JP3427527B2 - Biodegradable laminate and biodegradable card - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable laminate and a biodegradable card in which a plurality of thermoplastic resins having biodegradability are mixed to improve physical properties such as mechanical strength and storage stability. Regarding

[0002]

2. Description of the Related Art Currently, a laminated body made of plastic such as synthetic resin is used as a card, a packaging material or a molding material. For example, the card is an ID card that proves your identity,
It is used in a wide range of fields such as membership cards, cash cards with monetary value, credit cards, prepaid cards, commuter passes, and pass tickets. In particular, as a card which has been used most frequently, there is a so-called prepaid card (prepayment card) in which a fixed amount of money is paid in advance and the value information of the amount is recorded. This card has value information via a read / write device,
With this reading / writing device, the identification information is recorded as picture / character information printed or printed on the card base material and machine-readable information in the magnetic recording part or optical recording part provided on the card base material. In order to be used, mechanical properties called gate properties such as durability, bending resistance, and rigidity are required. As a material that satisfies such conditions and is easy to manufacture, generally, this prepaid card mainly uses a plastic such as polyethylene terephthalate (PET) resin, that is, a resin satisfying only mechanical properties as a card base material. ing.

Further, polyvinyl chloride resin is used as a base material for general cards such as ID cards, membership cards, cash cards and credit cards. These are usually cards that are sold or rented to the user and then discarded when the user finishes using the card. And the plastic card of the above-mentioned material is currently disposed of by incineration or landfill as waste after the treatment after use, but the plastic waste is high heat of combustion temperature due to incineration according to the latter material. It has problems of durability of incinerator due to liquefaction, pollution of combustion gas, etc., 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, it remains in its original form without being decomposed at the landfill site, and remains semi-permanently as waste, which has a problem of affecting the natural environment. In any case, there is a problem of disposal after use.

Cards using paper as a card substrate have been used in the past. In particular, the paper is easy to incinerate or discard in landfill, and the manufacturing cost is low. It seems to be the best card material for solving environmental problems such as dust. However, when paper is used as the card substrate, durability, bending resistance, water resistance, chemical resistance, waterproofness, surface smoothness, glossiness,
Since the function is inferior in all respects considering the suitability as a card such as processability, the use of paper alone is limited to temporary use such as passage ticket, admission ticket, boarding ticket, and used for a certain period It has been said that it is not suitable for the above-mentioned prepaid card. In this case, polyethylene on the paper substrate,
It is conceivable that an outer layer other than plastic such as synthetic resin such as polypropylene, polyvinyl chloride, polyethylene terephthalate, etc., or aluminum foil may be laminated as a protective layer, but these are not excellent in disposability, and there is a big difference with the above plastic card. Have.

Therefore, Japanese Patent Laid-Open No. 57-150393 / 1982,
JP-A-59-220192, JP-A-51-939
As described in JP-A-91, JP-A-63-260912, and JP-A-57-150393, plastics that can be decomposed in the natural environment such as light or underground have been developed, and especially disposable products. Used for packaging,
Currently, some are commercialized. In the field of cards, JP-A-5-42786 and JP-A-5-85 by the present applicant
No. 088 describes the use of biodegradable or photodegradable plastic for the card substrate.

[0006] Furthermore, Japanese Patent Application No. 5-1447 filed by the present applicant.
There is a card having a biodegradable resin layer according to No. 38 on one or both sides of a paper base material, which has characteristics as a conventional plastic card and has excellent disposability, but there is no problem in normal use, but it is abnormal. When exposed to water, such as when washing in a clean environment, water will seep into the edge of the card,
The card may be curled, expanded or contracted, and the edge portion may be turned over, which causes a problem such as damage to the card and a failure such as being caught in a card transport path when used in a reading / writing device.

[0007]

By the way, among biodegradable resins available at present, as a biodegradable resin satisfying mechanical properties such as bending resistance and rigidity required as a card by itself, for example, Examples thereof include a polymer sheet containing polylactic acid or a copolymer of lactic acid and oxycarboxylic acid as a main component. However, this biodegradable resin has a drawback that it hydrolyzes during storage and becomes brittle, which is a problem in terms of water resistance. This can be solved by removing the residual catalyst used during synthesis and unreacted monomers that cause this hydrolysis, but this polylactic acid-based polymer has its polymer chain shortened by the initial hydrolysis, resulting in a lower molecular weight. Later, since it is biodegraded, if hydrolysis is suppressed, biodegradation becomes extremely slow, and it is necessary to accelerate the decomposition under heating conditions such as in compost equipment. Occurs. on the other hand,
In terms of degradability, for example, polyhydroxyvalerate / butyrate copolymers and aliphatic polyesters are biodegradable in the soil and activated sludge due to the enzyme from the high molecular state, and are said to have excellent biodegradability. Although it has a mechanical property similar to that and has softness, it is inferior in mechanical strength such as rigidity suitable for gate characteristics such as rigidity during mechanical reading / writing.

When a resin having a decomposability is simply used as a card base material, it is considered that the resin is gradually decomposed after being discarded due to the function of the resin. There is a problem that it cannot be said that the mechanical properties such as toughness and rigidity or storage stability are satisfied. Therefore, an object of the present invention is to provide a biodegradable card which has gate characteristics such as rigidity required for machine reading / writing and which can be decomposed under normal conditions.

[0009]

In order to achieve the above object, the present invention provides a polylactic acid having a number average molecular weight of 10,000 to 100,000 or a copolymer of lactic acid and an oxycarboxylic acid. Thermoplastic resin as main component and number average molecular weight of 10,000 to 100,000
A biodegradable laminate, which is obtained by kneading the thermoplastic resin represented by the general formula (1) and a filler.

[Chemical 3]

According to the second aspect of the present invention, a thermoplastic resin containing polylactic acid having a number average molecular weight of 10,000 to 100,000 or a copolymer of lactic acid and oxycarboxylic acid as a main component, and a number average molecular weight of 25,000 to 70,000 are generally used. A biodegradable laminate, which is obtained by kneading a thermoplastic resin represented by formula (2) and a filler.

[Chemical 4]

According to a third aspect of the present invention, a thermoplastic resin containing polylactic acid having a number average molecular weight of 10,000 to 100,000 or a copolymer of lactic acid and oxycarboxylic acid as a main component, 3-hydroxyvalerate and 3-hydroxy. Biodegradable laminate comprising a degradable resin obtained by kneading an aliphatic polyester resin having a hydroxyalkanoate unit consisting of butyrate, 3-hydroxycaprolate and 3-hydroxyheptanoate and a filler. It is the body.

The invention according to a fourth aspect is the first to the third aspects.
The biodegradable laminate according to any one of items 1 to 3 , wherein the lactic acid is D-lactic acid, L-lactic acid, or a mixture thereof .

The invention described in claim 5 is the invention as claimed in claims 1 to 3.
In the biodegradable laminate according to any one of the oxycarboxylic acid is glycolic acid or a 6-hydroxycaproic acid in the biodegradable laminate characterized by,
is there.

The invention according to a sixth aspect is the first to fifth aspects.
The biodegradable laminate according to any one of items 1 to 3 , wherein the thermoplastic resin and the filler are kneaded and then biaxially stretched .

According to a seventh aspect of the present invention, in the biodegradable laminate according to the third aspect, the hydroxyalkanoate unit is 3-hydroxyvalerate, 3-hydroxybutyrate, 3-hydroxycaprolate. , 3-
A biodegradable laminate comprising one or a mixture of two or more hydroxyheptanoates .

The invention according to claim 8 is the invention according to claims 1 to 7.
A biodegradable card comprising the biodegradable laminate according to any one of items 1 to 3 as a base material.

[0017] The invention according to claim 9, in biodegradable card according to claim 8, biodegradation, characterized in that the magnetic recording layer and / or heat-sensitive recording layer formed on the substrate It is a sex card.

[0018]

According to the biodegradable laminate and biodegradable card of the present invention, a base material is a thermoplastic resin containing polylactic acid or a copolymer of lactic acid and oxycarboxylic acid as a main component, an aliphatic polyester and a filler. A biodegradable resin made by kneading has the mechanical strength and storage stability of the base material, and especially has the same durability, bending resistance, rigidity, molding processability, and water resistance as a vinyl chloride card. It shows card suitability such as resistance, chemical resistance, waterproofness, surface smoothness, glossiness, etc. and does not interfere with machine reading / writing. Furthermore, it can be fully decomposed naturally even if it is left after disposal.

[0019]

The present invention will be described in detail below. One of the materials constituting the laminate and the card of the present invention uses a biodegradable resin made of an aliphatic polyester, which is a polymer material containing lactic acid or the like as a main component, and these are degradable as described above. It has already been used mainly as a bioabsorbable material in the field of medical materials as a suture thread or a bone joint. Examples of lactic acid include D-lactic acid and L-lactic acid, and examples of oxycarboxylic acid include glycolic acid and 6-hydroxycaproic acid. In the present invention, D-lactic acid, L-lactic acid or a mixture thereof and D-lactic acid are used. , L-lactic acid or a mixture thereof and glycolic acid, or a thermoplastic degradable polymer containing a copolymer of oxycarboxylic acid represented by 6-hydroxycaproic acid as a main component. This polymer preferably has a number average molecular weight of 10,000 to 1,000,000. By the way, the rigidity is not sufficient only with the thermoplastic polymer.

Since this lactic acid has a hydroxyl group and a carboxyl group in the molecule, polycondensation is possible. However, dehydration condensation yields only an oligomer having a low polymerization degree of less than 4000 and therefore once as an oligomer of lactic acid. From this, a polymer can be obtained by the method of ring-opening polymerization (indirect method). Further, a method using a catalyst and JP-A-59-96123
JP-A-63-289020, a method for obtaining polylactic acid having a molecular weight of 4000 or more by heating and pressurizing in an inert gas atmosphere (direct method) without using a catalyst,
There is a method of obtaining a thermoplastic polymer by copolymerization of lactic acid and glycolic acid, tartaric acid, malic acid, polyethylene glycol or the like. Incidentally, the production method relating to the polymerization of lactic acid is shown in US Patent Nos. 1995970, 2362511 and 2683136, and the production method of a copolymer of lactic acid and glycolic acid is described in US Pat.
No. 3797449. The copolymer is more likely to increase the degree of polymerization.

The other material constituting the laminate and the card of the present invention has a number average molecular weight of 10,000 to 100,000.
A thermoplastic resin represented by the general formula (1):

[Chemical 5] Or a thermoplastic resin represented by the general formula (2) having a number average molecular weight of 25,000 to 70,000,

[Chemical 6] Alternatively, there is an aliphatic polyester resin having a hydroxyalkanoate unit composed of 3-hydroxyvalerate, 3-hydroxybutyrate, 3-hydroxycaprolate, and 3-hydroxyheptanoate.

The aliphatic polyester represented by the general formula (1) is obtained by polycondensing an aliphatic (including cycloaliphatic) glycol with an aliphatic (including cycloaliphatic) dicarboxylic acid (or an acid anhydride thereof). The resulting polyester is an aliphatic polyester having a urethane bond which has been polymerized in the presence of diisocyanate or polyisocyanate,
The number average molecular weight is 10,000 to 100,000. A general method for synthesizing this resin is disclosed in JP-A-4-189822.

The aliphatic polyester represented by the general formula (2) is an aliphatic (including cycloaliphatic) glycol or a mixture thereof, and an aliphatic (including cycloaliphatic) dicarboxylic acid (or an acid anhydride thereof). ) Or a mixture thereof, which is an aliphatic polyester containing no urethane bond and having a high molecular weight without using diisocyanate as a coupling agent, having a number average molecular weight of 2
It is 5000 to 70,000. A general method for synthesizing this resin is disclosed in JP-A-4-122205.

Aliphatic polyester resins having a hydroxyalkanoate unit represented by 3-hydroxyvalerate, 3-hydroxybutyrate, 3-hydroxycaprolate and 3-hydroxyheptanoate are
For example, a copolymer comprising 3-hydroxyvalerate and 3-hydroxybutyrate units is fermentatively synthesized by biosynthesis from hydrogen peroxide and propionic acid and glucose (PA Holmes: Phys. Techno).
l. , 16.32 (1985). In particular, an aliphatic polyester resin having a 3-hydroxyvalerate fraction of 0 to 25 mol% is marketed as "Biopol (trademark)".

In addition to the above resins, inorganic fillers such as calcium carbonate, mica, calcium silicate,
White carbon, asbestos, porcelain clay (calcined), glass fiber, etc. are added and kneaded to prepare a base material constituting the card of the present invention. Mixing ratio (weight ratio) of the thermoplastic resin containing the above-mentioned polylactic acid or the copolymer of lactic acid and oxycarboxylic acid as the main component and the aliphatic polyester resin
Is 97: 3 to 80:20, preferably 95: 5 to
It is 90:10. In addition, if necessary, various additives such as 0.05 to 3 parts by weight of anti-coloring agent and 0.05 to 3 parts by weight of antioxidant, as long as the properties of the kneaded resin other than the filler are not lost. 0.05 to 0.5 parts by weight of lubricant,
It is possible to add organic pigments and inorganic pigments. However, it is not preferable to add 50% or more of a non-decomposable substance, because the decomposability is remarkably lowered and a processing problem occurs.

The method of kneading the above resins and the like includes dry blending and melt blending, and the method of molding the kneaded resin includes T-die extrusion and calender roll molding. Is formed into a base material. Furthermore, by biaxially stretching the sheet-shaped base material under heating, the rigidity, moldability, mechanical strength, hardness,
Mechanical properties such as impact strength, dimensional stability, and bending resistance, and surface smoothness, glossiness, water resistance, and water resistance can be improved. In these respects, it has properties equivalent to conventional polyester materials and vinyl chloride materials.

In addition to the above single-layer structure, the base material may have a multi-layer structure in which sheet-like base materials made of other resin materials having the same or different mixing ratios or different ones are prepared and laminated.

The substrate produced by the above method can be printed / processed in the same manner as in the case of the conventional paper / plastic card, and the printing method such as offset printing, screen printing or gravure printing is performed on the substrate. With this, it is possible to manufacture a card by printing visible information / design such as characters and pictures and processing it into a card size using a punching machine.

Further, in the card of the present invention, an information recording layer capable of mechanically recording / reproducing data such as digital information such as a magnetic recording layer or a heat sensitive recording layer can be formed.
A plurality of different information recording layers such as the magnetic recording layer and the heat sensitive recording layer can be formed on the same card.

The method for forming the magnetic recording layer is known, and a coating liquid in which a magnetic recording material is dispersed in a binder or the like is applied, or a sheet having the magnetic recording layer is laminated.
Similarly, a method of forming a heat-sensitive recording layer is also known, and it can be formed by coating a heat-sensitive recording material such as a heat-sensitive leuco dye or a heat-sensitive diazo dye, or a low-melting metal thin film such as tin or aluminum.

Hereinafter, specific examples of the present invention will be described in detail. <Example 1> L-lactic acid having a number average molecular weight of 80,000 and 6-
55 wt of 3: 2 hydroxycaproic acid copolymer
%, 5 wt% of the aliphatic polyester resin represented by the general formula (1) having a number average molecular weight of 50,000, 35 wt% of mica as an additive (HAR160 manufactured by Shiraishi Industry Co., Ltd.), and 5 wt% of titanium oxide (dried at 200 ° C. for 24 hours) are vented. After kneading with an extruder, this was extruded with a T-die melt extruder at a processing temperature of 200 ° C. to a prescribed thickness, then biaxially stretched and calendered to obtain a 188 μm-thick layer with improved surface smoothness. A sheet was prepared. This sheet had a flexural modulus of 43000 kgf / cm ² and had properties close to those of a polyethylene terephthalate (PET) resin sheet.

When this sheet was left in an environment of 40 ° C. and humidity of 90% for 48 hours, there was no change in bending strength and no odor was generated.

A magnetic coating material having the following composition was formed on this sheet by knife coating to form a black magnetic recording layer of about 10 μm, magnetic field orientation was applied in a horizontal magnetic field of about 3000 gauss, and then hot air of 100 ° C. was applied for 3 minutes. Dried. Magnetic paint Magnetic powder (1750 Oe: barium ferrite) 100 parts by weight Vinyl chloride-vinyl acetate copolymer (VAGF: Union Carbide Co.) 20 parts by weight Polyurethane resin (Nipporan 2304: Nippon Polyurethane Industry Co., Ltd.) 30 parts by weight Hexa Methylene diisocyanate (Coronate HX: manufactured by Nippon Polyurethane Industry Co., Ltd.) 2 parts by weight Carbon black (# 3000: manufactured by Mitsubishi Chemical Co., Ltd.) 5 parts by weight Dispersant (Garfuck RE-610: manufactured by Toho Chemical Co., Ltd.) 3 parts by weight Diluting solvent (toluene) / MEK / MIBK) 100 parts by weight

This sheet is 57.5 mm in length x 85.0 in width
A card was obtained by processing into a card size of mm cybernetic standard. When this card was passed through a gate having a card reading / writing device at a speed of 2 m / sec for about 500 times, no card abnormality such as card clogging occurred. Next, this card was immersed in water for 30 seconds, wiped off the water and passed through the gate in the same manner, but no card abnormality such as card clogging occurred. The stiffness at this time is 3
It was 0 gf / cm, and there was no change before and after immersion in water. Furthermore, when this card was embedded in field soil and the decomposed state was observed, after 10 months, it was decomposed to a state in which the magnetic recording layer was left and the shape was not retained.

Table 1 shows an example in which the mechanical strength of the card of the embodiment is compared with that of other members. This is JIS P 81
25, the rigidity (gf / cm) of the short side of the card was measured, and the water immersion test was performed by immersing the card in water for 30 seconds and then wiping off the water. In Comparative Example 1, a filler was added to the polylactic acid simple substance used in Example 1, kneading,
It is biaxially stretched.

[0036]

[Table 1]

In particular, when the card of Example 1 and the card of Comparative Example 1 were left in activated sludge and observed with time, the card of Comparative Example 1 after 4 months showed no change in weight. The card of No. 1 was found to have reduced weight and mechanical strength. <Example 2> L-lactic acid having a number average molecular weight of 150,000 and 6
55% of a 3: 2 copolymer of hydroxycaproic acid
%, 5 wt% of the aliphatic polyester resin represented by the general formula (2) having a number average molecular weight of 10000, 35 wt% of mica as an additive (manufactured by HAR160 Shiraishi Industry Co., Ltd.), and 5 wt% of titanium oxide after kneading with a vent type extruder. , This is extruded by a T-die melt extruder at a processing temperature of 200 ° C. to a specified thickness, then biaxially stretched and calendered,
A sheet having a thickness of 188 μm with improved surface smoothness was produced. This sheet has a flexural modulus of 41,000 kgf / c
m ² was obtained, and characteristics similar to those of a polyethylene terephthalate (PET) resin sheet were obtained.

When this sheet was left in an environment of 40 ° C. and 90% humidity for 48 hours, there was no change in bending strength and no offensive odor was generated.

A black magnetic recording layer of about 10 μm was formed on this sheet by knife coating with the magnetic coating material of Example 1, subjected to magnetic field orientation in a horizontal magnetic field of about 3000 gauss, and then dried with hot air at 100 ° C. for 3 minutes. Let

This sheet is 57.5 mm in length and 85.0 in width.
A card was obtained by processing into a card size of mm cybernetic standard. When this card was passed through a gate having a card reading / writing device at a speed of 2 m / sec for about 500 times, no card abnormality such as card clogging occurred. Next, this card was immersed in water for 30 seconds, wiped off the water and passed through the gate in the same manner, but no card abnormality such as card clogging occurred. The stiffness at this time is 3
It was 0 gf / cm, and there was no change before and after immersion in water. Furthermore, when this card was embedded in field soil and the decomposed state was observed, after 10 months, it was decomposed to a state in which the magnetic recording layer was left and the shape was not retained.

As a comparative example, the card made of stabilized polylactic acid alone was left in activated sludge as a comparative example, and the change over time was observed. However, the card of Example 2 showed a decrease in weight and a decrease in mechanical strength.

<Example 3> Number average molecular weight of 150,000
L-lactic acid and 6-hydroxycaproic acid 3: 2 copolyester
55 wt% mer, 3-hydroxyvalerate and 3-hi
Copolymers consisting of units of droxybutyrate [UK
Zeneca Biopol ™ hydroxy valile
5% by weight and mica 35 as an additive
wt% (HAR160 manufactured by Shiroishi Industry Co., Ltd.), titanium oxide 5
After kneading wt% by vent type extruder, melt this by T-die
Extruded to a specified thickness with an extruder at a processing temperature of 200 ℃
After that, biaxial stretching and calendering are applied to the surface
A 188 μm thick sheet with improved smoothness was prepared.
It was This sheet has a flexural modulus of 39000 kgf / cm.
²Shows polyethylene terephthalate (PET) resin
The characteristics close to those of the sheet were obtained.

This sheet was left in an environment of temperature 40 ° C.-humidity 90% for 48 hours, but there was no change in bending strength.
There was no offensive odor.

A black magnetic recording layer of about 10 μm was formed on this sheet by knife coating with the magnetic coating material of Example 1, magnetic field orientation was applied in a horizontal magnetic field of about 3000 gauss, and then dried with hot air at 100 ° C. for 3 minutes. Let

This sheet is 57.5 mm in length x 85.0 in width
A card was obtained by processing into a card size of mm cybernetic standard. When this card was passed through a gate having a card reading / writing device at a speed of 2 m / sec for about 500 times, no card abnormality such as card clogging occurred. Next, this card was immersed in water for 30 seconds, wiped off the water and passed through the gate in the same manner, but no card abnormality such as card clogging occurred. The stiffness at this time is 3
It was 0 gf / cm, and there was no change before and after immersion in water. Furthermore, when this card was embedded in field soil and the decomposition state was observed, after 8 months, it was decomposed to a state where the shape was not retained, leaving the magnetic recording layer.

As a comparative example of the card of Example 3, a card made of polylactic acid alone prepared by adding a filler and biaxially stretching was allowed to stand in activated sludge, and the change with time was observed. No change in weight was observed for the card of Comparative Example 1 and a decrease in weight and a decrease in mechanical strength were observed for the card of Example 3.

All of the cards of Examples 1 to 3 were left indoors (room temperature) and had no change in mechanical properties such as bending strength after 10 months.

[0048]

As described above, according to the biodegradable laminate and the biodegradable card of the present invention, a base material is a thermoplastic resin containing polylactic acid or a copolymer of lactic acid and oxycarboxylic acid as a main component, By using a biodegradable resin made by kneading an aliphatic polyester and a filler, it shows storage stability without material deterioration during storage, can be surely biodegradable at the time of disposal, and has rigidity and moldability. It has excellent mechanical properties such as mechanical strength, hardness, impact strength, dimensional stability, and bending resistance, and in particular, in the case of a card, it has gate characteristics that can be used in a mechanical reading / writing machine. That is, it is a biodegradable card that satisfies all the conditions of mechanical properties as a card, storage stability and biodegradability, and that can sufficiently replace the card using a conventional plastic.

The biodegradable resin used in the card of the present invention is subjected to an additive or biaxial stretching process on the surface which is inferior in physical properties and processability to conventional plastics to the extent that the degradability is not deteriorated. It is also possible to improve physical properties and workability.

Further, as the biodegradable laminate of the present invention,
It can be used for packaging materials such as packaging containers, trays, and storage containers, and molding materials, and does not biodegrade in the environment where it is normally used, such as indoors, and can be sufficiently replaced with the plastic materials currently used. Therefore, when it is discarded by other than incineration, it is promptly and surely decomposed, and the influence on the environment can be reduced.

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Claims (9)

(57) [Claims] 1. A number average molecular weight of 10,000 to 100,000.
A thermoplastic resin containing polylactic acid or a copolymer of lactic acid and oxycarboxylic acid as a main component, and having a number average molecular weight of 1
A biodegradable laminate, which is obtained by kneading a thermoplastic resin represented by the general formula (1) of 0000 to 100000 and a filler. [Chemical 1] 2. A number average molecular weight of 10,000 to 100,000.
A thermoplastic resin whose main component is polylactic acid or a copolymer of lactic acid and oxycarboxylic acid, and a number average molecular weight of 2
A biodegradable laminate, which is obtained by kneading a thermoplastic resin represented by the general formula (2) of 5000 to 70000 and a filler. [Chemical 2] 3. A number average molecular weight of 10,000 to 100,000.
Which is a degradable resin obtained by kneading a thermoplastic resin containing polylactic acid or a copolymer of lactic acid and oxycarboxylic acid as a main component with an aliphatic polyester resin having a hydroxyalkanoate unit and a filler. Biodegradable laminate. Wherein said lactic acid is D- lactic, L- lactic acid or claims 1 to 3 Neu, characterized in that a mixture thereof
The biodegradable laminate according to item 1 . 5. The oxycarboxylic acid is glycolic acid or 6-hydroxycaproic acid.
The biodegradable laminate according to any one of claims 1 to 3 . 6. After kneading the thermoplastic resin and the filler, claims 1 to 5, characterized in that biaxially stretched
The biodegradable laminate according to any one of 1 . 7. The hydroxyalkanoate unit comprises one or a mixture of two or more of 3-hydroxyvalerate, 3-hydroxybutyrate, 3-hydroxycaprolate, 3-hydroxyheptanoate. The biodegradable laminate according to claim 3, which is characterized in that. 8. A biodegradable card comprising the biodegradable laminate according to any one of claims 1 to 7 as a base material. 9. A magnetic recording layer and / or a heat-sensitive recording layer are formed on the base material according to claim 8.
Biodegradable card as described .