JP2535686B2 - Adhesive tape - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive tape used as, for example, a fastener tape for fixing a front part and a back part of a disposable diaper.

[0002]

2. Description of the Related Art As a fastener tape for fixing a front part and a rear part of a paper diaper, Japanese Utility Model Laid-Open No. 59-153304 discloses a strip-shaped tape base material at a position displaced from an intermediate portion along the longitudinal direction. By folding back the two tape-like materials, the tape base materials are partially overlapped with each other to form pressure-sensitive adhesive layers made of pressure-sensitive adhesives having different compositions on the two surfaces overlapping each other. There is described a configuration in which another adhesive layer is formed on a surface of one surface which is exposed without overlapping and on the surface on which the adhesive layer is formed.

That is, according to this prior art, three adhesive layers are provided in series on one surface of a tape base material, and two adjacent adhesive layers are overlapped with each other to expose only one adhesive layer. This exposed adhesive layer,
Two adhesive layers that are pasted on the outer surface of either the front part or the back part of the disposable diaper (generally the posterior part) and turned over the tape base material to overlap when using the disposable diaper. Is exposed, and the other part (generally the front part) of the front part and the back part of the disposable diaper is attached.

[0004]

This prior art focuses on the property that the adhesive layers having different compositions can be peeled from each other by laminating them. With the configuration of this prior art, the adhesive layer is used before using a disposable diaper. Since there is no need for a release tape to protect the release tape, it is possible to prevent an infant from swallowing the release tape and to simplify the structure.

However, in this prior art, three adhesive layers are arranged in series only on one surface of the tape substrate, and therefore the tape substrates are folded back so as to partially overlap each other,
An adhesive layer for pre-fixing the paper diaper must be formed only on the exposed portions without overlapping, which causes a problem that the length of the tape base material becomes long and the cost increases. It was This problem becomes more prominent as the adhesive strength to the diaper is increased.

Further, as described above, when the paper diaper is used, since the pressure-sensitive adhesive layers overlapping each other are peeled off and the tape base material is turned over into a single plate, it can be easily peeled off by applying a certain amount of force. Although it is necessary to maintain the state where the pressure-sensitive adhesive layers are adhered with an appropriate strength, the conventional type uses the phenomenon that the pressure-sensitive adhesive layers that have been overlapped are integrated with each other over time. At that time, there was a problem that it was difficult to peel it off.

The present invention aims to solve these problems.

[0008]

In order to achieve this object, the present invention provides that "one tape base material is folded back so as to overlap each other on one side thereof, and the tape base materials are overlapped with each other. The first adhesive layer is provided on one of the two surfaces with the fold in between, and the auxiliary adhesive layer is provided on the other surface with the fold in between, and the first adhesive layer and the auxiliary adhesive layer are combined. By changing the composition,
A pressure-sensitive adhesive tape comprising the first pressure-sensitive adhesive layer and an auxiliary pressure-sensitive adhesive layer releasably adhered, wherein the first pressure-sensitive adhesive layer is formed of a pressure-sensitive adhesive containing no silicone-based polymer. , The auxiliary adhesive layer, the adhesive polymer 100
It is formed from a pressure-sensitive adhesive having a composition in which 0.2 to 30 parts by weight of a silicone-based polymer is blended with respect to parts by weight, and further, an auxiliary pressure-sensitive adhesive layer is provided on the other part of the tape base material with the fold line sandwiched therebetween. The second pressure-sensitive adhesive layer is provided on the surface opposite to the front surface and the rear surface. "

[0009]

In this configuration, when the rear part of the disposable diaper is used as a fastener tape for fixing the rear part to the front part of the front part, the second adhesive layer is attached to the inner surface of the rear part. The adhesive tape is attached in advance to the paper diaper by attaching, and when the paper diaper is used, the first pressure-sensitive adhesive layer and the auxiliary pressure-sensitive adhesive layer are peeled off, and the tape base material is turned over into a plate shape, and then exposed. The first pressure-sensitive adhesive layer and the auxiliary pressure-sensitive adhesive layer may be pressed against the front surface of the front part of the paper diaper to be attached.

In this case, the second pressure-sensitive adhesive layer for fixing the pressure-sensitive adhesive tape to a paper diaper or the like in advance is provided on the surface of the tape substrate opposite to the auxiliary pressure-sensitive adhesive layer.
In other words, since the second pressure-sensitive adhesive layer can be formed in a large area in a state of overlapping with the auxiliary pressure-sensitive adhesive layer, the tape base material does not necessarily have to be folded back so as to partially overlap with each other, and the tape base material does not have to be completely folded back. It can also be formed in an overlapping state.

Therefore, according to the present invention, there is an effect that the length of the tape base material can be shortened without impairing the bonding strength and the cost can be reduced. Further, the easiness of turning over the tape base material into a single plate at the time of use has been solved by using the above composition for the first pressure-sensitive adhesive layer and the auxiliary pressure-sensitive adhesive layer. That is, when the composition of the present invention is used for the first pressure-sensitive adhesive layer and the auxiliary pressure-sensitive adhesive layer, it is presumed that the silicone contained in the auxiliary pressure-sensitive adhesive layer bleeds to the pressure-sensitive adhesive layer surface over time. The adhesive strength of the first pressure-sensitive adhesive layer did not increase with the passage of time, and the first pressure-sensitive adhesive layer and the auxiliary pressure-sensitive adhesive layer did not gradually become difficult to peel off with the passage of time.

In this case, the adhesive strength of the auxiliary pressure-sensitive adhesive layer is lowered by blending the silicone polymer,
Since the auxiliary pressure-sensitive adhesive layer is located between the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer, when used for an article such as a paper diaper,
The peeling of the auxiliary pressure-sensitive adhesive layer does not cause the first pressure-sensitive adhesive layer to be peeled off. Therefore, the adhesive strength of the pressure-sensitive adhesive tape (part and The strength for fixing parts) does not decrease.

Therefore, according to the present invention, there is also an effect that the usability of the pressure-sensitive adhesive tape can be improved without impairing the fixing strength to the parts such as paper diapers.

[0014]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a perspective view of a wound body 2 of an adhesive tape 1, and FIG. 2 is a sectional view taken along line II-II of FIG. 1. A wound body 2 obtained by winding a long tape material in a roll shape is linear. Then, the adhesive tape 1 is obtained as a single body by feeding it out and cutting the adhesive tape into pieces each having a predetermined size.

The adhesive tape 1 has a tape base material 3 formed in a rectangular shape from a synthetic resin film such as polypropylene film or a sheet material such as paper or cloth,
The tape base material 3 is folded back in two sheets with the middle part along the longitudinal direction as the center so that one side thereof is exactly overlapped, and the one side with the fold line sandwiched between the two overlapping side surfaces 3a and 3b. Is provided with the first adhesive layer 4, and the auxiliary adhesive layer 5 is provided on the other surface 3b sandwiching the fold line.

At this time, for example, the first adhesive layer 4 is replaced with S
The IS block copolymer is formed with a pressure-sensitive adhesive formed by mixing 50 parts by weight of a petroleum-based resin with 50 parts by weight of the IS block copolymer, and the auxiliary pressure-sensitive adhesive layer 5 is added to 98 parts by weight of an acrylic-based pressure-sensitive adhesive. As described above, the first pressure-sensitive adhesive layer 4 is formed of a silicone-free pressure-sensitive adhesive and the auxiliary pressure-sensitive adhesive layer 5 is formed of a silicone-containing pressure-sensitive adhesive. To do. Then, the first pressure-sensitive adhesive layer 4 and the auxiliary pressure-sensitive adhesive layer 5 have different compositions from each other.
It is affixed in a state in which it can be peeled off as indicated by the alternate long and short dash line.

Of the parts on both sides of the tape base material 3 that sandwich the fold, on the outer surface of the part where the auxiliary pressure sensitive adhesive layer 5 is formed, that is, on the front and back sides of the tape base material 3 opposite to the auxiliary pressure sensitive adhesive layer 5. The first adhesive layer 4 is formed on the surface located on the side.
The second pressure-sensitive adhesive layer 6 formed of the pressure-sensitive adhesive having the same composition as the above is provided so as to extend over substantially the same range as the auxiliary pressure-sensitive adhesive layer 5. A release layer 7 for the second pressure-sensitive adhesive layer 6 is provided on the outer surface of the tape base material 3 near the one end so that the tape base material 3 can be peeled off and rolled out from the wound body 2.

Further, at one end of the tape base material 3, a knob portion 3c to which the first pressure-sensitive adhesive layer 4 is not applied is formed to serve as a clue for peeling during use. FIG. 3 is a perspective view of a disposable paper diaper using the adhesive tape as a fastener tape, and FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3, in which the second adhesive layer 6 is a tip portion of a rear part A1 of the paper diaper A. By sticking to the inner surface, the pressure-sensitive adhesive tape 1 is fixed to the paper diaper in advance, and at the time of use, the first pressure-sensitive adhesive layer 4 and the auxiliary pressure-sensitive adhesive layer 5 are peeled off to form the tape base material 3 into a plate shape. Turn over and put the first adhesive layer 4 and the auxiliary adhesive layer 5 together.
The tape is attached to the center tape A3 provided on the front surface of the front part A2. As a result, the posterior part A1 of the paper diaper A is changed to the anterior part A2.
Fixed to.

The second pressure-sensitive adhesive layer 6 is provided on the tape base material 3 in a state of being located on the opposite side of the auxiliary pressure-sensitive adhesive layer 5, so in other words, the second pressure-sensitive adhesive layer 5 and the second pressure-sensitive adhesive layer are adhered to each other. Since the agent layer 6 can be overlapped with the agent layer 6, the length of the tape substrate 3 can be shortened to reduce the cost. The present inventor compared the shear adhesive strength between the product of the present invention and the conventional product by the following method.

That is, in the sample of the product of the present application, the tape base material 3 is formed with an unstretched polypropylene film having a thickness of 100 μm so as to have a width of 25 mm and a length of 40 mm, and the first adhesive layer 4 has a styrene content of 14 An adhesive comprising 50 parts by weight of a petroleum-based resin with respect to 50 parts by weight of a styrene-isoprene-styrene block copolymer of 50% by weight,
50 μm in thickness, length 1 along the longitudinal direction of the tape substrate 3
On the other hand, the auxiliary pressure-sensitive adhesive layer 5 is formed to 0 mm, and the addition-type silicone such as dimethylpolysiloxane containing 10% by weight of three-dimensional organopolysiloxane is added to 2 parts by weight of the auxiliary pressure-sensitive adhesive layer 5 to 98 parts by weight of the acrylic pressure-sensitive adhesive such as polybutyl acrylate. 50 μm in thickness, tape base material 3
A length of 20 mm was formed along the longitudinal direction.

On the other hand, the comparative sample was not provided with the auxiliary pressure-sensitive adhesive layer 5 of the present application, and the other constitution was the same as that of the product of the present application. Then, in a standard atmosphere of 23 ° C. and a humidity of 65%, these samples are formed by applying a release agent having a long-chain alkyl group on the surface of a stretched polypropylene film having a thickness of 25 μm to a thickness of 0.1 mm. The first pressure-sensitive adhesive layer 4 is superposed on the adherend so that the first pressure-sensitive adhesive layer 4 faces downward, and this is pressure-bonded by reciprocating a 2 Kg roller once at a speed of 50 mm / sec, and after leaving it for 30 seconds. , Tape base material 3 in one direction along its longitudinal direction by 300 m
The maximum load when the adhesive tape 1 was peeled from the adherend by pulling at a speed of m / min was read.

As a result, the maximum load required for peeling of the product of the present invention was 6.0 kg on average, whereas that of the conventional product was 3.9 kg on average, and the fixing strength of the product of the present invention was high. It was proven. Further, when a silicone-containing pressure-sensitive adhesive is used as the auxiliary pressure-sensitive adhesive layer 5, it is presumed that the silicone contained in the pressure-sensitive adhesive bleeds to the pressure-sensitive adhesive layer surface over time. The adhesive strength did not increase with time, and the peelability between the first pressure-sensitive adhesive layer 4 and the auxiliary pressure-sensitive adhesive layer 5 did not decrease with time. In this case, according to the experiments conducted by the inventor of the present application, it is preferable to add 0.2 to 30 parts by weight of a silicone-based polymer to 100 parts by weight of an acrylic or rubber-based pressure-sensitive adhesive polymer. When it is less than the range, it becomes difficult to peel off from the first pressure-sensitive adhesive layer 4, and when the compounding amount of the silicone-based polymer is more than this range, the adhesive strength is remarkably lowered.

5 to 7 show another embodiment of the present invention.
FIG. 5 shows that the tape base material 3 is folded back at a portion that is biased toward the end from the middle point between the left and right sides of the tape base material 3.
Are partially overlapped with each other, the first adhesive layer 4 is provided on one surface 3a of the two surfaces overlapping with each other, and the auxiliary adhesive layer 5 is provided on the other surface 3b. Auxiliary pressure-sensitive adhesive layer 5 on both the front and back sides of part 3d
The second adhesive layer 6 is provided on the surface opposite to the surface. Reference numeral 3e is a coloring portion for making the knob portion visible.

In the embodiment of FIG. 5, the first adhesive layer 4 and the second adhesive layer 4
This is effective when the adhesive layer 6 and the adhesive layer 6 are separated from each other. Further, when a stronger bonding strength is desired, the second pressure-sensitive adhesive layer 6 may be extended to the vicinity of the folded back central portion of the tape base material 3, as indicated by the alternate long and short dash line. In the embodiment of FIG. 6, both of the one end portion and the other end portion of the tape base material 3 are folded back so as to face each other toward the central portion of the tape base material 3, and both inner surfaces in the left and right overlapping portions. 3a and 3b,
While providing the first pressure-sensitive adhesive layer 4 and the auxiliary pressure-sensitive adhesive layer 5, respectively, the outer surface of the tape base material 3 at both overlapping portions
The second pressure-sensitive adhesive layer 6 is provided on the outer surfaces 3f, 3f located near the center of the. In this case, both the second pressure-sensitive adhesive layers 6 and 6 may be continuous as shown by the chain line.

As shown in FIG. 7, the pressure-sensitive adhesive tape 1 shown in FIG. 6 is attached to one member C via the second pressure-sensitive adhesive layer 6 to form the first pressure-sensitive adhesive layer 4 in both the left and right polymerized portions. It is used by peeling off the auxiliary pressure-sensitive adhesive layer 5, turning over the tape substrate 3 into a plate, and sticking the pair of left and right first and auxiliary pressure-sensitive adhesive layers 4 and 5 to the other member D. For example, it is suitable as a tape for fixing sanitary napkins.

6 to 7, the second pressure-sensitive adhesive layer 6 can be formed with the tape base material 3 overlapping the auxiliary pressure-sensitive adhesive layer 5, so that the entire length of the second pressure-sensitive adhesive layer 6 should be increased. It is possible to obtain a high fixing strength.

[Brief description of drawings]

FIG. 1 is a perspective view of an adhesive tape and a wound body thereof.

FIG. 2 is an enlarged sectional view taken along line II-II of FIG.

FIG. 3 is a perspective view of a disposable diaper using the adhesive tape according to the present invention.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a diagram showing another embodiment.

FIG. 6 is a sectional view showing still another embodiment.

FIG. 7 is a view showing a usage state of the adhesive tape of FIG.

[Explanation of symbols]

 1 Adhesive Tape 2 Roll of Adhesive Tape 3 Tape Base Material 4 First Adhesive Layer 5 Auxiliary Adhesive Layer 6 Second Adhesive Layer A Paper Diaper

Claims (1)

(57) [Claims] 1. A tape base material is loaded on one side thereof with a weight.
Fold it back into two pieces so that they overlap each other
One of the two sides that overlap each other with the crease in between
The first adhesive layer on one side, and the other side with the crease in between
Are provided with auxiliary pressure sensitive adhesive layers respectively, and these first pressure sensitive adhesive layer and
By changing the composition with the auxiliary adhesive layer,
The first adhesive layer and the auxiliary adhesive layer are detachably attached
A pressure-sensitive adhesive tape comprising:
Not formed with the adhesive, while the auxiliary adhesive layer
Based on 100 parts by weight of the adhesive polymer
A pressure sensitive adhesive with a composition of 0.2 to 30 parts by weight of a polymer.
And then fold the tape base material.
The other side and the side opposite to the surface on which the auxiliary adhesive layer is provided
An adhesive tape having a second adhesive layer on the surface of the adhesive tape.