 minutes, it was heat-treated at 160°C for 45 seconds.

The results of evaluating the performance of the treated fabric are shown in the table below.

40%.

2) A thiourea-formaldehyde initial condensate aqueous solution prepared by condensing 1 mole of thiourea with 2 moles of formaldehyde, pH 7.0, effective content 40%.

As is clear from the table, it can be seen that the processed fabric according to the present invention exhibits extremely excellent performance.

Example 2, Comparative Examples 2-3 Polyester filament yarn (SD75de/24fi
A raised knitted fabric was obtained by knitting, scouring, dyeing, treating with a raising agent, and raising the fabric in the same manner as in Example 1.

This raised knitted fabric is padded with the processing liquid shown in the table below (
After drying for 3 minutes at 100℃,
Heat treatment was performed at 60°C for 45 seconds.

The results of evaluating the performance of the treated fabric are shown in the table below.

As is clear from the table, the processed fabric according to the present invention has excellent performance.

Example 3 Polyester filament yarn (SD75de/2
4fiIs), nylon filament yarn (SD7
A raised fabric was obtained by knitting and processing in the same manner and under the same conditions as in Example 1, except that 0de/16fils) was used.

The resulting brushed fabric had excellent flame retardancy and texture, and no odor was generated during heat treatment.

Claims (1)

[Scope of Claims] 1 Contains a raising agent and a flame retardant whose main component is a thiourea-formaldehyde low condensate obtained by condensing 1.5 mol or less of formaldehyde per 1 mol of a thiourea compound. A flame-retardant synthetic fiber fabric that is characterized by: 2. The raised fabric according to claim 1, wherein the thiourea formaldehyde low condensate is obtained by condensing 0.75 to 1.5 moles of formaldehyde to 1 mole of the thiourea compound. 3. The raised fabric according to claim 1 or 2, wherein the attached amount of the flame retardant mainly composed of a thiourea formaldehyde low condensate is 2 to 15 parts by weight based on the weight of the fibers. 4 A fabric made of synthetic fibers is subjected to a napping treatment by applying a napping agent, and then 1.5 moles or less of formaldehyde is condensed with respect to 1 mole of a thiourea compound without removing the napping agent. A method for producing a flame-retardant synthetic fiber fabric, which comprises applying a thiourea-formaldehyde low condensate and then heat-treating at 130°C or higher. 5. The method according to claim 5, wherein a condensation reaction catalyst is present together with the thiourea formaldehyde low condensate.