JP2005088971A - Packaging bag for use in microwave oven - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging bag for use in a microwave oven, which holds a content food containing a plenty of oil or sugar, and prevents the oil of the content from penetrating a sealant layer to avoid overheating of the sealant under microwave heat even if the bag is heated in a high-power microwave, so that a packaging material is hardly damaged and the bag keeps the content packaged without bursting as the inner pressure of the bag is automatically reduced via a part where an easy steam-venting means is formed. <P>SOLUTION: A composite film, which has at least one face that is made of a sealant layer, is used to form the packaging bag. The packaging bag is composed of a lower member having an upper sealant surface, and an upper member, which has a wing portion, which is formed by making two sealant surfaces face each other and sealing together the side and the top side of the two surfaces, and an under sealant surface. The upper and lower members are made to overlap each other, and the periphery of the overlapping members is sealed together to form the packaging bag. The steam-venting means is formed in the wing portion. The sealant layer is made of a polyolefin resin composition containing an antiblocking agent of 0.01-3.0 wt%. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention does not peel off due to pressure or impact applied during transportation or storage, and does not rupture while heating the contents in a microwave oven, and can automatically reduce the internal pressure. The present invention relates to a microwaveable packaging bag.

  More specifically, as a content, in addition to solid food, for example, liquid foods such as curry and soup, various foods and drinks such as drinking water are hermetically packaged, and the contents remain with the bag placed horizontally. The present invention relates to a microwave packaging bag that can be heated safely without spilling.

  In recent years, with the widespread development of microwave ovens, and in response to the demand for simplified cooking, cooked processed foods are packaged in plastic packaging bags, etc., sealed and distributed in a form that preserves them. ing.

  However, when such foods are heated in a microwave oven, if the packaging bag remains sealed, the internal pressure in the bag rises due to water vapor generated from the contents by heating, and eventually the contents burst, It was often scattered in the range.

  As a packaging container that prevents such a rupture of the packaging bag, for example, a microwave packaging bag is proposed in which a portion of the packaging bag is scissored and a vent is formed before heating in the microwave oven. (For example, refer to Patent Document 1).

Further, a weakly sealing thin film tape is interposed in a part of the heat seal portion of the bag, and the easy peel surface of the bottom member is peeled off and a vent hole is opened when the inside of the packaging bag becomes a predetermined pressure or more. A microwave packaging bag has been proposed (see, for example, Patent Document 2).
JP 2000-72187 A However, since the packaging bag of Patent Document 1 needs to cut a part of the packaging bag with scissors in advance and form a vent before heating with the microwave oven, it takes time and effort. In addition, there is a disadvantage that it is cumbersome and the consumer forgets the work of forming the vent before heating, and the bag may be ruptured by heating, which is very dangerous.

  Moreover, since the packaging bag of patent document 2 is sealed so that it may be easily peeled off from the easy peel surface, there is a drawback that the content leaks from the seal surface due to pressure or impact applied in the distribution process.

Prior to the present application, the present applicant, as a packaging container that has improved the disadvantages of such packaging bags, a lower member with the heat seal surface as the upper surface, the heat seal surfaces facing each other, Is a packaging bag in which a wing part is formed, an upper member having a heat seal surface as a lower surface is overlapped, and a peripheral seal part is heat sealed to form a main seal part, which is controlled in the region of the wing part. A microwave packaging bag is proposed in which a seal portion and a point seal portion are provided, and at least one easy-to-heat means is applied to the point seal portion (see, for example, Patent Document 3).
JP, 2003-155070, A However, in the packaging bag of patent documents 3, when using food and drinks with a lot of oil and sugar as contents, and using a microwave oven for business with high output, etc., it is heated with a microwave oven. When the inside of the packaging bag is equal to or higher than a predetermined pressure, there is a drawback in that a hole is also formed in a portion where the easy steaming means is not applied.

  The object of the present invention is to use food and drinks rich in oil and sugar as contents, and even when using a microwave oven for business use with a high output, etc. An object of the present invention is to provide a packaging bag for a microwave oven that can automatically reduce the internal pressure from a portion that has been subjected to easy-permeability means without causing rupture while the contents are packaged.

  Accordingly, in order to solve the above-mentioned problems, the invention according to claim 1 is a bag for heating with a microwave oven, wherein the sealant surface is an upper surface using a composite film having at least one surface made of a sealant layer. The lower member and the sealant surfaces facing each other to form a wing that seals the side and the tip side, and the upper member with the sealant surface as the bottom surface are overlapped, and the peripheral edge is sealed to Sealing as a seal part, forming a point seal part in the central region in the wing part, and providing at least one easy-to-vaporize means in the point seal part, wherein the sealant layer What discovered the packaging bag for microwave ovens which consists of a polyolefin-type resin composition which contains 0.01 weight%-3.0 weight% of blocking agents A.

  The invention according to claim 2 is a polyolefin system in which the sealant layer has a multilayer structure, and the innermost layer of the sealant layer contains 0.01 wt% to 3.0 wt% of an antiblocking agent. It is the packaging bag for microwave ovens which consists of a resin composition and the other layer becomes a structure which consists of polyolefin resin.

  Moreover, invention of Claim 3 is a packaging bag for microwave ovens in which the unsealed part is formed inside the said point seal part.

  Moreover, invention of Claim 4 is a packaging bag for microwave ovens in which the pattern seal part is formed inside the said point seal part.

  Moreover, the invention of Claim 5 is a packaging bag for microwave ovens which uses the said evaporating means as a cutting blade or a notch.

  Further, in the invention according to claim 6, when the point seal portion draws a circle centering on the center portion of the bag, the radius of the circle contacting the bottom end of the point seal portion from the center of the bag is the side seal. It is the packaging bag for microwave ovens provided in the position shorter than the radius of the circle which touches a part inner edge.

  Moreover, the invention of Claim 7 is a packaging bag for microwave ovens which makes the distance of the lowest end of the evaporating means provided in the said point seal part, and the point seal part lower end part 2 mm-10 mm.

  The invention according to claim 8 is the microwave oven packaging bag in which the control seal portion is provided substantially parallel to the upper end side of the wing portion from the left and right side seals of the wing portion toward the point seal portion.

  The invention according to claim 9 is a microwave oven packaging bag in which the control seal portion is provided symmetrically.

  The invention according to claim 10 is characterized in that the tip position of the control seal part is a circle that is in contact with the lower end of the evaporating means when a concentric circle is drawn from the center of the bag, and a circle that is in contact with the upper end of the point seal part. And the ratio of the distance from the end of the pouch to the end of the point seal part and the distance from the tip of the left and right control seal parts is 8/7 or more.

  The invention according to claim 11 is a microwave oven packaging bag in which the ratio of the length from the end portion of the packaging bag to the wing portion and the length from the wing portion to the other end portion is 2/3 or less.

  The invention according to claim 12 is a microwave oven packaging bag in which the seal strength after retorting is 5 N / 15 mm or more and 25 N / 15 mm or less under a temperature condition of 90 ° C. or more.

  In the microwave packaging bag of the present invention, the contents of the food and drink with a lot of oil and sugar are contained in the sealant layer by heating the microwave oven even when using a microwave oven for business use with high output. Because the oil content of the product does not penetrate and the oil portion penetrated into the sealant is not heated excessively, the packaging material is not easily damaged, and when heated in a microwave oven and the inside of the packaging bag exceeds the predetermined pressure In addition, there is an advantage that the internal pressure can be automatically reduced from the portion subjected to the easy-permeability means without causing rupture while the contents are packaged.

  1A and 1B are diagrams showing an embodiment of a packaging bag 1 for a microwave oven according to the present invention, wherein FIG. 1A is a perspective view, FIG. 1B is a diagram of the configuration of the packaging bag, FIG. Sectional view of laminate 10 of packaging material forming packaging bag, (e) Sectional view of laminate 10 of another aspect of packaging material forming packaging bag, (f) Still another aspect of packaging material forming packaging bag It is sectional drawing of the laminated body 10 of.

  FIG. 2 is an explanatory diagram when forming a packaging bag, (a) an explanatory diagram when the packaging bag is formed from two pieces of material, and (b) an explanatory diagram when the packaging bag is formed from one piece of material. It is.

FIG. 3 is an explanatory diagram of the formation position of the point seal portion 9 in the microwave packaging bag,
FIG. 4 is a view showing the seal shape of the point seal portion 9, FIG. 5 is a view showing the shape of the easily steaming means in the point seal portion, and FIG. 6 is an example of the shape of the seal portion in the wing portion. FIG.

  FIG. 7 is a view showing an embodiment of a packaging bag for a microwave oven according to the present invention, wherein (a) a perspective view, (b) an explanatory view of the length of a control seal portion, (c) a point seal portion 9 and a control seal portion. It is explanatory drawing of formation positions, such as 5c.

  FIG. 8 is an explanatory diagram of the shape of the control seal portion 5c provided in the wing portion 4 in the microwave packaging bag 1 of the present invention.

  As shown in FIGS. 1A to 1C, a microwave packaging bag 1 according to the present invention uses a composite film composed of a heat-resistant substrate layer 12 and a sealant layer 15, and has a sealant surface. The lower member 2 having the upper surface as a top surface and the wing portion 4 in which the sealant surfaces face each other and the side portions and the tip side portions thereof are sealed are formed, and the upper member 3 with the sealant surface as the lower surface is overlapped. And is sealed as a main seal portion, and a point seal portion 9 is formed in the central region in the wing portion 4, and the point seal portion 9 is constituted by a packaging bag provided with at least one easy-to-vaporize means. The sealant layer 15 is made of a polyolefin-based resin composition containing 0.01 wt% to 3.0 wt% of the antiblocking agent, so that the oil component or the like derived from the contents penetrates the sealant layer. Therefore, it does not rupture even when the food and beverage containing a lot of oil and sugar are wrapped in a microwave oven and the inside of the packaging bag exceeds the specified pressure. It is a packaging bag that can reduce the temperature, and can be used for a microwave oven with high output.

  Next, the laminated body 10 which forms the packaging bag 1 for microwave ovens of this invention is shown in FIG.1 (d). As shown in FIG.1 (d), the heat resistant base material layer 12, the printed layer 13, the contact bonding layer 14, and antiblocking. And a sealant layer 15a made of a polyolefin-based resin composition containing 0.01 wt% to 3.0 wt% of an agent.

  Note that the print layer 13 and the adhesive layer 14 are not essential layers but are provided as necessary.

  Moreover, as shown in FIG.1 (e), you may provide the intermediate | middle layer 16 between the layers of the heat resistant base material layer 12 and the sealant layer 15 as needed.

  In addition, as shown in FIG. 1 (f), in the multilayer sealant layer, when the packaging bag is produced, the innermost sealant layer 15b that comes into contact with the contents contains 0.01 wt.% Of the antiblocking agent. A layer (base material layer side) 15a laminated on the innermost sealant layer is composed of a polyolefin resin layer.

  In FIG. 1F, although not shown, an intermediate layer may be provided between the heat-resistant base material layer 12 and the sealant layer 15 as necessary.

  The sealant layer 15 constituting each member of the packaging bag in the present invention is an innermost layer that comes into contact with the contents when the packaging bag is produced as an essential layer, and an antiblocking agent is added in an amount of 0.01% by weight to A polyolefin resin composition containing 3.0% by weight.

  Examples of the polyolefin resin that is the main component of the sealant layer 15 according to the present invention include a low density polyethylene resin film, a linear low density polyethylene resin film, a medium density polyethylene resin film, a high density polyethylene resin film, and an unstretched polypropylene. Polyolefin resins such as resin films, ethylene-propylene copolymer films, linear ethylene-α-olefin copolymer films, polybutene resins, or polymethylpentene resins alone or two or more blended resin films Among the films, any one or more kinds of films are used and can be a single-layer sealant layer or a multilayer sealant layer.

The density of the resin, in the range of 0.90g / cm ³ ~0.96g / cm ³ is, by using the sealant layer by adding an antiblocking agent to be described later to the resin, the heating in a microwave oven In doing so, it is preferable because the oil content can hardly effectively penetrate into the bag.

  The sealant layer may be formed by extrusion lamination of these resins, or may be formed as a film formed in advance by the T-die method or the inflation method.

  The thickness of these sealant layers 16 is usually preferably 20 μm to 100 μm, more preferably 30 μm to 60 μm.

  In particular, among the above linear ethylene-α-olefin copolymers, ethylene-copolymerized α-olefins having 3 to 10 carbon atoms with 0.2 mol% to 20 mol% are transported during freezing. It is preferable because it is excellent in sealing strength and impact resistance during storage and storage, and more preferably 1 mol% to 10 mol% copolymerized.

  Examples of the α-olefin include butene-1, pentene-1, hexene-1, heptene-1, octene-1, nonene-1, decene-1, 4-methylpentene-1, and the like. preferable.

The density of the linear ethylene -α- olefin copolymer is preferably ^{0.90g / cm 3 ~0.96g / cm 3} , at 0.91g / cm ³ ~0.945g / cm ³ More preferably.

  By using an anti-blocking agent, which will be described later, to the linear ethylene-α-olefin copolymer and using a sealant layer, sealing strength during freezing, transportation, storage, etc., impact resistance, transparency This is preferable because it can effectively express the function that the oil content of the contents hardly penetrates into the bag when heated in a microwave oven.

On the other hand, if it is less than 0.90 g / cm ³ , even if an anti-blocking agent is added, the function that the oil content of the contents hardly penetrates into the bag cannot be effectively expressed. If the density exceeds 0.96 g / cm ³ , the seal strength, impact resistance, and transparency during freezing, transportation, storage, etc. are inferior.

  The melt flow rate of the linear ethylene-α-olefin copolymer is preferably 0.1 g / 10 min to 10 g / 10 min, and preferably 0.5 g / 10 min to 5 g / 10 min. preferable.

  This is preferable because it is excellent in sealing strength and impact resistance during freezing, transportation, storage and the like.

  On the other hand, if the melt flow rate is less than 0.1 g / 10 min, the moldability is inferior, and if it exceeds 10 g / 10 min, the impact strength decreases, which is not preferable.

  Moreover, as the multilayer sealant layer according to the present invention, the innermost layer 15b of the sealant layer is composed of a polyolefin-based resin composition containing 0.01% by weight to 3.0% by weight of the above antiblocking agent. The layer-side sealant layer 15a is made of a polyolefin resin.

  Specifically, as the sealant layer 15a on the base material layer side, a polyolefin resin selected from an ethylene polymer, an ethylene copolymer, a propylene polymer, and a propylene copolymer may be used alone or in combination. Can be used. Two or more other layers may be stacked.

  Among them, it is preferable to use the same resin as that used for the sealant layer 15b on the innermost layer side because of excellent interlayer adhesion.

  There is no restriction | limiting in particular as an antiblocking agent added to the sealant layer 15 concerning this invention, For example, a silica type, a silicone type, a zeolite type, a talc etc. can be used.

  In addition, you may use said antiblocking agent individually or in combination of 2 or more types, respectively.

  The addition amount of the anti-blocking agent is preferably in the range of 0.01% by weight to 3% by weight and preferably in the range of 0.1% by weight to 3% by weight in the polyolefin resin composition. More preferred.

  By this, when heated in a microwave oven, the oil content of the contents does not penetrate into the sealant layer, and the oil content part that has penetrated the sealant is not excessively heated, so the packaging material is not easily damaged, When the inside of the packaging bag is equal to or higher than a predetermined pressure, there is an advantage that the internal pressure can be automatically reduced from the portion where the easy-permeability means is applied without rupturing while the contents are packaged.

  When the addition amount of the anti-blocking agent is less than 0.01% by weight, the oil content of the contents penetrates into the sealant layer due to heating in the microwave, so extra heat is applied to the portion where the oil content penetrates, and the packaging material It is not preferable because it may burst due to damage.

  Moreover, when the addition amount of an antiblocking agent exceeds 3 weight%, since transparency of a resin and shaping | molding stability fall, it is unpreferable.

  The heat-resistant substrate layer 12 is not particularly limited as long as it is generally used as a packaging material for frozen foods or chilled foods that are heated or cooked in a microwave oven. When the is manufactured, it is provided so as to be arranged outside.

  For example, stretched polyethylene terephthalate film, silica-deposited polyethylene terephthalate film, alumina-deposited polyethylene terephthalate film, stretched nylon film, silica-deposited stretched nylon film, alumina-deposited stretched nylon film, stretched polypropylene film, polyvinyl alcohol-coated stretched polypropylene film, nylon 6 / meta Any film among xylenediamine nylon 6 co-pressed co-stretched film, polypropylene / ethylene-vinyl alcohol copolymer co-pressed co-stretched film and the like can be used.

  These heat resistant resin layers 12 usually have a melting point of 150 ° C. or higher, and a thickness of 10 μm to 50 μm can be used.

  The printing layer 13 is provided for the purpose of displaying contents or imparting aesthetics by a conventionally known printing method or the like, and is not an essential layer but is provided as necessary.

  Usually, the printed layer 13 may be formed so as to be on the upper surface side or the lower surface side of the heat-resistant base material layer 12 when the packaging bag is produced.

  In addition, as the intermediate | middle layer 16, you may provide between the heat resistant base material layers 12 and the sealant layer 15 as needed.

  As the intermediate layer 16, for example, one or both of an oxygen barrier layer and a shock absorbing resin layer can be provided. Further, several layers of these layers can be provided.

  For example, as the oxygen barrier layer, a vinylidene chloride film, an ethylene-vinyl alcohol copolymer film, or an inorganic vapor deposition film can be used.

  As the shock absorbing resin layer, a nylon film is preferably used.

  The nylon film can be suitably used regardless of whether it is uniaxially stretched, biaxially stretched or unstretched.

  The thickness of the shock absorbing resin layer is not particularly limited, but is usually in the range of 5 μm to 40 μm, preferably 10 μm to 30 μm.

  Known additives such as lubricants, antioxidants, antistatic agents, antifogging agents, and coloring agents are added to the resin forming each layer of the packaging material as needed, as long as the object of the present invention is not impaired. be able to.

  The addition amount can be arbitrarily added from a very small amount to several tens of percent depending on the purpose.

  Next, in the present invention described above, a method for producing a laminate using the above materials will be described. As such a method, the heat-resistant substrate layer 12, (if necessary, the intermediate layer 16), The interlayer of the sealant layer 15 is, for example, a dry lamination method in which lamination is performed using a laminating adhesive, or an extrusion lamination method in which lamination is performed through a melt-extruded resin layer using a melt-extrusion adhesive resin. An adhesive layer 14 can be formed.

  In the above, as the laminating adhesive, for example, one-part or two-part curable or non-cured vinyl type, (meth) acrylic type, polyamide type, polyester type, polyether type, polyurethane type, epoxy type, etc. It is possible to use adhesives for laminating such as rubber type, other solvent type, aqueous type, or emulsion type.

  As a coating method of the adhesive for laminating, for example, direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, fountain method, transfer roll coating method, and other methods can be used. .

As the coating ^{amount, 0.1g / m 2 ~10g / m} 2 ( dry state) position are ^{preferred, 1g / m 2 ~5g / m} 2 ( dry state) position is more preferred.

  In the above, as the melt extrudable resin layer, a resin layer made of a thermoplastic resin layer is used and can be used for bonding the respective layers.

  Specifically, the material of the adhesive melt extrudable resin layer includes a low density polyethylene resin, a medium density polyethylene resin, a high density polyethylene resin, a linear low density polyethylene resin, and ethylene polymerized using a metallocene catalyst.・ Copolymer resin with α-olefin, ethylene / polypropylene copolymer resin, ethylene / vinyl acetate copolymer resin, ethylene / acrylic acid copolymer resin, ethylene / ethyl acrylate copolymer resin, ethylene / methacrylic resin Acid copolymer resin, ethylene / methyl methacrylate copolymer resin, ethylene / maleic acid copolymer resin, ionomer resin, polyolefin resin, unsaturated carboxylic acid, unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, ester A resin obtained by graft polymerization or copolymerization of a monomer, and maleic anhydride as a polyolefin. It can be used a graft modified resin or the like resin.

  These materials can be used alone or in combination.

  The thickness of the resin layer is preferably about 10 μm to 30 μm.

  In addition, when performing said lamination | stacking, if necessary, it can pre-process, such as a corona treatment, an ozone treatment, a frame process, etc., and can laminate | stack.

  The above-mentioned surface pretreatment is carried out as a method for improving the adhesion and the like when laminating each resin film or sheet and each layer. As a method for improving the above adhesion, for example, A primer coat agent layer, an undercoat agent layer, an anchor coat agent layer, and the like can be arbitrarily formed in advance on the surface of various resin films or sheets to form a surface treatment layer.

  Examples of the pretreatment coating agent layer include polyester resins, polyamide resins, polyurethane resins, epoxy resins, phenol resins, (meth) acrylic resins, polyvinyl acetate resins, polyethylene, and polypropylene. A resin composition containing a polyolefin resin or a copolymer or modified resin thereof, a cellulose resin, or the like as a main component of the vehicle can be used.

  The microwave oven laminate 10 described above forms a lower member with the sealant surface as an upper surface, and a wing portion where the sealant surfaces face each other and the side portion and the tip side portion are sealed, with the sealant surface as the lower surface. The packaging bag for a microwave oven in the form according to the present invention can be manufactured by overlaying the upper member, sealing the peripheral edge portion and sealing it as a main seal portion.

  Further, as a method of heat sealing, for example, known methods such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, an ultrasonic seal, etc. Can be done by the method.

  Next, the seal strength of the packaging bag according to the present invention will be described. The seal strength is 30 N / 15 mm to 100 N / 15 mm at room temperature of 23 ° C., due to handling, transportation, storage, etc. at room temperature or when frozen. Is preferable because the seal part does not peel off and opens.

  Further, the seal strength is preferably in the range of 5 N / 15 mm to 20 N / 15 mm, and more preferably in the range of 10 N / 15 mm to 15 N / 15 mm in a high temperature range of 90 ° C. or higher.

  As a result, when the packaging bag filled with the contents is heated in a microwave oven, the heat and pressure of the steam generated by the heating is surely and promptly peeled and retracted at the portion provided with the means for easy vaporization in the wing portion. Then, it is preferable because it is easy to dissipate steam from the cut portion or the like and easily open it.

  On the other hand, if the seal strength is less than 30 N / 15 mm at room temperature of 25 ° C., the seal portion may be peeled off and opened depending on handling, transportation, storage, etc. at room temperature or during freezing, which is not preferable.

  In addition, when the seal strength exceeds 25 N / 15 mm in a high temperature range of 90 ° C. or higher, when heated in a microwave oven, the point seal portion does not quickly peel and retreat, and steam cannot escape. It is not preferable.

  In addition, you may make a difference in the seal strength of a wing part and a main seal part, and you may make only the seal strength of a wing part weaker than another seal part.

  The method of forming the microwave packaging bag 1 according to the present invention in which the wing portion 4 is provided is not limited to the above-described three-piece method, but, as shown in FIG. A method of folding in may also be used. In this case, the tip of the wing portion 4 may not be sealed and may be the folded portion f1. However, in the case of providing easy-evaporation means, a seal portion may be partially provided.

  Moreover, as shown in FIG.2 (b), the bag making method which made all the upper members and the lower member 1 piece K may be sufficient. In this case, the tip of the wing portion 4 may not be sealed, and the folded portion f1 may be used. However, even in this case, when the easy-to-vapor means is provided, the seal portion may be partially provided. . Furthermore, it is good also as the folding | returning part f2, without giving a seal also to one edge part of a packaging bag.

  As shown in FIG. 3, the packaging bag 1 according to the present invention is provided with a wing portion 4 in the packaging bag, and is connected to the wing portion upper end side seal portion or the folded portion at the tip in the central region of the wing 4. Easily steaming means such as a cut 7 is provided in the point seal portion 9 and the point seal portion 9.

  The position where the point seal portion 9 is formed is such that when a circle centered on the center portion of the bag is drawn, the radius r2 of the circle that is in contact with the lowermost end of the point seal portion 9 from the center of the bag is in contact with the inner edge of the side seal portion. It is formed at a position that is shorter than the radius r1.

  As a result, the steam generated by heating can be dissipated out of the bag without rupturing the bag from the seal peeling and reversing means of the point seal portion 9 and the easy steaming means, so the bag is opened in advance with a bag or the like. Without having the bag placed horizontally on the tray of the microwave oven, it can be heated.

  On the other hand, when the radius r2 is longer than the radius r1, the peeling and retreating of the seal part due to the heat of steam generated by heating and the increase of internal pressure results in the peeling at the side seal part 5d of the main seal part of the packaging bag. It is not preferable because the packaging bag may break or the contents may leak.

  The position where the point seal portion 9 is formed is preferably a seal connected to the seal portion at the upper end side portion of the wing portion 4.

  As a result, when heated in a microwave oven, the pressure concentrates on the point seal portion 9, and the seal peels off from the edge of the point seal portion 9 and passes through a notch or the like, which is an easy-to-condense means. It has the advantage that more generated steam is quickly discharged out of the bag. Further, when the point seal portion 9 is formed, since the upper side seal and the point seal portion of the wing portion 4 can be integrally sealed, there is an advantage that the productivity is good.

  On the other hand, when the point seal portion 9 is an independent seal, the pressure of the steam generated by heating the microwave oven passes between the upper seal of the wing portion and the independent point seal portion. It is difficult to apply pressure to the point seal portion efficiently, and automatic opening does not occur smoothly. Also, when filling the contents or between the independent point seal portion 9 and the wing portion 4 in the course of distribution. This is not preferable because the contents enter and a poor appearance occurs. Furthermore, since the independent point seal part and the upper seal of the wing part are sealed in two steps, the productivity of the sealing process is inferior.

  As for the position of the wing part 4 provided in the packaging bag for microwave ovens of this invention, it is preferable that a / b is 2/3 or less, as shown to Fig.1 (a).

  If a / b is larger than 2/3, the internal force generated by heating of the microwave oven is not applied to the point seal portion 9 provided in the wing portion 4, the seal peeling and retreat does not proceed quickly, and automatic opening is not achieved. It is not preferable.

  In the present invention, as shown in FIG. 4, the shape of the point seal portion formed in the central region of the wing portion is not limited to a square, rectangle, circle, ellipse, triangle, or the like.

  The point seal portion may be a solid seal as shown in FIGS. 4 (a) and 4 (b), or an unsealed portion 6N may be provided inside as shown in FIG. 4 (c). As shown in FIG.4 (d), it is good also as a pattern seal | sticker part 6P inside.

  The shape of the pattern seal portion 6P is not particularly defined, and examples thereof include a mesh shape, a stripe shape, a lattice shape, and a polka dot shape.

  Among them, by providing the unsealed portion 6N inside, even if the position for forming the easy-vaporizing means such as the notch 7 and the notch 8 formed in the unsealed portion 6N is shifted compared to the case of the solid seal, The distance at which the seal peels and retreats is constant, and when peeling reaches the inside of the unsealed portion 6N, it can be opened at once by the easy-to-vaporize means applied to the unsealed portion 6N. In addition, there is an advantage that it is possible to perform stable and quick steam venting.

  Next, as shown in FIG. 5, the notch 7 or the notch, which is an easily steaming means formed inside the point seal portion 9, causes the point seal portion to peel and recede due to the heat of steam generated by heating and the increase in internal pressure. Any shape that allows vapor to dissipate out of the bag is acceptable.

  The number of the cuts 7 or notches is not limited to one, and may be plural.

  In addition, since this easy-to-steam means is inside surrounded by the point seal portion 9, it can be kept completely sealed in the distribution stage and is hygienic.

  Further, as shown in FIG. 6, in the case of a solid seal type point seal portion and in the case of a point seal portion provided with a pattern seal portion 6P therein, the lower end of the easy-to-vapour means (the figure shows an example of incision) In the case of a point seal part provided with an unsealed part 6N in the distance w1 between the part and the lower end part of the point seal part, the seal width w2 below the point seal part may be in the range of 2 mm to 10 mm. Preferably, it is in the range of 3 mm to 5 mm.

  On the other hand, if the distance w1 or the width w2 is smaller than 2 mm, the strength against vibration, dropping, etc. is weakened, and there is a possibility that the bag breaks during distribution of the product, which is not preferable.

  Further, when the distance w1 or the width w2 is larger than 10 mm, it is not preferable because the steam escape hardly occurs and the bag breakage from other seal portions may occur.

  As shown in FIG. 7 (a), the packaging bag according to the present invention is controlled to be substantially parallel to the upper end side of the wing portion from the left and right side seals of the wing portion toward the point seal portion together with the point seal portion. It is preferable to provide the seal portion 5c.

  Thus, the heat and pressure of the steam generated by heating the microwave oven can be adjusted so as to be appropriately applied to the point seal portion.

  Further, it is preferable that the control seal portion 5c is substantially symmetrical.

  If the control seal part is asymmetrical on the left and right sides, it is not preferable since the automatic opening cannot be achieved well because the pressure applied to the point seal part 9 is biased. The conventional seal as an easy-vapor means is a weak seal compared to the peripheral seal of the packaging bag, but both the point seal portion 9 and the control seal 5c provided in the wing portion 4 in the present invention are the same as the peripheral seal of the packaging bag. Since it consists of the same seal, there is stability of strength in distribution.

  Next, the positional relationship for forming the control seal portion 5c and the point seal portion will be described. The tip of the control seal portion 5c is easy when a concentric circle is written from the center of the pouch, as shown in FIG. The side seal portion of the main seal portion is included between the point seal portion 9 and the contact point between the wing portion upper end side 5a from the lower end of the notch or notch, which is a steaming means, and as shown in FIG. The ratio d1 / d2 between the distance d1 between 5d and the lower end of the point seal portion 9 and the distance d2 between the side seal portion 5d of the main seal portion and the tips of the left and right control seal portions 5c is preferably 8/7 or more.

  On the other hand, if the control seal part 5c is short, the pressure is suddenly concentrated on the point seal part during heating, and the contents are cut and spilled from the notch or a loud noise is generated. It is not preferable because it gives a feeling of fear.

  On the other hand, if the control seal portion 5c is too long, the pressure is not sufficiently concentrated on the point seal portion, and the bag may be broken from other seal portions, which is not preferable.

  The control seal portion 5c can have various shapes within a range that satisfies the above conditions.

  For example, the control seal portion 5c may be a solid seal, or as shown in FIGS. 8A to 8D, the upper portion of the control seal portion 5c is formed by a combination of straight and curved seal lines. The inside of the independent sealing portion R may be unsealed or may be a pattern seal. Further, in the solid seal or the independent sealing portion R, the same shape as the easy-permeability means provided in the point seal portion or the above-mentioned various easy-permeability means may be provided.

  As shown to Fig.8 (a), you may provide the notch 7 in the right-and-left independent sealing part R. As shown in FIG.

  Easy steaming provided in the point seal section 9 when steam is suddenly generated in contents with high moisture content or heating in a microwave oven with high output by providing easy steaming means on the solid seal or the independent sealing section. It has the effect of stabilizing the steam escape as well as the dissipation of steam from the means.

  In the present invention, the microwave packaging bag produced as described above is, for example, solid food such as frozen sushi, curry, soup, soy sauce, sauce, soup stock, spices, cooking liquor, fruit juice, water, etc. It can be filled and packaged with various fluid foods and foods and drinks, especially when food and drinks with high oil content and sugar content are filled and packaged as a content, it is heated in a microwave oven and the inside of the packaging bag exceeds the predetermined pressure. Then, the internal pressure can be automatically reduced from the portion where the easy-to-vaporize means is applied without rupturing while the contents are packaged.

  The present invention will be further described below with reference to examples and comparative examples.

  After forming a linear low density polyethylene resin film having a thickness of 60 μm with an inflation molding machine, a resin composition obtained by adding 1.0% by weight of a silica-based antiblocking agent (particle size 5 μm) to a linear low density polyethylene resin Corona discharge treatment was performed on one side so that the surface tension was about 48 dyne / cm 2.

  Next, this linear low-density polyethylene resin film was dry-laminated with a biaxially stretched nylon resin film having a thickness of 15 μm via a urethane adhesive to obtain a packaging material for a microwave oven according to the present invention.

  A packaging bag for a microwave oven having a wing part according to the present invention as shown in FIG. 7A was produced using the packaging material (c: 130 mm, d: 120 mm, e: 50 mm, f: 28 mm, (D1: 58mm of FIG.7 (c), d2: 38mm).

120 g of meat sauce as a content is put into the packaging bag obtained above, sealed and sealed, and heated for 45 seconds in a 1100 W microwave oven. As a result, the content does not spill and breaks from the main seal part. Without any problem, the steam gently escaped from the notch after 15 seconds.
[Comparative Example 1]
Except for not adding a silica-based antiblocking agent to the linear low density polyethylene resin, using the same packaging material as in Example 1, in the form shown in FIG. Produced.

  Although the meat sauce 120g was put into the packaging bag obtained above as a content, sealed and sealed, and heated for 45 seconds in a microwave oven of 1100W, the steam gently escaped from the cut portion after 15 seconds. A small hole opened in the corner of the lower surface of the packaging bag, and the packaging material was damaged.

It is a figure which shows the Example of the packaging bag for microwave ovens of this invention, (a) Perspective view, (b) The figure of a structure of a packaging bag, (c) X1-X1 part sectional drawing, (d) Form a packaging bag. Cross-sectional view of laminate of packaging material, (e) Cross-sectional view of laminate of another embodiment of packaging material forming packaging bag, (f) Cross-sectional view of laminate of yet another embodiment of packaging material forming packaging bag is there. It is explanatory drawing in the case of forming a packaging bag, (a) It is explanatory drawing in the case of forming a packaging bag from 2 pieces of materials, (b) It is explanatory drawing in the case of forming a packaging bag from 1 piece of materials. It is explanatory drawing of the formation position of the point seal | sticker part in the packaging bag for microwave ovens. It is a figure which shows the seal shape of a point seal part. It is a figure which shows the shape of the easily steaming means in a point seal part. It is a figure explaining the Example of the seal part shape in a wing part. It is a figure which shows the Example of the packaging bag for microwave ovens of this invention, (a) Perspective view, (b) Explanatory drawing of the length of a control seal part, (c) The formation position of a point seal part, a control seal part, etc. It is explanatory drawing. It is explanatory drawing of the shape of the control seal part provided in the wing part in the packaging bag for microwave ovens of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Packaging bag 2 for microwave ovens of this invention Lower member 3 Upper member 4 Wing part 5a Seal part 5b of upper end side part of wing part Side seal part 5c of wing part Control seal part 5d Side seal part 6 of main seal part Seal part 6N Unsealed part 6P Pattern seal part 7 Notch 8 Notch 9 Point seal part 10 Laminated body 12 Heat resistant base material layer 13 Print layer 14 Adhesive layer 15 Sealant layer 15a Sealant layer (base material layer side)
15b Sealant layer (innermost layer side)
16 Intermediate layer f1, f2 Folded part r1, r2 Radius R Independent sealing part K 1 piece member

Claims (12)

  A bag for heating by a microwave oven, using a composite film composed of at least one sealant layer, a lower member with the sealant surface as the upper surface, and the side and tip sides facing each other The wing part is sealed, and the upper member with the sealant surface as the lower surface is overlapped, and the peripheral part is sealed and sealed as the main seal part, and the point seal part is formed in the central region in the wing part. A polyolefin-based resin, which is a packaging bag in which at least one evaporating means is provided in the point seal portion, and the sealant layer contains 0.01 wt% to 3.0 wt% of an antiblocking agent. A packaging bag for a microwave oven comprising the composition.   A bag for heating by a microwave oven, using a composite film composed of a sealant layer at least on one side, a lower member with the sealant surface as an upper surface, and a side portion and a tip side portion with the sealant surfaces facing each other The wing part is sealed, and the upper member with the sealant surface as the lower surface is overlapped, and the peripheral part is sealed and sealed as the main seal part, and the point seal part is formed in the central region in the wing part. , A packaging bag in which at least one easy-permeability means is provided in the point seal portion, the sealant layer has a multi-layer structure, and the innermost layer of the sealant layer contains an anti-blocking agent. Characterized in that it comprises a polyolefin resin composition containing 0.01 wt% to 3.0 wt%, and the other layer comprises a polyolefin resin. Microwave packaging bag for that.   The unsealed part is formed inside the said point seal part, The packaging bag for microwave ovens in any one of Claims 1-2 characterized by the above-mentioned.   The packaging bag for microwave ovens according to any one of claims 1 to 2, wherein a pattern seal part is formed inside the point seal part.   The microwaveable packaging bag according to any one of claims 1 to 4, wherein the easily steaming means is a cutting blade or a notch.   When the point seal part draws a circle centered on the center part of the bag, the radius of the circle in contact with the bottom end of the point seal part from the center of the bag is shorter than the radius of the circle in contact with the inner edge of the side seal part. It is provided in such a position, The microwave oven packaging bag according to any one of claims 1 to 5.   The microwave oven packaging according to any one of claims 1 to 6, wherein a distance between the lowermost end of the easy-evaporating means provided in the point seal portion and the lower end portion of the point seal portion is 2 mm to 10 mm. bag.   The microwave oven according to any one of claims 1 to 7, wherein a control seal portion is provided substantially parallel to the upper end side of the wing portion from the left and right side seals of the wing portion toward the point seal portion. Packaging bag.   The packaging bag for a microwave oven according to any one of claims 1 to 8, wherein the control seal part is provided symmetrically.   The tip position of the control seal portion is included between a circle that contacts the lower end of the easy-permeability means when drawing a concentric circle from the center of the bag and a circle that contacts the upper end of the point seal portion, and the end of the pouch The microwave packaging bag according to any one of claims 1 to 9, wherein a ratio of a distance from the tip to the end of the point seal part and a distance from the tip of the left and right control seal parts is 8/7 or more. .   The ratio of the length from the said packaging bag edge part to a wing part and a wing part to the other end part is 2/3 or less, The packaging for microwave ovens in any one of Claims 1-10 characterized by the above-mentioned. bag. 12. The microwave oven packaging bag according to claim 1, wherein the seal strength after retorting is 5 N / 15 mm or more and 25 N / 15 mm or less under a temperature condition of 90 ° C. or more.

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