JPH0568518U - Disposable diaper - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] When a defective product occurs in the binding tape of a diaper, it is reliably detected in the manufacturing process. [Structure] A defective product is detected by using an image sensor by setting the opacity of the bonding tape and the peeling tape in a state of being bonded to each other from 40 to 65%.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 Used diapers. More specifically, the present invention relates to a disposable diaper in which the detection rate of products in which the bonding tape portion is in a defective state is significantly improved as compared with the conventional one.

[0002]

[Prior Art]

 Conventional disposable diapers are equipped with a tape structure at both waists to connect them. This tape structure has a pressure-sensitive bonding tape, and in general, this bonding tape is fixed at one end to the back sheet on both sides of the waist of the diaper on the back side and at the opposite side to the top sheet. The free end of the binding tape is temporarily attached to the peeling tape, and the free end of the binding tape is peeled off from the peeling tape at the time of use and adhered to the back sheet on both sides of the front side waistline. The waist and both ends of the front side and the back side are connected.

When the bonding tape is peeled off from the peeling tape, the tip of the free end of the bonding tape is generally bent about 3 to 10 mm with the adhesive surface inside so as to facilitate peeling. Therefore, the joining tape is doubled at the tip of the free end. The steps of attaching the above tape structure to the diaper are as follows. (1) Fold the binding tape so that one side edge is 3 to 10 mm and the adhesive layer is inside. (2) The joining tape is attached to a peeling tape having a width narrower than that of the joining tape so that the peeling tape is located on the bent side edge of the joining tape. (3) Cut the bonded release tape and bonding tape laterally to a predetermined size. (4) With the adhesive surface of the peeling tape, the small pieces of the cut tape are such that the bonding tape portion protruding from the peeling tape is exposed outside from the side edge of the top sheet, that is, the side edge of the diaper. Stick on the front side of. (5) Bend the bonding tape portion protruding outside from the side edge of the diaper to the back sheet side, and bond it to the back sheet. Since all of the above steps are performed at a high speed, a slight dimensional deviation may occur in each step, or the tape may drop off in the attaching step. In order to detect these defective products, intermittent visual inspections by personnel or automatic inspections using image analysis devices are performed.

In this automatic inspection system, a strobe and a camera are integrated, the light emitted from the strobe is applied to a diaper, the intensity of the transmitted light is detected by the camera, and the signal is input to an image analysis device to determine whether it is a normal product. It is a system that detects the difference between Therefore, dropout of the tape, displacement from a predetermined position, change in the shape of the tape due to abnormal cutting, etc. are detected in advance, and the number of defective products shipped is greatly reduced.

However, there are some defective states that are difficult to detect in advance. For example, when the tip of the binding tape is not folded, the adhesive surface of the binding tape directly adheres to the surface sheet and does not serve as the binding tape. Further, when the bonding tape and the peeling tape are not aligned with each other and the adhesive surface of the bonding tape protrudes between the tab of the bonding tape and the peeling tape, the adhesive surface of the bonding tape directly adheres to the surface sheet. Does not serve as a binding tape. These are difficult to detect because the tabs are not visible through the tie tape and the release tape under the tie tape is not visible.

[0006]

[Problems to be solved by the device]

 If the binding tape tip is not folded properly, that is, if the tab is defective, or if the bonding tape and the peeling tape are misaligned, the tab cannot be seen through the bonding tape and the peeling tape under the bonding tape cannot be seen. Difficult to detect.

[0007]

[Means for Solving the Problems]

 In a bonding tape structure used for a disposable diaper having a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body between these sheets, the bonding tape structure is composed of a bonding tape and a peeling tape, and the bonding tape is One end thereof is attached to the back sheet at both ends of the back side of the diaper or between the back sheet and the top sheet, and the release tape is attached to the top sheet corresponding to the surface opposite to the attaching position of the bonding tape. When the total opacity of the base material layer and the pressure-sensitive adhesive layer of the bonding tape is 40% to 65%, the above problem can be solved.

The present invention will be described in detail below. The materials used in the present invention are all commonly used. The surface sheet is made of polypropylene, polyester or the like, a card method, a spunbond method or other non-woven fabric, and the back sheet is made of polyethylene or the like. A waterproof film or a breathable microporous film containing fine particles of pigment is used. The absorbent body consists of water-absorbent paper, fluff pulp, super absorbent polymer, etc., alone or in a mixture, and the stretchable elastic body is made of natural rubber thread rubber, synthetic rubber thread rubber, elastic polyurethane rubber (spandex) elastic polyurethane. Films, polyurethane foams, etc. can be used. The release tape substrate is generally a polypropylene film, but may be a polyethylene film or the like. The release tape preferably has a high opacity so that it can be easily detected, and is subjected to pigment kneading or printing treatment.

A polypropylene film is generally used as the base material of the bonding tape, but a polyethylene film or the like may be used as well as the release tape. In order to put the opacity of the binding tape in the range of 40% to 65%, a predetermined amount of pigment is kneaded into the film, lightly printed, or the adhesive is mixed with a predetermined amount of pigment. When the opacity of the bonding tape is out of the above range, the bonding tape itself becomes difficult to detect at 40% or less, and the peeling tape or the tab under the bonding tape cannot be detected at 65% or more.

The opacity is measured as follows. Measuring instrument SM Color Computer Model SM-4 (Suga Test Instruments Co., Ltd.), under the conditions of reflected light and light source window diameter of 12 mm, one sample on a white plate, blackboard (white plate, blackboard is a Hunter whiteness meter Measure the Y value with the standard plate for opacity measurement used), and calculate as follows. Y value on white board Y1 Y value on blackboard Y2 Opacity (%) = Y2 / Y1 × 100

Example 1 Bonding Tape (Opacity 55%) Base Material Polypropylene Film 100μ (Titanium Dioxide 0.5% Blend) Adhesive (Rubber-Based, No Pigment Additive) 30μ Coating Release Tape (Opacity 87%) Base Material Polypropylene film 25μ (white printing) Adhesive (rubber-based, non-pigmented) 40μ coating Surface sheet Polypropylene spunbond 25g / m ² Back sheet Polyethylene film 25μ Absorber NBKP fluff mat 400g / m ² Using each of the above materials The tape was combined with the normal state shown in FIG. 3 and the defective state shown in FIG. 4 to prepare two types of diapers.

Comparative Example 1 Bonding Tape (Opacity 85%) Base Material Polypropylene Film 100μ (White Printing) Adhesive (Rubber-based, No Pigment Additive) 30μ Coating Release Tape (Opacity 87%) Base Material Polypropylene Film 25μ ( White printing) Adhesive (rubber-based, non-pigmented product) 40μ coating Top sheet polypropylene Spunbond 25g / m ² Backsheet polyethylene film 25μ Absorber NBKP fluff mat 400g / m ² Using each of the above materials, tape as shown in Fig. 3 Two types of diapers were prepared by combining the normal state of Fig. 4 and the defective state of Fig. 4. FIG. 4 shows a state in which a part of the binding tape protrudes from the binding tape (5-2 ′) on the top sheet (2) and is bonded to the top sheet, and does not serve as a binding tape.

The following are the results of an attempt to distinguish between a normal product and a defective product of the above diaper by an image sensor system (manufactured by Kodak Co.). (Discrimination result between normal product and defective product) Example 1: Discrimination is possible Comparative example 1: Discrimination is not possible

[0014]

[Effect of the device]

 As described above, according to the present invention, by controlling the opacity of the bonding tape to be 40% to 65%, it is possible to efficiently detect the poor bonding of the bonding tape and the peeling tape, which was difficult to detect in the past. Became.

[0015]

[Brief description of drawings]

FIG. 1 is a plan view showing an example of a disposable diaper.

FIG. 2 is an enlarged view of the joining tape portion of the disposable diaper,

FIG. 3 is a sectional view taken along line X1-X2 in FIG. 2 showing a normal state.

4 is a cross-sectional view showing another example taken along line X1-X2 in FIG. 2, showing a defective state.

[Explanation of symbols]

 1: Disposable diaper 2: Top sheet 3: Back sheet 4: Absorber 5: Bonding tape 5-1: Bonding tape base material 5-2: Bonding tape Adhesive 5-2 ': Bonding tape Adhesive protrusion part 6: Peeling off Tape 6-1: Peeling tape Base material 6-2: Peeling tape Adhesive 7: Bonding tape tab 8: Bonding tape adhesive sheet 9: Stretchable elastic body

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fukuhito Matsumoto 1-10-6 Shinonome, Koto-ku, Tokyo Oji Paper Co., Ltd. Research Center

Claims (1)

[Scope of utility model registration request] 1. A bonding tape structure for use in a disposable diaper having a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body between these sheets, wherein the bonding tape structure is a bonding tape and a peeling tape. The binding tape is attached to one end of the back sheet at both ends of the back side of the diaper, or between the back sheet and the top sheet,
The release tape is attached to a surface sheet corresponding to a surface opposite to the attachment position of the binding tape, and the opacity of the base layer and the pressure-sensitive adhesive layer of the binding tape is 4 when measured together.
A disposable diaper characterized by 0% to 65%.