KR20230013480A - Thermal Bonding Composite Fiber With Enhanced Abrasion Resistance - Google Patents

Abstract

The present invention relates to a thermal bonded composite fiber with enhanced abrasion resistance, wherein a first component core portion of the composite fiber is any one of polypropylene (PP) or polyester (PET) resin, and a second component sheath portion is 60 to 98 wt% of polyethylene (PE) blended with 1 to 20 wt% of low melt polyester resin and 1 to 20 wt% of polypropylene (PP), or 80 to 99 wt% of polyethylene (PE) blended with 1 to 20 wt% of polypropylene (PP). The low melt polyester resin is formed from an acid component consisting of terephthalic acid or an ester-forming derivative thereof, and a diol component consisting of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol.

Description

Thermal Bonding Composite Fiber With Enhanced Abrasion Resistance}

The present invention is a heat-sealed composite fiber with enhanced abrasion resistance, and more specifically, it is an invention in which the abrasion resistance is improved by mixing polypropylene (PP) to increase the abrasion resistance of polyethylene (PE) of the sheath part.

Low-density non-woven fabrics with a fabric density of 10 to 45 g/m2 are used as surface materials for paper diapers and sanitary napkins. As the use of nonwoven fabrics has diversified, the properties required for nonwoven fabrics have also become stricter, and there has been a demand for nonwoven fabrics having high strength while maintaining a soft touch.

In order to meet these demands, composite fibers are required which are fine and thermally adhesive, and which not only provide sufficient thermal adhesive strength with a low melting point component but also provide flexibility.

Sheath-core type or side-by-side type composite fibers with polyolefin-based components such as conventional polyethylene and polypropylene as low-melting components and conventional polyolefin-based components such as polyester and polypropylene as high-melting components such as polyester and polypropylene such as polyethylene terephthalate is well known in the past.

In the carding process of manufacturing the sheath-core composite fiber into a nonwoven fabric, polyethylene (PE), which is a sheath, tends to be scratched by mechanical-fiber friction, resulting in increased dust (powder).

If there is a lot of such dust (powder), as a result, the carding process is hindered, and the non-woven fabric uniformity is deteriorated, and it remains on the surrounding non-woven fabric and contaminates the surrounding belt, appearing as carbonized foreign matter, which can cause non-woven fabric defects. .

In addition, there is a problem that the process yield is reduced because the cleaning cycle is shortened in order to suppress the dust generated in this way.

In the present invention, polypropylene ( PP) for the purpose of mixing.

In order to solve the above problems, the present invention is a heat-bonded conjugate fiber with enhanced abrasion resistance, the second component sheath is 60 to 98% by weight of polyethylene (PE), 1 to 20% by weight of a low melting point polyester resin and poly 1 to 20% by weight of propylene (PP) is mixed, or 80 to 99% by weight of polyethylene (PE) is mixed with 1 to 20% by weight of polypropylene (PP), and the low melting point polyester resin is terephthalic acid or An acid component composed of the ester-forming derivative and a diol component composed of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol having enhanced wear resistance. A heat-bonded composite fiber is provided.

In addition, the present invention provides a heat-bonded composite fiber with enhanced abrasion resistance, characterized in that the first component and the second component in the composite fiber have a weight ratio of 80:20 to 20:80.

As described above, in the present invention, in the carding process of manufacturing sheath-core composite fibers into nonwoven fabric, polyethylene (PE), which is a sheath, is scratched by mechanical-fiber friction to prevent generation of dust (powder) It is effective in maintaining the homogeneity of the nonwoven fabric produced by preventing and remaining in the surrounding nonwoven fabric, contaminating the surrounding belt and appearing as carbonized foreign matter, thereby reducing nonwoven fabric defects.

Hereinafter, preferred embodiments of the present invention will be described in detail. First of all, in describing the present invention, detailed descriptions of related known functions or configurations are omitted in order not to obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially', and the like are used in a sense at or approximating that number when manufacturing and material tolerances inherent in the stated meaning are given, and are intended to convey an understanding of the present invention. Accurate or absolute figures are used to help prevent exploitation by unscrupulous infringers of the disclosed disclosure.

As used herein, the terms about, substantially, etc., of degree, are used at or close to the value when manufacturing and material tolerances inherent in the referenced meaning are given, and are used in an accurate or Absolute numbers are used to prevent exploitation by unscrupulous infringers of the stated disclosure.

The present invention relates to thermally bonded composite fibers with enhanced abrasion resistance.

The first component core portion of the composite fiber is any one of polypropylene (PP) or polyester (PET) resin, and the second component sheath portion is polyethylene (PE) with low melting point polyester resin (LM) and polypropylene (PP). , Or, only polypropylene (PP) is mixed as an additive component, and the second component sheath in the mixing ratio is 60 to 98% by weight of polyethylene (PE), 1 to 20% by weight of low-melting polyester resin and polypropylene (PP) 1 to 20% by weight is mixed,

Alternatively, 1 to 20% by weight of polypropylene (PP) is mixed with 80 to 99% by weight of polyethylene (PE).

Polypropylene (PP) commonly used in the first component and the second component is a commonly used commercial composition.

The first component polyester (PET) resin is a polycondensate of aromatic dicarboxylic acid and glycol, and terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc. can be used as aromatic dicarboxylic acid, and ethylene glycol as glycol , 1,3-propanediol, 1,4-butanediol and the like can be used.

Alternatively, the first component polyester (PET) resin is a condensation polymer of aromatic dicarboxylic acid and glycol, and is selected from polyethylene terephthalate, polyethylene 2,6-dinaphthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate. One or a mixture of two or more may be used.

Preferably, polyethylene terephthalate may be used, and it is preferable to use a polyester-based resin having an intrinsic viscosity (IV) of 0.50 to 0.80 dL/g measured according to ASTM 02857.

The polyethylene (PE) of the second component sheath part may use one or a mixture of two or more selected from high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), polypropylene, and ethylene-propylene copolymer. .

Preferably, high-density polyethylene (HDPE) can be used, and the melt flow index (MI, Melting Index) is not particularly limited, but the flow index is 1 to 100 g / lO min, more preferably 5 to 40 g / 10 min. it would be preferable

The low-melting polyester resin (LM) contains an acid component composed of terephthalic acid or an ester-forming derivative thereof, and 2-methyl-1,3-propanediol, 2-methyl-1,3 - It is formed of a diol component composed of pentanediol (2-Methyl 1,3 Pentanediol) and ethylene glycol (EG).

The 2-methyl-1,3-propanediol of the low-melting polyester resin used in the present invention has a methyl group bonded to the second carbon to facilitate the rotation of the polymer main chain and acts as if it were a polymer end, thereby providing freedom between the main chains. By widening the space, the flowability of the entire molecular chain is increased. This makes the polymer amorphous and has the same thermal properties as isophthalic acid. Due to the flexible molecular chain present in the polymer main chain, it improves elasticity and improves the tear property during binding to nonwoven fabric.

That is, 2-methyl-1,3-propanediol is formed by adding methyl to the ethylene chain bound to terephthalate.

By including a group (-CH3) as a side chain to secure space for rotation of the main chain of the polymerized resin, the degree of freedom of the main chain is increased and the crystallinity of the resin is reduced, thereby increasing the softening point (Ts) and/or glass transition temperature (Tg). ) can be adjusted. This may exhibit the same effect as the case of using isophthalic acid (IPA) containing an asymmetric aromatic ring in order to lower the crystallinity of a conventional crystalline polyester resin.

Like 2-methyl-1,3-propanediol, the 2-methyl-1,3-pentanediol has a methyl group bonded to the second carbon to facilitate rotation of the polymer main chain and to impart low melting point characteristics to the polyester resin. It has a longer molecular chain than 2-methyl-1,3-propanediol, which increases the melt viscosity of the polyester resin and prevents the melt viscosity from rapidly decreasing at high temperatures.

The low melting point polyester resin of the present invention formed of the diol component as described above is 20 to 50 moles of 2-methyl-1,3-propanediol of the low melting point polyester resin in order to improve the low melting point property and adhesiveness % will be preferred.

When the 2-methyl-1,3-pentanediol is contained in less than 001 mol% of the diol component, the effect of improving the melt viscosity is insignificant, and when the 2-methyl-1,3-pentanediol is contained in the diol component, the melt viscosity increases rapidly and the spinning processability may deteriorate. 2-methyl-1,3-pentanediol may preferably contain 0.01 to 5 mol% of the diol component.

It is most preferable that the 2-methyl-1,3-pentanediol contains 0.05 to 2 mol%.

The low melting point polyester resin containing the 2-methyl-1,3-pentanediol is 220 ℃

The difference between the melt viscosity and the melt viscosity at 260°C is 600 poise or less, and the melt viscosity does not rapidly decrease at high temperatures.

The lower the difference between the melt viscosity of the low-melting polyester resin at 220° C. and the melt viscosity at 260° C., the lower the better.

As described above, the low melting point polyester resin of the present invention containing 2-methyl-1,3-propanediol and 2-methyl-1,3-pentanediol has a softening temperature of 100 ° C to 150 ° C, and a glass transition temperature 50 ℃ to 90 ℃, it has excellent physical properties with an intrinsic viscosity of 0.50 dl / g or more.

In addition, it is preferable that the composite fiber is formed in a weight ratio of 80:20 to 20:80 between the first component and the second component.

Hereinafter, an example of a method for producing a thermally bonded composite fiber with enhanced abrasion resistance according to the present invention is shown, but the present invention is not limited to the examples.

Example 1

As the first component polypropylene (PP) of the core part and the second component composition of the sheath part, polyethylene (PE), low melting point polyester resin (LM) and polypropylene (PP) are 98% by weight: 1% by weight: 1% by weight Then, the core part and the sheath part were put into an extruder at a weight ratio of 50:50 and melted.

The melted first and second component compositions were introduced into a conventional sheath-core soft composite spinning apparatus and then spun at a spinning speed of 800 m/min. The composite fibers spun at a temperature higher than the glass transition temperature of polyethylene terephthalate were stretched and oriented 3.0 to 4.0 times, crimped, and cut to 38 to 64 mm to prepare soft heat-sealed composite fibers according to the present invention.

The prepared composite fiber was made of 60GSM nonwoven fabric and bent to prepare a filter.

Example 2

As the second component composition, polyethylene, low melting point polyester resin (LM), and polypropylene (PP) are 80% by weight: 19% by weight: 1% by weight, except that the ratio is the same as in Example 1.

Example 3

Same as Example 1 except that the first component composition is polyester (PET).

Example 4

80% by weight of polyethylene (PE) as the second component composition. Same as Example 3 except that 20% by weight of polypropylene (PP).

Comparative Example 1

As the second component composition, polyethylene and low melting point polyester resin (LM) are the same as in Example 1 except that the ratio is 70% by weight: 30% by weight.

Comparative Example 2

Same as Example 1 except that the second component composition is polyethylene.

Comparative Example 3

As the second component composition, polyethylene and low melting point polyester resin (LM) are the same as in Example 1 except that the ratio is 60% by weight: 30% by weight.

division Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 1 ingredient PP PP PET PET PET PP PP 2 ingredients PE PE PE PE PE PE PE 2-component additives LM/PP LM/PP LM/PP PP LM - LM Two-component (PE/LM/PP)% by weight 98/1/1 80/19/1 98/1/1 80/0/20 70/30/0 100/0/0 60/40/0 Sacrificiality Good Good Good Good Good error Good Thermal bonding temperature ℃ 137 138 137 138 138 - 138 Cleaning cycle (hr) over 48 over 48 over 48 over 48 over 24 - within 24 Uniformity of non-woven fabric Good Good Good Good commonly - commonly Carbonized foreign matter (case, per 100m) 0 times 0 times 0 times 0 times 3rd time - 3rd time

Examples 1 to 4 show that polypropylene is added as a two-component, so that the weaving properties are good, the thermal bonding temperature is normal (135 ~ 1.40 ℃), the cleaning cycle is 48 hr or more, the nonwoven fabric is good, and the carbonization is 0 times good.

Comparative Examples 1 and 3 are: two-component polypropylene-free, good weaving, thermal bonding temperature is normal, but cleaning cycle is less than 24 hr (yield decrease), uniformity is normal, and dust (powder) is generated with 3 cases of carbonized foreign matter. there is.

Comparative Example 2 had no two-component additives and had poor fabrication properties.

Claims (2)

In the heat-bonded composite fiber with enhanced abrasion resistance,
The first component core portion of the composite fiber is any one of polypropylene (PP) or polyester (PET) resin,
The second component sheath part is a mixture of 60 to 98% by weight of polyethylene (PE), 1 to 20% by weight of low melting point polyester resin and 1 to 20% by weight of polypropylene (PP),
Or a mixture of 1 to 20% by weight of polypropylene (PP) in 80 to 99% by weight of polyethylene (PE),
The low-melting polyester resin is composed of an acid component composed of terephthalic acid or an ester-forming derivative thereof, and a diol component composed of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol. Heat-sealed composite fiber with enhanced abrasion resistance characterized by being formed.
According to claim 1,
The composite fiber is a heat-bonded composite fiber with enhanced abrasion resistance, characterized in that the first component and the second component have a weight ratio of 80:20 to 20:80.