JPH02127550A - Production of non-woven fabric containing fine particle - Google Patents

Abstract

PURPOSE:To obtain the aimed non-woven fabric containing fine particles uniformly dispersed in web and sufficiently exhibited in characteristics of sterilizing properties, deordorizing properties, etc. by drawing melted material of a thermoplastic polymer with high-pressure jet stream accompanying fine particles in fiber web formation. CONSTITUTION:A thermoplastic polymer or thermoplastic polymer containing additives is heat melted and discharged from a spinning orifice and the discharged and melted material is drawn with high-pressure jet stream accompanying fine particles to form fiber stream and the fiber stream is caught on the catching face to prepare a fiber web containing at least 30wt.% fine particles and at least one surface side of the above-mentioned fiber web is subjected to densifying treatment to provide the aimed non-woven fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application] The present invention relates to a method for producing a nonwoven fabric containing fine powder particles. Specifically, the present invention relates to a method for producing a nonwoven fabric that retains all powder particles and has properties such as sterilization, deodorization, aroma, liquid absorption, moisture absorption, demon prevention, and seedling-raising properties.

[Conventional technology]

Conventionally, nonwoven fabrics containing fine particles have been used as canes, and methods for making nonwoven fabrics using fibers containing specific fine particles have been described, for example, in Japanese Patent Application Laid-Open No. 60-81360, %-Sho 62-69.
No. 53, Japanese Patent Application Laid-open No. 62-6954, etc. propose to make a nonwoven fabric from fibers carrying a specific substance to impart 4M, thermal properties, and deodorizing properties. In addition, as a method for making Kufu cloth containing specific fine powder particles, for example, powdered medicinal stones are entangled in advance using a NEP forming machine to form a spherical fibrillated mass that is included in the entangled fibers. Japanese Patent Application Laid-Open No. 56-91053 discloses a method for producing a sheet-like product in which a non-woven cube is sealed and mechanically bonded when forming a non-woven web, in which one side of a fibrous web containing heat-fusible fibers is heat-sealed and the other side is sealed. The surface is made of a non-M fabric with fluff left behind, the powder is placed on the fluffed surface, the fluffed side of another non-woven fabric is placed on top of that, heat treated, and pressed to integrate the powder. A manufacturing method for non-woven fabric is disclosed in Japanese Patent Application Laid-Open No. 60-52661, and a method for incorporating powder between sheets of 2N non-woven fabric is disclosed in 1982-13.
No. 3171, f# by the melt blown method
! When dispersing valve fibers and superabsorbent substances into the fiber web during the production of textile fibers, the additive substance is turbulently merged with the fiber #I stream, which is being conveyed by the secondary air stream, using the secondary air stream. That is, Japanese Patent Application Laid-Open No. 54-59466,
JP-A-60-231853, JP-A-61-758
This is proposed in Publication No. 60, etc. ) [Problems to be Solved by the Invention] In the conventional manufacturing method of a nonwoven fabric containing fine powder particles, it is difficult to support the fine powder particles in the web fiber space, and a large amount of shedding occurs, and uniform dispersibility cannot be obtained. Therefore, the characteristics of the fine powder particles cannot be fully exhibited effectively.

Therefore, in order to identify fine particles within a nonwoven fabric, methods such as fixing the particles by making the fibers that make up the nonwoven fabric adhesive, fixing them with a binder, and further adding methods to the fibers have been used. There is. However, a fine powder coated with a single polymer coating cannot act instantly and cannot effectively exhibit its properties. In addition, when manufacturing a fiber web using the melt-blown method, a method in which additives are mixed in a turbulent state with a secondary air stream into the fiber stream being conveyed by a secondary air stream, produces a fiber web with good homogeneity. It is difficult to make, and it is difficult to uniformly disperse fine powder particles.

In the present invention, fine powder particles are uniformly dispersed in the nonwoven fabric fiber space,
To obtain a nonwoven fabric with less shedding.

In addition, almost no particulate matter in the nonwoven fabric falls off.

It is an object of the present invention to provide a method for producing a nonwoven fabric structure that can effectively exhibit the characteristics of fine powder particles.

[Failure to solve the problem]

The invention is to heat and melt a thermoplastic monomer or a thermoplastic polymer containing an additive, to discharge it from a spinning orifice, and to transform the discharged melt into a traction fiber stream with a high-pressure jet gas stream accompanied by fine particles, collecting the fiber stream on a collecting surface to produce a fibrous web containing at least 301 parts of fine powder;
This is a method for producing a nonwoven fabric containing fine powder, characterized in that at least one side of the fiber cube is subjected to a densification treatment.

Further, the present invention heats and melts a thermoplastic polymer or a thermoplastic polymer containing additive gold, discharges it from a spinning orifice, draws the discharged melt into a fiber stream with a high-pressure jet gas stream, and directs the fiber stream to a collecting surface. (a) A high-pressure injected gas flow that does not contain fine powder particles or is accompanied by fine powder particles is used to pull the fibers into a stream, and the fine powder particles are collected from 0 to
A fiber web 1 containing less than 30% by weight is formed, (b) it is drawn into a traction fiber stream with a high-pressure jet gas flow that entrains all the fine particles, and then a laminated fiber web 1 having at least one side constituted by the fiber web-I is formed; This is a method for producing a nonwoven fabric containing fine powder particles, which comprises subjecting one side of the laminated fiber web to a densification treatment.

Furthermore, the nonwoven fabric containing fine powder particles of the present invention is obtained by laminating a fibrous web containing one type of fine powder particles and/or 9 or 8 particles having different particle sizes, and subjecting at least one side to a densification treatment. This is a method for producing a nonwoven fabric containing the above-mentioned fine powder particles.

In other words, when forming a fiber web using a melt blowing method using a thermoplastic polymer or a thermoplastic polymer containing additives, the present invention involves adding fine powder to the high-pressure jet gas stream used to form the fiber stream. By accompanying
Since the fine particles are collected in the fiber web along with the fiber flow, they can be uniformly introduced into the fiber space, and the fine particles can be blown directly onto the surface of the fibers that have been spun from the spinning orifice and have not yet been fully assimilated. Because of this, part of the fine particles becomes embedded in a part of the fiber surface, increasing the effect of collecting the other fine particles.

Therefore, the fine powder particles can be supported uniformly and stably in the fiber web. The thermoplastic polymer used in the present invention is not particularly limited, but
It is a polymer that can be formed into a fibrous web using the melt-blown method. For example, olefin polymers such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene/butene copolymer, ethylene/octene copolymer, ethylene/vinyl acetate copolymer, ethylene/vinyl alcohol copolymer, styrene Copolymers, vinyl chloride polymers, vinylidene chloride polymers, polyamides such as 6-nylon, 6-row nylon, 610-nylon, 8-nylon, and 11-nylon, polyethylene terephthalate,
Polyesters such as ethylene terephthalate copolymers and polybutylene terephthalate, thermoplastic polyurethanes,
It is a dead polymer selected from the group such as thermoplastic polyester elastomers. In spinning one polymer, one type of thermoplastic polymer is melt-spun alone. Thermoplastic polymer 2
The seeds or more are mixed and melt-spun. The two types of thermoplastic polymers are 281 or more melted in separate melting systems.

In the spinning system, the melt flows are integrated or divided and integrated repeatedly to form a composite flow or a mixed flow, which is then melt-spun. When two or more types of polymers are completely melt-spun, one type of polymer can be used as a thermal binder component when forming a nonwoven fabric by combining polymers that soften or melt at lower temperatures than other polymers.

Further, the thermoplastic polymer has a melt viscosity of 500 voids or less, preferably 300 to 50 voids, at the spinning temperature. If the melt viscosity is too high, the spun fibers will not be thick and a fibrous web with good ability to support fine particles will not be obtained.

Next, the fine powder to be supported on the fiber web of the present invention is selected depending on its intended use. For example, inorganic materials include activated carbon, zeolite, alumina-silica sintered powder,
Natural stone fine powder (e.g. 1 Kyoto Shiroishi, bentonite,
Maihanseki 1 limestone, diatomaceous earth, etc.) silica gel, activated alumina, etc. Organic substances include ion exchange resins, metal ion capture compounds, polymeric water-absorbing agents, polymeric oil-absorbing agents, and although they are solid at room temperature, Organic substances that are liquid or sublimated gas in the gas stream (e.g. naphthalene,
The fiber mat contains one selected from camphor, insect repellent, fragrance, etc., or Fi2m or more. The size of the fine powder particles is such that it can be entrained in the high-pressure one-shot gas flow for spinning. Preferably, it is a fine granular material with a particle size smaller than that which can be sieved through a 50-mesh sieve. For particles with a small apparent density or when the pressure of the injected gas flow is high, the particle size may be large, but for particles with a large apparent density or when the pressure of the injected gas flow is low, the particle size may be large. 1. The particle size is also determined based on the intended use of the nonwoven fabric containing fine powder particles. The amount of fine powder contained in the nonwoven fabric is at least 3
0! % by weight, preferably from 50% to 300% by weight. If the content is low, the effect of the official fine powder particles will be lost. On the other hand, if the content is high, the amount of shedding from the nonwoven fabric increases.

A fibrous web containing the fine powder of the present invention is subjected to a densification treatment on at least one side. In the densification process, the temperature of the roller or belt-like surface with a smooth or satin finish is raised to about 50°C, and at least a portion of the fibers softens or melts.
At least the heat-treated surface of the fiber web retains its fiber shape, but adhesion is formed at the contact area of the fibers, resulting in a pseudo-membrane-like state or the fiber shape on the surface. The surface has been shaped into a pseudo-membrane-like state in which at least a portion of the surface has disappeared. A favorable state of this aspect! n4 is a surface that can prevent the fine particles contained in the fiber web from falling off, but has many fine voids through which liquid or gas can freely pass. Thereby,
Fine particles can be stably supported in the nonwoven fabric.

In addition, in the fiber Kuep, which contains a large amount of fine powder,
It may not be possible to form a sufficiently densified surface. In that case, a fiber web containing fine particles with a basis weight of 10 to 100 f/m' or a low content fiber web with a fine particles content of less than 30% by weight is used as a fiber web containing fine particles and high content fibers. A large amount of fine particles can be stably supported in the nonwoven fabric by forming an adhesive laminated nonwoven fabric on one or both sides of the web by thermal bonding of fibers or adhesive bonding, and shaping one surface.

Another structure of the nonwoven fabric containing fine particles of the present invention is that two or more types of fine particles with different properties or two or more types of fine particles with different actions and effects are contained in one nonwoven fabric. 7. When trying to obtain a desired product, these two or more types of fine particles can be mixed to form a homogeneous mixed system and be accompanied by the high-pressure jet gas flow for spinning, and the effects of the fine particles can be If the effect is not impaired, a nonwoven fabric containing mixed fine particles and 1. It's okay. 17 However, for those in which the respective fine particles cannot form a mixed system, a fibrous web containing each fine powder and granules is made, and these fiber webs are laminated to form a laminated nonwoven fabric. A nonwoven fabric that exhibits the following effects can be obtained.

In addition, the thermoplastic polymer constituting the nonwoven fabric of the present invention includes:
Various additives may be added as necessary. Examples of additives include fiber colorants, heat stabilizers, light stabilizers, softeners, and hydrophilic agents.

By adding a flame retardant, a water generating agent, etc., it is possible to improve the usage characteristics of the nonwoven fabric fibers and to enhance the effect of the fine particles contained in the nonwoven fabric. For example, a nonwoven fabric made of a fibrous web made of carbon black colored fibers containing sintered alumina-silica powder is effective as a seedling-raising sheet that has excellent heat retention effects and excellent air permeability and water permeability. Non-woven fabrics made of fibers with added light and heat stabilizers and containing activated carbon are effective for covering and fencing outdoor waste disposal. In addition, a nonwoven fabric made of a fiber web made of fibers containing a hydrophilic agent and containing a metal ion-trapping compound and fine limestone powder is effective as a temporary material for industrial wastewater.

[Effect]

In the present invention, when preparing a fiber web using the melt-prone method, by entraining the fine powder particles to a high-pressure jet gas flow, the fine powder particles partially form a sticky layer on the fiber surface and are uniformly dispersed in the fiber web. It can be included. Furthermore, since the space between the fibers is smaller than that of a fibrous web made using ordinary fibers, it has a better ability to support fine particles. Therefore, the functions and effects of the fine powder particles can be fully exerted.

〔Example〕

Next, two embodiments of the present invention will be explained using specific examples, but the present invention is not limited to these examples. Note that parts and parts in the examples refer to weight unless otherwise specified.

Example 1 Highly fluid polypropylene with a melt flow rate (hereinafter referred to as MFR) of 33 was charged into a melt extruder.

Melt at 280℃ and drill a hole with a nozzle diameter of 0.31118 mm.
- Width 0.25cm on both sides of spinning holes arranged in a row at intervals
Using a die head equipped with a slit-shaped gas outlet, the die temperature was 280°C, the heated air temperature was 300°C, and the pressure was 2.
．． When spinning at a discharge rate of 0.2 f/min per spinning hole under conditions of 5 Kq/-, finely ground zeolite (granules passed through a 140-mesh sieve) was used as a substance to accompany the jet air flow. Approximately 25cm below the spinning hole with the ejected fiber flow
The fibers were collected by a reticular belt conveyor collector running at the position yn to obtain a fiber web with an average basis weight of 150 f/m' containing about 122% zeolite based on the fibers. This fibrous web is transferred onto a metal calendar belt stretched between a heating drum and a cooling drum, is press-bonded in a heating zone heated to a temperature of 125°C, and is cooled to about 65°C in a cooling section and peeled off. As a result, the surface in contact with the calendar belt was a nonwoven fabric in which the fibers were bonded together while most of the fibers maintained their shape, forming a pseudo-membrane-like surface. In this nonwoven fabric, fine zeolite powder was homogeneously distributed, and there was almost no shedding of the fine powder under normal nonwoven fabric processing conditions.

This zeolite-containing nonwoven fabric was also suitable as a water filter material.

Example 2 When producing the polypropylene fiber web of Example 1 by the melt-blown method, activated carbon powder (granular material passed through a 100 mesh sieve) was used as a substance to be entrained in the jetted air stream, and was used together with the spun jetted fiber stream. Collected in a collection device 7,
Average basis weight: 118, including approximately 90 grams of activated carbon per fiber
A fiber web of //rrf was obtained. This fiber web 12
Both surfaces were subjected to densification treatment by contacting with a calender roll surface heated to 5°C.

In the obtained nonwoven fabric, activated carbon was homogeneously dispersed and stably supported between the fibers. This nonwoven fabric was processed into a simple gas mask and was suitable for use in workplaces with a lot of dust and mist. Furthermore, this nonwoven fabric sheet was effective in reducing bad odors when used to cover waste that emitted odors.

Example 3 Zeolite-containing fibrous web obtained in Example 1 and Example 2
The fiber web containing activated carbon is alternately laminated with 4 layers and then the average basis weight on both sides is 30 fly! The polypropylene fiber webs obtained by the melt-prone method of Example 1
A nonwoven fabric with densification on both sides was produced by heat treatment using the method described in the following.

This nonwoven fabric was suitable for use as a household drinking water purification filter. It could be used to purify well water and as a simple water purification filter.

Example 4 When polyethylene containing a hydrophilic agent (manufactured by The Dow Chemical Company, trade name ASPUN 6809) was spun using the melt prone spinning apparatus of Example 1, the Gui temperature was 280°C,
When spinning at a discharge rate of 0.2 f/min from the spinning hole under conditions of a heated air temperature of 300°C and an air pressure of 1.2 P/-, alumina-silica sinter is used as a substance to accompany the air flow. Powder (granular material passed through 14o mesh)
An average basis weight of 135 cm is collected with a collection device along with the spun jet fiber stream, and contains about 87 inches of powder per fiber. /d
made a fibrous web. This fibrous web is 110'C
Both sides were densified using calender rolls heated to 100 mL to obtain a nonwoven sheet-like material.

When this nonwoven sheet-like material is used as a sheet for raising seedlings, plants can be cultivated without causing root entanglement.

Example 5 In producing the polypropylene fiber web of Example 1 1
7. Fine granular silica gel, activated alumina (mixing ratio 1:1), and camphor are used as substances accompanying the jet air flow, and are collected together with the spun jet fiber flow, and the amount of about 10
A fibrous web containing 9% powder and having an average basis weight of 752/cm was obtained. This fibrous web was densified using a calendar roll to obtain a non-woven sheet with a smooth surface. It was suitable.

〔Effect of the invention〕

The present invention is a high-pressure injection method used when forming a fibrous web by the melt-prone method, unlike those that are added to fibers and made to exist in fine particles by kneading, or in which fine particles are fixed to fibers by a binder. By bringing the fine particles into the gas flow, some of the fine particles that come into contact with the fiber surface during the fiber formation process stick to the fibers, and the fine particles collected along with the fiber flow are incorporated into the fiber web. Distribute homogeneously.

Furthermore, since the space between fibers can be made small, the ability to support fine powder particles is good. Accordingly, the characteristics possessed by -0 fine powder particles,
0 Patent applicant RiRa Shi Co., Ltd.

Claims (2)

[Claims] (1) Heat and melt a thermoplastic polymer or a thermoplastic polymer containing additives and discharge it from a spinning orifice,
The discharged melt is pulled by a high-pressure jet gas flow accompanied by fine powder and granules to form a fiber stream, and the fiber stream is collected on a collection surface to create a fiber web containing at least 30% by weight of fine powder and granules. ,
A method for producing a nonwoven fabric containing fine powder particles, characterized in that at least one side of the fibrous web is subjected to a densification treatment. (2) heating and melting a thermoplastic polymer or a thermoplastic polymer containing additives and discharging it from a spinning orifice;
When the discharged melt is pulled into a fiber stream by a high-pressure jet gas flow and the fiber stream is collected on a collection surface to create a fiber web, (a)
The fibers are drawn by a high-pressure jet gas flow that does not contain fine powder particles or is accompanied by fine powder particles to form a fiber web I containing 0 to less than 30% by weight of fine powder particles; A fibrous web containing at least 30% by weight of fine powder and granules, which is made into a traction fiber stream by a high-pressure jet gas flow accompanied by -I
A nonwoven fabric containing fine powder particles, characterized in that a laminated fiber web is formed in which the fiber web I forms at least one side of the fiber web I, and the fiber web I side of the laminated fiber web is subjected to a densification treatment. manufacturing method.