JP2003096427A - Flame retardant adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a halogen-free flame retardant adhesive for flat cables and having sufficient flame retardancy and adhesivity. SOLUTION: An adhesive layer 2 of which an adhesive film 3 for a flat cable is constituted, is formed by using a flame retardant adhesivity containing 100 pts.wt. of a modified polyester resin, 10-100 pts.wt. of a nitrogen-containing organic flame retardant and 0-5 pts.wt. of a halogen-free flame retardant. The modified polyester resin is obtained by modifying so that 3-50 of phosphoric acid residues and 1-50 of maleic acid or oleic acid residues are contained based on 1,000 of carbon atoms in the polyester resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halogen-free flame-retardant adhesive used for flat cables, flexible printed boards and the like.

[0002]

2. Description of the Related Art A flat cable having a structure in which a plurality of line-shaped conductors are covered with two adhesive films each having an adhesive layer formed on a base film is known. Such flat cables are widely used for internal wiring of computer equipment and high-density mounted AV equipment.

By the way, in this flat cable, good flame retardancy is required for its constituent materials from the viewpoint of disaster prevention, and flame retardancy is also required for its adhesive layer. For this reason, as an adhesive forming the adhesive layer, a mixture of a small amount of a halogen-based flame retardant such as decabromodiphenyl ether and a mixture of a large amount of a non-halogen-based flame retardant such as magnesium hydroxide has been investigated.

However, with a halogen-based flame retardant-added adhesive, harmful halogen-containing gas is generated during waste incineration, and therefore its use cannot be avoided. Further, in the case of an adhesive to which a non-halogen flame retardant is added, in order to obtain sufficient flame retardancy, the amount of the additive is increased, so that there is a drawback that the adhesive strength is reduced.

[0005]

Therefore, an object of the present invention is to make a flame-retardant adhesive used for a flat cable or the like non-halogen and have sufficient flame retardancy and adhesiveness. It is in.

[0006]

This problem is solved by a modified polyester modified to have 3 to 50 phosphoric acid residues and 1 to 50 maleic acid residues or oleic acid residues per 1000 carbon atoms. A flame-retardant adhesive containing 100 parts by weight of a resin, 10 to 100 parts by weight of a nitrogen-containing organic flame retardant, and 0 to 50 parts by weight of a halogen-free flame retardant.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
FIG. 1 shows an example of the flat cable of the present invention. In the figure, reference numeral 1 indicates a base film. The base film 1 is made of a plastic such as saturated polyester such as polyethylene terephthalate or polyethylene naphthalate, polyimide, polyphenylene sulfide, polyethylene, polypropylene or polyamide.
It is a 200 μm film.

An adhesive layer 2 having a thickness of 15 to 100 μm is formed on one surface of the base film 1 to form an adhesive film 3. The two adhesive films 3 are laminated so that the adhesive layers 2 and 2 face each other, and a plurality of flat rectangular conductors 4 and 4 are sandwiched between them to be bonded to each other. The flat cable of is configured.

A flame-retardant adhesive is used as an adhesive for forming the adhesive layer 2 of the adhesive film 3.
This flame-retardant adhesive contains a modified polyester resin, a nitrogen-containing organic flame retardant, and a halogen-free flame retardant as essential components.

The above-mentioned modified polyester resin is synthesized such that the number of phosphoric acid residues is 3 to 50, and the number of maleic acid residues or oleic acid residues is 1 to 50 per 1000 carbon atoms of the molecule of the polyester resin. However, it itself has appropriate flame retardancy and adhesiveness.

As the modified polyester resin here,
For example, acid components such as terephthalic acid, isophthalic acid, diphenylcarboxylic acid, adipic acid and sebacic acid,
A phosphoric acid-containing acid component such as (9,10-dihydro-9-oxa-10-oxide-10-phosphophenanthren-10-yl) methylsuccinic acid, maleic acid or oleic acid, ethylene glycol, 1,4 -Saturated polyesters obtained by esterification reaction and polycondensation reaction with alcohol components such as butanediol, 1,4-dicyclohexanedimethylol, diethylene glycol and neopentyl glycol are used alone or in combination of two or more. Further, the number of each acid residue is controlled within the above range by adjusting the compounding amounts of the above-mentioned phosphoric acid-containing acid component and maleic acid or oleic acid.

Specifically, for example, terephthalic acid 20 to 1
00g, isophthalic acid 10-50g, sebacic acid 50-
100 g, 2- (9,10-dihydro-9-oxa-1
0-Oxide-10-phosphophenanthrene-10-
Yl) methylsuccinic acid 50 to 150 g, maleic acid or oleic acid 50 to 150 g, neopentyl glycol 60 to 80 g, and ethylene glycol 30 to 50 g are put in a reactor, and after the inside of the reactor is replaced with nitrogen, 10 to 50 r
While stirring at pm, the reactor is heated to 230-250 ° C to melt the contents. The temperature in the reactor is 230-25
After reaching 0 ° C, the esterification reaction is carried out for 3 to 5 hours. Next, 4 to 5 g of a 1 to 3 wt% ethylene glycol solution of zinc acetate as a catalyst was placed in the reactor, and the temperature of the reactor was adjusted to 2
While increasing the temperature to 70 to 290 ° C., the pressure is reduced to 0.5 hPa, and the polycondensation reaction is performed at this temperature for 2 to 7 hours. When the reaction is completed, the pressure is returned to normal pressure while introducing nitrogen into the reactor, and the molten state is formed into a sheet, which is cooled and solidified. From the above, 200 to 400 g of modified polyester resin is obtained.

In this modified polyester resin, if the number of phosphoric acid residues is less than 3 per 1000 carbon atoms, the flame retardancy is insufficient, and if it exceeds 50, the adhesive strength is reduced. If the number of maleic acid residues or oleic acid residues is less than 1, the adhesive strength will be insufficient, and if it exceeds 50, the breaking load of the adhesive layer will decrease.

The nitrogen-containing organic flame retardant is a non-halogen flame retardant and does not reduce the electric resistance of the adhesive layer. Specific examples of the nitrogen-containing organic flame retardant include:
One or a mixture of two or more of cyanuric acid triamide, cyanuric acid diamide, cyanuric acid monoamide, melam, melamine cyanurate, melamine resin, homoguanamine, benzoguanamine, acetoguanamine and the like can be mentioned.

Among these, melamine isocyanurate is particularly preferable from the viewpoints of dispersibility, mixability, adhesion to the modified polyester resin. The nitrogen-containing organic flame retardant is added in an amount of 10 to 100 parts by weight with respect to 100 parts by weight of the modified polyester resin. If it is less than 10 parts by weight, the flame retardancy is insufficient, and if it exceeds 100 parts by weight, the adhesive strength, Mechanical properties deteriorate.

As the non-halogen flame retardant, metal hydroxides such as magnesium hydroxide, aluminum hydroxide and calcium hydroxide, and phosphorus flame retardants such as ammonium polyphosphate, red phosphorus and melamine polyphosphate are used. Among these non-halogen flame retardants, aluminum hydroxide, magnesium hydroxide and the like are preferable because they have a particularly high flame retarding effect.

The amount of the halogen-free flame retardant added is set to 0 to 50 parts by weight with respect to 100 parts by weight of the modified polyester resin, and if it exceeds 50 parts by weight, the adhesive strength is lowered. This non-halogen flame retardant does not need to be added depending on the required flame retardancy, but the metal hydroxide also functions as an inorganic filler, increasing the rigidity of the adhesive layer and consequently increasing the adhesive strength. Since it improves, it is preferable to add it within the range where it does not become excessive.

In the flame-retardant adhesive of the present invention, various additives such as an organic solvent, an antioxidant, a metal corrosion inhibitor, a colorant and various coupling agents are added within a range not impairing the effects of the present invention. , A crosslinking agent, a crosslinking aid, a filler, and an antistatic agent may be appropriately added. As the organic solvent, ketones such as methyl ethyl ketone and methyl isobutyl ketone, esters such as ethyl acetate and butyl acetate, and aromatics such as toluene are used.

The flame-retardant adhesive of the present invention comprises 100 parts by weight of a modified polyester resin and 10 to 10 nitrogen-containing organic flame retardants.
It can be produced by uniformly mixing 0 parts by weight, 0 to 50 parts by weight of a non-halogen flame retardant, and optionally other additive components. The adhesive of the present invention may be in the form of a solution, paste, pellet, or the like. To form an adhesive layer of a flat cable, it is used as a solution type by applying it to a base film. In addition to
It is common to extrude pellets from an extruder onto a substrate film to form a film for use.

Further, the flat cable of the present invention uses the adhesive film formed as described above, sandwiches the conductor, and pressurizes it with a pressure roll, a pressure press, etc., at the same time, at a temperature of 80 It is produced by heating to ~ 200 ° C. Generally, a method of using a heating and pressing roll and continuously adhering is widely used in terms of workability and the like.

In such a flame-retardant adhesive, the base polymer thereof has 3 to 50 phosphoric acid residues and 1 to 50 maleic acid residues or oleic acid residues per 1000 carbon atoms. A modified polyester resin modified so that 100 parts by weight of the modified polyester resin, 10 to 100 parts by weight of a nitrogen-containing organic flame retardant, and 0 to 50 parts by weight of a non-halogen flame retardant are used, so that it is good. It exhibits excellent adhesive strength and has high flame retardancy. Further, since it is non-halogen, no harmful halogen-containing gas is generated even if it is incinerated.

Further, the flat cable similarly exhibits good adhesive force and has high flame retardancy. Further, since it is non-halogen, no harmful halogen-containing gas is generated even if it is incinerated. Therefore, this flat cable can be used for wiring or the like of computer equipment or the like that requires flame retardancy.

A specific example will be shown below. Compositions (parts by weight) shown in Tables 1 and 2 were dissolved in a mixed solvent consisting of 1 part by volume of methyl ethyl ketone and 4 parts by volume of toluene to prepare a solution-type adhesive having a resin content of 30 wt%. This solvent-type adhesive was applied onto a polyethylene terephthalate film having a thickness of 25 μm with a bar coater and dried to form an adhesive layer having a thickness of 35 μm to prepare an adhesive film.

With respect to the adhesive film thus obtained, the adhesive strength, breaking load, tensile elongation and oxygen index were measured. As for the adhesive force, the two adhesive films were adhered at a speed of 0.5 m / min, a temperature of 160 ° C. and a pressure of 1.0 MPa, and the T-shaped peeling force of this was measured.

The breaking load and the tensile elongation are 10 mm in width,
The central portion of the adhesive film having a length of 200 mm was marked at intervals of 50 mm, and this was pulled at a speed of 200 mm / min to measure the strength and elongation at break of the film. The oxygen index was measured by a flame retardant oxygen index measuring device.

In Tables 1 and 2, "polyester resin 1" is an unmodified polyethylene terephthalate resin having a molecular weight of 20,000 and a glass transition point of 30 ° C, and "polyester resin 2" is a molecular weight of 20,000 and a glass transition point of 30 ° C. , 1 phosphoric acid residue and 10 maleic acid residue per 1000 carbon atoms
The modified polyethylene terephthalate resin is shown below.

The "polyester resin 3" has a molecular weight of 20,000,
A modified polyethylene terephthalate resin having a glass transition point of 30 ° C., 60 phosphoric acid residues and 10 maleic acid residues per 1000 carbon atoms, “polyester resin 4” has a molecular weight of 20,000, a glass transition point of 30 ° C., carbon atoms. Modified polyethylene terephthalate resin containing 5 phosphoric acid residues and 0.5 maleic acid residues per 1000

The "polyester resin 5" has a molecular weight of 20,000,
A modified polyethylene terephthalate resin having a glass transition point of 30 ° C., 5 phosphoric acid residues and 1000 maleic acid residues per 1000 carbon atoms is shown. "Polyester resin 6" is
A modified polyethylene terephthalate resin having a molecular weight of 20,000, a glass transition point of 30 ° C., phosphoric acid residues of 5 and maleic acid residues of 10 per 1000 carbon atoms is shown. The results are shown in Tables 1 and 2.

[0029]

[Table 1]

[0030]

[Table 2]

From the results of Tables 1 and 2, there are 3 to 50 phosphoric acid residues and 1 to 1 maleic acid residues per 1000 carbon atoms.
A modified polyester resin modified to have 50 is used, and one containing 100 parts by weight of the modified polyester resin, 10 to 100 parts by weight of melamine cyanurate, and 0 to 50 parts by weight of aluminum hydroxide is preferable. It can be seen that the adhesiveness is exerted and the flame retardancy is high.

[0032]

As described above, the flame-retardant adhesive of the present invention has 3 to 5 phosphoric acid residues per 1000 carbon atoms.
0, 1 to 50 maleic acid residues or oleic acid residues
Since it contains 100 parts by weight of the modified polyester resin modified to be individual, 10 to 100 parts by weight of the nitrogen-containing organic flame retardant, and 0 to 50 parts by weight of the non-halogen flame retardant, it exhibits good adhesive strength, Moreover, it has high flame retardancy. Further, since it is non-halogen, no harmful halogen-containing gas is generated even if it is incinerated.

Further, the flat cable of the present invention similarly exhibits good adhesive force and has high flame retardancy. Further, since it is non-halogen, no harmful halogen-containing gas is generated even if it is incinerated. Therefore, this flat cable can be suitably used for wiring of computer equipment and the like which is required to have flame retardancy.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a flat cable according to the present invention.

[Explanation of symbols]

2 ... Adhesive layer.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01B 7/295 H01B 7/34 BF term (reference) 4J004 AA15 AA17 AA18 AB05 CA04 CA06 FA05 GA01 4J040 EB132 ED121 ED151 GA27 HA056 HA136 HA156 HA286 HC25 HD24 JA09 KA36 LA08 NA19 5G311 CD01 CF06 5G315 CA03 CD08 CD13 CD17

Claims (2)

[Claims] 1. The number of phosphoric acid residues is 3 per 1000 carbon atoms.
~ 50, 1 to maleic acid residue or 1 to oleic acid residue
Modified polyester resin 10 modified to 50
A flame-retardant adhesive containing 0 parts by weight, 10 to 100 parts by weight of a nitrogen-containing organic flame retardant, and 0 to 50 parts by weight of a halogen-free flame retardant. 2. A flat cable obtained by sandwiching and adhering a conductor with an adhesive film having an adhesive layer formed on the surface of a base film, wherein the adhesive layer is made of the flame-retardant adhesive according to claim 1. Flat cable.