JPH0588755B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an elastic fastening tape,
In particular, disposable diapers, sanitary products, clothing products,
The present invention relates to a fastening tape that has elasticity and is useful when fastening to parts of the body that are in direct or indirect contact with movement, such as athletic equipment. [Prior art] Conventional adhesive tapes are made of paper, film, nonwoven fabric,
Generally, the tape base material is a single material or a composite material such as cloth, and an adhesive is applied to the tape base material, and these tapes do not have elasticity. In addition, as a tape having elasticity, for example, in Japanese Patent Application Laid-open No. 51-68345 and Japanese Utility Model Application No. 57-157209, there is a tape for disposable diapers in which an elastic ring or band-like elastic body is arranged in the center of the tape. Proposed. [Problems to be Solved by the Invention] However, the above-mentioned conventional general tape base material is not suitable for applications that require a function of following movement in the vicinity of the fastening portion, such as disposable diapers. Furthermore, all of the proposals described in the above-mentioned publications have drawbacks such as a decrease in adhesive strength during use, breakage of the tape, and a decrease in productivity during processing, and are not practically satisfactory structures. That is, in the fastening tape described in JP-A-51-68345, since the elastic body at the center of the tape has a ring shape, when it is fastened to the surface of an adherend during use, it is difficult to attach the tape to the adjacent non-elastic body. When the elastic ring is stretched by grasping the end of the tape, a dogleg-shaped deformation occurs due to stress concentration in the boundary area between the elastic ring and the inelastic body, causing the inelastic body to reach the surface of the adherend. Significantly reduces the adhesion area of the adhesion surface and reduces adhesion. In addition, during use, the stress associated with the deformation of the elastic ring that follows the movement of the waist often acts in a direction other than the direction in which the tape is pulled, and at this time, the stress of the inelastic body that fixes the elastic ring acts in many cases. Since stress is concentrated in a point state on the front and back sides of the elastic ring side end, the inelastic body at the end is likely to break. On the other hand, Japanese Utility Model Application Publication No. 57-157209 proposes a tape structure in which an inelastic body is bonded to the back surface of both ends of a band-shaped elastic body. However, with such a structure, the bonded portion of the elastic body and inelastic body curls during processing of the tape, significantly reducing productivity, and when used as a fastening tape, the fastening surface If you do not apply pressure all over the entire surface, you will not be able to secure a sufficient adhesive area and thus adhesive force, and the tape will tend to peel off from the adherend due to the force of the tape trying to restore the curl even after adhesion. It has the following drawback. Moreover, the material having rubber elasticity useful as the above-mentioned elastic body has a tear strength that is weaker than a tensile strength.
That is, if minute scratches are formed at the end of the band-shaped rubber elastic material that constitutes the elastic part of the elastic fastening tape, the scratches propagate and expand due to repeated expansion and contraction during use, and eventually break and become unusable. It is often impossible. However, it is difficult to completely eliminate the occurrence of such minute scratches at the end of the tape when speeding up the assembly process of the tape. Therefore, an object of the present invention is to solve the above-mentioned problems, and to improve the fit to the body when worn, without the disadvantages such as a decrease in adhesion force during use, breakage of the tape, and decrease in productivity during processing. An object of the present invention is to provide a fastening tape having elasticity and excellent wearing comfort. [Means for Solving the Problems] As a result of various studies in order to solve the above-mentioned problems, the present inventors have developed a tape base in which the center portion is made of a stretchable elastic material and both ends are made of an inelastic material. Such a problem arises when cuts are provided in the elastic body in the elastic body in a stretchable adhesive tape in which an adhesive layer is provided on the same side of at least the two non-elastic bodies. We found that it is possible to solve the problem. That is, when the fastening tape 11 as shown in FIG. 9 with no breaks as described above is stretched, the fastening tape 11 as shown in FIGS.
As shown in FIG. 13, the deformation (necking) of the elastic body 1 in the center is large and propagates to the joint between the elastic body 1 and the inelastic bodies 2, 2 on both sides and the inelastic bodies 2, 2 in the vicinity. This causes deformation of the waveform, greatly reducing the anchoring area during anchoring, and therefore greatly reducing the anchoring force. When the fastening tape 11 provided with 3, 3, . . . is stretched, the cuts 3, 3, . The stress propagated to the joint was averaged, the deformation of the waveform during elongation as described above was significantly improved, the attachment area was also greatly improved, and a decrease in attachment retention force was prevented. Moreover, the end portion of the elastic body 1 is
If a minute scratch 13 is formed due to some reason during processing as shown by the dotted line in the figure, in the unbroken fastening tape 11 of FIG. 9, the scratch will enlarge due to repeated expansion and contraction during use, and eventually While the adhesive tape breaks, the cut 3,
A fastening tape 11 as shown in FIG. 1 provided with 3,...
In this case, the expansion of the wound was stopped at cut 3,
The fixing tape did not break. The present invention has been made based on the above findings, and includes at least one side of the same side of the two non-elastic bodies of a tape base material in which the center portion is made of a stretchable elastic material and both ends are made of an inelastic material. An elastic fastening tape comprising a fastening agent layer on each side,
The above object has been achieved by providing a stretchable fastening tape characterized in that the elastic body is provided with cuts in the stretching direction thereof. [Example] Hereinafter, the stretchable fastening tape of the present invention having the above characteristics will be explained with reference to the examples shown in the drawings. FIG. 1 is a plan view of an embodiment of the present invention before use, FIG. 2 is a longitudinal cross-sectional view thereof, FIG. 3 is a plan view when it is expanded, and FIGS. 4, 5, and 6 are respectively 3 are enlarged cross-sectional views taken along lines A-A, B-B, and C-C. In these drawings, 1 is a central portion made of an elastic body, 2, 2 is an end portion made of an inelastic body, The central portion (elastic body) 1 and both end portions (inelastic body) 2, 2 are integrally connected to form the tape base material 1.
It constitutes 0. The elastic body 1 is provided with cuts 3, 3, . . . extending through the thickness direction of the elastic body 1 in the stretching direction of the tape base material 10, that is, in the longitudinal direction in the case of the embodiment. Moreover, 4 and 4 are adhesive layers provided on the same side surfaces of the inelastic bodies 2 and 2 in the tape base material 10. The shapes of the cuts 3, 3, ... are linear in this embodiment, but they may be shaped like elongated slits of a constant width, or if the elastic modulus of the elastic body 1 is high or if the elastic body 1 is weak. When applying elastic force, the width of the elastic body between the slits may be made into a long slit shape with different widths so that it becomes narrower in the center, or a composite shape of this and a linear shape. The longer it is, the better. Furthermore, the lengths of the cuts 3, 3, . . . are not necessarily limited, and may extend to the region of the inelastic body. Preferably, the length is 50 to 100% of the length of the elastic body in the stretching direction, and it is preferably provided at the center of the elastic body. In addition, the distance between the cuts 3, 3, ... will vary depending on the use of the fastening tape and the strength of the elastic body, but it is important that the fastening tape is flexible, like a tape fastener for disposable diapers, and that it is flexible during use and processing. When the tape is used in applications where it is required to have stiffness, the thickness is preferably at least twice the thickness of the elastic body in terms of shape retention before use. Moreover, the intervals do not necessarily have to be equal as shown in FIG.
As shown in the figure, various changes can be made depending on the purpose, such as increasing the distance from both ends toward the center in the direction perpendicular to the contraction direction of the elastic body. In addition, the number of cuts 3, 3, ... mentioned above is determined based on the application of the adhesive tape, the strength of the elastic body, the width of the elastic body (length in the direction perpendicular to the stretching direction), the shape, length, interval, etc. of the cuts. Although it is determined as appropriate in consideration of the above, it is preferable that the number is 2 to 7. Further, the cuts 3, 3, . . . are preferably provided so that the elastic material does not substantially decrease, for example, from the viewpoint of strength and shape retention for fastening. Note that even if the cuts 3, 3, ... are formed in the elastic body before the elastic body and the inelastic body are integrally combined, they are formed in the elastic body after the elastic body and the inelastic body are integrally combined. It's okay. The material of the elastic body 1 is not particularly limited as long as it has a property called rubber elasticity, which deforms when stress is applied but recovers its shape when stress is removed. It can be molded using resins such as , urethane, and ester. The material of the inelastic body 2 is not limited as long as it requires a stress stronger than the elastic body 1 for deformation, and examples thereof include ordinary adhesive tapes such as polyethylene, polypropylene, nonwoven fabric, and paper. What is used as a tape base material or an elastic body 1
A composite sheet of the tape base material and the above-mentioned tape base material can all be used. Further, the elastic body 1 at the center and the inelastic bodies 2, 2 at both ends may be integrally connected, and there is no particular restriction on the joining method. In the above embodiment, as shown in FIG. 2, the center portion 1 of the tape base material 10 is formed only of an elastic material
Although both end portions 2, 2 are formed only from an inelastic material,
As shown in FIG. 8, a tape base material 10 is formed by disposing an elastic body from one end through the center to the other end, and disposing inelastic bodies on the front and back surfaces of each end of the elastic body. You may do so. However, in this case, it is preferable that the shrinkage rate or elastic modulus of the inelastic bodies disposed on the front and back surfaces be approximately the same in order to prevent deformation. Further, the adhesive layers 4, 4 are usually formed by applying a pressure-sensitive adhesive or an adhesive onto both end portions 2, 2. It should be noted that the adhesive layers 4, 4 may be provided on the entire surface of the tape base material if necessary, and, although not shown, may be provided on the other surface of the tape base material, especially on the surface of the inelastic body. Depending on the requirements, a back surface treatment layer can also be provided by coating silicone or the like. Furthermore,
The adhesive layers 4, 4 can also be provided on two inelastic opposite surfaces, respectively, if necessary. The fastening tape of the present invention configured as described above has the following features:
As mentioned above, when the elastic body 1 is stretched, the cuts 3, 3,... widen as shown in FIGS. 3 to 6, and the elastic body 1
The stress propagated to the joint between the material and the inelastic body 2, 2 is averaged, there is almost no curling or waveform deformation during elongation, the fixed area is large, and the fixed holding force does not decrease. Moreover, even if a minute flaw 13 is formed at the end of the elastic body 1 due to some reason during processing, as shown by the dotted line in FIG. This does not reach the point where the adhesive tape breaks. Therefore, the fastening tape of the present invention does not have drawbacks such as a decrease in the fastening force during use, breakage of the tape, and a decrease in productivity during processing, and has excellent fit to the body and comfortable fit when worn. It is. Note that the elastic fastening tape of the present invention is not limited to the above embodiments. Next, the effects of the elastic fastening tape of the present invention will be specifically explained using test examples. Test Example As shown in Figures 1 and 2, the center part 1 is formed of an elastic body made of styrene elastomer with a thickness of 300μ, a length of 10mm, and a width of 25mm.
Both end portions 2, 2 are formed of a non-elastic body made of a styrene elastomer and a polyester woven fabric with a width of 30 mm and a width of 25 mm, and a rubber adhesive layer with a thickness of 30 μ is provided on the same side of each of the non-elastic bodies. 4, 4 was formed, and cuts 3, 3, ... were formed in the elastic body through the thickness direction in the contraction direction, and the following test products 1 were prepared with different numbers and intervals of cuts.
-5 were produced. For these test products 1 to 5, the state of deformation during tension, the adhesion force of the tape, and the tensile breaking strength of the tape were observed and measured, and similar observations and measurements were made for the unbroken adhesion tape (comparative product). I took measurements. The results are shown in the table below. Test item 1: Two cuts are made so that the width of the elastic body is equally spaced (8.33 mm). Test item 2: The width of the elastic body is from one side to the other.
Test item 3: Two cuts were made at 5.0 mm, 15.0 mm, and 5.0 mm. Test item 4: Four cuts were made so that the width of the elastic body was equally spaced (5.0 mm). : The width of the elastic body is from one side to the other.
4 cuts were made at 3.0mm, 8.3mm, 8.3mm, 8.3mm, and 3.0mm Test item 5: 7 cuts were made at equal intervals (3.1mm) in the width of the elastic body. Comparison test item: Unbroken item

【table】

〔Effect of the invention〕

As mentioned above, when the elastic fastening tape of the present invention is stretched, the cut provided in the elastic body in the center expands, and the stress propagated to the joint between the elastic body and the inelastic bodies on both sides is averaged. The elastic material has almost no curl or wavy deformation when stretched, has a large attachment area, and has no reduction in attachment holding power.Moreover, the elastic body is free from minute scratches that may occur due to some reason during processing. Even if the tape is cut, the wound will stop expanding and the adhesive tape will not break, resulting in decreased adhesive strength during use, tape breakage, and reduced productivity during processing. It has no drawbacks and has great effects such as an excellent fit to the body and a comfortable feeling when worn.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention before use, FIG. 2 is a longitudinal cross-sectional view thereof, FIG. 3 is a plan view when it is expanded, and FIGS. 4, 5, and 6 are respectively FIG. 3 is an enlarged sectional view taken along lines A-A, B-B and C-C; FIG. 7 is a plan view of another embodiment of the present invention;
FIG. 8 is a longitudinal sectional view of yet another embodiment of the present invention, FIG. 9 is a plan view of the seamless fastening tape when it is contracted, FIG. 10 is a plan view when it is expanded, and FIG.
Figures 12 and 13 are D- in Figure 10, respectively.
FIG. 3 is an enlarged cross-sectional view taken along lines D, E-E, and F-F. 1... Central part (elastic body), 2... End part (inelastic body), 3... Cut, 4... Adhesive layer, 10...
Tape base material.

Claims (1)

[Claims] 1. A stretchable stopper comprising a tape base material having a center portion made of a stretchable elastic material and both ends made of an inelastic material, and an adhesive layer provided on the same side of at least the two non-elastic materials. It's wearing tape,
A stretchable fastening tape characterized in that the elastic body is provided with cuts in the stretching direction thereof.