Waterproof and moisture-permeable film

Abstract

One aspect of the present invention provides a waterproof and moisture-permeable film comprising a porous film having: a hydrophobic region containing a polyolefin; and hydrophilic regions containing a hydrophilic polymer and a hydrophilic inorganic material and distributed in the hydrophobic region, wherein the amount of the hydrophilic polymer contained in the porous film is 0.1-30 wt%.

Description

Waterproof and moisture-permeable film

[0001] The present invention relates to a moisture-permeable waterproof film, and more particularly, to a moisture-permeable waterproof film capable of alleviating the trade-off between moisture-permeable waterproofness, durability, and mechanical properties, thereby achieving and improving them in a balanced manner.

[0002] Clothing, shoes, gloves, hats, and other items often include a breathable and waterproof layer, or "water-permeable waterproof layer," which can keep the wearer dry in humid conditions and provide a comfortable wearing experience. Specifically, the water-permeable waterproof layer allows moisture vapor, such as sweat, inside the garment to pass through and out, while preventing external moisture from penetrating inside the garment. This prevents the garment from getting wet from rain or snow (waterproof) and allows sweat to pass through (breathable), helping the wearer regulate their body temperature and maintain comfort. With the recent increase in interest in health and leisure activities, fabrics containing water-permeable waterproof layers are being applied in a variety of fields.

[0003] The electrospun nanofiber web used as a moisture-permeable waterproof layer has problems such as lower mechanical properties such as strength compared to conventional film-type fabrics because the nanofibers are not fixed, and low durability such as easy peeling or scratching occurs. In response to this, a moisture-permeable waterproof fabric coated with a liquid adhesive and a nanofiber web bonded by heat compression are known. However, there are problems such as the liquid adhesive reducing and / or closing the pores of the fabric and nanofiber web, which reduces moisture permeability, and the uneven application of the liquid adhesive lowers moisture permeability efficiency. In addition, attempts are being made to improve scratch resistance and durability by coating the nanofiber web with a hydrophilic polymer such as polyurethane. However, even in this case, the original advantages of the nanofiber web such as breathability, moisture permeability, lightness, softness, and feel are reduced, and noise is generated or increases when bending and / or friction is performed.

[0004] GORE-TEX is a representative waterproof and breathable fabric, and is a waterproof and breathable film manufactured using a microporous PTFE membrane and hydrophilic polyurethane. ® It is used to manufacture fabric laminates. The pore size of the PTFE membrane is larger than that of a water molecule, but the pores are much smaller than individual water droplets, so water vapor can pass through the membrane, but water droplets cannot. However, GORE-TEX ® Fluorinated resins, the main raw material for fabrics, are expensive, heavy, and, particularly, harmful to humans and the surrounding environment. Therefore, regulations are being strengthened. To address this issue, plasma irradiation has been used to impart water repellency to only one side of non-fluorinated fabrics, such as polyester. However, plasma treatment increases the material's brittleness, drastically reducing its durability and reducing moisture permeability, resulting in discomfort for the wearer.

[0005] The present invention is intended to solve the problems of the prior art described above, and the purpose of the present invention is to provide a moisture-permeable and waterproof film that can implement and improve moisture-permeable and waterproof properties in a balanced manner by alleviating the trade-off between moisture-permeable and waterproof properties, durability, and mechanical properties.

[0006] One aspect of the present invention provides a moisture-permeable and waterproof film comprising a porous film having a hydrophobic region including polyolefin; and a hydrophilic region including a hydrophilic polymer and a hydrophilic inorganic material dispersed in the hydrophobic region; wherein the content of the hydrophilic polymer in the porous film is 0.1 to 30 wt%.

[0007] In one embodiment, the content of the hydrophilic inorganic material in the porous film may be 0.1 to 30 wt%.

[0008] In one embodiment, the content of the hydrophilic region in the porous film may be 0.1 to 60 wt%.

[0009] In one embodiment, the weight average molecular weight of the polyolefin may be 200,000 to 800,000, the content of the hydrophilic polymer in the porous film may be 0.1 to 25 wt%, the content of the hydrophilic inorganic material in the porous film may be 0.1 to 25 wt%, and the content of the hydrophilic region in the porous film may be 0.2 to 45 wt%.

[0010] In one embodiment, the weight average molecular weight of the polyolefin may be 900,000 to 2,000,000, the content of the hydrophilic polymer in the porous film may be 25 to 30 wt%, the content of the hydrophilic inorganic material in the porous film may be 25 to 30 wt%, and the content of the hydrophilic region in the porous film may be 45 to 60 wt%.

[0011] In one embodiment, the polyolefin may include one selected from the group consisting of polyethylene, polypropylene, polybutylene, polymethylpentene, and combinations of two or more thereof.

[0012] In one embodiment, the hydrophilic polymer may include one selected from the group consisting of ethylene vinyl acetate, ethylene vinyl alcohol, polyvinyl alcohol, polyacrylic acid, polyoxyethylene-polyoxypropylene block copolymer, polyethylene glycol, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl acetal, polyvinyl butyral, cellulose derivatives, polyurethane, polyamide, polyester, glycerol, and combinations of two or more thereof.

[0013] In one embodiment, the hydrophilic inorganic material may include one selected from the group consisting of SiO2, AlO(OH), Mg(OH)2, Al(OH)3, TiO2, BaTiO3, Li2O, LiF, LiOH, Li3N, BaO, Na2O, Li2CO3, CaCO3, LiAlO2, Al2O3, SiO, SnO, SnO2, PbO2, ZnO, P2O5, CuO, MoO, V2O5, B2O3, Si3N4, CeO2, Mn3O4, Sn2P2O7, Sn2B2O5, Sn2BPO6, talc, and combinations of two or more thereof.

[0014] In one embodiment, the porosity of the porous film may be 60 to 90 volume%.

[0015] In one embodiment, the average pore size of the porous film may be 100 to 200 nm.

[0016] In one embodiment, the change in length in the longitudinal direction (MD) may be 20 to 50% and the change in length in the transverse direction (TD) may be 20 to 50% from immediately after the addition of a water droplet to the surface of the porous film until 5 minutes have elapsed.

[0017] In one embodiment, the water vapor transmission rate (MVTR) of the porous film measured according to EN ISO 15496 is 5,000 to 20,000 g / m 2 / It can be 24hrs.

[0018] In one embodiment, the porous film may satisfy at least one of the conditions (i) to (iv) below.

[0019] (i) Thickness 1~30㎛, (ii) Puncture strength 500gf or more, (iii) Longitudinal (MD) tensile strength 1,000~3,000kgf / cm 2 , (iv) Transverse direction (TD) tensile strength 1,000~3,000 kgf / cm 2 .

[0020] Another aspect of the present invention provides a laminated article comprising: the moisture-permeable and waterproof film; and at least one layer bonded to the moisture-permeable and waterproof film.

[0021] In one embodiment, the layer may include one selected from the group consisting of a textile layer, a polymer film layer, a natural leather layer, a synthetic leather layer, a fleece layer, and a combination of two or more thereof.

[0022] A moisture-permeable and waterproof film according to one aspect of the present invention is composed of a porous film having a hydrophobic region including polyolefin; and a hydrophilic region including a hydrophilic polymer and a hydrophilic inorganic substance dispersed in the hydrophobic region; wherein, by controlling the contents of the hydrophilic polymer, the hydrophilic inorganic substance, and the hydrophilic region including them in the porous film, the weight average molecular weight of the polyolefin, etc., the trade-off among moisture-permeable and waterproof properties, durability, and mechanical properties can be alleviated, thereby implementing and improving them in a balanced manner.

[0023] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the composition of the invention described in the claims.

[0024] The present invention will be described below. However, the present invention may be implemented in various different forms and is therefore not limited to the embodiments described herein.

[0025] Throughout the specification, when a part is said to be "connected" to another part, this includes not only "directly connected" but also "indirectly connected" with other elements intervening. Furthermore, when a part is said to "include" a component, this does not exclude other components, but rather implies that the other components may be included, unless otherwise specifically stated.

[0026] One aspect of the present invention provides a moisture-permeable and waterproof film comprising a porous film having a hydrophobic region including polyolefin; and a hydrophilic region including a hydrophilic polymer and a hydrophilic inorganic material dispersed in the hydrophobic region; wherein the content of the hydrophilic polymer in the porous film is 0.1 to 30 wt%.

[0027] In the above porous film, the hydrophobic region and the hydrophilic region may constitute a continuous phase and a discontinuous phase, respectively. Since the hydrophobic region has a high surface tension when in contact with moisture, it can lower the wettability of the film with respect to moisture, thereby imparting a necessary level of waterproofness to the film. The hydrophilic region can be uniformly dispersed in a matrix composed of the hydrophobic regions, thereby imparting substantially uniform hydrophilicity to the entire area and / or thickness direction of the porous film, thereby contributing to securing the affinity for moisture of the porous film and the moisture permeability thereof.

[0028] Among the hydrophilic regions, the hydrophilic polymer has a low surface tension when in contact with moisture, so it can contribute to imparting moisture permeability to the film by increasing the wettability of the film with respect to moisture, and the hydrophilic inorganic material not only has an affinity for moisture, but also has hygroscopicity and / or absorbency to absorb moisture existing around the porous film and induce or maintain a dry state, so it can contribute to imparting moisture permeability to the film by increasing the wettability of the film with respect to moisture together with the hydrophilic polymer.

[0029] The term "matrix" as used herein refers to a component forming a continuous phase in a film comprising two or more components. That is, in the porous film, the hydrophobic region comprising the polyolefin may exist as a continuous phase, and within the porous film, the hydrophobic region comprising the hydrophilic polymer may exist dispersed as a discontinuous phase.

[0030] The content of the hydrophilic polymer in the porous film may be 0.1 to 30 wt%. If the content of the hydrophilic polymer is 0.1 wt%, the required level of hydrophilicity and the resulting moisture permeability cannot be achieved. If the content exceeds 30 wt%, the hydrophilicity and moisture permeability may be further improved, but the mechanical properties of the film, particularly the tensile strength and puncture strength, which can be achieved through the hydrophobic region including the polyolefin, may deteriorate. In addition, if the content of the hydrophilic polymer exceeds 30 wt%, the dispersibility of the hydrophilic polymer deteriorates, so that the number of surface defects having a different brightness from the surroundings and a size of 2 mm or more on the surface of the porous film increases, which may deteriorate the appearance quality. In addition, moisture permeability, waterproofness, and mechanical properties may suddenly change in a portion and / or region where the hydrophilic polymer is randomly aggregated on the surface and / or inside of the porous film, which may deteriorate the reproducibility and reliability of the film.

[0031] The hydrophilic polymer may include, for example, one selected from the group consisting of ethylene vinyl acetate, ethylene vinyl alcohol, polyvinyl alcohol, polyacrylic acid, polyoxyethylene-polyoxypropylene block copolymer, polyethylene glycol, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl acetal, polyvinyl butyral, cellulose derivatives, polyurethane, polyamide, polyester, glycerol, and combinations of two or more thereof, preferably, ethylene vinyl acetate, and more preferably, ethylene vinyl acetate having a vinyl acetate content of 15 to 30 wt%, but is not limited thereto. If the vinyl acetate content in the ethylene vinyl acetate is less than 15 wt%, the mechanical properties and hydrophilicity of the film may deteriorate, and if it exceeds 30 wt%, the processability and the dispersibility of the hydrophilic polymer may deteriorate accordingly. Meanwhile, as the hydrophilic polymer, in addition to those described above, various types of hydrophilic polymers having hydrophilic functional groups such as amine groups, amide groups, hydroxyl groups, and carboxylic acid groups in the main chain and / or side chain may be applied.

[0032] The content of the hydrophilic inorganic material in the porous film may be 0.1 to 30 wt%. If the content of the hydrophilic inorganic material is 0.1 wt%, the required level of hydrophilicity and the resulting moisture permeability cannot be achieved. If the content exceeds 30 wt%, the hydrophilicity and moisture permeability may be further improved, but the mechanical properties of the film, particularly the tensile strength and puncture strength, which can be achieved through the hydrophobic region including the polyolefin, may be reduced. In addition, if the content of the hydrophilic inorganic material exceeds 30 wt%, the dispersibility of the hydrophilic inorganic material is reduced, so that the number of surface defects having a different brightness from the surroundings and a size of 2 mm or more on the surface of the porous film increases, which may lower the appearance quality. In addition, moisture permeability, waterproofness, and mechanical properties may suddenly change in a portion and / or region where the hydrophilic inorganic material is randomly aggregated on the surface and / or inside of the porous film, which may lower the reproducibility and reliability of the film.

[0033] The hydrophilic inorganic material may include, for example, one selected from the group consisting of SiO2, AlO(OH), Mg(OH)2, Al(OH)3, TiO2, BaTiO3, Li2O, LiF, LiOH, Li3N, BaO, Na2O, Li2CO3, CaCO3, LiAlO2, Al2O3, SiO, SnO, SnO2, PbO2, ZnO, P2O5, CuO, MoO, V2O5, B2O3, Si3N4, CeO2, Mn3O4, Sn2P2O7, Sn2B2O5, Sn2BPO6, talc, and a combination of two or more thereof, and preferably may include SiO2, and more preferably may include fumed SiO2, but is not limited thereto. Meanwhile, in addition to the hydrophilic inorganic substances described above, those in which the surface of the hydrophilic inorganic substance, which is mainly present in the form of particles, is modified with a functional group having an affinity for the hydrophilic polymer and / or the polyolefin may also be applied.

[0034] The content of the hydrophilic region including the hydrophilic polymer and the hydrophilic inorganic material in the porous film may be 0.1 to 60 wt%. In other words, the total content of the hydrophilic polymer and the hydrophilic inorganic material in the porous film may be 0.1 to 60 wt%. If the content of the hydrophilic region is 0.1 wt%, the required level of hydrophilicity and the corresponding moisture permeability cannot be implemented, and if it exceeds 60 wt%, the hydrophilicity and moisture permeability can be further improved, but the mechanical properties of the film that can be implemented through the hydrophobic region including the polyolefin, particularly, the tensile strength and puncture strength, are lowered, and there is a problem that the required level of waterproofness cannot be implemented. In addition, if the content of the hydrophilic region exceeds 60 wt%, the dispersibility of the hydrophilic region is reduced, so that the number of surface defects having a different brightness from the surroundings and a size of 2 mm or more on the surface of the porous film increases, which may deteriorate the appearance quality, and in the area and / or region where the hydrophilic region is randomly aggregated on the surface and / or inside of the porous film, moisture permeability, waterproofness, and mechanical properties may rapidly change, which may deteriorate the reproducibility and reliability of the film.

[0035] The polyolefin may include one selected from the group consisting of polyethylene, polypropylene, polybutylene, polymethylpentene, and combinations of two or more thereof, preferably, at least one of polyethylene and polypropylene, and more preferably, polyethylene, but is not limited thereto.

[0036] Conventionally, porous films made solely of polyolefin are inherently hydrophobic, but by melting and mixing the polyolefin with a certain amount of a hydrophilic polymer and / or a hydrophilic inorganic substance during film production, a desired hydrophilicity can be imparted to the film. In this case, by deriving and combining the molecular weight of the polyolefin and the content of the hydrophilic polymer and / or the hydrophilic inorganic substance in the film as variables that optimize and implement the required levels of moisture permeability, waterproofness, and mechanical properties, the productivity of the process for melting and mixing the hydrophilic polymer and / or the hydrophilic inorganic substance with the polyolefin, and the moisture permeability, waterproofness, and mechanical properties of the film can be implemented in a balanced manner.

[0037] First, when the polyolefin includes high-density polyethylene (HDPE), the weight average molecular weight of the high-density polyethylene may be 200,000 to 800,000, preferably 250,000 to 600,000, more preferably 300,000 to 600,000, the content of the hydrophilic polymer in the porous film may be 0.1 to 25 wt%, 1 to 20 wt%, 5 to 20 wt%, 10 to 20 wt%, the content of the hydrophilic inorganic material in the porous film may be 0.1 to 25 wt%, 1 to 20 wt%, 5 to 20 wt%, 10 to 20 wt%, and the content of the hydrophilic region in the porous film may be 0.2 to 45 wt%, 10 to 40 wt%, 20 to 40 wt%, 20 to 35 wt%. The term "weight average molecular weight" used in this specification may mean a value measured by gel permeation chromatography (GPC) using polystyrene as a standard sample according to the method described in the literature (Macromolecules, Vol. 34, No. 19, pp. 6812-6820 (2001), etc.).

[0038] If the content of the hydrophilic polymer in the porous film is less than 0.1 wt%, the required level of hydrophilicity and the resulting moisture permeability cannot be achieved, and if it exceeds 25 wt%, the content of the high-density polyethylene is relatively reduced, so that the mechanical properties of the film that can be achieved through the hydrophobic region, particularly, tensile strength and puncture strength, may deteriorate. If the content of the hydrophilic inorganic material in the porous film is less than 0.1 wt%, the required level of hydrophilicity and the resulting moisture permeability cannot be achieved, and if it exceeds 25 wt%, the content of the high-density polyethylene is relatively reduced, so that the mechanical properties of the film that can be achieved through the hydrophobic region, particularly, tensile strength and puncture strength, may deteriorate. In addition, if the content of the hydrophilic region in the porous film is less than 0.2 wt%, the required level of hydrophilicity and moisture permeability cannot be achieved, and if it exceeds 45 wt%, the hydrophilicity and moisture permeability can be further improved, but the mechanical properties of the film that can be achieved through the hydrophobic region including the high-density polyethylene, particularly the tensile strength and puncture strength, are reduced, and the required level of waterproofness cannot be achieved, and the appearance quality may be deteriorated due to surface defects.

[0039] In this way, when the content of the hydrophilic region including the hydrophilic polymer and the hydrophilic inorganic material exceeds the upper limit, the hydrophilicity and moisture permeability of the film can be further improved, but the mechanical properties and waterproofness are deteriorated. In this case, the deteriorated mechanical properties and waterproofness can be effectively supplemented and reinforced by mixing high-density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE) as the polyolefin or replacing high-density polyethylene (HDPE) with ultra-high molecular weight polyethylene (UHMWPE).

[0040] When the polyolefin includes ultra-high molecular weight polyethylene, the content of the ultra-high molecular weight polyethylene in the hydrophobic region may be 20 to 100 wt%, preferably 30 to 100 wt%, and more preferably 50 to 100 wt%. When the content of the ultra-high molecular weight polyethylene in the hydrophobic region is less than 100 wt%, the remainder of the hydrophobic region may be composed of high-density polyethylene. When the content of the ultra-high molecular weight polyethylene in the hydrophobic region is less than 20 wt%, the mechanical properties and waterproofness that are deteriorated due to excessive application of the hydrophilic polymer and / or the hydrophilic inorganic material cannot be properly supplemented or reinforced.

[0041] The weight average molecular weight of the ultra-high molecular weight polyethylene may be 900,000 to 2,000,000, preferably 1,000,000 to 2,000,000, more preferably 1,200,000 to 2,000,000, the content of the hydrophilic polymer in the porous film may be 25 to 30 wt%, the content of the hydrophilic inorganic material in the porous film may be 25 to 30 wt%, and the content of the hydrophilic region in the porous film may be 45 to 60 wt%.

[0042] The porosity of the porous film may be 60 to 90 vol%, preferably 70 to 85 vol%, and more preferably 70 to 80 vol%. If the porosity of the porous film is less than 60 vol%, moisture permeability may be reduced, and if it is more than 90 vol%, waterproofness and mechanical properties, particularly tensile strength and puncture strength, may be reduced. The average pore size of the porous film may be 100 to 200 nm, preferably 110 to 180 nm, and more preferably 120 to 170 nm. If the average pore size of the porous film is less than 100 nm, moisture permeability may be reduced, and if it is more than 200 nm, waterproofness and mechanical properties, particularly tensile strength and puncture strength, may be reduced.

[0043] The change rate in the longitudinal direction (MD) length from immediately after the addition of the water droplet on the surface of the porous film to a time point after 5 minutes has elapsed may be 20 to 50%, preferably 25 to 50%, more preferably 30 to 45%, and the change rate in the transverse direction (TD) length may be 20 to 50%, preferably 25 to 50%, more preferably 30 to 45%. When the longest lengths in the longitudinal direction (MD) and transverse direction (TD) immediately after the addition of the water droplet on the surface of the porous film are MD1 and TD1, and the longest lengths in the longitudinal direction (MD) and transverse direction (TD) 5 minutes after the addition of the water droplet are MD2 and TD2, the length change rate can be calculated by the following Equations 1 and 2.

[0044] <Formula 1>

[0045] Change in length in the vertical direction (MD) (%) = (MD2-MD1) / (MD1) x 100

[0046] <Formula 2>

[0047] Transverse direction (TD) length change rate (%) = (TD2-TD1) / (TD1) x 100

[0048] The ratio of the longitudinal (MD) length change rate to the transverse (TD) length change rate of the water droplet may be 0.9 to 1.0, preferably 0.95 to 1.0. If the ratio of the longitudinal (MD) length change rate to the transverse (TD) length change rate of the water droplet is outside the above range, moisture permeation through the porous film may occur unevenly depending on the direction.

[0049] The water vapor transmission rate (MVTR) of the above porous film measured according to EN ISO 15496 is 5,000 to 20,000 g / m 2 / 24hr, preferably 8,000~20,000g / m 2 / 24hr, more preferably, 10,000~20,000g / m 2 / It can be 24hrs.

[0050] The above porous film can satisfy at least one of the conditions (i) to (iv) below.

[0051] (i) thickness of 1 to 30 μm, preferably 5 to 25 μm, more preferably 10 to 20 μm, (ii) puncture strength of 500 gf or more, preferably 500 to 1,000 gf, more preferably 700 to 1,000 gf, (iii) longitudinal (MD) tensile strength of 1,000 to 3,000 kgf / cm 2 , preferably 1,500~2,500kgf / cm 2 , more preferably, 1,500~2,000kgf / cm 2 , (iv) Transverse direction (TD) tensile strength 1,000~3,000 kgf / cm 2 , preferably 1,500~2,500kgf / cm 2 , more preferably, 1,500~2,000kgf / cm 2 .

[0052] The above moisture-permeable waterproof film can be manufactured by a method including: (a) a step of feeding a composition including polyolefin, a hydrophilic polymer, a hydrophilic inorganic material, and a pore-forming agent into an extruder and forming a base sheet; and (b) a step of stretching the base sheet and then extracting the pore-forming agent, or a step of extracting the pore-forming agent from the base sheet and then stretching it.

[0053] In the step (a), a composition including 10 to 30 wt% of the polyolefin, 0.1 to 10 wt% of the hydrophilic polymer, 0.1 to 10 wt% of the hydrophilic inorganic material, and the remainder of a pore-forming agent may be introduced into an extruder to form a base sheet. The types, physical properties, and effects of the polyolefin, the hydrophilic polymer, and the hydrophilic inorganic material are as described above. The input amounts of the polyolefin, the hydrophilic polymer, and the hydrophilic inorganic material may be adjusted so that the contents of the hydrophilic polymer and the hydrophilic inorganic material in the porous film are each 0.1 to 30 wt%, and the total content thereof is 0.1 to 60 wt%.

[0054] The above pore forming agent may be one selected from the group consisting of paraffin oil, paraffin wax, mineral oil, solid paraffin, soybean oil, rapeseed oil, palm oil, coconut oil, di-2-ethylhexyl phthalate, dibutyl phthalate, diisononyl phthalate, diisodecyl phthalate, bis(2-propylheptyl) phthalate, naphthene oil, and a combination of two or more thereof, preferably, paraffin oil, and more preferably, paraffin oil having a kinematic viscosity of 50 to 100 cSt at 40°C, but is not limited thereto.

[0055] In the step (b), a porous film can be obtained by stretching the base sheet and then extracting the pore-forming agent, or by extracting the pore-forming agent from the base sheet and then stretching it. The stretching can be performed by a known method such as uniaxial stretching or biaxial stretching (sequential or simultaneous). In the case of sequential biaxial stretching, the stretching ratio can be 4 to 20 times in the transverse direction (MD) and the longitudinal direction (TD), and the area magnification accordingly can be 16 to 400 times.

[0056] If necessary, the method may further include the step of (c) heat-setting the porous film obtained in step (b). Heat-setting is a process of fixing the film and applying heat to forcibly hold the film, which is about to shrink, to remove residual stress. A high heat-setting temperature is advantageous in reducing shrinkage, but if the temperature is excessively high, the film may partially melt, closing the formed pores, which may reduce moisture permeability. The heat-setting temperature is preferably selected within a range in which 10 to 30 wt% of the crystalline portion of the porous film melts. When the heat-setting temperature is selected within the above range, the problem of insufficient rearrangement of polyolefin molecules within the porous film, resulting in insufficient residual stress relief effect in the film, and the problem of partial melting, resulting in closure of pores, which may reduce moisture permeability, can be prevented. For example, the heat-setting temperature may be 120 to 150°C, preferably 130 to 145°C, and the heat-setting time may be 5 to 10 minutes, preferably 10 to 1 minute.

[0057] Meanwhile, a laminated article according to another aspect of the present invention may include the moisture-permeable and waterproof film; and at least one layer bonded to the moisture-permeable and waterproof film. The layer may include one selected from the group consisting of a textile layer, a polymer film layer, a natural leather layer, a synthetic leather layer, a fleece layer, and a combination of two or more thereof.

[0058] The laminated article may be a two-layer laminate comprising a textile layer adhered to at least one surface of the porous film. The laminated article may also be a three-layer laminate comprising a first textile layer adhered to one surface of the porous film and a second textile layer adhered to the other surface. In addition, other layers may be applied to produce a multi-layer laminate having four, five, six or more layers. The textile layer may include a woven fabric, a non-woven fabric, a knitted fabric, or the like. The textile layer may be natural and / or synthetic, for example, but is not limited to, cotton, wool, silk, jute, polyamide, polyester, acrylic, aramid, viscose, rayon, carbon fiber, or combinations thereof. The polymer film layer may be, for example, but is not limited to, polyolefin, polyester, polyamide, polyurethane, polyvinyl alcohol, polyvinyl acetate, fluoropolymer, polyvinyl halide, polyvinyl chloride, epoxy resin, silicone polymer, or a combination thereof.

[0059] Hereinafter, embodiments of the present invention will be described in detail.

[0060] 1. Content of ethylene vinyl acetate in the film

[0061] Example 1-1

[0062] 17.3 parts by weight of polyethylene (HDPE, PE1) having a weight average molecular weight (Mw) of 600,000, 7.5 parts by weight of ethylene vinyl acetate (EVA) having a vinyl acetate content of 28 wt%, 5 parts by weight of fumed silica, 0.2 parts by weight of antioxidant, and 70 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt at 40°C were mixed and fed into a twin-screw extruder (inner diameter 58 mm, L / D=56). Under the conditions of a screw rotation speed of 40 rpm and 200°C, the mixture was extruded from the twin-screw extruder through a T-Die having a width of 300 mm and then passed through a casting roll having a temperature of 40°C to produce a base sheet having a thickness of 800 μm.

[0063] The above base sheet was immersed in a dichloromethane leaching tank at 25°C to extract and remove paraffin oil for 1 minute, and then dried at 50°C for 5 minutes. The above base sheet was stretched 8 times in the longitudinal direction (MD) in a roll stretching machine at 110°C and 8 times in the transverse direction (TD) in a tenter stretching machine at 125°C to produce a porous film.

[0064] Example 1-2

[0065] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 18.8 parts by weight and 6 parts by weight, respectively.

[0066] Example 1-3

[0067] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 19.8 parts by weight and 5 parts by weight, respectively.

[0068] Example 1-4

[0069] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 21.8 parts by weight and 3 parts by weight, respectively.

[0070] Example 1-5

[0071] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 23.3 parts by weight and 1.5 parts by weight, respectively.

[0072] Example 1-6

[0073] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 24.5 parts by weight and 0.3 parts by weight, respectively.

[0074] Example 1-7

[0075] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 24.71 parts by weight and 0.09 parts by weight, respectively.

[0076] Example 1-8

[0077] 10.8 parts by weight of polyethylene (HDPE, PE1) having a weight average molecular weight (Mw) of 600,000, 5 parts by weight of polyethylene (UHMWPE, PE2) having a weight average molecular weight (Mw) of 2,000,000, 9 parts by weight of ethylene vinyl acetate (EVA) having a vinyl acetate content of 28 wt%, 5 parts by weight of fumed silica, 0.2 parts by weight of antioxidant, and 70 parts by weight of paraffin oil having a kinematic viscosity at 40°C of 70 cSt were mixed and fed into a twin-screw extruder (inner diameter 58 mm, L / D=56). Under the conditions of a screw rotation speed of 40 rpm and 200°C, the base sheet having a thickness of 800 μm was manufactured by extruding the material through a T-Die having a width of 300 mm from the twin-screw extruder and then passing it through a casting roll having a temperature of 40°C.

[0078] The above base sheet was immersed in a dichloromethane leaching tank at 25°C to extract and remove paraffin oil for 1 minute, and then dried at 50°C for 5 minutes. The base sheet was stretched 8 times in the longitudinal direction (MD) in a roll stretching machine at 110°C and 8 times in the transverse direction (TD) in a tenter stretching machine at 125°C to produce a porous film.

[0079] Example 1-9

[0080] A porous film was manufactured in the same manner as in Example 1-8, except that the input amounts of PE1, PE2, and EVA were changed to 5 parts by weight, 10.8 parts by weight, and 9 parts by weight, respectively.

[0081] Example 1-10

[0082] A porous film was manufactured in the same manner as in Example 1-8, except that PE1 was not used and the amounts of PE2 and EVA were changed to 15.8 parts by weight and 9 parts by weight, respectively.

[0083] Comparative Example 1-1

[0084] A porous film was manufactured in the same manner as in Example 1-1, except that EVA was not used and the amount of PE1 added was changed to 24.8 parts by weight.

[0085] Comparative Example 1-2

[0086] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 15.8 parts by weight and 9 parts by weight, respectively.

[0087] Comparative Example 1-3

[0088] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of PE1 and EVA were changed to 14.9 parts by weight and 9.9 parts by weight, respectively.

[0089] 2. Content of fumed silica in the film

[0090] Example 2-1

[0091] A porous film was manufactured in the same manner as in Example 1-1, except that the amounts of EVA and fumed silica were changed to 5 parts by weight and 7.5 parts by weight, respectively.

[0092] Example 2-2

[0093] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 18.8 parts by weight and 6 parts by weight, respectively.

[0094] Example 2-3

[0095] A porous film was manufactured using the same method as in Example 1-3 above.

[0096] Example 2-4

[0097] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 21.8 parts by weight and 3 parts by weight, respectively.

[0098] Example 2-5

[0099] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 23.3 parts by weight and 1.5 parts by weight, respectively.

[0100] Example 2-6

[0101] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 24.5 parts by weight and 0.3 parts by weight, respectively.

[0102] Example 2-7

[0103] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 24.71 parts by weight and 0.09 parts by weight, respectively.

[0104] Example 2-8

[0105] A porous film was manufactured in the same manner as in Example 1-8, except that the amounts of EVA and fumed silica were changed to 5 parts by weight and 9 parts by weight, respectively.

[0106] Example 2-9

[0107] A porous film was manufactured in the same manner as in Example 1-9, except that the amounts of EVA and fumed silica were changed to 5 parts by weight and 9 parts by weight, respectively.

[0108] Example 2-10

[0109] A porous film was manufactured in the same manner as in Example 1-10, except that the amounts of EVA and fumed silica were changed to 5 parts by weight and 9 parts by weight, respectively.

[0110] Comparative Example 2-1

[0111] A porous film was manufactured in the same manner as in Example 2-1, except that fumed silica was not used and the amount of PE1 added was changed to 24.8 parts by weight.

[0112] Comparative Example 2-2

[0113] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 15.8 parts by weight and 9 parts by weight, respectively.

[0114] Comparative Example 2-3

[0115] A porous film was manufactured in the same manner as in Example 2-1, except that the amounts of PE1 and fumed silica were changed to 14.9 parts by weight and 9.9 parts by weight, respectively.

[0116] 3. Content of ethylene vinyl acetate and fumed silica in the film

[0117] Example 3-1

[0118] 11.8 parts by weight of polyethylene (UHMWPE, PE2) having a weight average molecular weight (Mw) of 2,000,000, 9 parts by weight of ethylene vinyl acetate (EVA) having a vinyl acetate content of 28 wt%, 9 parts by weight of fumed silica, 0.2 parts by weight of antioxidant, and 70 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt at 40°C were mixed and fed into a twin-screw extruder (inner diameter 58 mm, L / D=56). Under the conditions of a screw rotation speed of 40 rpm and 200°C, the mixture was extruded from the twin-screw extruder through a T-Die having a width of 300 mm and then passed through a casting roll having a temperature of 40°C to produce a base sheet having a thickness of 800 μm.

[0119] The above base sheet was immersed in a dichloromethane leaching tank at 25°C to extract and remove paraffin oil for 1 minute, and then dried at 50°C for 5 minutes. The base sheet was stretched 8 times in the longitudinal direction (MD) in a roll stretching machine at 110°C and 8 times in the transverse direction (TD) in a tenter stretching machine at 125°C to produce a porous film.

[0120] Example 3-2

[0121] 10.8 parts by weight of polyethylene (HDPE, PE1) having a weight average molecular weight (Mw) of 600,000, 7 parts by weight of polyethylene (UHMWPE, PE2) having a weight average molecular weight (Mw) of 2,000,000, 6 parts by weight of ethylene vinyl acetate (EVA) having a vinyl acetate content of 28 wt%, 6 parts by weight of fumed silica, 0.2 parts by weight of antioxidant, and 70 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt at 40°C were mixed and fed into a twin-screw extruder (inner diameter 58 mm, L / D=56). Under the conditions of a screw rotation speed of 40 rpm and 200°C, the base sheet having a thickness of 800 μm was manufactured by extruding the material through a T-Die having a width of 300 mm from the twin-screw extruder and then passing it through a casting roll having a temperature of 40°C.

[0122] The above base sheet was immersed in a dichloromethane leaching tank at 25°C to extract and remove paraffin oil for 1 minute, and then dried at 50°C for 5 minutes. The base sheet was stretched 8 times in the longitudinal direction (MD) in a roll stretching machine at 110°C and 8 times in the transverse direction (TD) in a tenter stretching machine at 125°C to produce a porous film.

[0123] Example 3-3

[0124] A porous film was manufactured using the same method as in Example 1-3 above.

[0125] Comparative Example 3-1

[0126] A porous film was manufactured in the same manner as in Example 3-1, except that the amounts of PE2 and EVA were changed to 8.8 parts by weight and 12 parts by weight, respectively.

[0127] Comparative Example 3-2

[0128] A porous film was manufactured in the same manner as in Example 3-1, except that the amounts of PE2, EVA, and fumed silica were changed to 5.8 parts by weight, 12 parts by weight, and 12 parts by weight, respectively.

[0129] 4. Process change

[0130] Example 4

[0131] 19.8 parts by weight of polyethylene (HDPE, PE1) having a weight average molecular weight (Mw) of 600,000, 5 parts by weight of ethylene vinyl acetate (EVA) having a vinyl acetate content of 28 wt%, 5 parts by weight of fumed silica, 0.2 parts by weight of antioxidant, and 70 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt at 40°C were mixed and fed into a twin-screw extruder (inner diameter 58 mm, L / D=56). Under the conditions of a screw rotation speed of 40 rpm and 200°C, the mixture was extruded from the twin-screw extruder through a T-Die having a width of 300 mm and then passed through a casting roll having a temperature of 40°C to produce a base sheet having a thickness of 800 μm.

[0132] The above base sheet was stretched 8 times in the longitudinal direction (MD) in a roll stretching machine at 110°C, stretched 2 times in the transverse direction (TD) in a tenter stretching machine at 125°C, and then immersed in a dichloromethane leaching tank at 25°C to extract and remove paraffin oil for 1 minute. After drying at 50°C for 5 minutes, the base sheet was stretched 4 times in the transverse direction (TD) in a tenter stretching machine at 134°C to produce a porous film.

[0133] Comparative Example 4

[0134] A porous film comprising 70 wt% of polyethylene having a weight average molecular weight (Mw) of 3,150,000 and 30 wt% of polyethylene having a weight average molecular weight (Mw) of 500,000 and having a porosity of 64.9 vol% was laminated to a polyester fabric using an impermeable polyurethane adhesive applied in a discrete dot pattern using a gravure coating roll so that the polyurethane adhesive covered about 35% of the film surface, and then the polyurethane adhesive was cured. This two-layer laminate film was coated with a hydrophilic polyurethane prepolymer mixture containing a thermosetting agent at a temperature of 17 g / m 2 A moisture-permeable, waterproof film was manufactured by gravure coating and passing it through an infrared oven for about 20 seconds to crosslink the polyurethane.

[0135] Experimental example

[0136] The thickness, porosity, pore size, hydrophilicity, moisture permeability, waterproofness, tensile strength, and puncture strength of the porous films manufactured in the above examples and comparative examples were measured using the following methods. Unless otherwise specified regarding temperature, measurements were made at room temperature (25°C), and the results are shown in Tables 1 to 5 below.

[0137] - Thickness (㎛): The thickness of the porous film specimen was measured using a micro thickness measuring device.

[0138] -Porosity (volume %): The porosity of a porous film specimen with a radius of 25 mm was measured using a Capillary Porometer from PMI according to ASTM F316-03.

[0139] -Pore size (nm): Using Image-pro plus from MediaCybernetics, the pores and the real part in the porous film specimen were identified based on brightness, and the parts that could not be identified or noise were corrected with a freehand tool. The edge part that forms the outline of the pore or the pore structure observed inside the pore was identified as the pore, and the pores and the real part were binarized. After binarization, the continuous part was regarded as one pore, and the pore size (pore diameter) was calculated by assuming the area value of one pore as the surface value of the true circle. The porous film specimen was divided into areas of 2 μm x 2 μm, and the average pore size was calculated as the average value of the pore sizes measured for 10 areas.

[0140] -Hydrophilicity (%): The hydrophilicity of the porous film specimen was measured by the following method. The size of the droplet generated immediately after adding 2 μL of purified water to the surface of the porous film (MD 3.28 mm / TD 1.86 mm) and the size of the spread droplet after 5 minutes were measured along the longitudinal direction (MD) and the transverse direction (TD), and the rate of change in the size (length) of the droplet in each direction was calculated.

[0141] -Moisture permeability (MVTR, g / m) 2 / 24hr): MVTR of porous film specimens was measured according to DIN EN ISO 15496.

[0142] -Water resistance: Porous film specimens were clamped and sealed between rubber gaskets of a fixture. Water was sprayed at a pressure of 0.07 bar (1 psig) for 3 minutes on an area with a diameter of approximately 10.8 cm (4.25 inches) on one side of the specimen. Water resistance was evaluated based on whether water was observed on the other side of the specimen (O: No water observed, X: Water observed).

[0143] -Tensile strength (kgf / cm) 2): The stress applied until fracture occurred in the machine direction (MD) and transverse direction (TD) of a porous film specimen measuring 20 mm x 200 mm in size was measured using a tensile strength tester.

[0144] - Puncture strength (gf): Using a puncture strength tester, a force was applied with a stick to a porous film specimen measuring 100 mm x 50 mm until the sample was punctured, and the force applied was measured.

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single entity may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0152] The scope of the present invention is indicated by the claims set forth below, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. A hydrophobic region containing polyolefin; and A porous film having a hydrophilic region including a hydrophilic polymer and a hydrophilic inorganic material dispersed among the hydrophobic regions; The content of the hydrophilic polymer in the above porous film is 0.1 to 30 wt%, Moisture-permeable waterproof film.

2. In paragraph 1, The content of the hydrophilic inorganic material in the above porous film is 0.1 to 30 wt%, Moisture-permeable waterproof film.

3. In paragraph 1, The content of the hydrophilic region in the above porous film is 0.1 to 60 wt%, Moisture-permeable waterproof film.

4. In paragraph 3, The weight average molecular weight of the above polyolefin is 200,000 to 800,000, The content of the hydrophilic polymer in the above porous film is 0.1 to 25 wt%, The content of the hydrophilic inorganic material in the above porous film is 0.1 to 25 wt%, The content of the hydrophilic region in the above porous film is 0.2 to 45 wt%, Moisture-permeable waterproof film.

5. In paragraph 3, The weight average molecular weight of the above polyolefin is 900,000 to 2,000,000, The content of the hydrophilic polymer in the above porous film is 25 to 30 wt%, The content of the hydrophilic inorganic material in the above porous film is 25 to 30 wt%, The content of the hydrophilic region in the above porous film is 45 to 60 wt%, Moisture-permeable waterproof film.

6. In paragraph 1, The above polyolefin comprises one selected from the group consisting of polyethylene, polypropylene, polybutylene, polymethylpentene, and combinations of two or more thereof. Moisture-permeable waterproof film.

7. In paragraph 1, The hydrophilic polymer comprises one selected from the group consisting of ethylene vinyl acetate, ethylene vinyl alcohol, polyvinyl alcohol, polyacrylic acid, polyoxyethylene-polyoxypropylene block copolymer, polyethylene glycol, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl acetal, polyvinyl butyral, cellulose derivatives, polyurethane, polyamide, polyester, glycerol, and combinations of two or more thereof. Moisture-permeable waterproof film.

8. In paragraph 1, The hydrophilic inorganic material comprises one selected from the group consisting of SiO2, AlO(OH), Mg(OH)2, Al(OH)3, TiO2, BaTiO3, Li2O, LiF, LiOH, Li3N, BaO, Na2O, Li2CO3, CaCO3, LiAlO2, Al2O3, SiO, SnO, SnO2, PbO2, ZnO, P2O5, CuO, MoO, V2O5, B2O3, Si3N4, CeO2, Mn3O4, Sn2P2O7, Sn2B2O5, Sn2BPO6, talc, and a combination of two or more thereof. Moisture-permeable waterproof film.

9. In paragraph 1, The porosity of the above porous film is 60 to 90 volume%, Moisture-permeable waterproof film.

10. In paragraph 1, The average pore size of the above porous film is 100 to 200 nm. Moisture-permeable waterproof film.

11. In paragraph 1, The change rate in the longitudinal direction (MD) length from immediately after the droplet is dropped on the surface of the porous film to the point where 5 minutes have passed is 20 to 50%, and the change rate in the transverse direction (TD) length is 20 to 50%. Moisture-permeable waterproof film.

12. In paragraph 1, The water vapor transmission rate (MVTR) of the above porous film measured according to EN ISO 15496 is 5,000 to 20,000 g / m 2 / 24hr, Moisture-permeable waterproof film.

13. In paragraph 1, The above porous film satisfies at least one of the conditions (i) to (iv) below. Waterproof and breathable film: (i) Thickness 1 to 30㎛, (ii) Perforation strength of 500gf or more, (iii) Longitudinal (MD) tensile strength 1,000 to 3,000 kgf / cm 2 , (iv) Transverse direction (TD) tensile strength 1,000 to 3,000 kgf / cm 2 .

14. A moisture-permeable and waterproof film according to any one of paragraphs 1 to 13; and At least one layer combined with the above moisture-permeable waterproof film; Laminated items.

15. In paragraph 14, The above layer comprises one selected from the group consisting of a textile layer, a polymer film layer, a natural leather layer, a synthetic leather layer, a fleece layer, and a combination of two or more thereof. Laminated items.

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