JP2002337444A - Ink jet recording ink accepting layer and utilization thereof to belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording ink accepting layer, which allows a durable full color printing on a base material having at least a colored surface, and a method for ink-jet-recording by full color on the base material having the colored surface by using the ink jet recording ink accepting layer. SOLUTION: The ink jet recording ink accepting layer provided on the base material having at least the colored surface is provided under the condition that a polyurethane resin having at least one silanol group in its molecule and 10 to 70 wt.% of titanium oxide is provided. Further, in this ink jet recording method, a water-base coating agent prepared by blending titanium oxide with the water-base emulsion of the polyurethane resin having at least one silanol group in its molecule is coated onto the base material having at least the colored surface and semi-dried so as to obtain the ink accepting layer. After an ink jet recording is applied to this ink accepting layer, the polyurethane resin is cured under heat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink receiving layer for ink jet recording and its use for a belt. More specifically, the present invention particularly relates to an ink-jet recording ink-receiving layer which enables clear and durable full-color printing by ink-jet on a substrate having at least the surface thereof colored, and an ink-receiving ink for such ink-jet recording. The present invention relates to a method of performing ink jet recording on a substrate having at least the surface thereof colored using a layer, and a method of manufacturing a belt provided with a canvas having a surface subjected to full color printing by ink jet.

[0002]

2. Description of the Related Art For example, among transmission belts, a so-called coated V-belt has a canvas adhered to its periphery and bonded together to reinforce or protect an internal rubber layer.
In order to display the lot number and other information on the surface of such a canvas, conventionally, during the belt manufacturing process, for example, printing is performed by screen printing or the like.
According to this method, it is necessary to produce plates individually according to the information to be printed, which is cumbersome and expensive.

[0003] In recent years, ink jet recording has begun to be adopted, however, the canvas used for the belt is usually rubberized and has a black color, and the base is also black rubber. Therefore, in order to perform ink jet recording on the surface of such a canvas, since concealment is required, a monochromatic pigment ink such as white or yellow must be used, so-called full-color printing is difficult. is there.

In the conventional ink jet recording using a conventional pigment ink, the ink receiving layer is formed by blending a large amount of fine particles such as silica in a binder resin. The upper print easily peels off with the silica fine particles due to friction and the like, and thus the print on the canvas becomes unclear, and finally,
There is a problem of disappearance and inferior rub resistance.

Further, the binder resin in the ink receiving layer also has insufficient weather resistance and adhesiveness to canvas. For example, in the case of a power transmission belt, as described above, a large amount of fine particles are contained in the resin component. In addition, the ink receiving layer does not have sufficient flexibility to follow the running of the power transmission belt.

[0006] As described above, ink jet recording that can perform full-color and durable printing on at least the substrate whose surface is colored, including the canvas of the transmission belt, has not been hitherto known. .

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems in the conventional ink jet recording, and has been developed in such a manner that at least the surface of the substrate having a colored surface is durable. Ink-jet recording ink-receiving layer capable of performing full-color printing, and method capable of performing full-color ink-jet recording on a substrate whose surface is colored using such an ink-jet recording ink-receiving layer The purpose is to provide. Still another object of the present invention is to provide a method for producing a belt having full-color printing by ink jet recording on the surface of canvas using the ink receiving layer and the ink jet recording method.

[0008]

According to the present invention, there is provided an ink-receiving layer for ink-jet recording provided on a substrate whose surface is colored at least, and having at least one silanol group in a molecule. An ink receiving layer for inkjet recording, comprising a polyurethane resin and 10 to 70% by weight of titanium oxide is provided.

According to the present invention, there is provided an aqueous coating agent comprising an aqueous emulsion of a polyurethane resin having at least one silanol group in a molecule and titanium oxide on a substrate having at least a colored surface. An ink-jet recording method is provided in which an ink-receiving layer is coated and dried in the middle to form an ink-receiving layer, ink-jet recording is performed on the ink-receiving layer, and then heating is performed to cure the polyurethane resin.

Further, according to the present invention, there is provided a belt having a colored canvas on the surface thereof and an ink receiving layer for ink jet recording on the surface thereof, wherein the ink receiving layer has at least one silanol group in a molecule. And a belt containing 10 to 70% by weight of a titanium resin and a polyurethane resin having the following.

According to the present invention, an ink jet recording ink receiving layer containing a polyurethane resin having at least one silanol group in a molecule and 10 to 70% by weight of titanium oxide is formed on the surface of a colored canvas, After performing ink jet recording on the receiving layer, the laminate including the unvulcanized rubber sheet for the canvas and the adhesive rubber layer and the unvulcanized rubber sheet for the core wire and the compressed rubber layer is placed in a vulcanizing can. And a heating and pressurizing vulcanization method.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The ink-receiving layer for ink-jet recording according to the present invention is an ink-receiving layer for ink-jet recording provided on a substrate whose surface is colored at least, and has at least one silanol in a molecule. Group-containing polyurethane resin and titanium oxide 10 to 70% by weight
It is characterized by including.

The polyurethane resin having at least one silanol group in the molecule can be obtained as an emulsion as a commercial product. Further, a method for producing such an emulsion is described in, for example, JP-A-9-12864.

In the present invention, a substrate whose surface is at least colored is, for example, not only a case where coloring is intentionally performed for the purpose of decoration, but also a surface treatment for another purpose. As a result, the case where the surface is colored even if there is no intention of coloring is included. For example, canvas that covers some or all of the surface of the belt to protect the rubber layer of the belt or to reinforce the belt is usually rubberized and, as a result, has a black surface. According to the present invention, even in such a case, the canvas is included in the substrate whose surface is colored.

Therefore, in the present invention, the base material itself is:
It is not particularly limited, for example, paper, plastic film or sheet, rubber (elastomer) sheet,
Examples include various ceramic sheets including a glass plate, various fabrics including a canvas, plates, metal foils and plates, and various laminates thereof.

According to the present invention, titanium oxide accounts for 10 to 70% by weight of the ink receiving layer. When the proportion of titanium oxide in the ink receiving layer is less than 10% by weight, the ink receiving layer formed on such a substrate is not sufficiently opaque to the colored substrate surface, that is, the base. When full color printing is performed, the print becomes unclear. On the other hand, when the proportion of titanium oxide in the ink receiving layer exceeds 70% by weight, the ink receiving layer becomes hard, for example, when the base material is bent, the ink receiving layer is cracked, Easy to peel from. In particular, according to the present invention, the proportion of titanium oxide in the ink receiving layer is preferably in the range of 20 to 50% by weight.

In the present invention, the polyurethane resin is preferably non-yellowing. The yellowing of the polyurethane resin is said to occur when using an aromatic polyisocyanate for the polyisocyanate component,
Therefore, in the present invention, the non-yellowing polyurethane resin refers to a resin obtained by using an aliphatic polyisocyanate as the polyisocyanate.

In the present invention, the ink receiving layer may contain a resin other than the above polyurethane resin, an inorganic pigment (for example, silica), an antifoaming agent, a leveling agent, and the like, if necessary.

Such an ink-receiving layer for ink-jet recording is preferably prepared by mixing titanium oxide with an aqueous emulsion of a polyurethane resin having at least one silanol group in a molecule on a substrate whose surface is colored at least. It can be formed by applying the resulting aqueous coating agent and drying it in the middle.

The ink jet recording method according to the present invention comprises:
After performing ink jet recording on such an ink receiving layer, heating is performed to cure the polyurethane resin, and thus, durable full-color printing can be performed on such a substrate by ink jet recording. That is,
Coater, by a suitable means such as spray, apply a coating agent on the substrate, the coating layer, for example,
Even if touched by hand, it is dried to the extent that it does not adhere to the hand, and after applying ink jet printing to such an ink receiving layer, it is heated to cross-link and cure the polyurethane resin, and the water-insoluble resin And

According to such a method, the coating agent has excellent adhesion to various substrates due to its silanol groups, and the ink receiving layer formed from such a coating agent can be used for ink jet recording. Then, by heating, it crosslinks and cures itself, firmly adheres to the substrate, and reacts with the titanium oxide in the ink receiving layer and the pigment in the inkjet ink captured in the ink receiving layer, Adhere and fix to the ink receiving layer.

Thus, according to the present invention, the ink receiving layer itself is excellent not only in concealing property against the underlayer, but also in water resistance and abrasion resistance. The printed layer is also excellent in water resistance and rub resistance, and is dark and clear. That is, according to the present invention, since the ink receiving layer has a high concealing property due to titanium oxide, a dark and clear full-color printing is also performed by inkjet recording even on a substrate whose surface is colored. be able to.

In the present invention, as is apparent from the above description, an ink containing a pigment as a colorant is preferably used as the aqueous inkjet ink. An ink using both of them can be used.

The present invention can be preferably applied particularly to the production of a belt in which information is displayed in full color by ink jet recording on a canvas bonded to a rubber layer. That is, according to the present invention, an ink receiving layer is formed on the surface of a canvas, and ink jet recording is performed on the receiving layer. The laminate containing the unvulcanized rubber sheet for the compressed rubber layer is vulcanized under heating and pressure in a vulcanizer to obtain a belt.

In particular, according to the present invention, also in this case, as described above, the aqueous coating agent is applied on a canvas, and is dried in the middle to form an ink receiving layer. After that, heating is performed to cure the polyurethane resin, thus forming an ink receiving layer having excellent water resistance and rub resistance and a full-color printing layer by inkjet.

Here, the ink receiving layer according to the present invention is flexible based on the characteristics of the polyurethane resin. Thus, for example, an ink receiving layer as described above is formed on the surface of a canvas, and ink jet recording is performed on the ink receiving layer to protect or reinforce the transmission belt. The ink receiving layer does not peel off from the canvas.

However, according to the present invention,
After manufacturing a belt in which the rubber layer is reinforced or protected with canvas, information such as a lot number may be printed on the surface of the canvas by inkjet recording.

[0028]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples. In the following, the amount of the polyurethane resin emulsion used is in terms of solid content.

Example 1 A non-yellow-modified polyurethane resin emulsion having a silanol group in the molecule (Takelac XW manufactured by Takeda Pharmaceutical Co., Ltd.)
-75-X35 (solid content 30% by weight)) 90% by weight and titanium oxide (Taipaek R-780 (average particle size 0.24 μm) manufactured by Ishihara Sangyo Co., Ltd.) 10% by weight and mixed well with a mixer. Thus, an aqueous coating agent was obtained.

After the above coating agent is applied to the surface of the rubberized black canvas using a wire bar, the coating agent is left at room temperature for 2 hours, and even if it is touched with a hand, the coating layer is in a state where the coating layer does not adhere to the hand. After drying, an ink receiving layer was formed.

Using a pigment ink jet printer (MC-2000, manufactured by Seiko Epson Corporation), letters (Y, M, C and Bk) are printed on the ink receiving layer with the pigment ink jet ink, and then printed. The ink-receiving layer was dried, crosslinked and cured by heating in an oven at 20 ° C. for 20 minutes.

The printed canvas thus obtained is wound around the peripheral surface of a cylindrical forming drum having a smooth surface.
After winding the unvulcanized sheet of the rubber compound for the adhesive rubber layer of above, the polyester core wire is spirally spun on the sheet, and the rubber compound for the second adhesive rubber layer is not further formed thereon. A vulcanized sheet and a rubber compound unvulcanized sheet for a compressed rubber layer were wound to form a laminate.

[0033] The laminate pressure 6 kgf / cm ^2, the external pressure 9 kgf / cm ^2, temperature of 165 ° C., heated and pressurized at a vulcanizer in under conditions of time 35 minutes, then steam vulcanized to give a cyclic product Was. Next, the annular member is attached to a first drive system including a drive roll and a driven roll, and a plurality of ribs are formed on a surface thereof by a grinding wheel while running under a predetermined tension. The annular member is attached to a second drive system including a further driving roll and a driven roll, and is cut into a predetermined width while running, so that the product is V as a product having three ribs and a circumference of 1000 mm. A ribbed belt was obtained.

With respect to the V-ribbed belt thus obtained, the printability was evaluated and the bending resistance and the friction resistance of the printed layer were examined as follows. Table 1 shows the results.

Printability The printed layer on the belt surface was visually inspected, and a mark was given when the print was clearly discriminated, and a mark was given when the print was unclear and difficult to discern.

Bending resistance The belt was bent to visually inspect whether or not the ink receiving layer was peeled off from the canvas. When the ink receiving layer was not cracked and did not peel off from the canvas, it was evaluated as ○. Or, when the ink receiving layer was peeled off from the canvas, it was evaluated as x.

After the belt was immersed in water for 3 hours, the print on the surface of the canvas was rubbed in water, and when there was no change in the print, ○ was given, and when the print was distorted or disappeared, × was given. .

Example 2 Example 1 was repeated except that 70% by weight of the same polyurethane resin emulsion and 30% by weight of titanium oxide were used as in Example 1.
In the same manner as described above, an aqueous coating agent was prepared, applied to the surface of the canvas, and then left at room temperature for 2 hours.
After drying, an ink receiving layer was formed. After printing characters on this ink receiving layer in the same manner as in Example 1, 12
The ink-receiving layer was dried, crosslinked and cured by heating in an oven at 0 ° C. for 20 minutes.

Using the canvas thus printed, a V-ribbed belt was obtained in the same manner as in Example 1, and the printability of the surface of the canvas was evaluated in the same manner as in Example 1. The bending resistance and friction resistance of the printed layer were examined.
Table 1 shows the results.

Example 3 Example 1 was repeated except that the same 30% by weight of polyurethane resin emulsion and 70% by weight of titanium oxide were used as in Example 1.
In the same manner as described above, an aqueous coating agent was prepared, applied to the surface of the canvas, and then left at room temperature for 2 hours.
After drying, an ink receiving layer was formed. After printing characters on this ink receiving layer in the same manner as in Example 1, 12
The ink-receiving layer was dried, crosslinked and cured by heating in an oven at 0 ° C. for 20 minutes.

Using the canvas thus printed, a V-ribbed belt was obtained in the same manner as in Example 1, and the printability of the canvas surface was evaluated in the same manner as in Example 1. The bending resistance and friction resistance of the printed layer were examined.
Table 1 shows the results.

Comparative Example 1 A polyurethane resin emulsion having no silanol group in the molecule (Takelac W-10 manufactured by Takeda Pharmaceutical Co., Ltd.)
An aqueous coating agent was prepared in the same manner as in Example 1 except that 5) was used, and after applying this to the surface of the canvas,
The ink-receiving layer was left at room temperature for 2 hours and dried to the extent that the coating layer did not adhere to the hand even if touched by hand, thereby forming an ink receiving layer.

After printing was performed on this ink receiving layer in the same manner as in Example 1, the ink receiving layer was heated in an oven at 120 ° C. for 20 minutes, and the ink receiving layer was dried, crosslinked, and cured.

Using the canvas thus printed, a V-ribbed belt was obtained in the same manner as in Example 1, and the printability of the canvas surface was evaluated in the same manner as in Example 1. The bending resistance and friction resistance of the printed layer were examined.
Table 1 shows the results.

Comparative Example 2 An aqueous coating agent was prepared in the same manner as in Example 1 except that 95% by weight of the same polyurethane resin emulsion and 5% by weight of titanium oxide were used as in Example 1, and this was coated on the surface of a canvas. And then left at room temperature for 2 hours and dried halfway to the extent that the coating layer did not adhere to the hands even if touched by hand to form an ink receiving layer. After printing was performed on this ink receiving layer in the same manner as in Example 1,
Heat in an oven for 20 minutes to dry the ink receiving layer,
Cured.

Using the canvas printed in this manner, a V-ribbed belt was obtained in the same manner as in Example 1, and the printability of the canvas surface was evaluated in the same manner as in Example 1. The bending resistance and friction resistance of the printed layer were examined.
Table 1 shows the results.

Comparative Example 3 Example 1 was repeated except that the same 20% by weight of polyurethane resin emulsion and 80% by weight of titanium oxide were used as in Example 1.
In the same manner as described above, an aqueous coating agent was prepared, applied to the surface of the canvas, and then left at room temperature for 2 hours.
After drying, an ink receiving layer was formed. After printing on this ink receiving layer in the same manner as in Example 1, 120
The ink-receiving layer was dried, crosslinked and cured by heating in an oven at 20 ° C. for 20 minutes.

Using the canvas printed in this way, a V-ribbed belt was obtained in the same manner as in Example 1, and the printability of the surface of the canvas was evaluated in the same manner as in Example 1. The bending resistance and friction resistance of the printed layer were examined.
Table 1 shows the results.

[0049]

[Table 1]

[0050]

As described above, according to the present invention, there is provided an ink-jet recording ink receiving composition comprising a polyurethane resin having at least one silanol group in a molecule and titanium oxide on a substrate whose surface is colored at least. By forming a layer and performing ink jet recording thereon, it is possible to form a dark and clear full-color printing layer having excellent water resistance and abrasion resistance.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) D06P 5/00 111 B41J 3/04 101Y 101Z F term (reference) 2C056 EA11 EA13 EE08 FB01 FB03 FC06 HA46 2H086 BA01 BA15 BA22 BA33 BA36 4H057 AA01 CA23 CA38 CB08 CB39 CB47 CC01 DA01 DA34 GA06

Claims (5)

[Claims] 1. An ink-receiving layer for ink-jet recording provided on a substrate whose surface is at least colored, comprising a polyurethane resin having at least one silanol group in a molecule and 10 to 70% by weight of titanium oxide. An ink receiving layer for ink jet recording, comprising: 2. An aqueous coating agent obtained by mixing titanium oxide with an aqueous emulsion of a polyurethane resin having at least one silanol group in a molecule is applied on a substrate whose surface is colored at least. An ink-jet recording method comprising: drying the ink-receiving layer to form an ink-receiving layer; performing ink-jet recording on the ink-receiving layer; and heating and curing the polyurethane resin. 3. A belt having a colored canvas on its surface and an ink receiving layer for ink jet recording on its surface, wherein said ink receiving layer is made of a polyurethane resin having at least one silanol group in a molecule and an oxidized polyurethane resin. Titanium 10
A belt comprising about 70% by weight. 4. A polyurethane resin having at least one silanol group in the molecule and 10 to 70% by weight of titanium oxide.
After forming an ink-receiving layer for ink-jet recording containing on the surface of a colored canvas and performing ink-jet recording on this receptor layer, an unvulcanized rubber sheet, a core wire and a compressed rubber for the canvas and the adhesive rubber layer are formed. A method for producing a belt, comprising heating and pressing vulcanizing a laminate including an unvulcanized rubber sheet for a layer in a vulcanizer. 5. The method for producing a belt according to claim 4, wherein an aqueous coating agent obtained by blending titanium oxide with an aqueous emulsion of a polyurethane resin having at least one silanol group in a molecule is applied on canvas. middle,
A method for producing a belt, comprising drying to form an ink receiving layer, performing ink jet recording on the ink receiving layer, and then heating to cure the polyurethane resin.