JPS61163983A - Organic semiconductor composition - Google Patents

Abstract

PURPOSE:To obtain an org. semiconductor compsn. which does not emit hydro gen cyanide by thermal decomposition, by adding a polyhydric alcohol and a paraffinic hydrocarbon to an org. semiconductor composed of 7,7,8,8-tetra- cyanoquinodimethane salt. CONSTITUTION:An org. semiconductor compsn. is obtd. by adding at least 3pts.wt. additive consisting of a polyhydric alcohol and a paraffinic hydrocarbon to 100pts.wt. ion radical salt of 7,7,8,8-tetracyanoquinodimethane (TCNQ). The additive is effective in inhibiting the emission of hydrogen cyanide. It is believed that in the thermal decomposition of TCNQ salt, a certain radical R is released from its molecule, a chain reaction is induced and rapid thermal decomposition takes places. The polyhydric alcohol and the paraffinic hydrocarbon capture the radi cal and serve as terminators in the chain reaction by combustion or oxidation so that TCNQ is prevented from being decomposed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a new organic semiconductor composition.
The present invention relates to an organic semiconductor composition containing an 8-tetracyanoquinodimethane compound as a main component, in which generation of toxic gas during thermal decomposition or combustion is suppressed.

Conventional technology 7.7,8.8-tetracyanoquinodimethane (hereinafter referred to as τC
NQ) has four nitriles (-CmiN) in the molecule.
Since it is a molecule with strong electron affinity (acceptor) having a group, it forms intermolecular compounds or salts with many molecules with low ionization potential (donor), giving an organic semiconductor with low electrical resistance. As organic semiconductors have the advantage of relatively high thermal stability, their applications in many electronic devices have been proposed.For example, temperature sensors that utilize temperature changes in their resistance, low resistance and electrochemical These include solid electrolytes for solid electrolytic capacitors that utilize activity, logic elements that utilize the electric field of resistance or switchability due to light, and display elements that utilize memory, recording media, and color changes in redox reactions.

Problems to be Solved by the Invention However, although these electronic devices do not pose any safety problems during normal use, they can generate toxic gas in the event of a fire or heat generation due to some kind of overcurrent. It is quite possible. For example, there are four ON groups in the TCNQ molecule (molecular weight = 204), and C
Since the bond between and H is very strong, if thermal decomposition occurs, hydrogen cyanide (HCN, molecular weight = 27) may be produced.

If all four ONs were converted to HCH, 629fi, 9 HCN would be generated per gram of TCNQ molecules. In addition, since those on TCNQCN have sublimation properties,
When heated, it scatters into the air before being decomposed, but organic semiconductors obtained by reacting with various donors always undergo thermal decomposition when left at high temperatures of about 250'C or higher. In addition, since this thermal decomposition is an exothermic reaction, the temperature of the organic semiconductor increases during decomposition, and the decomposition temperature is approximately 30°C, regardless of the starting temperature.
It falls within the range of 0 to 600'C. On the other hand, it is known that this temperature range is the condition in which hydrogen cyanide is most likely to be generated during combustion of organic compounds containing nitrogen. In this way, when using an organic semiconductor made of TCNQ, it is necessary to assume that hydrogen cyanide gas, which is extremely toxic to the human body, will be generated when heating occurs for some reason. In fact, when quinolinium (TCNQ)2, which is known for its low resistance, is thermally decomposed in air at 300"C, hydrogen cyanide and acetonitrile (ca3cN
) was confirmed by gas mass spectrometry to mainly occur.
In particular, hydrogen cyanide was found to be generated in an amount of 4% by weight based on quantitative analysis (pyridine-pyrazolone spectrophotometry) based on JISKO109. This value is the theoretical amount (
63%) YoV is much lower, for example 100m & OTON
Q*t4. (')'2f's'l T*f+% L
This corresponds to the concentration of fc-"ih*, FJ" ppm, which is an acceptable value in terms of safety standards such as the working environment. However, in some cases, the local concentration may become extremely high, so it is necessary to suppress the generation of hydrogen cyanide as much as possible during thermal decomposition of TCNQ salt. The purpose of the present invention is to provide an organic semiconductor composition in which the generation of hydrogen cyanide during thermal decomposition is suppressed by adding a polyhydric alcohol and a paraffin hydrocarbon to an organic semiconductor consisting of the following.

Means for Solving the Problems The basic composition of the organic semiconductor composition according to the present invention is that TCNQ salt obtained by a known method is pulverized and polyhydric alcohol and paraffin hydrocarbon are uniformly mixed as additives. . Alternatively, a polyhydric alcohol and a paraffin hydrocarbon can be heated and impregnated into the TO)IQ salt powder. The organic semiconductor to which the present invention is applied mainly has TCNQ as one component (acceptor), and other components include metal ions ((e.g., Ll, Ha, K, Os).
.

Ba', Ca+, Cu+, (iu+, etc.), ammonium.

Pyridinium, quinolinium, zenadinium.

Organic semiconductors consisting of acridinium, phenothiazinium, tetrathiafulverenium, tetraselenafulvalenium and substituted products thereof, but with acceptors having other nitrile groups, such as dicyanodichlorovaraquinone, tetracyanoethylene, tetracyano It is also possible to use naphthoquinone and the like.

Function The organic semiconductor composition disclosed in the present invention is a mixed system consisting of the above-mentioned organic semiconductor, polyhydric alcohol, and paraffin hydrocarbon, and these two types of additives exhibit a synergistic effect to thermally decompose the organic semiconductor. The effect of suppressing the generation of hydrogen cyanide during heating has been clarified through many thermal decomposition experiments and analyzes of generated gas. As described above, the materials were selected based on an empirical method, and the hydrogen cyanide generation suppressing effect of these additives is expected to be due to the following several reasons.

It is thought that when TCNQ salt thermally decomposes, some radical R is released from the molecule, which induces a chain reaction and causes rapid exothermic decomposition.

It is believed that the polyhydric alcohol and paraffin hydrocarbon disclosed in the present invention trap such radicals, act as a stopper for chain reactions during combustion or oxidation, and suppress the decomposition of TCNQ. In addition, polyhydric alcohols seem to have the effect of liberating hydroxyl groups, extracting hydrogen from organic semiconductors, and promoting carbonization of the organic semiconductors. Furthermore, since paraffin hydrocarbons melt at a temperature sufficiently lower than the decomposition temperature of organic semiconductors (nearly 280'C), it is also possible that the products cover the organic semiconductors and prevent gas release. It will be done. In this way, compared to using polyhydric alcohol or paraffin hydrocarbon alone, the effects of both additives seem to work synergistically to suppress HCN gas generation, giving better results.

For the above reasons, it is desirable that the polyhydric alcohol has as many hydroxyl groups as possible in one molecule. or,
It is more effective to melt the organic semiconductor as quickly as possible than to decompose it, but from the viewpoint of thermal stability of an electric element using an organic semiconductor, a material with as high an axis point as possible should be used. Therefore, in the present invention, polyhydric alcohols include pentaerythritol (melting point: 260°C), sorbitol (melting point: 100°C), paraffin hydrocarbons include solid paraffin (melting point: 0°C), and low molecular weight polyethylene (melting point: approximately 120°C). C) was used. The amount of additives added is effective if the total amount of both polyhydric alcohol and paraffin hydrocarbon is 3 parts by weight or more per 100 parts by weight of the organic semiconductor, and the ratio of polyhydric alcohol and paraffin hydrocarbon is The effect was greatest when the additive was added in equal parts. The total amount of additives is essentially arbitrary, and a larger amount is desirable in order to suppress the generation of HCN gas, but TC
The amount should not exceed 120 parts by weight (total amount of the two additives), which may impair the semiconductor properties of the NQ salt.
1 is desirable. That is, it is desirable that the amount of polyhydric alcohol be 3 to 60 parts and the amount of paraffin hydrocarbon be 2 to 60 parts.

Example Examples of the present invention will be described below.

N-n-butylisoquinolinicum (T
Using 2100 parts by weight of CNQ), various polyhydric alcohols and paraffin hydrocarbons were added in appropriate amounts, and after mixing and kneading well in a mortar, the mixture was sealed in a glass tube with air.
It was heated at 300°C for about 10 minutes. When the temperature of the glass tube reached 300"C, the organic semiconductor melted and then decomposed after 10 to 60 seconds. In some cases, the glass tube burst at the same time as the decomposition, but after decomposition, the generated gas was transferred to other glass. The amount of HCN generated was measured using gas chromatography, a north-side gas detection tube, and JIS K109 method.

The table below shows H of compositions with various paraffin hydrocarbons added.
The data on the amount of CN generation is shown.

(Left below) As shown above, adding 3 parts by weight or more of both polyhydric alcohol and paraffin hydrocarbon is effective in suppressing HCN gas generation, and the effect becomes more significant as the amount added increases. . In particular, when polyhydric alcohol and paraffin hydrocarbon are added in equal amounts, when both are added in equal amounts,
I found it to be the most effective.

Effects of the Invention As described above, the present invention provides the ionic radical salt 1 of TCNQ.
By adding a total of 3 parts by weight or more of polyhydric alcohol and paraffin hydrocarbon to 00 parts by weight, it is possible to suppress the generation of toxic gases, especially hydrogen cyanide, during thermal decomposition or combustion. If used, the safety of electronic devices using TCNQ salt, such as temperature sensors, electrolytic capacitors, and conductive films, will be significantly improved.

Claims (4)

[Claims] (1) The ionic radical salt of 7,7,8,8-tetracyanoquinodimethane contains an additive consisting of a polyhydric alcohol and a paraffin hydrocarbon, and the ionic radical salt 100
An organic semiconductor composition characterized in that an additive is added in an amount of 3 parts by weight or more based on parts by weight. (2) 100 parts by weight of ionic radical salt, 3 to 60 parts by weight of polyhydric alcohol, and 2 to 6 parts by weight of paraffin hydrocarbon.
The organic semiconductor composition according to claim 1, characterized in that it contains 0 parts by weight. (3) The organic semiconductor composition according to claim 1, wherein the polyhydric alcohol is any one of pentaerythritol, erythritol, sorbitol, mannitol, and glycose. (4) The organic semiconductor composition according to claim 1, wherein the paraffin hydrocarbon is solid paraffin or low molecular weight polyethylene.