JP3693991B2 - Pulp mold container - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pulp mold container having a flange portion inclined inwardly at a peripheral edge portion of a mouth portion, and a sealed container in which this is used as a container body, and a lid is bonded to the upper surface of the flange portion and sealed.
[0002]
[Prior art and problems to be solved by the invention]
A paperboard cup container containing food and drink such as instant noodles, sweets, and dairy products as food, and a container body is formed by folding and joining a paperboard having a predetermined unfolded shape. An end portion is rounded outward to form a flange portion, and a lid is thermally bonded to the flange portion and sealed.
[0003]
When the lid is thermally bonded to the flange portion as described above, it is preferable to form the flange portion flat because of the necessity of widening the bonding area. However, in the case of a paperboard container, the flange is thus formed. If the part is formed flat, the flange part is inclined inward, and the inclination angle of the flange part changes in an unstable manner due to the spring effect of the flange part, and conversely, the lid body can be thermally bonded to the flange part entirely. There was a problem that disappeared. This problem is particularly noticeable when the flange portion is hard and the upper surface portion has waviness and wrinkles.
[0004]
As a technique for suppressing the spring effect of such a flange portion, a technique described in Patent Document 1 below is known. In this technique, plastic deformation is caused on the paperboard forming the flange portion to form an annular concave groove on the lower surface side of the flange portion so that the flange portion is kept substantially horizontal.
[0005]
[Patent Document 1]
JP 54-148684 A
[0006]
On the other hand, as a cooking mode for foods and drinks, foods, etc., an accessory such as a seasoning is attached to the container main body separately from the contents stored in the container main body, and the accessory is opened after the container main body is opened There is a form to put in the main body and cook.
[0007]
When such an accessory is placed on the lid of a cup container having a flat flange portion and sealed with a lid, and further packaged with a shrink film, the top of the lid rises, and the container When displaying or packing, there is a problem that it cannot be stacked vertically. In addition, there has been a demand for a container having a function of accommodating a bulky part such as a joint part or a wrap part of the film generated on the lid even when the film is simply wrapped with a shrink film.
[0008]
Accordingly, an object of the present invention is to provide excellent lid adhesion and to accommodate the accessory when belonging to the container body in addition to the contents stored in the container body, Sealed container that can hold bulky parts such as joints and wraps of the film when wrapped with shrink film, and does not hinder vertical stacking during display or packaging A pulp mold container and a sealed container using the same may be provided.
[0009]
[Means for Solving the Problems]
In the case of a pulp mold container having a flange portion, the present inventors can obtain a desired sealing property even when the flange portion is inclined inward, and also when the container is sealed with a lid, It was found that a sealed container excellent in the above can be obtained.
[0010]
The present invention has been made on the basis of the above findings, and is a pulp mold container used for a sealing container in which a lid is curved and bonded in a concave shape and is sealed, and an inner layer container and the inner layer container With a higher density outer layer container, and at the periphery of the mouth , Has cushioning properties And turned diagonally upward It has a flange part, and the upper surface part to which the lid in the flange part is bonded is on the inside. 3-30 degrees The density of the flange portion of the inner layer container that is inclined and forms the flange portion is 0.1 to 0.6 g / cm. ^Three The above object is achieved by providing a pulp mold container.
[0011]
Further, the present invention uses the pulp mold container of the present invention as a container main body, the contents are accommodated in the container main body, a lid is bonded to the upper surface portion of the flange portion, and the mouth portion is sealed. The object is achieved by providing a sealed container having a curved portion in which the lid body is curved in a concave shape.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below based on preferred embodiments with reference to the drawings.
[0013]
FIG. 1 shows an embodiment in which the sealed container of the present invention is applied to a food container such as instant cup noodles. In FIG. 1, the code | symbol 1 has shown the sealing container.
[0014]
As shown in FIG. 1, the sealed container 1 includes a flange portion 21 having a cushioning property with a flat upper surface portion 21 a at the peripheral portion of the mouth portion 20 of the container body 2, and the contents (not shown) are included. In the accommodated state, the lid 3 is bonded to the upper surface portion 21a and the mouth portion 20 is sealed.
[0015]
As shown in FIG. 1B, the flange portion 21 is formed by covering a flange portion 41 of an inner layer container 4 and a flange portion 51 of an outer layer container 5 described later with a coating layer 6.
[0016]
When forming the coating layer 6, the flange portion 21 is stably inclined inward by the outer edges of the flange portion 41 and the flange portion 51 being lifted upward by the resin film forming the coating layer 6. It is formed in a state. The inclination angle θ of the flange portion 21 is 3 to 30 degrees. And In particular, 5 to 20 degrees is preferable. If the tilt angle is too wide, the thermal bonding between the lid 3 and the flange 51 may be insufficient, or the lid 3 may be wrinkled after thermal bonding, and if it is too narrow, the portion of the lid 3 is curved in a concave shape. In some cases, the joint area of the exterior film (shrink film) of the sealed container 1, the bulky part of the wrap part, and the accommodation space for the accessory may not be sufficiently obtained. The inclination angle θ of the upper surface portion 21a of the flange portion 21 refers to the angle between the upper surface portion 21a of the flange portion 21 and the horizontal plane.
[0017]
The flange portion 21 has a cushioning property of 0.1 cm / (2000 gf / cm ² ) To 0.1 cm / (100 gf / cm ² ), Especially 0.1 cm / (1500 gf / cm ² ) To 0.1 cm / (200 gf / cm ² ) Is preferable. If the cushioning property is too low, deformation of the flange portion itself is reduced when the lid body 3 is bonded to the inclined flange portion 21, and contact between the lid body 3 and the flange portion becomes insufficient, thereby obtaining a stable sealing property. It may not be possible. If an excessive load is applied in such a case, there is a risk that the flange portion may collapse and the container may be deformed. Further, the contact state between the flange portion and the lid body is likely to be non-uniform, which may cause uneven adhesion. If the cushioning property is too high, the amount of compression of the flange portion when a predetermined pressure is applied to the flange portion becomes too large, and the restoring force of the flange portion becomes insufficient, causing a problem that the flange portion is crushed or deformed. There is a fear.
Here, the cushioning property in this specification refers to a value obtained as follows. That is, the container body is placed on a horizontal plane, the rigid plate is brought into contact with the upper surface of the flange portion 21 facing obliquely upward, and a load is applied to the rigid plate until the flange portion 21 becomes horizontal. In addition, the member which supports the flange part 21 is arrange | positioned under the flange part 21 so that it may not deform | transform beyond a horizontal state. When a load is further applied while holding the flange portion 21 horizontally, and the upper surface of the flange portion is depressed (compressed) by the load, the unit area (cm ² ) The value that indicates how much it was depressed by the load.
[0018]
The width W of the upper surface portion 21a of the flange portion 21 is preferably 1.5 to 5 mm, particularly preferably 2.0 to 4 mm. If the width is too narrow, the adhesive area with the lid will be reduced, the adhesive strength of the lid will be reduced, barrier properties such as moisture resistance may be reduced, and the strength of the flange may also be reduced, and the width is too wide In some cases, the bonding area between the cover and the lid becomes large, the adhesive strength becomes too large, making it difficult to peel off the lid, and the flange portion itself may be deformed when peeled off.
[0019]
As shown in FIG. 2, the container body 2 is composed mainly of an inner layer container 4 and an outer layer container 5 having a higher density than the inner layer container 4 (in the present specification, density refers to bulk density). It is a mold container. The container body 2 has a coating layer 6 that covers the inner surface and the flange portion 21.
[0020]
The inner layer container 4 is a pulp mold container having a flange portion 41, and is a container that imparts the cushioning property to the flange portion 21 and the predetermined heat insulation property to the container body 2. The inner layer container 4 has a level difference 42 and a level difference 43 for stacking on the inner surface of the container.
[0021]
The inner layer container 4 has a density of 0.05 to 0.5 g / cm. ^Three In particular, 0.1 to 0.4 g / cm ^Three It is preferable that If the density is too high, the heat insulating property is lowered or the container becomes heavy, and if the density is too low, the gripping strength and compressive strength of the container are lowered. Here, the density of the inner layer container 4 is determined from the thickness, area, and weight of the cut inner layer. In addition, the density of the bottom part of the inner layer container 4 is 0.6-1.5 g / cm when heat insulation is not required. ^Three It can also be.
The inner layer container 4 has a density of the flange portion 41 of 0.1 to 0.6 g / cm. ^Three , Especially 0.2-0.5g / cm ^Three It is preferable that If the density of the flange portion 41 is too high, the cushioning property may be deteriorated and the thermal bonding between the lid 3 and the flange portion 21 may not be successful. If the density of the flange portion 41 is too low, the surface smoothness of the flange portion may be reduced. In some cases, the strength of the flange portion itself decreases, the flange portion deforms when the lid body 3 is peeled off, and the lid body partially peels off.
[0022]
The inner layer container 4 preferably contains bulky treated pulp as a pulp component. The amount of bulky treated pulp contained in the inner layer container 4 is preferably 10 to 90 wt%, more preferably 20 to 80 wt%, and most preferably 30 to 70 wt% in the pulp components constituting the inner layer container 4. When the blending amount of the bulky treated pulp in the pulp component is less than 10 wt%, the bulkiness is lowered and the cushioning property of the flange part and the heat insulating property of the container are lowered. Decrease or increase the amount of binder used. Here, the bulky treated pulp used for the inner layer container 4 refers to a pulp fiber that has been curled or hydrophobized by a bulky treatment such as a crosslinking treatment or mercerization treatment, or the rigidity of the fiber itself has been improved. As the cross-linked pulp, commercially available curd fibers (for example, “HBA” manufactured by U.S. Warehauser), and as the mercerized pulp, commercially available mercerized pulp (for example, “POROSAUIE”, “ULTRANIER,” manufactured by Rayonnia) are used. "SULFATE").
[0023]
The cross-linked pulp, mercerized pulp or bulky treated pulp can be used alone or in combination of two or more.
For example, the mercerized pulp can be used by mixing with the crosslinked pulp at an appropriate ratio. If the ratio of mercerized pulp to the crosslinked pulp is too high, the mercerized pulp is inferior in bulk compared to the crosslinked pulp, so that the strength of the inner layer container and the moldability (transferability) of the inner surface of the inner layer container are improved. On the other hand, if the amount is too small, flocs of pulp fibers increase and papermaking unevenness is likely to occur.
[0024]
When the cross-linked pulp is used among the bulky treated pulp, it is preferable that the wet curled factor is 0.1 to 1.0, particularly 0.2 to 0.6. If the wet curled factor is too low, the desired bulkiness may not be obtained. If the wet curled factor is too high, the dispersibility in the raw material slurry is deteriorated, and unevenness in the formed product occurs due to unevenness in papermaking, which may reduce the strength and surface properties of the formed product. Here, wet curd factor means that pulp fibers are immersed in pure water at room temperature and then FQA (Fiber Quality Analyzer) is used, and the number of measurement is 1000 or more and the measurement range is 0.5 to 10 mm ((L _A / L _B ) -1) is a value determined by the arithmetic average, and is a numerical value indicating the degree of fiber curving. However, L _A Is the actual pulp fiber length, L _B Is the maximum dimension of the rectangle surrounding the bent pulp fiber.
[0025]
The inner layer container 4 can contain, as the pulp component, pulp fibers that are not subjected to bulk treatment, in addition to the bulk treatment pulp. The pulp fiber is preferably contained in the pulp component in an amount of 10 to 90 wt%, particularly 20 to 80 wt%. When the pulp fiber is less than 10 wt%, the strength of the flange portion and the container is reduced and a lot of paper dust is generated, and the added amount of the binder is increased in order to obtain strength and prevent paper dust. If it exceeds 90 wt%, the proportion of the bulky treated pulp decreases, and the bulkiness is lowered, and the cushioning property of the flange portion and the heat insulating property of the container may be lowered. Examples of the pulp fibers include unbleached or bleached kraft pulp, sulfite pulp, alkali pulp, ground pulp, or thermomechanical pulp of softwood or hardwood. These pulp fibers can be used alone or in admixture of two or more at an appropriate ratio. In particular, by mixing two or more kinds, pulp fibers having various fiber length distributions can be prepared.
[0026]
The pulp fiber preferably has a CSF (Canadian Standard Freeness) of 200 to 700 ml, particularly 300 to 600 ml. If the CSF is too low, the drainage may be reduced, and the paper making time and drying time may be prolonged. If the CSF is too high, paper making unevenness will be remarkable, resulting in uneven thickness in the resulting molded product, and surface properties of the molded product. May decrease.
[0027]
The average fiber length of the pulp fibers not subjected to bulky treatment is preferably 0.4 to 5 mm, particularly preferably 0.5 to 3 mm. When the average fiber length of the pulp fiber is too short, the entanglement with the bulky treated pulp is reduced, so that the strength of the obtained molded product is lowered and a large amount of paper powder is easily generated. On the contrary, if the average fiber length is too long, the entanglement with the bulky treated pulp becomes too large, so that the flocs become large and papermaking unevenness is likely to occur, resulting in uneven thickness in the obtained molded product, and the surface property also decreases. There is a case.
[0028]
Any of the pulp fibers of wood pulp and non-wood pulp can be used for the bulky treated pulp and the pulp fiber used as the pulp component of the inner layer container 4. Further, any pulp fiber of virgin pulp and waste paper pulp can be used. These pulp fibers can be used alone or in admixture of two or more at an appropriate ratio.
[0029]
The inner layer container 4 may contain 0.2 to 10 wt% of a bulking agent. By including a bulking agent within these ranges, bulkiness can be obtained more stably.
Examples of the bulking agent include “KB115” and “KB85” manufactured by Kao Corporation, and among these, “KB115” is preferable because it can suppress bulkiness and obtain bulkiness. .
[0030]
The inner layer container 4 may contain additives for the inner layer such as a dispersant, a pigment, a fungicide, a sizing agent, a paper strength enhancer, a water resistance agent, and an adhesive in an appropriate ratio as necessary.
[0031]
The outer layer container 5 is a container that mainly gives strength to the container body 2 outside the inner layer container 4. The outer layer container 5 has a flange portion 51 that constitutes the flange portion 21.
[0032]
The outer container 5 has a density of 0.5 to 1.5 g / cm. ^Three Preferably, 0.6 to 1.2 g / cm ^Three It is more preferable that If the density is too high, the pressure applied to the molded body at the time of dry molding becomes excessive, and the pulp fiber may be discolored or the strength of the pulp fiber itself may be reduced. If the density is too low, the strength and surface properties required for the outer layer container May not be obtained. Here, the density of the outer layer container 5 is determined from the thickness, area, and weight of the cut outer layer container.
[0033]
The density of the outer layer container 5 is preferably 1 to 8 times the density of the inner layer container 4, and more preferably 1.5 to 6 times. If the density of the outer container 5 is too lower than the density of the inner container 4, deformation may occur when the container is gripped, the smoothness of the outer surface may be lowered, and the strength of the flange may be lowered, which is too high. In some cases, the smoothness of the inner surface is lowered, or the strength of the inner surface is lowered and the inner surface is crushed when the resin film is stretched to form the coating layer as described later.
[0034]
Examples of the pulp fibers constituting the outer layer container 5 include unbleached or bleached kraft pulp, sulfite pulp, alkali pulp, ground pulp, and thermomechanical pulp. Among these, bleached kraft pulp of conifers and hardwoods is particularly preferable from the viewpoints of moldability, whiteness, surface properties of the molded body, and strength. These fibers can be used alone or in admixture of two or more at an appropriate ratio.
[0035]
The outer layer container 5 may contain additives for outer layers such as a dispersant, a pigment, a fixing agent, an antifungal agent, a sizing agent, an adhesive, and a paper strength enhancer as necessary.
[0036]
A resin film is preferably used for the covering layer 6. Examples of the resin film include thermoplastic resins such as polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate, polyamide resins such as nylon, polyvinyl resins such as polyvinyl chloride, and styrene resins such as polystyrene. Examples thereof include biodegradable resin films such as films, modified polyethylene terephthalate, and aliphatic polyesters. Among these, polyolefin resins are preferable in terms of production cost, moldability, and the like, and biodegradable resin films are preferable in terms of environmentally friendly disposal. These resin films can be used alone or in a laminate of two or more for the coating layer 6.
[0037]
As shown in FIG. 1A, the lid 3 has a curved portion 30 that curves in a concave shape. The curved portion 30 has a ratio (d / L) between the depth d of the most recessed portion and the maximum dimension (diameter in this embodiment) L of the outer edge portion of the flange portion 21 of the container main body 2 to 0.005 to. It is preferable to seal so that it may become 1, and it is more preferable to seal so that it may become 0.01-0.05. If the ratio (d / L) is too small, it will not be possible to secure a bulky portion of the outer film (shrink film) of the sealed container 1 or a bulky portion of the wrap portion, or a storage space for accessory items. It will be greatly curved or wrinkled, resulting in poor appearance.
[0038]
The depth d of the most recessed portion of the curved portion 30 is preferably 1 to 5 mm, particularly preferably 1.5 to 4 mm. If the dent is too shallow, it is not possible to secure a bulky part of the outer film (shrink film) of the sealed container 1 or a bulky part of the wrap part or an accessory storage space, and if the dent is too deep, the lid Is greatly curved and looks bad.
[0039]
As the lid 3, an ordinary sheet-like material conventionally used for sealing a paperboard or a resin cup container can be used without particular limitation. As a material of the lid 3, for example, an aluminum multilayer film having a three-layer structure of paper layer / aluminum layer / synthetic resin layer is preferably used.
[0040]
Next, the manufacturing method of the said sealing container 1 is demonstrated.
In the manufacturing method of the said sealing container 1, first, the pulp mold container 45 which comprises the container main body 2 as shown in FIG. 3 is manufactured. The pulp mold container 45 is manufactured by individually making papermaking bodies for the inner layer container 4 and the outer layer container 5 and combining them.
[0041]
As shown in FIGS. 4 (a) and 4 (b), the papermaking portions 140 and 150 are formed of a convex elastic body, and the papermaking portions 4 'and 5' are formed in predetermined shapes. The papermaking molds 14 and 15 covered with a synthetic resin net (not shown) having a mesh size and a wire diameter of 1 are used, respectively.
[0042]
As shown in FIG. 4A, the papermaking portion 140 of the papermaking mold 14 has a flange portion 141 and has a predetermined taper angle and tapers toward the tip portion. A fine papermaking portion 143 that is further tapered through a step 142 is provided at the tip of the papermaking portion 140.
[0043]
The length of the fine papermaking portion 143 is longer than that of the thin molding portion 171 of the male die 17 of the molding die 16 described later in a state before elastic deformation.
[0044]
When the papermaking mold 14 is combined with the female mold 18 of the molding mold 16 described later, the outer peripheral surface of the convex portion of the papermaking section 140 and the inner peripheral surface of the concave section 180 of the female mold 18 in a state before elastic deformation. Are provided so that a desired gap is formed therebetween, and the length of the convex portion is longer than the depth of the concave portion 180 of the female die 18. Thus, as will be described later, the papermaking mold 14 is combined with the female mold 18 (see FIG. 4E), and the papermaking portion 140 is elastically deformed when the papermaking body 4 ′ is disposed in the female mold 18 of the molding die 16. The papermaking body 4 ′ is pressed against the inner surface of the recess 180 of the female mold 18 while the papermaking body can be dehydrated and molded into a desired shape.
[0045]
A large number of gas-liquid flow passages 144 opened on the outer surface are provided inside the papermaking section 140. These gas-liquid flow paths 144 are densely (many) disposed in the fine papermaking portion 143. As a result, a large amount of solid content in the slurry is deposited on the portion of the net that covers the fine papermaking portion 143, and the papermaking body 4 'is placed in the female die 18 of the forming die 16 and dehydrated as described later. Sometimes (see FIG. 4 (e)), a desired basis weight difference is obtained in the body of the papermaking 4 '. Moreover, since the fine papermaking part 143 is provided, even if it increases the accumulation amount of the solid content in a slurry, when making it insert in the recessed part 180 of the female type | mold 18, there is no possibility that the papermaking body 4 'will be damaged.
[0046]
As shown in FIG. 4B, the papermaking portion 150 of the papermaking mold 15 has a flange portion 151 and has a predetermined taper angle and tapers toward the tip portion. A number of gas-liquid flow passages 152 that are open on the outer surface are provided inside the papermaking unit 150. A gas-liquid flow passage 152 is disposed substantially uniformly at a portion corresponding to the body portion of the papermaking body 5 ′ in the papermaking section 150 so that the solid content in the slurry is deposited substantially uniformly. Thereby, when the papermaking body 5 ′ is dehydrated and dried as described later, the body portion of the papermaking body 5 ′ is dewatered and molded with a substantially uniform basis weight.
[0047]
When the papermaking mold 15 is combined with the female mold 18 of the mold 16 (see FIG. 4D), the outer peripheral surface of the convex portion of the papermaking section 150 and the concave portion of the female mold 18 are in a state before elastic deformation. A desired gap is formed between the inner peripheral surface of 180 and the length of the convex portion is longer than the depth of the concave portion 180 of the female mold 18. As a result, the papermaking mold 15 is combined with the female mold 18, and the papermaking body 5 ′ is pressed against the inner surface of the recess 180 of the female mold 18 while elastically deforming the papermaking portion 150 to dry-mold the papermaking body 5 ′ in a desired shape. It can be done.
[0048]
The material of the papermaking portions 140 and 150 in the papermaking molds 14 and 15 is preferably an elastic body such as silicone rubber from the viewpoint of heat resistance and corrosion resistance.
[0049]
In this embodiment, before combining the papermaking body 4 ′ and the papermaking body 5 ′, the papermaking body 5 ′ is dehydrated and further dry-molded. For dewatering molding and dry molding of the papermaking body 5 ′, a female mold 19 for dewatering molding (see FIG. 4C) and a female mold 18 of the molding die 16 described later (see FIG. 4D) are used.
[0050]
The female mold 19 is made of a metal such as aluminum having rigidity, and has a recess 190 having a shape corresponding to the outer shape of the outer container 5. A gas-liquid flow passage 191 that opens in the recess 190 is provided inside the female die 19.
[0051]
As a mold for dry-molding the papermaking body 4 ′ and the papermaking body 5 ′, a molding die 16 composed of a male die 17 and a female die 18 is used as shown in FIG. As the male mold 17 and the female mold 18, a metal mold such as aluminum having rigidity is used.
[0052]
The male mold 17 has a convex molded portion 170 corresponding to the inner surface shape of the inner layer container 4. A thin molding portion 171 having a reduced diameter corresponding to the stacking step 43 of the inner layer container 4 is provided at the distal end portion of the molding portion 170. The length of the thin molding part 171 is shorter than the length of the fine papermaking part 143 of the papermaking mold 14.
[0053]
A plurality of gas-liquid flow passages (not shown) opened in a slit shape on the outer peripheral surface are provided inside the molding unit 170, and when the papermaking bodies 4 ′ and 5 ′ are combined through these gas-liquid flow passages. Can be dehydrated and exhausted. Further, a cartridge heater (not shown) is disposed inside the molding unit 170 so that heating can be performed from the outer surface of the molding unit 170.
[0054]
The female mold 18 has a recess 180 corresponding to the outer shape of the outer layer container 5 (pulp mold container 45). A cartridge heater 181 is disposed inside the female mold 18. Further, the female mold 18 is provided so that a predetermined clearance is formed between the convex portion of the molding part 170 and the concave part 180 when combined with the male mold 17. It is preferable to use a female mold 18 that does not have an exhaust hole that opens on the inner surface of the recess 180 so as not to leave behind on the outer surface of the pulp mold container 45, but when it is desired to shorten the dry molding time. The one having an exhaust hole can also be used.
[0055]
When the papermaking body 4 ′ and the papermaking body 5 ′ are made, as shown in FIGS. 4A and 4B, the papermaking molds 14 and 15 are immersed in pools P4 and P5 each having a predetermined slurry. Then, the slurry is sucked through the gas-liquid flow passages 144 and 152 to deposit the solid content in the slurry on the net.
[0056]
As the slurry used for papermaking of the papermaking body 4 ′, it is preferable to use a slurry having a pulp fiber concentration of 0.1 to 2.0 wt%. Although there is no restriction | limiting in particular in a dispersion medium, It is preferable to use water or white water as a dispersion medium from the point of handleability and production cost. Moreover, the said additive for inner layers can be contained in a slurry in a suitable ratio as needed.
[0057]
The slurry 4 ′ preferably contains 0.01 to 0.5 wt% of a dispersant with respect to the pulp component. If the dispersant is less than 0.01 wt%, a sufficient dispersing effect cannot be obtained, and if it exceeds 0.5 wt%, the papermaking time becomes long, and the net or mold becomes dirty.
Examples of the dispersant include various surfactants, polyethylene oxide or a derivative thereof, and among these, polyethylene oxide is preferable from the viewpoint of less foaming and easy handling of the slurry.
[0058]
As a slurry used for papermaking of the papermaking body 5 ′, it is preferable to use a slurry having a pulp fiber concentration of 0.1 to 2.0 wt%. Although there is no restriction | limiting in particular in a dispersion medium, It is preferable to use water or white water as a dispersion medium from the point of handleability and production cost. In addition, the outer layer additive may be included in the slurry at an appropriate ratio, if necessary.
[0059]
From the viewpoint of improving the strength and the smoothness of the surface, the papermaking body 5 ′ is dehydrated in advance and dried to be densified before being overlapped with the papermaking body 4 ′. Specifically, after papermaking for a predetermined time, the papermaking mold 15 is pulled up from the slurry, and as shown in FIG. 4C, the papermaking mold 15 is abutted against the female mold 19 for dehydration molding together with the papermaking body 5 ′. Then, the wet papermaking body 5 ′ is pressed by the papermaking portion (the flange 151 portion and the convex portion) 150 of the papermaking mold 15 to perform dehydration molding. When the papermaking body 5 ′ is dehydrated, the liquid content of the papermaking body 5 ′ is sucked through the gas-liquid passages 152 and 191 of the papermaking mold 15 and the female mold 19 and discharged to the outside.
[0060]
After dewatering the papermaking body 5 ′ to a predetermined moisture content, the papermaking body 5 ′ was moved together with the papermaking mold 15 as shown in FIG. 4 (d), and the papermaking mold 15 was heated to a predetermined temperature by the heater 181. Combine with the female mold 18 of the mold 16. The water content of the papermaking body 5 ′ at this time is preferably 60 to 80%, particularly 65 to 75% from the viewpoints of shortening the drying time, smoothness of the surface, and prevention of scorching and discoloration.
[0061]
Then, the papermaking section 5 of the papermaking mold 15 is dry-molded while pressing the wet papermaking body 5 ′ against the recess 180 and the opening edge thereof, and the papermaking body 5 ′ is dried and densified. When the papermaking body 5 ′ is dried, the liquid component (vapor) of the papermaking body 5 ′ is sucked through the gas-liquid passage 152 of the papermaking mold 15 and discharged to the outside.
[0062]
The mold temperature (temperature of the female mold 18) at the time of drying the papermaking body 5 ′ is 110 to 250 ° C., particularly 120 to 230 ° C. in terms of prevention of scorching due to drying, drying efficiency, surface smoothness, and the like. Is preferred. After the papermaking body 5 ′ is dried, the papermaking body 5 ′ is transferred from the papermaking mold 15 to the female mold 18. After completion of delivery, the papermaking mold 15 is retracted. At this time, the compressed air can be purged through the gas-liquid flow passage 152 in the paper making section 150 and separated quickly.
[0063]
Next, as shown in FIG. 4 (e), the papermaking body 4 ′ is overlaid from above the papermaking body 5 ′ after dehydration and drying disposed in the female mold 18. At this time, the papermaking body 4 ′ is not removed from the papermaking mold 14, and the papermaking mold 14 is directly butted against the female mold 18. Then, the papermaking body 4 ′ in the wet state is pressed against the concave portion 180 by the papermaking portion (the flange 141 portion and the convex portion) 140 of the papermaking mold 14, and dewatering is performed while elastically deforming the papermaking portion 140. While 'dehydrated and molded', it is brought into close contact with the papermaking body 5 '. The mold temperature at this time (temperature of the female mold 18) is more preferably 150 to 250 ° C., particularly 170 to 230 ° C., from the viewpoint of shortening the drying time and preventing scorching and discoloration.
[0064]
After the papermaking body 4 ′ and the papermaking body 5 ′ are sufficiently adhered, the papermaking mold 14 is raised to separate the papermaking body 4 ′ from the papermaking mold 14. At this time, the compressed air can be purged through the gas-liquid flow passage 144 in the paper making section 140 and separated quickly. The papermaking mold 14 separated from the papermaking body 4 'is retracted.
[0065]
Next, as shown in FIG. 4 (f), the male mold 17 is butted against the female mold 18, and the combined papermaking body 4 ′ and papermaking body 5 ′ are dry-molded.
[0066]
In dry molding, the male mold 17 and the female mold 18 are heated to a predetermined temperature with their respective heaters, and the papermaking body 4 ′ and the papermaking body 5 ′ are integrated with a predetermined pressing force. Further, at the time of dry molding, the moisture of the papermaking body 4 ′ is discharged outside as steam through the gas-liquid flow passage of the male mold 17.
[0067]
The flange portions 41 ′ and 51 ′ of the papermaking bodies 4 ′ and 5 ′ are joined and integrated by a pressing force during dry molding. The male mold 17 and the female mold 18 are provided with a predetermined clearance also in the flange portion. Adhesives can also be used for joining the flange portions 41 'and 51' in terms of increasing the adhesive strength. As food containers, natural adhesives such as starch and carboxymethylcellulose, and synthetic water-soluble adhesives such as PVA Is preferably used.
[0068]
The mold temperature (temperature of male mold 17 and female mold 18) at the time of dry molding is 150 to 250 from the viewpoint of preventing scorching from each papermaking body 4 'and 5' and maintaining high drying efficiency. It is preferable that it is 170 degreeC, especially 170-230 degreeC.
[0069]
When the papermaking bodies 4 ′ and 5 ′ are dried to a predetermined moisture content and the papermaking body 4 ′ and the papermaking body 5 ′ are closely integrated, the dry molding is finished. Then, the pulp mold container 45 is removed by separating the male mold 17 and the female mold 18. And the process of trimming etc. is performed as needed and the manufacture of the pulp mold container 45 is completed.
[0070]
Next, the coating layer 6 is formed so as to cover the inner surface of the pulp mold container 45 (the inner surface of the inner layer container 4) and the flange portions 41 and 51.
The covering layer 6 can be formed by a conventional method such as vacuum forming using a resin film, pressure forming, or the like. In the case of vacuum forming, for example, as shown in FIG. 5 (a), the vacuum suction path 70 and the band heater are approximately the same size as the female mold 18 (see FIG. 4 (d)) used in the dry forming step. A vacuum forming die 7 having 71 and a plug 8 having a heater 80 are used. As shown in FIG. 5 (b), the vacuum forming die 7 is provided with a predetermined clearance between a portion 72 facing the lower surface of the flange of the pulp mold container 45 and the flange portion. Also, a suction port of the vacuum suction path 70 is provided.
[0071]
Then, as shown in FIG. 5A, the pulp mold container 45 is set in the vacuum mold 7, and the resin film 60 is set so as to close the opening of the pulp mold container 45. Further, the plug 8 heated from above is brought into contact with the resin film 60 and the resin film 60 is pushed into the vacuum mold 7 while the air permeability of the pulp mold container 45 is utilized and the pulp mold is passed through the vacuum suction path 70. The inside of the container 45 is evacuated, and the resin film 60 is brought into close contact with the inner surface of the pulp mold container 45.
[0072]
At this time, as shown in FIG. 5 (b), the resin film 60 that has been heated and softened in advance is brought into close contact with the bottom surface of the flange portion of the pulp mold container 45, and the resin when the plug 8 is pushed in. The outer edge of the flange is pulled upward by the tension applied to the film 60. Thereby, the flange part 21 of the container main body 2 obtained as mentioned above is inclined inside. Then, the excess resin film 60 is trimmed to complete the manufacture of the container body 2.
[0073]
Next, after a desired content (not shown) is accommodated in the container body 2, as shown in FIG. 6 (a), a plate-like pressing element 90 and a female provided with a heater (not shown). The container body 2 is accommodated in the female mold 91 using the mold 9 provided with the mold 91.
[0074]
Then, the lid 3 is disposed so as to close the opening 20 of the container body 2. In addition, the lid body 3 has an outer edge substantially corresponding to the outer edge when the flange portion 21 becomes flat.
[0075]
Next, as shown in FIG. 6B, the pressing member 90 heated to a predetermined temperature is lowered and pressed from above until the flange portion 21 disappears and becomes substantially flat. In this way, even when the flange portion 21 is pressed with the heated presser 9 and the inclined flange portion 21 is deformed so as to be flat, the flange portion 21 has cushioning properties. Even if the upper surface portion 21a of the flange portion 21 can follow the deformation and the flange portion 21 is deformed so that it undulates or wrinkles are formed on the flange portion 45 of the inner layer container 4 (see FIG. 1B). While removing the deformation and wrinkles, the lid 3 can be securely adhered to the upper surface portion 21a of the flange portion 21 over the entire surface, and a good sealing property can be obtained.
[0076]
When the pressing member 9 is retracted upward after being pressed for a predetermined time, the flange portion 21 is restored to an obliquely inclined state by its elastic restoring force, and the lid body 3 is curved in a concave shape to form a curved portion 30. Then, the sealed container 1 (see FIG. 1A) is manufactured.
[0077]
Since the flange 21 of the container body 2 has cushioning properties as described above, the sealed container 1 of the present embodiment is made of paperboard even when the lid 3 is bonded to the upper surface portion 21a of the flange portion 21. Compared with the flange portion of the cup container, the upper surface portion 21a of the flange portion 21 can follow the deformation of the flange portion 21 accompanying the bonding. Therefore, unlike the paperboard cup container, even when the flange portion 21 is provided so as to be inclined and deformable, or when the upper surface portion 21a of the flange portion 21 has undulations or wrinkles, the lid 3 Can be bonded to the flange portion with high sealing performance.
[0078]
Further, since the lid 3 has the curved portion 30, the article can be accommodated when the article is attached separately from the contents accommodated in the container body, or the outside of the sealed container is further wrapped with a shrink film. It is possible to store a bulky portion such as a joining portion or a wrap portion of the film at the time, and there is no trouble even when vertically stacking at the time of display or packing.
[0079]
In addition, since the container body 2 is formed mainly of a pulp mold container 45 composed of a low-density inner layer container 4 and a high-density outer layer container 5, it is thin and has excellent heat insulation and strength.
[0080]
The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.
[0081]
For example, in the sealed container of the present invention, the coating layer is preferably provided as a film as in the above-described embodiment, but the coating layer can also be provided by applying a paint containing the resin component of the resin film.
[0082]
Moreover, in the said embodiment, after making papermaking 5 ', it spin-dry | dehydrated, it was made to unite with papermaking 4 after drying, but the dehydration process of papermaking body 5' can also be skipped. Further, the orientation of the papermaking mold and the various male and female molds used in the manufacturing process can be appropriately changed. For example, each papermaking body can be made by turning the papermaking mold upward in the papermaking step, holding the raw material slurry around the papermaking portion, and sucking the slurry. Also, the female mold used when drying the papermaking body 5 ′ and the female mold used when combining the papermaking bodies 4 ′ and 5 ′ and drying can be performed separately. Furthermore, you may provide the inclination of a flange part with a type | mold at the time of shaping | molding of a container.
[0083]
There is no restriction | limiting in particular in the use of the sealing container of this invention, and there is no restriction | limiting in particular also in the content accommodated. As an application of the sealing container, for example, in addition to the instant cup noodles of the above embodiment, ice cream, various foods and foods and drinks such as confectionery, seasonings, medicines, cosmetics, detergents, and other storage containers, A container in a form in which an article is attached separately from the contents stored in the container main body can be mentioned.
[0084]
【The invention's effect】
According to the present invention, the lid is excellent in adhesiveness and can contain the article when the article is attached separately from the contents contained in the container body, or the outside of the sealed container is further wrapped with the shrink film It is possible to store bulky parts such as joints and lap parts of the film when it is done, and it is possible to manufacture a sealed container that does not hinder vertical stacking during display or packaging A pulp mold container and a sealed container using the same are provided.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an embodiment in which a sealed container of the present invention is applied to a food container, wherein (a) is an elevation view partly broken and (b) is a diagram of (a). It is a partial enlarged view.
FIG. 2 is a half sectional view showing a container body in the sealed container of the embodiment.
FIG. 3 is a half cross-sectional view showing a pulp mold container constituting a container body in the sealed container of the embodiment.
4A and 4B are diagrams schematically showing a manufacturing process of the sealed container according to the embodiment, in which FIG. 4A is a view showing a paper making process of the inner layer container paper making process, and FIG. 4B is an outer layer container paper making process. The figure which shows a papermaking process, (c) is a figure which shows the dehydration molding process of the papermaking body for outer-layer containers, (d) is a figure which shows the dry-molding process of papermaking bodies for outer-layer containers, (e) is the papermaking body for inner-layer containers, The figure which shows the coalescing process of the papermaking body for outer layer containers, (f) is a figure which shows the dry molding process of a pulp mold container.
5A and 5B are diagrams schematically showing a manufacturing process of the sealed container according to the embodiment, in which FIG. 5A is a cross-sectional view showing a state where a coating layer is formed, and FIG. 5B is a main part of FIG. It is an enlarged view.
6A and 6B are diagrams schematically illustrating a manufacturing process of the sealed container according to the embodiment, where FIG. 6A is a partial cross-sectional view illustrating a state in which a lid is disposed above the container body, and FIG. 6B is a presser. It is a fragmentary sectional view which shows the state which presses the cover body to the flange part.
[Explanation of symbols]
1 Sealing container
2 Container body
20 mouths
21 Flange
21a Upper surface part
3 lid
30 Curved part
4 Inner container
41 Flange
45 Pulp mold container
5 outer container
51 Flange
6 Coating layer
7 Vacuum forming mold
8 plugs
9 Presser

Claims (6)

A pulp mold container used for a sealing container in which a lid is curved and bonded in a concave shape to be sealed,
An inner layer container and an outer layer container having a higher density than the inner layer container;
The peripheral portion of the mouth portion, provided with a flange portion facing and obliquely upward have a cushioning property, together with the upper surface portion where the cover body is bonded is inclined 3-30 degrees inward in the flange portion, the The pulp mold container whose density of the flange part of the said inner layer container which forms a flange part is 0.1-0.6 g / cm < ³ >. The cushioning 0.1cm / (2000gf / cm ²⁾ of the flange portion ~0.1cm / (100gf / cm ²⁾ molded pulp container according to claim 1, wherein a.   The pulp mold container according to claim 1 or 2, wherein bulky treated pulp is contained in the pulp component of the inner layer container.   The pulp mold container in any one of Claims 1-3 which contain the bulking agent in the pulp component of the said inner layer container.   The pulp mold container in any one of Claims 1-4 which has a coating layer which covers an inner surface and the said flange part. The pulp mold container according to any one of claims 1 to 5 is used as a container main body, the contents are accommodated in the container main body, a lid is bonded to the upper surface portion of the flange portion, and the mouth portion is sealed. A sealed container,
A sealed container having a curved portion in which the lid body is curved in a concave shape.

Images