JP2014094969A - Flame-retardant resin composition and cable using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant resin composition and the like which can ensure excellent flame retardancy while ensuring excellent mechanical properties.SOLUTION: A flame-retardant resin composition comprises: a base resin; calcium carbonate particles which are compounded at a ratio of 10 pts.mass or more with respect to 100 pts.mass of the base resin; a silicone-based compound which is compounded at a ratio of more than 1 pt.mass with respect to 100 pts.mass of the base resin; and a fatty acid-containing compound which is compounded at a ratio of more than 3 pts.mass with respect to 100 pts.mass of the base resin. The average particle diameter of the calcium carbonate particles is 0.7 μm or more.

Description

  The present invention relates to a flame retardant resin composition and a cable using the same.

  Polyvinyl chloride compositions are widely used in wire coatings, tubes, tapes, packaging materials, building materials, etc. because of their good electrical insulation and excellent flame retardancy and mechanical properties. Lead-free polyvinyl chloride resin that does not use lead as a stabilizer is becoming mainstream because of concerns about the effects on the human body.

  Since the lead-free polyvinyl chloride resin contains chlorine atoms in its molecular structure, it generates toxic and harmful chlorine gas during combustion. Therefore, a vinyl chloride electric wire replacement using a so-called eco-material with higher safety is being studied.

  As such an ecomaterial, a composition is known in which calcium carbonate is added as a flame retardant to a polyolefin resin, and a silicone compound such as silicone oil or magnesium stearate is added as a flame retardant aid ( See Patent Document 1 below).

JP-A-9-169918

  However, it has been difficult to say that the composition described in Patent Document 1 has sufficient flame retardancy. Here, if the amount of the flame retardant added is increased, the flame retardancy can be improved. However, in this case, the mechanical properties of the composition are deteriorated.

  For this reason, the flame-retardant resin composition which can also ensure the outstanding flame retardance, ensuring the outstanding mechanical characteristic was calculated | required.

  The present invention has been made in view of the above circumstances, and provides a flame retardant resin composition capable of ensuring excellent flame retardancy while ensuring excellent mechanical properties, and a cable using the same. With the goal.

  In order to solve the above-described problems, the present inventors have studied paying attention to calcium carbonate which is a flame retardant. As a result, it is usually necessary to increase the specific surface area of the flame retardant by reducing the average particle size of the flame retardant particles in order to ensure flame retardancy. It has been found that by setting the diameter to a specific value or more, an excellent flame retardant effect is exhibited even if the blending amount is small. Furthermore, it was also found that such an excellent flame retardant effect is exhibited when the silicone compound and the fatty acid-containing compound are blended at a specific ratio with respect to the base resin. That is, the present inventors have found that the above problems can be solved by the following invention.

  That is, the present invention comprises a base resin, calcium carbonate particles blended at a ratio of 10 parts by mass or more with respect to 100 parts by mass of the base resin, and a ratio greater than 1 part by mass with respect to 100 parts by mass of the base resin. A flame retardant in which the average particle size of the calcium carbonate particles is 0.7 μm or more, and a fatty acid-containing compound that is blended in a proportion greater than 3 parts by mass with respect to 100 parts by mass of the base resin. It is an adhesive resin composition.

  According to the flame retardant resin composition of the present invention, the average particle diameter of the calcium carbonate particles is 0.7 μm or more, so that the calcium carbonate particles are effectively flame retardant even if the blending amount of the calcium carbonate particles is small. Therefore, it is possible to ensure excellent flame retardancy while ensuring excellent mechanical properties.

  In addition, the present inventors speculate as follows about the reason why more excellent flame retardancy is obtained in the flame retardant resin composition of the present invention.

  That is, a surface barrier layer is formed at the time of combustion by using calcium carbonate particles, a silicone compound, and a fatty acid-containing compound. At this time, if the surface barrier layer is dense and such a dense surface barrier layer is quickly formed, it is considered that the flame retardant effect is enhanced. In order for the dense surface barrier layer to be formed quickly, it is necessary to close the gaps between the particles of calcium carbonate or decomposition products constituting the surface barrier layer as quickly as possible. In that respect, when the average particle diameter of the calcium carbonate particles is as large as 0.7 μm or more as in the present invention, the specific surface area is reduced, so that the gaps between the calcium carbonate particles can be quickly closed. As a result, it is considered that the formation speed of the dense surface barrier layer is increased and the flame retardant effect is enhanced.

  In the said flame-retardant resin composition, it is preferable that the average particle diameter of the said calcium carbonate particle is 1.2 micrometers or more.

  In this case, more excellent flame retardancy can be obtained as compared with the case where the average particle diameter of the calcium carbonate particles is less than 1.2 μm.

  In the flame retardant resin composition, the calcium carbonate particles preferably have an average particle size of 1.2 μm or more and 1.8 μm or less.

  In this case, the surface of the sheath can be made less likely to be damaged than when the average particle diameter of the calcium carbonate particles exceeds 1.8 μm.

  In the said flame-retardant resin composition, the said silicone type compound is mix | blended in the ratio of larger than 3 mass parts and 10 mass parts or less with respect to 100 mass parts of said base resins, and the said fatty acid containing compound is said base resin 100 masses. It is preferable that 5 parts by mass or more and 20 parts by mass or less are blended with respect to parts.

  In this case, compared with the case where a silicone type compound and a fatty-acid containing compound remove | deviate from the said range, the more outstanding flame retardance will be acquired or bloom will become difficult to generate | occur | produce.

  In the said flame-retardant resin composition, it is preferable that the said calcium carbonate particle is mix | blended in the ratio of 10 to 120 mass parts with respect to 100 mass parts of said base resins.

  When the proportion of the calcium carbonate particles is 120 parts by mass or less, the mechanical properties are further improved as compared with a case where the ratio is larger than 120 parts by mass.

  In the said flame-retardant resin composition, it is preferable that the said calcium carbonate particle is mix | blended in the ratio of 10 to 80 mass parts with respect to 100 mass parts of said base resins.

  In the said flame-retardant resin composition, it is preferable that the said calcium carbonate particle is mix | blended in the ratio of 10 to 50 mass parts with respect to 100 mass parts of said base resins.

  In the said flame-retardant resin composition, it is preferable that the said calcium carbonate particle is mix | blended in the ratio of 10 to 30 mass parts with respect to 100 mass parts of said base resins.

  In the said flame-retardant resin composition, it is preferable that the said calcium carbonate particle is mix | blended in the ratio of 10 to 20 mass parts with respect to 100 mass parts of said base resins.

  When the calcium carbonate particles are blended in the above ranges, the mechanical properties are further improved while sufficiently ensuring the flame retardancy of the flame retardant resin composition, compared to the case where the upper limit value of each range is exceeded. Can do.

  In the flame retardant resin composition, the base resin is preferably a polyolefin compound, for example.

  In the flame retardant resin composition, the silicone compound is preferably a silicone gum.

  In this case, bloom is less likely to occur.

  In the flame retardant resin composition, the fatty acid-containing compound is preferably magnesium stearate. In this case, more excellent flame retardancy can be obtained as compared with the case where the fatty acid-containing compound is not magnesium stearate.

  In the flame retardant resin composition, the fatty acid-containing compound may be stearic acid.

  Moreover, this invention is equipped with the insulated wire which has a conductor and the insulating layer which coat | covers the said conductor, and the said insulating layer is a cable comprised with the flame-retardant resin composition mentioned above.

  The present invention further includes a cable having a conductor, an insulating layer covering the conductor, and a sheath covering the insulating layer, wherein at least one of the insulating layer and the sheath is the above-described flame retardant resin composition. It is a cable composed of

In the present invention, the “average particle size” means that the area S of the two-dimensional image when a plurality of calcium carbonate particles are observed with an SEM is obtained, and these areas S are considered to be equal to the area of a circle, respectively. From these areas, the following formula:
R = 2 × (S / π) ^1/2
The average value of R calculated based on

  ADVANTAGE OF THE INVENTION According to this invention, the flame retardant resin composition which can ensure the outstanding flame retardance while ensuring the outstanding mechanical characteristic, and a cable using the same are provided.

It is a partial side view which shows one Embodiment of the cable of this invention. It is sectional drawing along the II-II line of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2.

[cable]
FIG. 1 is a partial side view showing an embodiment of a cable according to the present invention, and shows a flat cable. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. As shown in FIGS. 1 and 2, the flat cable 10 includes two insulated wires 4 and a sheath 3 that covers the two insulated wires 4. The insulated wire 4 includes an inner conductor 1 and an insulating layer 2 that covers the inner conductor 1.

  Here, the insulating layer 2 is comprised with the flame-retardant resin composition, and this flame-retardant resin composition is mix | blended in the ratio of 10 mass parts or more with respect to 100 mass parts of base resins. Calcium carbonate particles, a silicone compound blended in a proportion greater than 1 part by weight with respect to 100 parts by weight of the base resin, and a fatty acid-containing compound blended in a proportion greater than 3 parts by weight with respect to 100 parts by weight of the base resin Is included. Here, the average particle diameter of the calcium carbonate particles is 0.7 μm or more.

[Cable manufacturing method]
Next, the manufacturing method of the flat cable 10 mentioned above is demonstrated.

(conductor)
First, the inner conductor 1 is prepared. The inner conductor 1 may be composed of only one strand, or may be configured by bundling a plurality of strands. Further, the inner conductor 1 is not particularly limited with respect to the conductor diameter, the material of the conductor, and the like, and can be appropriately determined according to the application.

(Flame retardant resin composition)
On the other hand, the flame retardant resin composition is prepared. As described above, the flame retardant resin composition is 1 mass per 100 parts by mass of the base resin, calcium carbonate particles blended at a ratio of 10 parts by mass or more with respect to 100 parts by mass of the base resin. It contains a silicone compound blended at a ratio greater than 3 parts by weight and a fatty acid-containing compound blended at a ratio greater than 3 parts by weight with respect to 100 parts by weight of the base resin.

(Base resin)
The base resin is not particularly limited as long as it is a resin, and examples of such a resin include polyolefin compounds such as polyethylene and polypropylene.

(Calcium carbonate particles)
The calcium carbonate particles may be either heavy calcium carbonate or light calcium carbonate.

  The average particle diameter of the calcium carbonate particles is 0.7 μm or more. When the average particle size of the calcium carbonate particles is less than 0.7 μm, the flame retardancy is remarkably lowered.

  The average particle diameter of the calcium carbonate particles is preferably 1.2 μm or more. In this case, more excellent flame retardancy can be obtained as compared with the case where the average particle diameter of the calcium carbonate particles is less than 1.2 μm.

  However, the average particle size of the calcium carbonate particles is preferably 1.8 μm or less. In this case, the surface of the sheath can be made less likely to be damaged than when the average particle diameter of the calcium carbonate particles exceeds 1.8 μm.

  The calcium carbonate particles may be blended at a ratio of 10 parts by mass or more with respect to 100 parts by mass of the base resin. When the calcium carbonate particles are blended at a ratio of less than 10 parts by mass with respect to 100 parts by mass of the base resin, the flame retardancy is significantly reduced.

  The calcium carbonate particles are preferably contained at a ratio of 120 parts by mass or less with respect to 100 parts by mass of the base resin. When the ratio of the calcium carbonate particles is 120 parts by mass or less, the mechanical properties can be further improved while sufficiently ensuring the flame retardancy of the flame retardant resin composition, compared to a case where the proportion is greater than 120 parts by mass.

  The calcium carbonate particles are more preferably contained in a proportion of 80 parts by mass or less, more preferably in a proportion of 50 parts by mass or less, and in a proportion of 30 parts by mass or less. Is still more preferred, and it is particularly preferred that it is contained in a proportion of 20 parts by mass or less. When the calcium carbonate particles are blended in the above ranges, the mechanical properties are sufficiently improved while sufficiently ensuring the flame retardancy of the flame retardant resin composition, compared to the case where the upper limit of each range is exceeded. Can be made.

(Silicone compound)
The silicone-based compound functions as a flame retardant aid, and examples thereof include polyorganosiloxane. Here, the polyorganosiloxane has a siloxane bond as a main chain and an organic group in a side chain. Examples of the organic group include a methyl group, a vinyl group, an ethyl group, a propyl group, and a phenyl group. Specific examples of the polyorganosiloxane include dimethylpolysiloxane, methylethylpolysiloxane, methyloctylpolysiloxane, methylvinylpolysiloxane, methylphenylpolysiloxane, and methyl (3,3,3-trifluoropropyl) polysiloxane. Is mentioned. Examples of the polyorganosiloxane include silicone powder, silicone gum, and silicone resin. Among these, silicone gum is preferable. In this case, bloom is less likely to occur.

  As described above, the silicone compound may be blended in a proportion larger than 1 part by mass with respect to 100 parts by mass of the base resin. If the silicone compound is contained at a ratio of 1 part by mass or less, the flame retardancy is lowered.

  It is preferable that the silicone compound is contained in a proportion larger than 3 parts by mass with respect to 100 parts by mass of the base resin. In this case, more excellent flame retardancy can be obtained as compared with the case where the proportion of the silicone compound is 3 parts by mass or less.

  Moreover, it is preferable that a silicone type compound is contained in the ratio of 10 mass parts or less with respect to 100 mass parts of base resins. When the proportion of the silicone compound is contained at a ratio of 10 parts by mass or less, the bloom is less likely to occur than when it is contained at a ratio greater than 10 parts by mass.

  The silicone compound may be attached in advance to the surface of the calcium carbonate particles. In this case, it is preferable that the entire calcium carbonate particles contained in the flame retardant resin composition are coated with a silicone compound. In this case, since the calcium carbonate particles can be easily dispersed in the base resin, the uniformity of characteristics in the flame retardant resin composition is further improved.

  As a method for adhering a silicone compound to the surface of calcium carbonate, for example, a silicone compound is added to and mixed with calcium carbonate particles to obtain a mixture, and then the mixture is dried at 40 to 75 ° C. for 10 to 40 minutes. The dried mixture can be obtained by pulverizing with a Henschel mixer, an atomizer or the like.

(Fatty acid-containing compound)
The fatty acid-containing compound functions as a flame retardant aid. The fatty acid-containing compound refers to a compound containing a fatty acid or a metal salt thereof. Here, as the fatty acid, for example, a fatty acid having 12 to 28 carbon atoms is used. Examples of such fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, tuberculostearic acid, oleic acid, linoleic acid, arachidonic acid, behenic acid and montanic acid. Among these, as the fatty acid, stearic acid or tuberculostearic acid is preferable, and stearic acid is particularly preferable. In this case, more excellent flame retardancy can be obtained as compared with the case of using a fatty acid other than stearic acid or tuberculostearic acid.

  Examples of the metal constituting the fatty acid metal salt include magnesium, calcium, zinc and lead. As the fatty acid metal salt, magnesium stearate is preferred. In this case, more excellent flame retardancy can be obtained as compared with the case of using a fatty acid metal salt other than magnesium stearate.

  As described above, the fatty acid-containing compound may be blended in a proportion larger than 3 parts by mass with respect to 100 parts by mass of the base resin. If the fatty acid-containing compound is contained in a proportion of 3 parts by mass or less, flame retardancy is reduced.

  Moreover, it is preferable that the fatty acid containing compound is contained in a proportion of 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the base resin. When the proportion of the fatty acid-containing compound is within the above range, more excellent flame retardancy can be obtained or bloom is less likely to occur than when the ratio is outside the above range.

  The flame retardant resin composition may further contain a filler such as an antioxidant, an ultraviolet deterioration inhibitor, a processing aid, a color pigment, a lubricant, and carbon black as necessary.

  The flame retardant resin composition can be obtained by kneading a base resin, calcium carbonate, a silicone-based compound, a fatty acid-containing compound, and the like. The kneading can be performed with a kneading machine such as a Banbury mixer, a tumbler, a pressure kneader, a kneading extruder, a twin screw extruder, a mixing roll, and the like. At this time, from the viewpoint of improving the dispersibility of the silicone compound, a part of the base resin and the silicone compound are kneaded, and the obtained master batch (MB) is mixed with the remaining base resin, calcium carbonate particles and fatty acid. You may knead | mix with a containing compound etc.

  Next, the inner conductor 1 is covered with the flame retardant resin composition. Specifically, the flame retardant resin composition is melt kneaded using an extruder to form a tubular extrudate. Then, the tubular extrudate is continuously coated on the inner conductor 1. Thus, the insulated wire 4 is obtained.

(sheath)
Finally, two insulated wires 4 obtained as described above are prepared, and these insulated wires 4 are covered with a sheath 3 produced using the above-mentioned flame-retardant resin composition. The sheath 3 protects the insulating layer 2 from physical or chemical damage.

  The flat cable 10 is obtained as described above.

  The present invention is not limited to the above embodiment. For example, although the flat cable 10 has two insulated wires 4 in the above embodiment, the cable of the present invention is not limited to the flat cable, and only one insulated wire 4 is provided inside the sheath 3. You may have, and you may have three or more. A resin portion made of polypropylene or the like may be provided between the sheath 3 and the insulated wire 4.

  Moreover, in the said embodiment, although the insulating layer 2 and the sheath 3 of the insulated wire 4 are comprised with said flame-retardant resin composition, the insulating layer 2 is comprised with normal insulating resin, and only the sheath 3 is insulated. The layer 2 may be composed of a flame retardant resin composition.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples.

(Examples 1-36 and Comparative Examples 1-13)
Polyethylene (PE), silicone masterbatch (silicone MB), fatty acid-containing compound and calcium carbonate particles are blended in the blending amounts shown in Tables 1 to 8, and kneaded at 160 ° C. for 15 minutes with a Banbury mixer, flame retardant resin A composition was obtained. In Tables 1 to 8, the unit of the blending amount of each blending component is part by mass. Moreover, in Tables 1-8, although the compounding quantity of PE is not 100 mass parts, PE is also contained in silicone MB, and if PE and PE in silicone MB are totaled, it will be 100 mass parts. .

Specific examples of the polyethylene, silicone MB, calcium carbonate particles, fatty acid-containing compound, and n-octadecane as hydrocarbons were as follows.
(1) Polyethylene (PE)
Excellen GMH GH030 (trade name, manufactured by Sumitomo Chemical Co., Ltd.)
(2) Silicone MB
X-22-2125H (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.)
Contains 50% silicone gum and 50% PE by weight (3) Calcium carbonate particles A) Calcium carbonate particles (average particle size 0.08 μm)
Shiraka Hana CCR (trade name, manufactured by Shiraishi Calcium)
B) Calcium carbonate particles (average particle size 0.15μm)
Vigot 10 (trade name, manufactured by Shiraishi Calcium)
C) Calcium carbonate particles (average particle size 0.30μm)
TunexE (trade name, manufactured by Shiraishi Calcium)
D) Calcium carbonate particles (average particle size 0.70μm)
Softon 3200 (trade name, manufactured by Shiraishi Calcium)
E) Calcium carbonate particles (average particle size 1.0μm)
NCC P-2300 (trade name, manufactured by Nitto Flour Chemical Co., Ltd.)
F) Calcium carbonate particles (average particle size 1.2μm)
NCC P-1000 (trade name, manufactured by Nitto Powder Chemical Co., Ltd.)
G) Calcium carbonate particles (average particle size 1.5μm)
Softon 1500 (trade name, manufactured by Shiraishi Calcium)
H) Calcium carbonate particles (average particle size 1.7μm)
NCC-P (trade name, manufactured by Nitto Flour Chemical Co., Ltd.)
I) Calcium carbonate particles (average particle size 1.8μm)
Softon 1200 (trade name, manufactured by Shiraishi Calcium)
J) Calcium carbonate particles (average particle size 2.2μm)
Softon 1000 (trade name, manufactured by Shiraishi Calcium)
K) Calcium carbonate particles (average particle size 3.6μm)
BF100 (trade name, manufactured by Shiraishi Calcium Co., Ltd.)
L) Calcium carbonate particles (average particle size 8.0μm)
BF300 (trade name, manufactured by Shiraishi Calcium)
M) Calcium carbonate particles (average particle size 14.8μm)
NN # 200 (trade name, manufactured by Nitto Powder Chemical Co., Ltd.)
(4) Fatty acid-containing compound A) Mg stearate
Fcochem MGS (trade name, manufactured by ADEKA)
B) Stearic acid sakura (trade name, manufactured by NOF Corporation)
C) Lauric acid NAA-122 (trade name, manufactured by NOF Corporation)
D) Behenic acid NAA-222S (trade name, manufactured by NOF Corporation)
E) Montanic acid lycowax S (trade name, manufactured by Clariant Japan)
(5) n-octadecane octadecane (trade name, manufactured by Pure Chemical Industries)

Next, this flame retardant resin composition was kneaded at 160 ° C. for 15 minutes by a Banbury mixer. Thereafter, the flame retardant resin composition is put into a single screw extruder (L / D = 20, screw shape: full flight screw, manufactured by Mars Seiki Co., Ltd.), and a tubular extrudate is extruded from the extruder. A conductor (number of strands / cross-sectional area of 2 mm ² ) was coated to a thickness of 0.7 mm. Thus, an insulated wire was obtained.

  About the insulated wire of Examples 1-36 and Comparative Examples 1-13 obtained as mentioned above, mechanical characteristics and flame retardance were evaluated as follows.

<Mechanical properties>
The mechanical properties were evaluated based on the measured tensile strength of the insulated wires of Examples 1 to 36 and Comparative Examples 1 to 13 by performing a tensile test according to JIS standard C3005. The results are shown in Tables 1-8. In Tables 1-8, the unit of tensile strength was MPa, and the pass / fail criteria for tensile strength were as follows. In the tensile test, the tensile speed was 200 mm / min, and the distance between the marked lines was 20 mm.

10 MPa or more: pass less than 10 MPa: fail

<Flame retardance>
(60 degree inclined combustion test)
About the insulated wire of Examples 1-36 and Comparative Examples 1-13, the 60 degree inclination combustion test of JISK3005 was done and the flame retardance was evaluated. The results are shown in Tables 1-8. In Tables 1 to 8, for each example and comparative example, 10 insulated wires are prepared and a flame retardancy test is performed, and an average value of the fire extinguishing time (unit: seconds) of 10 insulated wires is measured. did. Here, the fire extinguishing time is the time from self-extinguishing immediately after the end of flame contact (immediately after releasing the burner flame from the electric wire), and the shorter the fire extinguishing time, the higher the flame retardancy. At this time, the flame contact was performed until ignition of the electric wire occurred within 30 seconds. The results are shown in Tables 1-8. In Tables 1 to 8, the unit of the average value of the fire extinguishing time is seconds, and the acceptance criteria for the average value of the fire extinguishing time are as follows. In Tables 7 and 8, the comparative example that did not self-extinguish was indicated as “whole burning”.

60 seconds or less: Pass over 60 seconds: Fail

(Vertical combustion test)
About the insulated wire of Examples 5-18 and Examples 28-36, the vertical combustion test was done based on JISC3665, and the flame retardance was evaluated. The results are shown in Tables 2-4 and 6. In this case, specifically, if the length from the lower end of the upper support material that supports the insulated wire at the upper portion to the end point of carbonization is within 50 mm to 540 mm, it is indicated by “A” rank, and less than 50 mm or 540 mm In the case of super, it is indicated by “B” rank. Furthermore, for the examples indicated by “A” rank, the fire extinguishing time (unit: “A” in the items of “Flame retardance (vertical combustion test)” in Tables 2 to 4 and 6 for reference. : Seconds). Here, the fire extinguishing time is the time from immediately after the end of flame contact (immediately after separating the burner flame from the electric wire) to self-extinguishing, and the shorter the fire extinguishing time, the higher the flame retardancy. At this time, the flame contact was performed until ignition of the electric wire occurred within 60 seconds. For example, a fire extinguishing time of 0 seconds means a state in which after flame contact for 60 seconds, there is no after flame immediately after releasing the burner. In addition, the examples indicated by the rank “B” do not self-extinguish, and in Tables 2 to 4 and 6, in the item “Flame retardance (vertical combustion test)”, Is displayed. In addition, the vertical flame retardant test was not performed about Examples 1-4 and Examples 18-22. Moreover, about all the insulated wires of Comparative Examples 1-13, since the flame retardance was disqualified by the 60 degree inclination combustion test, it did not perform about the vertical combustion test.

  From the results shown in Tables 1 to 8, the insulated wires of Examples 1 to 36 reached the acceptance criteria for the mechanical properties and the 60-degree inclined combustion test. On the other hand, the insulated wires of Comparative Examples 1 to 13 did not reach the acceptance criteria for the 60-degree inclined combustion test.

  From this, it was confirmed that according to the flame retardant resin composition of the present invention, excellent flame retardancy can be secured while securing excellent mechanical properties.

DESCRIPTION OF SYMBOLS 1 ... Inner conductor 2 ... Insulating layer 3 ... Sheath 4 ... Insulated electric wire 10 ... Flat cable

That is, the present invention comprises a base resin, calcium carbonate particles blended at a ratio of 10 parts by mass to 120 parts by mass with respect to 100 parts by mass of the base resin, and 1 part by mass with respect to 100 parts by mass of the base resin. and the silicone-based compound is blended in an amount large rather than 10 parts by mass of, and a fatty acid-containing compound mixed in a proportion of less than the base resin 20 parts by weight rather greater than 3 parts by mass with respect to 100 parts by weight, the The average particle size of the calcium carbonate particles is 0.7 to 14.8 μm , and the flame retardant resin composition in which the base resin is a polyolefin compound .

In the flame retardant resin composition, the calcium carbonate particles preferably have an average particle size of 1.2 μm or more and 1.8 μm or less.

In this case, more excellent flame retardancy can be obtained as compared with the case where the average particle diameter of the calcium carbonate particles is less than 1.2 μm. Further, in this case, the surface of the sheath can be made less likely to be damaged than when the average particle size of the calcium carbonate particles exceeds 1.8 μm.

In the said flame-retardant resin composition, it is preferable that the said silicone type compound is mix | blended in the ratio of 5 mass parts or less with respect to 100 mass parts of said base resins . Moreover, it is preferable that the said fatty acid containing compound is mix | blended in the ratio of 10 mass parts or less with respect to 100 mass parts of said base resins.

In the flame retardant resin composition, the calcium carbonate particles are, for example, heavy calcium carbonate or light calcium carbonate.

<Flame retardance>
(60 degree inclined combustion test)
The insulated wire of Example 1 to 36 and Comparative Examples 1 to 13, for 60 degree inclined flame test of JIS C 3005, were evaluated the flame retardancy. The results are shown in Tables 1-8. In Tables 1 to 8, for each example and comparative example, 10 insulated wires are prepared and a flame retardancy test is performed, and an average value of the fire extinguishing time (unit: seconds) of 10 insulated wires is measured. did. Here, the fire extinguishing time is the time from self-extinguishing immediately after the end of flame contact (immediately after releasing the burner flame from the electric wire), and the shorter the fire extinguishing time, the higher the flame retardancy. At this time, the flame contact was performed until ignition of the electric wire occurred within 30 seconds. The results are shown in Tables 1-8. In Tables 1 to 8, the unit of the average value of the fire extinguishing time is seconds, and the acceptance criteria for the average value of the fire extinguishing time are as follows. In Tables 7 and 8, the comparative example that did not self-extinguish was indicated as “whole burning”.

60 seconds or less: Pass over 60 seconds: Fail

That is, the present invention comprises a base resin, calcium carbonate particles blended at a ratio of 10 parts by mass to 120 parts by mass with respect to 100 parts by mass of the base resin, and 1 part by mass with respect to 100 parts by mass of the base resin. Including a silicone compound compounded at a ratio of 10 parts by mass or less and a fatty acid-containing compound compounded at a ratio of more than 3 parts by mass and 20 parts by mass or less with respect to 100 parts by mass of the base resin, The average particle size of the particles is 1.2 μm or more and 1.8 μm or less , and the flame retardant resin composition in which the base resin is a polyolefin compound.

According to the flame retardant resin composition of the present invention, by setting the average particle diameter of the calcium carbonate particles to 1.2 μm or more, the calcium carbonate particles are effectively flame retardant even if the blending amount of the calcium carbonate particles is small. Since the effect can be exhibited, excellent flame retardancy can be ensured while ensuring excellent mechanical properties.

That is, a surface barrier layer is formed at the time of combustion by using calcium carbonate particles, a silicone compound, and a fatty acid-containing compound. At this time, if the surface barrier layer is dense and such a dense surface barrier layer is quickly formed, it is considered that the flame retardant effect is enhanced. In order for the dense surface barrier layer to be formed quickly, it is necessary to close the gaps between the particles of calcium carbonate or decomposition products constituting the surface barrier layer as quickly as possible. In that respect, when the average particle diameter of the calcium carbonate particles is as large as 1.2 μm or more as in the present invention, the specific surface area decreases, so that the gap between the calcium carbonate particles can be quickly closed. As a result, it is considered that the formation speed of the dense surface barrier layer is increased and the flame retardant effect is enhanced. Moreover, according to the flame retardant resin composition of the present invention, the surface of the sheath can be made less likely to be damaged than when the average particle size of the calcium carbonate particles exceeds 1.8 μm.

(Examples 1 to 24, Reference Examples 1 to 12 and Comparative Examples 1 to 13)
Polyethylene (PE), silicone masterbatch (silicone MB), fatty acid-containing compound and calcium carbonate particles are blended in the blending amounts shown in Tables 1 to 8, and kneaded at 160 ° C. for 15 minutes with a Banbury mixer, flame retardant resin A composition was obtained. In Tables 1 to 8, the unit of the blending amount of each blending component is part by mass. Moreover, in Tables 1-8, although the compounding quantity of PE is not 100 mass parts, PE is also contained in silicone MB, and if PE and PE in silicone MB are totaled, it will be 100 mass parts. .

Next, this flame retardant resin composition was kneaded at 160 ° C. for 15 minutes by a Banbury mixer. Thereafter, the flame retardant resin composition is put into a single screw extruder (L / D = 20, screw shape: full flight screw, manufactured by Mars Seiki Co., Ltd.), and a tubular extrudate is extruded from the extruder. A conductor (number of strands / cross-sectional area of 2 mm ² ) was coated to a thickness of 0.7 mm. Thus, an insulated wire was obtained.

About the insulated wire of Examples 1-24 obtained as mentioned above , Reference Examples 1-12, and Comparative Examples 1-13, mechanical characteristics and a flame retardance were evaluated as follows.

<Mechanical properties>
The mechanical properties were evaluated based on the measured tensile strengths of the insulated wires of Examples 1 to 24, Reference Examples 1 to 12, and Comparative Examples 1 to 13, which were subjected to a tensile test according to JIS standard C3005. The results are shown in Tables 1-8. In Tables 1-8, the unit of tensile strength was MPa, and the pass / fail criteria for tensile strength were as follows. In the tensile test, the tensile speed was 200 mm / min, and the distance between the marked lines was 20 mm.

10 MPa or more: pass less than 10 MPa: fail

<Flame retardance>
(60 degree inclined combustion test)
About the insulated wire of Examples 1-24, Reference Examples 1-12, and Comparative Examples 1-13, the 60 degree inclination combustion test of JISC3005 was done and the flame retardance was evaluated. The results are shown in Tables 1-8. In Tables 1 to 8, for each example and comparative example, 10 insulated wires are prepared and a flame retardancy test is performed, and an average value of the fire extinguishing time (unit: seconds) of 10 insulated wires is measured. did. Here, the fire extinguishing time is the time from self-extinguishing immediately after the end of flame contact (immediately after releasing the burner flame from the electric wire), and the shorter the fire extinguishing time, the higher the flame retardancy. At this time, the flame contact was performed until ignition of the electric wire occurred within 30 seconds. The results are shown in Tables 1-8. In Tables 1 to 8, the unit of the average value of the fire extinguishing time is seconds, and the acceptance criteria for the average value of the fire extinguishing time are as follows. In Tables 7 and 8, the comparative example that did not self-extinguish was indicated as “whole burning”.

60 seconds or less: Pass over 60 seconds: Fail

(Vertical combustion test)
About the insulated wire of Examples 5-18, Reference Examples 7-8, Examples 22-24, and Reference Examples 8-12, the vertical combustion test was done based on JIS C3665, and the flame retardance was evaluated. The results are shown in Tables 2-4 and 6. In this case, specifically, if the length from the lower end of the upper support material that supports the insulated wire at the upper portion to the end point of carbonization is within 50 mm to 540 mm, it is indicated by “A” rank, and less than 50 mm or 540 mm In the case of super, it is indicated by “B” rank. Furthermore, for the examples indicated by “A” rank, the fire extinguishing time (unit: “A” in the items of “Flame retardance (vertical combustion test)” in Tables 2 to 4 and 6 for reference. : Seconds). Here, the fire extinguishing time is the time from immediately after the end of flame contact (immediately after separating the burner flame from the electric wire) to self-extinguishing, and the shorter the fire extinguishing time, the higher the flame retardancy. At this time, the flame contact was performed until ignition of the electric wire occurred within 60 seconds. For example, a fire extinguishing time of 0 seconds means a state in which after flame contact for 60 seconds, there is no after flame immediately after releasing the burner. In addition, the examples indicated by the rank “B” do not self-extinguish, and in Tables 2 to 4 and 6, in the item “Flame retardance (vertical combustion test)”, Is displayed. In addition, the vertical flame retardant test was not performed about Examples 1-4 , Example 18 , Reference Examples 1-2, Examples 19-21, and Reference Examples 3-6 . Moreover, about all the insulated wires of Comparative Examples 1-13, since the flame retardance was disqualified by the 60 degree inclination combustion test, it did not perform about the vertical combustion test.

From the results shown in Tables 1 to 8, the insulated wires of Examples 1 to 24 and Reference Examples 1 to 12 reached the acceptance criteria for the mechanical properties and the 60-degree inclined combustion test. On the other hand, the insulated wires of Comparative Examples 1 to 13 did not reach the acceptance criteria for the 60-degree inclined combustion test.

Claims (15)

A base resin;
Calcium carbonate particles blended at a ratio of 10 parts by mass or more with respect to 100 parts by mass of the base resin;
A silicone compound blended in a proportion greater than 1 part by weight with respect to 100 parts by weight of the base resin;
A fatty acid-containing compound that is blended in a proportion greater than 3 parts by mass with respect to 100 parts by mass of the base resin,
A flame retardant resin composition, wherein the calcium carbonate particles have an average particle size of 0.7 μm or more. The flame retardant resin composition according to claim 1, wherein the calcium carbonate particles have an average particle size of 1.2 μm or more.   The flame retardant resin composition according to claim 2, wherein the calcium carbonate particles have an average particle size of 1.2 μm or more and 1.8 μm or less. The silicone compound is blended in a proportion of greater than 3 parts by weight and less than 10 parts by weight with respect to 100 parts by weight of the base resin.
The flame-retardant resin composition according to any one of claims 1 to 3, wherein the fatty acid-containing compound is blended at a ratio of 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame-retardant resin composition according to claim 4, wherein the calcium carbonate particles are blended at a ratio of 10 parts by mass or more and 120 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame-retardant resin composition according to claim 5, wherein the calcium carbonate particles are blended at a ratio of 10 parts by mass or more and 80 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame retardant resin composition according to claim 6, wherein the calcium carbonate particles are blended at a ratio of 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame retardant resin composition according to claim 7, wherein the calcium carbonate particles are blended at a ratio of 10 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame retardant resin composition according to claim 8, wherein the calcium carbonate particles are blended at a ratio of 10 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the base resin.   The flame retardant resin composition according to any one of claims 1 to 9, wherein the base resin is a polyolefin compound.   The flame retardant resin composition according to any one of claims 1 to 10, wherein the silicone compound is silicone gum.   The flame retardant resin composition according to any one of claims 1 to 11, wherein the fatty acid-containing compound is magnesium stearate.   The flame retardant resin composition according to any one of claims 1 to 11, wherein the fatty acid-containing compound is stearic acid. Conductors,
An insulated wire having an insulating layer covering the conductor;
The cable with which the said insulating layer is comprised with the flame-retardant resin composition as described in any one of Claims 1-13. Conductors,
An insulating layer covering the conductor;
A cable having a sheath covering the insulating layer;
A cable in which at least one of the insulating layer and the sheath is composed of the flame-retardant resin composition according to any one of claims 1 to 13.

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