JP2002332457A - Water-soluble ultraviolet curing adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-soluble ultraviolet curing adhesive having a function bonding piezoelectric crystal, quartz glass or ceramic to a metal, which is curable and fixable within several seconds and can release and recover cut wafer from an adhesive layer in a short time by immersing whole cut wafer bonded and fixed on a mounting stand into water after completion of cutting step which is the following step. SOLUTION: This water-soluble ultraviolet curing adhesive is obtained by carrying out radical polymerization or cationic polymerization or anionic polymerization of a component comprising a photopolymerizable prepolymer obtained by carrying out crosslinking polymerization of a photopolymerization reaction group to molecular end of a water-soluble polymer having a hydrophilic group such as hydroxy group, carboxy group or amino acid group, a photopolymerizable monomer which is a reactive diluent having low viscosity and a photoinitiator which are used as basis and further, a coloring agent, filler and a modifier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a single crystal piezoelectric material such as quartz, lithium tantalate, lithium niobate, lithium tetraborate, langasite, gallium arsenide, silicon, and the like. Water-soluble UV-curable adhesive used when bonding a crystal ingot to a cutting single crystal ingot attaching table or fixing quartz glass or ceramics (including piezoelectric ceramics) to a cutting work mounting table, especially High accuracy of 15 ″ or less in the crystal unit which is the heart of the functional components used for mobile phones in the field of mobile communications requiring high stability and high quality and as the source of various reference signals in the field of optical communications Water that can be used for high-precision bonding and fixing of a crystal ingot that can realize a crystal plate that requires a cutting angle of water and removal of the bonding layer of the crystal plate after cutting In that it provides sexual UV curable adhesive. After measuring the cleavage azimuth to determine the target angular position of the crystal ingot above the ultraviolet curing adhesive layer, the transmittance 1
By irradiating ultraviolet rays efficiently to the ultraviolet adhesive layer from the upper surface of the 00% quartz ingot, it can be cured and fixed in a short time of several seconds or less, and after the completion of the next cutting step, the cut wafer of the mounting table fixed and bonded. By immersing it in water,
The feature is that the cut wafer can be peeled and collected from the adhesive layer in a short time. In particular, when fixing a single crystal ingot (including a silicon single crystal ingot), quartz glass, and ceramics to a cutting work attaching table for a wire saw, water-soluble ultraviolet (Ult) as a component of a water-soluble ultraviolet-curing adhesive is used.
ra Violet (UV) curing adhesive, and a new type of water-soluble adhesive that can improve work efficiency and increase productivity by using an environmentally friendly water-soluble polymer material for the UV curing adhesive peeling process after cutting. It is to provide a functional ultraviolet curing adhesive.

[Prior art]

[0002] A single crystal, in particular, a Lambert-processed quartz crystal after azimuth measurement using an X-ray diffractometer using a X-ray diffractometer, is bonded to a reference plate, which is a single crystal affixing table for cutting, and a cut quartz wafer after being cut by a wire saw. The separation and recovery of the adhesive layer is an important problem. It is important to determine the target angle of the crystal ingot so that a crystal wafer that is stable over a wide temperature range and has little variation can be obtained. Other piezoelectric materials such as lithium tantalate, lithium niobate, lithium tetraoxide, langasite, and gallium arsenide are widely used as filters and vibrators in mobile communication devices and optical communication devices. On the other hand, quartz, lithium tantalate, and the like are used for wavelength plates, optical filters, and the like that are used in the field of optical signal processing such as DVDs by utilizing the birefringence and wavelength selectivity of piezoelectric materials. Also, large-diameter silicon single crystals in the semiconductor industry occupy an important position in the semiconductor field as a basic material for wafers for the semiconductor industry. By the way, the piezoelectric material used as a material constituting the piezoelectric device includes a quartz crystal or a single crystal of an ingot such as lithium tantalate, lithium niobate, lithium tetraborate, langasite, gallium arsenide at a predetermined cutting angle. It is necessary to cut with high precision. It is also necessary to precisely cut a large-diameter silicon single crystal ingot as a semiconductor material in a desired cutting direction. Generally, a thermosetting adhesive or an instant adhesive is used for fixing the ingot after measuring the azimuth of the single crystal ingot before cutting. Recently, as a method for fixing single crystals, quartz glass, and ceramics, ultra violet (UV) without applying heat is used.
Curing adhesives are used, and mainly organic solvent peeling type ultraviolet curing adhesives are used.

[0003]

According to such a conventional method of fixing a single crystal ingot after measuring an azimuth angle by heat, after heat curing, the initially determined single crystal single crystal ingot is displaced from the azimuth angle. Is generated. Also, after temporarily fixing the outer periphery of the single crystal ingot with instant adhesive, cutting
It is necessary to fix the position of the single crystal ingot during the cutting process and fix it so that the wafer after cutting does not scatter, but between the single crystal ingot and the reference plate which is the work mounting table for cutting, It is not possible to fill the reinforcing adhesive. Further, even if an ultraviolet curable adhesive is used, there are the following problems. Ultraviolet irradiation is performed on the entire surface of the single crystal ingot. in this way,
Since the ultraviolet curing reaction is fast, the curing shrinkage is large, and the stress inside the resin is also large, and the position of the ingot is deviated from the initial cutting angle position, which may cause an angle change. Usually, the filler contained in the ultraviolet curing adhesive is
Although it has the effect of alleviating the stress, a positional shift occurs due to a change in the apparatus itself due to a rise in temperature during the irradiation of ultraviolet rays, and there is a limit to the fine precision angle setting. Conventional single crystal X
The line diffraction apparatus needs a function of correcting the angle of a single crystal ingot. The establishment of a method for independently setting the angles of a plurality of single crystal ingots with high precision independently is strongly demanded from the viewpoint of mass production. Quartz glass and ceramics as wafer slicing materials are important materials as photomask materials and dielectric electronic component materials, and there is a problem in the method of curing and bonding, and the method of peeling and recovering wafers after cutting.

[0004]

Means for Solving the Problems The water-soluble ultraviolet-curable adhesive of the present invention is obtained by curing a lambard-processed artificial quartz, which is a single crystal ingot, on a work stick for cutting a wire saw at a certain time in the past. The fact that the artificial quartet, which had been hardened and bonded until yesterday, was detached from the cutting work attaching table when it was left to be attached to the wire saw the next day, and which was firmly bonded until yesterday, is the starting point of the present invention.
It is presumed that the reason why the Lambert-processed artificial quartz was detached from the work attaching table for cutting was that the ultraviolet-curing adhesive absorbed moisture in the air and the adhesive strength was reduced. In particular, in the cutting process using a wire saw, since the cutting is performed in a slurry (abrasives that are free abrasive grains are dispersed in oil), the cutting is performed during the cutting because the adhesive layer is in an oil liquid that does not allow moisture to enter. Since the cured adhesive layer cannot absorb moisture, it can keep its original cured state (by cutting immediately after UV curing), without peeling the adhesive,
An experiment was conducted on the assumption that if the wafer was immersed in water after cutting, the adhesive adhered to the cut wafer would be dissolved in water and the wafer could be peeled and collected. As a result, the wafer could be peeled and collected as expected. The greatest feature is that the adhesive stripping operation, which is the operation of collecting the wafer after cutting, can be very easily hydrolyzed only by immersion in water. The water-soluble UV-curable adhesive of the present invention comprises: A water-soluble UV-curable adhesive that has the function of bonding piezoelectric crystals, silicon single crystals, quartz glass, and ceramics to metal, with a water-soluble polymer consisting of a hydrophilic group such as a hydroxyl group, carboxyl group or amino acid group as the skeleton. A crosslinkable polymerization reaction of the photopolymerization reactive group for crosslinking at the molecular end of the photopolymerizable prepolymer is obtained by crosslinking polymerization to a state in which the water-soluble function before the transition from water solubility to swelling is maintained. Radical polymerization, cationic polymerization, or anionic polymerization, which is a photopolymerization reaction, using a photopolymerizable monomer and a photoinitiator, which are viscosity-reactive diluents, as a base solvent and a colorant, filler, and modifier added thereto. It is characterized by having made it. 2. Cellulose-based semi-synthetic polymers as water-soluble polymers, polyvinyl alcohol as starch-based or synthetic products, polyethylene glycol, polypropylene glycol, polyvinyl ether, sodium polyacrylate,
It is characterized by being a polyethylene oxide. 3. The photopolymerization reactive group is characterized by a double structure of an acrylate ester or a methacrylate ester, or a functional group of an acryloyl group or a methacryloyl group.

The water-soluble ultraviolet-curable adhesive of the present invention can be cured at room temperature in a short time by irradiating ultraviolet rays as a fundamental property of the ultraviolet-curable adhesive, and maintains the cured and intact state of the ingot as a material during the cutting operation. However, the purpose here is to completely remove the adhesive layer hardened after the completion of the cutting step in the slurry by the free abrasive grains with water without using an organic solvent. For this purpose, it is a material that combines the two properties of a water-soluble polymer and ultraviolet curing. The field of application of the water-soluble UV-curable adhesive of the present invention will be used in the most basic single crystal wafer cutting process in the electronics field. Piezoelectric single crystal materials (quartz, lithium tantalate,
For lithium niobate, lithium tetraformate, langasite, gallium arsenide, etc.) and large-diameter silicon single crystals, the cutting process is performed in a slurry in which oil and an abrasive are mixed,
In particular, since the UV-curable adhesive used is water-soluble, the wafer can be easily separated and collected simply by immersing it in water after cutting. In particular, it has also been found that the use of warm water for the work of peeling the ultraviolet-curable adhesive makes it possible to further reduce the peel time. By performing cutting with a wire saw as a cutting method, a wafer having good parallelism and a high-precision cutting angle can be obtained.

[0006] Compared with the UV-curable adhesive for fixing various ingots used in the water-soluble UV-curable adhesive of the present invention, an X-ray-curable adhesive with X-rays having an energy of several thousand times or more of ultraviolet rays is used. Use is also possible. Using X-rays from the same X-ray source as the azimuth angle measurement,
Curing time is 0.1 seconds or less. Since there is a limit to the transmission thickness of X-rays, X-ray irradiation from the side surface of the adhesive layer is effective.
The water-soluble UV-curable adhesive according to the present invention can be said to be an excellent method practically and functionally.

[0007] Among the single crystals to which the present invention is applied, quartz is required to have the most accurate cutting orientation, but the conventional quartz ingot is fixed on an X-ray diffractometer and after the cutting azimuth angle is determined. Is a two-stage temporary fixing operation, which is a temporary fixing operation that immediately performs partial ultraviolet irradiation fixing and a fine adjustment fixing operation, and then performs a final fixing operation. It has already been confirmed that this fixing work does not cause a shift in the azimuthal position of the crystal ingot even when the reference plate on which the crystal ingot is temporarily fixed is removed from the X-ray diffraction apparatus or the X-ray diffraction apparatus. . In the single-crystal X-ray diffraction system of the present invention, for silicon, gallium arsenide, and ceramics having no transparency to ultraviolet rays, quartz glass is used as a dummy pedestal by X-ray diffraction. After the azimuth is determined, the object can be similarly achieved by temporarily fixing by irradiating ultraviolet light from the side surface and irradiating ultraviolet light from the back surface.

【Example】

Next, an embodiment of the water-soluble UV-curable adhesive of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the components of a water-soluble UV-curable adhesive according to an embodiment of the present invention. FIG. 2 shows the relationship between the degree of cross-linking and the water absorption for the synthesis of a photopolymerizable prepolymer, which is a basic property of a water-soluble ultraviolet curable adhesive. FIG. 3 shows the time of immersion in water and the time of peeling of the adhesive for the water-soluble UV-curable adhesive of the present invention. FIG. 4 shows an application of the ultraviolet-curable adhesive of the present invention for fixing a Lambert artificial quartz crystal in an X-ray diffractometer.

FIG. 1 shows the components of a water-soluble UV-curable adhesive according to an embodiment of the present invention. A photopolymerizable prepolymer obtained by crosslinking and polymerizing a photopolymerization reactive group at the molecular end of a water-soluble polymer composed of a hydrophilic group may have a skeleton structure selected according to the required performance of the adhesive, but has a high viscosity, or Many of them are solid at room temperature, and their workability is poor and impractical for use as they are. (S101) The photopolymerizable monomer is used as a low-viscosity reactive diluent to improve this point. (S102) The photoinitiator absorbs ultraviolet energy by irradiating ultraviolet light to make it self-excited, thereby generating a radical for initiating a polymerization reaction of a photopolymerizable prepolymer or a photopolymerizable monomer. The properties required as a photoinitiator are that it efficiently absorbs and activates ultraviolet energy and has a high curing rate. Dissolves well in photopolymerizable prepolymers and photopolymerizable monomers. It is stable against heat, natural light, fluorescent light and the like. apparatus,
Does not corrode substrate. Does not discolor the cured resin. It is cheap. Low volatility and low toxicity. Since the photoinitiator has many solids, a stirring method for uniformly dispersing the photoinitiator is employed. A sensitizer alone is not activated by irradiation with ultraviolet light, and is more effective than a photoinitiator alone when irradiated with ultraviolet light in the presence of a photoinitiator. Types include amines, ureas, sulfur compounds, nitrile compounds, phosphorus compounds, chlorine compounds, and nitrogen compounds. (S
103) Since ultraviolet rays are light having a wavelength of 10 to 400 nm, even if the ultraviolet curing adhesive is irradiated with ultraviolet rays, the light is blocked during the irradiation and does not cure. Therefore, there is a problem of coloring (selection of pigment). In the case of an ultraviolet-curing adhesive, it is advantageous to be transparent and colorless because ultraviolet light needs to reach the interface with the adherend. However, the adhesive is colored for visual check. Ultramarine light easily transmits ultraviolet light, but titanium oxide and zinc white hardly transmit ultraviolet light, and carbon black does not transmit at all. (S104) By mixing the filler into the ultraviolet curable adhesive, it is possible to increase the amount, alleviate the curing shrinkage, improve the adhesion, and improve the moisture resistance. Fillers mainly include inorganic materials such as crystalline and fused silica, glass fiber, mica, and calcium carbonate, cellulose, and inert polymers (plasticizers).
And other organic materials. In the case of an ultraviolet-curable adhesive, the reaction is fairly rapid, so that the curing shrinkage during curing is large, and the stress inside the adhesive is large accordingly. In the case of the ultraviolet curing adhesive, when the stress acts on the bonding surface, the bonding strength is reduced. The filler has the effect of alleviating the stress internally. (S105) The modifier for the ultraviolet curable adhesive includes a thermal polymerization catalyst, a thixotropy-imparting agent, an adhesion improver, and a storage stabilizer. UV curable adhesives cure from the surface of the adhesive, making it difficult for ultraviolet light to reach deep areas when the coating thickness is large.In addition, if there is a shadow in the shape, it will be uncured or insufficiently cured. Irregularities occur, reducing the adhesive strength. Therefore, an organic peroxide (thermopolymerization catalyst) is added in advance, and the heat at the time of UV irradiation or heat treatment after UV curing is used to cure the uncured portion that has become the adhesive interface or shadow. Can be. in this case,
Since the adherend is fixed by ultraviolet curing, no displacement occurs during the heat treatment. Add a thixotropy-imparting agent to an ultraviolet-curing adhesive, and it is easy to build up like a cream,
Gives the property of not flowing out to the surroundings. The thixotropic agent includes silica-based powder, asbestos, organic fiber, and calcium carbonate-based fine powder. As the adhesion improving agent, one having a group called a coupling agent which reacts with the adhesive and a group which reacts with the adherend, and which mediates the adhesion between the two is used. Coupling agents include silicone, titanate,
There is a phosphoric acid type, and the addition amount is about 0.1 to 5.0% by weight. (S106) A water-soluble ultraviolet-curable adhesive is obtained from the components S101 to S106 of the water-soluble ultraviolet-curable adhesive of the present invention. (S107)

FIG. 2 shows the relationship between the degree of cross-linking and the water absorption of a photopolymerizable prepolymer, which is a basic property of a water-soluble UV-curable adhesive. A water-soluble polymer consisting of a hydroxyl group, carboxyl group or amino acid group is used as a skeleton to maintain the water-soluble function immediately before the cross-linking polymerization reaction of the photopolymerization reactive group for cross-linking is shifted from water-soluble to swellable at the molecular end. When a water-soluble polymer comprising a hydrophilic group, which is a photopolymerizable prepolymer cross-linked and polymerized to a state in which the polymer is cross-linked, the cross-linking density of the polymer increases as shown in FIG. 2, and the properties of the polymer change from water-soluble to swellable. Changes to a hydrophilic polymer.

FIG. 3 shows the immersion time of the water-soluble UV-curable adhesive of the present invention in water and the peeling time of the adhesive. It can be seen that the stripping time is shorter with hot water than with normal temperature water and with hot water than with hot water. As the water-soluble ultraviolet-curable adhesive used in the experiment, an acrylic polymer emulsion having a skeleton of a photopolymerizable prepolymer of 30 to 40% by weight was used. It took 80 minutes to remove 120 minutes at 25 ° C. in the shape of the adhesive layer having a thickness of 15 mm and a thickness of 3 mm.
In hot water at ℃ ° C., the adhesive could be peeled off in about one sixth in 20 minutes, and the adhesive cured in the hot water was completely dissolved and disappeared. In addition,
It was also found that the time did not change even if the ultraviolet irradiation time was changed. A practical level of peeling effect can be expected,
Post-processing is also simple.

FIG. 4 shows an example in which the water-soluble UV-curable adhesive of the present invention is applied to the application of a Lambert-processed quartz, and as shown in FIG. 4, Kα ₁ (1.5374) of copper Cu from an X-ray tube 401.
The incident X-ray 403 of Å) passes through the slit 402 and enters the incident point 4.
At 04, the light is reflected by the crystal r-plane which is a Lambertian processed crystal 420, and enters a scintillation counter 414 which is an X-ray detection unit as reflected X-ray 413. Size 60 × 80m
Lanvard processed crystal 406 of Z plate with m length 200mm
(407) is a quartz glass substrate 4 having a size of 350 × 250 mm ² to which a water-soluble ultraviolet curing adhesive 408 is applied.
05 is mounted on the reference panel 428. The reference panel 428 is set on a level frame 412 fixed at fixed ends 415 and 416 of the X-ray diffraction apparatus. The scintillation counter 414 is placed at a position of 2θ since the inter-plane distance of the crystal lattice of the atomic plane of the Lambertian-processed quartz crystal 406 (407) is known in advance by Bragg's law to be measured. When the goniometer 417 rotates the plate 420 on which the Lamberted quartz crystal 206 is placed, a diffracted beam can be obtained at 2θ where the lattice plane satisfies the diffraction condition. After detecting this peak position, in order to bond the mechanism for determining the target angle of the lumbard-processed quartz 406 and the lumbard-processed quartz 406 on the reference panel 428, an ultraviolet light source of 200 mW / cm ² with an illuminometer at 265 nm i-line. Ultraviolet light transmission guide 4 connected to 409
The ultraviolet light guided by 10 was applied to the adhesive fixing area 411 having a diameter of 20 mm from above the Lambertian-processed quartz 406 for 10 seconds to be cured. Quartz glass substrate 405
The UV-curable adhesive applied to is made based on a photopolymerizable prepolymer, a photopolymerizable monomer, and a photoinitiator (sensitizer), and is made by adding a colorant, a filler, an additive, and the like, and The basic skeleton of the photopolymerizable prepolymer includes epoxy, urethane, polyester, polybutadiene, silicone, etc., and the molecular ends of the photopolymerizable prepolymer are composed of photopolymerization reactive groups (acryloyl group, methacryloyl group, vinyl group, etc.). Here, a water-soluble acrylic ultraviolet curing adhesive was used. The water-soluble UV-curable adhesive may flow out to an unnecessary portion when the viscosity is low, and the workability is deteriorated when the viscosity is high, but the viscosity is preferably 30,000 to 40,000 cps. all right. The thickness of the water-soluble UV-curable adhesive layer is
200-500μ. After the ultraviolet irradiation, it was found that the Lamberted quartz crystal 406 was firmly fixed to the quartz glass substrate 405. The value of the Bragg angle of the lumbard-processed quartz before and after ultraviolet curing was 1 second or less. It was within the range of measurement error. Thereafter, the entire surface of the substrate was irradiated with ultraviolet rays using an ultraviolet irradiation lamp which selectively irradiates ultraviolet rays only to the lambard-processed quartz crystal 406. The change value of the Bragg angle of the lumbard-processed quartz before and after ultraviolet curing was 1 second or less. The goniometer 417 includes a servo motor 418
And a rotary encoder 419, with a minimum step having a resolution of 1 second. The measurement data processing mechanism 421 has an error signal 422 of the mechanical and electrical systems of the goniometer 417 and a rocking curve peak of the received X-ray intensity, which are caused by changes in the external environment such as temperature, humidity, and vibration, power supply fluctuation, and temperature change of the cooling water. Intensity reading error signal 423
The control signal 424 of the X-ray tube 401 for generating the correction function for K and the Kα ₁ (1.5374 °) line and the goniometer 4
Control signal 422 from the measurement data processing mechanism 421
Is controlled by a microcomputer. In the present invention, there are mechanisms 425 and 426 capable of fine adjustment movement capable of correcting a fixing error generated when the crystal ingot is fixed to the reference plate by the robot arm mechanism, and control lines 427 and 428 connected to the microcomputer. . From this, it is possible to determine the target angle of the crystal ingot for manufacturing the crystal unit requiring a high precision cutting angle error of 5 ″ or less with high precision. After all the fixing operations were completed, the next step was cut with a wire saw, and then immersed in water together with the quartz glass substrate.
In about 30 minutes, the cut quartz plate came off from the quartz glass substrate. It was also found that immersion in warmer water at a slightly higher temperature is better for further shortening the stripping time. The use of the water-soluble UV-curable adhesive as described above also has a great feature that a high-precision single crystal X-ray diffraction system excellent in mass productivity can be provided.

After measuring the azimuth of a conventional single crystal ingot,
Although a low melting point thermosetting adhesive is used to fix the position of the single crystal ingot, an azimuth shift occurs because the heating temperature of the adhesive is applied to the single crystal ingot. An ultraviolet curable adhesive has been studied as a method that does not apply a temperature, but it needs to be peeled off with an organic solvent. However, by making the UV-curable adhesive used in the single crystal X-ray diffraction system according to the present invention water-soluble, it is possible to provide an environment-friendly water-soluble UV-curable adhesive, and to finish a short time peeling and collecting operation in a short time. The ability to do so is also a great feature.

[0014]

As described above, since the water-soluble UV-curable adhesive of the present invention utilizes ultraviolet light, it can save energy, prevent environmental pollution, and save labor in the process. In particular, the UV-curable adhesive of the present invention has Water solubility is of great industrial value because the wafer recovery operation after cutting can utilize simple hydrolysis just immersed in water. In addition,
The result obtained by the present invention is not limited to quartz, and quartz has been mainly described as a piezoelectric material.However, other piezoelectric materials such as lithium tantalate, lithium niobate, lithium tetraformate, langasite, gallium arsenide, The same applies to large-diameter silicon, quartz glass and various ceramics, and needless to say.

[Brief description of the drawings]

FIG. 1 shows the components of a water-soluble UV-curable adhesive according to an embodiment of the present invention.

FIG. 2 shows the relationship between the degree of cross-linking and the water absorption of a photopolymerizable prepolymer, which is a basic property of a water-soluble UV-curable adhesive.

FIG. 3 shows the immersion time of water in the water-soluble UV-curable adhesive of the present invention and the peeling time of the adhesive.

FIG. 4 shows an application of the ultraviolet-curable adhesive of the present invention for fixing a Lambert artificial quartz crystal in an X-ray diffraction apparatus.

[Explanation of symbols]

 S101 Photopolymerizable prepolymer S102 Photopolymerizable monomer S103 Photoinitiator (sensitizer) S104 Colorant S105 Filler S106 Modifier (additive) S107 Water-soluble ultraviolet curing adhesive 401 X-ray tube 402 Slit 403 Incident X Line 404 Reflection point 405 Quartz glass substrate 406 Artificial quartz ingot 407 Artificial quartz ingot 408 Water-soluble ultraviolet curing adhesive 409 Ultraviolet light source 410 Ultraviolet waveguide guide 411 Adhesion area 412 Level frame 413 Reflected X-ray 414 Scintillation counter 415 Fixed end 416 Fixed End 417 Goniometer 418 Servo motor 419 Rotary encoder 420 Tokiwa 421 Measurement data processing mechanism 422 Mechanical / electrical error signal 423 Reading error signal 424 Reading error signal 425 Moving mechanism 42 6 Moving mechanism 427 Control line 428 Control line

Claims (3)

[Claims] 1. A water-soluble ultraviolet-curing adhesive having a bonding function between a piezoelectric crystal, a silicon crystal, quartz glass, and a ceramic and a metal, wherein a water-soluble polymer comprising a hydrophilic group such as a hydroxyl group, a carboxyl group or an amino acid group is used as a skeleton. A photopolymerizable prepolymer in which the properties of the photopolymerizable prepolymer are changed from water-soluble to swellable so as to retain the water-soluble function before cross-linking and polymerizing a photopolymerizable reactive group at the molecular end of the water-soluble polymer. A radical polymerization or cation with a component obtained by adding a photopolymerizable monomer and a photoinitiator, which are low-viscosity reactive diluents, to the photopolymerizable prepolymer as a base solvent and further adding a colorant, a filler, and a modifier thereto. Water-soluble UV-curable adhesive characterized by polymerization or anion polymerization 2. The water-soluble polymer is a semi-synthetic polymer such as cellulose, starch or a synthetic product such as polyvinyl alcohol, polyethylene glycol, polypropylene glycol, polyvinyl ether, sodium polyacrylate, and polyethylene oxide. The water-soluble UV-curable adhesive according to claim 1, characterized in that: 3. The photopolymerization reactive group includes an acrylate ester,
2. The water-soluble ultraviolet-curable adhesive according to claim 1, wherein the methacrylic acid ester has a double structure, an acryloyl group, or a functional group of a methacryloyl group.