JPS63154397A - Ic card - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Rimi Ni Tachitan Plate±! The present invention relates to an IC card having a novel insulating layer. More specifically, the insulating filler is a copolymer comprising at least two types of units derived from ethylene and units derived from heptamer having a polar group, or a crosslinked product of a mixture of these copolymers and an epoxy resin. This invention relates to an IC card characterized in that the insulating filler is a surface plate.

To provide an IC card that not only has a good adhesive layer with internal prints, etc., but also has excellent insulation and water resistance, and also has good elasticity, so that it has excellent durability and impact resistance. The purpose is to

As stated in "Great Encyclopedia °° (Kodansha, published in 1982), supervised by Tadao Umesao et al., pages 86 to 87,
IC cards such as cash cards, credit cards, and other cards with built-in microcomputers are in circulation and widely used in daily life, ranging from cards with only built-in memory to IC cards with built-in integrated circuits such as semiconductor memory. Development is underway. For example, it consists of an IC that controls writing and reading of information, and a storage capacity (IC) that can be read, written, and erased.

These IC cards also follow the trend of worldwide usage and international standards are being created. The size is 5.4 in height.
cm, width 8.50cm, thickness 0.68~0.80■ (
Currently, 1.5 to 5 am) is being considered.

The key point is how many functions, ie, storage capacity, can be provided within this fixed-sized IC card.

However, these IC cards not only embed an IC with a large storage capacity, but also require mounting of the IC.

It must also have a built-in power connection and display, and
Fraud identification and counterfeit prevention capabilities are also required. Further, since the built-in integrated memory is susceptible to static electricity, noise such as discharge from clothing or contact with metal pieces may cause malfunction or even destruction of the IC.

Today's IC cards range from simply housing a printed circuit board containing an IC in a thermoplastic case to having electromagnetic and static shielding on the front and back sides, as well as aluminum and steel that also serve as bending reinforcements.

Some use thin plates of metal such as diatom steel and stainless steel. Using such metal thin plates on both the front and back surfaces provides a reinforcing effect and a shielding effect, but the insulation of IC and chip components mounted on the board poses a problem. IC
If you push the card locally, there may be problems such as contact between the internal circuit and the metal surface, causing a short circuit, damage to the connections between the chip components, or destruction of the components themselves. There is.

Currently, in order to prevent these problems, insulating double-sided tape is used for insulation, and adhesive strength is also used to fix the board to the card. However, the IC card itself has a connector, and when it is used, it is repeatedly inserted and removed to connect it to a computer, which causes the double-sided tape to slip. Furthermore, since there is a space between the front and back surfaces of the IC card due to the unevenness of the parts, there are drawbacks such as susceptibility to deformation due to external forces such as warping. Furthermore, since IC cards will be carried around at all times in the future, durability under high temperature and high humidity will become an issue.

From the second point, the present invention does not have these drawbacks (problems); in other words, the insulating filler has good adhesion to the metal plates and printed wiring boards used for the front and back plates of the card. Not only does it have good insulation properties, it also has good heat resistance and water resistance, and it can also fill in the spaces between the skin layer and the unevenness caused by parts such as various printed wiring boards. The object of the present invention is to obtain an IC card that can be stably used for a long period of time because it has a function of absorbing shocks expected in the future.

According to the present invention, these problems can be solved by at least the insulating filler in the IC card containing (A) units derived from at least ethylene and α,β-unsaturated monocarboxylic acid, α, Copolymer (I) consisting of a unit derived from at least one type of heptamer selected from the group consisting of β-unsaturated dicarboxylic acid, its anhydride and Hafester; and (B) a copolymer comprising at least a unit derived from ethylene and an epoxy A copolymer (H
) or a crosslinked product of a mixture consisting of these copolymers and (C) an epoxy resin having at least two epoxy groups in one molecule, and the mixing ratio of copolymer (I) in the mixture is 10 to 90. % by weight, and the ratio of the sum of carboxyl groups and carboxylic anhydride groups to the sum of epoxy groups in the mixture is from 0.2/1 to 5/1 in molar ratio. , can be solved by. The present invention will be explained in detail below.

The copolymer (I) used in the present invention has at least units derived from ethylene and is selected from the group consisting of α, β-unsaturated monocarboxylic acids, α, β-unsaturated dicarboxylic acids, their anhydrides, and halfesters. It is a copolymer consisting of units derived from at least one type of heptamer. Examples of the copolymer include the following polymers.

(Copolymer of ethylene and α, β-unsaturated monocarboxylic acid [hereinafter referred to as “ethylene copolymer (a)”]) (2) Copolymer of ethylene and α, β-, β-monocarboxylic acid ester A copolymer obtained by saponifying part or all of the copolymer and performing a neutralization reaction such as demetallization using an acid etc. [hereinafter referred to as "ethylene copolymer (b)"] )] and (3) copolymers of ethylene and α, β-unsaturated dicarboxylic acids, their anhydrides, or their halfesters [hereinafter referred to as [
These copolymers (I) are preferably those that melt at a temperature of 150° C. or lower and have fluidity.

(A) Ethylene copolymer (a) Ethylene copolymer (a) contains at least ethylene and α,
It is a β-unsaturated unsaturated monocarboxylic polymer, which is copolymerized with a radically polymerizable comonomer having a polar group (hereinafter referred to as the "third component") in order to ensure the above-mentioned fluidity properties. is preferred.

By copolymerizing this third component as a comonomer, a multi-component copolymer having units derived from a heptama corresponding to the third component copolymerized into the ethylene copolymer (a) can be obtained. The same applies to the ethylene copolymers (b) to ethylene copolymers (d) described later].

The number of α,β-unsaturated monocarboxylic acids that can be used in the production of the ethylene copolymer (a) is generally 3 to 20, with 3 to 10 being particularly desirable. acrylic acid.

Methacrylic acid, crotonic acid, hepta-alkyl maleate,
Examples include heptanoalkyl fumarate.

Further, the third component is a radically polymerizable vinyl compound containing a polar group, and representative examples include unsaturated carboxylic acid esters, vinyl esters, and alkoxyalkyl (meth)acrylates.

The number of carbon atoms in the unsaturated carboxylic acid ester is usually 4 to 40, and 4 to 20 carbon atoms are particularly preferred. Representative examples include carbon atoms with good thermal stability such as methyl (meth)acrylate and ethyl (meth)acrylate. Those with poor thermal stability such as t-butyl (meth)acrylate are not preferred because they cause foaming.

Furthermore, the number of carbon atoms in the alkoxyalkyl (meth)acrylate is usually at most 20 (1!i).Also, it is preferable that the alkyl group has 1 to 8 carbon atoms (preferably 1 to 4 carbon atoms), Furthermore, the number of carbon atoms in the alkoxy group is 1 to 8 (
Representative examples of preferred alkoxy(meth)alkyl acrylates, preferably 1 to 4 alkoxy(meth)alkyl acrylates, include methoxyethyl acrylate, methoxyethyl acrylate, and butkiethyl acrylate. Furthermore, the number of carbon atoms in vinyl ester is generally at most 2.
Typical examples thereof include vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl bivalate.

In the ethylene copolymer (a), the amount of the third component is 2
It is preferably 5 mol% or less, and particularly preferably 2 to 20 mol%. Even if it exceeds 25 mol%, the characteristics of the present invention are expressed, but it is not necessary to exceed 25 mol%, and from the viewpoint of production and economy. It's not consistent.

α, β-unsaturated unsaturated monocarboxyrene copolymer (
The amount of bonding in a) is preferably 0.5 mol% or more and 25 mol% or less, particularly 1.0 mol% to 15 mol%.
Mol% is preferred. Although block or random copolymers are available, random copolymers are particularly preferred.

The α,β-unsaturated monocarboxylic acid is used as a crosslinking reaction point with the ethylene copolymer (d) described later and the epoxy resin, and to provide adhesiveness with a wide variety of base materials. There is no need to be excessive in terms of
If the amount increases, the water absorption will increase, which will not only have a negative impact on the deterioration of electrical properties due to foaming during molding and water absorption after molding, but will also cause manufacturing problems such as safety and minute recovery, as well as economic problems. On the other hand, it is disadvantageous and undesirable.
If it is less than 0.5 mol %, there will be no problem in terms of adhesiveness, but it is not preferable because it will be insufficient in terms of heat resistance.

(B) Ethylene copolymer (b) Furthermore, the ethylene copolymer (b) used in the present invention is one of the ester groups in the ethylene copolymer consisting of ethylene and an unsaturated carboxylic acid ester. It is a copolymer obtained by saponifying part or all of it and performing a neutralization reaction such as demetalization treatment.

The number of carbon atoms in the unsaturated carboxylic acid ester is usually 4 to 40, and 4 to 20 carbon atoms are particularly preferred. Typical examples include methyl (meth)acrylate, ethyl (meth)acrylate, and isopropyl (meth)acrylate. , n-
Examples include butyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, diethyl fumarate, and the like.

The content of unsaturated carboxylic acid ester in the ethylene copolymer (b) is preferably 1 to 25 mol%. The conversion rate, calculated as carboxylic acid-containing units in the copolymer after neutralization, is preferably 0.5 to 20 mol%, particularly preferably 1 to 15 mol%.

The saponification reaction can be carried out using a widely known method, for example, using a mixed solvent of toluene and isobutyl alcohol (mixing ratio: 50
: 50) by adding NaOH and a copolymer containing an ester group and refluxing for 3 hours. The saponification rate can be arbitrarily adjusted by adjusting the amount of NaOH. Furthermore, this saponified product is precipitated with water or alcohol, and after filtering the solvent, it is vacuum-dried at 50° C. day and night. Disperse this polymer in water.

Ethylene copolymer (b) is obtained by adding sulfuric acid to this and stirring at 70° C. for 1 hour to perform a neutralization reaction for demetallization.

(C) Ethylene copolymer (C) Also, the ethylene copolymer (C) used in the present invention
) may result in a copolymer of ethylene and an α,β-unsaturated dicarboxylic acid, its anhydride, or its monoester (which may also contain the third component),
That is, it is a direct copolymerization of ethylene, α,β-unsaturated dicarboxylic acid, its anhydride or its halfester, or these and the third component.

The third component is the same as the ethylene copolymer (a). The same types of compounds can be mentioned.

When the ethylene copolymer (C) is produced by a direct copolymerization method, α,β-unsaturated dicarboxylic acid, its anhydride, or its halfester is selected as the comonomer.

The α,β-unsaturated dicarboxylic acid usually has at most 20 carbon atoms, preferably 4 to 16 carbon atoms. Typical examples of the dicarboxylic acids include maleic acid,
Examples include fumaric acid, itaconic acid, citraconic acid, and 3,6-nindomethylene-1,2,3,8-tetrahydro-cis-phthalic acid (nadic acid 0).

As α,β-unsaturated dicarboxylic acid hafester,
The number of carbon atoms is generally at most 40.

In particular, 5 to 20 items may be mentioned. A typical example thereof is one in which one of the carboxyl groups of the dicarboxylic acid is halfesterified with a representative example of an alcohol described below. Representative examples of the alcohol include some alcohols having at most 20 carbon atoms, such as methanol, ethanol, propatool, and butanol. Representative examples of Hafestel include maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monoisopropyl ester, maleic acid monomethyl ester, and itaconic acid monoethyl ester.

The bond amount of "α,β-unsaturated dicarboxylic acid or its halfester" (hereinafter referred to as "unsaturated dicarboxylic acid component") in the copolymer (c) is 0.5 mol% or more and 20 mol% or less. It is preferable that there be the following, more particularly: 1.
It is 0 to 15 mol%.

The copolymer (II) used in the present invention is an ethylene copolymer [hereinafter referred to as "ethylene copolymer It is called "combination (d)".

(D) Ethylene copolymer (d) The ethylene copolymer (d) contains at least ethylene and "
It is a copolymer with an unsaturated compound having an epoxy group capable of radical copolymerization (hereinafter referred to as an "epoxy compound"). Furthermore, a multicomponent copolymer obtained by copolymerizing ethylene and an epoxy compound with the third component can also be used for the same reason as above.

Representative examples of this epoxy compound include those whose general formulas are represented by the following formulas [Formula (1) and Formula (II)].

CH2=CR4 Typical examples of epoxy compounds represented by formulas (I) and (n) include glycidyl methacrylate, glycidyl acrylate, α-methylglycidyl acrylate, α-methylglycidyl methacrylate, vinyl glycidyl ether, and allylglycidyl. Examples include ether and methallyl glycidyl ether.

Ethylene and unsaturated carboxylic acid used to produce these ethylene copolymers (a), ethylene copolymers (C), ethylene copolymers (d), and ethylene copolymers (b) Copolymer with ester is 100
~2500Kg/crn' ultra-high pressure, 120~
It can be produced by radical polymerization using a free radical generator such as peroxide at a temperature of 260°C, optionally using a chain transfer agent, in an autoclave equipped with a stirrer or a tubular reactor. Methods for producing these copolymers are well known.

The melt index (JIS K-
7210, temperature is 190℃ and load force 2,
16Kg TeIN constant, hereinafter rM, 1. J) are usually 0.5 g/10 minutes or more, and 5.0
g / 10 minutes or more is desirable, especially 50 g
/ 10 minutes or more is suitable.

The mixture of the present invention comprises copolymer (I) and copolymer (II).
) can be produced by uniformly mixing them at the mixing ratios described below, and the fluidity of the mixture can be improved by mixing them with the epoxy resins described below.

Furthermore, the copolymer (I) is a copolymer consisting of units derived from ethylene and units derived from α,β-unsaturated dicarboxylic acid anhydride, that is, an anhydride of ethylene and α,β-unsaturated dicarboxylic acid. Or when using an ethylene-based multi-component copolymer consisting of these and the third component, "an organic compound or polymer having a boiling point of 150°C or higher,
and having hydroxyl 2G (-oH group) or carboxyl group (-C0OH group) (hereinafter referred to as "organic compound or polymer"), the copolymer (I) and Promote crosslinking with polymer (II).

(E) Epoxy resin The epoxy resin used in the present invention has at least two epoxy groups in one molecule. Generally, the softening temperature indicated by the Durand method is 170°C or lower, preferably 180°C or lower. If an epoxy resin whose softening temperature exceeds 170'O is used, a reaction will occur during mixing in the molten state, making it impossible to obtain a homogeneous mixture.

For more information on this epoxy resin, please refer to 'Encyclopedia Off Polymer Science and Technology (
Ensyelopedia of Po17merSc
Interscience Publishers, Inc. (Division Off John Wiley & Sons, Inc.) (In
terscie-nce Publisher div
ision of John Wile2 & 5on
sInc, ), published in 1987], Volume 6, No. 20
Pages 9 to 271, edited by Shunsuke Muratachi, Ryohei Oda, and Minoru Iki, “Plastic Handbook” (Breakfast Shoten, published February 1980), pages 272 to 2111, edited by Hiroshi Kakiuchi, “Epoxy Resin” (Shoaki) The manufacturing method, softening, uses, etc. are described on pages 89 to 105 (published in June 1978).

Examples of this epoxy resin include a reaction product between an active hydrogen compound (e.g., bisphenol A) and epichlorohydrin, a reaction product between a novolac resin and epichlorohydrin, a reaction product between an oxycarboxylic acid (e.g., oxybenzoic acid) and epichlorohydrin, and a reaction product between a polyphenol and epichlorohydrin. Reaction products with epichlorohydrin, resorcinol-acetone resins with epichlorohydrin, polyhydric phenols with epichlorohydrin, aromatic carboxylic acids with epichlorohydrin, alicyclic hydrocarbons (e.g. cyclohexene, dicyclopenta Examples include epoxy resins obtained by oxidizing gen, cyclopentene).

(F) Organic compound or polymer Among the organic compounds or polymers, examples of the polymer include the ethylene copolymer (a), ethylene copolymer (b), and ethylene copolymer (c). Units derived from ethylene and α, β-unsaturated monocarboxylic acid, α
, a copolymer with a unit derived from a monomer selected from the group consisting of β-unsaturated dicarboxylic acid and its halfester (these copolymers may be ethylene-based multicomponent copolymers containing a third component) , saponified copolymers of ethylene and vinyl acetate, copolymers of ethylene and hydroxyalkyl (meth)acrylates, and polymers (including homopolymers) whose main components are ethylene or propylene. Obtained by graft polymerization of the α, β-unsaturated monocarboxylic acid, α, β-unsaturated dicarboxylic acid, or anhydride thereof used in producing the polymer (a) and the ethylene copolymer (c). Examples include modified olefin polymers. Furthermore, examples of organic compounds include ethylene glycol, polyethylene glycol, propylene glycol, glycerin, and polypropylene glycol.

(G) Mixing ratio The mixing ratio of the ethylene copolymers (a) to ethylene copolymers (c) in the mixture of the present invention is 10 to 80% by weight as their total amount, and 15 to 90% by weight. is preferred, particularly 20 to 85% by weight.

The mixing ratio of the ethylene copolymer (a) to the ethylene copolymer (c) in the mixture is 10 as the total amount of 5.
Even if it is less than 30% by weight or exceeds 30% by weight, the crosslinking properties of the mixture may be insufficient depending on the composition ratio, and the resulting crosslinked product may have poor heat resistance. The mixing ratio of the epoxy resin is at most 50% by weight, preferably 40% by weight or less, particularly preferably 30% by weight or less. If the proportion of the epoxy resin in the mixture exceeds 50% by weight, the resulting crosslinked product will have poor flexibility.

In addition, the carboxyl group (-cooH) of the ethylene copolymer (a) to ethylene copolymer (C) in the mixture
The ratio of the sum of the carboxylic acid anhydride groups to the sum of the epoxy of the ethylene copolymer (d) and the epoxy resin is from 0°2/1 to 5/1, and from 0.3/1 to 3/I. Preferably, 0.5/1 to 2/1 is particularly suitable. The ratio of the sum of carboxyl groups and carboxylic acid anhydride groups to the sum of epoxy groups in the mixture is 0.2/
Whether it is less than 1 or more than 5/1, the adhesion to metals at high temperatures is poor.

In producing the mixture of the present invention, when blending the above-mentioned organic compounds or polymers, the mixing ratio thereof should be the sum of the above-mentioned copolymer (D and copolymer (II) or these copolymers and the epoxy resin). Usually at most 20 parts by weight per 100 parts by weight, preferably from 0.1 to 20 parts by weight, preferably from 0.5 to 20 parts by weight, especially preferably from 1.0 to 15 parts by weight. .

(H) Mixing method In order to produce the mixture of the present invention, the above “copolymer (I
) [i.e., selected from ethylene copolymer (a), ethylene copolymer (b) and ethylene copolymer (C)] and copolymer (■) [i.e., ethylene copolymer ( d)] or copolymers thereof and epoxy resins and/or organic compounds or polymers” (
(hereinafter referred to as "mixed components") may be uniformly mixed.
At this time, the thermal conductivity is l X I 0-3cal/”C
j・Cmaro・second position and electrical resistance value is 1010Ω
- Thermal conductivity can be improved when the crosslinked thin material obtained by blending an inorganic filler with a particle size of C■ or more is relatively thin.

Representative examples of such inorganic fillers include beryllium oxide, boron nitrogen, magnesium oxide (magnesia), aminium oxide (alumina), silicon carbide, and glass beads. Furthermore, the particle size of the inorganic filler powder is preferably 100 JLm or less, particularly preferably 0.1 to 20 gm.
If the layer is less than μ layer, it is difficult to uniformly disperse it in the mixed components. On the other hand, if it exceeds longm, the thickness of the cross-linked material layer (layer of insulating filler material) becomes thick and the adhesive strength further decreases, which is not desirable.

The blending ratio of this inorganic filler is at most 70% by volume.

The mixing method may be tri-blending using a mixer such as a Henschel mixer, which is commonly used in the field of olefin polymers, or melt-kneading using a mixer such as a Banbury, ° extruder, or roll mill. can be given. At this time, a more uniform mixture can be obtained by triblending in advance and melt-kneading the resulting mixture. When melt-crosslinking, it is necessary that the mixed components do not undergo a substantial crosslinking reaction (if crosslinking occurs, not only will the moldability deteriorate when the resulting mixture is molded as described below),
(This is undesirable because it may cause a decrease in the shape of the intended molded product or in the heat resistance when crosslinking the molded product.)
From this, the melt-kneading temperature depends on the type and viscosity of the ethylene polymer and epoxy resin used, but is preferably room temperature (20°C) to 150°C.
C or lower is suitable.

As a measure of "substantially no crosslinking", the total amount of copolymer (1), copolymer (II), and epoxy resin is "extracted in boiling toluene for 3 hours, and then the diameter is 0. In general, it is preferable that the amount of "extracted scent" (hereinafter referred to as "extracted scent") is 15% by weight or less, and
The content is preferably 0% by weight or less, and most preferably 5% by weight or less.

When using the mixture obtained as described above for manufacturing IC cards, this mixture may be used as it is, and T
- Films or sheets may be produced and used by the Gouy method or the inflation method. In this case, when extrusion is carried out at high temperatures, some or all of the films or sheets may be crosslinked.

Therefore, the extrusion strength is usually 250°C or less.

(J) IC card and its manufacturing method The IC card of the present invention can be manufactured by heat-pressing and laminating the peripheral materials described later and the mixture described above as described later. At this time, it is important that the mixture is crosslinked by heating as described below.

Hereinafter, representative examples of the IC card of the present invention will be explained with reference to the drawings.

FIG. 1 is a partially enlarged sectional view of a representative example of the IC card of the present invention. The IC card shown in this drawing includes a skin layer 1, resin (crosslinked mixture) layers 2 and 2°, an IC chip 4, and a printed wiring board 3 on which other chip components 5 are mounted (through holes 6, solder connections). It is laminated by part 7). FIG. 1 is a typical partially enlarged cross-sectional view of an IC card using the resin layer of the present invention. It goes without saying that it is possible to use it in ways that take advantage of its heat resistance and water resistance.

(K) Peripheral Materials The following materials can be used to effectively utilize the present invention.

The skin layers (front and back plates) indicated by 1 in Figure 1 are used for reinforcement, such as acrylonitrile-butadiene-styrene terpolymer (ABS resin),
Thermoplastic resins such as polyphenylene oxide (PPO resin), polyamide resin, polycarbonate (PC), and polyester are commonly used, or thermosetting resins such as phenol resin, unsaturated polyester resin, and epoxy resin are used, but this When crosslinking the mixture that is the insulating filler of the invention, those having sufficient heat resistance to reach the crosslinking temperature described below are preferably used.

On the other hand, foils or plates of metals such as aluminum, silicon steel, iron, and copper are useful for shielding electromagnetic waves, magnetism, and static electricity.

When a thermoplastic resin or a thermosetting resin is used, the thickness is usually 30 gm to lam, preferably 50 gm IIa to lam, and particularly preferably 1002 rs to lam. Further, when a metal foil or plate is used, its thickness is generally 10 m to 0.8 m, preferably 1Qp-m to 0.81 m, and particularly preferably 507 m to 0.6 µs. be. Whether it is a thermoplastic resin, a thermosetting resin, or a metal, if the thickness is less than the lower limit, the reinforcing effect will be reduced. On the other hand, if the upper limit is exceeded, the overall thickness will increase, which is undesirable. (for example, thermoplastic resin and metal), and both sides may have the same or different thicknesses.

Further, as the printed wiring board, any commercially available printed wiring board can be used. Typical examples of printed wiring boards include thermosetting resin substrates such as paper-phenol substrates and glass-epoxy substrates, substrates based on metals such as aluminum, iron, and copper, and hybrid ceramic substrates (mainly, Examples include flexible wiring boards using alumina substrates) and heat-resistant thermoplastic resins (eg, polyimide resins, saturated polyester resins). These printed wiring boards and flexible wiring boards may be provided with a coverlay.

Alternatively, silicone resin or epoxy resin may be made into a pot shape in advance to protect the surface of the IC chip (4 in FIG. 1).

(L) Heat-press bonding method As shown in Figure 1, the mixture of the present invention or a pre-formed essentially non-crosslinked mixture is placed between the image surface layer of the IC card of the present invention and the printed wiring board. By filling and laminating films or sheets, I
C cards can be manufactured. As for the lamination method,
The method is selected depending on the thickness of each part or calendar, ease of manufacture, productivity, etc., but generally there are a hot press method using a press molding machine and a method of laminating while applying pressure using a hot roll. In addition to this, the mixture or film or sheet can be filled between the image skin layer and the printed wiring board by applying commonly used methods such as pot molding, transfer molding, and injection molding.

In the heat press method, a product with sufficient adhesiveness can be obtained at a heating temperature of 30°C or higher, but if heat resistance is required, the temperature must be as high as possible (usually 120 to 300°C) without damaging the IC parts. It is preferable to press the bond at a temperature of 0.5 to
It is necessary to press the mixture for IO minutes, and a crosslinking reaction occurs within the resin (polymer) of the mixture or film or sheet, and the adhesiveness between the crosslinked product and the skin layer, printed wiring board, IC chip, and other parts is improved. and heat resistance is significantly improved.

The pressurizing conditions may be within a range that does not move or destroy the IC chip or other parts, and is generally 0.1 to 100.
Kg/cm'' (gauge pressure).Furthermore, in order to achieve uniform adhesion and to prevent the inclusion of air bubbles, it is particularly desirable to apply pressure under reduced pressure with a slight load.

When using the mixture of the present invention as an uncrosslinked film or sheet, holes are punched out in advance at locations corresponding to IC chips and other convex parts. film or sheet,
Printed wiring boards and the like can be laminated in advance and then hot-pressed and bonded and cross-linked as described above. Rather, this method is preferable because it allows IC chips and various parts to be molded without stress being applied during stacking.

The residual content after extraction of the crosslinked insulating filler of this invention is at least 60%, preferably 65% or more, and especially 70% or more, which has excellent heat resistance and water resistance. It is suitable for

The present invention will now be described in more detail with reference to Examples.

In addition, in the examples and comparative examples, "peel strength" is J
In accordance with IS C8481, 3 cm of the crosslinked material (insulating filler) and skin layer were left, the rest was removed by etching, and the peel strength was measured when the skin layer was peeled off at 90 degrees (pulling speed 50 mm/min). .

Note that the mixtures used in the Examples and Comparative Examples were manufactured as follows.

Ethylene-acrylic acid copolymer (density 0.954 g/cr
n', copolymerization ratio of acrylic acid 20% by weight, hereinafter referred to as rEAAJ) and M, 1. terpolymer of ethylene-methyl methacrylate-glycidyl methacrylate (copolymerization ratio of methyl methacrylate 18.6% by weight, copolymerization ratio of glycidyl methacrylate 12.7% by weight, hereinafter r GMAJ ) [mixture ratio EAA/GMA=
50150 <weight ratio), hereinafter referred to as "mixture (I)"), M, 1. is 210 g/10 min.
Maleic anhydride-ethyl acrylate terpolymer (maleic anhydride copolymerization ratio 2.6 mol%, ethyl acrylate copolymerization ratio 9.5 mol%, hereinafter r ETP
J) and the GMA [mixture ratio F
TP/GMA=Go/40 (weight ratio), hereinafter referred to as "mixture (II) J" and the above ETP and GMA
and epoxy resin (manufactured by Ciba Geigy, trade name: Araldite ECN-1298, epoxy equivalent: 235
g/aq, Duran melting point 88℃, below r ECH
(referred to as J) [mixture ratio ETP/GM
A/EC)I=50/45/5 (weight ratio), hereinafter referred to as "mixture (■)"] were prepared by tri-blending them for 5 minutes using a Henschel mixer.

Examples 1-7. Comparative Example 1.2 Mixture (1) or mixture (m
) as well as the E used to prepare these mixtures.
AA and GMA were each extruded with a T-die (
Diameter 40mm, die width 100I, rotation speed 85
rotations/min) with a thickness of 500 g rr+
and too 4 m of film were formed. The molding temperature is cylinder Ct”100°C, c2=120°C,
The test was carried out at a die temperature of 140° C., and a film free from gelation and foaming was obtained. Note that if the cylinder temperature is 120°C or higher and the die temperature is 200°C or higher, the mixture (
In each of I) to mixture (III), a large amount of gel was generated, and a good film could not be obtained. The extraction residue of each of the obtained films was 15% or less.

The film with a thickness of 5004 m obtained was made to be 2° in Fig. 1, and the film with a thickness of +004 wr was made to be 2° in Fig. 1. (each type and thickness are shown in Table 1) and printed wiring board (glass, poxy resin base, 0.51 thickness, double-sided board with through holes, 3 IC chips, 2 capacitors) and 5 resistors) are stacked as shown in Figure 1, and 180
Adhesive crosslinking was carried out for 20 minutes in a vacuum press set at addition].

The peel strength between the surface plate and the film was measured from the obtained laminate (IC card) having a width of 54 s+s, a length of 88 m5, and a thickness of 262 to 3.5 H. The results are shown in Table 1. Next, the extracted afterflame of the crosslinked products of these mixtures was measured. The results are shown in Table 1. In all Examples, the extracted afterflame was 80% or more. In addition, to examine heat resistance, each IC card was observed after being immersed in a 280°C solder bath for 1 minute. Although no change was observed in any of the Examples, the resin layer flowed out in both Comparative Examples 1 and 2. In addition, the mixtures used in Examples 6 and 7 were pressed under the same conditions.

Volume resistivity of each flat plate (JIS KEt91K
The dielectric constant (IM), dielectric loss tangent, and withstand voltage were measured. The volume resistivity of both is 1016
Ω·C11, and the dielectric constant was 2.5. Further, the dielectric loss tangent was 0.02, and the withstand voltage was 113 KV/am.

(Left below) From the following results, the cross-linked product which is a constituent component of the present invention is IC.
When used as an inner layer material for cards, it not only has good adhesion with the skin layer (front plate and back plate), but also has excellent heat resistance and electrical insulation, and can densely fill the circuit board and the skin layer. It is clear that it is resistant to external shocks and has improved durability.

The IC card of the present invention not only has good heat resistance of the crosslinked mixture filled therein, but also has significantly improved electrical insulation. Moreover, since the mixture has a crosslinking ability, it has elasticity, and since the crosslinked product has adhesive properties, a durable product can be obtained, and the following effects are exhibited.

There is no damage to circuit parts due to shrinkage during curing, and no damage to circuits or parts due to moisture absorption.Also, since it is a crosslinked material, it has high elasticity, so it does not cause partial peeling or cracking when exposed to external impact. There is no such thing.

(2) Since the cross-linked material has excellent electrical properties (e.g. insulation, withstand voltage, dielectric loss tangent), even if a conductive metal layer is used as a shield on the surface layer, the IC card may be slightly bent. Even if such deformation occurs, the circuit section will not be short-circuited or destroyed.

(3) Not only does it have excellent heat resistance and water resistance, but it also prevents adhesive from leaking out when fixing metal plates or thermosetting resin-based printed wiring boards to the surface material. There is no decrease in adhesive strength due to deterioration.

(4) By filling the crosslinked mixture, each component is fixed and the durability of the IC card is improved.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view of a typical example of an IC card. 1... Epidermal layer (front plate, back plate) 2.2°...
...Crosslinked mixture (resin layer) 3...Commercially available printed wiring board 4...IC chip, 5...Chip component 6... Through hole part

Claims (1)

[Claims] At least the insulating filler in the IC card is selected from the group consisting of (A) units derived from at least ethylene, α, β-unsaturated monocarboxylic acids, α, β-unsaturated dicarboxylic acids, anhydrides and half esters thereof; A copolymer consisting of units derived from at least one monomer (I
) and (B) a copolymer (II) consisting of at least a unit derived from ethylene and a unit derived from an ethylenically unsaturated monomer containing an epoxy group, or a copolymer of these and (C) an epoxy group in one molecule. It is a crosslinked product of a mixture of epoxy resins having at least two groups, the proportion of the copolymer (I) in the mixture is 10 to 90% by weight, and the amount of carboxyl groups and carboxylic anhydride in the mixture is 10 to 90% by weight. An IC card characterized in that the molar ratio between the sum of physical groups and the sum of epoxy groups is from 0.2/1 to 5/1.