WO2022065488A1

WO2022065488A1 - Joint structure

Info

Publication number: WO2022065488A1
Application number: PCT/JP2021/035398
Authority: WO
Inventors: 亮介大和; 晃一斉藤; 聡一郎小宮; 和樹久野; 梨佳末
Original assignee: 昭和電工マテリアルズ株式会社
Priority date: 2020-09-28
Filing date: 2021-09-27
Publication date: 2022-03-31
Also published as: CN116209368A; JPWO2022065488A1; TW202222190A

Abstract

A joint structure 1 obtained by joining stretchable materials 2, 2 with a bonding portion 3 having a predetermined pattern. The bonding portion 3 extends in a dashed line shape as a whole with an extending axis P along a stretching direction T1 of the stretchable material 2. Each dash part 5 of the bonding portion 3 intersects the extending axis P.

Description

Joined structure

This disclosure relates to a joint structure.

As a conventional bonding structure, for example, there is a method of bonding elastic materials described in Patent Document 1. This conventional bonding structure is a structure in which elastic materials are bonded to each other in a predetermined bonding pattern using an adhesive. The adhesive pattern has an adhesive portion that continuously adheres elastic materials to each other. The adhesive portion is continuously provided in the edge direction of the elastic material by a pattern such as a zigzag shape.

Japanese Unexamined Patent Publication No. 2004-11056

In the joining structure as described above, it is necessary to secure sufficient joining strength without impairing the elasticity of the stretchable material to be bonded. Further, from the viewpoint of cost reduction of the joining structure, it is desirable to reduce the amount of the adhesive required for joining.

The present disclosure has been made to solve the above problems, and it is intended to provide a bonding structure capable of sufficiently ensuring both the elasticity and the bonding strength of the elastic material while reducing the amount of the adhesive used. The purpose.

The bonding structure according to one aspect of the present disclosure is a bonding structure in which elastic materials are bonded to each other by an adhesive portion having a predetermined pattern, and the adhesive portion as a whole has an extending axis along the expansion and contraction direction of the elastic material. It extends in a broken line shape, and each broken line portion of the adhesive portion intersects the extending axis.

In this joint structure, the stretchable material extends in a broken line shape with an extension axis along the expansion / contraction direction as a whole. Therefore, the adhesive portion and the non-adhesive portion are alternately arranged in the expansion / contraction direction of the elastic material. Since the non-adhesive portion where the adhesive portion is not located serves as a stretch margin for the elastic material, sufficient elasticity of the elastic material can be ensured. Further, in this joint structure, each broken line portion of the bonded portion intersects the extending axis. Therefore, the regions in which the adhesive portions and the non-adhesive portions are alternately arranged are formed with a constant width in the direction intersecting the elastic direction of the elastic material, and the bonding hardness of the elastic material can be sufficiently secured. Since the adhesive portion has a broken line shape, the amount of the adhesive used is reduced as compared with the case where the adhesive portion is continuously provided.

In the bonded portion, the positions of the groups of the broken lines adjacent to each other in the extending axis direction may be reversed with respect to the extending axis. In this case, since the arrangement of the adhesive portions is symmetrical with respect to the extending axis, it is possible to suppress the deviation of the elasticity and the bonding strength in the region where the adhesive portions and the non-adhesive portions are alternately arranged.

In the bonded portion, the positions of the broken line portions adjacent to each other in the extending axis direction may be inverted with respect to the extending axis. In this case, since the arrangement of the adhesive portions is symmetrical with respect to the extending axis, it is possible to suppress the deviation of the elasticity and the bonding strength in the region where the adhesive portions and the non-adhesive portions are alternately arranged.

Each broken line portion of the bonded portion may extend in a direction orthogonal to the extending axis. In this case, the bonding hardness of the stretchable material can be further sufficiently secured.

The adhesive portion may have a zigzag shape as a whole. This makes it possible to easily form an adhesive portion that satisfies the above structure.

The adhesive portion may be composed of a hot melt adhesive. The hot melt adhesive is a solvent-free adhesive and has an advantage that the load on the environment and the human body is small. In addition, since it can be bonded in a short time, it contributes to improving the productivity of the bonded structure.

According to the present disclosure, it is possible to sufficiently secure both the elasticity and the bonding strength of the elastic material while reducing the amount of the adhesive used.

It is sectional drawing which shows the joint structure which concerns on one aspect of this disclosure. It is a top view which shows an example of the pattern of the adhesive part. It is a top view which shows another example of the pattern of the adhesive part. It is a top view which shows another example of the pattern of the adhesive part. It is a top view which shows the structure of the sample in stretchability evaluation. It is a figure which shows the evaluation test result of elasticity and adhesive strength in each pattern of an adhesive part.

Hereinafter, preferred embodiments of the joining structure according to one aspect of the present disclosure will be described in detail with reference to the drawings. In the present specification, the numerical range indicated by using "-" includes the numerical values before and after "-" as the minimum value and the maximum value, respectively.
[Joining structure]

FIG. 1 is a cross-sectional view showing a joint structure according to one aspect of the present disclosure. As shown in the figure, the bonding structure 1 is a structure in which a pair of

elastic materials

2 and 2 are bonded by an adhesive portion 3. Here, the stretchable material 2 is a stretchable fabric used for, for example, sportswear, innerwear, and the like. As the stretchable fabric, a knitted fabric or a woven fabric having elasticity can be used. Examples of the material of the elastic fabric include polyester, polyurethane, acrylic, cotton, nylon, and a composite fabric in which these are combined. The

elastic materials

2 and 2 may be the same material or may be different materials from each other.

One direction in the in-plane direction of the stretchable material 2 is the stretchable direction T1 of the stretchable material 2. The degree of elasticity of the elastic material 2 in the expansion / contraction direction T1 is not particularly limited, and may have any elasticity. The stretchable material 2 may have elasticity in a plurality of in-plane directions of the stretchable material 2. In this case, one of the plurality of directions may be defined as the expansion / contraction direction T1.

The adhesive portion 3 is composed of, for example, a hot melt adhesive, and is arranged between the

elastic materials

2 and 2 with a predetermined pattern. The adhesive portion 3 realizes a non-sewn joint of the

elastic materials

2 and 2. In the non-sewn joint, since the sewing thread is not used, it is easy to secure the elasticity at the joint portion. In addition, since the fabric does not fray due to the sewing thread, it becomes easier to maintain the aesthetic appearance of the joined portion as compared with the joining by sewing. Joining with a hot melt adhesive is easier to apply when the joined part is curved than joining with a conventional adhesive tape, and it is not necessary to apply high pressure at the time of joining. , The reliability of the bonding structure 1 after bonding can be improved.
[Hot melt adhesive]

The hot melt adhesive is, for example, a moisture-curable hot melt adhesive containing a urethane prepolymer. In general, a moisture-curable hot-melt adhesive can be polymerized by a chemical reaction to exhibit adhesive strength and the like. Urethane prepolymers with isocyanate groups are cured by reacting with moisture. Therefore, the moisture-curable hot-melt adhesive may be a urethane prepolymer alone, and contains an additive or the like used in the field of moisture-curable hot-melt adhesive in addition to the urethane prepolymer. It may be a thing.

Urethane prepolymer is, for example, a reaction product of a polyol and a polyisocyanate. The urethane prepolymer may be, for example, a urethane prepolymer having an isocyanate group. Urethane prepolymers having isocyanate groups are usually derived from polyols (compounds having two or more hydroxy groups in the molecule) and polyisocyanates (compounds having two or more isocyanate groups in the molecule). It has a polymer chain containing a derived structural unit and an isocyanate group. The isocyanate group may be bonded to the end of the polymerized chain.

The composition of the urethane prepolymer can be changed by changing the type / content of the polyol that gives the constituent unit derived from the polyol and the type / content of the polyisocyanate that gives the constituent unit derived from the polyisocyanate. .. Since the urethane bond is formed by the reaction between the polyol and the polyisocyanate, the polymerized chain of the urethane prepolymer has a urethane bond. By increasing the ratio of the equivalent of polyisocyanate to the equivalent of polyol, an isocyanate group can be introduced at the end of the polymerized chain.
[Adhesive pattern]

FIG. 2 is a plan view showing an example of the pattern of the bonded portion. In the figure, the expansion / contraction direction T1 of the elastic material 2 is set in the vertical direction of the paper surface. Further, for convenience of explanation, one elastic material 2 is shown, and the other elastic material 2 is omitted.

The adhesive portion 3A shown in FIG. 2 extends in a broken line shape with an extension axis P along the expansion / contraction direction T1 of the elastic material 2. More specifically, the adhesive portion 3A has a plurality of broken line portions 5. Each of the broken line portions 5 has a strip shape having a width of, for example, about 0.1 mm to 50 mm. The width of the broken line portion 5 may be 0.5 mm to 2.5 mm or 1.0 mm to 5.0 mm. The width of the broken line portion 5 is set in consideration of, for example, a range that can be applied with a dispenser. The bonded portion 3A has a zigzag shape as a whole by arranging these broken line portions 5 on the zigzag line L centered on the extending axis P.

In the line L, the positions of the groups of the broken line portions 5 adjacent to each other in the extending axis P direction are reversed with respect to the extending axis P. In the example of FIG. 2, the group of the broken line portion 5 is formed by the two broken line portions 5. One group 6A of the broken line portion 5 adjacent to each other in the extending axis P direction extends in the direction connecting the lower right of the paper surface and the upper left of the paper surface in FIG. The other group 6B of the broken line portion 5 adjacent to each other in the extending axis P direction extends in the direction connecting the upper right of the paper surface and the lower left of the paper surface in FIG.

Each of the broken line portions 5 on the line L intersects the extending axis P. The crossing angle θ between the broken line portion 5 and the extending axis P is, for example, about 5 ° to 85 °. The crossing angle θ between the broken line portion 5 and the extending axis P may be 20 ° to 80 ° or 40 ° to 70 °.
[Action effect]

As described above, in the joint structure 1, the adhesive portion 3A extends in a broken line shape and a zigzag shape with an extension axis P along the expansion / contraction direction of the

elastic materials

2 and 2 as a whole. Therefore, in the joint structure 1, as shown in FIG. 2, a region 10 in which the adhesive portion 3 and the non-adhesive portion 7 are alternately arranged in the expansion / contraction direction T1 of the elastic material 2 is formed along the extending axis P. Will be done. In the region 10, the non-adhesive portion 7 in which the adhesive portion 3 is not located serves as a stretch allowance for the stretchable material 2 with respect to the stretch direction T1, so that the stretchability of the stretchable material 2 can be sufficiently ensured.

Further, in the joint structure 1, each broken line portion 5 of the adhesive portion 3A intersects the extending axis P at an intersection angle θ. Therefore, the region 10 in which the adhesive portion 3A and the non-adhesive portion 7 are alternately arranged is formed in the direction T2 orthogonal to the expansion / contraction direction T1 of the elastic material 2 with a constant width R, and the bonding hardness of the elastic material 2 is formed. Can be sufficiently secured. In the example of FIG. 2, the width R of this region 10 corresponds to the distance in the direction T2 orthogonal to the expansion / contraction direction T1 between the

points

5a and 5a which are the peaks of the zigzag amplitude in the adhesive portion 3A.

Further, in the joint structure 1, since the adhesive portion 3A is formed into a broken line shape by the plurality of broken line portions 5, the amount of the adhesive used is reduced as compared with the case where the adhesive portion is continuously provided. There is a trade-off relationship between the reduction in the amount of adhesive used and the adhesive strength of the

elastic materials

2 and 2. When giving priority to reducing the amount of the adhesive used, for example, the zigzag pitch of the line L may be increased, or the length or width of each broken line portion 5 may be decreased. When giving priority to the adhesive strength of the

elastic materials

2 and 2, for example, the zigzag pitch of the line L may be reduced, or the length or width of each broken line portion 5 may be increased.
[Another example of adhesive pattern]

FIG. 3 is a plan view showing another example of the pattern of the bonded portion. The adhesive portion 3B shown in the figure is common to the adhesive portion 3A in that it has a broken line shape and a zigzag shape as a whole, but the configuration of each broken line portion 5 is different from that of the adhesive portion 3A. Specifically, in the adhesive portion 3B, each broken line portion 5 arranged on the zigzag line L extends in a direction intersecting (here, orthogonal to) the extending axis P.

The positions of the

broken line portions

5A and 5B adjacent to each other in the extending axis P direction are reversed with respect to the extending axis P. One of the broken line portions 5A adjacent to each other in the extending axis P direction extends from a position overlapping the extending axis P to one of the extending axes P (on the right side of the paper in FIG. 3). The other broken line portion 5B adjacent to the extending axis P extends from a position overlapping the extending axis P to the other side of the extending axis P (on the left side of the paper in FIG. 3).

The crossing angle θ between the

broken line portions

5A and 5B and the extending axis P (here, the crossing angle between the line L where the

broken line portions

5A and 5B are arranged and the extending axis P) θ is, for example, about 5 ° to 85 °. It has become. The crossing angle θ between the broken line portion 5 and the extending axis P may be 20 ° to 80 ° or 40 ° to 70 °.

The arrangement interval of the

broken line portions

5A and 5B in the extending axis P direction is not particularly limited, but in the example of FIG. 3, the

broken line portions

5A and 5B are the same as the width of the

broken line portions

5A and 5B in the extending axis P direction. They are arranged at intervals of degree. That is, between the

broken line portions

5A and 5B, the non-adhesive portion 7 exists with a width similar to the width in the extending axis P direction in the

broken line portions

5A and 5B.

Even in such an adhesive portion 3B, the same action as that of the adhesive portion 3A described above can be obtained, and while reducing the amount of the adhesive used, both the elasticity and the bonding strength of the elastic material 2 can be sufficiently secured. In the bonded portion 3B, the width R of the region 10 in which the bonded portion 3 and the non-bonded portion 7 are alternately arranged is the edge 5b on one side of the extending shaft P in the broken line portion 5A and the broken line portion 5B. It corresponds to the distance in the direction T2 orthogonal to the expansion / contraction direction T1 between the extending axis P and the other edge 5b.

FIG. 4 is a plan view showing another example of the pattern of the bonded portion. The adhesive portion 3C shown in the figure is different from the adhesive portion 3A in that it has a plurality of broken line-shaped and zigzag-shaped lines L. Specifically, the adhesive portion 3C has two lines L1 and L2 having a broken line shape and a zigzag shape. These two lines L1 and L2 are inverted with respect to the extending axis P.

In each of the lines L1 and L2, the zigzag repeating pitch is composed of one broken line portion 5. Each of the broken line portions 5 intersects the extending axis P, similarly to the adhesive portion 3A. The crossing angle θ between the broken line portion 5 and the extending axis P is, for example, about 5 ° to 85 °. The crossing angle θ between the broken line portion 5 and the extending axis P may be 20 ° to 80 ° or 40 ° to 70 °.

In each of the lines L1 and L2, the positions of the

broken line portions

5A and 5B adjacent to each other in the extending axis P direction are reversed with respect to the extending axis P. In the example of FIG. 4, one of the broken line portions 5A adjacent to each other in the extension axis P direction extends in the direction connecting the lower right of the paper surface and the upper left of the paper surface of FIG. The other broken line portion 5B adjacent to the extending axis P direction extends in the direction connecting the upper right of the paper surface and the lower left of the paper surface in FIG.

The

broken line portions

5A and 5B adjacent to each other in the extending axis P direction are separated from each other at a position corresponding to the peak of the zigzag amplitude. On the other hand, at the position of the extending axis P, the edge of the broken line portion 5A of one line L1 and the edge of the broken line portion 5B of the other line L2 are connected. Further, at the position of the extending axis P, the edge of the broken line portion 5B of one line L1 and the edge of the broken line portion 5A of the other line L2 are connected to each other.

From this, the

broken line portions

5A and 5B arranged in a zigzag manner on the two lines L1 and L2 have a pattern in which the broken line portions 5 forming a V shape are alternately inverted in the extending axis P direction. It can also be regarded as. In the bonded portion 3C, the width R of the region 10 in which the bonded portion 3 and the non-bonded portion 7 are alternately arranged is the

end points

5c and 5c in the direction T2 orthogonal to the expansion / contraction direction T1 in the V-shaped broken line portion 5. It corresponds to the distance between each other. Even in such an adhesive portion 3C, the same action as that of the adhesive portion 3A described above can be obtained, and both the elasticity and the bonding strength of the elastic material 2 can be sufficiently secured while reducing the amount of the adhesive used.

In FIGS. 2 to 4, the configuration in which the broken line portions 5 are arranged on the zigzag line L is illustrated, but the pattern of the adhesive portion is not limited to this. The line in which the broken line portion is arranged may have other shapes such as wavy, sinusoidal, and rectangular wavy. The shape of the broken line portion is not limited to the strip shape, and other shapes such as an arc shape, an L shape, an ellipse shape, and an oval shape may be adopted depending on the shape of the line.
[Effect confirmation test of adhesive part]

Next, the effect confirmation test of the bonded portion will be described. In this test, elastic materials were bonded to each other using the adhesive portions of each pattern according to Examples and Comparative Examples, and the elasticity and bonding strength of the obtained bonded structure were measured.
(Preparation of moisture-curable hot melt adhesive)

80 mass by weight of an amorphous polyester polyol (number of hydroxyl groups: 2, number average molecular weight: 2000) having an aromatic ring and containing dicarboxylic acids (adipic acid and isophthalic acid) and diols (ethylene glycol and neopentyl glycol) as main components. 4 parts by mass of an amorphous polyether polyol (bisphenol A / PO system, number of hydroxyl groups: 2, number average molecular weight: 360) having an aromatic ring, dicarboxylic acid (adipic acid) and diol (neopentyl glycol and 1, An amorphous polyester polyol (number of hydroxyl groups: 2, number average molecular weight: 5000) containing 4-butanediol as a main component and having no aromatic ring was dehydrated in advance by a vacuum dryer in 16 parts by mass. Diphenylmethane diisocyanate (manufactured by Toso Co., Ltd., trade name: Millionate MT, number of isocyanate groups: 2) has an equivalent ratio of isocyanate groups of polyisocyanate to hydroxy groups of polyol ((NCO) equivalent / (OH) equivalent) of 1.8. It was added to the reaction vessel so as to be, and mixed at 110 ° C. for 1 hour until uniform. This was defoamed and stirred at 110 ° C. for 1 hour to obtain a urethane prepolymer. The obtained urethane prepolymer was used as a moisture-curable hot melt adhesive.

In the preparation of each sample of Examples and Comparative Examples, a non-contact JET dispenser (manufactured by Musashi Engineering Co., Ltd .: IMAGE MASTER 350PC Smart) was used to expand and contract the moisture-curable hot melt adhesive melted at 100 ° C. in a predetermined pattern. It was applied on the sex fabric to form an adhesive portion. The outer diameter of the nozzle used for applying the adhesive was 18 G, and the application pressure was 150 kPa. Next, the same elastic fabric was placed on the formed adhesive portion and crimped at a temperature of 100 ° C. to obtain a crimped body. The pressure-bonded body was allowed to stand in a constant temperature bath at 23 ° C. and 50% RH for 3 days or more, and the adhesive was cured to obtain a bonded structure.

The elasticity was evaluated according to JIS-L1096 (method A) using the elongation rate of the bonded structure as an index. A tensile tester (manufactured by Shimadzu Corporation: EZ-test) was used for the evaluation. Each sample of the example and the comparative example was set in a tensile tester, each sample was stretched at a measurement temperature of 25 ° C. and a tensile speed of 300 mm / min, a load of 14.7 N was applied, and then the load was released.

FIG. 5 is a plan view showing the configuration of the sample in the elasticity evaluation. As shown in the figure, in each sample S of the example and the comparative example, the rectangular elastic cloth 11 was used, and the expansion / contraction direction T1 was set in the direction connecting the short sides. The length of the short side A of the elastic fabric 11 was 20 mm, and the length of the long side B was 150 mm. The length C of the expansion / contraction direction T1 of the region 12 forming the pattern of the bonded portion was 100 mm, and the width (length in the direction orthogonal to the expansion / contraction direction T1) D was 9 mm. The width D is a width corresponding to the width R of the region 10 in which the adhesive portions 3 and the non-adhesive portions 7 shown in FIGS. 2 to 4 are alternately arranged.

For each sample S, chuck portions 13 by a tensile tester were set at both end portions in the expansion / contraction direction T1. The length E of the chuck portion 13 in the expansion / contraction direction T1 was set to 25 mm. The distance between the chucks was set to 100 mm, which was equal to the length C in the expansion / contraction direction T1 of the region 10 forming the adhesive portion. The elongation rate (%) of each sample was calculated by the following formula.
Elongation rate (%) = (elongation amount (mm) / inter-chuck distance (mm) with a load of 14.7 N) × 100

The adhesive strength was evaluated using a tensile tester (manufactured by Shimadzu Corporation: EZ-Test EZ-SX). Each sample of Example and Comparative Example was set in a tensile tester, measured at a measurement temperature of 25 ° C. and a tensile speed of 100 mm / min based on a T-type peel strength test, and the measurement result was taken as the adhesive strength.

FIG. 6 is a diagram showing the evaluation test results of elasticity and adhesive strength in each pattern of the adhesive portion. As shown in the figure, Example 1 has the same pattern as the adhesive portion 3 shown in FIG. 2, and Example 2 has the same pattern as the adhesive portion 3 shown in FIG. Example 3 has the same pattern as the adhesive portion 3 shown in FIG. Comparative Example 1 is a pattern in which no adhesive portion is provided, and Comparative Example 2 is a pattern in which four continuous linear adhesive portions are provided apart from each other in the width D direction.

As shown in the figure, in Comparative Example 1, the elongation rate was 247%. That is, the original elongation rate of the elastic fabric 11 without the adhesive portion was 247%. In Comparative Example 2, the adhesive strength was 10 N / 9 mm and the elongation rate was 146%. On the other hand, in Example 1, the adhesive strength was 5N / 9 mm and the elongation rate was 233%, and in Example 2, the adhesive strength was 9N / 9 mm and the elongation rate was 200%. In Example 3, the adhesive strength was 5 N / 9 mm and the elongation rate was 209%.

From these results, in each of Examples 1 to 3, an adhesive strength of 5 N / 9 mm or more was obtained, which is comparable to Comparative Example 2 in which four continuous linear adhesive portions were provided. It can be seen that the adhesive strength is secured at the level. In particular, in Example 2, the adhesive strength is 9N / 9 mm, and it can be seen that almost the same adhesive strength as that of Comparative Example 2 is obtained.

Further, in Examples 1 to 3, an elongation rate of 200% or more was obtained in each case, and it can be seen that the elasticity was secured at a level comparable to that of Comparative Example 1 in which the adhesive portion was not provided. In particular, in Example 1, the elongation rate is 233%, and it can be seen that almost the same elongation rate as that of Comparative Example 1 is obtained. From the above results, it can be confirmed that by adopting the bonding structure of the present disclosure, both the elasticity and the bonding strength of the elastic material can be sufficiently secured.

FIG. 6 also shows the amounts of the moisture-curable hot melt adhesive used in Examples 1 to 3 and Comparative Example 2. In Comparative Example 2 in which four continuous linear adhesive portions were provided, the amount of the adhesive used was 0.17 g. On the other hand, in Examples 1 to 3 in which the broken line-shaped and zigzag-shaped adhesive portions were provided, the amounts of the adhesive used were 0.019 g, 0.065 g, and 0.060 g, respectively. Therefore, in Examples 1 to 3, it can be confirmed that the amount of the adhesive used is reduced by about 1/10 to 1/3 as compared with Comparative Example 2.

1 ... Joining structure, 2 ... Elastic material, 3 (3A to 3C) ... Adhesive part, 5 (5A, 5B) ... Broken line part, 6 ... Group of broken line part, P ... Extended axis, T1 ... Stretching direction.

Claims

It is a bonding structure in which elastic materials are bonded to each other by an adhesive portion having a predetermined pattern.
The adhesive portion extends in a broken line shape with an extending axis along the stretching direction of the stretchable material as a whole.
Each broken line portion of the adhesive portion is a joint structure that intersects the extending axis.
The joining structure according to claim 1, wherein in the adhesive portion, the positions of the groups of the broken lines adjacent to each other in the extending axis direction are reversed with respect to the extending axis.
The joining structure according to claim 1, wherein in the adhesive portion, the positions of the broken line portions adjacent to each other in the extending axis direction are reversed with respect to the extending axis.
The joining structure according to any one of claims 1 to 3, wherein each of the broken line portions of the adhesive portion extends in a direction orthogonal to the extending axis.
The bonding structure according to any one of claims 1 to 4, wherein the adhesive portion has a zigzag shape as a whole.
The bonding structure according to any one of claims 1 to 5, wherein the adhesive portion is composed of a hot melt adhesive.