Inkjet printing ink for ultrasound probes, method of preparation and use

Abstract

The application discloses an inkjet printing ink for an ultrasonic probe, a preparation method and application. The prepared ink is prepared from the following components and in the following weight percentage: epoxy resin 20-40 wt%, diluent 30-60 wt%, curing agent 20-30 wt%, nano powder 0-60 wt%, dispersing agent 1-2 wt%, and coupling agent 0.5-1 wt%. The prepared ink is deposited on a ceramic substrate through an inkjet printing head, and after curing, a matching layer film and a backing layer film are formed. The prepared ink has excellent stability, and after long-time standing, the ink does not settle, and when the inkjet printing is performed, the ink is smoothly sprayed from the printing head without blockage. The acoustic impedance of the matching layer film ranges from 2.7 to 42 MRayl, and the acoustic attenuation ranges from 5 to 9.3 dB / cm; the acoustic impedance of the backing layer film ranges from 3 to 45 MRayl, and the acoustic attenuation ranges from 18 to 32.8 dB / cm. Compared with the traditional preparation method of the matching layer and the backing layer, the matching layer and the backing layer film prepared by the application have high surface smoothness and high uniformity of components, and can be used for preparation of the ultrasonic probe.

Description

Technical fields:

[0001] This invention belongs to the field of ultrasonic probe fabrication technology, specifically an inkjet printing ink for ultrasonic probes, its fabrication method, and its application. Background technology:

[0002] An ultrasonic probe is an electronic device that transmits and receives sound waves. Currently, it is widely used in various fields, including medical diagnostics and imaging, underwater acoustic detection, and non-destructive testing. The matching layer and backing layer are crucial components of an ultrasonic probe, requiring specific acoustic impedance and attenuation requirements; otherwise, the sensitivity and bandwidth of the acoustic signal will be affected, thus impacting the detection results. Currently, the common methods for preparing the matching layer and backing layer are spin coating and grinding. However, due to the high viscosity of the materials used in these methods, uneven dispersion of components often occurs. Furthermore, the matching layer and backing layer films need to be prepared separately and then manually bonded to both sides of the piezoelectric wafer. During the bonding process, air bubbles can easily get trapped at the bonding points, and there may also be issues with uneven adhesive layer thickness or weak bonding, all of which affect the performance of the ultrasonic probe.

[0003] Inkjet printing, as an additive manufacturing method, has attracted attention in modern society due to its advantages such as high material utilization, short manufacturing cycle, and flexible processing. Therefore, it is widely used in industrial production. For the manufacture of thin film structures, inkjet printing has significant advantages over traditional processing methods in terms of ease of operation, efficiency, and high precision. Currently, the quality of inkjet printing ink determines the printing effect. Existing technologies do not have inkjet printing inks that meet the requirements for materials used in ultrasonic probes. Therefore, this application proposes an inkjet printing ink with excellent inkjet printing performance that can be applied to the matching layer and backing layer of ultrasonic probes. This ink not only has high stability and high dispersibility, but also does not settle within a short time after preparation and does not clog the nozzles during printing. Furthermore, the thin film produced meets the requirements for use in ultrasonic probes. Summary of the Invention:

[0004] The purpose of this invention is to provide an inkjet printing ink for ultrasonic probes, a preparation method thereof, and an application thereof. The inkjet printing ink for ultrasonic probes includes a matching layer ink and a backing layer ink. By printing the matching layer ink and the backing layer ink onto a piezoelectric wafer, the matching layer film and the backing layer film can be directly manufactured on the piezoelectric wafer.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] In a first aspect, the present invention provides an inkjet printing ink for an ultrasonic probe, comprising a matching layer ink and a backing layer ink.

[0007] The mass composition of the matching layer ink is as follows:

[0008] Epoxy resin: 20-30 wt%;

[0009] Diluent: 30-60 wt%;

[0010] Curing agent: 20-30wt%;

[0011] Matching layer nanopowder: 0-50 wt%;

[0012] Dispersant: 1-2 wt%;

[0013] Coupling agent: 0.5-1 wt%;

[0014] The mass composition of the backing layer ink is as follows:

[0015] Epoxy resin: 20-30 wt%;

[0016] Diluent: 30-60 wt%;

[0017] Curing agent: 20-30wt%;

[0018] Backing layer nanopowder: 10-60 wt%;

[0019] Dispersant: 1-2 wt%;

[0020] Coupling agent: 0.5-1 wt%;

[0021] The particle size of the matching layer nanopowder and the backing layer nanopowder is 30-200 nm. The matching layer nanopowder is one or more of alumina powder, titanium dioxide powder, silicon dioxide powder, zirconium oxide powder, cerium oxide powder, magnesium powder, and silver powder. The backing layer nanopowder is one or more of tungsten powder, tungsten oxide powder, lead powder, lead oxide powder, iron powder, glass, and hollow plastic microspheres.

[0022] The epoxy resin is one or more of the following: glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, linear aliphatic epoxy resin, and alicyclic epoxy resin.

[0023] The diluent is one or more of the following: an active diluent (alkylene glycidyl ether, butyl glycidyl ether, 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, phenyl glycidyl ether) or a non-active diluent (acetone, N,N-dimethylformamide, ethyl lactate, cyclopentanone, γ-butyrolactone).

[0024] The curing agent is a latent curing agent, which is one or more of the following: modified aliphatic amines, aromatic diamines, dicyandiamides, imidazoles, and organic acid anhydrides.

[0025] The dispersant is one or more of the following: polyvinylpyrrolidone, BYK-2151, BYK-2070, BYK-2050, and BYK-167;

[0026] The coupling agent is one or more of silane coupling agents, titanate coupling agents, and aluminate coupling agents.

[0027] Secondly, the present invention provides a method for preparing the inkjet printing ink for ultrasonic probes, comprising the following steps: 1) mixing epoxy resin, diluent, curing agent, dispersant and coupling agent, and magnetically stirring for 10-20 minutes to obtain a uniformly mixed solution;

[0028] 2) Add nanoparticles in batches and continuously in small amounts to the solution that was mixed evenly in step 1). After the filler is added, continue stirring for 20-30 minutes to obtain a uniformly mixed nanoparticle dispersion.

[0029] 3) The nanoparticle dispersion obtained in step 2) is subjected to ultrasonic dispersion for 30 minutes, and then the ultrasonically dispersed nanoparticle dispersion is filtered through a filter with a mesh size of 300 or higher. If the nanomaterial is a matching layer nanomaterial, a matching layer ink that meets the requirements of inkjet printing is obtained; if the nanomaterial is a backing layer nanomaterial, a backing layer ink that meets the requirements of inkjet printing is obtained.

[0030] Thirdly, the present invention provides an application of inkjet printing ink for an ultrasonic probe, wherein the matching layer ink is used for inkjet printing of a matching layer film for an ultrasonic probe, and the backing layer ink is used for inkjet printing of a backing layer film for an ultrasonic probe. The matching layer film obtained after inkjet printing has an acoustic impedance range of 2.7–42 MRayl, preferably 3–10 MRayl; and an acoustic attenuation range of 5–9.3 dB / cm, preferably 6–8 dB / cm. The backing layer film obtained after inkjet printing has an acoustic impedance range of 3–45 MRayl, preferably 4–12 MRayl; and an acoustic attenuation range of 18–32.8 dB / cm, preferably 20–30 dB / cm.

[0031] Using inkjet printing ink in the fabrication of an ultrasonic probe backing layer or matching layer includes the following steps:

[0032] 1) The matching layer ink or backing layer ink as described in claim 1 is directly printed on the piezoelectric ceramic substrate;

[0033] 2) After the ink printing is completed, cure it according to the curing process of 80℃ / 2h+120℃ / 2h+150℃ / 2h.

[0034] In step 1), the driving voltage waveform of the print head is set to trapezoidal, with a voltage amplitude of 88-92V, a duration of 5-6μs, and rise and fall times of 1.5-2.5μs.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1. The inkjet printing formulations for the matching layer and backing layer inks involved in this invention use epoxy resin and diluent as the matrix, matching layer and backing layer nanopowders as fillers, and dispersants and coupling agents as additives. The matching layer uses matching layer ink, and the backing layer uses backing layer ink. Both formulation structures meet the corresponding acoustic performance requirements, such as acoustic impedance and sound attenuation. Furthermore, the inkjet printing method can obtain corresponding films with smooth surfaces, uniform composition, and no obvious defects (such as pores). The ink formulations are simple and low-cost.

[0037] 2. The inkjet printing ink of this invention has good stability and dispersibility. According to laser particle size analyzer testing, the particle size distribution of the ink is narrow, and there is no sedimentation after one month of storage. The ink viscosity is 5-20 mPa.s, and the surface tension is 28-45 mN / m. During the printing process, the ink droplets are ejected smoothly and the printhead is not clogged. It is suitable for a variety of inkjet printing printheads.

[0038] 3. This invention directly prints and cures the matching layer ink and backing layer ink onto the piezoelectric ceramic substrate using inkjet printing, eliminating the need for an adhesive layer. The printed matching layer film has an acoustic impedance range of 2.7–42 MRayl and an acoustic attenuation range of 5–9.3 dB / cm; the printed backing layer film has an acoustic impedance range of 3–45 MRayl and an acoustic attenuation range of 18–32.8 dB / cm. Furthermore, the prepared matching layer and backing layer films have smooth surfaces, uniform composition, and no obvious defects. Compared to traditional methods for preparing matching and backing layers, inkjet printing avoids the possibility of air bubbles, uneven adhesive layer thickness, or weak adhesion during bonding, which can occur due to the presence of an adhesive layer. This simplifies the ultrasonic transducer manufacturing process and increases reliability. Attached image description:

[0039] Figure 1 This is a particle size distribution diagram of the ink particles after the matching layer ink in Example 1 has been prepared.

[0040] Figure 2 This is a morphological diagram of the matching layer ink during the jetting process in Example 1.

[0041] Figure 3 This is a scanning electron microscope image of the matching layer ink printed on the thin film surface of the PZT substrate in Example 1. Detailed implementation method:

[0042] Specific embodiments of the present invention are given below, but the implementation of the present invention is not limited thereto. Parameters not specifically specified can be performed using conventional parameters.

[0043] In the following embodiments, a material jet deposition and analysis system was used to print ink. The prepared ink was tested for viscosity using a rheometer, surface tension using a surface tension meter, and particle size analysis using a laser particle size analyzer. The ink was inkjet-printed onto a substrate, cured, and the acoustic impedance and acoustic attenuation of the matching layer and backing layer films were tested using an insertion substitution method. The microstructure of the films was then imaged using a scanning electron microscope.

[0044] Example 1

[0045] The matching layer ink for the ultrasonic probe inkjet printing has the following components: 25wt% epoxy resin EPON862, 40wt% N,N-dimethylformamide, 25wt% methylhexahydrophthalic anhydride, 8wt% 100nm spherical alumina particles, 1.5wt% polyvinylpyrrolidone, and 0.5wt% γ-aminopropyltriethoxysilane.

[0046] 1) Mix epoxy resin, N,N-dimethylformamide, methylhexahydrophthalic anhydride, polyvinylpyrrolidone, and γ-aminopropyltriethoxysilane according to the above proportions, and stir magnetically for 10-20 minutes to obtain a uniformly mixed solution.

[0047] 2) Add 100nm spherical alumina particles in batches to the well-mixed solution from step 1) while stirring at the same speed of 10r / s: Specifically, divide the required alumina particles into 5 equal portions and add them to the well-mixed solution from step 1) in batches, with an interval of 2 minutes between each batch. After all the alumina particles have been added, continue stirring for 20-30 minutes to obtain a well-mixed alumina particle dispersion.

[0048] 3) The alumina particle dispersion obtained in step 2) is ultrasonically dispersed for 30 minutes, and then the ultrasonically dispersed dispersion is filtered through a filter with a mesh size of 300 or higher to obtain matching layer ink that meets the printing requirements.

[0049] The prepared matching layer ink was tested and found to have a viscosity of 7 mPa·s and a surface tension of 40 mN / m. After being left at room temperature for one month, the ink showed no sedimentation. Laser particle size analysis revealed a median particle size of 103 nm, confirming that the ink particles did not agglomerate. The ink was tested and found to be suitable for inkjet printing.

[0050] Preparation of matching layer thin film:

[0051] 1) Set the printhead drive voltage waveform to trapezoidal, with a voltage amplitude of 90V, a duration of 6μs, and rise and fall times of 2μs each. After setting the printhead drive voltage, inkjet print the matching layer ink onto the piezoelectric ceramic substrate.

[0052] 2) After ink printing is completed, the ink is cured according to the curing process of 80℃ / 2h+120℃ / 2h+150℃ / 2h to obtain the matching layer film.

[0053] The prepared matching layer film had an acoustic impedance of 2.87 MNayl and an acoustic attenuation of 6.53 dB / cm. The prepared matching layer film had a smooth surface, uniform composition, and no obvious defects.

[0054] The matching layer ink obtained in this embodiment has uniformly dispersed particles with little or no agglomeration. Particle size testing of the ink revealed a narrow particle size distribution. Figure 1 As shown, it exhibits high dispersibility; the ink shows no sedimentation or stratification during long-term storage, demonstrating high stability; after standing at room temperature for one month, no sedimentation or stratification occurs; the prepared ink is smoothly ejected from the printhead without clogging, and the ejected ink droplets have a good shape, such as... Figure 2 As shown; from Figure 3 It can be observed that the alumina particles are uniformly dispersed in the cured film.

[0055] Example 2

[0056] The matching layer ink for the ultrasonic probe inkjet printing has the following components: 25wt% epoxy resin EPON862, 28wt% ethyl lactate, 25wt% methyl hexahydrophthalic anhydride, 20wt% 100nm spherical silica particles, 1.5wt% polyvinylpyrrolidone, and 0.5wt% γ-aminopropyltriethoxysilane.

[0057] 1) Mix epoxy resin, ethyl lactate, methyl hexahydrophthalic anhydride, polyvinylpyrrolidone, and γ-aminopropyltriethoxysilane according to the above proportions, and stir magnetically for 10-20 minutes to obtain a uniformly mixed solution.

[0058] 2) Add 100nm spherical silica particles in batches to the well-mixed solution from step 1) while stirring at the same speed of 10r / s: Specifically, divide the required silica particles into 5 equal portions and add them to the well-mixed solution from step 1) in batches, with an interval of 2 minutes between each batch. After all the silica particles have been added, continue stirring for 20-30 minutes to obtain a well-mixed silica particle dispersion.

[0059] 3) The silica particle dispersion obtained in step 2) is ultrasonically dispersed for 30 minutes, and then the ultrasonically dispersed dispersion is filtered through a filter with a mesh size of 300 or higher to obtain matching layer ink that meets the printing requirements.

[0060] The prepared matching layer ink was tested and found to have a viscosity of 18 mPa·s and a surface tension of 35 mN / m. After being left at room temperature for one month, the ink showed no sedimentation. Laser particle size analysis revealed a median particle size of 105 nm, confirming that the ink particles did not agglomerate. The ink was tested and found to be suitable for inkjet printing.

[0061] The matching layer film was prepared according to the process in Example 1. The test results showed that the acoustic impedance of the prepared matching layer film was 3.3 MNayl, the acoustic attenuation was 7.55 dB / cm, and the surface of the prepared matching layer film was smooth, the composition was uniform, and there were no obvious defects.

[0062] Example 3

[0063] The ink for the backing layer of the ultrasonic probe inkjet printing has the following components: 20wt% epoxy resin EPON862, 28wt% butyl glycidyl ether, 40wt% methyl hexahydrophthalic anhydride, 10wt% 100nm spherical tungsten particles, 1.5wt% BYK-2051, and 0.5wt% γ-aminopropyltriethoxysilane.

[0064] 1) Mix epoxy resin, butyl glycidyl ether, methyl hexahydrophthalic anhydride, BYK-2051, and γ-aminopropyltriethoxysilane according to the above proportions, and stir magnetically for 10-20 minutes to obtain a uniformly mixed solution.

[0065] 2) Add 100nm tungsten particles in batches to the well-mixed solution from step 1) while stirring at the same speed of 10r / s: Specifically, divide the required amount of tungsten particles into 5 equal portions and add them to the well-mixed solution from step 1) in batches, with an interval of 2 minutes between each batch. After all the tungsten particles have been added, continue stirring for 20-30 minutes to obtain a well-mixed tungsten particle dispersion.

[0066] 3) The tungsten particle dispersion obtained in step 2) is ultrasonically dispersed for 30 minutes, and then the ultrasonically dispersed dispersion is filtered through a filter screen of 300 mesh or higher to obtain a backing ink that meets the printing requirements.

[0067] The prepared backing ink was tested and found to have a viscosity of 20 mPa·s and a surface tension of 42 mN / m. After being left at room temperature for one month, the ink showed no sedimentation. Laser particle size analysis revealed a median particle size of 110 nm, confirming that the ink particles did not agglomerate. The ink was tested and found to be suitable for inkjet printing.

[0068] Preparation of the backing film:

[0069] 1) Set the printhead drive voltage waveform to trapezoidal, with a voltage amplitude of 90V, a duration of 6μs, and rise and fall times of 2μs each. After setting the printhead drive voltage, inkjet print the backing layer ink onto the piezoelectric ceramic substrate.

[0070] 2) After ink printing is completed, the ink is cured according to the curing process of 80℃ / 2h+120℃ / 2h+150℃ / 2h to obtain the backing film.

[0071] The prepared backing film was tested and found to have an acoustic impedance of 3 MRayl and an acoustic attenuation of 18 dB / cm. Furthermore, the prepared backing film had a smooth surface, uniform composition, and no obvious defects.

[0072] Example 4

[0073] The ink for the backing layer of the ultrasonic probe inkjet printing has the following components: 18wt% epoxy resin EPON862, 22wt% N,N-dimethylformamide, 18wt% methyltetrahydrophthalic anhydride, 40wt% 100nm spherical lead particles, 1.5wt% BYK-2050, and 0.5wt% γ-aminopropyltriethoxysilane.

[0074] 1) Mix epoxy resin, N,N-dimethylformamide, methyltetrahydrophthalic anhydride, BYK-2050, and γ-aminopropyltriethoxysilane according to the above proportions, and stir magnetically for 10-20 minutes to obtain a uniformly mixed solution.

[0075] 2) Add 100nm lead particles in batches to the well-mixed solution from step 1) while stirring at the same speed of 10r / s: Specifically, divide the required lead particles into 5 equal parts and add them to the well-mixed solution from step 1) in batches, with an interval of 2 minutes between each batch. After the lead particles are added, continue stirring for 20-30 minutes to obtain a well-mixed lead particle dispersion.

[0076] 3) The lead particle dispersion obtained in step 2) is ultrasonically dispersed for 30 minutes, and then the ultrasonically dispersed dispersion is filtered through a filter with a mesh size of 300 or higher to obtain a backing ink that meets the printing requirements.

[0077] The prepared backing ink was tested and found to have a viscosity of 12 mPa. . The ink has a surface tension of 42 mN / m. After being left at room temperature for one month, the ink showed no sedimentation. Laser particle size analysis revealed that the particle size was 105 nm, proving that the ink particles did not agglomerate. Tests have shown that this ink is suitable for inkjet printing.

[0078] The backing film was prepared according to the process in Example 3. Testing showed that the prepared backing film had an acoustic impedance of 4.6 MNayl and an acoustic attenuation of 30 dB / cm. Furthermore, the prepared backing film had a smooth surface, uniform composition, and no obvious defects.

[0079] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. An inkjet printing ink for ultrasonic probes, characterized in that, Including matching layer ink and backing layer ink, The mass composition of the matching layer ink is as follows: Epoxy resin: 20-30 wt% Diluent: 30-60 wt% Hardener: 20-30 wt% Matching layer nanopowder: 8-50 wt% Dispersant: 1-2 wt%; Coupling agent: 0.5-1wt%; The mass composition of the backing layer ink is as follows: Epoxy resin: 20-30 wt% Diluent: 30-60 wt% Hardener: 20-30 wt% Backing layer nanopowder: 10-60 wt% Dispersant: 1-2 wt%; Coupling agent: 0.5-1wt%; The sum of the mass percentages of all components in the backing layer ink and the matching layer ink is 100%. The particle size of the matching layer nanopowder and the backing layer nanopowder is 30-200 nm. The matching layer nanopowder is one or more of alumina powder, titanium dioxide powder, silicon dioxide powder, zirconium oxide powder, cerium oxide powder, magnesium powder, and silver powder. The backing layer nanopowder is one or more of tungsten powder, tungsten oxide powder, lead powder, lead oxide powder, iron powder, glass, and hollow plastic microspheres. The epoxy resin is one or more of the following: glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, linear aliphatic epoxy resin, and alicyclic epoxy resin. The diluent is one or more of an active diluent or a non-active diluent; the active diluent is one or more of alkylene glycidyl ether, butyl glycidyl ether, 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, or phenyl glycidyl ether; the non-active diluent is one or more of acetone, N,N-dimethylformamide, ethyl lactate, cyclopentanone, or γ-butyrolactone. The curing agent is a latent curing agent, which is one or more of dicyandiamide, imidazole, and organic acid anhydrides. The dispersant is one or more of polyvinylpyrrolidone, BYK-2151, and BYK-2050; The coupling agent is one or more of silane coupling agents, titanate coupling agents, and aluminate coupling agents; Laser particle size analyzer testing showed that the particle size distribution of the inkjet printing ink was narrow, and the ink did not settle after being stored for one month. The ink viscosity is 5-20 mPa·s, and the surface tension is 28-45 mN / m. During the printing process, the ink droplets are ejected smoothly and the printhead is not clogged. Moreover, inkjet printing can produce corresponding films with smooth surfaces, uniform composition, and no obvious defects.

2. A method for preparing inkjet printing ink for an ultrasonic probe as described in claim 1, characterized in that, Includes the following steps: 1) Mix epoxy resin, diluent, curing agent, dispersant and coupling agent, and stir magnetically for 10-20 minutes to obtain a uniformly mixed solution; 2) Add nanoparticles in batches and continuously in small amounts to the solution that was mixed evenly in step 1). After the nanoparticles are added, continue stirring for 20-30 minutes to obtain a uniformly mixed nanoparticle dispersion. 3) The nanoparticle dispersion obtained in step 2) is subjected to ultrasonic dispersion for 30 minutes, and then the ultrasonically dispersed nanoparticle dispersion is filtered through a filter with a mesh size of 300 or higher. If the nanoparticle powder is a matching layer nanoparticle powder, a matching layer ink that meets the requirements of inkjet printing is obtained; if the nanoparticle powder is a backing layer nanoparticle powder, a backing layer ink that meets the requirements of inkjet printing is obtained.

3. The application of the inkjet printing ink for an ultrasonic probe as described in claim 1, characterized in that, The matching layer ink is used for inkjet printing of the matching layer film of the ultrasonic probe, and the backing layer ink is used for inkjet printing of the backing layer film of the ultrasonic probe. The acoustic impedance of the matching layer film obtained after inkjet printing is in the range of 2.7-42 MRayl, and the acoustic attenuation is in the range of 5-9.3 dB / cm. The acoustic impedance of the printed backing layer film is in the range of 3-45 MRayl, and the acoustic attenuation is in the range of 18-32.8 dB / cm.

4. The application according to claim 3, characterized in that: Using inkjet printing ink in the preparation of matching layers or backing layers for ultrasonic probes includes the following steps: 1) The matching layer ink or backing layer ink described in claim 1 is directly printed onto the piezoelectric ceramic substrate; 2) After the ink printing is completed, cure it according to the curing process of 80℃ / 2h+120℃ / 2h+150℃ / 2h.

5. The application according to claim 4, characterized in that: In step 1), the driving voltage waveform of the print head is set to trapezoidal, with a voltage amplitude of 88-92V, a duration of 5-6μs, and rise and fall times of 1.5-2.5μs.

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