JP2570512Y2 - Complex - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a breathable composite. More specifically, the present invention relates to a gas-permeable composite having uniform air permeability in the width direction used for applications requiring uniform air permeability such as disposable warmers.

[0002]

2. Description of the Related Art In the composite formation of a gas permeable membrane, a method of bonding a point dry lamination, a heat lamination of partial fusion, an adhesive sheet provided with a ventilation portion alone, or an adhesive layer has been used. These are usually processed so as to uniformly bond the entire surface.

[0003]

However, when the composite is formed using a uniaxially stretched porous membrane having low air permeability (air permeability of 5000 sec / 100 cc or more), the porous membrane is
Due to the neck-in, the opening state of the film end is significantly deteriorated, and the gradient of the air permeability is easily generated in the film width direction due to this effect, and when the composite is formed by the conventional method, the air permeability differs depending on the position of the composite in the width direction, Therefore, there is a problem that the performance of the product differs depending on the part of the composite used.

[0004]

[Means for Solving the Problems] The present inventors have made intensive studies to solve the above problems, and as a result, have found that the ventilation portion adapted to the state of the air permeability in the width direction of the porous membrane at the time of compounding. It has been found that the above-mentioned problems can be solved by providing, and the present invention has been completed. In other words, the present invention combines a porous membrane (A) having different air permeability in the width direction with a gas permeable membrane (B) having a maximum air permeability of one-tenth or less of a minimum air permeability of (A). In addition, in the width direction of (A) and (B), compounding was performed by changing the area of the ventilation section so that the value obtained by dividing the air permeability by the area of the ventilation section was constant. This provides a good composite. Less than,
Although the present invention will be described in detail, the width direction referred to here refers to a direction perpendicular to the flow direction and the thickness direction during compound machining.

[0005] The porous membrane (A) having different permeability in the width direction used in the present invention is one in which the distribution curve of the permeability in the width direction has the same distribution curve in an arbitrary flow direction. Examples thereof include a sheet in which fine particles are dispersed in a thermoplastic resin, which is uniaxially or biaxially stretched.

[0006] The breathable membrane (B) used in the present invention is:
The maximum air permeability may be one-tenth or less of the minimum air permeability of (A), and examples thereof include paper, nonwoven fabric, and a perforated film obtained by perforating a thermoplastic resin film.
(B) naturally also has a variation in air permeability,
The maximum air permeability of (B) is 1/10 of the minimum air permeability of (A)
If it is below, the variation of the air permeability of (B) does not substantially cause a problem.

The composite method according to the present invention may be any method as long as (A) and (B) can be combined with an adhesive force according to the required function and the area of the ventilation portion of the composite can be changed in the width direction. Examples thereof include point dry lamination, thermal lamination using a permeable adhesive sheet, and thermal lamination in which a porous film and a permeable film are partially fused. As a method of changing the area of the ventilation section, in the case of point dry lamination, the area of the adhesive application section, when using a breathable adhesive sheet, how to provide the ventilation section of the sheet, in the case of partial fusion May be changed in the width direction as necessary.

[0008]

In the composite of the present invention, the variation in the air permeability in the width direction of (A) can be reduced by compounding, and a uniform air permeability with good uniformity in the width direction can be obtained. Products using any part of this composite have good uniformity in performance related to air permeability.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments, but the present invention is not limited thereto. In addition, the test method in this example was based on the following method. 1 air permeability JIS-P8117 (Gurley air permeability; 64
The number of seconds required for 100 ml of air to pass through an area of 5.16 mm ² (unit: sec / 100 cc). 2 Maximum pore size Measured by optical microscope observation. 3 Average dry coating weight The weight (i) of drying the film after applying the adhesive with hot air of 80 ° C. for 30 seconds, the weight (ii) of dissolving and removing the adhesive with a solvent and drying at the same temperature and time, and a sample. From the area (iii) of Equation (1).

[0010]

[Formula 1] (Average dry coating amount) = ((i)-(ii)) / (iii)

Example 1 a) Porous membrane (A) Minimum air permeability is 8000 sec / 1
A porous uniaxially stretched film having an air permeability gradient in the width direction at 00 cc as shown in Table 1 and FIG. 1 and comprising L-LDPE having a maximum pore diameter of 5 μm as a main component and a thickness of 50 μm. b) Air permeable membrane (B) Maximum air permeability is 2 sec / 100c
c, Nylon nonwoven fabric having a basis weight of 40 g / m ² . Using the above (A) and (B), with a pattern of an oblique lattice as shown in FIG. 5, a circular portion is a coating portion, and the center distance of the circular portion of this pattern is constant at 4 mm both vertically and horizontally, and the size of the circular portion Only the center radius is 1.1 mm as in 4 to 4 'in FIG.
By using a gravure roll having an opening ratio (area ratio of non-coated portion) as shown in Table 2 and FIG. The composite was formed by dry lamination using an adhesive as shown in FIG. At this time, the average dry coating amount of the adhesive at the center was 3.0 g / m ² . The air permeability of the composite is shown in Table 1 and FIG.

[0012]

FIG.

[0013]

FIG. 2

[0014]

FIG. 3

[0015]

FIG. 4

[0016]

FIG. 5

[0017]

[Table 1]

[0018]

[Table 2]

Comparative Example 1 The same porous film (A) and air permeable film (B) as in Example 1 were used, and the area ratio of the coated part and the design were the same as those of the gravure roll used in Example 1. Dry lamination was carried out in the same manner as in Example 1 by using a gravure roll having a constant width direction, to form a composite. The air permeability of the composite is shown in Table 1 and FIG.

[0020]

As is clear from the above embodiment, the porous membrane (A) having different air permeability in the width direction as in the present invention.
In the case of compounding by the conventional method as shown in Comparative Example 1, the difference in air permeability in the width direction remains in the composite as it is, but as in Example 1, the difference in air permeability in the width direction of (A) When the composite is formed by adjusting the area of the ventilation portion to match the difference in the air permeability, the difference in the air permeability in the width direction of the composite can be significantly reduced to one half or less of the porous membrane. .

[Brief description of the drawings]

FIG. 1 is a graph showing the air permeability distribution in the width direction of a porous membrane (A) used in Example 1 and Comparative Example 1 of the present invention.

FIG. 2 is a graph showing an area ratio of an opening (uncoated portion) of the gravure roll used in Example 1 of the present invention in a roll width direction.

FIG. 3 is a graph showing the air permeability distribution in the width direction of the composites produced in Example 1 and Comparative Example 1 of the present invention.

FIG. 4 is a diagram showing a configuration example of a complex.

FIG. 5 is a view showing an example of a pattern of an adhesive application section of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Breathable membrane (B) 2 Adhesive coating part 3 Porous membrane (A) 4, 4 'Adhesive coating part (or opening part depending on the case)

Claims (2)

(57) [Scope of request for utility model registration] 1. A porous membrane (A) having different air permeability in the width direction.
When the air permeable membrane (B) whose maximum air permeability is 1/10 or less of the minimum air permeability of (A) is combined, the area of the air permeable portion is changed in the width direction of (A) and (B). Composite with good uniform ventilation in the width direction. 2. The composite according to claim 1, wherein the porous membrane (A) is a uniaxially stretched film or sheet.