KR20240096048A - A low-temperature heat-sealing synthetic resin composition and a sealant film prepared by including the same - Google Patents

Abstract

The sealant film manufactured including the low-temperature heat-sealable resin composition of the present invention can be heat-sealed at low temperatures and can have excellent heat-sealing strength even when heat-sealed at low temperatures, and the laminated film manufactured including the sealant film Because it has excellent heat resistance, optical properties, and mechanical properties, it can be usefully used as a flexible packaging material for retort foods that require heat resistance and mechanical properties.

Description

Low-temperature heat-sealing resin composition and a sealant film prepared including the same {A low-temperature heat-sealing synthetic resin composition and a sealant film prepared by including the same}

The present invention provides a low-temperature heat-sealable resin composition capable of heat-sealing at low temperatures, and a sealant film and laminated film manufactured including the same.

Conventional flexible packaging is used as a laminated film made by heat-sealing a sealant film manufactured by casting polypropylene on a base film to block water vapor, odor, and oxygen.

These flexible packaging materials have been used as base films made of nylon or PET, which has low gas permeability and good mechanical strength.

However, in order to heat-seal a base film made from nylon or PET with a sealant film made from polypropylene, it must be heat-sealed at over 160°C, which requires a lot of heat energy, making it uneconomical. In addition, flexible packaging materials manufactured including base films made from nylon and PET and polypropylene sealant films had poor recyclability because molten nylon or PET and polypropylene could not be easily separated during the recycling process.

Therefore, the current flexible packaging material is replaced with a biaxially oriented polypropylene (BOPP, Biaxially Oriented Polypropylene) film as the base film to solve the problems of low recyclability and low economic efficiency of flexible packaging materials manufactured including the base film made from nylon or PET. It is becoming.

The flexible packaging material manufactured including the BOPP base film and the polypropylene sealant film must be heat-sealed at a high temperature of 140 ℃ or higher in order to have a commercially acceptable level of heat-sealing strength, but the flexible packaging material manufactured by heat-sealing at a high temperature of 140 ℃ or higher Packaging materials cause wrinkles to occur.

Therefore, flexible packaging materials using BOPP as a base film inevitably use a sealant film as a material with excellent heat sealing strength even at low temperatures.

In order for the sealant film of the flexible packaging material to have excellent heat sealing strength at low temperatures, polypropylene must be mixed with a thermoplastic resin with a low melting point, but the manufactured flexible packaging material has a sharp decline in mechanical strength, heat resistance, and optical properties, resulting in excellent mechanical strength. It was difficult to apply it to flexible packaging materials for retort foods, which require strength, excellent heat resistance, and excellent optical properties.

Therefore, there is a need for a new resin composition for sealant film that can not only have excellent heat sealing strength even when heat sealed at low temperatures, but also can have high heat resistance required for flexible packaging materials for retort foods, etc.

Republic of Korea Patent Publication No. 10-1994-0021254 A (1994.10.17)

One embodiment is to provide a low-temperature heat-sealable resin composition that can be manufactured into a sealant film having excellent heat-sealing strength even at low temperatures in a flexible packaging material using the BOPP as a base film.

One embodiment provides a heat-sealable resin composition capable of producing a layered film that not only has the excellent low-temperature heat-sealing strength, but also has excellent mechanical strength, excellent heat resistance, and excellent optical properties, and a sealant film manufactured including the same. .

The low-temperature heat-sealable resin composition of the present invention includes (a) a propylene-based polymer, (b) a propylene-butylene copolymer, (c) a (meth)acrylate-based copolymer, and (d) a fatty acid amide compound.

As one embodiment, the propylene-based polymer may include any one or two or more selected from propylene homopolymer, propylene-ethylene copolymer, and propylene-ethylene-butylene copolymer.

As one embodiment, the propylene-butylene copolymer may contain 50 mol% or more of butylene repeating units based on the total repeating units.

As one embodiment, the low-temperature heat-sealable resin composition may include 10 to 30% by weight of propylene-butylene copolymer.

As one embodiment, the (meth)acrylate-based copolymer may be a copolymerization of C ₁ -C ₆ alkyl (meth)acrylate and any one or two or more selected from ethylene, propylene, and butylene.

As one embodiment, the low-temperature heat-sealable resin composition may include 1 to 10% by weight of a (meth)acrylate-based copolymer.

As one embodiment, the fatty acid amide compound may include one or two or more selected from oleic acid amide, erucamide, ethylene-bis-oleamide, behenamide, and ethylene-bis-steamide.

As one embodiment, the low-temperature heat-sealable resin composition may include 0.1 to 1% by weight of a fatty acid amide compound.

As one embodiment, the low-temperature heat-sealable resin composition may further include one or more additives selected from plasticizers, lubricants, stabilizers, viscosity modifiers, processing aids, flame retardants, enhancers, and dispersants.

As an embodiment, the low-temperature heat-sealable resin composition may have a transferred amount (ΔE) of the fatty acid amide compound that satisfies Equation 1 below.

[Equation 1]

Transferred amount of fatty acid amide compound (△E) = [(E ₁ -E ₂ )/E ₁ ]≤0.05

(In Equation 1 above, E ₁ is the weight of the initially measured sample, and E ₂ is the weight of the specimen measured at room temperature for 48 hours with the fatty acid amide compound transferred to the surface removed.)

As one embodiment, the low-temperature heat-sealable resin composition may be heat-sealed at 100° C. and have a heat-sealing strength of 150 to 500 g/25 mm as measured by ASTM F88.

As one embodiment, the low-temperature heat-sealable resin composition may be heat-sealed at 110° C. and have a heat-sealing strength of 450 to 1,500 g/25 mm as measured by ASTM F88.

The sealant film of the present invention is manufactured including the low-temperature heat-sealable resin composition.

The present invention provides a heat-sealed laminated film including one or more of the sealant films.

As one embodiment, the laminated film may have a haze of 5% or less as measured by ASTM D1003.

Even when heat-sealed at a low temperature of 100°C, the low-temperature heat-sealable resin composition according to the present invention may have a heat-sealing strength of 150 to 500 g/25 mm as measured by ASTM F88.

The low-temperature heat-sealable resin composition according to the present invention has excellent bleeding resistance, and a sealant film manufactured including it can maintain excellent transparency for a long time.

The laminated film manufactured including the sealant film according to the present invention not only has excellent heat sealing strength of a sealant film, excellent mechanical properties and excellent optical properties, but also has excellent heat resistance, so it can be used as a flexible packaging material for retro food. It can be used as

Therefore, the low-temperature heat-sealable resin composition of the present invention maintains excellent heat resistance and can have excellent heat-sealing strength and heat-sealing processability even when heat-sealed at low temperatures, and sealant films and laminates manufactured including it have excellent mechanical properties. , It has excellent optical and thermal properties and can be usefully used as a flexible packaging material.

Hereinafter, the low-temperature heat-sealable resin composition according to the present invention and the sealant film manufactured including the same will be described in detail. At this time, if there is no other definition in the technical and scientific terms used, they have meanings commonly understood by those skilled in the art to which this invention pertains, and the following description will not unnecessarily obscure the gist of the present invention. Descriptions of possible notification functions and configurations are omitted.

As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly dictates otherwise.

In addition, the numerical range used in this specification includes the lower limit and upper limit and all values within the range, increments logically derived from the shape and width of the defined range, all double-defined values, and the upper limit of the numerical range defined in different forms. and all possible combinations of the lower bounds. Unless otherwise specified in the specification of the present invention, values outside the numerical range that may occur due to experimental error or rounding of values are also included in the defined numerical range.

The term “comprises” in this specification is an open description with the same meaning as expressions such as “comprises,” “contains,” “has,” or “characterized by” elements that are not additionally listed; Does not exclude materials or processes.

Conventional flexible packaging materials were used by heat-sealing a base film of polyamide-based film or polyester-based film and polypropylene sealant film, but this required high thermal energy as heat-sealing strength at a commercially acceptable level was achieved only at high temperatures of 160°C or higher. . In addition, the flexible packaging material contains polyamide-based resin, polyester-based resin, and polypropylene resin, so when it was intended to be recycled, it could not be easily separated, resulting in poor recyclability.

In order to solve the above problems of conventional flexible packaging materials, flexible packaging materials including a base film of polypropylene sealant film and biaxially oriented polypropylene (BOPP), which does not require a separation process, are being used.

However, the flexible packaging material using the BOPP as a base film must be heat-sealed at a high temperature of 140 ℃ or higher to have a commercially acceptable heat-sealing strength. However, if heat-sealed above 140 ℃, wrinkles occur, so it can be heat-sealed at a high temperature of 140 ℃ or higher. Due to the limited heat sealing temperature that requires heat sealing at low temperatures, it was difficult to manufacture flexible packaging materials with excellent heat seal strength and excellent surface properties.

Therefore, in order to use BOPP as a base film for the flexible packaging material, a thermoplastic resin with a low melting point must be mixed in order to have excellent heat-sealing strength even when heat-sealed at low temperatures. However, a resin composition mixed with a resin with a low melting point inevitably deteriorates heat resistance, mechanical strength, and optical properties, so a new resin composition that maintains excellent heat resistance, excellent mechanical strength, and excellent optical properties, and has excellent low-temperature heat sealability is needed. This is the situation.

As a result of much research to solve the above problems, (a) polypropylene-based polymer, (b) polypropylene-butylene copolymer, (c) (meth)acrylate-based copolymer, and (d) fatty acid amide compound. By inventing a low-temperature heat-sealable resin composition having excellent low-temperature heat-sealability without deteriorating heat resistance, the present invention has been completed.

Hereinafter, the propylene-based polymer contained in the low-temperature heat-sealable resin composition will be described.

In one embodiment, as a component of the low-temperature heat-sealable resin composition, the propylene-based polymer may include any one or two or more selected from propylene homopolymer, propylene-ethylene copolymer, and propylene-ethylene-butylene copolymer. there is.

The propylene-based polymer has excellent processability and can have heat resistance, mechanical properties, and optical properties at a level that can be used as a sealant film for flexible packaging materials.

Specifically, propylene homopolymer may be preferred in terms of excellent heat resistance, and propylene-ethylene copolymer or propylene-ethylene-butylene copolymer may be preferred in terms of excellent heat sealability, but those skilled in the art will be able to use these. Since it may be adjustable, it is not limited as long as it does not deteriorate the physical properties of the low-temperature heat-sealable resin composition.

More specifically, the propylene-ethylene copolymer may have heat resistance suitable for use as a flexible packaging agent for retorts and a lower heat sealing temperature than propylene homopolymer, and the propylene-ethylene-butylene copolymer may include propylene homopolymer and propylene-ethylene. Since it can have a lower heat-sealing temperature than the copolymer, the physical properties of the low-temperature heat-sealable resin composition produced can be easily adjusted without deteriorating heat resistance.

As an embodiment, the melting temperature of the propylene-based polymer may be 120 to 160°C, and specifically, the melting temperature of the propylene homopolymer is 150 to 160°C, the melting temperature of the propylene-ethylene copolymer is 130 to 150°C, and The melting temperature of the propylene-ethylene-butylene copolymer may be 120 to 140° C., but is not limited thereto.

Since the propylene-based polymer has a melting temperature in the above range, a low-temperature heat-sealable resin composition containing it can not only have excellent processability, but also have heat resistance at a level that can be used as a flexible packaging material for retort foods.

Since the propylene-based polymer has a melting temperature in the above range, a low-temperature heat-sealable resin composition containing it can not only have excellent processability, but also have heat resistance at a level that can be used as a flexible packaging material for retort foods.

As an embodiment, in terms of excellent processability, the propylene-based polymer may have a melt flow index (temperature: 230° C., load: 2.16 kg) of 1.0 to 10.0 g/10 min as measured by ASTM D1238, but may be used as a sealant film. If processing is possible, there are no restrictions.

The specific melt flow index (temperature: 230°C, load: 2.16 kg) of the propylene-based polymer is a non-limiting example, and the melt flow index of the propylene homopolymer is 2.0 to 5.0 g/10min, 2.5 to 4.0 g/10min, or It may be 3.0 to 3.8 g/10min, and the melt flow index of the propylene-ethylene copolymer may be 1.0 to 3.0 g/10min, 1.5 to 2.5 g/10min or 1.5 to 2.0 g/10min, propylene-ethylene-butylene The copolymer may be 5.0 to 8.0 g/10min, 6.0 to 8.0 g/10min or 6.5 to 8.0 g/10min, but is not limited thereto.

As one embodiment, the propylene-based polymer may have a weight average molecular weight of 50,000 to 500,000 g/mol, and specifically 100,000 to 400,000 g/mol, but may have a weight average molecular weight of 50,000 to 400,000 g/mol, which impairs the physical properties of the low-temperature heat-sealable resin composition containing it. If not, this is not restricted.

The weight average molecular weight of the propylene-based polymer is not specifically limited to a measurement method, but a solution of an acrylic copolymer dissolved in tetrohydrofuran is measured using gel permeation chromatography (GPC) equipment (Waters) using a column heater (ALLCOLHTRB). It may be measured at 40°C and with a mobile phase solvent flow rate of 1.0 mL/min.

Propylene-based polymers having a weight average molecular weight in the above range may have excellent miscibility with propylene-butylene copolymers, (meth)acrylate-based copolymers, and fatty acid amide compounds, and may have excellent film processability, but those skilled in the art will If it is at a recognizable level, it is not limited.

As an embodiment, the low-temperature heat-sealable resin composition may include 60 to 80% by weight of a propylene-based polymer, specifically 65 to 80% by weight, and more specifically 70 to 80% by weight. .

The low-temperature heat-sealable resin composition does not limit the content of the propylene-based polymer as long as it has a usable level of heat-sealing strength and heat resistance. However, the low-temperature heat-sealable resin composition may preferably contain the propylene-based polymer in the above content in terms of maintaining heat resistance, mechanical properties, and optical properties.

Hereinafter, the propylene-butylene copolymer of the low-temperature heat-sealable resin composition will be described.

The propylene-butylene copolymer may have excellent miscibility with the propylene-based polymer, and the low-temperature heat-sealable resin composition containing it maintains heat resistance, mechanical properties, and optical properties, and can be heat-sealed at a low temperature of 100 to 120 ° C. Even so, it can have excellent heat sealing strength.

As measured in the present invention, the low-temperature heat-sealable resin composition containing an ethylene-propylene copolymer with a density of 0.862 g/cm3 does not satisfy the low-temperature heat-sealing strength, so the propylene-butylene copolymer It may be a desirable embodiment to necessarily include coalescence.

In addition, although not specifically tested, if it contains a propylene-based copolymer containing an alkylene repeating unit with a higher carbon number than butylene, it cannot have mechanical strength, optical strength and heat resistance, so the low-temperature heat-sealable resin composition is propylene-butyl Including a ren copolymer may be a preferred embodiment.

As an embodiment, the propylene-butylene copolymer may contain 50 mol% or more of butylene repeating units relative to the total repeating units, specifically 55 mol% or more, 60 mol% or more, more specifically It may be 62 mol% or more, 65 mol% or more, and the upper limit is not limited, but may be 85 mol% or less, 80 mol% or less, and 75 mol% or less.

A low-temperature flexible packaging material containing a propylene-butylene copolymer containing butylene repeating units in the above range satisfies the excellent heat resistance, mechanical properties, and optical properties of polypropylene, and has excellent low-temperature heat resistance even when heat-sealed at 100 to 120 ° C. It may have a sealing strength, but as long as it does not impair the physical properties, it is not limited.

In one embodiment, the butylene repeating unit of the propylene-butylene copolymer is not particularly limited as long as it does not impair the physical properties of the low-temperature heat-sealable resin composition to be manufactured, but as a non-limiting example, 1-butylene, cis- It may be derived from any one or two or more selected from 2-butylene, trans-2-butylene, and isobutylene.

Specifically, the propylene-butylene copolymer may be manufactured containing 1-butylene or isobutylene in terms of having superior mechanical strength, and more specifically, it may be manufactured containing 1-butylene. However, it may be used without limitation as long as the low-temperature heat-sealable resin composition containing it can achieve excellent low-temperature heat-sealing strength.

In one embodiment, the propylene-butylene copolymer is not particularly limited, but may have a melting temperature of 50 to 110°C, specifically 50 to 80°C. More specifically, it may be 55 to 70°C.

The propylene-butylene copolymer has a lower melting temperature than the propylene-based polymer, so a low-temperature heat-sealable resin composition containing it can have excellent low-temperature heat-sealing strength, and surprisingly, the mechanical properties, heat resistance, and optical properties do not decline sharply. By not doing so, the above physical properties can be maintained.

As another embodiment, the propylene-butylene copolymer density may be 0.9 g/cm3 or less, specifically 0.8 to 0.9 g/cm3, and more specifically 0.85 to 0.9 g/cm3. .

The density of the propylene-butylene copolymer is not particularly limited as long as it does not impair the physical properties of the low-temperature heat-sealable resin composition to be manufactured, but the propylene-butylene copolymer having a density in the above range may have a low melting point, The low-temperature heat-sealable resin composition containing not only a lower heat-sealing temperature but also a low melt flow index can have excellent processability.

As an embodiment, the propylene-butylene copolymer may have a weight average molecular weight of 100,000 to 1,000,000 g/mol, preferably 200,000 to 500,000 g/mol, as measured by the same method as the propylene-based polymer. It is not intended to be limiting.

As an embodiment, the propylene-butylene copolymer may have a melt flow index (temperature: 190° C., load: 2.16 kg) measured by ASTM D1238 of 0.5 to 20.0 g/10 min, specifically 1.0 to 10.0 g. /10min, more specifically 2.0 to 6.0 g/10min.

A propylene-butylene copolymer having a melt flow index in the above range can have excellent miscibility with a propylene-based polymer, and a low-temperature heat-sealable resin composition containing it can have excellent processability, thereby forming the surface of the manufactured sealant film. Although the properties may be excellent, there is no limitation as long as it does not impair the physical properties of the low-temperature heat-sealable resin composition.

As an embodiment, the low-temperature heat-sealable resin composition may include 10 to 30% by weight of propylene-butylene copolymer, specifically 15 to 30% by weight, and more specifically 20 to 30% by weight. It may include

The low-temperature heat-sealable resin composition containing the propylene-butylene copolymer in the content within the above range has heat resistance at a level that can be used as a retort food flexible packaging material, and can have excellent heat-sealing strength even when heat-sealed at 100 to 120 ° C. may be preferred.

Hereinafter, the (meth)acrylate-based copolymer of the low-temperature heat-sealable resin composition will be described.

The (meth)acrylate-based copolymer may preferably be a copolymer of an alpha-olefin and a (meth)acrylate-based monomer. The (meth)acrylate-based copolymer prepared including the alpha-olefin has excellent miscibility with the propylene-based polymer and propylene-butylene copolymer, and may not impair the physical properties of the low-temperature heat-sealable resin composition containing it. It may be preferred.

In one embodiment, the (meth)acrylate-based copolymer is manufactured by copolymerizing C ₁ -C ₆ alkyl (meth)acrylate and one or a mixture of two or more comonomers selected from ethylene, propylene, and butylene. You can.

Specifically, the (meth)acrylate-based copolymer may be manufactured by copolymerizing C ₁ -C ₆ alkyl (meth)acrylate with one or two or more comonomers selected from ethylene and propylene, and more specifically, It may be manufactured by copolymerizing ethylene with C ₁ -C ₆ alkyl (meth)acrylate.

(meth)acrylate-based copolymers copolymerized including the above comonomers may be preferred because they have excellent transparency, excellent miscibility with propylene-based polymers, and excellent heat resistance, but this is limited. It's not like that.

The C ₁ -C ₆ alkyl (meth)acrylate can be used without limitation in terms of excellent transparency, and non-limiting examples include methyl (meth)acrylate, alkyl (meth)acrylate, and propyl (meth)acrylate. It may be any one or two or more selected from acrylate and butyl (meth)acrylate.

Specifically, tyl (meth)acrylate or ethyl (meth)acrylate may be preferred in terms of superior transparency and excellent mechanical properties compared to (meth)acrylate-based copolymers, but this is not intended to be limiting.

The (meth)acrylate-based copolymer prepared containing the above C ₁ -C ₆ alkyl (meth)acrylate not only has excellent mechanical strength, but the low-temperature heat-sealable resin composition containing it has excellent transparency and excellent transparency. Can have mechanical properties.

As an embodiment, the (meth)acrylate-based copolymer has 10 to 50 mol%, specifically 20 to 50 mol%, of acrylic repeating units derived from C ₁ -C ₆ alkyl (meth)acrylate, based on the total repeating units. It may be mol%, and more specifically, it may be 20 to 40 mol%.

(meth)acrylate-based copolymers containing acrylic repeating units in the above range may be preferred because they can maintain excellent transparency and have excellent heat resistance, unless they impair the physical properties of the low-temperature heat-sealable resin composition containing them. , does not limit this.

As an embodiment, the (meth)acrylate-based copolymer may have a weight average molecular weight of 100,000 to 1,000,000 g/mol, preferably 200,000 to 500,000 g/mol, as measured by the same method as the propylene-based polymer. , it is not intended to limit this.

As another embodiment, the (meth)acrylate-based copolymer may have a melting point of 80 to 100 °C, specifically 85 to 95 °C, and more specifically 90 to 95 °C.

(meth)acrylate that satisfies the weight average molecular weight and melting point in the above range has excellent miscibility with the propylene-based polymer and propylene-butylene copolymer, making it possible to manufacture a low-temperature heat-sealable resin composition with excellent dispersibility. In addition, the manufactured heat-sealable resin composition may be preferred to have a weight average molecular weight and melting point in the above range in terms of maintaining the excellent heat resistance of the propylene-based polymer and also having low-temperature heat-sealing strength, but to limit this. That is not the case.

As one embodiment, the (meth)acrylate-based copolymer may have a melt flow index (temperature: 190° C., load: 2.16 kg) measured by ASTM D1238 of 0.5 to 10 g/10 min, specifically 1.0 to 10 g/10 min. It may be 7.0 g/10min, more specifically 2 to 5 g/10min.

The melt flow index of the (meth)acrylate-based copolymer is not limited as long as it does not impair the physical properties of the low-temperature heat-sealable resin composition to be manufactured, but if the (meth)acrylate-based copolymer satisfies the above melt flow index range, , it may be preferred because it may have excellent miscibility with other polymer components included in the low-temperature heat-sealable resin composition.

As one embodiment, the low-temperature heat-sealable resin composition may include 1 to 10% by weight of a (meth)acrylate-based copolymer, specifically 1 to 7% by weight, and more specifically 1 to 5% by weight. It may be included as a %.

The low-temperature heat-sealable resin composition containing the (meth)acrylate-based copolymer in the content within the above range not only has excellent low-temperature heat-sealing strength even at low temperatures, but also has excellent long-term film processability by preventing migration of the fatty acid amide compound contained therein. It may be preferred because it may have, but the content of the (meth)acrylate-based copolymer included is not limited to the above range unless it impairs the physical properties.

Hereinafter, the fatty acid amide compound of the low-temperature heat-sealable resin composition will be described.

The low-temperature heat-sealable resin composition containing the fatty acid amide compound not only has excellent low-temperature heat-sealing strength, but can also have effects such as excellent miscibility and excellent film processability of the low-temperature heat-sealable resin composition.

As one embodiment, the fatty acid amide compound may include one or two or more selected from oleic acid amide, erucamide, ethylene-bis-oleamide, behenamide, and ethylene-bis-steamide.

Specifically, the fatty acid amide compound may be erucamide or ethylene-bis-oleamide in terms of having better lubricity, but is not limited thereto.

The low-temperature heat-sealable resin composition containing the fatty acid amide compound maintains the excellent heat resistance of propylene-based polymers and can blend propylene-based polymers, propylene-butylene copolymers, and (meth)acrylate-based copolymers with excellent dispersibility. In addition, it can be preferred because it can have more remarkable film processability.

As an embodiment, the low-temperature heat-sealable resin composition may contain 0.1 to 1% by weight of a fatty acid amide compound, specifically 0.1 to 0.7% by weight, and more specifically 0.2 to 0.5% by weight. This is not intended to be limited as long as it does not impair the physical properties of the manufactured low-temperature heat-sealable resin composition.

The low-temperature heat-sealable resin composition containing the fatty acid amide compound in the content within the above range not only has excellent heat resistance, low-temperature heat-sealing strength, and low-temperature heat-sealing processability, but also has excellent film processability, so that the sealant film manufactured including the same can be used. Surface properties can be excellent.

As one embodiment, the low-temperature heat-sealable resin composition may further include nano-silica particles.

The low-temperature heat-sealable resin composition containing the nano-silica particles may have excellent dispersibility and better heat resistance, so it may be preferred, but this is not limited.

The average particle size of the nano-silica particles may be used without limitation as long as it does not impair the physical properties of the low-temperature heat-sealable resin composition, but as a non-limiting example, it may be 1 to 10 ㎛, specifically 1 to 5 ㎛.

As an embodiment, the low-temperature heat-sealable resin composition may include nano-silica particles in an amount of 0.1 to 1% by weight, specifically 0.1 to 0.7% by weight, and more specifically 0.1 to 0.5% by weight, based on the total amount. However, it can be used without limitation as long as it is recognizable to those skilled in the art.

As one embodiment, the low-temperature heat-sealable resin composition may further include one or more additives selected from plasticizers, lubricants, stabilizers, viscosity regulators, processing aids, flame retardants, and viscosity enhancers.

The low-temperature heat-sealable resin composition can further include the above-mentioned additives to control physical properties, thereby allowing it to have physical properties that can be used in other industrial fields other than sealant films.

Hereinafter, the effects of the composition of the low-temperature heat-sealable resin composition will be described.

As one embodiment, the low-temperature heat-sealable resin composition may be heat-sealed at 100° C. and have a heat-sealing strength of 150 to 500 g/25 mm as measured by ASTM F88.

The low-temperature heat-sealable resin composition is not only capable of heat-sealing at 100°C, but also has a heat-sealing strength in the above range, so that the sealant film manufactured including it is a laminated film having remarkable adhesion to the base film and excellent heat-sealing strength. Since the film can be manufactured, the manufactured laminated film can have excellent mechanical strength and transparency.

Specifically, the low-temperature heat-sealable resin composition may be heat-sealed at 100°C, and the heat-sealing strength measured by ASTM F88 may be 200 to 500 g/25 mm, more specifically 250 to 500 g/25 mm.

The low-temperature heat-sealable resin composition may have a heat-sealing strength at 100° C. within the above range by adjusting the compound structure and content of the propylene-based polymer and propylene-butylene copolymer included therein.

As another embodiment, the low-temperature heat-sealable resin composition is heat-sealed at 110°C, and the heat-sealing strength measured by ASTM F88 may be 500 to 1,500 g/25 mm, specifically 640 to 1,500 g/25. ㎜, it may be 870 to 1,500 g/25㎜, and more specifically, it may be 1,100 to 1,500 g/25㎜.

A resin composition having a heat-sealing strength measured by heat-sealing at 110°C in the above range not only has excellent heat-sealing strength even at a low temperature of 100°C, but can also have an even more remarkable heat-sealing strength even at 110°C.

As an embodiment, the low-temperature heat-sealable resin composition may have a transferred amount (ΔE) of the fatty acid amide compound that satisfies Equation 1 below.

[Equation 1]

Amount of fatty acid amide compound transferred (△E) = [(E1-E2)/E1]

(In Equation 1 above, E1 is the weight of the initial measurement sample, and E2 is the weight of the measurement sample measured at room temperature for 48 hours while limiting the fatty acid amiad compound transferred to the surface.)

Specifically, the amount of the fatty acid compound transferred may be 0.04 or less, 0.03 or less, and more specifically 0 to 0.02.

A low-temperature heat-sealable resin composition that satisfies Equation 1 can have excellent film processability for a long period of time, and the sealant film produced from it has excellent long-term surface properties and optical properties because the aliphatic amide compound does not transfer to the surface even if left for a long period of time. It can be preferred because it can have .

That is, the low-temperature heat-sealable resin composition maintains the excellent heat resistance of the propylene-based polymer and can have excellent heat-sealability even at a low temperature of 100 ℃, and the sealant film manufactured including it has excellent heat-sealing properties even when heat-sealed with the base film. It can have excellent surface properties and excellent mechanical strength.

The sealant film of the present invention is manufactured including the low-temperature heat-sealable resin composition.

As one embodiment, the sealant film may be manufactured by further including a masterbatch.

A sealant film manufactured by further including the masterbatch may be preferred because the resin component or additive may have excellent dispersibility, but this is not limited as long as it does not impair the physical properties of the manufactured sealant film.

The masterbatch may refer to a heteroextruded resin containing a high content of resin components, and as a non-limiting example, any one selected from propylene-based polymers, (meth)acrylate-based copolymers, and fatty acid amide compounds. Or it may include two or more.

As one embodiment, the masterbatch may include an anti-blocking agent, but this is not limiting.

The anti-blocking agent may be preferred because it can suppress the friction between wound sealant films during the manufacturing process of the sealant film. The anti-blocking agent is, for example, one selected from NaF, MgF ₂ , CaF ₂ , BaF ₂ , SiO ₂ , BaSO ₄ , CeF ₃ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , ZnS, ZnSe and Ta ₂ O _5. Or, there may be two or more, and specifically, including SiO ₂ can realize excellent sealant film forming properties, but this is not limited as long as it is recognizable to those skilled in the art.

As one embodiment, the sealant film may be manufactured containing 1 to 8 parts by weight of the masterbatch, and specifically, 2 to 6 parts by weight, based on 100 parts by weight of the low-temperature heat-sealable resin composition. However, this is not limited as long as it does not impair the physical properties of the manufactured sealant film.

As an embodiment, the sealant film may have a thickness of 3 to 100 ㎛, specifically 3 to 80 ㎛, and more specifically 3 to 50 ㎛, but it is possible to manufacture a laminated film, which will be described later. There is no limitation as long as it does not impair the physical properties of the laminated film.

As an embodiment, the sealant film may include a low-temperature heat-sealable resin composition and be manufactured by extrusion lamination molding, blown molding, casting molding, or inflation molding. Specifically, it may be manufactured by blow molding or casting molding. Manufacturing may be preferred in terms of having excellent surface performance, but this is not intended to be limited.

The present invention provides a heat-sealed laminated film including one or more of the sealant films.

By including one or more sealant films, the laminated film can significantly block gas or liquid components such as odor, oxygen, water, and water vapor. In addition, the laminated film, including the sealant film, has excellent heat sealing strength even when heat-sealed at low temperatures, so it can not only have mechanical strength and optical properties, but also maintain excellent heat resistance, making it useful as a retort food flexible packaging material. You can use it.

As an embodiment, the laminated film may be heat-sealed by placing a sealant film on one or both sides of the substrate.

The substrate may be obtained by laminating and heat-pressing any one or two or more materials selected from a printed film, base film, barrier film, and printed barrier film. The laminated film can have excellent gas barrier properties and water vapor barrier properties by having a sealant film disposed on one or both sides, and can have excellent mechanical properties and excellent transparency, so it can be usefully used as a flexible packaging material.

As an example, the laminated film may be a lamination of two or more sealant films manufactured including a low-temperature heat-sealable resin composition, including the sealant film (A), an impact-resistant polypropylene film (B), and a heat-resistant polypropylene film. It may be manufactured by laminating (C) and another thermoplastic film (D).

The configuration of the laminated film is not limited, but as a non-limiting example, it may be laminated and heat-sealed in various structures such as A-B, A-B-C, A-B-C-D, A-B-C-B-C, or A-B-C-B-A.

Even when the laminated film uses a biaxially oriented polypropylene film (BOPP) as a base film, the sealant film not only allows heat sealing at low temperatures, but also has excellent heat sealing strength even when heat sealing at low temperatures, thereby providing excellent mechanical strength. and may have excellent optical properties.

As an embodiment, the laminated film may have a haze measured by ASTM D1003 of 5% or less, specifically 4% or less, 3% or less, and more specifically 2.8% or less, 2.7% or less, and 2.5% or less. It may be 2.4% or less, 2.3% or less, and may also be 1.8 to 2.2%.

Since the laminated film is manufactured including a sealant film manufactured including a low-temperature heat-sealable resin composition, there is no problem of the surface becoming rough or wrinkles due to heat shrinkage, and the haze within the above range can be satisfied. In addition, the laminated film has excellent bleeding resistance of the sealant film included in it, so it does not transfer to the surface even if left for a long period of time, making it possible to maintain the haze in the above range for a long period of time.

As an embodiment, the laminated film may have a MD (Machine direction stretcher) breaking strength of 150 to 200 kg/cm3 and a TD (Transverse direction stretcher) breaking strength of 120 to 150 kg/cm3, as measured by ASTM D882. .

Specifically, the MD breaking strength of the laminated film may be 160 to 200 kg/cm3, and more specifically, 170 to 200 kg/cm3. Additionally, specifically, the TD breaking strength of the laminated film may be 130 to 150 kg/cm3, and more specifically, 140 to 150 kg/cm3.

As another embodiment, the laminated film may have a MD elongation at break of 500 to 600% and a TD elongation at break of 600 to 700%, as measured by ASTM D882. Specifically, the MD elongation of the laminated film may be 530 to 600%, and more specifically, 550 to 600%. Additionally, specifically, the TD elongation of the laminated film may be 620 to 680%, and more specifically, may be 640 to 680%.

When a laminated film having a tensile strength at break and an elongation at break in the above range is used as a flexible packaging material, it can be preferred because it can prevent the packaged material from being damaged by external shock.

As an embodiment, the laminated film has the above breaking strength and elongation at break, so the 100% modulus of MD as measured by ASTM D882 may be 50 to 100 kg/cm3, and the 100% modulus of TD may be 20 to 80 kg. It can be /㎤.

Specifically, the laminated film may have a 100% MD modulus of 60 to 90 kg/cm3, and more specifically, 70 to 80 kg/cm3. Additionally, the laminated film may have a 100% TD modulus of 20 to 60 kg/cm3, and more specifically, 30 to 50 kg/cm3.

A laminated film having a modulus of 100% of the above range has a high elastic modulus, has high flexibility, and can have the excellent impact strength described below.

As one embodiment, the laminated film may have an impact strength measured by ASTM D1709 A of 200 to 500 g, specifically 250 to 400 g, and more specifically 300 to 400 g.

A laminated film with an impact strength in the above range has excellent impact resistance, and the incidence of damage due to external impact is greatly reduced, so when used as a flexible packaging material, it can prevent damage, contamination, and oxidation of packaged food. may be preferred.

In other words, the laminated film is manufactured by including one or more sealant films manufactured including a low-temperature heat-sealable resin composition, so that not only low-temperature heat-sealing is possible even when recyclable BOPP is used as the base film, but also excellent low-temperature heat sealing properties. It can maintain sealing strength and excellent heat resistance. In addition, the laminated film can have the above-mentioned heat sealing strength and heat resistance while also having excellent mechanical strength and transparency, so it can be usefully used as a flexible packaging material.

Through the following examples, the low-temperature heat-sealable resin composition and the sealant film and laminated film manufactured including the same will be described in more detail. However, the following examples are only a reference for explaining the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms. Additionally, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. Additionally, the terms used in the description in the present invention are only intended to effectively describe specific embodiments and are not intended to limit the present invention.

[measurement method]

1. Melt flow rate test

Measured according to ASTM D1238, 190°C. The resin was melted at 210°C or 230°C and pressure was applied with a load of 2.16 kg for measurement.

2. Heat seal strength test

Measured according to ASTM F88, using a standard heat seal gradient tester (Toyo Seiki, heat seal gradient tester) at 2 atm for 1.5 seconds at 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃, 150 ℃ or Measurement samples were prepared by heat sealing at 160°C. Afterwards, the heat seal strength of the prepared measurement sample was measured using a tensile strength test device (Daekyung Engineering, tensile compression tester). At this time, if the measurement sample is torn rather than peeled during measurement, it is indicated as F.

3. Measurement of bridging resistance

The films prepared in the following Examples and Comparative Examples were made into measurement samples of 2*4 cm, oiled paper was attached to both sides of the measurement sample, overlapped in the form of a sandwich, and then pressed for 48 hours with a 1kg load at room temperature, and then the oiled paper was removed from the surface. The amount transferred internally was measured and compared relatively. At this time, the amount transferred was calculated using Equation 1 below.

[Equation 1]

Amount of fatty acid amide compound transferred (△E) = [(E ₁ -E ₂ )/E ₁ ] × 100

In equation 1 above,

E ₁ is the weight of the initial measurement sample,

E ₂ is the weight of the sample measured after pressing for 48 hours at room temperature and removing the fatty acid amide compound that migrates to the surface.

4. Haze measurement

According to ASTM D1003, the Haze value was measured using a Haze METER (NIPPON DENSHOKU, NDH 5000).

5. 100% modulus measurement

Samples were manufactured and measured in accordance with ASTM D882, using a measuring device (INSTRON). The 100% modulus of the sample was measured.

6. Impact strength measurement (Dart impact strength)

Samples were manufactured and measured according to ASTM D1709A, and the impact resistance of the samples was measured using a measuring device (INSTRON).

[Production Examples 1 to 3]

Polypropylene (A-1), ethylene-methyl methacrylate copolymer (C-1), Erucamide (D-1), and Ethylene-bis-Oleamide (D-) having the melting points and melt flow indices shown in Table 1 below. 2) and nano silica particles (E-1, average particle size: 5 ㎛, Microd, KD Coporation).

Afterwards, the above ingredients were kneaded at a cylinder temperature of 220°C using a twin-screw extruder (32Φ, L/D=36, SM PLATEK) with the composition shown in Table 2 below, and then pelletized to produce a masterbatch.

ingredient Resin type melting point
(℃) density
(g/㎤) melt flow index
(g/10min) 190℃ 230℃ A-1 polypropylene 152 0.900 - 3.5 A-2 Propylene-ethylene copolymer 140 0.900 - 1.8 A-3 Propylene-ethylene-butylene copolymer 130 0.900 - 7.0 B-1 Butylene-propylene copolymer 58 0.880 4.0 - B-2 Propylene-ethylene copolymer - 0.862 1.4 3.0 C-1 Ethylene-methyl methacrylate copolymer 92 0.940 3.0 - D-1 Erucamide 81 0.874 - - D-2 Ethylene-bis-Oleamide 118 0.899 - -

(weight%) A-1 C-1 D-1 D-2 E-1 Manufacturing Example 1 50 30 10 - 10 Production example 2 - 80 - 10 10 Production example 3 80 - 10 - 10

[Example 1]

Propylene-ethylene copolymer (A-2) and propylene-butylene copolymer (B-1) having the density, melting point, and melt flow index shown in Table 1 were used.

Afterwards, 70% by weight of the propylene-ethylene copolymer (A-2), 25% by weight of the propylene-butylene copolymer (B-1), and 5% by weight of the masterbatch of Preparation Example 1 were melted and mixed at 220°C. A low-temperature heat-sealable resin composition of the composition shown in Table 3 below was prepared. The manufactured low-temperature heat-sealable resin composition was molded in T-Die to produce a sealant film.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Example 2]

In Example 2, a sealant film was prepared in the same manner as the masterbatch of Preparation Example 1 except that 5% by weight of the masterbatch prepared in Preparation Example 2 was used.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Example 3]

Propylpropylene-ethylene-butylene copolymer (A-3) and propylene-butylene copolymer (B-1) having the density, melting point, and melt flow index shown in Table 1 were used.

Afterwards, 70% by weight of the propylpropylene-ethylene-butylene copolymer (A-3), 25% by weight of the propylene-butylene copolymer (B-1), 2.5% by weight of the masterbatch of Preparation Example 1, and the master of Preparation Example 2. A low-temperature heat-sealable resin composition having the composition shown in Table 3 below was prepared by melting and mixing 2.5% by weight of the batch at 220°C. Afterwards, the prepared low-temperature heat-sealable resin composition was molded in a T-Die to produce a sealant film.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Example 4]

A sealant film was prepared in the same manner as in Example 3, except that 5% by weight of the masterbatch prepared in Preparation Example 1 was used.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Example 5]

A sealant film was prepared in the same manner as in Example 3, except that 5% by weight of the masterbatch prepared in Preparation Example 2 was used.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Comparative Examples 1 to 4]

Propylene-ethylene copolymer (A-2), propylene-ethylene-butylene copolymer (A-3), and propylene-butylene copolymer (B-1) having the density, melting point, and melt flow index shown in Table 1 above. ) was used.

Thereafter, the composition shown in Table 3 below was melted and mixed at 220°C, and after the melting and mixing was completed, the melted low-temperature heat-sealable resin composition was molded in a T-Die to prepare a sealant film.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Comparative Example 5]

A sealant film was prepared in the same manner as in Example 1, except that 95% by weight of propylene-ethylene copolymer (A-2) was used instead of propylene-butylene copolymer (B-1).

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Comparative Example 6]

In Example 1, propylene-butylene copolymer (B-1) was not used, but 25% by weight of propylene-ethylene (B-2) having the density, melting point, and melt flow index shown in Table 1 was used. The sealant film was manufactured in the same manner except that.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

[Comparative Example 7]

In Example 3, a sealant film was prepared in the same manner, except that 5% by weight of the master batch prepared in Preparation Example 3 was used as the master batch.

Afterwards, the prepared sealant film was measured using the above measurement method and is shown in Table 4 below.

(weight%) A-1 A-2 A-3 B-1 B-2 C-1 D-1 D-2 E-1 Example 1 2.5 70 - 25 - 1.5 0.5 - 0.5 Example 2 - 70 - 25 - 4 0.5 0.5 Example 3 1.25 - 70 25 - 2.75 0.25 0.25 0.5 Example 4 2.5 - 70 25 - 1.5 0.5 - 0.5 Example 5 - - 70 25 - 4 0.5 0.5 Comparative Example 1 - 100 - - - - - - - Comparative Example 2 - - 100 - - - - - 　 Comparative Example 3 -　 75 - 25 - - - - - Comparative Example 4 - - 75 25 - - - - - Comparative Example 5 2.5 95 - - - 1.5 0.5 - 0.5 Comparative Example 6 2.5 70 - -　 25 1.5 0.5 - 0.5 Comparative Example 7 4 - 70 25 - - 0.5 - 0.5 A-1: Polypropylene
A-2: Propylene-ethylene copolymer
A-3: Propylene-ethylene-butylene copolymer
B-1: Propylene-butylene copolymer
B-2: Propylene-ethylene copolymer
C-1: Ethylene-methyl methacrylate copolymer
D-1: Ericamide
D-2: Ethylene-bis-Oleamide
E-1: Nano silica particles

heat seal strength
(g/25㎜) Breeding ability
(△E) 100℃ 110℃ 120℃ 130℃ 140℃ 150℃ 160℃ Example 1 203 481 689 897 1,049 2,110 F 0.05 Example 2 256 640 791 1,241 1,690 F F 0 Example 3 251 1,140 1,552 2,100 F F F 0.02 Example 4 150 875 1,796 2,104 F F F 0.05 Example 5 377 1,402 2,100 F F F F 0 Comparative Example 1 0 0 0 0 0 139 F - Comparative Example 2 0 0 15 1,557 1,811 F F - Comparative Example 3 0 0 0 102 228 1,927 F - Comparative Example 4 42 153 1,441 1,843 1,892 F F - Comparative Example 5 0 0 125 205 332 454 2,956 0.05 Comparative Example 6 0 26 1,839 2,179 F F F 0.05 Comparative Example 7 45 175 1,666 1,932 F F F 0.68

Looking at Table 4, it was confirmed that Examples 1 to 5 were capable of heat sealing at low temperatures of 100 ℃ and 110 ℃ and had excellent heat sealing strength of 150 g / 25 mm or more at 100 ℃ and 110 ℃, but Comparative Example It was confirmed that Nos. 1 to 7 cannot be heat-sealed at 100°C and 110°C, and even if heat-sealed at 100°C, they have a very low heat-sealing strength of less than 50 g/25mm.

In addition, when the bleeding resistance is confirmed in Table 3, Examples 1 to 5 have very excellent bleeding resistance, as the amount of fatty acid amide compounds migrated to the surface is 0.05 or less, but in Comparative Example 7, the amount of fatty acid amide compounds migrated to the surface is 0.68. It was confirmed to have very low breeding resistance.

That is, the sealant film manufactured including the low-temperature heat-sealable resin composition according to one embodiment of the present invention is not only capable of heat-sealing at low temperatures, but also has excellent heat-sealing strength even when heat-sealing at low temperatures, and has excellent bleed resistance. By having it, excellent physical properties can be maintained for a long period of time.

[Example 6]

A polymer having the density, melting point, and melt flow index shown in Table 1 was used. Using multi-layer blown film manufacturing equipment (Modern Machinery Co., Ltd., Water cooled blown film machine) equipped with 5 extruders, polypropylene (A-1) was added to the first layer, and propylene was added to the second to fourth layers. -75% by weight of ethylene-butylene copolymer (A-3) and 25% by weight of propylene-ethylene copolymer (B-1) were mixed and added, and the low-temperature heat-sealable resin composition of Example 4 was added to the fifth layer. was added to produce a laminated film. At this time, the temperature of the extruder was 200°C, and the die temperature was maintained at 215°C.

Thereafter, the manufactured laminated film was measured using the above measurement method and is shown in Tables 5 and 6 below.

[Comparative Example 8]

In Example 6, propylene-ethylene copolymer (A-2) was added alone to the second to fourth layers, and propylene-ethylene-butylene copolymer (A-3) was added alone to the fifth layer. The laminated film was manufactured in the same manner except that.

Thereafter, the manufactured laminated film was measured using the above measurement method and is shown in Tables 5 and 6 below.

Heat seal strength (g/25mm) 100℃ 110℃ 120℃ 130℃ 140℃ 150℃ Example 6 217 389 831 3,707 4,275 4,281 Comparative Example 8 0 0 19 3,489 3,447 3,487

Haze
(%) Dart impact strength
(g) 100% modulus
(kg/㎤) M.D. TD Example 6 2.1 306 73 34 Comparative Example 8 3.0 111 90 78

Checking Table 5, it was confirmed that Example 6 was not only capable of heat sealing at low temperatures, but also had a heat sealing strength of 217 g/25 mm even when heat sealed at 100°C, but Comparative Example 8 was 100°C and 110°C. It was confirmed that it was not heat-sealed at ℃, and even when heat-sealed at 120 ℃, the heat-sealing strength was very low at 19 g/25mm.

Additionally, looking at Table 6 above, it was confirmed that Example 6 had superior transparency and mechanical strength than Comparative Example 8.

Therefore, the sealant film manufactured including the low-temperature heat-sealable resin composition can be heat-sealed at low temperatures and can have excellent heat-sealing strength even when heat-sealed at low temperatures, and the laminated film manufactured including the sealant film It has excellent heat-sealing strength even when heat-sealed at low temperatures, and has excellent thermal, optical, and mechanical properties, so it can be usefully used as a flexible packaging material that requires heat resistance and mechanical properties.

As described above, the present invention has been described with specific details and limited examples and comparative examples, but these are provided only to facilitate a more general understanding of the present invention, and the present invention is not limited to the above examples. Those skilled in the art can make various modifications and variations from this description. Accordingly, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described later as well as all things that are equivalent or equivalent to the scope of this patent claim shall fall within the scope of the spirit of the present invention. .

Claims (15)

(a) propylene-based polymer;
(b) propylene-butylene copolymer;
(c) (meth)acrylate-based copolymer; and
(d) A low-temperature heat-sealable resin composition comprising a fatty acid amide compound. According to clause 1,
The propylene-based polymer; is a low-temperature heat-sealable resin composition comprising any one or two or more selected from propylene homopolymer, propylene-ethylene copolymer, and propylene-ethylene-butylene copolymer. According to clause 1,
The propylene-butylene copolymer; is a low-temperature heat-sealable resin composition comprising 50 mol% or more of butylene repeating units based on the total repeating units. According to clause 1,
The low-temperature heat-sealable resin composition includes 10 to 30% by weight of a propylene-butylene copolymer. According to clause 1,
The (meth)acrylate-based copolymer; is a low-temperature heat-sealable resin composition that is a copolymerization of C ₁ -C ₆ alkyl (meth)acrylate and one or two or more selected from ethylene, propylene, and butylene. According to clause 1,
The low-temperature heat-sealable resin composition includes 1 to 10% by weight of a (meth)acrylate-based copolymer. According to clause 1,
The fatty acid amide compound; is a low-temperature heat-sealable resin composition comprising one or two or more selected from oleic acid amide, erucamide, ethylene-bis-oleamide, behenamide, and ethylene-bis-steamide. According to clause 1,
The low-temperature heat-sealable resin composition includes 0.1 to 1% by weight of a fatty acid amamide compound. According to clause 1,
The low-temperature heat-sealable resin composition further includes one or more additives selected from the group consisting of plasticizers, lubricants, stabilizers, viscosity regulators, processing aids, flame retardants, enhancers, and dispersants. According to clause 1,
The low-temperature heat-sealable resin composition is a fatty acid amide compound, wherein the transferred amount (ΔE) satisfies the following formula 1:
[Equation 1]
Transferred amount of fatty acid amide compound (△E) = [(E ₁ -E ₂ )/E ₁ ]≤0.05
(In Equation 1 above,
E ₁ is the weight of the initial measurement sample,
E ₂ is the weight of the specimen measured at room temperature for 48 hours with the fatty acid amide compound transferred to the surface removed.) According to clause 1,
The low-temperature heat-sealable resin composition is heat-sealed at 100°C and has a heat-sealing strength of 150 to 500 g/25mm as measured by ASTM F88. According to clause 1,
The low-temperature heat-sealable resin composition is heat-sealed at 110°C and has a heat-sealing strength of 450 to 1,500 g/25mm as measured by ASTM F88. A sealant film manufactured comprising the low-temperature heat-sealable resin composition of any one of claims 1 to 12. A heat-sealed laminated film comprising at least one sealant film of claim 13. According to clause 14,
The laminated film has a haze of 5% or less as measured by ASTM D1003.