JP2000007751A - Card base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new biodegradable card base material. SOLUTION: This base material is prepared by molding a polymer which mainly comprises a polymer of a polyester diol having a repeating structure of the formula (wherein R is a 2-12C hydrocarbon group; and n is an integer of 2 or larger) and 2,5- and/or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane. Preferably, the molecular weight of the polyester diol having the repeating structure of the formula is 50,000 or larger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a card base material. Specifically, general formula (1)

Embedded image (Wherein, R is a hydrocarbon group having 2 to 12 carbon atoms, and n is an integer of 2 or more) and 2,5- and / or 2,6-
The present invention relates to a card base obtained by molding a polymer mainly composed of a polymer with diisocyanatomethylbicyclo [2,2,1] heptane.

[0002]

2. Description of the Related Art Currently, cards include ID cards for proof of identity, membership cards, cash cards having a monetary value, credit cards, and the like.
It is used in a wide range of fields as prepaid cards, commuter passes, and toll passes. In particular, as a card that has been used most frequently, there is a so-called prepaid card in which a fixed amount of money is paid in advance and value information corresponding to the amount is recorded.

[0003] In this card, value information and identification information are printed or printed on a card base via a reading / writing device as picture / character information, or a magnetic recording unit or an optical recording unit provided on the card base. Since the information is recorded as mechanical read information in a section, mechanical characteristics called gate characteristics, such as durability, bending resistance, and rigidity, are required to be used in this read / write device.

As a material which satisfies such conditions and is easy to manufacture, generally, this prepaid card is mainly made of a plastic such as polyethylene terephthalate (PET) resin, that is, a resin satisfying only mechanical properties, as a card base material. We use as.

Further, polyvinyl chloride resin is used as a base material for general cards such as an ID card, a membership card, a cash card, and a credit card. Usually, after such a card is sold or lent to a user, it is discarded when the user finishes using the card. The plastic card of the above-mentioned material is currently disposed of by disposal after incineration or landfill as waste, but plastic waste has a high combustion temperature due to incineration according to the latter material. Incineration has problems such as durability and combustion gas and other pollution problems, and it is impossible to completely separate it from the former material, which is less affected by incineration. In the case of landfill as waste, since it remains in its original form without being decomposed at the landfill site, it remains semi-permanently as garbage, which has a problem of affecting the natural environment. In any case, there is a problem of disposal after use.

[0006] In addition, a card using paper as a card base material has been conventionally used. In particular, paper is easily disposed of by incineration or landfill, and the production cost is low. It is considered to be the best card material for solving environmental problems such as waste. However, when used as a paper card base, durability, bending resistance,
Considering the suitability as a card such as water resistance, chemical resistance, waterproofness, surface smoothness, glossiness, workability, etc., the function is inferior in all respects. However, it is limited to only temporary use such as a ticket, and is not suitable for the above-mentioned prepaid card used for a certain period.

In this case, it is conceivable that an outer layer other than plastic such as synthetic resin such as polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate or aluminum foil is laminated as a protective layer on a paper substrate.
These have the drawbacks that they are not excellent in disposability and are not much different from the plastic cards described above.

Accordingly, Japanese Patent Application Laid-Open No. 57-150393,
JP-A-59-220192, JP-A-51-939
No. 31, JP-A-63-260912, plastics that can be decomposed under natural environment such as light or underground have been developed, and are used for disposable type product packages. Has been commercialized.

In the field of cards, JP-A-5-42786 and JP-A-5-85088 describe the use of a biodegradable or photodegradable plastic for a card base material.

Therefore, many researches and developments of degradable polymers that do not cause these problems have been made before. Among these, lactic acid-based polymers are widely known for having high transparency and so-called biodegradability. The use in is expected.

Examples of biodegradable lactic acid-based polymers are disclosed in JP-A-6-32862 and JP-A-6-11.
JP-A-6356 discloses an example of a polyurethane foam obtained from a polyester polyol obtained using lactic acid as a starting material and polymethylene polyphenylene polyisocyanate. And a polyurethane resin obtained from hexamethylene diisocyanate.

Further, an application example in which a plasticizer and an ultraviolet absorber are introduced into a lactic acid-based polymer is disclosed in JP-A-7-177826. In addition, films are generally required to be rollable at the time of molding and lubricity at the time of product use, and to satisfy the above requirements for lactic acid-based polymers, a lubricant and an anti-blocking agent are introduced to make the film slippery. An application example in which the anti-blocking property and anti-blocking property are improved is disclosed in JP-A-8-34.
No. 913.

[0013]

Means for Solving the Problems Among the aliphatic polyesters, the present inventors have made crystalline polyesters synthesized from hydroxycarboxylic acids and diols having an exceptional melting point of 150 ° C. to 160 ° C. into higher physical properties. As a result of repeated studies to give physical properties that can be used as a film, the crystalline polyester was converted into 2,5- and / or 2,6 as a diisocyanate in a molten state at or above its melting point.
-A polyurethane resin comprising a polymer with diisocyanatomethylbicyclo [2,2,1] heptane has a practically sufficient high molecular weight, and a resin obtained by molding a polymer containing the same as a main component has thermal stability. And found that they have excellent tensile strength and stretchability, and have completed the present invention.

That is, the present invention provides 1) the following general formula (1)

Embedded image (Wherein R is a hydrocarbon group having 2 to 12 carbon atoms, and n is an integer of 2 or more), and a polyester diol having a repeating structure represented by the following formula:
Card base obtained by molding a polymer mainly composed of a polymer with diisocyanatomethylbicyclo [2,2,1] heptane 2) Polyester diol having a repeating structure represented by the general formula (1) 1) The card substrate according to 1), wherein the molecular weight is 50,000 or more; 3) a polyester diol having a repeating structure represented by the general formula (1);
A card comprising a mixture of a polymer with 2,5- and / or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane and an aliphatic polyester other than the polymer. It is a substrate.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the present invention, the polyester diol synthesized from the diol and the hydroxycarboxylic acid has a molecular weight of 50,000 or more, preferably 70,000 or more, and the terminal group is substantially a hydroxyl group. The film of the present invention is prepared by adding 2,5- and / or
Or 2,6-diisocyanatomethylbicyclo [2,2,
1] A card base material is obtained by molding a polymer containing a polymer obtained by reacting heptane as a main component.

Conventionally, a polyester having a hydroxyl group as a terminal group and having a number average molecular weight of about 2,000 to 2,500 has been used as a raw material component of a polyurethane resin and reacted with diisocyanate to form a rubber, foam, paint, adhesive and the like. It is widely done.

However, the polyester used for the existing polyurethane has a number average molecular weight of 2,000 to 2,500.
0, a so-called prepolymer. To obtain practical physical properties with respect to 100 parts by weight of the low-molecular-weight polyester, the amount of diisocyanate used is 10 parts by weight or more and 15 to 20 parts by weight, depending on the molecular weight of diisocyanate. It must be as high as parts by weight. However, for example, when 10 parts by weight of diisocyanate is added to a molten polyester (almost 150 ° C. or more depending on the type), a low-molecular-weight polyester always gels and can be handled regardless of a high-molecular-weight polyester. No resin can be obtained. In practice, the addition of more than 10 parts by weight of diisocyanate is done either in solution in a solvent, or as a final cured resin at one time, as in foam or RIM molding.

In the case of rubber, the hydroxyl group is converted to an isocyanate group (by adding diisocyanate), and the number average molecular weight is further increased with glycol. More than one part. In such a case, if a heavy metal-based catalyst is used in the synthesis of the polyester, it significantly promotes the reactivity of the isocyanate group, resulting in poor storage stability and undesired crosslinking (branching). Are synthesized without a catalyst. Therefore, even if the number average molecular weight is high, the limit is around 2,500.

In the present invention, the polyester diol to be reacted with the diisocyanate must be a polyester diol whose terminal group is substantially a hydroxyl group and has a molecular weight of 50,000 or more, preferably 70,000 or more. This is a low molecular weight polyester diol,
For example, when the molecular weight is about 20,000, the diisocyanate used in the present invention, that is, 2,5- and / or 2,6-diisocyanatomethylbicyclo [2,2,1]
Even when heptane is used, not only is it not possible to obtain a final resin having good physical properties, but also in the case of addition by melting, there are disadvantages such as the fact that even a small amount, gelation occurs during the reaction. Therefore, unless the terminal hydroxyl value is low, a safe reaction cannot be performed. The molecular weight of the present invention is 50,
Polymers having a molecular weight of 000 or more inevitably have a low terminal hydroxyl value, and can use a small amount of diisocyanate to safely synthesize a high molecular weight polymer even under severe conditions such as a molten state.

The molecular weight obtained by the present invention is 50,000.
As described above, desirably, 70,000 or more polyester diols and 2,5- and / or 2,6-diisocyanatomethylbicyclo [2,2,1] as diisocyanates.
A polymer having a polymer as a main component obtained by reacting heptane can form a resin having sufficient strength, and can be used as a card base material.

In the present invention, the following general formula (1)

Embedded image (Wherein, R is a hydrocarbon group having 2 to 12 carbon atoms, and n is an integer of 2 or more.) A polyester diol having a repeating structure represented by -And / or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane as a polymer which can be used in combination with a polymer having a main component as an aliphatic polyester containing a lactic acid unit and other polylactic acids (A) polylactic acid and a copolymer of lactic acid and another hydroxycarboxylic acid, (B) an aliphatic polyester containing a polyfunctional polysaccharide and a lactic acid unit, and (C) a fatty acid. Aliphatic polyesters containing aliphatic polyhydric carboxylic acid units, aliphatic polyhydric alcohol units and lactic acid units, and (D) mixtures thereof.

Lactic acid has an L-form and a D-form,
In the present invention, the term "lactic acid" refers to both L-form and D-form unless otherwise specified. Further, the molecular weight of the polymer refers to the weight average molecular weight unless otherwise specified.

The polylactic acid used in the present invention includes poly (L-lactic acid) whose structural unit is composed of only L-lactic acid, poly (D-lactic acid) whose structural unit is composed of only D-lactic acid, and poly (D-lactic acid) composed of L-lactic acid unit and D-lactic acid. Any of poly (DL-lactic acid) whose units are present in various ratios can be used. Examples of the hydroxycarboxylic acid of the lactic acid-other hydroxycarboxylic acid copolymer include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, and 6-hydroxycaproic acid. .

The method for producing polylactic acid used in the present invention includes a method of directly dehydrating and polycondensing L-lactic acid, D-lactic acid or DL-lactic acid, and a ring-opening polymerization of lactide which is a cyclic dimer of each of these lactic acids. And the like. Ring-opening polymerization is
The reaction may be performed in the presence of a compound having a hydroxyl group such as a higher alcohol or hydroxycarboxylic acid. The polylactic acid used in the present invention may be one produced by any of the above methods.

As a method for producing a lactic acid-other hydroxycarboxylic acid copolymer, a method of dehydrating and polycondensing each of the above lactic acid and the above hydroxycarboxylic acid, a lactide which is a cyclic dimer of each of the above lactic acids, and a cyclic form of the above hydroxycarboxylic acid And the like. The lactic acid-other hydroxy carboxylic acid copolymer may be produced by any of the above methods. The amount of lactic acid units contained in the copolymer is preferably at least 40 mol%.

Examples of the polyfunctional polysaccharide used for producing the polyfunctional polysaccharide and the aliphatic polyester containing a lactic acid unit include cellulose, cellulose nitrate, cellulose acetate, and the like.
Methylcellulose, ethylcellulose, celluloid, viscose rayon, regenerated cellulose, cellophane, cupra, cuprammonium rayon, cuprophan, Bemberg, hemicellulose, starch, amylopectin, dextrin, glycogen, pectin, chitin, chitosan, gum arabic, guar gum, locust bean gum , Acacia gum and the like and derivatives thereof. Of these, cellulose acetate and ethyl cellulose are particularly preferred.

As a method for producing a polyfunctional polysaccharide and an aliphatic polyester containing a lactic acid unit, a method of reacting the above polyfunctional polysaccharide with the above polylactic acid, lactic acid-other hydroxycarboxylic acid copolymer, or the like; Each of the above lactic acids,
A method of reacting cyclic esters and the like can be mentioned. The aliphatic polyester containing a polyfunctional polysaccharide and a lactic acid unit may be produced by any of the above methods. The amount of lactic acid units contained in the aliphatic polyester is at least 5
It is preferably 0% by weight.

Examples of the aliphatic polycarboxylic acid used for producing an aliphatic polyester containing an aliphatic polycarboxylic acid unit, an aliphatic polyhydric alcohol unit and a lactic acid unit include oxalic acid, succinic acid, malonic acid and glutaric acid. , Adipic acid, pimelic acid, suberic acid, azelaic acid, undecandioic acid, dodecandioic acid and the like and anhydrides thereof. These may be an acid anhydride or a mixture with an acid anhydride.

Examples of the aliphatic polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-
Butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol and the like.

As a method for producing an aliphatic polyester containing an aliphatic polycarboxylic acid unit, an aliphatic polyhydric alcohol unit and a lactic acid unit, the aliphatic polycarboxylic acid and the aliphatic polyhydric alcohol, the polylactic acid, Examples of the method include a method of reacting a lactic acid-other hydroxycarboxylic acid copolymer and the like, a method of reacting the aliphatic polycarboxylic acid and the aliphatic polyhydric alcohol with each of the above lactic acids, cyclic esters, and the like. The aliphatic polyester containing the aliphatic polycarboxylic acid unit, the aliphatic polyhydric alcohol unit and the lactic acid unit may be produced by any of the above methods.
The amount of lactic acid units contained in the aliphatic polyester is preferably at least 50 mol%.

The molecular weight of the lactic acid-based polymer affects the processability of the film and the strength and degradability of the resulting film. When the molecular weight is low, the strength of the obtained film is reduced, and the film may be broken by tension when used. In addition, the decomposition speed increases. Conversely, if it is too high, the processability decreases, and film formation becomes difficult. In consideration of this point, the molecular weight of the lactic acid-based polymer used in the present invention is from about 10,000 to about 100
A range of about 10,000 is preferable. A more preferred range is 100,000 to 300,000.

The optimum molecular weight and copolymer composition of the polymer used for the card base material of the present invention are changed depending on the intended use.

The resin of the present invention includes a lubricant, an anti-blocking agent, an ultraviolet absorber, a light stabilizer and the like, if necessary, a plasticizer, an antioxidant, a heat stabilizer, a filler, an anti-fog agent, an anti-fog. Additives such as agents, coloring inhibitors, pigments and the like can be used.

The molecular weight of 5 which is a constituent of the present invention
2,5- and / or 2,6-diisocyanates added to the polyester diol having a terminal group of at least 000, desirably at least 70,000 substantially hydroxyl groups to further increase the number average molecular weight. The use of diisocyanatomethylbicyclo [2,2,1] heptane has not been described before, and is particularly preferable in view of the hue of the formed resin, the reactivity when adding polyester, and the like. 2,5- and / or 2,6-diisocyanatomethylbicyclo [2,2,
1] The amount of heptane to be added depends on the molecular weight, but is 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, per 100 parts by weight of the polyester diol. The addition is desirably performed under a condition in which the crystalline polyester is in a homogeneous molten state, does not contain a solvent, and can be easily stirred. Separately,
It is practical to add it to the solid crystalline polyester production apparatus or to the crystalline polyester in the molten state (for example, in a kneader).

The method of molding the resin containing the various additives includes a melt extrusion method and a calender roll molding.
The substrate on the sheet is formed by a method appropriately selected. When performing melt extrusion, a known T-die method, inflation method, or the like is applied. The extrusion temperature is preferably in the range of 100 to 280 ° C, more preferably 130 to 280 ° C.
It is in the range of 50 ° C. If the molding temperature is low, it is difficult to obtain molding stability, and it is easy to fall into overload. Conversely, if the lactic acid-based polymer is too high, the lactic acid-based polymer may be decomposed, resulting in a decrease in the molecular weight, a decrease in the strength, coloring, etc.

Although the resin according to the present invention may be unstretched or stretched, it is preferable that the obtained film is uniaxially or biaxially stretched. In the case of uniaxial stretching, the film is stretched 1.3 to 5 times in the machine direction or the transverse direction. The stretching may be uniaxial stretching or biaxial stretching. In the case of biaxial stretching, uniaxial stretching and biaxial stretching may be performed sequentially or simultaneously. If the stretching ratio is low, it is difficult to obtain a film having a sufficiently satisfactory strength, and if it is high, the film often breaks during stretching, which is not preferable. In the case of uniaxial stretching, longitudinal stretching by a roll method or transverse stretching by a tenter is exemplified. In the case of biaxial stretching, these may be combined. The stretching temperature is preferably in the range of the glass transition point (Tg) to (Tg + 50) ° C. of the lactic acid-based polymer to be used. More preferably, Tg to (Tg + 30) ° C.
Range. If the stretching temperature is lower than Tg, stretching is difficult, and if it exceeds (Tg + 50) ° C., the strength may not be improved by stretching. After stretching, heat treatment may be performed at a temperature of 70 ° C. or higher and lower than the melting point after stretching in order to increase heat resistance. The heat treatment time is usually 1 second to 30 minutes.

[0037]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these without departing from the gist thereof. The molecular weight of the polymer was measured by gel permeation chromatography using chloroform as an eluent. All the experimental operations were performed in a nitrogen atmosphere.

(Reference Example) Synthesis of Modified Polylactic Acid Polyester Diol A 1 equipped with a stirrer, a thermometer, a cooling pipe, and a nitrogen introducing pipe.
After purging the L five-necked flask with nitrogen, polylactic acid (MW = about 100,00
0, hereinafter abbreviated as PLA) 100.0 g (1 × 10 ⁻³ mo)
l) and 300.0 g of dichloromethane were added, followed by 2-chloro-1,3-dimethylimidazolinium =
Chloride (1.1 times mol) was added, and the mixture was stirred and reacted at room temperature for 3 hours. Then, 1,4-butanediol (1
0 mol mol VS PLA), 3-methylpyridine (2 mol mol VS 2-chloro-1,3-dimethylimidazolinium chloride) is added, and 30 to 40 ° C.
And reacted for 3 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and the reaction solution was sequentially washed with a 10% aqueous hydrochloric acid solution and water. Thereafter, dichloromethane was removed under reduced pressure to obtain 101 g of a modified polylactic acid polyester diol. The yield is 100%. The molecular weight of the obtained modified polylactic acid polyester diol determined by GPC was 110,000, and the molecular weight distribution degree of dispersion (weight average molecular weight / number average molecular weight) was 3.0. The above method was repeated, except that the molecular weight of the crude PLA used was changed, and the molecular weight was 65,000, 78,
000 and 131,000 modified polylactic acid polyols were obtained.

Example 1 100 g of the modified polylactic acid polyester diol having a molecular weight of 110,000 obtained in Reference Example was dissolved by heating, and the stoichiometric number of 2,5- and / or 2,6-diisocyanatomethylbicyclo [2 , 2,1] heptane was added and kept for 1 hour to obtain a polymer having a melting point of 175 ° C. This polymer was kneaded using an extruder equipped with a T-die, melted and extruded to a thickness of 3
A resin of 00 μm was obtained. In the following Examples 2 to 4,
Polyurethane was synthesized by changing the molecular weight of the polyester diol used. However, the total amount of the polyol was the same as the number of moles of the modified polylactic acid polyester diol of Example 1.

Example 2 A resin having a thickness of 300 μm was obtained in the same manner as in Example 1, except that a modified polylactic acid polyester diol having a molecular weight of 65,000 was used as the polyester diol.

Example 3 A reaction and extrusion were carried out in the same manner as in Example 1 except that a modified polylactic acid polyester diol having a molecular weight of 78,000 was used as the polyester diol to obtain a resin having a thickness of 300 μm.

Example 4 A reaction and extrusion were carried out in the same manner as in Example 1 except that a modified polylactic acid polyester diol having a molecular weight of 131,000 was used as the polyester diol.
Resin was obtained.

Example 5 A reaction and a reaction were carried out in the same manner as in Example 1 except that a modified polylactic acid polyester diol having a molecular weight of 65,000 was used as the polyester diol, and this was mixed with polybutylene succinate at a ratio of 90:10. Extrude, thickness 3
A resin of 00 μm was obtained.

Example 6 A reaction and a reaction were carried out in the same manner as in Example 1 except that a modified polylactic acid polyester diol having a molecular weight of 78,000 was used as the polyester diol and polybutylene succinate was mixed at a ratio of 80:20. Extrude, thickness 3
A resin of 00 μm was obtained.

Example 7 A modified polylactic acid polyester diol having a molecular weight of 131,000 was used as a polyester diol, and polybutylene succinate was mixed at a ratio of 80:20. The resin was extruded to obtain a resin having a thickness of 300 μm.

Example 8 The same procedure as in Example 1 was carried out except that a modified polylactic acid polyester diol having a molecular weight of 131,000 was used as the polyester diol and polybutylene succinate was mixed at a ratio of 70:30. The resin was extruded to obtain a resin having a thickness of 300 μm. The polymers obtained in Examples 1 to 8 were subjected to IR measurement. Near 1600 cm ^-1 , N
Absorption due to -H bond was observed, and urethane bond (-
The formation of NHCOO-) was suggested.

[0047]

[Table 1] * (A): modified polylactic acid polyester diol (B): polybutylene succinate

[0048]

As described above, according to the present invention, a polyester diol having a repeating structure represented by the general formula (1) and having a molecular weight of 50,000 or more,
A card base material can be obtained by molding a polymer whose main component is a polymer with 5- and / or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J034 BA03 DA01 DB04 DB07 DF01 DF15 DF16 DF20 DF24 HA01 HA07 HC17 HC22 HC45 HC54 HC61 HC73 QA05 RA03 RA16

Claims (3)

[Claims] (1) The following general formula (1): (Wherein, R is a hydrocarbon group having 2 to 12 carbon atoms and n is an integer of 2 or more), and 2,5- and / or 2,6 having a repeating structure represented by the following formula:
A card base obtained by molding a polymer mainly composed of a polymer with diisocyanatomethylbicyclo [2,2,1] heptane; 2. The card substrate according to claim 1, wherein the polyester diol having a repeating structure represented by the general formula (1) has a molecular weight of 50,000 or more. 3. A polyester diol having a repeating structure represented by the general formula (1) and 2,5- and / or 2,2-
A card substrate comprising a polymer of 6-diisocyanatomethylbicyclo [2,2,1] heptane and an aliphatic polyester other than the polymer.