JPH08154974A - Disposable diaper - Google Patents

Abstract

PURPOSE: To obtain a disposable diaper wherein a fastening tape is not bonded obliquely with respect to the width direction of the diaper and not peeled at the time of use by forming a mark line used when the fastening tape is bonded to the surface of a rear surface sheet. CONSTITUTION: A disposable sheet 1 has a liquid permeable surface sheet, a liquid impermeable sheet 3, an absorbing material 4, a fastening tape 10 for fixing the diaper at the time of wearing and a release tape folding back the fastening tape 10 at a folding-back part to bond a self-adhesive surface. The target tape bonding the fastening tape 10 is not attached on the surface of the rear surface sheet 3 and at least two mark lines 30 are provided to the surface of the rear surface sheet 3 at the proper position bonding the fastening tape 10 in parallel to the width direction of the diaper so as to be visually confirmed and the interval between the mark lines 30 is set to width equal to or more than that of the fastening tape 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disposable diaper, and more particularly, to a disposable diaper that does not have a target tape for adhering the fastening tape when the diaper is used, in which the adhesive strength of the fastening tape is properly exerted. The present invention relates to a disposable diaper that can and does not peel off the fastening tape during use.

[0002]

2. Description of the Related Art Disposable diapers that have hitherto been sold have been made by using a diaper by directly attaching a fastening tape for wearing a diaper on a back sheet. In the disposable diaper, the backsheet is torn during use, the fastening tape is dislodged, or the backsheet lacks flexibility.Therefore, most of the disposable diapers currently on the market are A reinforcing film (target tape) is used to fix the fastening tape. The purpose of the target tape is mainly to reinforce the back sheet when the fastening tape is attached to the back sheet to prevent the back sheet from breaking.

However, in the diaper using the above target tape, the fastening tape needs to be stuck on the target tape, but when the mother wears the diaper on the baby, the fastening tape is mistakenly stuck on the back sheet. , The problem of tearing the backsheet often occurs. Furthermore, the restriction of attaching the fastening tape onto the target tape is not preferable because it is restricted by the size adjustment of the diaper.

Therefore, in recent years, various disposable diapers without a target tape have been proposed and sold. However, in the disposable diaper that is not provided with the target tape, the user can easily adhere the fastening tape obliquely with respect to the width direction of the diaper, and when the oblique fastening tape is adhered in this manner, There is a problem that the adhesive force does not work properly and the fastening tape is easily peeled off during use of the diaper. Further, when the fastening tape is adhered, the fastening tape or the back sheet may be deviated, and the entire surface of the fastening tape may not be adhered to the back sheet, so that a non-adhesive portion (tack) may occur. In this way, when the non-adhesive portion is generated, the above problem becomes particularly remarkable.

Therefore, an object of the present invention is to prevent the fastening tape from sticking obliquely with respect to the width direction of the diaper when the user attaches the fastening tape to the back sheet, and the adhesive strength of the fastening tape is not increased. Is to provide a disposable diaper in which the fastening tape does not come off during use of the diaper.

[0006]

Means for Solving the Problems As a result of various studies on the disposable diaper having no target tape, the present inventors have found that the disposable diaper provided with a marking line for adhering the fastening tape to the surface of the back sheet. The inventors have found that the above object can be achieved and completed the present invention.

That is, the present invention relates to a liquid-permeable surface sheet,
A liquid-impermeable backing sheet and an absorber interposed between these sheets, a fastening tape for fixing the diaper at the time of wearing, and a fastening portion for folding the fastening tape when the fastening tape is not needed In a disposable diaper having a release tape for sticking the surface thereof, there is no target tape for sticking the fastening tape on the surface of the back sheet, and at least at an appropriate position for sticking the fastening tape on the surface of the back sheet. , At least two parallel marking lines are provided so as to be viewed parallel to the width direction of the diaper, and the distance between any two of the marking lines is equal to or larger than the width of the fastening tape. The present invention provides a disposable diaper having:

[0008]

The disposable diaper of the present invention has no target tape on the back sheet, and when used, the fastening tape and the back sheet are directly adhered to each other. At this time, two parallel marking lines, which serve as marks when the fastening tape is adhered to the surface of the back sheet, are provided so that the lines are parallel to the width direction of the diaper. The fastening tape does not stick diagonally to the width direction, and the fastening tape does not peel off during use of the diaper due to the proper adhesive force of the fastening tape.

[0009]

EXAMPLES The disposable diaper of the present invention will be described in more detail with reference to the accompanying drawings and will be specifically described by way of examples, but the present invention is not limited thereto. 1 is a perspective view showing the front side (abdominal side) of the diaper in one embodiment of the disposable diaper of the present invention.
FIG. 3 is a development view of the disposable diaper shown in FIG. 1.

As shown in FIGS. 1 and 2, the disposable diaper 1 of this embodiment includes a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, and an absorber 4 interposed between these sheets. A fastening tape 10 for fixing the diaper at the time of wearing, and a release tape (not shown) for folding the fastening tape 10 by a fold-back portion so that the adhesive surface 12 is adhered when the fastening tape 10 is unnecessary. Have. There is no target tape for adhering the fastening tape 10 on the surface of the back sheet 3, and at least two mark lines parallel to at least the proper position for adhering the fastening tape 10 on the surface of the back sheet 3. 30 is provided so as to be viewed parallel to the width direction of the diaper, and the gap between any two of the mark lines 30 has a width equal to or larger than the width of the fastening tape 10.

More specifically, in the disposable diaper 1 of this embodiment, as shown in FIGS. 1 and 2, the absorbent body 4 is curved and formed in an hourglass shape in which the crotch region is entangled, and the surface sheet 2 is provided.
Also, the crotch region of the backsheet 3 is also curved according to the shape of the absorber 4 as described above, and the absorber 4 is sandwiched and fixed by the topsheet 2 and the backsheet 3.
Moreover, when wearing a diaper, the front and rear waist portions 5, 5 ′ and the leg portions 6 in the peripheral edge portion of the absorbent body 4 are
An elastic stretchable member 7 for fitting the waist portions 5, 5 ′ and the leg portions 6 to the wearer is provided by being fixed by the topsheet 2 and the backsheet 3.

Next, the material for forming each member constituting the disposable diaper 1 will be described. Surface sheet 2 above
As the liquid permeable sheet that allows excrement to permeate into the absorbent body, it is preferable that it has a feeling close to that of underwear.As such a liquid permeable sheet, for example, woven cloth, nonwoven cloth, porous film and the like are preferable. Can be mentioned. In addition, a method of applying a hydrophobic compound such as a silicone oil or paraffin wax to the peripheral edge of the surface sheet 2 or a method of previously applying a hydrophilic compound such as an alkyl phosphate ester to the entire surface and washing the peripheral edge with warm water is performed. By applying a water repellent treatment, it is possible to prevent leakage due to bleeding of urine or the like at the peripheral edge.

Further, as the absorbent body 4, it is preferable to use a high molecular weight water-absorbing polymer mainly composed of defibrated pulp. The high-molecular water-absorbing polymer is the upper layer of the absorber 4,
It may be present in either the middle layer or the lower layer, or may be a mixture with pulp. Further, the high molecular weight water-absorbing polymer is preferably in the form of particles having a retaining property capable of absorbing and retaining a liquid 20 times or more its own weight and having a gelling property. ,
For example, starch-acrylic acid (salt) graft copolymer, saponified starch-acrylonitrile copolymer,
Preferable examples include crosslinked products of sodium carboxymethyl cellulose and acrylic acid (salt) polymers.

Further, as the elastic expansion / contraction member 7, thread rubber, flat rubber, film type rubber or film-like foamed polyurethane is preferably mentioned, and one having a stress of 40 to 150 g at 150% elongation is preferable. .

As the fastening tape 10, if the adhesive surface 12 is formed so as to satisfy the above-mentioned physical properties by using a rubber-based, acrylic-based or silicon-based adhesive, the composition of the adhesive, etc. Are not limited in any way, but as the rubber-based pressure-sensitive adhesive, for example, those mainly composed of natural rubber and synthetic rubber are used, and particularly from the viewpoint of pollution-free by hot melt coating and the like. , ABA type or AB type block copolymer (A is a thermoplastic block,
B is a rubber block, such as a styrene-isoprene-styrene copolymer, a styrene-butadiene-styrene copolymer, a styrene-ethylene-butadiene-styrene copolymer, a styrene-butadiene copolymer, or a hydrogenated product thereof. ) Is preferred.

Further, the above acrylic pressure-sensitive adhesive is not particularly limited, and for example, a soft main monomer having a low Tg which gives tackiness and a small amount of a hard comonomer having a high Tg which gives adhesiveness and cohesive force are crosslinked. Polymers and the like obtained by copolymerization with a functional group-containing monomer for improving adhesiveness are also used. Examples of the main monomer include ethyl acrylate (EA), butyl acrylate (BA), 2-ethylhexyl acrylate (2-EHA), and the like, and examples of the comonomer include vinyl acetate (VAc), acrylonitrile (AN), and acryl. Amide (AM), styrene (St), methyl methacrylate (MMA), methyl acrylate (MA) and the like can be mentioned. Examples of the functional group-containing monomer include methacrylic acid (MAA), acrylic acid (AA) and itaconic acid (IA). ), Hydroxyethyl methacrylate (HEMA), hydroxypropyl methacrylate (HPMA), dimethylaminoethyl methacrylate (DM), acrylate amide (AM), methylol acrylate amide (N-MAN), glycidyl methacrylate (GMA), anhydrous ma Such as in acid, and the like.

The thickness of the adhesive surface is not particularly limited, but usually 10 to 100 μm is suitable.

The film or tape as the base material is not limited in any way. For example, JP-A-63-112704.
The polypropylene-containing plastic described in Japanese Patent Laid-Open Publication, a laminate of polypropylene and polypropylene-containing plastic, or polyester is preferable, and the surface thereof may be a flat mat. Further, a foam or a base material having an uneven surface can also be used. Further, as the base material, olefin-based, styrene-based, urethane-based,
When a film containing a polyester elastomer as a main component is used, good slip properties can be exhibited, and the fastening tape can be made soft. The substrate thickness is preferably 50 μm to 150 μm in use.

The back sheet 3 is not particularly limited as long as it is formed so as to satisfy each of the above-mentioned physical properties, but a porous sheet having moisture permeability is preferable, and the back sheet 3 has a permeability of the porous sheet. Humidity is 0.5-4.0g / 1
It is preferably 00 cm ² · hr.

Here, the above-mentioned moisture permeability is obtained as follows. The moisture vapor transmission rate is determined according to JISZ-0208. Specifically, the following 1) device and equipment,
The following 4) operation is performed using 2) the preparation and 3) the test piece, and the following 5) is applied to the calculation.

1) Device and Equipment Moisture Permeation Cup Constant Temperature and Humidity Device: A device which is kept at a specified temperature and humidity and which allows air to circulate a test piece at a speed of 0.5 to 2.5 m / s. -Conditions in the above constant temperature and humidity apparatus: temperature 30 ° C, relative humidity 90 ± 2% (dry bulb 30 ° C, wet bulb 28.6 ° C) Balance: Balance capable of weighing up to 0.01 g Water bath desiccator fluid (American tailor (Tyler ) Standard sieve]
(7 mesh, 28 mesh)

2) Agents Absorbent: Calcium chloride (for U-shaped tube) with a particle size of 238
It passes 0μ (7 mesh) and stays at 590μ (28 mesh). Wax-sealant: paraffin wax 8 having a melting point of 50 to 52 ° C.
0WT% and viscous polyisobutylene (low degree of polymerization) 20W
T%. When using 10 moisture-permeable cups, weigh 160 g of paraffin wax and 40 g of viscous polyisobutylene. This is heated in a water bath and melt-mixed at about 100 ° C. to obtain a sealing wax. In addition, when using, about 6
It is used after being heated to 0 ° C to 70 ° C. n-Heptane: Used for removing the sealing wax adhered by the moisture permeable cup.

3) Test piece The test piece is a circular one having a diameter (about 70 mm) larger than the inner diameter of the moisture-permeable cup used, and four test pieces are cut out from the same sample to prepare for the test. The thickness of each test piece is measured at 5 places.

4) Operation The absorbent is placed in a moisture-permeable cup, the lid is covered with a ring provided with a test piece, and the molten wax is poured into a groove on the periphery of the cup to fix the moisture-permeable cup and the ring. , This is the test body. No. on the side of the moisture permeable cup. Fill in the box and weigh it after leaving it in the desiccator for 30 minutes.
_Set to ₀ . The test body is placed in a thermo-hygrostat maintained under predetermined test conditions, and after 1 hour, taken out and left in a desiccator. 5
The weight is taken out after a lapse of minutes, and this is designated as W ₁ .

5) Calculation The moisture permeability is determined by converting the weight change (W ₁ -W ₀ ) after 1 hour into a moisture-permeable area of 100 cm ² . The moisture permeable area of the moisture permeable cup is 28.27 cm ² . Moisture permeability = [(W ₁ -W ₀₎ /28.27] _{× 100 = (W 1 -W 0} ) × 3.54 [units (g / 100cm ² · 1hr)]

As the above-mentioned porous sheet, the following porous sheet having the above physical properties is particularly preferably used. At temperatures above the melting point of the crystalline polyolefin and the crystalline polyolefin, the crystalline polyolefin is miscible and melts, but at temperatures below the melting point of the crystalline polyolefin, phase separation occurs to the crystalline polyolefin. A solution consisting of the crystalline polyrefin and the compound is obtained by melt-mixing the compound that causes it, and a sheet is molded from the solution, and then the sheet is stretched in at least one direction to form micropores. Porous sheet.

In the crystalline polyolefin used in the porous sheet, the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is Mw / Mn> 5.0,
Preferred is polypropylene having Mw / Mn> 6.0. Here, the above-mentioned ratio is an index showing the distribution of the molecular weight, and when the above-mentioned ratio is Mw / Mn> 5.0, for example, when the above-mentioned polypropylene is melt-mixed with 20% by weight or more of mineral oil, the above-mentioned polypropylene It is preferable that the above-mentioned ratio is Mw / Mn> 5.0, since the above-mentioned mineral oil can be quickly dissolved and can be stably mixed.

The weight average molecular weight of the polypropylene is preferably in the range of 300,000 to 600,000, and the melting point thereof is preferably in the range of 155 to 170 ° C. The polypropylene may be a homotype, a block type, or a random type, and these may be used alone or in combination of two or more kinds, and further, other resins such as polyethylene may be mixed and used.

In addition, since the polypropylene exhibits high crystallinity and the rigidity is improved, the polypropylene also satisfies the above ratio, and further, the isotactic pendat fraction (P) and the melt index (P). MI) and 1.00 ≧ P ≧ 0.015LogMI + 0.955
It is particularly preferable that the relationship Here, the isotactic pendat fraction (P) is an index showing the crystallinity of polypropylene.

The MI is 0.03 to 2.0 g /
It is preferably in the range of 10 minutes. The MI is 0.0
When it is less than 3, the fluidity of the melt at the time of granulation or molding is poor, which requires power and is not economical, and the production speed cannot be increased. When it exceeds 2.0, melting occurs. The tension is reduced, and when the sheet is formed by, for example, the inflation method, it is difficult to lift the bubbles and the formation becomes unstable, so that the above range is preferable.

The above-mentioned compound is not particularly limited as long as it has the above-mentioned characteristics, but specifically, mineral oil such as liquid paraffin, synthetic lubricating oil, dioctyl phthalate, diethyl phthalate, triethylene glycol, dibutyl. Phthalate, and esters of phthalic acid, trimellitic acid, pyromellitic acid and / or an aliphatic polybasic carboxylic acid with an alkyl alcohol, and the like are preferable.

In the porous sheet, the blending ratio of the crystalline polyolefin and the compound is 30 to 90 parts by weight of the crystalline polyolefin, preferably 60 to 8 parts.
The amount of the compound is 70 to 10 parts by weight, preferably 40 to 20 parts by weight, based on 0 parts by weight.

The mixing ratio of the crystalline polyolefin is 3
If the amount is less than 0 parts by weight, the shapeability of the sheet obtained by stretching is poor because the proportion of the resin that serves as the matrix is small, and when the material is rolled, the fine pores are crushed and liquid such as mineral oil oozes out. When the amount exceeds 90 parts by weight, it may not be possible to form the fine pores that impart moisture permeability even when stretched. Therefore, it is preferable to use the above mixing ratio. .

The temperature at the time of melt mixing is not less than the melting point of the crystalline polyolefin, preferably in the range of 180 to 250 ° C. To obtain the solution by melt mixing, a biaxial kneader is used. It can be obtained by a method in which the polypropylene pellets are quantitatively fed from a hopper and fed, and the compound is injected from the vent hole of the biaxial kneader.

In order to form the sheet, the solution is once cooled to prepare compounded pellets, which are then inflation-molded from a circular die using a single-screw extruder, or biaxial. This can be carried out by a method such as inflation molding using a kneader and a circular die connected to the tip of the kneader via a gear pump.

Further, when forming the above-mentioned sheet, the following various additives can be added, if necessary, within the range of the following addition amount. Controlling the crystal size of polypropylene such as p-tert-butylbenzoic acid aluminum salt, 1,2,3,4-dibenzylidene sorbitol, 1,2,3,4-di- (p-ethylbenzylidene) sorbitol The crystal nucleating agent was added to the above solution in an amount of 0.
5% by weight or less; 1% by weight or less of an inorganic filler for preventing tearing, such as anhydrous silica and zeolite, with respect to the entire solution; an inorganic filler that imparts concealing properties such as titanium oxide, barium sulfate, calcium carbonate, and talc; the above solution 20% by weight or less based on the whole; coloring agents such as phthalocyanine blue, quinacdrine red, dioxane violet and isoindolinone; 0.05% by weight or less based on the entire solution. When the crystal nucleating agent is added, it is preferably added as a crystal nucleating agent masterbatch.

The stretching ratio in the above stretching is 1.2.
~ 3 times, the stretching temperature is preferably 10 ~ 80 ℃,
The stretching direction may be either uniaxial or biaxial.
The micropores formed by the stretching have a pore diameter of 0.0
It is preferably 5 to 1 μm.

The back sheet 3 preferably has a load of 100 g / cm to 300 g / cm, and more preferably 100 g when stretched by 3% in the width direction of the disposable diaper.
/ Cm to 200 g / cm, the bulk softness is preferably 55 g or less, more preferably 45 g or less, most preferably 10 to 30 g, and the breaking strength is preferably 250 g.
/ Cm or more, more preferably 400 g / cm or more, and most preferably 500 g / cm or more. The fastening tape 10 has a 180 ° peeling force with respect to the back sheet 3 (adhesion to the back sheet, 40 ° C. 80%. The peel strength after 24 hours at RH) is preferably 400 g / cm or less, more preferably 150 to 300 g / cm, and 50
The holding time under a 0 g load is preferably 10 minutes or longer, more preferably 30 minutes or longer, and most preferably 60 minutes or longer.

If the load is less than 100 g / cm, the backing sheet is apt to be overextended when the fastening tape is loaded while the diaper is attached, and the fastening tape cannot follow the extension of this portion. It may come off or the stretched part may be torn, 300 g / cm
If it exceeds, the back sheet is difficult to stretch, so that it is not possible to follow the movement of the wearer's body, and the wearing feeling is poor. If the bulk softness exceeds 55 g, the flexibility of the back sheet is poor, and the entire diaper feels stiff and the feel is poor, so
It is preferably within the above range. The breaking strength is 250
If it is less than g / cm, the back sheet will be broken when the fastening tape is attached to the back sheet and the fastening tape is peeled off after the diaper is put on. Therefore, the back sheet is preferably in the above range. The 180 ° peel force is 40
When it exceeds 0 g / cm, when the above-mentioned fastening tape is attached to the back sheet, the back sheet will be broken when the fastening tape is peeled off after the diaper is attached, so the back sheet is preferably in the above range. If the holding time is less than 10 minutes, the wearer moves violently while wearing the diaper,
When the person sits down, stress is applied to the fastening tape, and the fastening tape may come off, causing leakage of excrement.

Here, each of the above physical properties is obtained as follows. 1. Load measuring device for 3% elongation of back sheet Tensilon universal tester / tensile test mode (manufactured by Orientec Co.) Sample As shown in FIG.
Sampling at different locations (at this time, if adhesive, backing paper, etc. adheres to the back sheet, wipe it off with an organic solvent such as toluene so that it does not affect the back sheet). At this time, the size of each sampled sample is 10 mm.
X (25 mm + 50 mm + 25 mm) [see FIG. 3]. Measurement conditions (1) Measurement environment: temperature 20 ° C, humidity 65
% RH (2) Tensile condition: Distance between chucks 50 mm Tensile speed 300 mm / min Measurement result 3% elongation (when the distance between chucks 50 mm became 51.5 mm) was measured for tensile strength for each of five samples, Calculate the average.

2. Bulk softness measuring device Tensilon universal testing device / compression test mode (manufactured by Orientec Co.) Sample (1) For sampling location, see 1. It is the same as the sampling location under the load when the back sheet is stretched by 3%, but the dimensions of the sample are
The size is 30 mm × 150 mm. (2) Measurement sample: As shown in FIG. 4 (a), using each sampled sample, a cylinder a having a surface of 45 mm in diameter (outer surface side of the diaper) as the outside is formed, and the upper and lower ends of the overlapped portions are formed. Staple and stop. Then
A vinyl chloride ring b shown in FIG. 4 (b) is applied to the lower portion of the cylinder a: a measurement sample c shown in FIG. 4 (c). Measurement conditions (1) Measurement environment: temperature 20 ° C, humidity 65
% RH (2) Compression condition: compression speed 10 mm / min Measurement result The maximum strength when the sample was compressed by 20 mm was measured for each of the five samples, and the average thereof was calculated to obtain the bulk softness.

3. Breaking strength A test was conducted in the same manner as in "1. Measurement of load when the backsheet is stretched by 3%", the load at the time of breaking was determined, and the load was defined as the breaking strength.

4. Holding time measuring device Holding force tester with constant temperature chamber (manufactured by Tester Sangyo Co., Ltd.) Sample As shown in FIG. 5, the back sheet was sampled at 6 points from the diaper (at this time, the adhesive and the backing sheet adhered to the back sheet). In this case, the adhesive, the mount, etc. are removed with an organic solvent such as toluene to such an extent that the back sheet is not affected). At this time, the size of the sampled sample is 100 mm × 100 mm. Measurement conditions (1) Measurement environment: temperature 40 ° C. (2) Load condition: 500 g Measurement results As shown in FIG. 6, a fastening tape was attached to the sample so that the adhesion area (hatched portion in FIG. 6) was 25 mm × 30 mm. Affixing and applying a load of 500 g in the vertical direction (the direction of the arrow shown in FIG. 6), the holding time is measured for each of the six samples, and the average thereof is determined. still,
At this time, the fastening tape was adhered in the width direction (arrow direction shown in FIG. 5) in the diaper of each sample before sampling for evaluation, and the fastening tape was adhered by reciprocating a 200 g rubber roller once. went.

5. 180 ° Peeling Force An acrylic plate (5 mm × 125 mm × 3 mm) was pasted with a double-sided tape (MD30 mm), and the back sheet was further stuck thereon without damaging the adherend, as shown in FIG. 7 (a). Then, a fastening tape is attached to the adherend as shown in FIG.
As shown in (b), only 25 mm x 20 mm is adhered,
A 25 mm wide 1 kg rubber roller was reciprocated and crimped once, then stored at 40 ° C. and 80% RH for 24 hours, and allowed to stand at room temperature for 30 minutes, and a 180 ° peeling test was performed under the following conditions. The adhesive strength (g / 25 mm) of the fastening tape to the back sheet is obtained. The measurement is carried out on five samples, and the average value is shown.
The measured value is converted into a 10 mm width of the tape after the measurement [actual measured value × (10/25)]. Measuring device Tensilon universal tensile test device Sample For the sampling location and sample dimensions, see [1. The load at the time of stretching the back sheet by 3%] and the dimensions of the sample (150 × 50 mm). Measurement conditions [1. Load under 3% extension of back sheet]. Measurement Results The average peel force of the five samples measured as described above is determined.

Thus, in the disposable diaper of the present invention, there is no target tape for adhering the fastening tape 10 on the surface of the back sheet 3, and the diaper at the proper position is attached to the user. 2 parallel to the left and right sides of the waist circumference located around the wearer's waist when worn on the abdominal side of the wearer.
A book marking line 30 is provided parallel to the width direction of the diaper. In this embodiment, two mark lines are provided on each of the left and right sides, for a total of four mark lines, but two mark lines may be provided so as to cross the width direction of the diaper.
Also, three or more may be provided. When three or more lines are provided, any two of the mark lines may have a width equal to or larger than the width of the fastening tape.
When three mark lines are provided above, in the middle, and below in the width direction of the diaper, the distance between the upper mark line and the lower mark line should be greater than the width of the fastening tape. The distance between the upper marking line and the middle marking line and the distance between the middle marking line and the lower marking line may be smaller than the width of the fastening tape.

In the present embodiment, the distance between the two marking lines 30 has a width equal to or larger than the width of the fastening tape 10. Specifically, as shown in FIG. 2, the distance L between the two marking lines 30 and the fastening tape 10 are set.
The ratio of the width L to the width M is 1.0 to 3.
It is preferably 0.

Next, the following test examples 1 to 5 were performed to confirm the ease of peeling of the fastening tape when the fastening tape was applied parallel to the width direction of the diaper and when it was applied obliquely.

[Test Example 1] A sheet prepared by laminating an OPP (20 μ) sheet with an adhesive so as not to extend to the porous polypropylene sheet (35 μm) used as the back sheet 3 of the diaper, has a size of 120 mm × 120 mm. Then, the test backsheet 3 shown in FIG. 8A was prepared. Further, using an acrylic pressure-sensitive adhesive as the pressure-sensitive adhesive, three kinds of fastening areas 10 having a thickness of the adhesive surface of 12 μm, 15 μm, and 17 μm and having an adhesive area of width 33 mm × length 35 mm were prepared. Then, the obtained fastening tapes 10 were attached in parallel (toward the width direction when attached to the diaper) to the test backsheet 3 as shown in FIG. A test sample of the seed was obtained. Using the obtained test sample, the shearing force and the holding force were measured as follows. The results are shown in [Table 1].

( Shearing force ) Measuring device Tensilon universal device / tensile test mode (manufactured by Orientec Co.) Sample Measuring conditions for the above test (1) Measuring environment: temperature 20 ° C., humidity 65
% RH (2) Tensile conditions: Distance between chucks 50 mm Tensile speed 10 mm / min Measurement results Figure 8 for fastening tape
The direction of arrow A shown in (a), and arrow B for the back sheet
The maximum value of the tensile strength when the both are pulled in the direction is measured, and the average thereof is obtained (n = 5).

( Holding power ) Measuring device Holding power tester with constant temperature chamber (manufactured by Tester Sangyo Co., Ltd.) Sample Measurement conditions for the above test (1) Measurement environment: temperature 40 ° C (2) Load condition: 500 g Measurement results Fastening tape 500 g in the vertical direction [arrow A direction shown in FIG. 8 (a) for fastening tape, arrow B direction for back sheet]
The load is applied, the retention time is measured for each sample, and the average is obtained. The fastening tape was adhered by reciprocating once with a 200 g rubber roller.

[Test Example 2] Shearing force and holding force were measured in the same manner as in Test Example 1 except that the width of the fastening tape 10 was 28 mm. The results are shown in [Table 1].

Test Example 3 As shown in FIG. 8 (b), the test back sheet 3 was attached obliquely (tilted at an angle of 20 °), and for the fastening tape, as shown in FIG. 8 (b). The shearing force and the holding force were measured in the same manner as in Test Example 1 above except that both were pulled or a load was applied in the direction of arrow C and in the direction of arrow D for the back sheet. The results are shown in [Table 1].

[Test Example 4] As shown in FIG. 8C as the fastening tape 10, the adhesive surface 13 formed by applying the adhesive and the non-adhesive surface 1 not coated with the adhesive.
Shearing force and holding force were measured in the same manner as in the above-mentioned Test Example 1 except that the fastening tape 10 'in which 2 and 2 were alternately provided was used. The results are shown in [Table 1]. In addition, 11 is a picking portion of the fastening tape. Further, the fastening tape 10 'is assumed to have a non-adhesive portion (tack) when actually using the diaper.

Test Example 5 As shown in FIG. 8 (b), the test back sheet 3 was attached obliquely (at an angle of 20 °), and for the fastening tape, as shown in FIG. 8 (b). The shearing force and the holding force were measured in the same manner as in Test Example 4 above except that both were pulled or a load was applied in the direction of arrow C and in the direction of arrow D for the back sheet. The results are shown in [Table 1].

[0055]

[Table 1]

As is clear from the above Test Examples 1 to 5,
When the fastening tape is attached obliquely to the back sheet, the shearing force and the holding force are lower than when the fastening tape is attached parallel to the back sheet, and this tendency is When it occurs, it can be seen that it becomes particularly remarkable. Since the disposable diaper of the present invention employs the above-mentioned configuration, it is possible to effectively prevent the fastening tape 10 from being adhered obliquely to the width direction of the diaper, and the adhesion of the fastening tape 10 Even when the adhesiveness of the fastening tape 10 is accompanied by a non-adhesive portion, the force can be appropriately applied to prevent the fastening tape 10 from peeling off during use of the diaper. Further, the target tape means a tape or the like provided on the surface of the back sheet for attaching the fastening tape in the conventional disposable diaper.

The disposable diaper of the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the marking line may be provided by attaching a colored tape to the back side of the back sheet (that is, the absorber side). In this case, the left and right edges of the colored tape can be visually recognized as the mark lines, and the colored tape itself can be visually recognized as the mark lines. The colored tape may be an OPP film, P having a thickness of 15 μm to 50 μm.
ET film, PP film, polyethylene film,
An example is a colored tape formed by coloring a film such as a film formed by blending polypropylene and polyethylene.

[0058]

EFFECTS OF THE INVENTION The disposable diaper of the present invention does not stick the fastening tape obliquely with respect to the width direction of the diaper when the user sticks the fastening tape to the back sheet, and does not stick the fastening tape. The fastening tape does not come off when the diaper is used by applying force properly.

[Brief description of drawings]

FIG. 1 is a perspective view showing a front side (abdominal side) of a diaper in an embodiment of a disposable diaper of the present invention.

FIG. 2 is a development view showing the back sheet side of the disposable diaper shown in FIG. 1 in a developed state.

FIG. 3 is a schematic diagram showing sampling locations and sample dimensions when measuring a load at 3% extension.

FIG. 4 is a schematic view showing an aspect of forming a measurement sample when measuring bulk softness.

FIG. 5 is a schematic diagram showing sampling locations when measuring retention time.

FIG. 6 is a schematic diagram showing an aspect of measuring a retention time.

FIG. 7 (a) is a plan view showing an adherend to be made when measuring a 180 ° peeling force, and FIG. 7 (b) is a plan view showing a case in which a fastening tape is adhered onto the adherend. It is a side view which shows the aspect.

8A and 8B are schematic diagrams showing a test sample used in a test example, and FIG.
It is a top view which shows the adhesive surface side of the fastening tape used in Test Examples 4 and 5.

[Explanation of symbols]

 1 Disposable diapers 2 Top sheet 3 Back sheet 4 Absorber 5 Waist section 6 Leg section 7 Elastic elastic member 10 Fastening tape 30 Marking line

Claims (1)

[Claims] 1. A liquid-permeable top sheet, a liquid-impermeable back sheet, an absorbent body interposed between these sheets, and a fastening tape for fixing a diaper during wearing,
In a disposable diaper having a release tape for folding the fastening tape by a folding portion when the fastening tape is not needed and for sticking the adhesive surface thereof, a target tape for sticking the fastening tape on the surface of the back sheet. Rather, at least two parallel marking lines are provided so as to be visually recognized in parallel to the width direction of the diaper at a proper position where the fastening tape is adhered on at least the surface of the back sheet. The distance between the two marking lines is equal to or larger than the width of the fastening tape.