JPH06182128A - Deodorizing electret material - Google Patents

Abstract

PURPOSE:To provide a deodorizing electret material having both of deodorizing properties and electret properties and having good charge stability. CONSTITUTION:The deodorizing electret material is obtained by adding at least one of hindered amic, nitrogen-containing hindered phenolic, metal salt- hindered phenolic, phenolic, sulfuric and phosphoric heat stabilizers to a synthetic org. polymer with volume resistivity of 10<13>OMEGA.cm or more within the range of 0.01-2% and characterized by that the surface charge density thereof is at least 1X10<-10> coulomb/cm<2>.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material having both deodorizing and electret properties which can be suitably used for filters, masks and the like.

[0002]

2. Description of the Related Art Various deodorizing electret materials have been proposed in which electret-processed fiber sheets and deodorizing agents such as activated carbon are superposed.

However, these materials have the drawbacks that when they are used for filters, for example, they have a large thickness, so the processability of the unit is poor and the ventilation resistance is high. Further, Japanese Patent Application Laid-Open No. 62-53719 proposes a filter material which is subjected to an electret treatment after deodorizing with a deodorant on the surface. However, this material has drawbacks that the volume resistivity of the surface becomes small because the deodorant is attached to the surface of the fiber, the electric charge obtained by the electret treatment is small, and the electric charge decays quickly.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a deodorizing electret material having a deodorizing property as well as a good electret property and good charge stability.

[0005]

The present invention has the following configuration.

That is, in a synthetic organic polymer having a volume resistivity of 10 ¹³ Ω · cm or more, a hindered amine type, a nitrogen-containing hindered phenol type, a metal salt hindered phenol type,
A deodorant component containing at least one of phenol-based, sulfur-based, and phosphorus-based heat stabilizers in the range of 0.01 to 2%, and a deodorant component containing a compound having an acid anhydride group is 0.1 to 10.
% And its surface charge density is 1 × 10 ^-10
A deodorizing electret material having a coulomb / cm ² or more.

[0007]

The concrete contents of the present invention will be described. That is, an organic polymer having a volume resistivity of 10 ¹³ Ω · cm or more, for example, polyolefin, polyester, fluorine resin, acrylic resin,
Deodorizing electret material containing 0.01 to 2% of a heat stabilizer as an electret stabilizer in a polyamide resin and 0.1 to 10% of a deodorant containing a compound having an acid anhydride group. Is.

A heat stabilizer is preferably used as the electret stabilizer, and the heat stabilizer is not particularly limited, but a hindered amine type, a nitrogen-containing hindered phenol type, a metal salt hindered phenol type is used. It is preferable to use a heat stabilizer selected from the group consisting of phenol type, sulfur type and phosphorus type. For example, in the case of hindered amines, poly [{(6
-(1,1,3,3-tetramethylbutyl) imino-
1,3,5-triazine 2,4-diyl} (2,2
6,6-Tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], dimethyl succinate-1- (2-
Hydroxyethyl) -4-hydroxy-2,2,6,6
-Tetramethylpiperidine polycondensate, 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4- Piperidyl).

In the case of nitrogen-containing hindered phenols, 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid or 1,3,5 -Tris (3,5-di-t-
Butyl-4-hydroxybenzyl) isocyanuric acid and the like.

Further, among the metal salts of hindered phenols, calcium salts of 3,5-di-t-butyl-4-hydroxy-benzyl-mono-ethyl-phosphonate,
3,5-di-t-butyl-4-hydroxy-benzyl-
There are nickel salts of mono-ethyl-phosphonate, magnesium salts of the same compounds, and the like.

Further, in the phenol type, 1, 3,
5-trimethyl-2,4,6-tris (3,5-di-t
-Butyl-4-hydroxybenzyl) benzene, pentaerythrityl-tetrakis [3-3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl- (3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionate and the like.

Further, as the sulfur type, there are distearyl thiodipropionate, dilauryl thiodipropionate and the like.

Further, phosphorus-based compounds include distearyl pentaerythritol diphosphate and the like.

As the deodorant, one containing a compound having an acid anhydride group is used. Examples of these include α, β-unsaturated dicarboxylic acid anhydride-based polymers, for example, a copolymer of maleic anhydride and styrene, and a Diels-based compound of α, β-unsaturated dicarboxylic acid anhydride and olefins. Alder reaction adducts and their derivatives, for example, an adduct of maleic anhydride and butadiene.

Further, the above-mentioned compound having an acid anhydride group may contain copper metal powder or a copper compound. Examples of the copper compound include inorganic acid salts, organic acid salts, complexes,
There are oxides. The content of the copper metal powder or the copper compound is 0.01 to the compound having an acid anhydride group.
200% is preferable.

Polymer materials containing the above additives are formed into fibers, films, woven fabrics, knitted fabrics, non-woven fabrics and papers. Such molding may be carried out by the conventionally known ordinary molding methods.

Thereafter, these materials are subjected to electretization treatment in a direct current high voltage to obtain an electret material having a high charge density. Such electretization processing can also be performed by a conventionally known method. In the present invention, the electret material has a surface charge density of 1 × 10 ⁻¹⁰
Coulomb / cm ² or more is generally shown. Also,
According to the knowledge of the present inventors, a sheet, such as a non-woven fabric, a film, a woven fabric, and a paper, which has been electretized has a surface charge density of 2 × 10 ⁻¹⁰ Coulomb / cm ² or more and an upper limit of 1 × 10. ^-8 Coulomb / cm ² is shown. In addition, the electric polarities of the front and back surfaces of the sheet are different.

As a form of the deodorizing electret material according to the present invention, a fiber has a large surface area and thus a large contact area with a malodorous component and excellent deodorizing performance, and particularly an average fiber diameter of 4 microns or less. Fine fibers are preferred. A melt blown nonwoven fabric is particularly preferable as the deodorizing electret material of the present invention because it is easy to make a fine fiber nonwoven fabric.

In order to exhibit the electret property while having the deodorizing property, the addition ratio of the electret stabilizer and the deodorant is important. The amount of electret stabilizer is 0.01
% Or more is required for electret property,
Further, if the amount is too large, there is no effect, and 2% or less is preferable. Further, 0.1% or more of the deodorant is necessary for deodorizing property, and if it is too much, it is not effective because it lowers the electret property.
The following are preferred.

[0020]

The electret material according to the present invention is
It has both electret and deodorant properties.
The electret property exhibits a remarkable effect due to the charges trapped in the electret stabilizer in the resin.

Further, these charges are due to environmental conditions, humidity,
Maintains a stable charge even when the temperature changes. The deodorizing property is considered to be effective when the compound having an acid anhydride group deactivates the malodorous component. Therefore, the electret material of the present invention is a filter, a mask, a packaging material,
It can be used for agricultural materials, wipers, various cover materials, hats, medical materials, etc.

In the present invention, the electret surface charge density is measured by the method shown in FIG.

That is, in the figure, the electret sample 3 is sandwiched between the electrodes 1 and 2, the induced charge is stored in the known capacitor 4, and the potential thereof is measured by the electrometer 5 and calculated from the following formula.

Surface charge density Q = C × V C: Known capacitor capacity (farad) V: Voltage (volt) Q: Surface charge density (coulomb / cm ² ) For deodorization, 1 g of a sample was put in a 300 ml container, 25
After substituting with air containing 0 ppm of ammonia gas, the airtightness is sealed and the concentration after 24 hours is measured and evaluated.

[0025]

EXAMPLES Hereinafter, further details will be described based on examples.

Example 1 3,5-di-t-butyl-4-hydroxy-benzyl-comprising polypropylene having a volume resistivity of 10 × 10 ¹⁶ Ω · cm and being a metal salt hindered phenol as an electret stabilizer. 0.2% of calcium salt of mono-ethyl-phosphonate and phenol-based pentaerythrityl-tetrakis [3-3,5-di-t-butyl-
4-hydroxyphenyl) propionate]
Metsuke 50 containing 3% of styrene-maleic anhydride copolymer (copolymerization composition = 75/25) as a deodorant.
A melt blown nonwoven fabric of g / m ² was produced.

This non-woven fabric was treated at a voltage of 30 KV for 30 seconds to be electretized. The surface charge of the non-woven fabric is 3.
At 5 × 10 ^-10 coulomb / cm ² , the polarities of the front and back surfaces were separated into positive and negative. The deodorizing rate of ammonia gas of the deodorizing meltblown nonwoven fabric was 98%. On the other hand, the general polypropylene meltblown nonwoven fabric used for comparison had a deodorization rate of 10%.

When this electretized non-woven fabric was used as a filter, the collection efficiency of 0.3 micron particles was 97% at a wind speed of 1.5 m / min. The general melt-blown nonwoven fabric used for comparison had a low collection efficiency of 40%.

Example 2 A melt-blown non-woven fabric made of polypropylene having a volume resistivity of 10 × 10 ¹⁶ Ω · cm and a basis weight of 20 g / m ² , and a hindered amine electret stabilizer as an electret stabilizer was used as poly-[{ (6-
(1,1,3,3-tetramethylbutyl) imino-1,
3,5-triazine 2,4-diyl} (2,2,6,6
-Tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] 0.1% and pentaerythrityl-tetrakis [phenol] 3-3,5-di-t-
0.1% of butyl-4-hydroxyphenyl) propionate] and 2% of a styrene-maleic anhydride copolymer (copolymerization composition = 50/50) as a deodorant.
A melt-blown nonwoven fabric having a basis weight of 20 g / m ² containing 0.1% copper sulfate and copper sulfate was produced. A voltage of 35 KV was applied to this nonwoven fabric for 30 seconds to form an electret.

Surface charge density is 5 × 10 ^-10 coulomb / c
At m ² , the polarities of the front and back surfaces were separated into positive and negative. The deodorizing rate of ammonia gas of this non-woven fabric was 100%, which was very good.

When a mask was made of this non-woven fabric and used in a hospital, it was comfortable because no bad odor such as urine or body odor in the hospital room was felt.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a method for measuring surface charge density.

[Explanation of symbols]

 1, 2: Electrode 3: Sample 4: Condenser 5: Electrometer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location A61L 9/01 B 8718-4C B01D 53/34 ZAB 116 A D06M 10/00

Claims (7)

[Claims] 1. A synthetic organic polymer having a volume resistivity of 10 ¹³ Ω · cm or more in a hindered amine-based, nitrogen-containing hindered phenol-based, metal salt hindered phenol-based, phenol-based, sulfur-based, phosphorus-based heat stabilizer At least one of them is contained in the range of 0.01 to 2%, and 0.1 to 10% of a deodorant component containing a compound having an acid anhydride group is contained, and the surface charge density thereof is 1 ×. A deodorizing electret material having a content of 10 ⁻¹⁰ coulomb / cm ² or more. 2. With respect to a compound having an acid anhydride group, 0.01
The deodorizing electret material according to claim 1, which comprises ˜200% of copper metal powder or copper compound. 3. A volume resistivity of 10 ¹⁵ as the synthetic organic polymer.
The deodorizing electret material according to claim 1, wherein an olefin polymer having an Ω · cm or more is used. 4. The deodorizing electret material according to claim 1, which is composed of fibers of a synthetic organic polymer. 5. The deodorizing electret material according to claim 4, which has an average fiber diameter of 4 microns or less. 6. The deodorizing electret material according to claim 1, wherein the deodorizing electret material is a non-woven fabric. 7. The deodorizing electret material according to claim 1, wherein the deodorizing electret material is a melt blown nonwoven fabric.