JPS62227932A - Moisture-permeable aromatic film - Google Patents

Abstract

PURPOSE:To obtain a film which can not be permeated by liquid water but can be permeated by water vapor and which can prevent malodor and can emit pleasant odor, by stretching a sheet comprising polyethylene and an inorganic filler impregnated with a perfume. CONSTITUTION:A film obtained by molding a mixture of polyethylene and an inorganic filler impregnated with a perfume into a film and stretching this film. In order to further improve the moisture permeability, stretchability, flexibility, etc. useful for, especially, a back film of a disposable diaper, a mixture containing high-pressure process low-density polyethylene (MI >=10) and/or ethylene/alpha-olefin copolymer (crystallinity <30%) in addition to the above mentioned components is formed into a sheet and this sheet is stretched. In this way, a film having necessary properties can be obtained inexpensively. As the inorganic filler added, a porous one is particularly desirable.

Description

[Detailed Description of the Invention] 3゜First Origin and Third Description of the Invention (Field of Industrial Application) The present invention relates to a moisture-permeable film, and more specifically, the present invention relates to a moisture-permeable film that does not allow liquid water to pass through it, but allows air to pass through the water. ,IL1 Prevents bad odors1
The present invention relates to a moisture-permeable fragrance film that emits a pleasant fragrance.

(Prior Art) Conventionally, disposable diapers have been rapidly increasing as diapers used for infants, sick people, etc. The performance required of the backing film used in such diapers is not only water impermeability as a function of the diaper, but also water vapor permeability, that is, moisture permeability, in order to prevent skin irritation by 11x. It is desired to have the following.

(Problem to be solved by the invention) Conventionally, a water-impermeable polyethylene film has often been used as the backing film used in the above diapers, but since it is not moisture permeable, even if you sweat, it will not absorb moisture. The water is not evaporated, causing diaper rash.

In order to solve these problems, various moisture permeable films have been proposed. Conventional moisture permeable films include, for example, those that are perforated by electric discharge, those that are obtained by removing fillers after mixing them, those that are obtained by stretching crystalline plastics, and those that are obtained by stretching crystalline plastics. There are moisture-permeable films obtained by stretching a blend of resins and stretching a plastic filled with an inorganic substance.

Conventional moisture permeable films such as those described in 1- are porous and are therefore water vapor permeable, but because of their porous nature, there is a problem in that odor is diffused into the surroundings along with water vapor.

A common way to solve this problem is to add fragrance! However, it is possible to mask odors by applying fragrance to a moisture-permeable film such as the one described above from the outside.
However, the disadvantage is that the effect is short-lived and not permanent, and the fragrance is lost during the distribution process of the product. One way to solve these drawbacks is to incorporate fragrance into the film, but since polyethylene is usually molded at a high temperature of 150 to 220°C, it has a relatively low melting point. It is almost impossible to melt-knead certain fragrances into polyethylene.

As a result of intensive research in order to solve the conventional drawbacks as described in the present invention, when preparing a moisture permeable film made of polyethylene and an inorganic filler, preferably a porous inorganic filler is used as the inorganic filler. However, when the fragrance is preliminarily mixed into the inorganic filler of the IL tube, the fragrance can be easily melt-kneaded into the polyethylene, and the resulting moisture-permeable film has a permanent fragrance release property. Did you know that tree 3? ! Completed step 1.

(Means for Solving the Problems) That is, the present invention provides a moisture-permeable film formed by stretching a sheet-like material made of polyethylene and an inorganic filler in at least one axis direction. This is a moisture-permeable fragrance film that is characterized by:

Next, the present invention will be explained in more detail.

The polyethylene used as a base material in the present invention includes ethylene alone or ethylene and 1-butene, l-pentene, l-
It is obtained by polymerizing or copolymerizing octene and 4-methylpentene-xl with an α-olefin under low pressure, and linear low-density polyethylene having a density in the range of 0.90 to 0.94 is preferable.

Examples of inorganic fillers added to the above polyethylene include calcium carbonate, magnesium carbonate, calcium sulfate, calcium sulfite, magnesium sulfate, calcium phosphate, basic magnesium carbonate, sodium chloride,
Wtm sodium, barium carbonate, barium sulfate, aluminum oxide, zinc oxide, magnesium hydroxide, calcium oxide, magnesium oxide, strontium oxide, barium oxide, titanium oxide, alumina, mica, silicic acid,
Examples include kaolin, talc, clay, shirasu, diatomaceous powder, glass powder, zeolite, metal powder, etc., and these may be used alone or in a mixture of two or more. Among these fillers, porous fillers are particularly preferred.

The particle size of such inorganic fillers is preferably 20 #i, m or less in powder form, and considering the dispersibility in the resin, these inorganic fillers are pre-mixed with fatty acids or metallic soaps of fatty acids. It is also preferable to add a dispersant such as or use a surface treated with such a dispersant. In addition, if there is a risk that the film may foam due to adsorbed moisture during molding, we can dehydrate it by using an alkaline earth metal oxide as a component of the inorganic filler to prevent foaming.
can do.

The inorganic filler as described in 1- below is the polyethylene 100 tons! 11,1 per part ii in the range of 50 to 300 parts by weight
Use when If the amount of inorganic filler used is less than 50 parts, a moisture permeable film with a moisture permeability of 1 minute cannot be obtained, while if the amount used is more than 3 parts, Since the physical properties of the film 11 of the resulting moisture permeable film will be insufficient, Ilf is not acceptable.

The fragrances used in the present invention and which mainly characterize the present invention include natural and synthetic fragrances conventionally used in various fields, such as vanillin, jasmine, lavender, strawberry, heliflower, rose, and amyl. Any of a variety of scented fragrances can be used, such as acetate. Any of these fragrances 1 can be obtained and used from the market. Such fragrances are used by being impregnated in the above-mentioned inorganic filler in advance.

As a method for impregnating the fragrance into the inorganic filler, in the case of a liquid fragrance, it is also possible to spray it onto the surface of the porous inorganic filler and make it adsorbed, but it is preferable to impregnate the fragrance into the inorganic filler. is dissolved in an organic solvent with a relatively low concentration point, or emulsified or dispersed in water, and the above-mentioned porous inorganic filler is added thereto to impregnate it, or such a solution or emulsion is mixed with an inorganic filler. A preferred method is to impregnate the material by spraying it on the surface of the material, and then dry and remove the organic solvent and moisture.

Impregnation of Kana 4 into inorganic fillers! 1 may be in any range, but is generally preferably in the range of about 0.01 to 5 parts by weight per 100 parts by weight of the inorganic filler.

The moisture-permeable fragrance film of the present invention can be obtained by adding an inorganic filler impregnated with fragrance 1 to polyethylene as described above, forming it into a film, and stretching it, which is useful as a backing film for disposable diapers. In order to further improve the moisture permeability, stretchability, flexibility, etc., in addition to the above components, the following specific components are added: high 1E process low density polyethylene with a melt index of 10 or more and/or '+ conversion jM less than 30% ethylene-α
- It has been found that by adding an olefin copolymer and forming the film into a sheet and stretching it, a moisture permeable fragrance film having the required performance such as excellent moisture permeability and flexibility can be obtained at low cost at a low stretching rate.

High-pressure low-density polyethylene with a melt index of 10 or more is polyethylene produced by Togane using a high-pressure method and has a melt index of 10 or more when measured at 190°C under a load of 2t80g in accordance with ASTM-D-1238-[15. be. High-pressure low-density polyethylene having a melt index of less than 10 was not evenly effective in improving drawing suitability.

In addition, ethylene-α-olefin copolymers with a crystallinity of less than 30% include ethylene, propylene, l-butene, 3
-Methylbutene-1, ■-hexeno, 3-methylpentene-1,4-methylpentene-11 is a copolymer of two or more alpha olefins, and its crystallinity is less than 30%. So, the density is 0.85 to 0.90
It is within the range of . Its addition significantly improves flexibility and extensibility.

The following high-pressure low-density polyethylene with a melt index of 10 or more and the ethylene-α-olefin copolymer with a crystallinity of less than 30% can be used alone or in a mixture, and in either case, lO~100 per 100-111 parts of polyethylene? ,
't: It is preferable to use it within the range of parts. Use t, 1
However, if it is less than 10 times F1, the stretching suitability will be affected.
- minutes, the flexibility is insufficient, and the stretching ratio is 1.
II) It is not preferable because a moisture permeable film having high moisture permeability in minutes cannot be produced. On the other hand, if i- exceeds 100°j, even if stretched, the moisture permeability will not be in the direction of i', and the physical properties of the film will not be in the direction of -2.

The moisture permeable film of the present invention has two components as essential components, but also contains various other elliptical agents such as pigments, lubricants, dispersants, stabilizers, flame retardants, anti-static agents, plasticizers, etc. It goes without saying that it can be included as desired.

The manufacturing method of the moisture-permeable scent-releasing film of the present invention is not particularly limited, except that a sheet-like material made of the above-mentioned components is stretched in at least one axis direction. The mixture may be mixed and formed into a sheet by calender molding, extrusion molding, etc. according to the method. In the extrusion molding, ordinary film and sheet molding equipment and molding methods such as the inflation method and the T-die method can be used. In particular, when forming the above ingredients into a sheet, a masterbatch method is preferred, in which an inorganic filler impregnated with a fragrance and a part of the resin component are melt-kneaded to create a masterbatch, and this is diluted with an unadded resin component. In particular, an inorganic filler impregnated with a fragrance is melt-kneaded with a high-pressure low-density polyethylene and/or an ethylene-α-olefin copolymer using a twin-screw kneader, pan/S mixer, etc. to form a mixture around the inorganic filler. Coated with high-pressure low-density polyethylene and/or ethylene-α-olefin copolymer f
It is preferable to use the film at a low stretching ratio of f, since it is possible to obtain a moisture permeable film with better permanent fragrance release properties at a low stretching ratio.

The sheet-like material obtained as described above may be stretched in at least one direction, and for example, any stretching method such as machine roll stretching, tubular stretching, simultaneous biaxial stretching, or sequential biaxial stretching may be used. By stretching the sheet I-shaped material in this way, physically fine gaps are efficiently created between the resin and the inorganic filler impregnated with the fragrance contained in the sheet-shaped material. The gaps allow perfume to escape and water vapor to pass through, but liquid water is impermeable. The stretching ratio (l) is preferably about 120 to 500%, and the thickness of the obtained moisture-permeable fragrance film is about 110-10
Approximately 0p is suitable.

(Effects of Effects) According to the present invention as described in 1 above, it has excellent required performance as a back sheet for disposable diapers such as moisture permeability and flexibility,
(2) A moisture-permeable fragrance film that can permanently mask the odor emitted with water vapor for a long period of time with only $1 of fragrance can be easily provided at an extremely low cost.

Next, the present invention will be explained in more detail with reference to Examples. In addition, unless otherwise specified, the terms "part" and "%" in the text refer to "Gyokusei no" ((junior)).

Example 1 A cleansing fragrance (rose) was dissolved in ethanol to a concentration of 10 parts, 10 parts of this solution was absorbed into 100 parts of porous calcium carbonate (average particle size 4 microns), and the alcohol content was then completely removed. evaporated to.

Low density polyethylene (MI=30. d=0.915
) and 130 parts of the above fragrance-impregnated calcium carbonate were kneaded in a twin-screw kneader and then granulated. 100 parts of ethylene-1-butene copolymer (MI = 2.0, d = 0.920), which is a linear low density polyethylene, was added to 165n of this granulated material, and the mixture was heated at 60°C using a T-die film forming machine. I threw the sheet away. This was uniaxially stretched in the longitudinal direction at 50°C, and then stretched at 35°C.
The moisture-permeable fragrance film of the present invention having a thickness of 11 tons was prepared.

Example 2 A fragrance that gives a feeling of cleanliness (lavender) is added to ethanol.
10 parts of this solution was absorbed into 100 parts of porous calcium carbonate (average particle size 2.3 microns), and then the alcohol content was completely evaporated.

Ethylene-1-butene copolymer (MI = 2.0, d
= 0.920) 100 parts, 25 parts of ethylene-propylene copolymer (MI = 3.2, d = 0.88), 130 parts of the above fragrance-impregnated calcium carbonate and 10 parts of calcium oxide were kneaded in a twin-screw kneader. , granulated. This granulated product is manufactured by T-die film F! A sheet of 8071 m was obtained by the machine. This was uniaxially stretched in the longitudinal direction at 70°C using a -axial stretching machine to form a finished moisture-permeable fragrance film with a thickness of 40°C (11/Example 3 Flower!triwo'j) Perfume (Heli No. 1 Rope) was dissolved in acetone to a concentration of 5 parts, porous barium sulfate was dispersed in this solution, stirred for 3 hours, filtered and dried.

Ethylene-1-butene copolymer (MI=2.0,
d=0.920) 100 parts, high pressure low density polyethylene (MI=30, d=0.915) 35 parts, ethylene-propylene copolymer (MI=3.2, d=0
．． 88) After kneading 35 balls of dark part and 150 parts of the above perfume-impregnated barium sulfate with 44 parts of twin-screw B, the mixture was granulated. A sheet of 70 parts m was obtained from this granulated material using a T-die film forming machine. This was uniaxially stretched in the longitudinal direction at 50° C. using a -axial stretching machine to obtain a moisture-permeable fragrance film of the present invention having a thickness of 40 μLm.

Table 1 shows the results of measuring the physical properties 4ttt of the moisture-permeable scented films of Examples described in 1 to 4 according to the following criteria.

(I) Moisture permeability (g/m'24hrs,) ;jls Z
Measurement was performed at 40° C. and 90% RH in accordance with -0208.

(II) Breaking strength (g/15mm, length/width); 1
It was cut to 115 mts and tested for 300 m using a tensile tester.
The strength at break was determined by pulling at a speed of +m/win.

(m) Elongation at break (%, length/width); The elongation at break was determined in the same manner as the breaking strength.

(IT) Flexibility; measured as a sense of touch by hand.

1 (Good) -- 5 (Poor) (V) Odor release property: The film was left to stand for 6 months after formation, and the odor release property after 6 months was examined by a sensory test. did.

l　　　　Acupoint Yu l1m1'VV

Claims (3)

[Claims] (1) A moisture-permeable fragrance film formed by stretching a sheet-like material made of polyethylene and an inorganic filler in at least one direction, characterized in that the inorganic filler is impregnated with a fragrance. (2) Claim No. 1 in which the inorganic filler is porous
) The moisture-permeable fragrance film described in item 1. (3) The moisture-permeable fragrance film according to claim (1), wherein the inorganic filler impregnated with a fragrance is melt-kneaded in advance with polyethylene or an ethylene-α-olefin copolymer.