JPS6311228B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a packaging tape used for packaging or bundling articles, and in particular, a packaging tape that exhibits pressure-sensitive adhesive properties only between both sides of the tape base material. , relates to a packaging tape on which a self-adhesive layer is formed that does not exhibit adhesiveness to other objects.

[Conventional technology]

When packing cardboard boxes, bundling long objects such as electric wires and optical fibers, various printed materials, documents, etc., it is common to bind them with strings or plastic bands. .

However, in order to wrap a string or band without loosening, tighten the string or band around the packaged item by applying tension to it, then tie both ends of the string and tie a knot. This necessitates complicated processing such as forming the band and fixing both ends of the band to each other using connecting fittings.

Further, in order to eliminate such complicated processing and reduce the labor of packaging work, duct tape is also used.

However, since adhesive tapes such as duct tape strongly adhere to the surface of the packaged object, it may not necessarily be a preferable packaging material depending on the type of the packaged object and the purpose of the packaging operation.

For example, if you use adhesive tape to bind bundles of documents, rolls of paper, etc. or to pack cardboard boxes, it will not only be very difficult to remove the adhesive tape later, but it will also damage the packaged items when you remove the tape. This has the disadvantage that letters, designs, etc. printed on the surface may be peeled off, and in some cases, the packaged item itself may be torn off. Another problem is that the adhesive remains attached to the surface of the object to be packaged after the adhesive tape is peeled off, and dust and the like adhere to the adhesive, resulting in significant staining of the surface of the object to be packaged.

In addition, there are weak adhesive tapes with adhesive layers that have lower adhesive strength than duct tape and ordinary cellophane adhesive tapes (Japanese Patent Application Laid-Open No. 1989-1999).
76632, Utility Model Publication No. 107653), this simply weakens the adhesion to the packaged object so that it can be peeled off without damaging the surface of the packaged object. Since the tape tries to compensate for the weak adhesive force by adhering both ends of the tape to each other using adhesive layers, it has the drawback that it cannot inherently provide strong binding force. . Therefore, packaging for cardboard boxes, electric wires, etc. that require strong binding force on the order of kilograms,
It cannot be used for binding documents, etc., and is only used for binding vegetables such as green onions and chives. Also,
Low-adhesive tapes have a weak adhesive force, so when packaging textile products, feather products, paper products, etc., there is a risk that the surface of the tape may be stained or damaged by the adhesive.

Furthermore, in the past, a binding tape has been proposed in which a non-adhesive self-adhesive layer is formed on one side of a tape base material and wound into a roll (Utility Model Application Publication No.
(See Publication No. 126977).

This tape is made by applying silicone rubber or butyl rubber, which has traditionally been used as a cold sealing material for sealing paper envelopes, to one side of the tape base material and drying it. The surfaces are self-adhesive.

However, similar to the case of cold sealing paper envelopes, this tape uses silicone rubber or butyl rubber applied directly to the surface of the tape base material and dries to form a self-adhesive layer. When the layers are peeled off from each other, each layer easily peels off from the surface of the tape base material, making it impossible to reuse it.

In other words, silicone rubber and butyl rubber have relatively good adhesion to the surface of hygroscopic paper, so they are used in cold seals, which are applied to the surface of paper envelopes to seal the openings. It is well known from experience that when a paper envelope is opened, the paper peels off in chunks, making it impossible to seal it completely again. Furthermore, cellophane and plastic films, which are not hygroscopic, cannot be firmly anchored even if a film of printing ink is formed on the surface, so when peeling off the self-adhesive layers that have adhered to each other, However, the silicone rubber or butyl rubber forming the self-adhesive layer forms a lump from the surface of the tape base material and easily peels off, resulting in a problem that it cannot be reused.

In addition, packaging tapes that have a self-adhesive layer formed on one side of the tape base material naturally have the tape on the side where both ends of the tape that are wrapped around the packaged item come into contact with the surface of the packaged item. Since the tape has to be adhered face to face, it easily comes undone due to the repulsive force of the packaged object trying to return to its original shape against the binding force of the tape. Furthermore, when the tape base material is made of a stretchable plastic film, there is a problem in that the tape, which is wrapped around the packaged item under tension, easily comes undone due to the contraction force.

[Problem that the invention seeks to solve]

For this reason, the present inventor has discovered that a tape that is wrapped around an object to be wrapped and self-fused between tape surfaces can easily unravel even when subjected to the repulsive force of the object to be packaged or the shrinkage force of the tape base material. Furthermore, research was conducted with the intention of realizing a packaging tape in which the self-adhesive layer does not peel off from the surface of the tape base material when the self-adhesive tape surfaces are peeled off and unwrapped.

As a result, by forming self-adhesive layers on both sides of the tape base material and wrapping it around the object, the ends of the tape base are self-fused so that the front and back surfaces overlap. In addition to being able to wrap with extremely strong binding force, the self-adhesive material that forms the self-adhesive layer is mixed with a water-soluble adhesive to firmly anchor the entire self-adhesive layer to the tape base material. It was concluded that peeling of the adhesive layer could also be prevented.

Based on this idea, we applied a mixture of rubber latex and water-soluble adhesive to both sides of the tape base material and dried it to form a self-adhesive layer that does not adhere to other objects, and then wrapped this into a roll for packaging. I got a tape for this purpose.

However, in some cases, the adhesive force between the self-adhesive layers of this packaging tape is so weak that the ends of the tape cannot be pressed together with sufficient strength for practical use, or conversely, the adhesive strength between the self-adhesive layers is too weak for practical use. A new problem occurred in that the adhesive force was too strong and the self-adhesive layer was peeled off from the surface of the tape base material.

As a result of further research, we found that the causes of such problems are, firstly, that the self-adhesive layer is formed on both sides of the tape base material and wound into a roll, and secondly, the self-adhesive force. A self-adhesive layer is created by a mixture of rubber latex, which provides self-adhesive force but also weakens the anchoring force to the tape substrate, and water-soluble adhesive, which provides anchoring force but also weakens the self-adhesive layer. It was found that this is due to the formation of

In other words, if the amount of water-soluble adhesive in the self-adhesive layer is too large, it will not exhibit any adhesive effect after it is applied to the surface of the tape base material and dries and hardens, resulting in poor adhesion due to the relative reduction of rubber latex and packaging. It becomes impossible to apply sufficient binding force to the tape. On the other hand, if the amount of rubber latex is too large, the anchoring ability to the tape substrate will decrease due to the relative decrease of the water-soluble adhesive that anchors the self-adhesive layer to the tape substrate, and the self-adhesive tape surfaces will become attached to each other. When the tape is peeled off, the self-adhesive layer peels off from the surface of the tape base material, making it impossible to reuse it, and blocking becomes noticeable between the self-adhesive layers that are fused to each other when wound up into a roll. Even when the tape is unrolled, the self-adhesive layer is easily peeled off from the surface of the tape base material, making the unrolled tape unusable. In addition, if the amount of rubber latex is extremely large, excessive tensile force due to blocking will be applied when unwinding the tape wound into a roll, causing the tape to break, or in severe cases, it may be impossible to unwind the tape. It becomes.

Therefore, the present invention eliminates poor adhesion between self-adhesive layers by adjusting the mixing ratio of rubber latex and water-soluble adhesive that form the self-adhesive layer within a certain range, and at the same time eliminates adhesion defects on both sides of the tape base material. The object of the present invention is to completely eliminate the problem of peeling of the self-adhesive layer from the tape base material due to blocking, which is an unavoidable problem for tapes wound into rolls by forming a self-adhesive layer on the tape.

[Means for solving problems]

In order to achieve this object, the packaging tape according to the present invention has a tape base material made of cellophane or plastic film, and an undercoat layer is formed on both sides of the tape base material, and at least one of the undercoat layers is applied to the tape base material. Rubber latex and a water-soluble adhesive are applied to both sides of the tape base material, which is formed of a printing ink film having a vehicle resin with good adhesion and an undercoat layer, to an adhesion within the range of 0.48 to 1.80. It is characterized in that a self-adhesive layer is formed by applying and drying an aqueous solution uniformly mixed at a weight ratio of agent/latex, and then wound into a roll.

[Effect]

Since the packaging tape according to the present invention has a self-adhesive layer formed on both sides of the tape base material, both ends of the tape wrapped around the object to be packaged can be self-adhesive so that the front and back sides overlap. Items to be packaged can be tightly bound. Therefore, the tape is prevented from unraveling due to the repulsive force of the packaged object or the contractile force of the tape base material when it is tied up.

In addition, the self-adhesive layers self-adhere to each other with a sufficiently practical adhesive strength on the order of kilograms, and at the same time, they are anchored to the tape base material with a force stronger than the self-adhesive strength, so they adhere to each other. The self-adhesive layers do not peel off from each other, and the tape does not peel off from the surface of the tape base material when the tape is unwound.

〔Example〕

Embodiments of the present invention will be specifically described below based on the drawings.

FIG. 1 is a perspective view showing an example of the packaging tape according to the present invention, and FIG. 2 is a cross-sectional view taken along the line -2.

In the figure, 1 is a tape base material made of plastic film such as cellophane, polyethylene, polyester, polypropylene, etc., 2 is an ink film formed by applying printing ink to the back side of the tape base material 1 and drying, and 3 is a tape. A transparent ink film is formed by applying and drying the printing ink without the colorant on the surface side of the base material 1, and 4 and 4 are rubber latex and water-soluble coatings on the ink films 2 and 3. This is a self-adhesive layer formed by applying and drying an aqueous solution containing a uniform mixture of adhesives at a predetermined adhesive/latex weight ratio.

Here, among the plastic films serving as the tape base material 1, polypropylene, polyethylene, etc., which do not have good adhesion to printing ink, should be used before applying the printing ink, considering the anchoring properties of the self-adhesive layers 4, 4, which will be described later. The adhesion of the printing ink to the tape base material 1 is improved in advance by subjecting it to a surface treatment using gas flame, corona discharge, etc., or by coating the surface with polyvinylidene chloride resin or the like.

Note that the polypropylene used as the tape base material 1 includes biaxially oriented polypropylene (OPP).
and unoriented polypropylene (CPP).

In addition, the composition of the printing ink applied to the tape base material 1 generally includes a colorant, which is a coloring component, and a component that spreads the colorant onto the surface of the tape base material 1 to form ink films 2 and 3. a vehicle
and an auxiliary agent consisting of a dispersant, an antifoaming agent, a plasticizer, etc. However, in the present invention, the tape base material 1, which is the printing medium, takes into consideration the anchoring properties of the self-adhesive layers 4 and 4. It is necessary to select a vehicle that has particularly good adhesion to the tape base material 1, depending on the material of the tape base material 1.

For example, the vehicle for gravure ink consists of a resin and a solvent, and examples of vehicle resins that have good adhesion to the tape base material 1 and have a high ability to form an ink film include nitrocellulose (nitrified cotton),
Examples include ethyl cellulose, polyamide resin, vinyl chloride/vinyl acetate copolymer resin, polyvinyl butyral, acrylic resin, polyurethane resin, and polyester resin. Among printing inks that have good adhesion to the tape substrate 1, two-component reactive printing inks that use a resin having a reactive group as a vehicle are one of the two components used to form an ink, and the other as a curing agent. The ink film obtained in this way is extremely tough and has excellent durability, so it is very suitable as a printing ink for use in the present invention. Note that such two-component reactive printing inks include polyurethane resin-based gravure inks and screen inks using resins such as epoxy and melanin as vehicles.

The tape T of the present invention shown in FIGS. 1 and 2 is produced by applying printing ink containing the vehicle resin as described above to both sides of a tape base material 1 and drying it to form ink films 2 and 3. 2
and 3 as an undercoat layer, and an aqueous solution of rubber latex and a water-soluble adhesive uniformly mixed at an adhesive/latex weight ratio in the range of 0.48 to 1.80 is coated and dried, so that the thickness thereof is, for example, 0.005 to 1.80.
Self-adhesive layers 4, 4 of 0.02 mm are formed.

This self-adhesive layer 4 exhibits pressure-sensitive adhesion only between itself, and has the property of not adhering to other objects such as items to be packaged.

Here, the rubber latex, which is the first main component forming the self-adhesive layer 4, is a self-adhesive material that allows the self-adhesive layers 4, 4 to self-adhere to each other by the fusing force of the rubber exhibited in its dry state. It is an ingredient for imparting sex.

On the other hand, the water-soluble adhesive, which is the second main component, is used to adhesively bond the self-adhesive layer 4 to the ink films 2 and 3 formed on the surface of the tape base material 1 to give it anchoring properties. At the same time, it dries and solidifies in the self-adhesive layer 4 to form a part that does not contribute to the adhesiveness of the self-adhesive layer 4, thereby reducing the self-adhesive force caused by the rubber latex component. do.

By selecting the amount of the rubber latex and water-soluble adhesive to be used within the range of 1:0.48 to 1.80 expressed as a weight ratio of the water-soluble adhesive to the rubber latex, the self-adhesive layer 4 is able to resist other objects. does not adhere and has sufficient self-adhesive force between the self-adhesive layers 4, 4, and has an anchoring force that prevents the self-adhesive layer 4 from peeling off from the surface of the tape base material 1 due to the self-adhesive force. It will become.

Note that when this weight ratio is less than 0.48, the rubber latex component becomes excessive and the water-soluble adhesive component decreases relatively, so the fusion properties of the rubber latex become extremely strong and the self-adhesive layers 4 weigh more than 6 kg. On the other hand, the adhesiveness of the self-adhesive layer 4 to the ink coatings 2 and 3 of the tape base material 1 decreases, and the anchoring force becomes weaker than the self-adhesive force, and the adhesiveness of the self-adhesive layer 4 to the ink coatings 2 and 3 of the tape base material 1 decreases, and the anchoring force becomes weaker than the self-adhesive force. Self-adhesive layer 4, 4
When peeling them off, the self-adhesive layer 4 peels off from the surface of the tape base material 1.

Furthermore, when the weight ratio exceeds 1.80, the water-soluble adhesive component that does not contribute to adhesiveness becomes excessive and the rubber latex component decreases relatively, so the anchoring force of the self-adhesive layer 4 to the tape base material 1 is strong. However, the adhesive force between the self-adhesive layers 4,4 decreases to 1 kg or less, making it impossible to obtain a practically sufficient adhesive strength.

Here, the rubber latex is not limited to natural rubber latex, but includes styrene-butadiene rubber, nitrile rubber, polychloroprene rubber,
Latexes of synthetic rubber such as polyisoprene rubber can also be used.

Further, as the water-soluble adhesive, an ordinary adhesive that exhibits good anchoring properties for the ink coatings 2 and 3 of the tape base material 1, such as an acrylate-based and vinyl acetate-based water-based emulsion adhesive, may be used. Can be done.

Self-adhesive layers 4, 4 formed in this way
It was confirmed through experiments that the adhesive directly anchored to the ink coatings 2 and 3 of the tape base material 1, and exhibited stronger adhesion than the adhesive layer in ordinary printed adhesive tapes.

Therefore, in the case of the tape T of the present invention, a primary coat is separately applied between the adhesive layer and the ink film as in the conventional printed adhesive tape, and the adhesive layer and the ink film are firmly bonded to each other through the primary coat. There is no need to worry about anchoring.

That is, in the tape T of the present invention, the ink films 2 and 3 alone sufficiently fulfill the role of the undercoat layer in a normal adhesive tape, and therefore the self-adhesive layers 4 and 4 serve as the undercoat layer. Ink film 2
and 3, it is firmly adhered to the tape base material 1 and has strong anchoring properties.

The above is an example of the configuration of the packaging tape according to the present invention, and its operation will be explained next.

FIG. 3 is a perspective view showing an example of the use of the packaging tape T according to the present invention, and in the figure, 5 is a cardboard box to be packaged.

In the case of ordinary adhesive tapes, packaging or sealing effects can be obtained by adhering the adhesive layer formed on one side to the surface of the cardboard box 5, but with the packaging tape T according to the present invention, the packaging or sealing effect can be obtained. A tape base material 1 with self-adhesive layers 4, 4 formed on both sides is wound around a cardboard box 5, and the self-adhesive layers 4, 4 are formed on the front and back surfaces of the tape base material 1.
4 are pressed with their overlapping portions 6 to form a pressure-sensitive adhesive bond to each other, thereby providing a binding force for packaging.

Here, since the overlap portion 6 of the self-adhesive layers 4 and 4 has adhesive strength on the order of kilograms (approximately 1Kg to 6Kg) against tension in the horizontal direction, a solid packaging state is reliably maintained. As with the use of adhesive tape such as duct tape, no loosening occurs over a long period of time.

Next, when unwrapping, the end of the tape T is pulled and peeled off in the opposite direction to the winding direction, but at this time, the self-adhesive layers 4, 4, which are pressure-sensitively bonded to each other, are shows almost no resistance (resistance:
(approximately 100 g to 400 g), and since the self-adhesive layer 4 in contact with the surface of the cardboard box 5 does not adhere to the surface of the cardboard box 5 at all, unlike adhesive tape, it can be easily and easily removed from the surface of the cardboard box 5. It can be removed smoothly and does not stain or stain the surface.
Will not be damaged.

In this way, the packaging tape T has features not found in conventional adhesive tapes, and since the ink film 2 is printed with various patterns, colors, characters, etc., it is a new type that has never existed before. It is very useful as a color tape, and in addition to the above, it can be widely applied to, for example, bundles of documents such as slips, temporary binding of textile products, packaging of calendars and drafting paper, etc.

Hereinafter, preferred embodiments of the present invention will be described in more detail.

First, a non-stretchable biaxially oriented polypropylene film (OPP) is used as the tape base material 1, and before forming a coating of printing ink, both sides of the tape base material 1 are subjected to corona discharge treatment or plasma treatment. The surface of the tape base material 1 is made easily adhesive.

Then, a two-component reactive gravure ink using a polyurethane resin as a vehicle is prepared as a printing ink to be applied to the tape base material 1.

This polyurethane resin-based gravure ink is made from vinyl chloride/vinyl acetate copolymer resin that has functional groups such as hydroxyl groups, polyester polyol, polyether polyol, etc.
Isocyanate prepolymer (curing agent) during printing
This is an ink that is reacted and cured by adding
Immediately before use, the two liquids are mixed and printed, and after printing, a reaction occurs following evaporation of the solvent such as alcohol, resulting in curing.

Here, the gravure ink containing a desired colorant such as a pigment or dye is applied to the back side of the tape base material 1.
Further, on the surface side of the tape base material 1, an ink consisting only of a vehicle and an auxiliary agent without the colorant from the gravure ink is printed using a gravure printing machine, and then applied and dried. As a result, an ink film 2 exhibiting a predetermined pattern, color, etc., and a transparent ink film 3 are formed on both sides of the tape base material 1, respectively.

Then, the tape base material 1 on which the ink films 2 and 3 have been applied and formed in this way is placed in a drying oven and heated and dried at a temperature of about 40° C. for about 24 hours to further accelerate the reaction. By doing so, tough ink films 2 and 3 that adhere extremely strongly to the surface of the tape base material 1 can be obtained.

Next, a 41.3% aqueous emulsion (solid content concentration 46%) of a copolymer resin mainly composed of methyl methacrylate and butyl acrylate as a water-soluble adhesive component was added to 20.7% water and 1.7% ammonia aqueous solution with a 28% concentration. % and natural rubber latex as a rubber latex component to this mixed liquid.
33.1% (solid content concentration approximately 60%) and a wetting agent mainly composed of sulfosuccinate ester 3.3% (solid content concentration approximately 44%) are further mixed to prepare an aqueous solution for forming the self-adhesive layer 4 ( Adhesive/latex weight ratio: approx. 0.95/1).

Then, the aqueous solution prepared in this manner is applied to the tape base material 1 on which the ink films 2 and 3 are formed on both sides.
The self-adhesive layers 4, 4 having a thickness of about 0.006 mm are formed by uniformly coating and drying the adhesive on both sides while being transported at a required speed.

Next, after coating the surfaces of the self-adhesive layers 4, 4 with 99.8% pure silica fine particles or cornstarch made of corn starch with a particle size of about 10 to 25 microns as an anti-blocking agent, this is rolled into a paper tube 7. Wind it up.

The tape wound around the paper tube 7 in this manner is cut along with the paper tube 7 to a required width, and a packaging tape T having a width of 18 mm is completed.

The two samples unrolled and cut from this tape T are stacked one on top of the other, and the self-adhesive layers 4 of each are pressure-sensitive adhesive bonded to each other (longitudinal overlap amount is 10 mm), and the free end of one sample is fixed. At the same time, tension was applied along the tape longitudinal direction from the free end side of the other sample. The average adhesive strength between the self-adhesive layers 4 and 4 in this horizontal peel test was approximately
It weighed 6.0Kg.

Next, when a peeling tension perpendicular to the tape surface was applied to one adhesive end of the overlapped portion of the samples that were bonded together in the same way, the average resistance was approximately 240 g. .

As mentioned above, the packaging tape T shown in this example is
The tape base material 1 is made of a water-resistant polypropylene film, and an ink film 2 on which a desired print is applied is formed on both sides, and it exhibits pressure-sensitive adhesiveness only between itself and other objects. Since the self-adhesive layers 4, 4 which do not adhere to each other are formed, it is extremely suitable for use as a packing tape for cardboard boxes or a tape for binding vegetables, for example, on which the manufacturer's information is printed.

In particular, the self-adhesive layers 4, 4 formed on both sides of the tape base material 1 do not adhere or adhere to the surface of the cardboard box 5 to be packed or the vegetables to be tied, so when the tape T is removed, the cardboard Not only does it not damage the box 5 or the vegetables, it also has the excellent property of self-adhesive even when water droplets etc. adhere to the surface and it becomes wet. Unlike weakly adhesive tapes that do not adhere to vegetables by reducing the adhesive strength of the adhesive layer, the tape T exhibits extremely strong adhesive strength on the order of kilograms at the overlap part 6, so it is extremely effective. It has a strong binding force, and the adhesion between the self-adhesive layers 4, 4 will not peel off due to the contractile force of the tape T or the repulsive force of the cardboard box 5, etc., which is applied during packaging or bundling.

Further, the adhesive strength between the self-adhesive layers 4, 4 is very strong at about 6 kg in the horizontal direction, but the adhesive strength between the self-adhesive layers 4, 4 and the ink films 2 and 3, and the ink film Since the adhesive force between 2 and 3 and the tape base material 1 is stronger than that, the self-adhesive layer 4,
The anchoring property of No. 4 to the tape base material 1 is extremely strong.

As a result, when unwinding the packaging tape T wound around the paper tube 7, or when peeling off the overlap part 6 of the packaging tape T used for packaging the cardboard box 5, etc., the self-adhesive layers 4, 4 can be Due to the adhesive force of the self-adhesive layers 4, 4 themselves are attached to the ink films 2 and 3.
It does not peel off from the tape substrate 1 or together with the ink coatings 2 and 3.

Therefore, the packaging tape T according to the present invention is
Not only does it have a strong binding force, but unlike conventional non-adhesive self-adhesive tapes that simply coat one side of the tape base with silicone rubber or butyl rubber used as a cold sealing material, it can be reused over and over again. It has the particular advantage of being usable.

Further, depending on the self-adhesive layers 4, 4, the ink films 2 and 3 serve as an undercoat layer for the tape base material 1 as they are, so the self-adhesive layer 4
There is no need to apply a separate primary coat between the ink films 2 and 3, and there is an advantage that manufacturing is simple.

In addition, in the above-mentioned embodiment, the tape base material 1
The case where gravure ink containing a desired coloring agent is applied to one side of the sheet and transparent gravure ink containing no coloring agent is applied to the other side is explained.
The present invention is not limited to this, and printing ink such as gravure ink having a desired coloring material may be applied to both sides of the tape base material 1 to differentiate the colors.

In addition, an undercoat layer consisting of an ink film 2 or 3 is formed by coating and drying printing ink only on one side of the tape base material 1, and a normal undercoat layer in addition to the ink film is formed on the other side. It's okay if it's hot.

Furthermore, when using a so-called moisture-proof cellophane tape (manufactured by Tokyo Cellophane Co., Ltd.: MST#400) with a moisture-proof layer formed on the surface as the tape base material 1, printing ink is applied only to one side and dried to form an ink film. 2 or 3, and the self-adhesive layer 4 is formed thereon, and the self-adhesive layer 4 may be formed directly on the moisture-proof layer on the other side. This is because the moisture-proof layer serves as an undercoat layer for the self-adhesive layer 4 and can provide sufficient anchoring properties to the tape base material 1.

[Effects of the Invention] As described above, the packaging tape according to the present invention can be applied to the surroundings of the packaged items when packaging or bundling them, similar to conventionally used adhesive tapes such as duct tape. With the simple operation of just hanging it around, you can obtain a secure packaging with strong binding force, and
When unwrapping this packaging, you can remove it quickly and easily just by peeling off the overlapping part of the tape where the self-adhesive layers adhere to each other, just like untying a string, so you can avoid staining the surface of the packaged item. Will not be damaged.

Moreover, the self-adhesive layers self-adhere to each other with a strong adhesive force on the order of kilograms, and at the same time are anchored to the tape base material with a force stronger than that adhesive force, so that the overlapping portion of the tape used for packaging can be An excellent effect is that the self-adhesive layer does not peel off from the surface of the tape base material when it is peeled off, and it can be reused many times.

In addition, when unwinding a roll of tape, the self-adhesive layer may peel off from the tape base material, making it unusable, or excessive tensile force may be applied to the unrolled tape, causing the tape to break. It has a very good effect of reliably eliminating the adverse effects such as those that occur.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the packaging tape according to the present invention, FIG. 2 is a cross-sectional view taken along the - line, and FIG. 3 is a perspective view showing an example of the use of the packaging tape according to the present invention. Explanation of symbols, T...Packaging tape, 1...Tape base material, 2, 3...Ink film, 4...Self-adhesive layer, 5...Cardboard box, 6...Overlap portion, 7...Paper tube .

Claims (1)

[Scope of Claims] 1. An undercoat layer is formed on both sides of a tape base made of cellophane or plastic film, and at least one of the undercoat layers contains a vehicle resin having good adhesiveness to the tape base material. A rubber latex and a water-soluble adhesive are uniformly mixed on both sides of the tape substrate, which is formed with a coating of printing ink and has an undercoat layer, respectively, at an adhesive/latex weight ratio within a range of 0.48 to 1.80. A packaging tape characterized in that a self-adhesive layer is formed by coating and drying an aqueous solution, and the tape is wound up into a roll. 2. The packaging tape according to claim 1, wherein a film of the printing ink is formed on both sides of the tape base material, and the printing ink forming one of the films is a printing ink that does not contain a colorant. . 3. The packaging tape according to claim 1, wherein the printing ink is a two-component reactive gravure ink based on polyurethane resin.