JPS6024205B2 - Flame-retardant composite fiber and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite fiber with excellent flame retardancy and a method for producing the same. , relates to a polyolefin composite fiber and a method for producing the same.

Polyolefin composite fibers have excellent thermal adhesion, physical and chemical properties, and are lightweight and inexpensive, so they are used in a wide variety of fields as nonwoven fiber materials. For example, it is suitable as a material for thin materials such as base cloth, sanitary materials, napkins, and paper diapers, and for thick materials such as quilts, various felts, filters, fiber molded bodies, and civil engineering materials. However, textile materials used indoors are generally required to be flame retardant. The first method for making polyolefin fiber flame retardant is to add a flame retardant to a raw material polymer and then spin the fiber. However, adding a large amount of flame retardant causes problems such as yarn breakage during grade yarn, which in turn impairs the quality of the product such as a decrease in strength. In addition to the above-mentioned methods, there are also known methods such as coating the material with an elutriation agent or interfering with the key elutriation fibers, but these methods require the fibers to be processed in post-processing once they have been molded, resulting in a complicated process. There are many variations in quality, and the cost is high, making it impractical. An object of the present invention is to provide a polyolefin composite fiber with extremely good flame retardancy and a method for producing the same, which uses a scale flame agent efficiently.

The present invention has found that by mixing a flame retardant into only the low melting point component of a conjugate fiber made of a polyolefin polymer, a conjugate fiber with even better flame retardancy can be obtained than when it is mixed into the entire yarn. It was done out of the blue.

One of the present inventions is that a fiber-forming polyolefin polymer is used as a high melting point component, and the melting point is 10 times lower than that of the high melting point component.
A polyolefin-based flame-retardant composite woven fabric characterized in that a polyolefin-based polymer containing 0.5 to 5% (by weight) of a flame retardant is used as a low-melting point component, and both components are arranged in a composite structure. .

Another aspect of the present invention is that a fiber-forming polyolefin polymer is used as a high melting point component, and a polyolefin polymer having a melting point lower than that by 100 or more is used as a low melting point component to form a molten composite grade yarn. A method for producing a flame-retardant composite fiber, which comprises mixing a flame retardant with a flame retardant at a content of 0.5 to 5% (by weight) based on the low melting point component after mixing and forming a composite fiber. be. In general, composite fibers can be given various characteristics in windability and adhesiveness depending on how the two components are combined, and can be used for various purposes.

The composite fiber of the present invention has various uses, but in particular, it can be made into a parallel type or sheath-core type composite structure so that the fiber cross-sectional circumference of the low melting point component is 50% or more. It is preferable to have heat fusion properties. In this case, the composite (high melting point component: low melting point component) is 5:6 to 3:
7 is preferable in terms of the thickness of the low melting point component in the fiber cross section. As the high melting point component, polypropylene or a propylene-based copolymer having fiber-forming properties is preferred. Examples of the low melting point component include polyethylene, a chelate-vinyl acetate copolymer (sometimes abbreviated as EVA) having a vinyl acetate content of 1 to 10% (by weight), a saponified product thereof, or a combination of polyethylene and EVA or saponified polyethylene. A mixture with VA and the like are preferred. The flame retardant used in the present invention may be any known flame retardant, and these include phosphorus-based, ammonium salt-based, halogen-based compounds, and the like. Among these, organic halogen compounds are preferred, specifically perchlorobentacyclododecane, ethylenediamine dihydromide, bentabromomonochlorocyclohexane, pentabromotoluene, hexapromobenzene, 2,2bis[4-(2,3dibromopropoxy)] -3,5 dibromophenyl]propane, tris(2,3 dibromopropyl) phosphate, and the like. Also, these flame retardants and SQ03 were mixed at 1.5:1.
It is also suitable to use a mixture in a ratio of ~3:1. If the content of the flame retardant is less than 0.5% of the low melting point components, preferred flame retardancy cannot be obtained, and if it is less than 5%, the drawability becomes poor and the quality of the product is impaired, which is not preferable. The flame-retardant composite woven fabric of the present invention can be produced by a known fused composite paper yarn method, and the paper yarn apparatus used may also be of a known type.

The undrawn yarn obtained by drawing the composite paper yarn is desirably stretched to an appropriate stretching ratio of 4 times or less, for example 2 to 4 times, according to a conventional method. Since the flame retardant composite fiber of the present invention contains the flame retardant only in the low melting point component, compared to the case where the flame retardant is contained in the entire yarn, the flame retardant composite fiber has a higher temperature when using the same amount of flame retardant. It has flame retardancy, and if it has the same degree of flame retardancy, it is possible to reduce the amount of expensive flame retardant used.

Next, examples will be described, in which PP is polypropylene, PE is polyethylene, EVA is ethylene-pinyl acetate copolymer, and MFR is ASTM D-1238 (L).
The melt flow rate value and MFR ratio respectively indicate the ratio of MPR of the low melting point component to M'R of the high melting point component. Examples 1 to 3, Comparative Examples 1 to 4 Medium-low pressure PE (MFR2o) was used as a low melting point component, isotatic PP (MFR4) was used as a high melting point component, and 2,2-bis[4-2,3] was used as a scale retardant. dibromopropoxy)-3,5-dibromophenyl]propane and SQ
A predetermined amount of 03 mixed at a ratio of 2:1 was added to the composite components as shown in the table, and the composite fibers were made into a composite fiber at a composite ratio of 1:1 with 210 CO on the low melting point component side and 300 CO on the high melting point component side, A parallel type composite undrawn yarn having a fiber cross-sectional circumference of 72 to 83% was obtained as a low melting point component.

This material was stretched to 3 times its original size and then cut into a cloth of 64 threads/f (denier per filament), and after carding, it was made into a web of 250 threads/f. 1400 this web
After heat treatment for 0-5 minutes, press at a pressure of 0.5 [9/s],
A binder-free nonwoven fabric sheet having a thickness of 2 layers and having the PE side fused together was obtained. After cooling this sheet in a desiccator for 3 to 4 hours,
A combustion test was conducted using the 50-microburner method, and the afterflame time (seconds) and coal fire area (flow) were measured for each test.

The results are shown in the table. In Example 1 and Comparative Example 2, Example 2 and Comparative Example 3, and Example 3 and Comparative Example 4, the total amount of flame retardant in the fibers is the same, but in the case of Example, the elutriation was much higher than in Comparative Example. It worked.

Further, as in Comparative Example 1, when the amount of the embedding agent is less than 0.5% on the high melting point side, the embedding effect is not sufficient. From the evaluation of spinnability,
Mixing the key refueling agent only with the low melting point component as in the present invention improves the weavability compared to mixing it with the high melting point component, but
It was determined that it would be difficult to produce a mixture containing more than 5 parts of chicken fuel. Examples 4 to 5, Comparative Examples 5 to 6 EVA (MFR25) with 5% vinegar content was used as a low melting point component, isotactic PP (MFR4) was used as a high melting point component, and perchlorobentacyclododecane was used as a key refueling agent. A flame retardant prepared by mixing Sb203 and Sb203 in a ratio of 1:2 was added to the composite component as shown in the table, and the composite ratio was 1:2 at 25,000 pm on the low melting point component side and 280 pm on the high melting point component side.
The undrawn yarn obtained from the composite paper yarn in step 1 was stretched and cut four times to obtain a sheath-core composite fiber fabric (button/fx51 skin) with a low melting point component and a fiber cross-sectional circumference of 100%. Example 1~
A nonwoven fabric sheet was made from the same machine as No. 3, and the flame retardance was evaluated.

The results are shown in the table. Example 4 and Comparative Example 5, and Example 5 and Comparative Example 6 have the same total addition rate of the flame retardant in the fibers, but the Example has a considerably greater flame retardant effect than the Comparative Example.

Examples 6 to 8, Comparative Examples 7 to 9 High pressure PE (MFR, o) was used as a low melting point component, Physotactic PP (MFR6) was used as a high melting point component, and Tris (2,3 Dibromopropyl) phosphate was added to the composite components as shown in the table, and the low melting point component side was 210 qo and the high melting point component side was 300 qo at a composite ratio of 1:1.
3.3 parts of the undrawn yarn obtained by yarning the fibers were drawn and cut to form parallel composite fiber fabric (1 fence/fx64 legs) with a cross-sectional circumference of 50 to 52%. ) was obtained.

This material was made into a nonwoven fabric sheet in the same manner as in Example 193, and its flame retardance was evaluated. The results are shown in the table. Example 6 and Comparative Example 7, Example 7 and Comparative Example 8, and Example 8 and Comparative Example 9 have the same total amount of flame retardant added in the fibers, but the Example has a considerably greater flame retardant effect than the Comparative Example. .

table *Indication of spinnability ◎Thread trimming 0 ○1-2 times/hour △3-9 times/hour ×lo times or more/hour (unusable)

Claims (1)

[Scope of Claims] 1. A polyolefin polymer containing a fiber-forming polyolefin polymer as a high melting point component and containing 0.5 to 5% (by weight) of a flame retardant whose melting point is 10°C or more lower than that of the melting point component. A polyolefin-based flame-retardant composite fiber characterized by having a composite structure of both components as a low melting point component. 2 Composite ratio (high melting point component: low melting point component) is 5:5 to 3:
7, and the fiber cross-sectional circumference of the low melting point component is 50% or more. 3. The flame-retardant composite fiber according to claim 1 or 2, wherein the low melting point component is polyolefin. 4. The flame-retardant composite fiber according to claim 1 or 2, wherein the low melting point component is an ethylene-vinyl acetate copolymer. 5. The flame-retardant composite fiber according to claim 1 or 2, wherein the high melting point component is polypropylene. 6. The flame-retardant composite fiber according to claim 1 or 2, which uses an organic halogen flame retardant as a flame retardant. 7 Organic halogen flame retardant and Sb_2O_ as flame retardant
3. The flame-retardant composite fiber according to claim 1 or 2, which is used in combination with 3. 8 When performing melt composite spinning using a fiber-forming polyolefin polymer as a high melting point component and a polyolefin polymer having a melting point 10°C or more lower than that of the high melting point component as a low melting point component, a flame retardant is added only to the low melting point component. A flame-retardant composite fiber characterized in that it is mixed to a content of 0.5 to 5% (by weight) based on the low melting point components after mixing, composite-spun, and then stretched at an unstretched ratio of 4 or less. manufacturing method.