JPH0424286A - Nonwoven polyolefin sheet - Google Patents

Abstract

PURPOSE:To obtain the subject nonwoven sheet having excellent antistatic properties without impairing waterproofness by applying a specific phosphate salt compound to a polyolefin nonwoven sheet. CONSTITUTION:A polyolefinic polymer is formed into a three-dimensional netlike fiber by, e.g. a flash spinning method and the resultant nonwoven polyolefin sheet is presubjected to corona discharge treatment. A textile treating agent expressed by the formula (R is H or methyl; M is lithium, sodium, potassium, H or ammonium; n is 1 or 2), e.g. a blend of a monomethoxy lower alkyl phosphate salt with a bismethoxy lower alkyl phosphate salt at 1:1 molar ratio in an amount of >=0.01wt.% owf is applied to the resultant nonwoven polyolefin sheet to afford the objective nonwoven polyolefin sheet, having waterproofness and simultaneously excellent in antistatic properties.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sheet that is waterproof and has excellent antistatic properties. More specifically, the present invention relates to a nonwoven polyolefin sheet having excellent waterproof and antistatic properties that can be preferably used as a sheet for packaging materials, envelopes, protective clothing, windbreaker-1 raincoats, bedding, etc.

[Prior Art] Various types of sheets are conventionally known as nonwoven polyolefin sheets used for the above-mentioned purposes. For example, a non-woven sheet obtained by spinning fibers based on a conventional synthetic fiber spinning method and pulling them at high speed using a high-speed air stream, a non-woven sheet obtained by a melt-blowing method, and a polyolefin made into fibrillar three-dimensional network fibers by a so-called flash spinning method. A non-woven sheet made of carbon fibers is known. Nonwoven sheets produced by flash spinning are characterized by the fact that the constituent fibers are extremely fine and have a complicated cross-sectional shape, and these characteristics are used for various purposes.

When used in the above-mentioned applications, the nonwoven sheet is required to have waterproof properties and antistatic properties. In order to meet this demand, Japanese Patent Publication No. 55-51068 states:
If a fiber treatment agent which is a compound of the chemical formula MJs-aPOa (n is engineering or 2) and is a mixture of a compound with R of 1 and a compound with R of 2 in approximately equimolar amounts will impair waterproofness. It is disclosed that antistatic properties can be imparted without any

[Problem to be solved by the invention]

The structure disclosed in Japanese Patent Publication No. 55-51068 is used.
A fiber treatment agent consisting of a compound can impart waterproofness and antistatic properties to the nonwoven sheet, and the fiber treatment agent has a content of at least 0.1% by weight based on the fiber.

It is necessary to use it. However, when applying these fiber treatment agents to the nonwoven sheet 1, it is desired that the amount applied be as small as possible from the viewpoint of the back 4 and printing characteristics, and at least 0.
The above-mentioned fiber treatment agent, which requires an application amount of 1%, has a problem in that its range of practical applications is limited.

The present invention solves the old problems of the previously known fiber treatment agents that can impart both waterproofing and antistatic properties, and provides sufficient waterproofing even when applied in a very small amount. We have discovered a fiber treatment agent that can impart properties and antistatic properties to nonwoven sheets, and by applying this fiber treatment agent, we can achieve both waterproofness and antistatic properties, and improve product characteristics such as odor, especially oil-based offset ink printing. and U■ An object of the present invention is to provide a nonwoven polyolefin sheet that has excellent usability properties such as printing properties such that the drying speed of ink in offset printing is increased.

[Means to solve the problem]

The object of the present invention is achieved by a nonwoven polyolefin sheet characterized in that it contains a fiber treatment agent consisting of a compound represented by the following chemical formula in an amount of 0.01 or more based on the weight of the fibers.

R is hydrogen or a methyl group M is lithium, sodium, potassium, hydrogen or ammonium n is an integer of 1-2.

The nonwoven polyolefin sheet of the present invention can be manufactured by a known method. For example, JP-A No. 61-160469 discloses an example of a method for manufacturing polypropylene continuous filament nonwoven fabric, JP-A No. 63-6107 discloses an example of a method for manufacturing ultrafine polypropylene fibers, and JP-A No. 64-406 discloses an example of a method for manufacturing polypropylene microfibers.
Publication No. 18 discloses an example of a nonwoven sheet having a sheath-core structure, in which the core is made of polyethylene terephthalate or a copolymer thereof and the sheath is made of polyolefin such as polyethylene or polypropylene. Further, as an example of the flash spinning method, for example, Japanese Patent Publication No. 62-172073
The publication includes an example of high-density polyethylene,
No. 2598 discloses an example of polypropylene.

For example, a polyolefin polymer is dissolved under high temperature and pressure with halogenated carbon such as trichlorofluoromethane or trichlorotrifluoroethane, halogenated hydrocarbon such as methylene chloride, hydrocarbon such as cyclohexane, or a mixture thereof. After that, by applying a sudden pressure drop, the solution is given a structure that looks like it has undergone extremely fine phase separation.

This liquid material is discharged from a spinning nozzle to give orientation to the polymer and form three-dimensional network fibers (so-called flash spinning). After shaking this onto a conveyor belt and making it into a web, it is partially or completely crimped using a roll (smooth roll, embossed roll, etc.) kept at room temperature or an appropriate temperature (below the melting point of the polyolefin polymer) or a felt calendar. , form into a sheet.

This nonwoven sheet is made of fibers with extremely fine and complex cross sections.

The basis weight of the nonwoven sheet of the present invention is 30 to 200 g/
The amount is preferably 40 to 100 g/bo. If it is smaller than 30g/bo, sufficient waterproofness cannot be obtained. Moreover, if it is too thick, the flexibility will be impaired and it will wrinkle or break during manufacturing, which is unfavorable from a quality standpoint.

A fiber treatment agent consisting of a compound represented by the chemical formula is applied to the obtained nonwoven sheet.

When M is potassium, the fiber treatment agent of the present invention consists of potassium monomethoxy lower alkyl phosphate and potassium bismethoxy lower alkyl phosphate, the molar ratio of the two being between 3:1 and 1:3, and usually is approximately 1:1.

The fiber treatment agent of the present invention can be produced by a conventional method. For example, 1 mole of phosphorus pentoxide is added little by little to 3 moles of commercially available 3-methoxybutanol (manufactured by Daicel Hills) over time and stirred to produce mono- and bis-methoxybutyl phosphate. The resulting product is neutralized using caustic soda or caustic potash and adjusted to a predetermined pH. or,
Mono-bis-3-methyl-3-methoxybutyl phosphate sodium or potassium phosphate of the present invention can be produced in the same manner using 3-methyl-3-methoxybutanol (Tulfit 0; manufactured by Kuraray Co., Ltd.).

A conventional method can be used to apply the fiber treatment agent. Specific examples include dip-nip method, coating method, gravure roll method, kiss roll method, spray method, and the like. The applied fiber treatment agent is dried and finished by hot air heating using a tenter or contact heating using a hot drum. or,
By performing corona discharge treatment in advance before applying the fiber treatment agent, the wettability of the surface of the nonwoven sheet can be improved and the application of the fiber treatment agent can be facilitated.

If corona treatment is not performed, add approximately 1 to 10% by weight of alcohol (ethanol, propatool, etc.) or acetone to the fiber treatment agent aqueous solution.
0 (nonylphenylethylene oxide 8 mol adduct)
A nonionic surfactant such as 0.05 to 1.0% by weight may be added to the treatment liquid. At the same time, water repellents such as valmitic acid triglyceride, stearic acid triglyceride, and dimethylpolysiloxane, oil repellents such as perfluoroalkyl phosphate and perfluoropolyethylene, surfactants such as anionic, cationic, nonionic, and amphoteric surfactants, and synthetic resin emulsions. There is no problem even if it is mixed with other materials such as or latex.

The fiber treatment agent used in the present invention may also contain phosphates and other inorganic salts as long as the effects are not affected. The monobismethoxy lower alkyl phosphate salt of the compound represented by the chemical formula has a pH of 4 to 10 so that there is no problem even when mixed with such other compounds.
It is preferable to use it by adjusting it accordingly. p of fiber treatment agent solution
If the FI is too low, there will be problems such as it being difficult to achieve an anti-static effect and the area around the machine being susceptible to rust. In addition, if the pH is too high, skin damage etc. may occur during handling.

The fiber treatment agent of the present invention exhibits an antistatic effect when applied to the nonwoven sheet in an amount of 0.01% by weight or more. Generally, the fiber treatment agent is 1
．． Although it has been practiced to apply 0% by weight, such a large amount is not economical, and depending on the type of fiber treatment agent, there may be an odor problem, and it is also unfavorable in terms of printing characteristics. In this regard, the nonwoven sheet of the present invention has a very small amount of 0.01% by weight or more, which is much smaller than the amount of fiber that is conventionally thought to be applied in order to obtain the required waterproof and antistatic properties. By giving, you can achieve your goals. However, depending on the intended use, it may be added in an amount of 0.2 to 0.3% by weight to provide even better antistatic properties, and may be softened or embossed on the surface for use in clothing, etc. In this case, the treatment liquid is less likely to form a film, and it may be necessary to increase the amount of the fiber treatment agent applied to about 0.5% by weight.

〔Example〕

The present invention will be explained in detail with reference to Examples below. Prior to describing Examples, methods for measuring various physical properties of the nonwoven sheet of the present invention will be described.

・Antistatic property (half-life measurement method) After charging a test piece in a corona discharge field, this charging voltage is 1
The antistatic properties were evaluated by measuring the time (half-life) until decay to /2 (JIS-L-1094).

This measurement method is suitable for evaluating the static electricity decay characteristics of woven or knitted materials. A half-life of 60 seconds or less is acceptable, and a half-life of 10 seconds or less is more preferable.

・Water resistance test Measured using the hydrostatic pressure method of method A and method B of the waterproof test method for textile products (JIS-L-1092). In the water resistance test, it is sufficient that the water pressure resistance (wa H20) of the treated nonwoven sheet is 70% or more of the water pressure resistance (mIIHzO) of the untreated nonwoven sheet.

- Wood bark test (spray test) Measured using the waterproof test method for textile products (JIS-L-1092). In the wood bark test (spray test), although there was moisture on the surface, there was no water droplet moisture on the back surface, and the charcoal was 70 or higher with a charcoal resistance of 70 or higher.

・Moisture permeability test Method for testing moisture permeability of textile products (JIS-L-1099)
Method A-1 (calcium chloride method): This test method involves creating an air layer within a moisture-permeable cup, using the test piece as a boundary, drying the inside of the moisture-permeable cup with calcium chloride, and keeping the outside of the moisture-permeable cup in a humid condition. Water vapor is forcibly absorbed by the vapor pressure difference that occurs during this time, and the amount of permeation is measured to evaluate moisture permeability. Therefore, this test method is suitable for measuring moisture permeability under wearing conditions where the inside of clothing is humid, and can be applied to all textile materials including moisture-permeable waterproof materials. This moisture permeability is the moisture permeability Cg/rrf・day) of the treated nonwoven sheet.
70% of moisture permeability (g/rrf/day) of untreated nonwoven sheet
It's fine if you keep the above.

Application of the fiber treatment agent and preparation of measurement samples in each of the Examples described below were performed in the following manner.

The nonwoven sheet was immersed in a fiber treatment agent solution and nipped between rubber rolls having a hardness of 75±5 to remove excess solution from the surface of the nonwoven sheet. The wet nonwoven sheet was air dried, followed by drying at 105''C for 3 minutes. It was then conditioned in a prespecified thermostatic chamber at 20±2° C. and 40±2% RH for 24 hours or more.

1-3, ゛ 1-2 A nonwoven polyolefin sheet made of three-dimensional network fibers is used. That is, the polyethylene polymer and the solvent are discharged from a high temperature and high pressure condition to a low temperature and low pressure area through a nozzle, the solvent is flashed to form fibrillated reticular fibers, which are then deposited on a wire gauze and bonded under heat and pressure using a calendar roll at 130''C. A nonwoven polyethylene sheet with a basis weight of 63 g/rrr and a thickness of 0.2 m was obtained.This nonwoven sheet was subjected to a corona discharge treatment and treated with various fiber treatment agents as shown in Table 1.
It was treated with a 2% by weight aqueous solution. All of these fiber treatment agents are shown in Table-1.

The compound was a mixture of potassium mono-, bis-methoxy lower alkyl phosphates (1:1 molar ratio).

Each of these fiber treatment agents was applied to the nonwoven sheet in an amount of 0.05% by weight based on the weight of the fibers. Since the surface of the nonwoven sheet had been previously subjected to a corona discharge treatment, it was possible to easily attach it to the nonwoven sheet.

Table-1 All of the treated nonwoven sheets showed excellent antistatic properties.

4 to 7, *3 A polypropylene deposit nonwoven sheet consisting of three-dimensional network fibers was obtained in the same manner as in Example 1.

This sheet was partially crimped with an embossing roll at 155 DEG C. to obtain a nonwoven sheet having a basis weight of 69 g/bo and a thickness of 0.22 mm. The nonwoven sheet was previously subjected to a corona discharge treatment, and a fiber treatment agent consisting of mono-, bis-3-methoxybutylphosphate potassium was applied to the nonwoven sheet in varying amounts. The results are shown in Table-2.

Table 2 The fiber treatment agent according to the present invention is added to the nonwoven sheet in an amount of 0.01% by weight.
It can be seen that sufficient antistatic properties can be imparted by applying the above.

8 to 11, *4 A nonwoven polyolefin sheet made of polypropylene was obtained by ordinary melt spinning and melt blowing methods. Each of these nonwoven sheets had a basis weight of 40 g/rrr. The sheet was previously subjected to a corona discharge treatment, and then the effects of antistatic properties and water repellency were investigated when the metal (M) of the compound was changed as a fiber treatment agent.

The fiber treatment agent used was mono-, bis-3-methyl-3-methoxybutyl phosphate salt, and the hydrogen ion concentration (p)l) of the fiber treatment agent solution was between 6 and 7 (first and second equivalent points). The nonwoven sheet was treated so that the amount of fiber treatment agent deposited was 0.2% by weight.

It was found that the antistatic effect and waterproof property did not substantially change even if the metal (M) was changed.

A nonwoven sheet consisting of fibers with a sheath-core structure consisting of polyethylene in the sheath and polyethylene terephthalate in the core was obtained by a two-component melt spinning method. The basis weight of this non-woven sheet is 40
g/rd. A fiber treatment agent consisting of potassium mono-bis-3-methoxybutyl phosphate (0.5%) was added to the sheet.
% by weight and an aqueous solution containing 5.0% by weight of isopropyl alcohol, and was finished by drying. The amount of fiber treatment agent adhered to this nonwoven sheet was 0.1% by weight. Moreover, the half-life of Honestometer was 1.8 seconds, and the half-life of ice charcoal (spray method) was 90.

13-15, 5-8 The polyethylene nonwoven sheet obtained in Example 1 was subjected to antistatic processing using a fiber treatment agent consisting of 1 mole of potassium mono-3 methoxybutylphosphate and 1 mole of potassium bis-3 methoxybutylphosphate. For comparison, antistatic treatment was performed using a fiber treatment agent consisting of 1 mol of potassium monobutyl phosphate and 1 mol of potassium dibutyl phosphate, and the coating amount was changed so that the honest meter half-life was 60 seconds or less. I created a sheet. The odor of the treated sheets and the drying properties of the printing ink were compared.

Table 3 Comparison of odor is shown in Examples 13, 14, 15 and Comparative Example 5
゜100g of sample of 6.7.8 is about 5C1l each
Cut into pieces of 5CI size, place in a 500d Erlenmeyer flask, and seal the narrow neck with a silicone rubber stopper. After leaving this condition in a constant temperature room at 24°C for 24 hours, remove the silicone rubber plug, smell the odor from the opening, and judge it using the commonly used 6-level odor intensity display method. did.

Table 46-level odor intensity display method Regarding the drying time of ink, see the drying time for oil-based offset ink (
Impermeable ink: Compared to the ingredients of ordinary oil-based offset inks, the pigments, resins, drying oils, auxiliary agents, metal soaps, etc. remain unchanged, while the petroleum-based high boiling point solvent is kept to about 1%. ) printed on the entire surface of 15cm x 20cm,
Leave it in a room at 24°C. Press the Sellotape against the printed surface every hour and check the time until the ink no longer transfers to the Sellotape, which is considered the drying time. 1-4
A case where the drying time was within an hour was judged as a pass (◯), a time of 5 to 8 hours was judged as a semi-pass (Δ), and a case of 8 hours or more was judged as a failure (x).

It can be seen that the 3 methoxybutyl phosphate salts of the present invention are useful in odor and ink drying properties.

〔Effect of the invention〕

The present invention allows the non-woven polyolefin sheet of the present invention to contain a fiber treatment agent having the following chemical formula in a weight percent of the fibers of o, oi or more. It can have antistatic properties. In addition, it was confirmed through actual experiments that this fiber treatment agent has little odor and does not cause any problems in printability.

R is hydrogen or methyl group M is lithium, sodium, is ammonium n is an integer of 1 to 2.

potassium, Hydrogen Mata

Claims (1)

[Scope of Claims] A nonwoven polyolefin sheet characterized by containing a fiber treatment agent consisting of a compound represented by the following chemical formula at 0.01% or more by weight of the fiber ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ R is hydrogen or methyl group M is lithium, sodium, potassium, hydrogen or ammonium; n is an integer of 1 to 2;