KR102206643B1 - CMP grade UTP cable - Google Patents

Abstract

The present invention relates to a Plenum-grade UTP (Unshielded Twisted Pair) cable, and has high flame retardancy of a CMP (Communication Plenum) grade, does not increase thickness and volume, reduces manufacturing cost, and relates to a UTP cable made of an eco-friendly material. will be.

Description

CMP flame retardant grade UTP cable{CMP grade UTP cable}

The present invention relates to a Plenum-grade UTP (Unshielded Twisted Pair) cable, and has high flame retardancy of a CMP (Communication Plenum) grade, does not increase thickness and volume, reduces manufacturing cost, and relates to a UTP cable made of an eco-friendly material. will be.

UTP (Unshielded Twisted Pair) cable is a kind of signal line that connects the environment of a general telephone line or LAN. A plastic jacket is used to wrap the outside of a plurality of pair units made by twisting two insulated copper wires together. It is a name that means good.

FIG. 1 schematically shows a cross-sectional structure of a 4-pair UTP cable in which four pair units are wrapped with an outer jacket.

As shown in Fig. 1, the 4-pair UTP cable has a structure in which four pair units 100 are wrapped by one outer jacket 300. Here, each pair unit 100 is formed by twisting two conductive metal wires 111, preferably two conductive wires 110 insulated with an annealed copper wire, insulated with an insulator 112 at a predetermined pitch. .

In the conventional 4-pair UTP cable, in order to exhibit CMP-class flame retardancy, the insulator 112 is a fluororesin such as polytetrafluoroethylene (PTFE) resin, fluorinated ethylene propylene (FEP) resin, flame retardant polyethylene ( It is made of flame-retardant materials such as flame-retardant polyolefins such as Fire-resistant Polyethylene (FRPE) and Fire-resistant Polypropylene (FRPP).

However, fluororesin has excellent flame retardancy and electrical properties, but its high price increases the cost of the cable, and its processability is low, such as high viscosity when melting, making it difficult to melt and mold.In particular, by discharging harmful gases such as fluorinated gas in incineration or fire, There is a problem that is not environmentally friendly.

Accordingly, a technology has been developed to replace the insulator 112 constituting some of the pair units 100 among the plurality of pair units 100 with a flame-retardant polyolefin material or double insulation of an inner flame-retardant polyolefin and an outer fluororesin.

However, since flame-retardant polyolefin is a material in which a large amount of flame retardant and additives are mixed with polyolefin resin, the dielectric constant and dielectric loss increase and electrical properties are greatly deteriorated. As a result, the flame retardancy of the cable is deteriorated.

And, in the case of applying a flame-retardant polyolefin, it may be considered that the outer jacket 300 is made of a highly flame-retardant polyvinylchloride (PVC) material in order to minimize the deterioration of the flame retardancy, but this eventually leads to an increase in cable cost. There is.

Therefore, there is an urgent need for a flame-retardant UTP cable that is not environmentally friendly and does not increase the thickness and volume of the cable while securing high flame retardancy of CMP (Communication Plenum) grade without using expensive fluororesin.

An object of the present invention is to provide a UTP cable having high flame retardancy of CMP (Communication Plenum) grade.

In addition, an object of the present invention is to provide a UTP cable that is environmentally friendly and reduces manufacturing cost.

Furthermore, an object of the present invention is to provide a UTP cable in which thickness and volume are not increased even though the insulator achieves sufficient flame retardancy and electrical properties at the same time, and thus the thickness and volume are not increased as a whole.

In order to solve the above problems, the present invention,

A plurality of pair units formed by twisting a plurality of conductive wires including a conductor and an insulator surrounding the conductor, and an outer jacket surrounding the plurality of pair units; In the plurality of pair units, at least one first pair unit formed by twisting a plurality of conducting wires including an insulator formed from a flame-retardant polyolefin resin composition and a plurality of conducting wires including an insulator formed from a non-flammable polyolefin resin composition are twisted together. It provides a CMP flame retardant grade UTP cable, characterized in that it comprises at least one second pair unit formed by the load.

Here, the flame-retardant polyolefin resin composition has a dielectric constant of 2.9 or less, a Limited Oxygen Index (LOI) of 30% or more, a smoke density of 500 or less as measured according to ASTM E662, and a melt flow rate (2.16kg, 230°C). It provides a CMP flame-retardant grade flame-retardant UTP cable, characterized in that 5 g/10min or more.

In addition, the outer jacket is from a resin composition comprising a flame-retardant polyvinyl chloride resin having a limiting oxygen index (LOI) of 45 to 60%, and 5 to 10 parts by weight of a metal hydroxide flame retardant based on 100 parts by weight of the flame-retardant polyvinyl chloride resin. It provides a CMP flame retardant grade flame retardant UTP cable that is formed.

Here, the second pair unit is one, the twist pitch of the second pair unit is shorter than the twist pitch of each of the plurality of first pair units, and the twist pitch of the conductor wire is the shortest among the plurality of first pair units. It provides a CMP flame-retardant grade flame-retardant UTP cable, characterized in that the one pair unit is disposed on the diagonally spaced apart from the second pair unit.

In addition, the second pair units are two, the twist pitch of each of the two second pair units is shorter than the twist pitch of each of the plurality of first pair units, and the two second pair units are diagonally spaced apart from each other most It provides a CMP flame retardant grade flame retardant UTP cable, characterized in that it is placed in position.

In addition, a twist pitch of the first pair unit is 0.6 to 1.2 inches, and the twist pitch of the second pair unit is 0.3 to 0.53 inches. It provides a CMP flame retardant grade flame retardant UTP cable.

Further, it provides a CMP flame retardant grade flame retardant UTP cable, characterized in that the difference in transmission speed between the first pair unit and the second pair unit is 45 ns or less.

On the other hand, it provides a CMP flame retardant grade flame retardant UTP cable, characterized in that the volume of the insulator forming the second pair unit is 85 to 95% of the volume of the insulator forming the first pair unit.

In addition, the flame-retardant polyolefin resin composition includes a base resin comprising 50 to 90 parts by weight of a polypropylene block copolymer and 10 to 50 parts by weight of a thermoplastic elastomer including an ethylene propylene copolymer, based on 100 parts by weight of the base resin, a metal hydroxide flame retardant It provides a CMP flame retardant grade flame retardant UTP cable comprising 50 to 150 parts by weight, and 30 to 100 weight of a halogen-based flame retardant aid.

Here, the flame-retardant polyolefin resin composition provides a CMP flame-retardant grade flame-retardant UTP cable, characterized in that it further comprises 2 to 10 parts by weight of a reactive polyolefin into which a polar group is introduced based on 100 parts by weight of the base resin.

On the other hand, the non-flammable polyolefin resin composition provides a CMP flame retardant grade flame retardant UTP cable, characterized in that it comprises a high-density polyethylene resin.

In addition, the metal hydroxide flame retardant provides a CMP flame retardant grade flame retardant UTP cable, characterized in that it contains magnesium hydroxide (Mg(OH) ₂ ).

Here, the metal hydroxide flame retardant provides a CMP flame retardant grade flame retardant UTP cable, characterized in that the surface is not treated.

In addition, the resin composition forming the outer jacket, based on 100 parts by weight of the flame-retardant polyvinyl chloride, characterized in that it further comprises 2 to 5 parts by weight of zinc borate, it provides a CMP flame retardant grade flame-retardant UTP cable.

Further, the resin composition forming the outer jacket provides a CMP flame retardant grade flame retardant UTP cable, characterized in that the limiting oxygen index (LOI) is 60% or more.

On the other hand, it provides a CMP flame-retardant grade flame-retardant UTP cable, characterized in that it further comprises a separator including a plurality of partition walls disposed between each of the plurality of pair units to maintain the arrangement of the plurality of pair units.

In addition, it provides a CMP flame-retardant grade flame-retardant UTP cable, characterized in that it further comprises a lip cord to facilitate the stripping of the outer jacket.

The flame-retardant UTP cable according to the present invention exhibits an excellent effect of maintaining high flame retardancy of CMP (Communication Plenum) grade even though a fluororesin material insulator is not applied by a specific flame-retardant insulator and an outer jacket.

In addition, the flame-retardant UTP cable according to the present invention discharges harmful gases such as fluorinated gas during incineration or fire, and does not apply an insulator made of fluorine resin, which is not environmentally friendly and expensive. Show.

Further, the flame-retardant UTP cable according to the present invention exhibits an excellent effect of not increasing the thickness and volume of the cable despite achieving sufficient flame retardancy and electrical properties at the same time by varying the insulating material used in the pair unit.

1 schematically shows a cross-sectional structure of a 4-pair UTP cable wrapped in an outer jacket with four pair units.
Figure 2 schematically shows a cross-sectional structure of a CMP flame retardant grade UTP cable according to an embodiment of the present invention.
3 schematically shows a longitudinal sectional structure of a CMP flame retardant grade UTP cable according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art. The same reference numbers throughout the specification denote the same elements.

2 is a schematic cross-sectional view of a CMP flame retardant grade UTP cable according to an embodiment of the present invention.

As shown in Figure 2, the CMP flame retardant grade UTP cable according to the present invention is a plurality of conductive wires 110 formed by insulating a conductive metal wire 111 with an insulator 112, preferably two twisted to each other at a predetermined pitch. It includes a plurality of pair units 100 formed by a load and an outer jacket 300 surrounding the plurality of pair units 100.

The standards and materials of the conductive metal wire 111 comply with the UTP cable international standard (ANSI/TIA/EIA 568A). For example, the conductive metal wire 111 may be made of a material such as copper, annealed copper, tinned copper, or the like, and may be a solid wire or a stranded wire. , Preferably, it may be a twisted pair to improve the flexibility (flexibility) of the UTP cable. In addition, when the conductive metal wire 111 is a single wire, the outer diameter may be about 0.5 to 0.6 mm, and in the case of a stranded wire, the small wire diameter may be about 0.203 mm.

The insulator 112 constituting one or more pair units 100 of the plurality of pair units 100 may include a flame retardant polyolefin (FRPO) resin composition, preferably a flame retardant polypropylene (FRPP) resin composition.

The flame-retardant polyolefin resin composition may include, for example, a base resin, a flame retardant, a flame retardant auxiliary, and other additives. The base resin may include, for example, 50 to 90 parts by weight of a polyolefin resin and 10 to 50 parts by weight of a thermoplastic polyolefin elastomer resin, based on a total of 100 parts by weight. In addition, 2 to 10 parts by weight of a reactive polyolefin into which a polar group is introduced may be additionally included to improve initial modulus.

The polyolefin resin may be a homopolymer or a random or block copolymer, and a block copolymer is preferable in consideration of cold resistance and mechanical properties. When the content of the polyolefin resin is less than 50 parts by weight, the hardness decreases, causing the insulator to be pressed when twisting the conductor wire 110 for manufacturing the pair unit 100, the scratch resistance decreases, and the appearance may be rough during high-speed extrusion. On the other hand, if it exceeds 90 parts by weight, elongation and flexibility may be deteriorated. The polyolefin may preferably have a melting flow rate (MFR) (2.16 kg, 230° C.) of 3 to 15.

The thermoplastic polyolefin elastomer resin may be, for example, a copolymer of ethylene and other α-olefins, for example, an ethylene propylene copolymer, or a thermoplastic elastomer including a styrene-ethylene-butylene-styrene copolymer, and the like. In consideration of properties and the like, a thermoplastic elastomer including an ethylene-α-olefin copolymer is preferred. In addition, the reactive polyolefin into which the polar group is introduced is preferably a polypropylene grafted with maleic anhydride, glycidyl methacrylate, or the like. The thermoplastic polyolefin elastomer resin may preferably have an MFR (2.16 kg, 230°C) of 3 to 15.

The flame retardant may be added in an amount of 50 to 150 parts by weight based on 100 parts by weight of the base resin. The flame retardant may be, for example, a metal hydroxide such as magnesium hydroxide or aluminum hydroxide, and may not be surface-treated or may be surface-treated with silane or stearic acid. If the content of the flame retardant is less than 50 parts by weight, flame retardancy may be insufficient, whereas if the content of the flame retardant is more than 150 parts by weight, processability and electrical properties may be deteriorated.

The flame retardant aid may be a halogen-based flame retardant aid such as a bromine-based flame retardant, an antimony-based flame retardant aid such as antimony trioxide, etc., and based on 100 parts by weight of the base resin, the halogen-based flame retardant aid is 30 to 100 parts by weight, and an antimony flame retardant aid It may be added in 5 to 100 parts by weight.

If the content of the halogen-based flame retardant aid is less than 30 parts by weight and the content of the antimony-based flame retardant aid is less than 5 parts by weight, there is no effect of increasing the flame retardancy. I can. As the other additives that may be included in the flame-retardant polyolefin resin composition, a small amount of lubricant, antioxidant, processing aid, etc. may be used according to other purposes.

The flame retardant polyolefin resin composition preferably has a dielectric constant (@1MHz) of 2.9 or less, a limiting oxygen index (LOI) of 30% or more, a smoke density (ASTM E662, Flaming mode, Dm) of 500 or less, and MFR (2.16 kg, 230). °C) is 5 g/10min or more, and exhibits sufficient electrical properties, mechanical properties, flame retardancy, and retardation properties, etc. by the above configuration and physical properties.

The insulator 112 constituting one or more pair units 100 of the plurality of pair units 100 is a non-flammable insulating resin composition, preferably a polyolefin resin such as polyethylene or polypropylene, more preferably a high density polyethylene resin It may be a composition containing. Polyethylene vinyl acetate (EVA), polyvinyl chloride (PVC), etc. can be considered as non-flammable insulation materials, but EVA, PVC, etc. have polar groups in the molecule, increasing dielectric constant and dielectric loss, so UTP cables that require high transmission speed It is not suitable as an insulating material for

Unlike the flame-retardant polyolefin resin composition, the non-flammable insulating resin composition has excellent electrical properties because no flame retardant, additives, etc., which increase the dielectric constant, are added, and thus, compared to the volume of the insulator formed by the flame-retardant polyolefin resin composition. Since it has a volume of 85 to 95%, it is possible to achieve miniaturization and weight reduction of UTP cables.

3 schematically shows a longitudinal sectional structure of a CMP flame retardant grade UTP cable according to an embodiment of the present invention.

2 and 3, the CMP flame-retardant grade UTP cable according to the present invention has a plurality of pair units 100 adjacent to each other in one outer jacket 300, so that each pair unit 100 A phenomenon in which noise is generated in the transmission signal of another adjacent pair unit 100 by an electromagnetic field formed by a flowing current may be adversely affected, that is, a crosstalk phenomenon may occur, and such a crosstalk phenomenon may be suppressed or minimized. In order to do so, each pair unit 100 has a structure in which a plurality of conductors 110 are twisted at a constant pitch.

As described above, the insulator 112a of the conducting wire 110a constituting one or more of the first pair units 100a of the plurality of pair units 100 is formed of the flame-retardant polyolefin resin composition, and The insulator 112b of the conducting wire 110b constituting the two pair unit 100b may be formed of the non-flammable insulating resin composition.

Here, since the flame-retardant polyolefin resin and the non-flammable insulating resin have different dielectric constants, the UTP cable including the first and second pair units 100a and 100b composed of these different insulators 112a and 112b has a signal phase difference, reaching Problems such as time delay may occur.

Therefore, the twist pitch of the second pair unit 100b composed of the insulator 112b formed of the non-flammable insulating resin having a relatively low dielectric constant compared to the flame-retardant polyolefin resin whose dielectric constant is increased by the addition of a flame retardant and an additive is set to the second. By designing to be shorter than the twisting pitch of the one pair unit 100a, problems such as the signal phase difference and arrival time delay of the UTP cable can be suppressed or minimized. Here, it is preferable that the difference in transmission speed between the first pair unit 100a and the second pair unit 100b is 45 ns or less.

For example, the twist pitch of the first pair unit 100a may be about 0.6 to 1.2 inches, the twist pitch of the second pair unit 100b may be about 0.3 to 0.53 inches, and the first pair of UTP cables The number of 1 pair units 100a may be 2 to 3, and the number of second pair units 100b may be 1 to 2. The plurality of first pair units 100a may be twisted at different pitches, respectively, and the same applies when there are a plurality of second pair units 100b.

In particular, in the 4-pair UTP cable, the second pair unit (100b) having the shortest twist pitch and the first pair unit (100a) or the second pair unit (100b) having a short twist pitch next to each other are the most spaced apart from each other. It is preferable to be placed in a diagonal position.

In the present invention, the outer jacket 300 may preferably be made of a resin composition including flame-retardant polyvinyl chloride (PVC). The flame retardancy of the flame-retardant polyvinyl chloride (PVC) is preferably 45 to 60%, preferably 50 to 55%, of a Limited Oxygen Index (LOI). Flame-retardant polyvinyl chloride (PVC) of a flame-retardant grade with a limiting oxygen index (LOI) exceeding 60% is very expensive, so there is a problem of excessively increasing the unit cost of UTP cables.

The resin composition constituting the outer jacket 300 may further include a flame retardant in addition to flame retardant polyvinyl chloride (PVC) having a limiting oxygen index (LOI) of 45 to 60%. The flame retardant may preferably include a metal hydroxide such as magnesium hydroxide (Mg(OH) ₂ ) and aluminum hydroxide (Al(OH) ₃ ). The metal hydroxide flame retardant has an endothermic effect due to a dehydration reaction and has a low heat generation effect along with flame retardancy, and has the advantage of no toxic gas.

However, in the case of aluminum hydroxide (Al(OH) ₃ ), it may be decomposed according to the processing temperature when the resin composition for forming the outer jacket 300 is extruded, and as a result, the physical properties and flame retardancy of the outer jacket 300 may be reduced. Because of this, magnesium hydroxide (Mg(OH) ₂ ) is preferred.

The metal hydroxide flame retardant may be added in an amount of 5 to 10 parts by weight based on 100 parts by weight of the flame-retardant polyvinyl chloride (PVC). When the content of the metal hydroxide flame retardant is less than 5 parts by weight, flame retardancy may be insufficient, whereas when the content of the metal hydroxide flame retardant exceeds 10 parts by weight, it may be discharged to the outside during extrusion molding of the outer jacket 300 or deteriorate moldability.

The metal hydroxide flame retardant may have a surface treated with silane or the like to improve compatibility with polyvinyl chloride (PVC), but the flame retardancy of the outer jacket 300 including the metal hydroxide is lowered and the UTP cable Since the unit price may increase, it is preferable not to perform the surface treatment of the metal hydroxide flame retardant from this viewpoint.

The resin composition constituting the outer jacket 300 can improve the limiting oxygen index (LOI) to 50 to 65% by adding the metal hydroxide flame retardant to the flame-retardant polyvinyl chloride (PVC), and at the same time, the limiting oxygen index ( It is much cheaper than flame retardant polyvinyl chloride of flame retardant grade with an LOI) of 60% or more.

The resin composition constituting the outer jacket 300 may further include a flame retardant auxiliary. The flame retardant aid may include inorganic flame retardants such as zinc borate, sodium silicate, molybdenum compound, ammonium phosphate, ammonium carbonate, ammonium polyphosphate, red phosphorus, or a combination thereof, preferably zinc borate.

The metal hydroxide flame retardant added to the resin composition constituting the outer jacket 300 may deteriorate the molding processability, water resistance, and mechanical performance of the resin composition when mixed in a large amount. Therefore, by applying the flame retardant auxiliary, a large amount of the flame retardant is mixed. You can lower your need. In addition, as the flame retardant auxiliary, zinc borate may further improve smoke retardancy, which is a characteristic of suppressing smoke generation.

The flame retardant auxiliary may be 2 to 5 parts by weight based on 100 parts by weight of the flame-retardant polyvinyl chloride (PVC). If the content of the flame retardant auxiliary is less than 2 parts by weight, the effect of increasing flame retardancy and the effect of improving suppression may be insufficient, while if it is more than 5 parts by weight, the moldability and mechanical properties of the resin composition may be reduced.

In the flame-retardant UTP cable according to the present invention, the outer jacket 300 exhibits sufficient flame retardancy and suppression by the above configuration, and at the same time exhibits an effect of lowering the manufacturing cost of the UTP cable.

The flame-retardant UTP cable according to the present invention includes a separator including a plurality of partition walls disposed between each of the plurality of pair units 100 to maintain the arrangement of the plurality of pair units 100 inside the outer jacket 300 ( 400) may additionally be included. The separator 400 performs a function of improving structural stability of the UTP cable by stably maintaining the arrangement of the plurality of pair units 100 and improving the resistance of the outer jacket 300 to external pressure. The separator 400 may be made of a material that is the same as or different from a material constituting the outer jacket 300.

The flame-retardant UTP cable according to the present invention may further include a lip cord 500 inside the outer jacket 300. The lip cord 500 is used to facilitate the peeling of the outer jacket 300, Kevlar aramid yarn, fiber glass epoxy rod, fiber reinforced polyethylene (FRP; Fiber Reinforced) Polyethylene), high-strength fiber, galvanized steel wire, steel wire, etc., can function as a tensile wire that imparts tensile strength to UTP cables.

<Example>

1. Example of the insulating layer made of flame-retardant polyolefin resin

end. Manufacturing example

After preparing the insulating composition according to the Examples and Comparative Examples with the components and contents shown in Table 1 below at 210°C using a twin screw extruder, an insulating specimen was manufactured using a hot press. The units of the contents listed in Table 1 are parts by weight.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Resin 1 70 80 67 95 70 70 Suzy 2 30 20 5 30 30 Suzy 3 30 Suzy 4 3 Flame retardant 1 100 80 70 160 80 Flame retardant 2 60 Flame retardant aid 1 30 40 40 40 30 110 Flame retardant aid 2 20 30 20 30 20 20 Talc 5 10 5 5 Antioxidant One One One One One One Lubricant One One One One One One Processing aid One One One One One One

Resin 1: Polypropylene (MFR: 10g/10min (2.16kg, @230℃))

Resin 2: Ethylene propylene elastomer (MFR: 3.2g/10min (2.16kg, @230℃))

Resin 3: Ethylene propylene elastomer (MFR: 0.6g/10min (2.16kg, @230℃))

Resin 4: Maleic anhydride grafted polypropylene (MFR: 0.9g/10min (2.16kg, @230℃))

Flame retardant 1: Magnesium hydroxide surface-treated with lubricant

Flame retardant 2: Magnesium hydroxide surface-treated with silane

Flame retardant auxiliary 1: Brominated flame retardant

Flame retardant aid 2: Antimony trioxide

I. Property evaluation

(1) Evaluation of mechanical properties

When evaluated according to standard UL444, the elongation of the insulating material must be 100% or more, and the melt flow rate (MFR) (2.16kg, @230℃) measured according to ASTM D1238 must be 5 g/10min or more.

(2) dielectric constant evaluation

In order to satisfy sufficient electrical characteristics, the dielectric constant must be 2.9 or less.

(3) Flame retardancy evaluation

The limiting oxygen index (LOI) of the insulating material should be 30% or more, and the smoke density (ASTM E662, Flaming mode, Dm) should be 500 or less when tested with a 2mm specimen.

The results of evaluating the physical properties are shown in Table 2 below.

Properties unit Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Elongation % 150 300 350 85 120 250 Melt flow rate g/10min 5.5 6.0 5.7 5.5 5.0 3.5 permittivity 2.75 2.88 2.82 2.70 3.21 2.90 Limiting oxygen index % 32.5 34.0 33.0 33.5 35.5 40.0 Smoke density 450 400 430 480 380 650

As shown in Table 2, the insulator of Comparative Example 1 contained an excessive amount of hard polypropylene resin and contained a small amount of the soft elastomer resin, so that the elongation of the composition was insufficient to be less than 100%, and the insulator of Comparative Example 2 was As the flame retardant was included in an excessive amount, the dielectric constant exceeded 2.9 and the electrical characteristics were greatly damaged.In Comparative Example 3, the smoke suppression property greatly exceeded 500 by including an excessive amount of the halogen-based flame retardant auxiliary, and the melt flow rate was also 5 g/ It was confirmed that it did not reach a large amount of 10 min.

On the other hand, Examples 1 to 3, which are insulators used in the UTP cable of the present invention, were found to be excellent in balance in mechanical properties such as elongation and melt flow rate, electrical properties, flame retardancy, and retardation.

2. Examples of outer jacket and UTP cable

end. Manufacturing example

An outer jacket made of a PVC resin composition prepared according to Examples and Comparative Examples with the components and contents shown in Table 3 below at 210°C using a twin screw extruder and an insulating layer made of the insulating composition according to Example 1 Cat. A 5e 4-pair UTP cable specimen was prepared. The units of the content listed in Table 2 below are parts by weight.

Ingredients Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Suzy 200 200 200 200 200 200 200 200 200 Flame retardant 10 20 10 20 - - - 5 30 Flame Retardant
Supplements 5 5 - - - 5 10 5 5

Resin: Flame-retardant polyvinyl chloride (PVC) (manufacturer: Teknor Apex; product name: 910A-60NL)

Flame retardant: magnesium hydroxide

Flame retardant auxiliary: zinc borate

I. Property evaluation

(1) Evaluation of mechanical properties

The tensile strength and elongation of the outer jacket were measured according to the UL444 standard, and the tensile strength should be 1.76kgf/㎟ or more and the elongation rate should be 100% or more.

(2) Flame retardancy evaluation

In accordance with the NFPA 262 standard, flame retardancy and retardation were measured, and the flame propagation indicating flame retardancy should be less than 5 ft, and the smoke density indicating flame retardancy, that is, peak smoke emission and average smoke emission should be less than 0.5 and 0.15, respectively.

The results of the physical property evaluation are as shown in Table 4 below.

Properties Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Tensile strength (kgf/㎟) 1.88 1.82 1.87 1.81 2.01 1.92 1.83 1.93 1.68 Elongation (%) 185 182 191 174 198 188 186 195 164 Flame prop.(ft) 3.5 3.0 4.5 4.0 6.0 6.0 5.5 5.5 3.0 peak smoke emission 0.38 0.35 0.60 0.55 0.75 0.49 0.45 0.47 0.33 average smoke emission 0.11 0.10 0.15 0.15 0.21 0.16 0.14 0.13 0.10

As shown in Table 4, in Comparative Examples 1 to 4, flame propagation was insufficient because a flame retardant was not added to the flame retardant PVC resin constituting the outer jacket or the content was insufficient, and Comparative Example 5 was a flame retardant to the flame retardant PVC resin. It was confirmed that the tensile strength of the outer jacket was greatly damaged due to the addition of excessive amounts.

On the other hand, it was confirmed that the UTP cable to which the outer jacket of Examples 1 to 4 according to the present invention was applied has sufficient mechanical properties and flame retardancy of the outer jacket.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art may variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. You can do it. Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all should be considered to be included in the technical scope of the present invention.

100: pair unit 300: outer jacket
400: separator 500: lip cord

Claims (17)

A plurality of pair units formed by twisting a plurality of conductive wires including a conductor and an insulator surrounding the conductor, and an outer jacket surrounding the plurality of pair units;
In the plurality of pair units, at least one first pair unit formed by twisting a plurality of conducting wires including an insulator formed from a flame-retardant polyolefin resin composition and a plurality of conducting wires including an insulator formed from a non-flammable polyolefin resin composition are twisted together. And one or more second pair units formed by loading,
The flame-retardant polyolefin resin composition includes 50 to 90 parts by weight of a polypropylene block copolymer and 10 to 50 parts by weight of a thermoplastic elastomer including an ethylene propylene copolymer as a base resin, and based on 100 parts by weight of the base resin, a metal hydroxide flame retardant 50 To 150 parts by weight, and a halogen-based flame retardant auxiliary,
The non-flammable polyolefin resin composition comprises a high density polyethylene resin,
The polypropylene block copolymer and the thermoplastic elastomer each have a melt flow rate (MFR) (2.16 kg, 230°C) of 3 to 15 g/10 min,
The outer jacket is a flame-retardant polyvinyl chloride resin and, based on 100 parts by weight of the flame-retardant polyvinyl chloride resin, characterized in that formed from a resin composition comprising 5 to 10 parts by weight of a metal hydroxide flame retardant, CMP flame retardant grade UTP cable. The method of claim 1,
The flame-retardant polyolefin resin composition has a dielectric constant of 2.9 or less, a Limited Oxygen Index (LOI) of 30% or more, a smoke density of 500 or less, as measured according to ASTM E662, and a melt flow rate (2.16kg, 230°C) of 5 G/10min or more, characterized in that, CMP flame retardant grade UTP cable. The method of claim 1,
CMP flame retardant grade UTP cable, characterized in that the limiting oxygen index (LOI) of the flame retardant polyvinyl chloride resin is 45 to 60%. The method according to any one of claims 1 to 3,
The first pair of the second pair unit is one, the twist pitch of the second pair unit is shorter than the twist pitch of each of the plurality of first pair units, and the twist pitch of the conductor wire is the shortest among the plurality of first pair units CMP flame retardant grade UTP cable, characterized in that the unit is disposed on the diagonal line spaced apart from the second pair unit. The method according to any one of claims 1 to 3,
The second pair units are two, the twist pitch of each of the two second pair units is shorter than the twist pitch of each of the plurality of first pair units, and the two second pair units are at a diagonal position most spaced apart from each other. Characterized in that arranged, CMP flame retardant grade UTP cable. The method according to any one of claims 1 to 3,
The twist pitch of the first pair unit is 0.6 to 1.2 inches, and the twist pitch of the second pair unit is 0.3 to 0.53 inches, CMP flame retardant grade UTP cable. The method according to any one of claims 1 to 3,
CMP flame retardant grade UTP cable, characterized in that the difference in transmission speed between the first pair unit and the second pair unit is 45 ns or less. The method according to any one of claims 1 to 3,
CMP flame retardant grade UTP cable, characterized in that the volume of the insulator forming the second pair unit is 85 to 95% of the volume of the insulator forming the first pair unit. The method according to any one of claims 1 to 3,
The flame-retardant polyolefin resin composition comprises 30 to 100 parts by weight of a halogen-based flame-retardant auxiliary and 5 to 100 parts by weight of an antimony-based flame-retardant auxiliary based on 100 parts by weight of the base resin. The method of claim 9,
The flame-retardant polyolefin resin composition, based on 100 parts by weight of the base resin, characterized in that it further comprises 2 to 10 parts by weight of a reactive polyolefin introduced with a polar group, CMP flame-retardant grade UTP cable. delete The method according to any one of claims 1 to 3,
The metal hydroxide flame retardant is characterized in that it contains magnesium hydroxide (Mg(OH) ₂ ), CMP flame retardant grade UTP cable. The method of claim 12,
The metal hydroxide flame retardant is characterized in that the surface treatment, CMP flame retardant UTP cable. The method of claim 3,
The resin composition forming the outer jacket, based on 100 parts by weight of the flame-retardant polyvinyl chloride, characterized in that it further comprises 2 to 5 parts by weight of zinc borate, CMP flame-retardant grade UTP cable. The method according to any one of claims 1 to 3,
The resin composition forming the outer jacket is characterized in that the limiting oxygen index (LOI) is 60% or more, CMP flame retardant grade UTP cable. The method according to any one of claims 1 to 3,
A CMP flame retardant grade UTP cable, characterized in that it further comprises a separator including a plurality of partition walls disposed between each of the plurality of pair units to maintain the arrangement of the plurality of pair units. The method according to any one of claims 1 to 3,
CMP flame retardant grade UTP cable, characterized in that it further comprises a lip cord to facilitate the stripping of the outer jacket.

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