JPS58203117A - Polyester type thermosetting binder fiber - Google Patents

Abstract

PURPOSE:The titled binder fibers, consisting of a polyester resin having a specific softening point and melt viscosity and a curing agent, capable of bonding well the interstices between fibers of textile products, e.g. nonwoven fabrics, with a slight deterioration in the adhesive strength. CONSTITUTION:Polyester type thermosetting binder fibers prepared by mixing 100pts.wt. polyester resin having 80-180 deg.C, preferably 90-160 deg.C, softening point, 5X10<2>-1X10<5> poises melt viscosity at 180 deg.C and preferably 5-40mgKOH/g hydroxyl number with preferably 5-30pts.wt. curing agent, e.g. a polyfunctional isocyanate compound, and melt spinning the resultant mixture at a low temperature for a short time. USE:A binder for nonwoven fabrics, synthetic paper, waddings, mattresses, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyester thermosetting binder fiber that has excellent adhesive properties and good thermal stability after bonding.

Recently, in fiber molded products such as roof ink materials, automobile interior parts, nonwoven fabrics such as base fabrics for textile products, stuffing for pillows and bedding, stuffing for quilting, and stuffing for pine tresses, the constituent fibers 1, such as polyester, polypropylene, Hoctomel type binder fibers are now being used in place of binders such as polyvinyl alcohol and modified acrylic acid polymers that have been conventionally used to bond nylon and acrylic fibers.

Such textile products meet the performance requirements for which they are required.

For example, nonwoven fabrics have excellent properties such as strength, elongation, and rigidity, and wire connections and pine tresses have excellent properties such as bulkiness and elastic recovery.

Polyester fibers now account for most of the material, and as a binder fiber for bonding these fibers, US Pat.
Thermoplastic binder fibers are disclosed in Japanese Patent Publication No. 76, Japanese Patent Publication No. 54-38214, and the like. The melting point of the low melting point component polyester that makes up these binder fibers is 80.
It is in the range of ~200C and is heat treated near the melting point to achieve adhesion between fibers. However, when these fiber products are used as industrial materials in a high-temperature atmosphere of 80 to 200°C, the adhesive strength decreases, resulting in a decrease in product strength, an increase in elongation, and a decrease in bulk retention, making it difficult to use. There's a problem.

The present inventors conducted various research on binder fibers that effectively bond the fibers of textile products made of polyester fibers as described above, and which exhibits less decrease in adhesive strength even in high-temperature atmospheres, and as a result, they have arrived at the present invention. It is something.

That is, the present invention has a softening point of 80 to 180C, 180C.
The gist is a polyester thermosetting binder fiber made of a polyester resin with a melt viscosity of 5 x 102 to 1 x lO) and a curing agent.

In the present invention, any curing agent may be used as long as it does not react much with the polyester resin during spinning and easily reacts during adhesive heat treatment to harden the polyester resin, but one representative example is polyvalent incyanate. Examples include compounds. Specific examples of polyvalent isocyanate compounds include:

Diphenylmethane diisocyanate, tolylene diisocyanate, triphenylmethane triisocyanate, tetramethylene diisocyanate, trimethylhexamethylene diisocyanate, 1xamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, lysine diisocyanate, etc. and these isocyanate compounds as ξ-caprolactam Examples include blocked isocyanate compounds blocked with alcohol, lower alkyl ester of p-oxybenzoic acid (alkyl group having 1 to 6 carbon atoms), and the like. Blocked isocyanate compounds are preferably used because they do not cause any reaction during spinning, but free incyanate compounds can also be used if a rapid mixing yarn spinning pack as shown in FIG. 1 is used.

The polyester resin used in the present invention has a softening point of 80
It is a resin that has fiber-forming properties at ~180°C.

Particularly preferred are those having a softening point of 90 to 160c.

If the softening point is below 80℃, the normal operating temperature 1, for example 30~
Even at about 40°C, the adhesive strength is weak and cannot be put to practical use. If the softening point is 180° C. or higher, the spinning temperature in the spinning process becomes high, the reaction with the curing agent progresses, and the spinning condition deteriorates. Furthermore, in order to improve the spinning condition, the melt viscosity at 180℃ was set to 5.
It is necessary to have 10 × 10 to I × 10 voices.

Outside this range, the spinning condition will be poor, leading to problems such as the occurrence of stuck yarns, increased yarn breakage, and increased unevenness in fineness. In addition, in order to promote the curing reaction during adhesion, it is preferable that the hydroxyl value of the polyester resin is 5 to 40 ■KO) (/I. If it is 5 or less, the degree of crosslinking due to the curing reaction is low, and the adhesion during high temperature use The strength does not increase.If it is 40 or more, a curing reaction progresses during spinning, resulting in poor spinning quality.

Examples of such polyester resins include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalene dicarboxylic acid, lower alkyl esters thereof, and p-oxybenzoic acid.

One or more acid components selected from oxyacids such as p-oxyethoxybenzoic acid, polyhydric carboxylic acids such as trimellitic acid and trimesic acid, and ethylene glycol, 1,2-
Propanediol, 1,3-propanediol, 1,3
-butanediol, 1.4-butanediol, 1.6-
Prepared by the following method from one or more alcohol components selected from polyhydric alcohols such as hexanediol, diethylene glycol, neopentyl glycol, dihydric alcohol, trimethylolethane, trimethylolethane, pentaerythritol, etc. be done.

That is, 11 of the lower alkyl ester of the acid component mentioned above.
11 or more and one or more of the above-mentioned alcohol components in the presence of a catalyst at 150 to 250°C, the resulting alcohol is removed from the system to obtain a low polymer, and the low polymer is ashed. Polymer under reduced pressure.

After polycondensation at 200-290°C to form a high polymer.

It can be prepared by depolymerizing using a divalent or trivalent or higher polyhydric alcohol. Also.

It can also be prepared solely by polycondensing the above-mentioned low polymer, but in this case, compared to the above-mentioned method, there is a drawback that it is difficult to repeatedly and stably prepare a polyester resin of constant quality.

The appropriate amount of curing agent to be added to the polyester resin is an amount that is approximately the same equivalent as the hydroxyl value of the polyester resin.
Generally, 5 parts of curing agent per 100 parts by weight of polyester resin.
It is blended in a proportion of ~30 parts by weight.

When a polyester resin and a curing agent are mixed and spun, it is necessary to perform the spinning at as low a temperature as possible and in a short time. Otherwise, the curing reaction will proceed and the spinning condition will deteriorate due to yarn breakage, etc. The mixing and spinning time is preferably about 0.5 to 10 minutes, and a rapid kneading spinning pack as shown in FIG. 1 may be used. In Fig. 1, 1 is a pack block, 2 is a polyester resin inflow pipe, 3 is a curing agent introduction tube, 4.5
6 is a static kneading element, 6 is a threading part, 7 is a spinneret, 8 is a wire mesh filter, 9 is a pressure plate, 10 is a spinning hole, and 11 is a presser plate. The polyester resin and curing agent in a molten state are separately calculated by a gear pump and supplied to the mixed wire spinning pack, where they are mixed and spun.

1. When the binder fiber of the present invention is to be used for stuffing pine cloth, it is used by being mixed with a pace fiber in a card or the like. Therefore, in order to improve the blending in the card and prevent the card from sinking, it is preferable to have a fiber form similar to that of the pace fiber, which is cut into 20 to 150 grains and crimped. Also.

When making a nonwoven fabric, it is mixed with base fibers and cut to the same length as the pace fibers, for example, 2 to 30 mK, so that they are dispersed as uniformly as possible. Needless to say, the fineness, cut length, crimp form, etc. of the paper-formed binder fibers may be varied depending on the use.

Note that the binder fibers of the present invention are not limited to single-component fibers, but include composite fibers 9 in which a component consisting of a polyester resin and a curing agent forms the fiber surface portion, such as sheath-core type and seabird type composite fibers. It can also be fiber. When forming composite fibers, the other components may be those that can be melt-spun into composite fibers, and polyethylene terephthalate and nylon are suitable.

Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples. Note 9
"Parts" in the examples mean parts by weight.

Note that the measuring method used in the present invention is as follows.

Hydroxyl value: Based on the hydroxyl value test method of JIS-KOO70 Chemical (2) products, and the unit is qWl.

Melt viscosity: Using a high slag flow tester type 301, cylinder area 4-, nozzle I, /D = 20 x 10.5 m, extrusion pressure 52.5? /!
.

After reaching the measurement temperature of 180°C at a heating rate of 6°C/min under the condition of a sample amount of 5II, the temperature was held for 5 minutes, and the bottle was melted at the above pressure. Discharge from the nozzle, measure the plunger descent length and the required time, and calculate according to the following formula.

Melt viscosity (voids) = 39.4/discharge rate Softening point: This is the temperature at which the polymer starts to deform.

Using the Yanagimoto automatic melting point measuring device, Needle insertion temperature into polymer in cone bath Find the degree.

Tensile Strength of Synthetic Paper Crab binder fibers and base fibers are dispersed in water, paper is formed on a screen, and then dried with a Yanki set dryer and heat treated to melt and bond.The tensile strength of the resulting synthetic paper is Sawo JIS P-8113-197
Measure according to 6.

Reference Example 0.44 part of zinc acetate was added as a catalyst to the raw materials shown in Table 1, and a transesterification reaction was carried out at 160 to 240°C.

The theoretical amount of methanol was distilled off. followed by 0.58 parts of antimony trioxide and trimethylphosphny)
0.48 part was added and a polycondensation reaction was carried out at 275° C. and a degree of vacuum of 0.1 torr to produce polyester. Add 52 parts of trimethylolpropane to this polyester and heat at 275°C.
A depolymerization reaction was carried out under nitrogen pressure to produce a polyester resin having the characteristic values shown in Table 1.

Table JIII Example 1 The polyester resin of Reference Example 2 was melted using a normal fiber extruder, measured using a gear pump, and then placed in a rapid kneading spinning pack with 41. It was.

15 parts (H
He weighed the fiber (manufactured by iiLS), introduced it into a rapid blend spinning pack, and mixed it with polyester resin at 180°C, 60
The yarn was wound up at a speed of 0 m/m.

The spinning conditions are shown in Table 2. Polyester resin B did not form threads at a spinning temperature of 180°C, and although a test was conducted by lowering the spinning temperature to 150°C, cohesive threads were generated. With polyester resin, the spinning condition is poor at a spinning temperature of 180℃.
Although spinning was carried out at 0C, thread breakage occurred frequently, probably due to the progress of the reaction between the resin and the curing agent. Polyester resin A, B
, C, and E were cut with a push-cut cutter to obtain thermosetting binder fibers with a fineness of 3 denier and a fiber length of 5 m+.

20 parts of the binder fiber thus obtained and 80 parts of polyester fiber of 12 denier and fiber length of 5III prepared separately made of normal polyethylene terephthalate were dispersed in water, and the mixture was run on a paper machine K equipped with a papermaking net and a Yanki set dryer. Amount 4511/pp? Synthetic paper (a-
e) was obtained. The surface temperature of the Yankee complete dryer is 200
℃, and the treatment time was 15 minutes. .

Separately, using only the polyester resin A described in E and binder fibers with no curing agent mixed, the same method was used.
46 g/- of synthetic paper (f) was obtained.

The tensile strength of the synthetic paper thus obtained is determined by the atmospheric temperature of 25°C and 1
As a result of measurement at 50°C, the values shown in Table 2 were obtained.

[Table 2 When using the polyester resin and curing agent according to the present invention,
There was no yarn breakage during spinning, and the dispersion state during paper making was also good. The paper strength was good when measured at 25C, and there was no significant decrease when measured at 150C.

Example 2 Using 100 parts each of the polyester resins A, C, and E of the reference example and 15 parts of hexamethylene diisocyanate (formerly LS Co., Ltd.) blocked with C-caprolactam as a curing agent, a rapid mixed wire spinning pack similar to that of Example 1 was prepared. Spun at 180℃ using 41! I got tired at a speed of 500 m/h. The yarn was cut with a push cutter to obtain thermosetting binder fibers with a fineness of 6 denier and a fiber length of 10 m.

A polyester fiber made of polyethylene terephthalate for paper making with a fineness of 4 denier and a fiber length of 10 cm When the polyester resin and curing agent according to the present invention were used, there was no yarn breakage during spinning and the dispersion state during paper making was good. The paper strength did not decrease significantly even when measured at 150°C.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a rapid blending spinning pack suitable for spinning the binder fiber of the present invention. 2... Polyester resin inflow pipe, 3... Curing agent introduction capillary, 4.5... Static kneading element, 7... Spinneret. Patent Applicant Nippon Estel Co., Ltd. Agent Yu Kodama 3rd 10th

Claims (3)

[Claims] (1) A polyester thermosetting binder fiber consisting of a polyester resin having a softening point of 80-180°C and a melt viscosity of 5X10''-IXIO5 voids at 180C and a curing agent. (2) The poly5 ester thermosetting binder fiber according to claim 1, wherein the curing agent is a polyvalent incyanate compound. ″ (3) Polyester resin has a hydroxyl value of 5 to 40 wII
KO) t/i polyester thermosetting binder fiber according to claim 1.