KR20090028570A - Heat-sealable wrapping paper and heat-sealed packages - Google Patents

Abstract

[PROBLEMS] To provide a wrapping paper which has a paper-like feeling and waterproofness and which can be heat-sealed on both sides and little breaks even when held in the hands. [MEANS FOR SOLVING PROBLEMS] A wrapping paper waterproofed either by laminating a layer (2) of a blend paper composed of pulp fiber and a thermoplastic resin fiber with a waterproof layer (3) made of a thermoplastic resin on one side of the layer (2) or by imparting waterproofness to such a blend paper with a sizing agent or the like, wherein the basis weight of the blend paper is adjusted to 25 to 55g/m2 and the contents of pulp fiber and the thermoplastic resin fiber in the layer (2) are adjusted to 50 to 75wt% and 50 to 25wt% respectively.

Description

Heat sealable packaging and heat seal packaging {HEAT-SEALABLE WRAPPING PAPER AND HEAT-SEALED PACKAGES}

The present invention relates to a heat sealable wrapping paper and a heat seal package.

For example, roll-shaped paper products, such as a toilet paper roll and a kitchen paper roll, etc., are generally sold to a consumer in plural number as one unit (for example, refer patent documents 1 and 2).

In this case, it is common that each product is packaged by the thermoplastic resin film 10, such as a polyethylene film, in the state laminated | stacked two or more as shown in FIG. As the packaging form, as shown in the drawing, the film 10 is folded and wrapped in accordance with the external shape of the package object 11, and in addition to caramel packaging for heat-sealing overlapping portions of the film, gusset packaging, pillow packaging, and the like. Is adopted. If necessary, a handle 12 formed of the same material as that of the packaging material is attached to the outer surface of the package by the heat seal.

In a packaging material using such a thermoplastic resin film, there is a risk of breakage in the heat seal portion, or there is also a problem such as an increase in cost when a thick film is used to avoid this. Moreover, from the viewpoint of resource recycling, using a thermoplastic resin film has a drawback that it is difficult to reuse materials.

In order to solve this, the packaging material which laminated the thermoplastic resin layer on the single side | surface of a paper base material is also proposed (refer patent document 3). Such a packaging material is a very preferable packaging material in that it has a texture as paper, is waterproof, and a heat seal is also possible.

However, this prior art has a problem that it is not possible to heat seal the sheets with each other, and the packaging form is limited.

In terms of the strength of the packaging material, the packaging material may be torn when the product is held in front of the store.

Patent Document 1: Japanese Utility Model Registration No. 3010719

Patent Document 2: Japanese Unexamined Patent Publication No. 2005-153959

Patent Document 3: Japanese Unexamined Patent Publication No. 63-12410

Then, the main subject of this invention is providing the wrapping paper which has the texture as paper, is waterproof, and a heat seal is possible at both front and back, and suppresses the tear at the time of a hand.

This invention which solved the said subject is as follows.

<Invention of Claim 1>

A heat sealable wrapping paper characterized in that it is a mixed paper made of pulp fibers and thermoplastic resin fibers.

<Invention of Claim 2>

The heat-sealable wrapping paper according to claim 1, wherein a waterproof layer made of a thermoplastic resin is laminated only on one side of the mixed paper.

<Invention of Claim 3>

A heat sealable packaging paper according to claim 1, wherein a size agent or a water repellent agent is provided to the mixed paper.

(Effects of the Invention of Claims 1 to 3)

The main feature of the present invention is not only having waterproofness but also blended thermoplastic resin fibers or one side by laminating a waterproof layer made of thermoplastic resin on one side of mixed paper or adding a size agent, a water repellent, etc. to the mixed paper. It has a double-sided heat sealability by the thermoplastic resin layer laminated | stacked on it, and has a function similar to the conventional film packaging, having a texture of paper.

Although lamination of the thermoplastic resin layer on both sides of the paper base material can impart waterproofness and heat sealability on both sides of the front and back, in that case, the texture as paper may be damaged or the paper may not be disposed of as paper. On the other hand, in the present invention, at least one surface of the paper is exposed, and there is no fear that the texture as the paper is damaged.

<Invention of Claim 4>

The rice cake in the said mixed paper is 25-55 g / m <2>,

The content rate of the pulp fiber in the said mixed paper is 50-75 weight%,

The content ratio of the thermoplastic resin fiber in the said mixed paper sheet is 50-25 weight%, The heat sealable wrapping paper in any one of Claims 1-3 characterized by the above-mentioned.

(Effects and Effects of the Invention of Claim 4)

In particular, by setting the kneading ratio within the range described in this section, it is balanced in both waterproofness, heat sealability, rupture strength, suppression of tearing at hand, and processing titration.

<Invention of Claim 5>

50 to 75% by weight of pulp fibers and 50 to 25% by weight of thermoplastic resin fibers are kneaded, and a sizing agent is added to use mixed paper having 25 to 55 g / m2 of flat rice,

A heat seal package, characterized in that the sealing portion of the object is sealed with a heat seal while the article is wrapped.

(Effects and Effects of the Invention of Claim 5)

A heat seal package excellent in practical use is obtained.

 <Invention of Claim 6>

The said thermoplastic resin fiber is a composite fiber of the core-in-sheath structure whose core is polypropylene and sheath is polypropylene whose melting point is lower than a core, The heat seal of Claim 6 characterized by the above-mentioned. Package.

(Effects and Effects of the Invention of Claim 6)

For the heat seal, it is possible to use a mixed paper with polyethylene fiber or a mixed paper made of a composite fiber having a sheath structure in which the core is polypropylene and polyethylene having a lower melting point than that of the initial seam. Is not necessarily enough. This is considered to be because the strength of polyethylene itself is low and the strength of polyethylene itself is still expressed as long as polyethylene is used as a binder even when composite fibers are used because the strength of polyethylene itself is low.

On the other hand, when the core is made of polypropylene and the composite fiber having a core structure having a polypropylene having a lower melting point than that of the core, the strength of the polypropylene itself is higher than that of the polyethylene, and the adhesive strength of the polypropylene of the ultra As a result, as a result of bonding with the polypropylene of the core which still does not melt even if the second polypropylene is melted, it is considered that the yarn strength is high as a whole, and as shown in Examples described later, the yarn strength is actually high. High enough is obtained.

<Invention of Claim 7>

The heat seal package according to claim 5 or 6, wherein the size agent is an alkyl ketene dimer.

(Effects of the invention described in claim 7)

Although waterproofing property can be provided to a package by providing the waterproof layer by a thermoplastic resin in the inner surface side of a package, it is hard to say that it is necessarily preferable from a viewpoint of the appearance which is made of paper, since it can know clearly that it is a laminated paper when it opens. Moreover, in the case of thin paper products, such as a toilet paper roll, as a to-be-packed article, it adhered to the waterproof layer by static electricity etc. in the packaging process, and the problem in the packaging process was discovered. On the other hand, it was found that by using the size agent in external application, the same water repellency or waterproofness as in the case of providing a waterproof layer can be imparted. In particular, alkylketene dimer (AKD) exhibits excellent water repellency or water resistance in the blended composition of the mixed paper of the present invention as compared with other size agents.

[Effects of the Invention]

As described above, according to the present invention, it has advantages such as being able to exhibit water repellency or waterproofness while having a texture as paper, and to enable a heat seal on both sides of the front and back, and to suppress tearing when picked up.

1 is a cross-sectional view of a wrapping paper according to the present invention.

2 is a perspective view of a toilet paper roll product.

3 is a perspective view of another product.

[Description of the code]

One… . Wrapping paper 2.. Mixed Grass Layer

3... Waterproof layer 10.. Thermoplastic Film

11... Package object 12.. handle

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described in detail, referring an accompanying drawing.

Fig. 1 shows a cross section of a heat sealable wrapper 1 according to the present invention, which has a mixed papermaking layer 2 and, if necessary, a waterproof layer 3 laminated (laminated) only on one side thereof. Have

The mixed papermaking layer 2 is formed by mixing pulp fibers and thermoplastic resin fibers. As pulp, NUKP (softwood bleached kraft pulp), NBKP (softwood bleached kraft pulp), LBKP (softwood bleached kraft pulp), BCTMP (bleach chemical hot air pulp), TMP (thermomechanical pulp), GP (woodwood pulp), etc. It can be used without limitation, and as thermoplastic resin fibers, PE fibers, PP fibers, PET fibers or composite fibers thereof can be used without particular limitation, but the core is polypropylene, the composite fiber having a sheath structure of polypropylene having a lower melting point than that of the initial core Is preferably. The melting point of the shim in such a PP / PP composite fiber is preferably 150 to 170 ° C, the melting point of seconds to about 120 to 140 ° C, and the temperature difference of the melting point is 25 to 40 ° C for the workability due to the heat seal machine. .

The blending ratio of both fibers can be determined appropriately, but the pulp fibers are more than 50 to 75% by weight (particularly 50 to 65% by weight), and the thermoplastic resin fibers are less than 50 to 25% by weight (particularly less than 50 to 35% by weight). desirable. When the proportion of the thermoplastic resin fibers is too small, the heat seal is inferior. When the proportion of the pulp fibers is too small, the texture as paper may be deteriorated, or when discarded, it may be impossible to dispose of it as paper. From this point of view, it is preferable to include more than 50% by weight of pulp fibers as the entirety of the wrapping paper 1 (even if it includes a waterproofing layer), since waste can be disposed of as paper.

If necessary, vinylon fibers may be blended to improve the (burst) strength of mixed papermaking. As the mixing ratio of vinylon fiber, it is preferable to make 7 weight% an upper limit.

As the thermoplastic resin fibers, those having a fineness of 0.5 to 10 dtex and a fiber length of 2 to 30 mm are preferable. If the fineness is less than 0.5 dtex, the adhesive strength is insufficient and sufficient paper strength is not obtained, and even if the fineness is more than 10 dtex, the number of fibers per unit weight is small and the adhesive strength is lowered, so that sufficient paper strength is not obtained. If the fiber length is less than 2 mm, the adhesion strength is insufficient. If the fiber length is more than 30 mm, the dispersibility in water is deteriorated, and the paper strength is lowered. The more preferable range of fineness is 1-8 dtex, and the more preferable range of fiber length is 3-20 mm. It is also possible to use olefin synthetic pulp that is not cut fiber.

When not providing a waterproof layer by a thermoplastic resin layer, it is preferable to provide waterproofing property to a mixed paper by a size agent and a water repellent agent. The type of sizing and water repellent is irrelevant. Examples of the size agent include alkylketene dimers, styrene acrylic resins, size agents such as rosin, olefin wax-based water repellents, and fluorine-based water repellents. Alkylketene dimers and fluorine-based water repellents have a low coating amount and high water / water repellency effects, but fluorine-based water repellents are expensive due to their high cost. As addition amount of a size agent, it is preferable that it is 2-10 weight% with respect to all the fibers.

As the method for adding the size agent and / or the water repellent agent, external coating is preferable. In the case of internal additives, in order to achieve the target waterproofness, it is necessary to add them in large quantities, and external application is preferable because there are problems in operation such as foaming or dirty machines. It will not specifically limit, if it is external application | coating, such as a size press, a gate roll press, calendar coating, and gravure coating.

As a water repellent, what melt | dissolved the resin of a silicone type, an acryl type, a urethane type, ester type, an oil-based resin, or a monomer can be used, As a specific example, Wax emulsion which emulsified wax, such as a paraffin wax and a natural wax; Synthetic resins such as polyamide resin and polyamine resin; Fluororesins such as polytetrafluoroethylene and polychlorotrifluoroethylene; Silicone resins, such as a polymethyl hydrogen siloxane and a polydimethylsiloxane, are mentioned.

Kneading can be performed by a conventional paper machine, and the size agent and / or water repellent are preferably added as an external additive as described above. In kneading, in addition to the size agent and the water repellent agent, it is also possible to add an intelligence agent and a product yield improving agent as necessary. As the strength agent and the product yield improving agent, polyacrylamide resin, polyamide epichlorohydrin resin, polyethyleneimine and its derivatives, polyethylene oxide, polyamine, polyamide, polyamide polyamine and its derivatives, cationic and amphoteric starches , Organic compounds such as starch oxide, carboxymethylated starch, plant gum, polyvinyl alcohol, and inorganic compounds such as sulfate band, alumina sol, colloidal silica, bentonite, and the like are used in combination.

It is also possible to add a whole material, such as talc, kaolin, calcined kaolin, clay, diatomaceous earth, heavy calcium carbonate, magnesium carbonate, aluminum hydroxide, titanium dioxide, magnesium sulfate, silica, aluminosilicate, bentonite, etc. Organic synthetic fillers, such as a filler, polystyrene particle, and urea formalin resin particle, etc. can also be selected suitably, and can be used together. In addition, additive additives for papermaking, such as dyes, pH preparations, slime control agents, antifoaming agents, and viscous agents, may be appropriately used depending on the application.

The water-proof layer 3 provided as needed is an impermeable layer which consists of thermoplastic resins, such as PE, PP, and PET. The material of the waterproof layer 3 is preferably the same as that of the thermoplastic resin fibers in the mixed papermaking layer 2, but may be different. If the waterproof layer 3 is impermeable, the thickness 3t will not be specifically limited, It is good that it is 6 micrometers or more. Preferably it is 6-20 micrometers. If the thickness is less than 6 µm, the waterproofness is inferior. If the thickness is more than 20 µm, the waterproofness is difficult, but the tearing becomes difficult when opening the wrapping paper.

In production, a known method may be employed, such as after preparing mixed paper using the pulp fibers and thermoplastic resin fibers as a raw material, and then laminating the thermoplastic resin film only on one side of the mixed paper.

As a mixed papermaking paper, it is preferable that rice flat is 25-55g / m <2>. If the flat rice is less than 25 g / m 2, the strength may be insufficient and may be torn when the product after packaging is lifted. In addition, when it is larger than 55g / ㎡, the packaging equipment of the existing thermoplastic resin film can not be used, or even if it can be used, there is a case that the operation performance is deteriorated, such as increasing the heat chamber temperature or reducing the processing speed. In other words, if the mepyeong is too low, the strength is insufficient, if the mepyeong is too high, it becomes difficult to use the packaging equipment of the existing thermoplastic resin film.

As bursting strength (JIS P 8112) of mixed papermaking, 0.90 to 1.95 kgf / cm 2 is preferable. The lower limit is the strength required for the packaging, and when the upper limit is exceeded, the opening becomes difficult, and the cost increases as the wrapping paper.

In the wrapping paper 1 thus constructed, the surface of the waterproof layer 3 to the surface of the waterproof layer 3, the surface of the waterproof layer 3 to the surface of the mixed sheet 2, and the surface of the mixed layer 2, the surface of the mixed layer 2 Good heat seal is exhibited on any of the surfaces. As the packaging form, the caramel packaging, gusset packaging, pillow packaging and the like described above can be adopted.

EXAMPLE

Various packaging papers shown in Table 1 were produced and evaluated for heat sealability, strength, waterproofness, water repellency and processing titration. In that case, the effect based on the effect of the size agent addition and the kind of size agent was investigated. The results are shown in Table 1.

Used pulp fiber (NUKP (softwood unbleached kraft pulp)), thermoplastic fiber (composite fiber: core fiber polypropylene (melting point 165 ° C), superficial polypropylene (melting point 132 ° C) composite fiber of the sheath structure (PP / PP composite fiber) ), Specific examples of the size agent and the water repellent agent are listed in Table 1 and Table 2.

Here, heat seal strength was performed at 170 degreeC which is close to the room temperature at the time of PE film packaging, and real time was performed for 3 second. The test piece width of the yarn strength measurement was 25 mm, and the peel strength was measured by tensilon (TENSILON). Regarding heat sealability, the sheets of the packaging paper were sealed with a heat sealer, and when the seal portion was peeled off, the packaging paper was broken, and the peeling (similar adhesion) and the unsealing were made x. The bursting strength (JIS P 8112) was also measured, and the bursting strength was 0.90 kgf / cm 2 or more, and the lower one was ×. Moreover, as a range of bursting strength, it is preferable that they are 0.90-1.95 kgf / cm <2>. If it is less than 0.90 kgf / cm 2, tearing occurs easily when it is held in the hand, and if it exceeds 1.95 kgf / cm 2, a problem arises that it is difficult to tear when opening the wrapping paper. In terms of waterproofing, an absorbent paper was placed under the wrapping paper, and 1 ml of water colored with an aqueous ink was added dropwise to see the penetration of water into the absorbent paper below. As a result, even if it was left to stand for 1 hour or more, the thing which did not penetrate into water was made into (circle), and the thing which penetrated in less than 1 hour was made into x. In addition to water resistance, water repellency (JAPAN TAPPI NO.68) and heat seal strength were also measured, and the results are shown in Table 2. The water repellency was measured according to JAPAN TAPPI NO.68. In addition, about pavement processing aptitude, when the fine evaluation increased, the thing which must raise the thread temperature at the time of packaging processing or lengthen the heating time was made into x.

INDUSTRIAL APPLICABILITY The present invention can be suitably used as a wrapping paper for wrapping a rolled paper product such as a toilet paper roll or a kitchen paper roll.

Claims (7)

A heat sealable wrapping paper characterized in that it is a mixed paper made of pulp fibers and thermoplastic resin fibers. The method of claim 1, A heat sealable wrapping paper characterized by laminating a waterproof layer made of a thermoplastic resin on only one surface of the mixed paper. The method of claim 1, A heat sealable wrapping paper, wherein a size agent or a water repellent agent is added to the mixed paper. The method according to any one of claims 1 to 3, The rice cake in the said mixed paper is 25-55 g / m <2>, The content rate of the pulp fiber in the said mixed paper is 50-75 weight%, The content ratio of the thermoplastic resin fiber in the said mixed paper is 50-25 weight%, The heat sealable wrapping paper characterized by the above-mentioned. 50 to 75% by weight of pulp fibers and 50 to 25% by weight of thermoplastic resin fibers are kneaded, and a sizing agent is added to use mixed paper having 25 to 55 g / m2 of rice flats, A heat seal package, characterized in that the sealing portion of the object is sealed with a heat seal while the article is wrapped. The method of claim 5, The thermoplastic resin fiber is a heat seal package, characterized in that the core (poly), sheath (core) is a composite fiber having a core-in-sheath structure of polypropylene having a lower melting point than the core. The method according to claim 5 or 6, A heat seal package, wherein the size agent is an alkyl ketene dimer.

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