JPH0425436A - Frost treatment of card - Google Patents

Abstract

PURPOSE:To heat a card only during ultrasonic oscillation, to cool the card quickly by an ultrasonic oscillation head when oscillation is stopped and to obtain a uniform frost in specified depth by executing frost treatment by the ultrasonic oscillation head. CONSTITUTION:A card 1 is placed on a cradle 3, and a head 2 is lowered and the card 1 is held. When the head 2 is ultrasonic-oscillated under the state, the recording surface of the card 1 is heated only during the oscillation, and frost-treated. When oscillation is stopped, heating is stopped. Since head 2 itself is not heated and is brought to a temperature near to normal temperature at all times, the frost-treated recording surface is cooled by the head 2, and a frost, in which no frost returns and which has specified depth, is obtained. The frost treatment is executed at a temperature higher than the glass transition temperature (Tg) of the resin of a smooth layer 11 and lower than the melting point (Tm) in order to retain distortion.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is for repeatedly forming and erasing clearly visible recorded images on cards that are used repeatedly, such as commuter passes, admission passes, and various prepaid cards. The present invention relates to a method for frosting the surface of a card.

(Prior Art) Commuter passes for public transportation, permits for entering event venues and buildings, etc. are used repeatedly every day, but due to management reasons, there is no way to check for unauthorized boarding or unauthorized entry.

In recent years, a magnetic card-based check method has been adopted in some areas, but since the presence or absence of a check cannot be visually checked, there is a risk of a check being omitted due to equipment trouble, which was inconvenient for both administrators and users. .

Also, various prepaid cards include magnetic cards and I/O cards.
Although C cards are used, the recorded contents cannot be viewed directly, so it is not possible to easily check the payment amount or balance.
There was a problem in terms of guaranteeing the content to users.

Previously, there were methods to print usage details on the card each time the card was used, or to display the approximate value of the remaining amount by punching a hole, but these methods could not erase the records, so there was a limit to the number of times the card could be used. It is not suitable for cards that have a large number of charges or that require accurate balance display.

Therefore, the present applicant first proposed a method that can repeatedly create and erase visible records on commuter passes and various prepaid cards.

The method involves using a card with a smooth layer made of synthetic resin on the surface, forming a heat-erasable frosted surface on the smooth layer, and heat-erasing the frosted surface to return it to a smooth surface. This method creates a visually visible image based on the contrast between the frosted surface and the smooth surface, that is, the difference in light reflectance.

(Problem to be Solved by the Invention) As a method for frosting a card, as shown in a cross-sectional view in FIG.
A conceivable method is to sandwich the card 1 between the frost plate 20, which is not heated in step 2, and the elastic receiver 30. However, when frosting is performed using this method, since the frost plate 20 is constantly heated, the applied frost slightly returns at the moment the frost plate 20 is released, making it impossible to form a frost of the desired depth. vending machines, ticket vending machines,
When frosting is performed inside a ticket inspection machine, etc., the frosting is required to be completed in a short period of time, and the return of the frosting is large, which poses a problem.

(Means for Solving the Problems) The present invention provides heat-erasable frosting in a uniform and desired manner in order to record visually visible, repeatable and erasable records on cards such as commuter passes, admission tickets, and various prepaid cards. The present invention provides a method for forming a material at a depth of .

That is, the present invention forms a smooth layer of synthetic resin on at least a portion of the surface of the card, and frosts the smooth layer at a temperature above the glass transition temperature and below the melting point of the resin to retain distortion. This is a method for frosting a card, characterized in that the frosting is performed by pressing an ultrasonic oscillation head made of frosted material against the smooth layer to oscillate ultrasonic waves.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view showing an example of a card manufactured by the method of the present invention, FIG. 2 is a cross-sectional view showing how to use the card, FIG. 3 is a cross-sectional view showing the frosting method of the present invention, and FIG. FIG. 2 is a cross-sectional view showing a conventional frost treatment method.

To explain the card obtained by the present invention with reference to FIG. 1, the card 1 is made by laminating a smooth layer 11 made of synthetic resin and a support layer 12 such as a strong polyethylene terephthalate sheet or paper. Recording side 13
The other surfaces are printed 14 to display necessary explanations and decorative designs. Further, it usually has a function of storing information, performing calculations, etc. by providing a magnetic layer or the like.

To explain how to use this card using Figure 2, (A
The recording surface 13 of the card 1 having the smooth layer 11 as shown in ) is subjected to frosting (surface roughening) treatment as shown in FIG.

By performing this frosting at a temperature not lower than the glass transition temperature (Tg) and lower than the melting point (Tm) of the resin of the smooth layer 11, the frosted surface retains a distortion that tends to return to the original smooth surface by heating.

To record on this card, as shown in (C), when the frosted surface 15 of the card is partially heated at a higher temperature than the frosting temperature, only the heated portion returns to a smooth surface, and the frosted surface 15 becomes smooth. Due to differences in surface reflectance, letters, etc.
An image 16 of figures, symbols, etc. appears. Examples of heating methods include a method in which a heated stamp is placed close to or under pressure, a method using a laser beam, and a method using a thermal head used in a normal thermal printer.

When erasing a record, the entire surface of the recording surface 13 is frosted to erase the image 16. This frost treatment, like the first frost treatment,
Do the following to retain distortion internally. As a result, the card 1 returns to the state shown in (B) before image formation, and can be used repeatedly thereafter.

The present invention relates to the frost treatment from (A) to (B) or (C) to (B) in FIG. 2, and as shown in FIG. 3, an ultrasonic oscillation head 2, The card 1 is held between the elastic holder and the stand 3.

The ultrasonic oscillation head 2 has a frosted surface 21 on the lower surface, and is connected to an ultrasonic oscillator (not shown).

The elastic support base 3 is made of an elastic material such as rubber in its entirety or surface, and is placed on an anvil 31.

To perform the frosting process, first place the card 1 on the stand 3.
is placed, the head 2 is lowered to sandwich the card 1, and when the head 2 is caused to oscillate ultrasonic waves in this state, the recording surface of the card 1 is heated and frosted only during the oscillation. Next, when the oscillation is stopped, the heating stops. Since the head 2 itself is not heated and is always at a temperature close to room temperature, the frosted recording surface is cooled by the head 2, and a predetermined depth of frost is obtained without returning the frost.

This frosting process is performed on the smooth layer 1 in order to retain distortion.
Above the glass transition temperature (Tg) of the resin in No. 1, the melting point (Tm)
Perform at the following temperatures. At temperatures lower than Tg, frosting does not cause distortion, or the distortion that occurs is rapidly released without heating.

Further, at a temperature higher than Tm, the formed frost has no distortion and cannot be erased even by reheating, so that the object of the present invention cannot be achieved.

This temperature can be adjusted by adjusting the oscillation time, amplitude, frequency, etc. of the head 2.

In addition, in the case of non-quality resins, they often do not show a clear Tm, or in that case, the flow start temperature is taken as Tm. Also, in the case of crosslinked resins that generally do not show a Tm, the flow start temperature (
or decomposition temperature) or below. Furthermore, when a mixed resin or a copolymer resin exhibits two or more Tg's, the higher Tg may be used as the reference.

As for the condition of the frost, it is preferable that the surface roughness of the frosted surface 15 is in the range of 1 to 10 μm in 10-point average roughness Rz according to J I 5-B-0601.

If Rz is less than 1 μm, even if a smooth image is formed on the frosted surface during recording, it is difficult to determine the presence or absence of an image, and 10
If it exceeds μm, it will take time to smooth it during recording.
Moreover, it is necessary to raise the heating temperature, which is disadvantageous in terms of equipment.

As the resin constituting the smooth layer 11, various resins such as polystyrene, polypropylene, polyvinyl chloride, polystyrene, polymethyl (meth)acrylate, polyethylene terephthalate, polyamide, polycarbonate, ABS resin, or copolymer resins thereof may be used alone or in combination. They can be used in combination. Among them, polyvinyl chloride, polystyrene, polymethyl (meth)acrylate,
Non-grade resins such as polycarbonate are preferred because they are easy to handle.

Furthermore, crosslinkable acrylic resins, crosslinkable urethane resins, or the various resins mentioned above can be treated with crosslinking agents, electron beams, gamma rays, etc.
It is also possible to use a resin that has been crosslinked to the extent that it does not lose its heat fluidity.

The thickness of the smooth layer 11 is usually in the range of 5 to 200 μm,
There is no particular limit to the overall thickness of the card 1, but it is 0.1
It is about ~3 mm.

As this smooth layer 11, a film or sheet formed by extrusion molding or the like may be used, or it may be formed by coating.

The card obtained by the method of the present invention can visually display the main information recorded on the magnetic layer etc. as an image, and can be used for checking traffic openings, entering/exiting facilities, and restaurants. It can be used to record and display the amount spent and balance on prepaid cards used in shops, vending machines, etc.

(Effects of the Invention) According to the method of the present invention, by performing the frosting process using the ultrasonic oscillation head, the card is heated only during the ultrasonic oscillation, and when the oscillation is stopped, the card is rapidly cooled by the ultrasonic oscillation head. , a uniform frost of a predetermined depth can be obtained.

(Example) (Comparative example) A polyethylene terephthalate sheet (thickness 188 μm) was used as the support layer 12, and a smooth layer 11 (colorless transparent polyvinyl chloride resin with a thickness of 15 μm, Tg 70 ° C.
, Tm 202°C), and a recording surface 1 of 1010 x 20
Make the card shown in Figure 1 by printing 14, leaving out 3.

Then, on the recording surface 13, a heating frost plate 20 in which a frosted surface with an Rz of 3 μm was formed on a 1010×20 smooth metal plate by electric discharge machining, and a rubber support stand 30 were used.
When frosting was performed using the method shown in FIG. 4 at a temperature of 150° C., a time of 0.3 seconds, and a pressure of 10 kg, only a transferred frost with an Rz of 2 μm was obtained.

(Example) For the same card as the comparative example, Rz
Using the ultrasonic oscillation head 2 on which a frosted surface 21 of 3 μm was formed, a frequency of 20 KHz was generated by the method shown in FIG.
When frosting was performed under the conditions of , output soow, @width 10 μm, oscillation time 0.3 seconds, and pressurizing force 10 kg, R
A uniform frost of z3 μm was obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a card manufactured by the method of the present invention, FIG. 2 is a cross-sectional view showing how to use the card, FIG. 3 is a cross-sectional view showing the frosting method of the present invention, and FIG. FIG. 3 is a cross-sectional view showing a conventional frost processing method. 1...Card 11...Smooth layer 15...
Frosted surface 16...Image 2...Ultrasonic oscillation head patent applicant Mitsubishi Plastics Co., Ltd. agent Patent attorney Kumi Kondo Diagram

Claims (1)

[Claims] A smooth layer of synthetic resin is formed on at least a portion of the surface of the card, and the smooth layer is frosted at a temperature above the glass transition temperature and below the melting point of the resin to retain distortion. A method for frosting a card, characterized in that frosting is performed by pressing a sonic oscillation head against the smooth layer to generate ultrasonic waves.