JPH04352875A - Polyolefin nonwoven sheet - Google Patents

Abstract

PURPOSE:To obtain the title sheet with excellent antistatic performance without declining in its waterproofness by incorporating a polyolefin nonwoven sheet with a specific antistatic agent and a water repellent consisting of fluorocarbon compound. CONSTITUTION:A polyolefin nonwoven sheet produced by flush or melt blow technique is, pref. put to corona discharge treatment, and incorporated or provided with (A) >=0.02wt.% of a textile finish of a compound of formula I (n is 1 or 2; R is 1-7C alkyl; M is Li, Na, K, H or ammonium ion; AO is CH2CH2O or of formula II; m is 1-10; (AO)m is CH2CH2O or alkylene oxide of formula III alone or such that CH2CH2O or said alkylene oxide are mutually bound in a brock or random fashion) (e.g. monoalkyl alkylene- or bisalkyl alkylene oxide phosphate salt and (B) >= 0.02wt.% of a water repellent consisting of a fluorocarbon compound (e.g fluoroalkylcarboxylic acid), thus obtaining the objective sheet with excellent waterproodness and antistatic nature.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet having waterproof properties and excellent antistatic properties. More specifically, the present invention relates to a polyolefin nonwoven sheet with excellent waterproof and antistatic properties that can be preferably used as sheets for protective clothing, windbreakers, raincoats, packaging materials, envelopes, sleeping bags, etc.

0002

BACKGROUND OF THE INVENTION Conventionally, various types of polyolefin nonwoven sheets have been known for use in the above-mentioned applications. For example, non-woven sheets obtained by pulling fibers spun based on the usual synthetic fiber spinning method at high speed with a high-speed air stream, non-woven sheets obtained by melt-blowing, and three-dimensional network fibers made of polyolefin fibrils by the so-called flash spinning method. Non-woven sheets made of Non-woven sheets produced by flash spinning are characterized by the fact that the constituent fibers are extremely fine and have a complex cross-sectional shape.
It is used for various purposes by taking advantage of its characteristics.

[0003] 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, the Special Publication No. 55-51068
The chemical formula in the publication is:

[Chemical 4] Mn R3-n PO4 (n is 1 or 2) If a fiber treatment agent is used that is a mixture of a compound where n is 1 and a compound where n is 2, waterproof property can be improved. It is disclosed that antistatic properties can be imparted without deterioration.

0004

[Problem to be solved by the invention] Japanese Patent Publication No. 55-5106
A fiber treatment agent made of a compound having the structure disclosed in Publication No. 8 can impart waterproofness and antistatic properties to a nonwoven sheet, but this fiber treatment agent has at least 0% by weight based on the fibers. It is necessary to use .1%. However, these fiber treatment agents on nonwoven sheets have an odor that Japanese people do not like, and from the viewpoint of odor and printing characteristics, it is desirable that the amount of adhesion be as small as possible, and the amount of adhesion of at least 0.1% is required. The above-mentioned fiber treatment agents have a problem in that their range of practical applications is limited.

[0005] The present inventors aimed to solve the above-mentioned problems of the conventionally known fiber treatment agents. ] is the molar ratio of the compound [II
A polyolefin nonwoven sheet characterized by containing 0.05% by weight or more of a fiber treatment agent, which is at least twice as much as the compound of [I], and 0.05% by weight or more of a water repellent consisting of a fluorocarbon compound.

[0006]

[Chemical formula 5] RM2 PO4 ... [II] R2 M
PO4 ... [III] (However, M is Li, N
a, K, H, or ammonium ion, and R is an alkyl group having 6 or 7 carbon atoms. ) has been found to have excellent waterproof and antistatic properties, and has already filed patent application No. 1-2797.
The application was filed as No. 65.

[0007] This polyolefin nonwoven sheet could reduce the amount of fiber treatment agent used, had low odor, had excellent printing properties, and had practically sufficient antistatic properties. However, this nonwoven sheet has the problem of yellowing over time, and if the fiber treatment agent is less than 0.05% by weight, the antistatic properties may become insufficient, and if the amount of the fiber treatment agent is less than 0.05% by weight, When this happens, waterproof properties tend to be impaired, and further improvements have been desired depending on the application.

[0008]

[Means for Solving the Problems] An object of the present invention is to provide a polyolefin nonwoven sheet having excellent waterproof properties and antistatic properties, and which uses a fiber treatment agent consisting of a compound represented by the following chemical formula [I]. This can be achieved by containing 0.02% by weight or more of water repellent and 0.02% by weight or more of a water repellent made of a fluorocarbon compound.

[0009]

embedded image (n is 1 or 2, R is an alkyl group having 1 to 7 carbon atoms, M is Li, Na, K, H, or ammonium ion, -AO- is -CH2 CH2 O -or

0010

[C7] , m is an integer from 1 to 10, -(AO)m　- is -CH2　CH2　O- or

0
011]

[Image Omitted] The alkylene oxides represented by the following formula are used singly or in blocks or randomly combined. )

001
2) The polyolefin nonwoven sheet of the present invention, which has not been given a fiber treatment agent and a water repellent, can be produced by a known method. For example, JP-A-61-160469 discloses an example of a method for producing a polypropylene continuous filament non-woven fabric, and JP-A-63-6107 discloses an example of a method for producing a polypropylene microfiber non-woven fabric by a melt-blowing method. .

Further, as examples of the flash spinning method, for example, Japanese Patent Publication No. 172073/1983 discloses an example of high-density polyethylene, and Japanese Patent Publication No. 192598/1987 discloses an example of polypropylene.

[0014] As an example of flash spinning, a polyolefin polymer is dissolved under high temperature and high pressure with a halogenated carbon such as trichlorofluoromethane or trichlorotrifluoroethane, a hydrocarbon such as methylene chloride, or a mixture thereof, and then rapidly spun. If a large pressure drop is applied, the solution will have a structure that appears to have undergone extremely fine phase separation. This liquid is discharged from a spinning nozzle to give orientation to the polymer and form three-dimensional network fibers. After shaking this onto a conveyor belt and forming it into a web, it is partially or surface-pressed using a roll (smooth roll, embossed roll, etc.) kept at room temperature or an appropriate temperature (below the melting point of polyolefin) or a felt calender to form a sheet. Make it. This nonwoven sheet is made of fibers with extremely fine and complex cross-sectional structures.

[0015] The basis weight of the above-mentioned nonwoven sheet is 30 to 20.
0 g/m2, preferably 40 to 100 g/m2. If it is smaller than 30 g/m2, sufficient waterproofness cannot be obtained. In addition, if it exceeds 200g/m2, flexibility will be lost,
It wrinkles or breaks easily during manufacturing, which is unfavorable from a quality standpoint.

The polyolefin nonwoven sheet of the present invention can be produced by adding a fiber treatment agent and a water repellent to the above-mentioned nonwoven sheet as described below. The fiber treatment agent of the present invention is a monoalkyl alkylene oxide phosphate salt having an alkyl group consisting of methyl, ethyl, propyl, butyl, hexyl, or heptyl (that is, various alkyl isomers from methyl to heptyl are also included); It consists of an alkyl alkylene oxide phosphate salt, and the molar ratio of both is from 3:1 to 1:3.
The ratio is usually approximately 1:1.

[0017] The alkyl group (R) has 8 or more carbon atoms, such as octyl cellosolve phosphate potassium, decyl cellosolve phosphate potassium, lauryl cellosolve phosphate potassium, octyl carbitol phosphate potassium, triethylene glycol monooctyl ether phosphate potassium In such cases, the water permeability of the polyolefin nonwoven sheet increases rapidly due to adhesion, impairing its waterproof properties. Also, alkylene oxide (AO
) is 10 or more, the hydrophilicity of the nonwoven sheet increases, and the antistatic and waterproof effect targeted by the present invention cannot be obtained. In this case, between polyethylene oxide alone and polypropylene alone, the waterproof property is less likely to be impaired when polypropylene oxide alone is used.

As for the C1 to C7 alkyl ether obtained by polymerizing polyethylene oxide and polypropylene oxide in a block or random manner, a phosphate salt having properties similar to those of polyethylene oxide alone can be obtained.

The water repellent made of a fluorocarbon compound used in the present invention includes fluoroalkylcarboxylic acids, perfluoroalkylcarboxylic acids, perfluoroalkylsulfonic acids and salts thereof (lithium, matrium,
potassium, etc.), monoperfluoroalkyl ethyl phosphate salts, fluorocarbons such as perfluoroalkylsulfonic acid diethanolamide, tetrafluoroethylene polymer, tetrafluoroethylene-hexafluoropropylene copolymer, trifluoromonochloroethylene polymer, vinyl fluoride copolymer, Fluoropolymers such as tetrafluoroethylene-perfluoroalkoxyethylene copolymer and tetrafluoroethylene-hexafluoropropylene copolymer can be mentioned.

[0020] These fluorocarbon compounds can be prepared in an aqueous solution,
It comes in the form of an emulsion or a dispersion, and can be applied in the usual way along with a fiber treatment agent. Specific examples include the dip-nip method, coating method, gravure roll method, kiss roll method, and spray method. The applied fiber treatment agent is dried and finished by hot air heating using a tenter or contact heating using a hot drum.

Furthermore, by performing corona discharge treatment 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 and water repellent can be facilitated. can. If corona treatment is not performed, add alcohol (ethanol,
1 to 10% by weight of acetone (propanol, etc.) or 0.05 to 1.0% by weight of a nonionic surfactant such as Triton x 100 (8 mole adduct of nonylphenyl ethylene oxide) to the treatment solution. By blending and using the fiber treatment agent and water repellent, it is possible to easily apply the fiber treatment agent and the water repellent.

[0022] At the same time, palmitic acid triglyceride,
Water repellents such as stearic acid triglyceride and dimethylpolysiloxane, anionic, cationic, nonionic, and amphoteric surfactants, and synthetic resin emulsions and latexes may be blended. Further, the fiber treatment agent and water repellent of the present invention may contain phosphates and other inorganic salts as long as the effects are not adversely affected.

[0023] The fiber treatment agent and the water repellent may be applied to the polyolefin nonwoven sheet in separate two-step processes, but it is preferable to apply them in one bath from the viewpoint of the process. When mixing fiber treatment agents and water repellent agents, there are issues such as their compatibility, ionicity, and pH. Taking these into consideration, a treatment solution with good solution stability is created and applied to polyolefin nonwoven sheets. .

Considering the conditions in which problems are unlikely to occur even when mixed with other compounds, ease of handling, and performance, the PH of the fiber treatment agent is determined by monoalkyl alkylene oxide phosphate salt and bis-alkyl alkylene oxide. The first and second equivalence points of the phosphate salt
It is necessary to adjust it to between 5 and 9, which is between the equivalence points. When applying a fiber treatment agent and a water repellent to a polyolefin nonwoven sheet that has undergone embossing or softening treatment for applications such as clothing, the treatment solution is less likely to form a film, and the amount of the fiber treatment agent attached can be reduced to zero. .5% by weight, it may be required to increase the water repellent to as much as 0.1% by weight. Usually, the amount of fiber treatment agent applied is 0.05 to 0.1% by weight, and the amount of water repellent is 0.05% to 0.1% by weight.
A nonwoven sheet having a sufficient antistatic effect can be obtained at about 0.03 to 0.05% by weight.

[0025] As described above, by using a fiber treatment agent made of a mono- and bis-alkyl alkylene oxide phosphate salt compound in a specific range and a water repellent made of a fluorocarbon compound, an antistatic effect can be achieved without impairing waterproof properties. can bring.

[0026]

EXAMPLES The present invention will be described 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 properties (half-life measurement method) Antistatic properties were evaluated by charging a test piece with corona discharge and then measuring the time (half-life) until the charged voltage attenuated by half. (JIS-L-1094) This measurement method is suitable for evaluating the static electricity attenuation 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.

[0027] Water resistance test Water resistance test was carried out using hydrostatic pressure according to 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 (mmH2 O) of the treated nonwoven sheet is 70% or more of the water pressure resistance (mmH2 O) of the untreated nonwoven sheet. ■Water repellency test (spray test) Measured using the waterproof test method for textile products (JIS-L-1092). However, since the nonwoven sheet is not substantially washed, it is evaluated in an unwashed state. In the water repellency test (spray test), even if the surface is wet, there is no water droplet wetting on the back side, and the water repellency is 70 or higher to pass.

■ Moisture permeability test Moisture permeability test method for textile products (JIS-L-1099) A
-1 method (calcium chloride method). This test method involves creating an air layer inside 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. absorb water vapor, measure the amount of permeation, and 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 of the treated nonwoven sheet (g/m2
．． It is sufficient if the moisture permeability (g/m2.day) of the untreated nonwoven sheet is maintained at 70% or more.

■ Yellowing test (accelerated dry heat test) After leaving the nonwoven sheet in a dry heat dryer (90°C) for 200 hours,
The nonwoven sheet is examined for yellowing. If there is no difference in visual judgment based on the untreated nonwoven sheet, it is determined that there is no change in yellowing. ■ Yellowing test (indoor storage test) A non-woven sheet was pasted on the wall in the laboratory and left for about 4 months (
After irradiation with sunlight (from the end of July to the end of November), the nonwoven sheet was examined for yellowing. If there is no difference in visual judgment based on the untreated nonwoven sheet, it is determined that there is no change in yellowing.

[0030] Odor determination: Cut 100 g of the nonwoven sheet into a size of about 5 x 5 cm, place it in a 1000 cc Erlenmeyer flask, and seal the narrow mouth with a silicone rubber stopper. In this state, put it in a constant temperature room at 24℃ for 24 hours.
After standing for a period of time, remove the silicone rubber stopper, smell the odor from the opening, and judge by the commonly used 6-level odor intensity display method (sensory test), and an odor intensity of 2 or less is considered to be a pass. (Table 1 shows the 6-level odor intensity display.)

[0031]

[Table 1]

[0032] In each of the Examples described below, the application of fiber treatment agents and water repellent agents and the preparation of samples for measurement were carried out in the following manner. The nonwoven sheet was immersed in a fiber treatment agent solution and a water repellent solution and nipped between rubber rolls having a hardness of 75±5 to remove excess solution from the surface of the nonwoven sheet. This wet non-woven sheet is air dried and then pre-specified 20±
The mixture was kept in a constant temperature room at 2° C. and 40±2% RH for 24 hours or more.

[0033]

[Examples 1 to 5 and Comparative Examples 1 to 5] Polyethylene polymer and solvent are discharged from a high temperature and high pressure condition to a low temperature and low pressure area from a nozzle, the solvent is flashed to form fibrillated reticular fibers, and then deposited in the shape of a wire mesh. Heat and pressure bonded using a calender roll at 130°C, area weight: 62g/m2, thickness: 0.
A 2 mm polyethylene nonwoven sheet was obtained. This sheet was subjected to corona discharge treatment and treated with 0.1% by weight aqueous solutions of various fiber treatment agents as shown in Table 1. All of these fiber treatment agents are mixtures of potassium mono- and bis-alkyl alkylene phosphates (approximately 1:1) shown in the table.
molar amount). A chlorotrifluoroethylene polymer dispersion water repellent was applied to the nonwoven sheet along with this fiber treatment agent, but since the surface of the nonwoven sheet had been previously subjected to corona discharge treatment, the treatment solution was applied to the nonwoven sheet sufficiently. I was able to have it granted. (The amount of the fiber treatment agent adhered was 0.1% by weight, and the amount of the water repellent was 0.05% by weight.) The results are shown in Table 2.

[0034]

[Table 2]

As shown in Table 2, the use of the fiber treatment agent and water repellent of the present invention showed good waterproof moisture permeability and antistatic properties, but the good water resistance of the nonwoven sheet is due to the presence of alkyl groups. It was found that when the number of carbon atoms increases beyond 8 (octyl), it is lost. Furthermore, it was found that the fiber treatment agent of the present invention poses no problem in terms of odor.

[0036]

Examples 6 to 9 and Comparative Example 6 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° C. to obtain a nonwoven sheet having a basis weight of 63 g/mm 2 and a thickness of 0.19 mm. The nonwoven sheet was previously subjected to a corona discharge treatment, and a fiber treatment agent consisting of potassium mono- and bisethyl cellosolve phosphate was applied to the nonwoven sheet in varying amounts. At the same time, a perfluoroalkyl acrylate compound was applied as a water repellent to the nonwoven sheet in an amount of 0.05% by weight. The results are shown in Table 3.

[0037]

[Table 3]

[0038] As shown in Table 3, it has been found that sufficient antistatic properties can be obtained by attaching the fiber treatment agent consisting of potassium mono-bisethyl cellosolve phosphate to the nonwoven sheet in an amount of 0.02% by weight or more. Ta.

[0039]

Examples 10 to 13 The basis weight of nonwoven sheets made of polypropylene produced by conventional melt spinning and melt blowing methods was 40 g/m2. The sheet was previously subjected to a corona discharge treatment, and then the effect of antistatic properties and water repellency was investigated when the metal (M) of the compound was changed in the fiber treatment.

The fiber treatment agent used was mono- and bisbutylcarbitol phosphate salt, the pH of the fiber treatment solution was adjusted between 5 and 7, and the adhesion amount was 0.1% by weight.
The nonwoven sheet was processed so that At the same time, a perfluoroalkyl acrylate compound was applied as a water repellent to the nonwoven sheet in an amount of 0.05% by weight. The results are shown in Table 4.

[0041]

[Table 4]

As shown in Table 4, it was found that the antistatic effect and waterproof property did not substantially change even if the metal (M) was changed.

[0043]

[Examples 14 to 19] The polyethylene nonwoven sheet obtained in Example 1 was coated with 0.1% by weight of a fiber treatment agent consisting of potassium mono- and bisbutylcellosolve phosphate and a water repellent consisting of a fluorocarbon compound shown in the table below. 0.05% by weight was added. The results are shown in Table 5.

[0044]

[Table 5]

As shown in Table 5, it was found that the waterproof effect did not change even if the water repellent made of a fluorocarbon compound was changed.

[0046]

[Examples 20 to 23 and Comparative Example 7] 0.05% by weight of a fiber treatment agent consisting of potassium mono- and bispropylene glycol tert-butyl ether phosphate and a tetrafluoroethylene polymer were added to the polypropylene nonwoven sheet obtained in Example 5. The amount of adhesion was varied. The results are shown in Table 6.

[0047]

[Table 6]

As shown in Table 6, 0.02% by weight or more of the tetrafluoroethylene polymer dispersion was applied to the nonwoven sheet while keeping the amount of the fiber treatment agent consisting of mono- and bispropylene glycol tert-butyl ether phosphate potassium constant. It was found that it was completely waterproof.

[0049]

[Examples 24 to 27 and Comparative Examples 8 to 9] A phosphate of butyl alcohol ethylene oxide adduct was added to the polypropylene nonwoven sheet obtained in Example 9 together with 0.05% by weight of a chlorotrifluoroethylene polymer dispersion water repellent. The effects of antistatic properties and water pressure resistance were investigated when 0.05% by weight of a fiber treatment agent with different moles of potassium ethylene oxide added was applied. The results are shown in Table 7.

[0050]

[Table 7]

As shown in Table 7, even when the number of moles of ethylene oxide added to butyl alcohol was increased from 1 to 10, good results were obtained in terms of spray water repellency, water pressure resistance, and antistatic properties.

[0052]

[Examples 28 to 33 and Comparative Example 10] The polyethylene nonwoven sheet obtained in Example 1 was treated with the following fiber treatment agent (PH5
~7) 0.5% by weight and 0.1 fluorocarbon compound
% by weight was given. The nonwoven sheet was subjected to a yellowing test. The results are shown in Table 8.

[0053]

[Table 8] As shown in Table 8, no yellowing was observed due to the combination of the fiber treatment agent of the present invention and fluorocarbon.

[0054]

Effects of the Invention The present invention is a polyolefin nonwoven sheet having excellent waterproof and antistatic properties as constructed as described above, and the above-mentioned problems have been solved.
As a result, it can be usefully used as a sheet for packaging materials, envelopes, protective clothing, windbreakers, raincoats, sleeping bags, etc.

Claims (1)

[Claims] 1. A polyolefin-free product characterized by containing 0.02% by weight or more of a fiber treatment agent made of a compound represented by the following chemical formula [I] and 0.02% by weight or more of a water repellent made of a fluorocarbon compound. knowledge sheet. [Formula 1] (n is 1 or 2, R is an alkyl group having 1 to 7 carbon atoms, M is Li, Na, K, H, or ammonium ion, -AO- is -CH2 CH2 O - or [Chemical 2], m is an integer of 1 to 10, -(AO)m - is -CH2CH2O- or an alkylene oxide represented by [Chemical 3] singly, or as a block or (It is a random combination.)