JP2015189127A - Multilayer film for fusion cutting in bag making, packaging bag, and manufacturing method of multilayer film for fusion cutting in bag making - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer film for fusion cutting in bag making, which can be used for a bag for packaging foods such as fruits and vegetables, excellent in antifogging, allowing the moisture vapor transpired from the packaged food itself not to be condensed on the internal surface of the film due to discharge of the extra moisture to the outside, stably achieving high fusion seal strength even when fusion cut at a high speed, with excellent fusion sealability; a packaging bag; and a manufacturing method of a multilayer film for fusion cutting in bag making.SOLUTION: A multilayer film for fusion cutting in bag making includes a first film layer having a fusion seal strength of 1.5 kg/15 mm or more with at least moisture vapor permeability, and a second film layer having antifogging properties. The first film layer has a moisture vapor permeability of 40 g/mday (40°C, 90% RH) or more and 180 g/mday (40°C, 90% RH) or less. The first film layer and the second film layer have an adhesion of 0.25 kgf/15 mm or more. A packaging bag and a manufacturing method of a multilayer film for fusion cutting in bag making are also provided.

Description

  The present invention relates to a multilayer film for fusing and bag making. More specifically, the present invention provides a multilayer film for fusing bags, a packaging bag, and an excellent antifogging effect without water droplets adhering to the inner surface of the packaging bag, even when used for a packaging bag of food such as fruits and vegetables. The present invention relates to a method for producing a multilayer film for fusing bags.

  Conventionally, biaxially stretched polystyrene films that have been used in packaging bags for foods such as fruits and vegetables can easily be creased or torn, and biaxially stretched polypropylene films are often used. These films are inexpensive, have excellent transparency, rigidity, surface hardness, impact resistance, moisture resistance, and the like, and have an excellent function as a packaging bag material film for foods such as fruits and vegetables. In addition, because of its high crystallinity, it has a relatively high melting point and thus has excellent heat resistance.

  By the way, the above biaxially stretched polystyrene film and biaxially stretched polypropylene film have low permeability to water vapor and the surface thereof is extremely hydrophobic. In many cases, condensation occurs on the inner surface of the film by water vapor evaporated from the film to form an aggregate of minute water droplets, and so-called cloudiness is often generated. In particular, since foods such as fruits and vegetables contain a lot of moisture, such fogging is likely to occur, and it becomes difficult to distinguish the contents in the packaging bag. This is not only a serious drawback for the transparency of packaging bags, which is important for confirming the contents, but also water that is unevenly agglomerated and adhered to foods such as fruits and vegetables stored in the packaging bags. Such as deteriorating quality and contributing to corruption. For this reason, many films suitable for packaging bags for foods such as fruits and vegetables that do not cause the above fogging have been developed.

For example, as these films, a film in which the surface of a biaxially stretched polystyrene film or the like is coated with a mixture of polyglycerin fatty acid ester (A) and diglycerin fatty acid ester (B) (Patent Document 1), viscosity measured at 25 ° C. A film made of a resin composition that can obtain an antifogging film containing 0.1 to 20% by weight of a surfactant having a viscosity of 100 to 1500 mPa · s (Patent Document 2) Or a monolayer or multilayer polymer film having a water vapor transmission rate of 20 g / m ² · 24 Hr · at 40 ° C. · 90% RH or more, wherein the polymer film is a polyester resin film, a polyamide resin film, polyvinyl Alcohol resin film, ethylene-vinyl alcohol copolymer resin film, ethylene-vinegar A single-layer or multilayer polymer film containing at least one of acid-vinyl copolymer resin films (Patent Document 3), an intermediate layer formed of a propylene homopolymer, and front and back surfaces sandwiching the intermediate layer Provided with a skin layer formed of a propylene random copolymer, and the intermediate layer contains 0.005 to 0.1 parts by weight of a crystallization nucleating agent with respect to 100 parts by weight of the propylene homopolymer. An OPP film for fusing sealing (Patent Document 4) is disclosed. However, even in a packaging bag using such an improved film, it is easy to break into the film and the appearance deteriorates, and it is easy to tear. When packaged, dew condensation occurs on the inner surface of the bag, and fogging may occur due to dew condensation. If stored for a long time, fruits and vegetables are damaged.

  By the way, packaging bags for foods such as fruits and vegetables are manufactured by fusing and sealing the film. Since the biaxially stretched polystyrene film and the biaxially stretched polypropylene film have a relatively high melting point, it is necessary to increase the fusing seal temperature. In recent years, the speed of the fusing seal has been gradually increased in order to increase productivity, but the fusing seal temperature cannot be maintained at a high temperature due to the increase in speed, and the fusing seal strength is reduced, or the fusing seal strength is reduced. There is a problem that there is variation. In Patent Document 4, by adding a crystallization nucleating agent to the intermediate layer, the crystallization speed is adjusted in the process in which the molten resin forming the sealing ball after the fusing seal is cooled and solidified, and the edge of the sealing ball after the fusing seal is obtained. A method for improving the fusing sealability under high-speed conditions by eliminating the breakage of the film from the part and eliminating the brittleness against the stress of the seal ball has been proposed. Since it is an OPP film having low permeability to water, it is still not sufficient.

JP 2003-105112 A JP 2001-247777 A JP 2001-146291 A JP 2013-027977 A JP 2001-059028 A

  Even if the present invention is used for a packaging bag for food such as fruits and vegetables, it is difficult for folds to enter, it is difficult to tear, and it does not cause condensation on the inner surface of the film due to water vapor evaporated from the food packaging itself such as fruits and vegetables. Multilayer film for fusing bags and packaging bags with excellent antifogging properties because water vapor can be released to the outside, and stable fusing seal strength even when fusing at high speeds, so that fusing seal strength is also excellent. And it aims at providing the manufacturing method of the multilayer film for fusing bag making.

The present inventors have intensively studied to solve the above problems. As a result, it is a multilayer film for fusing and bag making having a fusing seal strength of 1.5 kg / 15 mm or more, comprising at least a first film layer having water vapor permeability and a second film layer having antifogging properties. The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less, In the adhesion test carried out by the following procedures (1) to (5), the second film layer is a multi-layer film for fusing bag making having an adhesion of 0.25 kgf / 15 mm or more in food packaging bags such as fruits and vegetables. Even if it is used, excess water vapor can be released to the outside without condensation on the inner surface of the film due to water vapor evaporated from the food packaging itself such as fruits and vegetables. Even if fusing Since the constant to heat-sealing strength is obtained, it found to be excellent in fusing sealability. As a result of further studies based on these findings, the present invention has been completed.
(procedure)
(1) A multilayer film having a width of 15 mm and a length of 80 mm having a first film layer and a second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm, and is pressure-bonded with a rubber roller. Prepare 10 or more test pieces on which the crimping part is formed,
(3) Masking the multilayer film and the tape other than the crimping part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the distance between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are stretched to 140 mm. Attached to the testing machine,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, measure the maximum load (kgf / 15 mm) between them, and average Takes a value.

That is, the present invention includes the following aspects.
[1] A multilayer film for fusing bag making, having a fusing seal strength of 1.5 kg / 15 mm or more, having at least a water vapor permeability, a second film layer having antifogging properties, The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less, 1 film layer and said 2nd film layer have the adhesiveness of 0.25 kgf / 15mm or more in the adhesiveness test performed in the following procedures (1)-(5), The multilayer film for fusing bag making characterized by the above-mentioned .
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value.
[2] Further, an anchor coat layer is provided between the first film layer and the second film layer, and the anchor coat layer has a solid content coating amount of 1 mg / m ² or more and 40 mg / m ² or less. The multilayer film for fusing and bag making according to [1], comprising:
[3] The fusing bag according to [1] or [2], wherein the first film layer contains a polyamide-based resin, and the second film layer contains an ethylene / vinyl alcohol copolymer resin. Multilayer film.
[4] The multilayer film for fusing bags according to [3], wherein the polyamide-based resin is biaxially stretched nylon.
[5] The multilayer film for fusing and bag making according to any one of [1] to [4], wherein the second film layer contains a nonionic surfactant as an antifogging agent.
[6] The multilayer film for fusing bags according to [5], wherein the nonionic surfactant contains a polyglycerol fatty acid ester.
[7] The [1] to [6], wherein the nonionic surfactant has a content of 1.0% by mass or more and 5.0% by mass or less per solid content of the second film layer. ] The multilayer film for fusing bag making described in any one of the above.
[8] The multilayer film for fusing and bag making according to any one of [1] to [7], wherein the second film layer has a thickness of 0.1 μm or more and 20.0 μm or less.
[9] The multilayer film for fusing bags according to any one of [1] to [8], which has a haze of 2% to 10%.
[10] A packaging bag comprising the multilayer film for fusing and bag making according to any one of [1] to [9], wherein the second film layer is an innermost layer.
[11] A method for manufacturing a multilayer film for fusing bag making, wherein the multilayer film for fusing bag making has a fusing seal strength of 1.5 kg / 15 mm or more and a first film layer having water vapor permeability is prepared. A step of applying and drying an anchor coat agent on at least one surface of the first film layer to form an anchor coat layer, and a surface of the anchor coat layer on which the first film layer is provided. And a step of applying and drying a base material of a second film layer having antifogging properties on the opposite surface to form the second film layer, wherein the first film layer is 40 g / m ^2. -It has a water vapor permeability of not less than day (40 ° C, 90% RH) and not more than 180 g / m ² · day (40 ° C, 90% RH), and the first film layer and the second film layer have the following procedures. Adhesion performed in (1) to (5) In the test, a method for manufacturing a multilayer film for fusing bag characterized by having a higher adhesiveness 0.25 kgf / 15 mm.
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value.
[12] A method for manufacturing a multilayer film for fusing bag making, wherein the multilayer film for fusing bag making has a fusing seal strength of 1.5 kg / 15 mm or more and a first film layer having water vapor permeability is prepared. A step of applying and drying an anchor coat agent on at least one surface of the first film layer to form an anchor coat layer, and a surface of the anchor coat layer on which the first film layer is provided. A second film layer having antifogging properties separately prepared and bonded to the surface opposite to the surface, and forming the second film layer,
The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less, and the first film layer And the second film layer has an adhesion of 0.25 kgf / 15 mm or more in an adhesion test performed by the following procedures (1) to (5). .
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value.

  The multilayer film for fusing bags and the packaging bag of the present invention is good for appearance because it is difficult to break into the film even if it is used for food packaging bags such as fruits and vegetables. Excess water vapor can be released to the outside without condensation on the inner surface of the film due to vaporized water vapor, so it is excellent in anti-fogging property, and even if it is melted at high speed, fusing seal strength is obtained stably, so fusing Excellent sealing performance. Moreover, the manufacturing method of the multilayer film for fusing bag making of this invention can manufacture the multilayer film for fusing bag making easily.

It is sectional drawing which shows the multilayer film for fusing bag making concerning 1st Embodiment of this invention. It is explanatory drawing of the adhesive test with respect to the multilayer film for fusing bag making of this invention. It is explanatory drawing of the compatibility test with respect to the multilayer film for fusing bag making of this invention.

The multilayer film for fusing bag making of the present invention comprises a first film layer having a fusing seal strength of 1.5 kg / 15 mm or more, having at least water vapor permeability, and a second film layer having antifogging properties. The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less, The second film layer has an adhesion of 0.25 kgf / 15 mm or more in an adhesion test performed in the following procedures (1) to (5).
(1) Prepare a multilayer film for fusing and bag making having a width of 15 mm and a length of 80 mm having a first film layer and a second film layer,
(2) Prepare a tape with a width of 15 mm and a length of 80 mm, and attach the tape to the second film layer side of the multilayer film so that the bonded portion is 15 mm wide and 10 mm long, and press with a rubber roller Prepare 10 or more test pieces on which the crimping part is formed,
(3) Mask the areas other than the multilayer film and the pressure bonding part of the tape,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the distance between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are stretched to 140 mm. Attached to the testing machine,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, measure the maximum load (kgf / 15 mm) between them, and average Takes a value.

  The multilayer film for fusing bag making according to the first embodiment of the present invention is shown in FIG. As shown in FIG. 1, the multilayer film 10 for fusing and bag making according to the present invention includes at least a first film layer 1 having water vapor permeability and a second film layer 2 having antifogging properties. If necessary, an anchor coat layer 3 may be further provided between the first film layer 1 and the second film layer 2.

  Hereinafter, 1. First film layer, 2. Second film layer, 3. Anchor coat layer, 4. 4. Adhesion test, Compatibility test, 6. 6. Multilayer film for fusing bag making, The packaging bag will be described in detail.

1. 1st film layer The 1st film layer 1 consists of a transparent resin film layer, and is a base material layer for maintaining the intensity | strength of the multilayer film 10 for fusing bag making. The 1st film layer 1 has the function to discharge | release the water vapor | steam transpired from foodstuffs, such as fruits and vegetables, outside. Moreover, it has the function which is excellent in fusing sealing property.

In the present invention, the first film layer 1 has a water vapor permeability of 40 g / m ² · day or more and 180 g / m ² · day or less as measured according to JIS Z 0208 (40 ° C., 90% RH). And 50 g / m ² · day to 150 g / m ² · day, preferably 50 g / m ² · day to 130 g / m ² · day. If it is lower than 40 g / m ² · day, condensation may occur on the inner surface of the packaging bag due to water vapor evaporating from the food itself such as fruits and vegetables. If it is higher than 180 g / m ² · day, It may become susceptible to the environment, and moisture from the fruits and vegetables itself may evaporate, resulting in drying of the fruits and vegetables and other foods. .

  In the present invention, the first film layer 1 preferably contains a polyamide resin. 50 mass% or more and 100 mass% or less are preferable, as for content of the polyamide-type resin per solid content of the 1st film layer 1, 70 mass% or more and 100 mass% or less are more preferable, and it is still more preferable that it is 100 mass%. As the polyamide-based resin, nylon is preferable, and biaxially stretched nylon is more preferable. Nylon 6, Nylon 11, Nylon 12, Nylon 66, Nylon 6 · 10, Nylon 6 · 12, Nylon 6 · T, Nylon 6 · I, Nylon 9. T, nylon M5T, polymetaxylylene adipamide (MXD nylon), etc. alone or in combination of two or more are preferred, nylon 6, nylon 11, nylon 12, and nylon 66 alone or in combination of two or more are more preferred, Nylon 6 and nylon 66 alone or in combination of two are more preferred.

  The 1st film layer 1 can contain resin other than a polyamide-type resin as needed. The resin other than the polyamide resin is not particularly limited. For example, polypropylene, low density polyethylene, linear low density polyethylene, medium / high density polyethylene, ethylene / vinyl acetate copolymer, polystyrene, polyvinylidene chloride, polyvinyl alcohol, ethylene / vinyl alcohol copolymer, polyvinyl chloride, polyvinyl chloride Examples include vinylidene, cellophane, polyacrylonitrile, polyester (polyethylene terephthalate, polylactic acid, copolymerized polyester, etc.), polycarbonate, and the like, and combinations thereof. Of these resins, resins having high compatibility with the polyamide-based resin are preferable.

  The 1st film layer 1 can contain an inorganic type filler as needed. The inorganic filler is not particularly limited. Examples thereof include minerals (inorganic crystals) such as zeolite, sepiolite, diatomaceous earth, silica gel, arobene, imogolite, montmorillonite, attapulgite, or zonotolite.

  The first film layer 1 may be a heat stabilizer, a lubricant, an antifogging agent, an impact resistance improving agent, a processing aid, an antistatic agent, an ultraviolet absorber, an antioxidant, a wrinkle resistance preventing agent, or a filling, as necessary. Additives such as agents, pigments, and the like can be contained within a range that does not impair the performance of the resin film.

  The first film layer 1 is manufactured by mixing and melting a polyamide-based resin and other resins, inorganic fillers, additives, and the like, if necessary, by a T-die method (uniaxial stretching, biaxial stretching, unstretched) or an inflation method. Since the stiffness of the film can be increased, it is preferable to manufacture by a T-die method (uniaxial stretching or biaxial stretching) or an inflation method. The thickness of the obtained first film layer 1 is preferably 15 μm or more and 40 μm or less, and more preferably 20 μm or more and 30 μm or less. If it is thinner than 15 μm, it may be poor in appearance when packaged, or the strength may be insufficient. If it is thicker than 40 μm, flexibility may be inferior.

2. 2nd film layer The 2nd film layer 2 has a function as an innermost antifogging layer of the packaging bag manufactured with the multilayer film 10 for fusing bag making. The second film layer 2 contains a resin that is a base material and a surfactant that is an antifogging agent. The antifogging agent is preferably a nonionic surfactant.

  The resin used as the base material is preferably a resin excellent in affinity and compatibility with the nonionic surfactant so that the second film layer 2 is a transparent film without white turbidity. Moreover, when manufacturing a packaging bag from the multilayer film 10 for fusing bag making by high speed fusing, resin with high compatibility with the 1st film layer 1 is preferable in order to obtain sufficient fusing seal strength stably.

  The content of the resin used for the second film layer 2 is preferably 60% by mass or more and 98.5% by mass or less, and more preferably 70% by mass or more and 98.5% by mass or less based on the solid content of the second film layer 2. 80 mass% or more and 98.5 mass% or less is still more preferable. When the resin content is less than 60% by mass, the compatibility with the first film layer 1 is lowered, and the adhesion between the first film layer 1 and the second film layer 2 may be deteriorated.

  The resin used for the second film layer 2 is preferably a vinyl alcohol resin. Examples of vinyl alcohol resins include saponification products of fatty acid vinyl ester polymers (single or copolymer) such as polyvinyl alcohol (fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol), partially acetalized polyvinyl alcohol, ethylene Examples include vinyl alcohol copolymer resins, vinyl alcohol-ethylene sulfonic acid copolymer resins, vinyl alcohol-maleic acid copolymer resins, and the like. These vinyl alcohol resins can be used alone or in combination of two or more. Among these, ethylene / vinyl alcohol copolymer resin is more preferable.

  The ethylene / vinyl alcohol copolymer resin can be mixed uniformly and transparently without clouding even when mixed with a nonionic surfactant as an antifogging agent, and can be firmly adhered to the nylon of the first film layer 1. It has excellent performance such as high fusing and sealing properties when manufacturing packaging bags. Unless particularly required, the resin used for the second film layer 2 is preferably an ethylene / vinyl alcohol copolymer resin alone.

  Resin used for the 2nd film layer 2 can contain resin other than ethylene-vinyl alcohol copolymer resin as needed. An example of such a resin is a thermoplastic resin. Examples include the vinyl alcohol resins, acrylic resins, ester resins, olefin resins, vinyl chloride resins, polyamide resins, and combinations thereof. Among these, ethylene vinyl such as the vinyl alcohol resins A resin having high compatibility with the alcohol copolymer resin is preferable.

  The nonionic surfactant that is an antifogging agent has a function of improving the antifogging property of the multilayer film 10 for fusing and making bags, and is uniformly mixed with the resin. The nonionic surfactant preferably has a content of 1.0% by mass or more and 5.0% by mass or less per solid content of the second film layer, and is 2.0% by mass or more and 4.0% by mass or less. The content is more preferably 1.5% by mass or more and 3.5% by mass or less.

  In the present invention, as the nonionic surfactant, glycerin fatty acid ester, polyglycerin fatty acid ester, polyethylene glycol fatty acid ester, polyethylene glycol sorbitan fatty acid ester, polyoxyethylene alkyl ether, sorbitan fatty acid ester, alkyldiethanolamine, alkyldiethanolamide, etc. These are preferably used alone or in combination, and polyglycerol fatty acid esters are more preferred.

  In the polyglycerol fatty acid ester, 70% by weight or more of the constituent fatty acid is a saturated and / or unsaturated fatty acid having 12 to 18 carbon atoms, preferably 12 to 16 carbon atoms, preferably a saturated fatty acid. Further, it is preferable that the degree of polycondensation (the degree of polycondensation of the largest component when the degree of polycondensation is distributed) is 4 to 20 and the monoester is 50 mol% or more. Specific examples of the constituent fatty acid include lauric acid, myristic acid, palmitic acid, stearic acid, aragydic acid, oleic acid, elaidic acid, ricinoleic acid, 2-butyloctanoic acid, 2-hydroquindecanoic acid and the like. More specifically, it is preferable to contain lauric acid, myristic acid, palmitic acid alone or two or more of 70% by weight or more of the total constituent fatty acids, and the remainder is 10 carbon atoms or less such as capric acid or caprylic acid and / or Alternatively, it may contain a saturated fatty acid having 18 or more carbon atoms such as stearic acid or arachidic acid, or an unsaturated fatty acid such as myristoleic acid, palmitoleic acid or oleic acid.

  Such polyglycerol fatty acid esters include diglycerol monooleate, diglycerol monolaurate, diglycerol monostearate, diglycerol monopalmitate, diglycerol monobehenate, diglycerol sesquioleate, diglycerol sesquilaurate, di Glycerin sesquistearate, diglycerin sesquipalmitate, diglycerin sesquibehenate, diglycerin dioleate, diglycerin dilaurate, diglycerin distearate, diglycerin dipalmitate, diglycerin dibehenate, triglycerin oleate, tri Glycerin laurate, tetraglycerin oleate, tetraglycerin stearate, hexaglycerin laurate, hexaglycerin oleate, degaglycerin oleate, decaglycerin Laurate, etc. may be exemplified. Of these nonionic surfactants, decaglycerin laurate is preferable because it has high antifogging properties and high compatibility with resins.

  The nonionic surfactant used for the second film layer 2 can be used in combination with the nonionic surfactant other than the polyglycerol fatty acid ester. Specific examples of these nonionic surfactants include polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene Ethylene stearyl phenyl ether, polyethylene glycol oleate, polyethylene glycol laurate, polyethylene glycol stearate, polyoxyethylene glycerol laurate, polyoxyethylene glycerol oleate, polyoxyethylene sorbitan oleate, polyoxyethylene Sorbitan laurate, polyoxyethylene sorbitan stearate, Polyoxyethylene sorbitan oleyl ether, polyoxyethylene sorbitan lauryl ether, polyoxyethylene sorbitan stearyl ether.

  The second film layer 2 is made of a mineral such as zeolite, sepiolite, diatomaceous earth, silica gel, arobene, imogolite, montmorillonite, attapulgite, or zonotrite, if necessary, such as adjusting its water vapor permeability and water contact angle. Etc. may be contained in a range that does not impair the performance of the second film layer 2.

  The second film layer 2 is made of a heat stabilizer, a lubricant, an antifogging agent other than the above, an impact resistance improving agent, a processing aid, an antistatic agent, an ultraviolet absorber, an antioxidant, and a wrinkle-resistant deterioration prevention as necessary. You may contain additives, such as an agent, an inorganic particle, a filler, and a pigment, in the range which does not impair the performance of the 2nd film layer 2.

  The second film layer 2 can be manufactured, for example, as follows. That is, the second film layer 2 is a melt obtained by melting the composition containing the resin, the surfactant, and, if necessary, other additives, or the resin (dispersoid) is dispersed in a dispersion medium. A dispersion in which the above-mentioned surfactant and other additives as necessary are mixed with the above-mentioned dispersion, or a solution in which the above-mentioned resin and the above-mentioned surfactant and, if necessary, other additives are dissolved in a solvent. The melt, dispersion or melt is applied to and dried on a substrate film having a smooth surface and a peelable surface, which is then peeled off from the substrate. The peeled second film layer 2 is adhered and laminated to the first film layer 1 by being bonded to the first film layer 1 at room temperature or thermocompression bonding. Alternatively, the second film layer 2 applied to the substrate film and dried may be laminated on the first film layer 1 while being attached to the substrate film by room temperature pressure bonding or thermocompression bonding, and then the substrate film may be peeled off. . Alternatively, a laminate can be produced by directly applying and drying the melt, dispersion or melt on the surface of the first film layer 1 without using a substrate film. Alternatively, the first film layer 1 and the second film layer 2 may be laminated by an extrusion laminating method, a coextrusion laminating method, and a dry laminating method in which a molten resin is extruded on the surface of the first film layer.

  The thickness of the second film layer 2 is preferably from 0.1 μm to 20.0 μm, more preferably from 0.2 μm to 15.0 μm, and even more preferably from 0.5 μm to 2.0 μm. When the thickness of the second film layer 2 is thinner than 0.1 μm, the strength of the packaging bag made of the fusing bag-making multilayer film 10 may be insufficient, and when it is thicker than 20.0 μm, the fruits and vegetables The permeability of water vapor evaporating from the food packaging itself may be inferior.

  The water contact angle of the surface of the second film layer 2 located on the inner surface of the packaging bag is preferably 0 ° or more and 50 ° or less, more preferably 0 ° or more and 40 ° or less, and further preferably 0 ° or more and 30 ° or less. If the water contact angle is larger than 50 °, the antifogging property may be inferior.

3. Anchor coat layer The anchor coat layer 3 can be provided between the first film layer 1 and the second film layer 2. The anchor coat layer 3 is such that the first film layer 1 and the second film layer 2 have an adhesion of 0.25 kgf / 15 mm or more in the adhesion test performed in the procedures (5) to (9) described above. , Has a function to ensure close contact. That is, when the second film layer 2 is bonded to the first film layer 1 at room temperature, when the heating temperature at the time of thermocompression bonding is low, or when the compatibility between the first film layer 1 and the second film layer 2 is not sufficient, etc. The adhesion between the first film layer 1 and the second film layer 2 may not be sufficient. Even in such a case, by providing the anchor coat layer 3, the above-described adhesion can be stably imparted.

  Anchor coat agents used for the anchor coat layer 3 are so-called dry laminate adhesives such as urethane and acrylic, titanate adhesives, imine adhesives, butadiene adhesives, polyester adhesives, olefin adhesives, An adhesive such as can be used.

Anchor coat layer 3 is preferably solid coating amount of 1.5 mg / ^{m 2} or more 40 mg / ^{m 2} or less, 5 mg / ^{m 2} or more 30 mg / ^{m 2} or less, more preferably. If the amount is less than 1.5 mg / m ² , the adhesiveness of the second film layer 2 may be insufficient. If the amount is more than 40 mg / m ² , the fusing seal strength may be lowered or the second film layer 2 may be reduced. In some cases, the water contact angle exceeds 50 ° and condensation occurs, or the water vapor permeability from the inside of the packaging bag deteriorates and condensation occurs.

When the mass of the anchor coat layer 3 is C and the mass of the second film layer 2 is B, the following three formulas can be used from the viewpoint of exhibiting and maintaining antifogging properties, ease of production, and suppressing peeling of the second film layer 2. It is preferable to satisfy all.
C ≦ 0.03 (g / m ² ) (1)
B ≧ 0.40 (g / m ² ) (2)
210 ≧ B / C ≧ 13 (3)

4). Adhesion test In the present invention, the first film layer 1 and the second film layer 2 have an adhesion of 0.25 kgf / 15 mm or more in the adhesion test performed in the procedures (1) to (5) described above. 0.28 kgf / 15 mm or more is more preferable, and 0.30 kgf / 15 mm or more is particularly preferable. When the adhesion between the first film layer 1 and the second film layer 2 is lower than 0.25 kgf / 15 mm, the second film layer 2 may be peeled off during use and sufficient antifogging properties may not be obtained. is there.

  FIG. 2 is an explanatory view of an adhesion test for the fusing bag-making multilayer film 10 of the present invention. The adhesion test in the present invention is a test method based on the “heat seal strength test” of JIS Z 0238 (1998). The difference from this test method is mainly the relative movement speed between grips. is there. The details of the experimental method are described below.

(General test conditions)
The standard condition of the test place shall be the standard temperature and humidity state class 2 [temperature 23 ± 2 ° C, relative humidity (50 ± 5)%] specified in JIS K 7100. Conditioning to balance with

(Test equipment)
The test apparatus uses a constant speed tension type tensile tester (pendulum type) or a constant speed extension type tensile tester (resistance wire strain gauge type) and meets the following conditions.
(A) The two grips shall be centered on the same plane parallel to the tensile direction, and the test piece shall be kept on one plane without slipping during the test.
(B) The load until the test piece breaks can be indicated with an accuracy of ± 2%. This correction is performed according to JIS P 8113.
(C) The breaking load is 15-85% of the capacity of the testing machine.
(D) The relative moving speed between the grips is 200 ± 20 mm / min.

(sample)
First, a multilayer film 10 for fusing and bag making having a width of 15 mm and a length of 80 mm having a first film layer 1 and a second film layer 2 is prepared.

  A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape 4 is pasted on the second film layer 2 side of the multilayer film 10 for fusing and bag making so that the bonded portion has a width of 15 mm and a length of 10 mm. Any tape 4 can be used as long as it can be confirmed that the first film layer 1 and the second film layer 2 are in close contact of 0.25 kgf / 15 mm or more. For example, the pylon OPP crystal adhesive tape # 30 Transparent (Kyowa Co., Ltd.) is used.

  Next, the bonded portion of the fusing bag making multilayer film 10 and the tape 4 is pressure-bonded with a rubber roller to form a crimping portion 11, and an adhesive tape other than the fusing bag making multilayer film 10 and the tape 4 pressure bonding portion 11. Is masked to prepare a test piece 13A.

(operation)
With the crimping part 11 of the test piece 13A at the center, the fusing bag making multilayer film and the tape are opened at 180 °, the gap between the grips is 50 mm or more, and the end of the fusing bag making multilayer film 10 in the direction perpendicular to the tape 4 Are attached to a tensile testing machine with a developed end length of 140 mm. In the direction of the arrow shown in FIG. 2, the test piece 13A is pulled at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, and a tensile load is applied until the crimping portion 11 breaks, and the maximum load (kgf / 15mm). Ten or more test pieces 13A are measured and averaged to obtain the adhesion between the first film layer 1 and the second film layer 2. At the time of measurement, the value of the test piece 13A broken at the grip portion is discarded, and the test piece 13A corresponding to this value is added for testing.

  In this adhesion test, if it is less than 0.25 kgf / 15 mm, the adhesion between the first film layer 1 and the second film layer 2 is low, and the first film layer 1 and the second film layer 2 peel off during use. As a result, sufficient antifogging properties may not be obtained.

5. Compatibility test Furthermore, in this invention, the 1st film layer 1 and the 2nd film layer 2 are 0.40 kgf / 15mm or more compatibility in the compatibility test performed in the procedure (6)-(9) shown below. Preferably 0.50 kgf / 15 mm or more, more preferably 0.70 kgf / 15 mm or more. When the compatibility between the first film layer 1 and the second film layer 2 is lower than 0.40 kgf / 15 mm, the fusing and sealing property of the fusing bag making multilayer film 10 is not sufficient and the fusing bag is likely to break. May be.

  FIG. 3 is an explanatory view of a compatibility test for the multilayer film 10 for fusing bags according to the present invention. The compatibility test in the present invention is a test method based on the “heat seal strength test” of JIS Z 0238 (1998) as in the above-described adhesion test, and the difference from this test method is mainly It is the relative movement speed between the grips.

(sample)
First, a 50 μm thick first film 1 a made of the same resin as that forming the first film layer and a 50 μm thick second film 2 a made of the same resin as that forming the second film layer are prepared. Prepare each. Next, heat sealing (sealing time 2 seconds, sealing pressure 2 kgf / cm ² ) at a temperature equal to or higher than the melting point of the resin contained in each of the first film 1a and the second film 2a, and a thermocompression bonding part having a width of 15 mm and a length of 10 mm. 12 is prepared, and a test piece 13B having a width of 15 mm, a length of 80 mm, and a developed length of 140 mm is prepared.

(operation)
The first film 1a and the second film 2a are opened at 180 ° with the thermocompression bonding part 12 of the test piece 13B as the center, the gap between the grips is set to 50 mm or more, and the perpendicular end of the first film 1a and the second film 2a A perpendicular end is attached to a tensile tester with a deployment length of 140 mm. In the direction of the arrow shown in FIG. 3, the test piece 13B is pulled at a relative moving speed between the grips of the tensile tester of 200 ± 20 mm / min, and a tensile load is applied until the thermocompression bonding part 12 breaks. kgf / 15 mm). Ten or more test pieces 13B are measured and averaged, and the first film layer 1 and the second film layer 2 are made compatible. At the time of measurement, the value of the test piece 13B broken at the grip portion is discarded, and the test piece 13B corresponding to this value is added for testing.

  In this compatibility test, if it is less than 0.40 kgf / 15 mm, the compatibility between the first film layer 1 and the second film layer 2 is low, and the first film layer 1 is formed at the fusing portion of the fusing bag making multilayer film 10. And the second film layer 2 may peel off and break the bag.

6). Multilayer film for fusing bag making The multilayer film 10 for fusing bag making of the present invention has a fusing seal strength of 1.5 kg / 15 mm or more. When the content is less than 1.5 kg / 15 mm, the possibility that the fusing part is torn when packaging contents such as fruits and vegetables is reduced, or the film piece is likely to adhere to the fusing blade. For measurement of fusing seal strength, for example, a packaging bag having an inner dimension of 130 × 180 mm is prepared so that the second film layer 2 is on the inner side under fusing seal conditions of fusing blade temperature: 430 ° C. and fusing blade angle: 90 °. Then, a test piece having a width (TD direction) of 15 mm and a length (MD direction) of 100 mm was cut out so that the melt-sealed portion was perpendicular to the sample length direction, and the atmosphere was at a temperature of 20 ° C. and a humidity of 65%. Using TENSILON RTC-1250 manufactured by Orientec Co., Ltd., both end portions in the length direction of the test piece are gripped, and measurement is performed until the melt-sealed portion breaks at a tensile speed of 200 mm / min.

Moreover, the water vapor permeability of the multilayer film 10 for fusing and bag making of the present invention has a value measured according to JIS Z 0208 (40 ° C., 90% RH) of 40 g / m ² · day to 180 g / m ² · Days or less are preferred. If it is lower than 40 g / m ² · day, condensation may occur on the inner surface of the packaging bag due to water vapor evaporating from the food itself such as fruits and vegetables. If it is higher than 180 g / m ² · day, It becomes susceptible to environmental influences, and moisture from the foods such as fruits and vegetables themselves is excessively evaporated, and the foods such as fruits and vegetables are dried, or external moisture enters, and the function as a packaging bag may deteriorate. .

  The thickness of the multilayer film 10 for fusing and bag making according to the present invention is preferably 15 μm or more and 40 μm or less. More preferably, it is 20 μm or more and 30 μm or less. When it is thinner than 15 μm, the strength may be insufficient when it is used as a packaging bag, and when it is thicker than 40 μm, the flexibility may be inferior.

  The transparency of the multilayer film 10 for fusing and bag making of the present invention preferably has a haze of 2% to 10%, more preferably 3% to 8%. If the haze is in the range of 2% or more and 10% or less, it is transparent when used as a packaging bag, and the contents stored therein can be sufficiently distinguished.

  The water contact angle (°) of one surface of the second film layer 2 of the multilayer film 10 for fusing and bag making of the present invention is preferably 0 ° or more and 50 ° or less, more preferably 0 ° or more and 40 ° or less, and 0 °. More preferably, it is 30 ° or less. The water contact angle is an index of the wettability of the surface. The smaller the value, the easier the surface gets wet, and the higher the value, the more water repellent. As a method for measuring the water contact angle of the present invention, a commercially available contact angle meter (for example, DROPMASTER-501 manufactured by Kyowa Interface Science Co., Ltd.) is used, and 2 μL of purified water is deposited on the measurement surface of the second film layer 2. Then, the water contact angle after 7 seconds is measured by an appropriate liquid method.

  The method for producing a multilayer film 10 for fusing and bag making according to the present invention includes a step of preparing a first film layer 1 having water vapor permeability, and an anchor coating agent is applied to at least one surface of the first film layer 1 at room temperature. -A step of drying to form the anchor coat layer 3, and a second film layer 2 substrate having antifogging properties on the surface of the anchor coat layer 3 opposite to the surface on which the first film layer 1 is provided. And a step of forming the second film layer 2 by coating and drying.

  Or the manufacturing method of the multilayer film 10 for fusing bag making of this invention is a process which prepares the 1st film layer 1 which has water-vapor permeability, and applies an anchor coating agent to the at least one surface of the 1st film layer 1. -A step of drying to form the anchor coat layer 3, and a second film layer 2 having antifogging properties separately prepared on the surface of the anchor coat layer 3 opposite to the surface on which the first film layer 1 is provided. Are bonded together to form a second film layer, a step of forming a die film layer by an extrusion lamination method, a step of laminating while forming the first film layer and the first film layer by coextrusion, or the first The method includes a step of pressure-bonding the film layer and the second film layer via an anchor coat (adhesion) layer.

  The multilayer film 10 for fusing and bag making according to the present invention includes a first film layer 1, a second film layer 2, and an anchor coat layer 3 as necessary, but above, below, or between these layers, Furthermore, layers having various functions can be arbitrarily added.

7). Packaging Bag The packaging bag of the present invention is produced by fusing and sealing the multilayer film 10 for fusing and bag making of the present invention so that the second film layer 2 becomes the innermost antifogging layer of the packaging bag. The packaging bag of the present invention does not cause condensation on the inner surface of the film due to water vapor evaporating from the package itself, even if food packages such as fruits and vegetables are placed in the packaging bag for a long time. The anti-fogging property is excellent, and the fusing seal strength is stably obtained even when fusing at a high speed, so that the fusing sealability is also excellent.

  The packaging bag of the present invention is not only excellent in antifogging properties and fusing sealing properties, but also in safety, hygiene, transparency, moderate rigidity, surface hardness, impact resistance, moisture resistance, oxygen barrier properties, and sealing properties. It is excellent in appearance, quality maintenance, productivity, cost, etc., and is suitable for food packaging such as fruits and vegetables.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited by the following examples. In addition,% and part described in the following Examples, Comparative Examples and Table 1 represent mass% and mass part.

  The fusing sealability, adhesion, compatibility, and water contact angle shown in the examples and comparative examples were measured by the following measuring methods.

<Fusing sealability>
Cutting blade temperature: 430 ° C
Fusing blade angle: 90 °
A packaging bag with an inner size of 130 × 180 mm was produced so that the second film layer was on the inner side under the above fusing sealing conditions. A test piece having a width (TD direction) of 15 mm and a length (MD direction) of 100 mm was cut out from the produced packaging bag so that the melt-sealed portion was perpendicular to the sample length direction. Then, in an atmosphere of a temperature of 20 ° C. and a humidity of 65%, using (TENSILON RTC-1250, Orientec Co., Ltd.), the both ends in the length direction of the test piece were grasped and fused and sealed at a tensile speed of 200 mm / min. The measurement was performed until the part broke and the fusing seal strength was measured. The fusing sealability was evaluated according to the following evaluation criteria.
[Evaluation criteria]
○: Fusing seal strength 1.5 kg / 15 mm or more ×: Fusing seal strength less than 1.5 kg / 15 mm These evaluation results are shown in Table 1.

<Measurement of adhesion between first film layer and second film layer>
Based on the test method of the above-mentioned adhesion test, a multilayer film 10 for fusing bag making having a width of 15 mm and a length of 80 mm having the first film layer 1 and the second film layer 2 is prepared. The tape 4 was affixed to the second film layer 2 side so that the bonded portion had a width of 15 mm and a length of 10 mm. Test pieces were prepared so as to have a developed length of 140 mm, and the average strength when the tape was peeled off from the film at a pulling speed of 200 mm / min was measured. The adhesion was evaluated according to the following evaluation criteria.
[Evaluation criteria]
○: Adhesiveness is less than 0.25 kgf / 15 mm and the layer does not peel ×: Adhesiveness is less than 0.25 kgf / 15 mm and the layer peels

<Measurement of compatibility between first film layer and second film layer>
Based on the experiment method of the compatibility test, the resin of the first film layer and the resin of the second film layer are thermocompression bonded at a temperature equal to or higher than the melting temperature of each resin, and the test is 15 mm wide, 80 mm long, and 140 mm long. A piece was prepared, and the average strength when the first film layer and the second film layer were peeled off at a pulling speed of 200 mm / min was measured. The compatibility was evaluated according to the following evaluation criteria.
[Evaluation criteria]
○: The thermocompression bonding part is less than 0.40 kgf / 15 mm, and the layer does not peel. ×: The thermocompression bonding part is less than 0.40 kgf / 15 mm, and the layer peels off.

<Water contact angle>
The water contact angle (°) on the second film layer side surface of the multilayer film for fusing and bag making is determined using a contact angle meter (Kyowa Interface Science Co., Ltd., DROPMASTER-501). 2 μL of purified water was dropped on the measurement surface, and the contact angle after 7 seconds from the landing was measured.

<Creation of multilayer film for fusing bags>
(Example 1)
First, on a 25 μm thick biaxially stretched nylon film (product name: Emblem ONBC-25, water vapor permeability: 108 g / m ² · day (40 ° C., 90% RH)) as a first film layer Then, a modified polybutadiene (Nippon Soda Co., Ltd., trade name: Titabond T-180E) to be an anchor coat (AC) layer is applied to 5 mg / m ^2, and a second film layer is formed thereon as a second film layer. EVOH (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) added with a clouding agent (blended diglycerin laurate and decaglycerin laurate at 95: 5) to 3.5% by weight with respect to the solid content of the second film layer , Trade name: Soarnol 16DX) was applied to 800 mg / m ² . The coating was performed by gravure coating (drying temperature 100 ° C., drying time 10 seconds). Moreover, the coating amount measured the weight (mg / m < ² >) of the coating agent at the time of coating on PET film on the same conditions, and made it a coating amount. Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

(Example 2)
A laminated film was prepared in the same manner as in Example 1 except that the coating amount of the AC layer was 3 mg / m ² . Table 1 shows the results of confirming the melt-cut sealability, adhesion, compatibility and water contact angle of this film.

(Example 3)
A laminated film was prepared in the same manner as in Example 1 except that the coating amount of the AC layer was 10 mg / m ² . Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

(Comparative Example 1)
A laminated film was prepared in the same manner as in Example 1 except that the coating amount of the AC layer was 50 mg / m ² and EVOH serving as the second film layer was coated to 80 mg / m ² . Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

(Comparative Example 2)
An ethylene / methyl acrylate copolymer (manufactured by Yashara Chemicals, trade name: Hirodine 9589) added with diglycerin laurate at 2% by weight based on the solid content of the second film layer using the second film layer as an antifogging agent was used. A laminated film was prepared in the same manner as Example 1 except for the above. Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

(Comparative Example 3)
Example 1 except that a biaxially stretched polypropylene film (trade name: P5562, manufactured by Toyobo Co., Ltd., water vapor permeability: 108 g / m ² · day (40 ° C., 90% RH)) having a thickness of 25 μm was used as the first film layer. A laminated film was prepared in the same manner as described above. Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

(Comparative Example 4)
A laminated film was prepared in the same manner as in Example 1 except that the coating amount of the AC layer was 0.9 mg / m ² . Table 1 shows the results of confirming the fusing sealability, adhesion, compatibility, and water contact angle of this film.

DESCRIPTION OF SYMBOLS 1 1st film layer 1a 1st film 2 2nd film layer 2a 2nd film 3 Anchor coat layer 4 Tape 10 Multilayer film 11 for fusing bag making Crimp part 12 Thermocompression-bonding part 13A, 13B Test piece

Claims (12)

A multilayer film for fusing bags,
It has a fusing seal strength of 1.5 kg / 15 mm or more,
A first film layer having at least water vapor permeability;
A second film layer having antifogging properties,
The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less,
The first film layer and the second film layer have an adhesiveness of 0.25 kgf / 15 mm or more in an adhesion test performed by the following procedures (1) to (5). Multilayer film.
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value. Furthermore, an anchor coat layer is provided between the first film layer and the second film layer,
The anchor coat layer, a multilayer film for fusing bag according to claim 1, characterized in that it comprises a solid coating amount of 1.5 mg / m ² or more 40 mg / m ² or less. The first film layer contains a polyamide-based resin;
The multilayer film for fusing and bag making according to claim 1 or 2, wherein the second film layer contains an ethylene / vinyl alcohol copolymer resin.   The multilayer film for fusing bags according to claim 3, wherein the polyamide-based resin is biaxially stretched nylon.   The multilayer film for fusing and bag making according to any one of claims 1 to 4, wherein the second film layer contains a nonionic surfactant as an antifogging agent.   The multilayer film for fusing bags according to claim 5, wherein the nonionic surfactant contains a polyglycerin fatty acid ester.   The nonionic surfactant has a content of 1.0% by mass or more and 5.0% by mass or less based on the solid content of the second film layer. A multilayer film for fusing bags described in 1.   The multilayer film for fusing and bag making according to any one of claims 1 to 7, wherein the second film layer has a thickness of 0.1 µm or more and 20.0 µm or less.   The multilayer film for fusing and bag making according to any one of claims 1 to 8, which has a haze of 2% or more and 10% or less.   A packaging bag comprising the multilayer film for fusing and bag making according to any one of claims 1 to 9, wherein the second film layer is an innermost layer. A method for producing a multilayer film for fusing bags,
Preparing a first film layer having water vapor permeability;
Applying and drying an anchor coat agent at room temperature on at least one surface of the first film layer to form an anchor coat layer;
Applying and drying a base material of the second film layer having antifogging property on the surface of the anchor coat layer opposite to the surface on which the first film layer is provided to form the second film layer And including
The multilayer film for fusing bag making has a fusing seal strength of 1.5 kg / 15 mm or more,
The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less,
The first film layer and the second film layer have an adhesiveness of 0.25 kgf / 15 mm or more in an adhesion test performed by the following procedures (1) to (5). A method for producing a multilayer film.
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value. A method for producing a multilayer film for fusing bags,
Preparing a first film layer having water vapor permeability;
Applying and drying an anchor coat agent at room temperature on at least one surface of the first film layer to form an anchor coat layer;
A second film layer having antifogging properties prepared separately is bonded to the surface of the anchor coat layer opposite to the surface on which the first film layer is provided by thermocompression bonding to form the second film layer. Including the steps of:
The multilayer film for fusing bag making has a fusing seal strength of 1.5 kg / 15 mm or more,
The first film layer has a water vapor permeability of 40 g / m ² · day (40 ° C., 90% RH) or more and 180 g / m ² · day (40 ° C., 90% RH) or less,
The first film layer and the second film layer have an adhesiveness of 0.25 kgf / 15 mm or more in an adhesion test performed by the following procedures (1) to (5). A method for producing a multilayer film.
(1) A multilayer film having a width of 15 mm and a length of 80 mm having the first film layer and the second film layer is prepared,
(2) A tape having a width of 15 mm and a length of 80 mm is prepared, and the tape is pasted on the second film layer side of the multilayer film so that the bonded portion has a width of 15 mm and a length of 10 mm. Prepare 10 or more test pieces that have been crimped to form a crimped part,
(3) Masking the multilayer film and the tape other than the pressure-bonding part,
(4) The multilayer film and the tape are opened at 180 ° with the crimping portion at the center, the gap between the grips is 50 mm or more, and the perpendicular end of the multilayer film and the perpendicular end of the tape are developed lengths. Attach to a tensile tester as 140mm,
(5) Pull the test piece at a relative moving speed of 200 ± 20 mm / min between the grips of the tensile tester, apply a tensile load until the crimping part breaks, and measure the maximum load (kgf / 15 mm) between them. And take the average value.

Images